dilbert. did research and learned about several communication devices – cellular phones,...
TRANSCRIPT
DILBERTDILBERT
• Did research and learned about several communication Did research and learned about several communication devices – cellular phones, Bluetooth/Wi-Fi, and RFID devices – cellular phones, Bluetooth/Wi-Fi, and RFID • Received silicon wafer to be used as base for antennas – Received silicon wafer to be used as base for antennas – could use other substrates if equipment was availablecould use other substrates if equipment was available• Received a traveler defining the steps necessary to Received a traveler defining the steps necessary to fabricate your antennafabricate your antenna•Cleaned silicon wafers to provide a contamination free Cleaned silicon wafers to provide a contamination free surfacesurface• Grew SiOGrew SiO22 (silicon dioxide) to provide an insulating (silicon dioxide) to provide an insulating dielectric surface dielectric surface • Determined your application, either cellular, Bluetooth/Wi-Determined your application, either cellular, Bluetooth/Wi-Fi, or RFIDFi, or RFID• Determined how to find the correct length for the antenna Determined how to find the correct length for the antenna based on the applicationbased on the application• Using a decision matrix determined the conductor to be Using a decision matrix determined the conductor to be used to fabricate the antennaused to fabricate the antenna• This week will deposit conductor of choiceThis week will deposit conductor of choice
Summary of Project to DateSummary of Project to Date
Thin Film DepositionThin Film Deposition
Conductors are deposited using a Conductors are deposited using a vacuum chambervacuum chamber
The vacuum chamber reduces the The vacuum chamber reduces the atmosphere to high vacuum levels (no atmosphere to high vacuum levels (no atmosphere)atmosphere)
This reduces contaminating the films, This reduces contaminating the films, provides a non-contaminating provides a non-contaminating environment free of oxygen, water environment free of oxygen, water vapor, etc. and allows materials to vapor, etc. and allows materials to melt at lower temperatures.melt at lower temperatures.
Thin Film DepositionThin Film Deposition
Thin film deposition tools are very Thin film deposition tools are very complex due to the need to create complex due to the need to create high vacuum levels.high vacuum levels.
Vacuum levels of 5x10Vacuum levels of 5x10-7-7 torr and torr and better are typical. Sea level better are typical. Sea level atmospheric pressure is about 740 atmospheric pressure is about 740 torr or 7.4x10torr or 7.4x102 2
Because of their complexity, vacuum Because of their complexity, vacuum chambers are very expensive. chambers are very expensive.
Thin Film DepositionThin Film Deposition To achieve high vacuum levels, several types of To achieve high vacuum levels, several types of
vacuum pumps are used.vacuum pumps are used.1.1. Mid level vacuum levels (2x10Mid level vacuum levels (2x10-3-3 torr) are reached with torr) are reached with
rotary vane vacuum pumps. These pumps are also rotary vane vacuum pumps. These pumps are also know as mechanical or roughing vacuum pumpsknow as mechanical or roughing vacuum pumps
2.2. High level vacuum levels are reached usingHigh level vacuum levels are reached using Diffusion vacuum pumps – requires liquid nitrogen to Diffusion vacuum pumps – requires liquid nitrogen to
prevent oil contaminationprevent oil contamination Turbomolecular pumps – like a small jet engine, clean Turbomolecular pumps – like a small jet engine, clean
and fast, good for processes that require the introduction and fast, good for processes that require the introduction of a process gas. Because of the high speed vanes, of a process gas. Because of the high speed vanes, subject to catastrophic failuresubject to catastrophic failure
Cryogenic vacuum pumps – uses low temperature (10Cryogenic vacuum pumps – uses low temperature (10ooK) K) – also clean and fast pumping but requires regeneration – also clean and fast pumping but requires regeneration periodically which is time consumingperiodically which is time consuming
Thin film deposition tools in the ECE Thin film deposition tools in the ECE Microelectronics Clean RoomMicroelectronics Clean Room
CVC 601-sputter deposition
Varian 3125 e-beam deposition
CHA Mark 50 e-beam deposition
Cooke-thermal deposition
Conductor DepositionConductor Deposition The Cooke thermal evaporator is not The Cooke thermal evaporator is not
currently used.currently used. The CVC sputter tool is used only for The CVC sputter tool is used only for
aluminum depositions. Only an aluminum aluminum depositions. Only an aluminum target is available.target is available.
The Varian 3125 and CHA Mark 50 e-beam The Varian 3125 and CHA Mark 50 e-beam deposition tools are used for all other deposition tools are used for all other conductors, Cu, Au, Ag, Cr, Ni conductors, Cu, Au, Ag, Cr, Ni – An e-beam evaporates material, it get the An e-beam evaporates material, it get the
material so hot it becomes a gas and material so hot it becomes a gas and evaporates. It then travels in a straight line, evaporates. It then travels in a straight line, because it is under vacuum, until it condenses because it is under vacuum, until it condenses when it strikes a colder surfacewhen it strikes a colder surface
With sputtering, an Argon plasma is formed, With sputtering, an Argon plasma is formed, causing argon ions to strike a metal target causing argon ions to strike a metal target
and knock loose material. Because an and knock loose material. Because an electric field is created, material is deposited electric field is created, material is deposited
on the substrateon the substrate
Material target
Argon plasma – ionized argon in an electric field
Substrate to be coated
E-beam Evaporation uses a high energy electron beam to vaporize (change from a solid to vapor)
materials, especially metals
Overall view of the Varian 3125 Overall view of the Varian 3125 vacuum chamber. This tool vacuum chamber. This tool
deposits thin films using e-beam deposits thin films using e-beam evaporationevaporation
Portion of Varian 3125 control Portion of Varian 3125 control rackrack
Varian 3125 quartz heater controller, Varian 3125 quartz heater controller, shutter controller and planetary shutter controller and planetary
rotation controllerrotation controller
Planetary (wafer holder) rotation controller
Quartz heater
controller
E-beam shutter
controller
Electron beam power supplyElectron beam power supply
Typically 6-8KV are required to form the
electron beam
Electron beam can be steered by
magnetic fields
Cryopump temperature-must be
below 15oK
Varian 3125 ion gauge Varian 3125 ion gauge controller and deposition controller and deposition
controllercontroller
Ion Gauge controller Deposition controller
Varian 3125 view of open Varian 3125 view of open chamberchamber
Wafer planetary – can rotate or stay stationary. Can be
removed for loading
Varian 3125 4-pocket e-beam Varian 3125 4-pocket e-beam cruciblecrucible
With an e-beam (electron beam) evaporator With an e-beam (electron beam) evaporator the material is heated to a vapor (gas) and the material is heated to a vapor (gas) and
then condenses on cooler surfacesthen condenses on cooler surfaces
Molten material hot enough to vaporize (become a gas)
Electron beam is
formed and strikes the
metal crucible
Substrates (wafers) sit at the top of the
chamber
Varian 3125 wafer planetaryVarian 3125 wafer planetary
Wafer planetary for Varian 3125
Varian 3125 Varian 3125
Wafers are held down by spring clips
Varian 3126 Quartz HeatersVarian 3126 Quartz Heaters
Varian 3125 door showing Varian 3125 door showing glasds slide holderglasds slide holder
Glass slide must be replaced before each run
Overall view of the CHA Mark 50 Overall view of the CHA Mark 50 vacuum chamber. This tool vacuum chamber. This tool
deposits thin films using e-beam deposits thin films using e-beam evaporationevaporation
Inside of CHA Mark 50 chamber Inside of CHA Mark 50 chamber showing wafer platen – can not showing wafer platen – can not be removed from the chamberbe removed from the chamber
CHA Mark 50 wafer adapter CHA Mark 50 wafer adapter ringring
Adapter rings are available for 2”, 3” and 4” wafers
Adapter ring for 4”/100mm
wafer
CHA Mark 50 4-pocket e-beam CHA Mark 50 4-pocket e-beam cruciblecrucible
Four different materials are available to do
sequential evaporations
CHA Mark 50 crucible materials CHA Mark 50 crucible materials and chamber temperature and chamber temperature
monitormonitor
Materials currently inside the 4 pocket crucible are shown with their pocket
number
Pocket is chosen using this indexer
CHA Mark 50 crystal oscillators for CHA Mark 50 crystal oscillators for evaporation material thickness evaporation material thickness
measurementmeasurement
Crystal oscillators
New glass slides must be used for each evaporation
CHA Mark 50 cryo-pump CHA Mark 50 cryo-pump controlcontrol
Cryogenic pump temperature – should be less than 15oK
CHA Mark 50 vacuum gauge CHA Mark 50 vacuum gauge controllercontroller
Vacuum chamber pressure of 7.5 x 10-7 torr
CHA Mark 50 E-beam power CHA Mark 50 E-beam power supply and controllersupply and controller
Power supply is interlocked to prevent activation if vacuum pressure, cooling
water, and zero current conditions are not met
Power supply main on/off switch
High voltage switch
and current control
E-beam evaporationE-beam evaporation
Crucible being heated by an electron beam
Overall view of the CVC vacuum Overall view of the CVC vacuum chamber. This tool deposits thin chamber. This tool deposits thin
films using “sputtering”films using “sputtering”
CVC sputter tool with chamber CVC sputter tool with chamber lid openlid open
Wafers are loaded into
position
Looking into the CVC sputter tool Looking into the CVC sputter tool chamber, showing the 8” aluminum chamber, showing the 8” aluminum
targettarget
CVC sputter tool control CVC sputter tool control racksracks
Ion gauge
Cryo pump temperature – must be below 16oK
Argon MFC – 30 sccm flow typical
CVC sputter tool DC power CVC sputter tool DC power supply for aluminum targetsupply for aluminum target
DC Voltage about 4KVDC current 0.5 to 1.0 A
CVC sputter tool view portCVC sputter tool view port
View of argon sputter plasma View of argon sputter plasma in CVC sputter toolin CVC sputter tool
View of argon plasma in AJA View of argon plasma in AJA sputter toolsputter tool
Sputter target
Shutter
Substrate (wafer) stage
Wafer stage can rotate and heat
Homework AssignmentHomework AssignmentDue next class meetingDue next class meeting
Review “Mask design steps” from web siteReview “Mask design steps” from web site Read “Designing Antennas for Cellular Telephones” from web Read “Designing Antennas for Cellular Telephones” from web
site.site. Find “AutoCad” on Mosaic – listed under Mechanical Find “AutoCad” on Mosaic – listed under Mechanical
Engineering as AutoCad 2006Engineering as AutoCad 2006 Become familiar with AutoCad. There is a tutorial on my web Become familiar with AutoCad. There is a tutorial on my web
sitesite Begin preliminary dimension sketches for your antenna designBegin preliminary dimension sketches for your antenna design
Maximum size 20mmx20mm Maximum size 20mmx20mm Minimum size 5mmx5mmMinimum size 5mmx5mm Line width – 1mm Line width – 1mm Spacing between lines – 1mm or greaterSpacing between lines – 1mm or greater No sharp cornersNo sharp corners Must be able to fit inside a box to allow cutting into individual antennaMust be able to fit inside a box to allow cutting into individual antenna Length must match your design lengthLength must match your design length Can be any design – be creativeCan be any design – be creative
Dimension drawing of your design is requiredDimension drawing of your design is required
Simple spiral designSimple spiral design
Cingular Logo designCingular Logo design
XBOX design XBOX design Note-DO NOT USE WHITE ON Note-DO NOT USE WHITE ON
BLACBACKGROUNDBLACBACKGROUND
Football Design- DO NOT USE WHITE ON Football Design- DO NOT USE WHITE ON DARK BACKGROUNDDARK BACKGROUND
UNC-Charlotte Crown designUNC-Charlotte Crown design
Dimensions not in a contrasting Dimensions not in a contrasting colorcolor