Laboratory Usage and Safety Manual

for the Tel-Aviv University Micro-Technology Laboratory

(TAU-Microlab)

May 2001, 2nd edition

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Table of Contents Page i) Legal Notices 5 ii) TAU-MICROLAB Safety Policy 5 1.0 Scope 6 2.0 OSHA Lab Standard 6 3.0 General Procedures 7 3.1 Categories of People 7 3.2 Access 7 3.3 New User Orientation 7 3.4 Keys 8 3.5 Places to Go and Not to Go. 8 3.6 Clean Room Etiquette 9 3.7 Clean Room Sign-in 10 3.8 Hours of Operation 10 3.9 Computer Abuse 10 3.10 User Communication 10 3.11 Facility Governance and Appeals 10 3.12 TAU-MICROLAB Safety Improvement Team 10 4.0 Equipment Use and Availability 11 4.1 Approved Users 11 4.2 Equipment Log Sheets 11 4.3 Equipment Use Charges 11 4.4 Scheduling 11 4.5 Problems 11 5.0 Laboratory Practices 13 5.1 Visitors 13 5.2 Student Storage 13 5.3 Phones and Intercom 13 5.4 Buddy System 13 6.0 Clean Room Functions 14 6.1 Contamination Control 14 6.2 Safety Glasses 14 6.3 Clean Room Apparel 14 6.4 Clean Room Facilities 14 6.5 Other House Services 15 6.6 Facilities Malfunctions and Alarms 15 7.0 Personal Chemical Safety 16 7.1 The Bottom Line on Safety 16 7.2 Safety Philosophy 16 7.3 Laboratory Hazards 18 7.4 Sources of Chemical Information 18 7.5 Terminology 21 7.5.1 Chemical Properties Terms 21 7.5.2 Types of Exposure 22 7.5.3 Types of effects 22 7.5.4 Exposure Levels 23

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7.5.5 Toxic Effects 23 7.6 Chemical Use 24 7.6.1 Chemical Authorization 24 7.6.2 Chemical Practice 24 7.6.3 Labware 24 7.6.4 Chemical Bench Operation 24 7.6.5 Hot Plates 25 7.6.6 Chemical Bench Use Rules 25 7.6.7 Chemical Storage 25 7.6.8 Chemical Supplies 28 7.6.9 Approved Mixtures 28 7.6.10 Pregnancy 28 7.6.11 Buddy System 28 7.6.12 Contact Lenses 29 7.6.13 Protective Gear for Chemical Use 29 7.6.14 Emergency Response Equipment 30 7.6.15 Chemical Accidents 30 7.6.16 Chemical Deliveries 30 7.6.17 Respirator Use Policy 30 7.6.18 Reminders and Final Checklist 32 7.7 Specific Chemical Hazards 33 7.7.1 Acetone and Flammable Solvents 33 7.7.2 Hydrofluoric Acid 33 7.7.3 Piranha and Nanostrip 34 7.7.4 Chlorinated solvents 34 7.7.5 Glycol Ethers 34 7.7.6 Peroxides 35 7.8 Chemical Waste 36 7.8.1 Disposal 36 7.8.2 Waste Handling 36 8.0 Gas Safety 36 8.1 Hazardous Gases Used 37 8.1.1 Silane 37 8.1.2 Anhydrous Ammonia 37 8.1.3 Liquid Nitrogen 37 8.2 Toxic Gas Handling and Usage 37 8.3 Toxic Gas Detection System 38 8.4 Toxic Gas Alarms 38 9.0 Emergency Services 39 Appendix 1. References 40 Appendix 2. TAU-MICROLAB Staff--Special Responsibilities 41 Appendix 3. Short and Simple Rules 42

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i) Legal Notices Laboratory Usage and Safety Manual for TAU-MICROLAB 2nd Edition, May 2001 (c) Tel-Aviv University, 2001 Document may be electronically viewed or downloaded for personal use without modification only. This document is available electronically for reference by TAU-MICROLAB Users via Web at www.eng.tau.ac.il/~microlab This manual is thought to be complete at the time of its writing and to accurately present the operational policies of TAU-MICROLAB and the dangers involved in using TAU-MICROLAB facilities. Comments regarding the contents of this manual should be directed to Prof. Yosi Shacham yosish@eng.tau.ac.il ii) TAU-MICROLAB Safety Policy The Staff and Management of the TAU-MICROLAB have implemented all reasonable measures to ensure that the laboratory provides a clean and safe working environment.

It is the responsibility of all users and staff to act in a professional, courteous, and safe manner at all times while in the facility. Users violating the operating and safety rules of the facility or endangering the safety of themselves or other users, will be denied further access to the laboratory.

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1.0 Scope This document is a reference manual covering the basic operational policies for use of the facilities in Tel-Aviv University. It applies equally to both resident and non-resident users, and governs both safety and laboratory use rules. All users are expected to have read and understood these procedures. The laboratory is a multi-user facility with an access around the clock. The facility houses an expensive and fragile equipment; it also houses chemicals which pose significant hazards if handled incorrectly. This manuscript attempts to document acceptable operating behavior for use of the TAU-MICROLAB. It is impossible, however, to define a policy for every conceivable situation. Rules and policies are no substitute for common sense. Under these conditions, anyone who fails to act in a professional, safe and responsible manner while in the TAU-MICROLAB will be banned from further use of the facility. Users' suggestions and feedback on the facility, its staff, its operation, and its equipment are welcome at all times. Please feel free to direct your suggestions to whomever you feel most comfortable with, from an individual staff member to a faculty member of the Executive Committee. 2.0 OSHA Lab Standard This laboratory follows generally the rules of the OHSA Lab Standard, 29CFR1910.1450. The Lab Standard establishes the rights of laboratory workers and mandates training programs, monitoring and other actions by the laboratory. TAU-MICROLAB applies the training requirements of the Lab Standard to all laboratory users, even non-employees. Compliance with the provisions is documented in the TAU-MICROLAB Chemical Hygiene Plan. The lab is going to be significantly upgraded to tighter monitors, please follow the instruction given by the lab manager. Mark Oksman, Lab Manager, is the designated Chemical Hygiene Officer, responsible for implementation and compliance with the OSHA Lab Standard. Questions regarding your rights under the OSHA Lab Standard should be directed to the Chemical Hygiene Officer. Other requirements of the Lab Standard are Training for all laboratory workers in Hazard identification and safe operating practices. Standard Operating Procedures Medical Examinations or consultations for laboratory workers under certain conditions Training and availability of Personal Protective Equipment Application of appropriate Engineering Controls to limit employee exposure Special precautions/procedures for particularly hazardous materials Exposure Monitoring when appropriate Record keeping The Laboratory Standard supersedes most OSHA workplace requirements for laboratory workers.

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3.0 General Procedures 3.1 Categories of People Staff Full or part time employees of TAU-MICROLAB. Users People working on an approved research project at TAU-MICROLAB (students, faculty, postdocs, engineers, etc. both from TAU or not from TAU). Users are divided into two categories. Resident Users Those people who are resident at TAU for extended periods of time, e.g. > 3 months. Non-resident users Those people who use the facility for short duration, typically 1-2 weeks, on an infrequent basis (generally from outside the TAU community). Visitors People visiting the laboratory for a brief time and having no affiliation with a User research project. Service Personnel People in the facility to service equipment and facilities. This includes both Tel-Aviv and non-Tel-Aviv employees. 3.2 Access The facility is for the exclusive use of TAU-MICROLAB staff and Users affiliated with and working on specifically approved research projects. Other use requires approval of the Director of the facility. The criteria for approval of projects is documented in the TAU-MICROLAB User Manual. Being a graduate student at Tel-Aviv does not guarantee access to the facility. Use of the facility by any individual is a privilege which can be revoked by the facility management at any time. 3.3 New User Orientation On orientation process is required before any new user can receive a key to work in the facility. Users must obtain a new key application from the TAU-MICROLAB receptionist. In the case of Tel-Aviv Users, this must be signed by a faculty member. Upon completion of the key application, the orientations sessions may be scheduled. In general this is a three part process. Part 1. Orientation A small group (< 4) prospective users are taken through the laboratory by a staff member, discussing general rules, safety procedures, emergency exits, etc. After this session, a user can be issued a key allowing basic access to the laboratory. Few people stop here, however. Parts 2 and 3 are required in order to use any chemicals in the laboratory. Part 2. Chemical Safety Lecture This 2 hour lecture/video by a Staff member covers basics of The Laboratory Standard,

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chemistry, chemical safety, and toxicology. This is done with a small group. Part 3 Chemical Lab Practical Tour This is the final section for full chemical authorization. It is done only 1 on 1 with a staff member. Emphasis is on proper technique in using chemicals and chemical safety protective equipment. To participate in orientation, users must Have completely read and understood this Lab Safety Manual Have a completed key application or Memorandum of Understanding on file Have their own safety glasses (available from TAU-MICROLAB) Be appropriately attired for clean room access In all three sessions, the staff member is looking for evidence that the user understands the language, rules, procedures, and consequences of working in the facility. The staff must evaluate whether the user can and will work safely in the laboratory. Actual approval for a key is conditioned upon their recommendation in these areas. The laboratory management may deny a key, or restrict access to particular conditions, based upon this evaluation. 3.4 Keys The clean room has an electronic access system. You will be issued a personal electronic key. You are required to use this key both to enter and to exit the facility. Failure to log out electronically will result in an alarm. Keys are issued for the sole use of one person on a specific approved user project. Permitting unauthorized access to the facility is not allowed. Non-resident users are usually issued a key only for the week in which they are using the facility. The key is your authorization to enter the facility. Persons without keys specifically issued to them are not allowed in the facility, except for brief tours accompanied by an authorized user. Your key is essentially your documentation that you have received the required orientation and safety training. Non-authorized persons are thus prohibited from accompanying, observing, and helping users at work, unless specifically approved by the laboratory management. Non-authorized persons are thus also prohibited from the role of laboratory "buddy". When you are working we want you concentrating on yourself and not on someone else. Please see section 5.4 regarding the buddy system. Loaning your keys to others is a serious violation. 3.5 Places to Go and Not to Go. TAU-MICROLAB resources are housed in the Wolfson building for Electrical Engineering. So far all the areas are accessible to the users.

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3.6 Clean Room Etiquette The laboratory is a clean room. Users must be properly attired, with hat, shoe covers, and buttoned coat. Pencils, food, and all unnecessary items are not to be taken into the clean room. Shoes should be properly clean before using shoe covers. Please read additional information in Chapter 6 on clean room functions. 3.7 Clean Room Sign-in Escorted visitors must sign in the guest book at the entrance to the clean room. The escort must sign his initials along with the guest's entry. 3.8 Hours of Operation The laboratory is open to qualified users both day and night, weekdays and weekends. Certain instruments and procedures may, however, be restricted to the normal work day, or only allowed in the presence of a staff member. (See section 5.4 and section 7.6.11 regarding the buddy system). In general, a "buddy" is another knowledgeable user within the facility who can and will watch out for you in case of trouble. Laboratory "buddies" must of necessity communicate with each other to be effective. The use of chemicals in particular is restricted to the buddy system after normal hours. You may not wet etch, mix chemicals, or dispose of waste without another user in the area. (see section 7.6.11.) Certain instruments have formal procedures for sign in by the designated "buddy", as well as rules regarding the proximity of the "buddy". These procedures will be enforced. Other procedures are totally forbidden off-hours, with or without a "buddy". Please consult with the appropriate system manager for details. 3.9 Computer Abuse Computer abuse is a violation of university policy, and may subject the abuser to various disciplinary actions from TAU-MICROLAB management, the campus judicial system, and legal authorities. Abuses of the computers at TAU-MICROLAB will have the same results as violations of TAU-MICROLAB safety rules- ranging from denial of access to the computers for a period of time to permanent exclusion from the facility. Note that this policy covers ALL computers at the TAU-MICROLAB. Computer abuse includes, but is not limited to : Using TAU-MICROLAB computer systems or networks without proper authorization, or for unauthorized purposes, including using or attempting to use an account not issued to you; Tampering with or obstructing the operation of the TAU-MICROLAB computer systems or networks, or attempting to do so; Inspecting, modifying, distributing, or copying software or other data (whether this is system software, data, or files of another user) without authorization, or attempting to do so; Supplying false or misleading information or identification in order to access TAU-MICROLAB computer systems, or attempting to do so.

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3.10 User Communication All local users must supply TAU-MICROLAB with a functional computer address, which they check daily for messages. E-mail will be the primary mechanism for staff notification of users of equipment and laboratory status information. The facility will also periodically publish a Local Users Newsletter. All local users must have a functional campus mail address. 3.11 Facility Governance and Appeals The management of the facility is responsible for the continued operation and existence of the facility. Use of the facility by any User is at the sole discretion of the management. The staff are responsible for maintaining and enhancing the equipment resource of the facility, and for assuring that the operational policies of the facility are followed. On matters involving equipment usage or safety, you must follow the direct instructions of the staff. Both staff and Users are expected to act in a courteous and professional manner at all times. Deviations from this norm by either students or staff should be reported to the Laboratory immediately. 3.12 TAU-MICROLAB Safety Improvement Team The TAU-MICROLAB Safety Improvement Team is organized to promote increased safety in TAU-MICROLAB operations. They review equipment installations and procedures and recommend changes to the management. .

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4.0 Equipment Use and Availability 4.1 Approved Users Access to the laboratory does not of itself permit use of any particular instrument. With few exceptions, the equipment in the facility is hands-on equipment for the users. Each major instrument is under the charge of a staff member. That staff member will train users on that instrument. When the system manager is satisfied, the user will be authorized to use the system without further supervision. Much of the equipment in the facility is highly complex and delicate. In most fabrication facilities, direct hands-on access to this type of equipment by the end-user would be severely restricted or prohibited. We view hands-on access as an important part of the educational process. Each instrument necessarily has rules and operational procedures which are set by the staff to assure the continued operation of the instrument. Violation of these procedures or carelessness in operation can result in damage to the equipment, down-time and considerable expense. Consequently, careless or damaging use of equipment will result in suspension of user privileges, either for a specific instrument or the facility as a whole. The wet chemical hoods are now treated as any other "instrument". You must be specifically trained and authorized to use them. This training and authorization is done by appointment as part of the regular orientation sequence, see section 3.3. You are required to attend these sessions on chemical safety and chemical use prior to using any chemicals in the facility. 4.2 Equipment Log Sheets Each instrument has a log book. This log is used not only for charges, but also to record system malfunctions and system status. Users must sign-in before beginning to use an instrument. All information requested on the log sheet must be provided. 4.3 Equipment Use Charges There is not formal charge system. 4.4 Scheduling Currently the scheduling is done by the lab manager only. Once the lab will be busier a more streamlined scheduling system will be implemented. 4.5 Problems Problems with equipment malfunctions, breakage, etc. should be reported to the appropriate system manager. Do not try to fix or adjust anything yourself. This equipment is very expensive and much of it is very delicate. Considerable damage can be done at a great cost of both money and downtime by careless attempts to fix things. There is no reason for any User to use a tool on anything, with the exception of a small screwdriver for sample mounting.

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Do not call the staff at home in the evenings or on weekends about minor problems with the equipment or your process. It will have to wait until the morning. Obviously, major problems like fire, smoke, or equipment alarms should be reported immediately. Any emergency involving injuries, fire, chemical spills, etc., should be reported to Tel-Aviv university authorities and to the appropriate staff.

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5.0 Laboratory Practices 5.1 Visitors Visitors are allowed to enter when accompanied with a User. Please log-in in the vititors book. 5.2 Student Storage A limited amount of storage space is available for student use in the facility. The staff periodically disposes of things left in unassigned drawers, as well as things labeled as belonging to graduated students and non-active research groups 5.3 Phones and Intercom Will be installed. 5.4 Buddy System The laboratory is open for most use 24 hours a day, every day. Some processes and equipment may not be available outside hours of the normal work week (S-T, 8 a.m.-4 p.m.). Some processes can not be run at all during off periods Other systems may be run during off hours only with the presence of another User. For the buddy system, some knowledgeable user must be in the lab to assist you in an emergency. The Buddy system particularly applies to all wet chemical use (see section 7.6.11) during off hours. Additional procedures may apply to specific instruments. You will be advised of these when you are trained on each instrument.

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6.0 Clean Room Functions

6.1 Contamination Control The primary limitation to clean room cleanliness is the people using the clean room. By industrial standards, TAU-MICROLAB has very lax clean room procedures. However, strict adherence to our rules and common sense allow us to maintain a level of cleanliness adequate for the types of work done at TAU-MICROLAB. A few obvious rules are: Do not bring anything into the clean room which is not absolutely necessary for the work you are doing. Do not wear make-up. Do not comb your hair in the clean room. Bare legs must be covered. The facility does not supply pants. Socks or Nylons must be worn along with regular shoes (no sandals) Do not use pencils or erasers in the clean room. No smoking anywhere in the Laboratory. Remove outside coats and place downstairs before entering togging room Do not wear dirty clothes, particularly muddy boots or shoes into the clean room. Unpack cardboard boxes outside the clean room. Do not take packing material inside. Newspapers may not be brought into the clean room. Clean off equipment, parts, tools, etc. before bringing them into the lab. No backpacks, canvas bags, etc. in the lab. No food and No gum. 6.2 Safety Glasses Safety glasses must be worn in the TAU-MICROLAB Clean Room. Safety glasses must be impact resistant and have side shields and be compliant with the Z87.1-1989 standard. Heavy users who normally wear prescription lenses may wish to purchase prescription safety glasses. Safety glasses may be removed for brief periods for use of optical microscopes. Safety glasses are not a substitute for Safety Goggles or Face-shields. 6.3 Clean Room Apparel Users are supposed to wear a lab coat, shoe covers and hats. 6.4 Clean Room Facilities Special ventilation equipment is used and extensive housecleaning procedures are implemented to assure some level of cleanliness in the laboratory. The level attainable is limited by the number of users using the facility, the informality of our operations, and design compromises made to reduce construction and operation costs. The clean room is nominally class 100; i.e.

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100 particles greater than 0.5 micron per cubic foot of air. This varies considerably with the activity level in the laboratory. Laminar flow benches are available for use which exhibit considerably lower particle count (near Class 10). These benches take the clean laboratory air and re-filter it within the hood. Users concerned with particulate contamination should take care to work inside the laminar flow benches as much as possible. 6.5 Other House Services Compressed dry air, laboratory vacuum, technical Nitrogen (TN2) and Pure (Process) Nitrogen (PN2) are supplied throughout the laboratory.

• Compressed air is used for pneumatic equipment. • Laboratory vacuum is used only for spinners, chucks, and vacuum tweezers. • Technical nitrogen is dry nitrogen (99.9%) obtained by Nitrogen Generator from

Compressed dry air and it is used for vacuum pump purges, vacuum pump dilution, UV lamp cooling, etc.

• Process nitrogen is clean, dry nitrogen obtained from boil-off of liquid nitrogen in our storage tank; it is used for venting vacuum systems, for vacuum pump purges, for blowing off wafers, for dry boxes, etc.

De-ionized water is available in the chemical bench in the special faucets. We continuously make the DI water, with a small storage tank . Just because DI water comes from a faucet does not mean it is free or inexhaustible, however. While thorough rinsing is needed for many processes, please do not leave DI faucets or cascade rinsers running unnecessarily. 6.6 Facilities Malfunctions and Alarms General electrical power failure obviously requires evacuation. It gets very dark in the lab. Emergency lights will provide enough light to exit in an orderly manner. It will be necessary for the staff to bring equipment back up before general laboratory use can resume. Exhaust fans and air handlers will resume automatically .

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7.0 Personal Chemical Safety 7.1 The Bottom Line on Safety Safety is an overriding concern in all TAU-MICROLAB laboratory activities. All operations must be undertaken with the safety of both the individual user and other users as the primary consideration. While it may be difficult for some to understand, operating safely is more important than getting your project done, or, in fact, than getting anything done. As a general rule, anyone violating any safety rule or otherwise compromising his or her personal safety or the safety of others will be denied access to the laboratory. Suspensions may be for a period of several weeks, months, or permanently. These suspensions are at the sole discretion of the facility management. Ignorance of the rules, lack of common sense, language difficulties, carelessness, and haste are not adequate excuses for unsafe behavior. For graduate students, violations could mean the end of your thesis. For outside users, it would mean the end of your project. 7.2 Safety Philosophy We wish to keep the laboratory an informal and friendly place to work. The staff neither wishes to make nor enforce rules unnecessarily, nor to "baby sit" users. We, like you, would rather be doing science. For the most part, rules on chemical use are formulated on the basis of basic chemical knowledge, the properties of individual chemicals, and common sense. In many cases, rules have been created in response to specific incidents of chemical misuse by users. In addition, a large volume of state and federal law covers chemical use in the workplace and disposal of waste. In spite of rules and staff supervision, primary responsibility for safety rests with the individual user. A responsible, considerate user with an understanding of basic chemistry, common sense, and an instinct for self preservation will have little trouble with our chemical rules or chemical safety. Those of you with your own laboratories elsewhere on campus may believe our rules are restrictive and unnecessary. We have several hundred users doing many different kinds of projects. The staff can only oversee operations during the normal daytime hours. Under these conditions, a few inconsiderate users can ruin the laboratory for others. Actually, those of you who have worked in the real world (i.e. a major semiconductor facility) will realize that we impose only relatively minor restrictions on your activities. A majority of problems, violations, and breakages in the laboratory are the result of haste. Graduate students are under a lot of pressure. There is only so much time and everything needs to be done by yesterday. Haste, however, makes waste, as the old saying goes. Operating under such conditions, you can waste your samples, waste time and money, get crummy results, break things, and endanger yourself and others by being careless. If you do not have time to do things correctly and safely, with adequate time for thought, please stay home. Your safety in the laboratory is determined not only by your actions but by the actions of those around you. Since the staff is in the laboratory only a small fraction of the time the facility is open, the users are often in the best position to observe the behavior of others. You are encouraged to point out rule violations immediately to the offenders, as well as to the staff at the first available opportunity. Inappropriate reactions by individuals to such corrections should

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also be reported to the staff. The access of everyone to the facility depends on maintaining a safe working environment. A series of thoughtless chemical violations or a single serious personal injury could result in punitive closing of the laboratory for weeks. We hope that peer pressure will result in conformance to safety standards where direct staff observation is not possible. We welcome your suggestions regarding safety and laboratory procedures. Please direct your comments to the suggestion box or the Laboratory Manager. Constructive suggestions are more welcome than complaints.

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7.3 Laboratory Hazards Hazards in the laboratory fall into 2 general categories. First, the facility uses a variety of compressed gases, some of which are toxic, highly toxic, corrosive, flammable, or explosive. The use of these gases is thus strictly regulated. An accident with any of these could be catastrophic. These hazards, however, can and have been minimized by the proper use of engineering controls, such as use of proper equipment, proper confinement, ventilation, sensors, purges, safety valves, etc., and by procedural controls implemented by the staff. These will be discussed more in the section on gas safety. The second, more troublesome category of hazard, concerns "ordinary" wet chemicals, i.e. the acids, bases and solvents commonly used in lithography and etching. These are "hands on" hazards and, in a multi-use facility like ours, are hard to control by engineering. Use of these chemicals is in the hands of the individual user, so to speak. It is precisely because they are considered "ordinary" by many users that they present a serious hazard. The chemicals we commonly use can cause severe burns, tissue damage, organ damage, asphyxiation, and genetic damage if improperly used. These chemicals can enter the body by inhalation, ingestion, or absorption (either directly through the skin or through gloves) and may have either long or short term health consequences. This also will be covered more in a later section. In addition, improper use of solvents can result in a major fire. "Ordinary" chemicals are thus definitely not hazard free. Users are expected to treat all chemicals with appropriate respect, an to be aware of all possible reactions which may be created, either intentionally or by accident. 7.4 Sources of Chemical Information The Materials Safety Data Sheet (MSDS), also sometimes known as OSHA Form 20, is a convenient, condensed source for information on the properties of any chemical. The MSDS must be supplied to you by the manufacturer or seller of a chemical. It contains in summary form, the chemical composition, the physical and chemical properties, toxicology data, and instructions for handling, spill control, and waste disposal. As a matter of good habit, you should read the MSDS for every chemical which you handle. Let us rephrase that, you must read the MSDS for any chemical you use in the TAU-MICROLAB. Safety data sheets for all chemicals approved for use in the laboratory are available in the togging room. Additional safety data sheets can be obtained from the Tel-Aviv Environmental Health office, or from the chemical company. The TAU-MICROLAB Chemical Hygiene Officer will not even consider the introduction of a new chemical into the laboratory until the user supplies an appropriate MSDS. The MSDS is just the starting point for safety related information. Additional books on chemical properties, toxicology, and safety are available for your use. A list of useful references is given in Appendix 1.

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Materials Safety Data Sheet The following is a reformatting of a Hoechst Celanese MSDS for AZ2131 Thinner. It is used here as an example only, and is not necessarily complete. Page 1 of 4 -------Product Identification------- Name: AZ2131 Thinner Synonyms: 2-Ethoxyethyl Acetate, N-Butyl Acetate Mixture Chemical Family: Solvent -------Hazardous Ingredients------- Ingredient Percent LD50 TWA STEL 2--Ethoxyethyl Acetate 85 5.1g/kg 5ppm - 15 g/kg 150 ppm 200 ppm N-Butyl Acetate 15 contact and inhalation hazard -------Physical Data------- Solubility in water somewhat soluble % volatile 100 Specific Gravity (water=1) 0.95 Evaporation rate < ether Colorless liquid, Characteristic odor -------Fire and Explosion Hazards------- Flash point: 116 F TAG CC Extinguishing Media Carbon Dioxide , Water, Alcohol foam or Dry chemical Special Procedures Use Self-contained Breathing Apparatus and full protective clothing Unusual Hazards: Solvent Vapors.. Emits toxic fumes under fire conditions -------Health Information------- Primary Route of Exposure Inhalation: Yes Skin Absorption: Yes Ingestion: No Also skin and eye contact with liquid and vapors Effects of overexposure 2-Ethoxyethyl Acetate: Liquid and high concentrations of vapor are eye and respiratory tract irritants and may cause kidney damage, narcosis and birth defects, increased fetal death, delayed fetal development, paralysis In studies with laboratory animals, 2-ethoxyethyl acetate caused blood effects, testicular damage and male infertility. N-Butyl Acetate:

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Skin and eye irritant, inhalation of vapors at high concentrations can cause irritation of eyes and respiratory tract as well as narcosis, systemic effects have not been conclusively shown. A single study reports n-butyl acetate to have caused teratogenic and reproductive effects in rats via inhalation; No evidence for the latter has been seen in humans. Carcinogen? IARC:No NTP:No OSHA:no -------Emergency and First Aid Procedure------- Inhalation Move victim to fresh air. Consult physician if irritation occurs Eye contact Flush thoroughly with water for 15 minutes. Get immediate medical help Skin contact Immediately remove contaminated clothing and wash affected area thoroughly with water. Consult physician if exposure is extensive or irritation occurs. Ingestion If person is conscious give water or milk to dilute stomach contents. Consult Physician Additional measures Administer oxygen if there is difficulty in breathing. -------Reactivity Data------- Chemical Stability: Stable Hazardous polymerization: Will not occur Conditions to avoid: Avoid contact with oxidizing agents Hazardous decomposition products Thermal decomposition may generate carbon monoxide and carbon dioxide -------Spill or Leak Procedures------- Wearing appropriate personal protective equipment, contain spill Ventilate area of spill or leak Remove all sparking devices or ignition sources Collect into inert adsorbent, place in suitable container -------Waste Disposal------- Dispose of or incinerate in accordance with regulations Listed as a hazardous substance, as defined in the Comprehensive Environmental Response, Compensation and Liability Act of 1980 -------Employee Protection------- Respiratory Protection Chemical cartridge respirator recommended for exposures exceeding TLV Protective clothing Clothing suitable to prevent skin contact Safety eyewear to protect against splashes.

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Rubber gloves Additional protective measures Use local exhaust ventilation Special precautions Keep away from heat, sparks and flame Store in original container Transport and store under dry conditions, tightly closed -------Transportation regulatory requirements ------- DOT Proper Shipping Name: Combustible Liquid, N.O.S. DOT Classification: Combustible Liquid UN/NA: NA 1993 Other DOT Requirements Not regulated by D.O.T. in containers less than 110 gallons -------Other regulatory controls ------- Some components may be regulated under state right to know laws. The components of this product are listed on the TSCA inventory. This product contains the toxic chemical or chemicals listed below, which are subject to the supplier notification requirements of section 313 of the Superfund Amendments and Reauthorization Act of 1986 (SARA) and the requirements of 40 CFR part 372, Component Percent CAS Number 2- Ethoxyethyl Acetate 85% 111-15-9 OSHA Physical Hazards: Combustible liquid OSHA Health Hazards Blood Toxin Eye Hazard Irritant Kidney Toxin Lung Toxin Nerve System Toxin Reproductive Toxin Skin Hazard SARA Hazard Class Acute: Yes Chronic: Yes Fire Hazard : Yes Pressure: No Reactivity: No The preceding is a reformatting of a Hoechst Celanese MSDS for AZ2131 Thinner. It is used here as an example only, and is not necessarily complete. 7.5 Terminology The following terms are often encountered when reading about the properties of chemicals and the toxicity of chemicals, for example, on the Material Safety Data Sheets or in the listed references. Simple definitions are included here to help you understand the properties of common chemicals when referring to the MSDS or other references. This is not intended to be a complete reference on Toxicology or Chemical Safety. 7.5.1 Chemical Properties Terms

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Pyrophoric chemicals spontaneously ignite in air. No source of ignition (spark) is needed. They react spontaneously when exposed to oxygen. Silane is an example of a pyrophoric gas used in the facility. Flash point The minimum temperature of a liquid at which it gives off sufficient vapor to form an ignitable mixture with air. Liquids with a flash point near room temperature can be ignited very easily during use. Exothermic Reaction A reaction which produces heat (releases energy). 7.5.2 Types of Exposure Acute Exposure As used in toxicology refers to a short term exposure. It has nothing to do with eithethe severity of the exposure or the severity of the effect. The type of exposure occurring during an accidental chemical spill is properly described as an acute exposure. Chronic Exposure As used in toxicology refers to a long term exposure. Again it has nothing to do with the severity of the exposure, the severity of the consequences, or the duration of the consequences. Chronic exposures can be the result of chemicals in the workplace, the home, or the environment. Chronic exposures are usually the result of carelessness, ignorance, or neglect, and not the result of an accident. Local Exposure Refers to exposure limited to a small area of skin or mucous membrane. Systemic exposure Means exposure of the whole body or system, through adsorption, ingestion, or inhalation. 7.5.3 Types of effects Acute effects Refers to the duration of the symptoms. Acute means symptoms lasting a few hours or days. Again, it has nothing to do with the severity of the effects. Chronic effects Are long term effects, manifested by prolonged duration and continuing injury. Local Effects Occur in a small area, at the place of contact. Systemic Effects Occur throughout the body, or at least away from the point of contact. Allergies and Hypersensitivity Are reactions by particular individuals to particular chemicals, caused by heredity or prior overexposure. Hypersensitive individuals should avoid exposure to the offending agents.

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7.5.4 Exposure Levels TLV - Threshold limit value. This is actually TLV-TWA (time weighted average) but is commonly called just TLV. It is the (averaged) level to which you can be exposed 8 hours a day, 5 days a week forever, without adverse health effects. These levels are set by ACGIH (governmental and industrial hygienists), and adopted into law by OSHA (the Occupational Safety and Health Administration). This level is most relevant to chronic (long term) background exposure to chemicals in the work place. Short term exposures in excess of TLV are thus not necessarily hazardous. This value is not particularly relevant to our laboratory situation. It is sometimes used as a guideline, since short term exposure to < TLV should be very safe. IDLH - Immediately Dangerous to Life and Health. This level represents the maximum value for which a 30 minute exposure will result in no irreversible or escape impairing effects, i.e. the maximum level which will not cause you to pass out or sustain irreversible organ damage. It is the value most appropriate to sudden, one time accidental exposures. For your information, a short table of values for relevant chemicals is listed below. Arsine 6 ppm Ammonia 500 ppm Carbon Monoxide 1500 ppm Chlorine 25 ppm Hydrogen Fluoride 20 ppm Diborane 40 ppm Phosphine 200 ppm STEL- Short Term Exposure Limit Actually TLV-STEL. Maximum concentration to which you can be exposed for 15 minutes, up to 4 times a day without adverse effects. PEL- Permissible Exposure Limit The statutory equivalent of TLV. LD50 The dose at which 50 % of those exposed will die. Separate levels apply to various modes of exposure, (inhalation, dermal, etc.). Usually expressed in terms of mg per kg of body weight; often measured for mice and rats, for obvious reasons. All these levels are approximate, with considerable inconsistency between various sources. It is obvious that one can not do well controlled experiments on human subjects. It is thus wise to be conservative in estimates using these numbers. 7.5.5 Toxic Effects Carcinogen A substance producing or inciting cancerous growth.

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Mutagen Capable of inducing mutations. Teratogen A substance causing damage or death to the fetus. 7.6 Chemical Use 7.6.1 Chemical Authorization Because of the large number of users in the laboratory, the facility keeps a close tab on chemicals used in the laboratory. Only specifically authorized chemicals may be used in the laboratory. Most standard processing chemicals have been pre-authorized; Materials Safety Data Sheets for these are located in the togging room, in an indexed notebook. No other chemicals may be brought into the facility without the specific authorization of the Chemical Hygiene Officer. The Chemical Hygiene Officer may issue approval based on a review of the MSDS and other relevant information provided by the user. Approval of new chemicals is not guaranteed; chemicals can be banned if they are too hazardous or are incompatible with other use of the laboratory. Do not show up with chemical in hand expecting instant approval. In particular, chemicals should not be brought and left in the lobby or public areas of the facility awaiting approval. Similarly, do not just leave the MSDS on the Chemical Hygiene Officer's desk. In general, you should obtain approval before buying or ordering a chemical. If you buy a chemical which is later not approved for use in the facility, that is your problem. The burden of proof is on the user to provide information that the chemical is needed and can be used safely in the laboratory. 7.6.2 Chemical Practice A little bit of common sense and courtesy when using chemicals will make the laboratory safer and make it easier for the staff to monitor chemical use. Below are a few requirements. You must label all containers (beakers, crystallizing dishes, etc.) before you use them, with your name, the chemical name (not formula or short hand), date, and time. This simple step will save the staff and users considerable time in identifying forgotten or spilled chemicals. Unlabeled chemicals and samples are subject to confiscation. Similarly, chemicals left in the hood for more than 24 hours are subject to summary disposal. This should not be taken as an authorization to leave chemicals out for 24 hours. They must be disposed as soon as you are finished. Hot or reacting mixtures may be left a reasonable amount of time to settle down. 7.6.3 Labware Clean glassware must be washed and dried after use. 7.6.4 Chemical Bench Operation The wet chemical bench (hood) where chemicals are used in the facility are not like the exhaust hoods you would find in a chemical laboratory. They are designed firstly to be clean benches,

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with laminar air flow, with only secondary consideration to ventilation and exhaust. The air flow is such that when improperly used a considerable amount of fumes can be blown into the room. First, you must work well inside the hood, away from the front edge (>1 foot back) or chemical fumes will be blown into the room. You must also not block the array of little holes near the front of the work surface. They are the exhaust holes. Do not cover these little holes with paper or foil. This disturbs the airflow in the entire hood. When properly used, you should not be able to smell chemicals outside the wet benches. Metal screen covers are available for covering sets of holes when you are handling small samples. Similarly, plastic rinsing trays can be used across the top of the sink when rinsing small samples. 7.6.5 Hot Plates While you may think hotplates are mundane, they can in fact be very dangerous when used in chemical hoods. Fires and melt down of the plastic hoods are both significant concerns. The following rules apply to hotplate use. Hot plates used for heating chemicals must be attended. You must be in the clean room and near the hot plate whenever it is plugged in. The wafer baking hot plates are not to be used with chemicals. You may not heat solvents with flashpoints of <130 F. 7.6.6 Chemical Bench Use Rules All chemical operations are to be done in the chemical/clean benches. You are expected to clean up after yourself, particularly in the wet benches. Do not leave beakers, towels, etc., or chemical or liquid residue in the wet decks. The work surface should be clean and dry when you start, and clean and dry when you leave. The next user has no idea if that puddle of clear liquid is HF or just water. Hoods must be clean, neat, and dry, before and after use. Chemicals must be approved and cannot be used until the MSDS is read and understood. Nitrile gloves are required for all chemicals. These may be the heavy green gloves or the stretch blue gloves. An exception to this rule is granted for resist processing with standard solvents and developers. You may use vinyl gloves instead of green Nitrile gloves only for standard photoresist processing. Eye Protection is REQUIRED; At least goggles for photolithography; Faceshields over safety glasses in all other hoods. Aprons are REQUIRED for chemical use in all hoods except photolithography Avoid overcrowding at the chemical benches. They have the prerogative of refusing your access. While you are working with chemicals you are busy. You shall not talk on the phone. You shall not read magazines. You may not have personal stereos or other audio-visual distractions at any time. Communication is important. Incidents must be corrected and reported on a time scale appropriate to the severity of the event. Thoroughly rinse empty chemical bottles. Running the faucet into the top for many minutes is not enough as there can be poor mixing. Please fill and dump 3 times. You should test the remaining residue using the available acid testing strips before placing in the glass trash.

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7.6.7 Chemical Storage We have very limited chemical storage for user specific chemicals. In general, you should not expect to keep special order, personal chemicals in the facility. You may also not store custom solutions (e.g. Wright etch, etc.) without staff approval. Mix only as much of these as you need each day. In most cases, the shelf life of these mixtures is very short anyway. All chemicals and particularly all special chemicals and solutions must be labeled with the arrival date and the owners name if appropriate. Chemicals older than 1 year will be periodically disposed without question.

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Table I. List of allowed chemicals (Tentative) - without prior aproval

Acids Phosphoric Hydrochloric Hydrofluoric Nitric Buffered Oxide Etch 6:1 Buffered Oxide Etch 10:1 Pre Mixed Etches Chrome etch (Cerric Ammonium Nitrate/Acetic Acid) Gold Etch (Potassium Iodide/iodine) Aluminum Etch type A (Phosphoric /acetic/nitric) Aluminum Etch type D (Phosphoric Acid/Sodium nitrobenzene sulfonate/acetic acid) Nanostrip (stabilized Piranha) Bases Ammonium Hydroxide Potassium Hydroxide Peroxides Hydrogen peroxide Solvents Acetone Methyl alcohol Isopropyl alcohol Ethanol Methyl isobutyl ketone Methyl ethyl ketone Methylene chloride Chlorobenzene 2-Ethoxyethyl acetate (cellosolve acetate) Ethylene Glycol monoethyl ether (cellosolve)

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7.6.8 Chemical Supplies Chemicals may only be transported in the rubber chemical carrying buckets. Users must not open a new bottle until the old one is empty. When you empty a chemical bottle, you must thoroughly wash and rinse it. (Rinse water may be safely disposed in the normal drain). Some chemical bottles, e.g. methylene chloride, must also be rinsed with solvent to get rid of the residue and odor. You should not be able to smell the residue. If it is a clear gallon glass bottle or a white plastic one gallon bottle it is to be put under the main sink for use as a waste bottle. Other empty, clean, rinsed, uncapped bottles (both glass and plastic) go into the GLASS waste can in the central process area (not in a normal waste basket). Do not cap them. Either way, the bottle MUST have no chemical or liquid residue in it. Custodians are not chemical waste handlers. 7.6.9 Approved Mixtures You may not arbitrarily mix chemicals together in the facility. Only specifically approved solutions can be made (table II).

Table II: Solutions Solutions Which can be Stored in Chemical Cabinets Methyl isobutyl ketone/isopropyl alcohol Toluene/isopropyl alcohol 1:5 2-ethoxyethyl acetate/ethanol 1:5 Methyl ethyl ketone/isopropyl alcohol Solutions which may be created but not stored Hydrochloric acid/Nitric acid Citric acid/hydrogen peroxide Phosphoric acid/hydrogen peroxide Ferric chloride / DI water Hydrochloric acid /Hydrogen peroxide Hydrofluoric Acid/Nitric Acid Ammonium Hydroxide and Hydrogen Peroxide 7.6.10 Pregnancy Users who believe themselves to be pregnant should discuss laboratory use with the Safety Officer as soon as possible. This need not severely restrict laboratory use but should nonetheless be discussed. (see discussion of solvents in photoresist in section 7.7.5.) 7.6.11 Buddy System A buddy system applies to the use of wet chemicals after normal working hours. This covers the time period between 4 p.m. and 8 a.m weekdays, and all day weekends and holidays. The buddy system requires that another knowledgeable user be in the facility, aware of your situation, and close enough to be of assistance if you have an accident. He need not be constantly at your side, just available and aware. The buddy must sign the chemical log sheet with you to assure us thatyou have a buddy, and to assure that he knows that he is responsible for you.

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A single limited exception to this rule is made for the use of standard lithography chemicals. You may spin resist, develop patterns, and strip resist in the standard solvents and developers in the resist rooms without a buddy present. This applies only to the common resists and developers. It is still recommended, however, that even in these cases, another person be available to assist you in the laboratory. 7.6.12 Contact Lenses Contact lenses must not be worn in the laboratory. This is standard practice in all chemical laboratories. If chemicals are splashed directly into the eye, the presence of a contact lens greatly exacerbates the problem. Even if you are not using chemicals directly or are wearing safety goggles over the contacts, contact lenses are not good in the laboratory. Solvent vapors can permeate the lenses and be held in close contact to the cornea, causing long term scarring. You should have a pair of normal prescription glasses for use in the clean room. 7.6.13 Protective Gear for Chemical Use Protective gear requirement are summarized below: Lithography Goggles are the minimum required. Face-shields may be used. Gloves must be used. Vinyl gloves are OK, but the Nitrile gloves are highly recommended. Aprons are not required. Other Laminar Flow Benches Face shields are REQUIRED , worn over safety glasses Nitrile gloves REQUIRED Aprons are required. The Nitrile gloves are chemically resistant, and are the ONLY gloves for use with acids and bases. The come in both heavy green and thin blue styles. The thin, white, vinyl gloves, while more flexible and comfortable, are not at all chemically resistant and are not to be used when working with chemicals.(except as noted in photolithography). The vinyl gloves are for use in handling wafers and vacuum parts. They are to keep your fingerprints off of things such as samples and vacuum systems. They will not keep out most chemicals. In fact, solvents can permeate the vinyl and be held close to the skin, causing even greater problems. Check Nitrile gloves for holes Wash gloves when contaminated Wash gloves before removal Wear gloves to open cabinets and sign log Wash and Remove gloves before touching anything else (door knobs, notebooks, phone, microscopes, etc.) Carrying chemicals requires one gloved hand to carry, one ungloved hand to open doors. You may keep and re-use your green Nitrile gloves, assuming you have thoroughly washed them. Don't leave them lying around, as no one else will want to use your old gloves.

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7.6.14 Emergency Response Equipment Spill control pillows are available in the laboratory for absorbing liquid chemical spills. They are located near the acid hood. Bottles of neutralization liquid are available for use on acid spills. Emergency showers and eye washes are located both in the laboratory and in the rear service corridor. Most chemical burns, particularly in the eyes, should be washed for 20 minutes before seeking further medical attention. Note that these washes have no drains; A lot of water will end up on the floor but at present we can't do anything about that. First Aid Kits are available at the end of the toggle room. Tubes of Calcium Gluconate Gel are available for application to HF burns. This should be applied promptly, but is not a substitute for medical attention. 7.6.15 Chemical Accidents You are primarily responsible for cleaning up any minor chemical spill you cause, using safe and approved procedures. You should request assistance from life safety and the staff for any significant spill. Do not dispose contaminated rags and broken chemically laden glass in the normal waste baskets. You should rinse the waste articles and bag them. Label them and leave them in the ventilated hood and seek assistance from a staff member on further disposal. For major chemical spills and for any unanticipated chemical reaction, you must evacuate the area or the laboratory and call the staff or the university authority. You must remain available to provide information . At present, the university has no general purpose emergency response team. In addition to normal emergency response, all accidents involving chemicals and all accidents involving personal injury must be reported to the facility management in writing as soon as possible after the incident. Explanations should include the nature of the event, the procedures being followed or not followed at the time, and actions required to prevent future similar incidents. In addition, for cases involving personal injury to employees, the university may require additional documentation. 7.6.16 Chemical Deliveries Delivery persons are often very cavalier about chemicals, handling bottles of toxic gases, corrosive liquids, and flammable solvents without appropriate caution. All chemical records should be handed to the lab manager. 7.6.17 Respirator Use Policy We have through the use of engineering controls tried to eliminate the sources of hazardous vapors and fumes in the lab areas. Ventilated cabinets and bunkers, ventilated waste containers and proper work procedures should keep the work area free of contamination. Respirators for personal use can be purchased with a physician application.. Different filters are required for specific classes of chemical vapors, i.e. solvents, acids, bases, etc.

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Chemical cartridge respirators are only air filters not air suppliers. They will trap or adsorb limited amounts of vapors specific to the type of cartridge installed but will not supply oxygen in an oxygen deficient atmosphere. You are not immune to being overcome by hazardous materials when using a respirator.

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7.6.18 Reminders and Final Checklist Common sense is the most valuable aid you have in working with chemicals. If you are unsure, either don't do it or ask one of the staff. It is impossible to enumerate all the rules and cautions applicable to chemical use, but here are a few more to consider, in summary. Always add acid to water. Perform all chemical operations carefully. Moving, mixing, pouring. 24 hours maximum parking of "cooling" beakers in hoods. Empty them as soon as possible. Chemicals must remain under the hoods. Move them around inside, not outside. Keep your head above the bottom of the Plexiglas guard especially when mixing, pouring, and heating. Don't leave gloves lying around- store them or pitch them. Don't sit down at the hood, it puts your face directly in the fume path. Finish open chemical bottles before opening new ones. Put the correct caps on waste bottles. There are at least two different kinds. Don't use blow guns near open chemicals. Don't use chemicals in shallow sloppy containers. Don't use plastic beakers on hot plates. Clean up after yourself and be careful.

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7.7 Specific Chemical Hazards 7.7.1 Acetone and Flammable Solvents Acetone is widely used throughout the facility. It is a very flammable solvent with a low flash point, (i.e. it can be ignited at a low ambient temperature). Because of this it presents a significant fire hazard. A spill of a gallon bottle of acetone could cause a catastrophic fire or explosion. It should not be transported except in chemical buckets. Solvents should also be handled with care in the hoods and not used near hot plates. Spilled solvent can be ignited by the hot plates. The resulting fire could easily be drawn up into the exhaust ducts, again with catastrophic consequences. Spilled solvents can react explosively with chemical oxidizers present, e.g. peroxides, nitric acid. Spilled solvents should be contained immediately with spill control pillows. Environmental Health and Safety should be called for emergency response and to assist in clean up. 7.7.2 Hydrofluoric Acid Hydrofluoric acid, HF, presents a significant hazard for personal injury. It is widely used in the lab in its pure form, diluted, and as the active component of BOE, Buffered Oxide Etch. It is used for etching silicon dioxide and particularly for stripping the native oxide prior to further processing. HF, however, is a very hazardous chemical, much more so than any ofthe other acids. Its danger comes from its effect on flesh. At the concentrations used in the laboratory, an HF "burn" is initially painless. You may not even know that you have gotten a splatter on your hands, arms, face, or in your gloves. The acid however will silently eat away at your flesh. The fluoride ion is not consumed in this process and is soluble in tissue, so the damage penetrates deeper and deeper, until it comes to the bone. About this time the excruciating pain begins. It is too late , however, to reverse the considerable tissue damage. Simple washing of an HF splash is not sufficient to prevent damage. It does not wash off; it is already dissolving you and will continue to do so until you receive medical attention specific to HF burns (including deep injections to neutralize the penetrated acid). Be sure that medical personnel know that it is an HF burn and know that it requires specific treatment. You thus have only 2 choices; 1) be absolutely certain that you don't get it on you by being very careful and wearing Nitrile gloves, apron, mask, etc, or 2) visiting the emergency room after you use it. We prefer #1. HF etches silicon dioxide very well. Therefore, it also etches glass. It must not be kept in a glass bottle, used in a glass beaker or disposed in a glass waste bottle. Plastic and teflon labware are available for this purpose. HF, like all other chemicals, must only be used in the chemical hoods. It is not acceptable to take a beaker of acid into the process area to strip a sample just prior to loading in a vacuum system.

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7.7.3 Piranha and Nanostrip Liquid piranha is a common name applied to a mixture of Hydrogen Peroxide and Sulfuric Acid (typically 1:5). It is extremely aggressive toward carbonaceous materials (e.g. flesh and photoresist residue, equally). It also removes heavy metal contamination. It is used by some users for cleaning wafers. We have difficulty disposing of this mixture, however, as the waste continues to react and decompose for a long period of time. This builds up pressure in the waste bottles causing them to burst. Also if the solution is mixed very peroxide rich, one can make unstable compounds. Therefore, we no longer make Piranha. We have available Nanostrip, a commercial stabilized version of Piranha. It should do everything that you might need Piranha for. 7.7.4 Chlorinated solvents Chlorinated solvents (chlorobenzene, trichloroethylene, and methylene chloride) are used in various resist processes. They are particularly bad for you, causing cancer, organ damage, etc. They should not be mixed with normal solvents in waste bottles. There are separate waste bottles for chlorinated solvents. As with most solvents, they can be readily absorbed through the skin. 7.7.5 Glycol Ethers Commercial photoresists and electron beam resists are dispersed in a variety of solvents. The composition of these mixtures is generally not disclosed on the bottle; you must look on the MSDS for it. One family of chemicals, the glycol ethers, commonly used in photoresists, masquerades under a variety of names. It is not often clear that many of these are the same chemical; oh, the wonders of organic chemistry nomenclature. In addition, the common trade name "Cellosolve" is often thrown in. Anyway, Methyl Cellosolve Ethylene glycol mono methyl ether 2-methoxyethanol are all the same thing. Similarly, Cellosolve Ethyl Cellosolve 2-ethoxyethanol (2EE) Ethylene glycol mono ethyl ether are all the same solvent. To further complicate things, each solvent has an acetate relative, so we have

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Cellosolve Acetate Ethyl cellosolve acetate (ECA) Ethylene glycol mono ethyl ether acetate 2-Ethyoxy ethyl acetate which are again all identical. I won't even go into the methyl cellosolve acetates or any of the butyl cellosolves. I think you get the picture. Most photoresists contain one or more of these as solvents. Members of this family of chemicals have been shown to be teratogens and have other effects on reproduction in laboratory animals. A number of recent studies funded by IBM and others have found evidence that these chemicals can lead to miscarriage and other reproductive effects. To quote from the MSDS for AZ 2131 Thinner (2 Ethoxyethyl Acetate and N-Butyl Acetate) " In studies with laboratory animals, 2-ethoyxethyl acetate caused birth defects, increased fetal death, delayed fetal development, caused blood effects, testicular damage and male infertility." The liquid and vapor are eye and respiratory tract irritants and may cause kidney damage, narcosis, and paralysis (in simple terms, it damages your kidneys, eyes, lungs and brains). Primary routes of exposure are inhalation, skin absorption, and skin and eye contact with vapors." N-butyl Acetate, the other component of this thinner, has a similar list of possible systemic effects. As with all chemicals, these are only the effects we know about. These experimental laboratory exposures were large amounts but nonetheless it is prudent to be careful with these solvents. If after reading this section, you still do not have sufficient respect for these chemicals, please go back and read it again. Many users have become sloppy with resist. Don't be!!!!! If you can smell resist in the resist room, somebody is doing something wrong!! Find out what it is and stop it. Users may have resist on their lab coats or have place resist contaminated trash in the waste basket. This is not acceptable. The conclusion is that you should be careful with the use of even these seemingly innocent chemicals, wear the proper protective equipment, and work in a well ventilated area at all times. 7.7.6 Peroxides All peroxides are highly oxidizing materials. Considerable energy can be released in their reactions with common materials. Some peroxide compounds are unstable, and can explode. We have hydrogen peroxide in the facility. Extreme care should be used in mixing solutions containing peroxides. Peroxides are incompatible with all forms of organic solvents and flammable materials.

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7.8 Chemical Waste 7.8.1 Disposal Disposal of waste chemicals is an area of great concern and often great difficulty. One only has to read the newspapers to know that it is not only a Tel-Aviv problem but also a national one. An enormous volume of government legislation regulates actions in this area. TAU-MICROLAB's policy of chemical waste is simple: Dilute thouroughly before you dispense small quantities of chemicals. All chemical waste is to be collected, consolidated, bottled and sent out as regulated chemical waste. Certain wastes by federal law, e.g. arsenic, can not be buried. Furthermore, the waste hauler will take only certain wastes. And finally, no one will handle any waste bottles which aren't accurately labeled with everything that is in them and the amount of each (That's the law folks). Chlorinated solvents (e.g. Methylene Chloride and Chlorobenzene) do not rinse well from bottles and other glassware. These items must be rinsed in isopropyl alcohol first, followed by water, to remove the reside which would otherwise stink up the lab. 7.8.2 Waste Handling All Empty Containers will be thoroughly washed inside and out. We can not dispose of unwashed containers. You made it. You get to wash it. Dilute rinse water only may go down the drain. Flowing water into the bottle is probably not sufficient. Please fill and dump several times. The residual chemical must be diluted by three or four orders of magnitude. It takes an amazing amount of rinsing !!! !!!! pH test the residue when you are done.!!!! We do not want to find bottles with liquid residue in the glass disposal container!!!. All waste goes only into appropriately labeled waste bottles. Labels are provided for all allowed solutions. You may add only the chemicals listed on the label. Do not overflow or cap tightly. Prepare a new bottle if necessary before beginning work. Waste bottles are stored only in designated areas of the hoods. The rest of the area is to be left neat, clean, and dry. Accidental spills must be diluted with large volumes of water. 8.0 Gas Safety The gases used within the facility for processing are generally supplied under high pressure from steel compressed gas cylinders. In most cases, these cylinders are housed in special gas cabinets and fitted with a variety of high purity valves, regulators and flow control devices. Gas cylinders must be treated with respect in all cases. An enormous amount of energy is stored in the compressed gas. In addition, many of these gases are toxic, or at least severely corrosive. Finally, improper use of gas cylinders and valves can result in contaminated gas and ruined samples and equipment. Compressed gas equipment in the facility is not user serviceable. Gas bottles are to be changed only by the appropriate staff members. Section 8.1 and Section 8.2 below cover some properties of the major hazardous gases used in

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the facility. This list is not necessarily exhaustive but is meant to cover the major gases and the major hazards present in the facility. 8.1 Hazardous Gases Used 8.1.1 Silane Silane (SiH4) is used for the deposition of CVD silicon nitride and silicon dioxide in the CVD system in the thin film area. Silane is pyrophoric. It spontaneously ignites in air at concentrations between 4 % and approximately 90 %. The silane gas cylinder is located in a ventilated cabinet. The bottle is fitted with a flow restricting orifice and a flow limit valve. These limit the flow of gas from the bottle so that even under catastrophic system failure the concentration is kept below the lower explosive limit. 8.1.2 Anhydrous Ammonia Anhydrous Ammonia (NH3) is a severely corrosive alkaline vapor with a pungent odor. It is shipped in the cylinder as a liquid under its own vapor pressure, approximately 9 atm. It exhibits good warning properties, with an odor threshold of 50 ppm. Although the TLV is only 25 ppm, concentrations up to 300 ppm can be tolerated for an hour. Concentrations above 3000 ppm are suffocating, causing convulsive coughing and respiratory spasm. Such exposures can rapidly be fatal. Ammonia is used in photolithography, and PECVD. 8.1.3 Liquid Nitrogen Nitrogen , a hazardous gas ??? Yes, it is true. More people die of asphyxiation by good old nitrogen than by any of the "toxic" gases discussed here. We use liquid nitrogen for many things in the laboratory. It is transferred to 160 liter dewars for cold traps, and the boil off is used for purge gas for all vacuum pumps. A large liquid storage tank is located outside the loading dock. Smaller tanks are filled on the loading dock. Procedures are posted for filling liquid nitrogen dewars. 8.2 Toxic Gas Handling and Usage Normally, we will use only one small (30 Cu Ft) cylinder of each of these gases. They are kept in a special ventilated gas cabinet in the rear corridor. All fittings on these lines are within a ventilated cabinet or co-axial tube. Any leak is thus exhausted directly, minimizing the amount which can enter the working area. Further, the gas manifolds are fitted with flow limiting orifices to limit the release rate under all conditions but catastrophic failure. The actual bottles of high toxicity are always closed when not in actual use. Furthermore, they are only used during the normal working day, when the lab manager is present. Thus barring catastrophic events (e.g. explosions) it should not be possible to have a significant toxic gas event during non-working hours. These systems all work together to 1) confine the gas to the bottle and tubes, 2) if it escapes, shut off further flow, 3) limit the rate at which it can escape, and 4) exhaust all possible escape sources out the ventilation stack. Thus, short of an explosion destroying the gas cabinet, valves

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and flow control devices, it should not be possible to get toxic gas into the laboratory work area. It is instructive, nonetheless, to calculate the possible concentrations of toxic gas in the event of such an improbable event. In the event of failure of all these systems, gas would be dispersed throughout the laboratory within a few minutes. The concentration would drop by a factor of 2 every few minutes because of continued air dilution. In such an event, there would be higher concentrations near the source until it becomes dispersed. 8.3 Toxic Gas Detection System IDLH exposure levels for various gases were given in an earlier section. Allowable exposures to the hydrides are comparable to that of many other gases commonly used. Because odor is not a reliable detector for these gases, the TAU-MICROLAB installed a sophisticated toxic gas monitoring system. Since all toxic gas lines and valves are under external ventilation this should eliminate major problems. 8.5 Toxic Gas Alarms Alarm systems includes detectors, red lamps, alarm sirens, automating calling system.

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9.0 Emergency Services

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Appendix 1. References Guide to Safe Handling of Compressed Gases, Matheson Effects of Exposure to Toxic Gases, Matheson Dangerous Properties of Industrial Materials, N. Irving Sax Chemical Handler's Guide, Larry Fluer, Inc. The Merck Index, Merck and Co. Prudent Practice for Handling Hazardous Chemicals in Laboratories, National Research Council First Aid Manual For Chemical Accidents, Marc J. Lefevre Prudent Practices for Disposal of Chemicals from Laboratories, National Research Council Handbook of Reactive Chemical Hazards, L. Bretherick Laboratory Health and Safety Handbook, R. Scott Tricoff and D. B. Walters. Handbook of Laboratory Safety, CRC Press Improving Safety in the Chemical Laboratory, Ed by Jay Young All These References are Available in the TAU-MICROLAB Library

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Appendix 2. TAU-MICROLAB StaffSpecial Responsibilities Director Prof. Yosi Shacham, tel: 8064 Lab manager Mark Oksman, tel:7926 Response: Alarm: Do call the appropriate staff immediately. Wait for staff to repair the monitor. You will be asked to evacuate later if it is not repairable in a reasonable period of time. Alarm: Fire Horn and Red Strobe Cause: Toxic gas detected Response: Evacuate immediately, away from the MOS area. Security will arrive automatically. Only Security will enter the laboratory (with self-contained breathing apparatus) for evaluation. Wait for Security and the staff to evaluate the situation. In all such cases, call the Lab Manager and the Director

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Appendix 3. Short and Simple Rules No unauthorized access No loaning of keys No waste into the drain No unauthorized chemicals No unauthorized solutions No unlabeled solutions No food No contact lenses No bare legs No chemicals in waste baskets No unwashed bottles in waste baskets No unauthorized use of equipment Be neat, Be clean, Be Safe Be courteous and clean up Wear protective gear Read Safety Data Sheets Know emergency procedures Read the signs, instructions and notices Ask if you don't understand Think before you act Short and Simple Consequences You can lose access to the laboratory for a long time if you violate any safety rule or cause injury or damage to persons or equipment. You are presumed to have read and understood everything in this manual.