optical cd metrology the metro450 program...pure player in optical metrology for semiconductor...
TRANSCRIPT
Optical CD Metrology & the Metro450 ProgramShay Wolfling, PhD, Chief Technology OfficerJanuary 23rd, 2014
OUTLINE
Nova Introduction
OCD Metrology Introduction
OCD Related Challenges in Advanced Tech Nodes
Metro450 and EEM450PR Collaborations
Summary
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Founded in
1993
Employees
380
IPO in
2000NASDAQ (NVMI), TASE
HeadquartersRehovot,Israel
Global Presence
Active install base over
1300systems
Nova at a Glance
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Pure player in optical metrology for semiconductor
Strong financial indicators to support sustainable growth
Leading the emerging metrology Markets – TSV , Process monitoring
Versatile product portfolio to answer advanced metrology requirements
Continuous R&D investment to match customers’ roadmap
Nova’s Fundamentals
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What is Nova Doing?Optical metrology & process control of semiconductor manufacturing, by measuring critical‐dimensions, using spectral reflectometry
Hardware: Multi‐Channel Spectral
Reflectometry
Output: Various spectra
High‐Power Computation for advanced model‐fitting
Result: full “device model”
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Profile metrology of critical device dimensions, by optical techniques
What: Dimensions, thicknesses and optical properties
Why: Correlate to final performance and improve process How: Optical Scatterometry
Optical CD (OCD) Metrology
Same View Using Optical CD
22nm Tri‐Gate viewUsing Electron Microscope
Optical Scatterometry
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What is Scatterometry (Spectral Reflectometry)?
Optical metrology for measuring small periodic structures
Configuration: ‐ Illuminate the sample (wafer)‐ Interference in the sample ‐ Collect reflected (scattered) spectra
Reflected light contains information about sample shape & materials
Shape details are extracted by fitting a “physical model” of the device to the measured spectra
Can detect sub‐nm changes in repetitive structures
Light Source
Spectral Analyzer
Wafer
RotatablePolarizer
λ
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Modeling: From Spectrum to Device DataFitting a modeled spectrum to a measured spectrum
Periodic Structure
Actual Sensor
Parameterized Profile Model
CalibratedSensor Model
ModelMeasurement
Difference >
Tolerance
Compare
Report Profile Parameters
Update Profile Parameters
No
Yes
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Advanced Tech‐Nodes: OCD Challenges Continuous shrink
‐ Driver: Power, speed & cost ‐ Performance specifications shrink Precise Metrology and more sampling
Vertical integration – device complexity:‐ Drivers: Higher Density; Better performance per unit power‐ Devices: FinFET (Logic), Vertical NAND (Flash Memory)‐ Challenges: More parameters, High correlations
Novel material & technologies:‐ Drivers: Increased mobility (Speed & Energy saving)‐ Challenges: Complex & varying optical properties
Tighter process spec and shorter time to Metrology:‐ Measure “Closer to the Process”
IntegratedMetrology
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450 Collaboration to Answer The Challenges
Challenge Collaborative Activity
Continuous ShrinkSmart sampling (Metro WP #2)
Unique Test & Calibration Targets (Metro WP #4; 450PR D.6.3.1)
Device Complexity Fast Data collection & Processing (Metro WP #5; 450PR D.6.1.1)
Novel MaterialsUnique Test & Calibration Targets (Metro WP #4; 450PR D.6.3.1)
Fast Data collection & Processing (Metro WP #5; 450PR D.6.1.1)
Tighter specs & Shorter Time
Metrology closer to the process – Integrated Metrology & Self Diagnostics
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Collaborative work:‐ Set of generic “metrology” algorithms‐ Examine new HW architectures ‐ Demonstrate improvement in computation power
New architectures proved better than traditional solutions. The set of algorithms is now extended and new architectures are being considered
The work is done in collaboration with the Technion, AMIL, Intel, Jordan valley Mellanox as well as TNO in EMM450PR
Fast Computation Challenge
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OCD Challenging Future Applications in the 450mm Era
Customer targets are sensitive to system parameters Need to “calibrate” various system elements:
‐ Target sensitive to focus‐ Target sensitive to XY position‐ Target sensitive to Azimuth‐ Target sensitive to Tilt
Develop wafer with unique test targets to separate tool issues from sample / application problems
Calibration Wafer / Targets
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Calibration Wafer / Targets @ Metro450
Mask design
Target design Target image
after production
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Drivers:‐ Tight process specs‐ Higher wafer cost‐ Wafer‐shift complexity and risk,
Need: closer “interaction” between metrology and process tools Implications:
‐ Metrology closer to the process ‐ Integrated Metrology & InSitu Metrology‐ Requires Standardization in 450mm‐ Autonomous tool Data integration – Ability to receive and analyze, on‐the‐fly, data coming from external sources along the fabrication process and turn it into capability to improve process control
Self‐Diagnostics – Integrate tool’s sensors information into useful data to better monitor tool health (diagnostics), and improve its quality
To be addressed in future activities
Process & Metrology
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OCD will remain a significant metrology in the foreseeable future
Key challenges of OCD increase with the advancement of the technology node, and further increase with the move to 450mm
Joint work in the Metro450 and EEM450PR helps alleviate some of these key challenges in the pre‐competitive stage
Collaborative work with leading metrology companies and advanced academy researchers is essential in order to prepare for this industry infliction point
Summary
Thank You