Semiconductor Wafer Test Technology and Trends: Lessons for MEMS Test Engineers presentation at MEMS Testing and Reliability 3rd Annual Conference (October 20, 2011) by Ira Feldman (www.hightechbizdev.com)
12. Stimulus & Response – MEMS Sensors
MEMS Testing & Reliability Conference 2011
Electrical
Thermal
Electrical
Device
Under Test
Motion
(DUT)
Pressure
• Accelerometers
Magnetic • Gyroscopes
• Magnetic Compass
• Microphones
• Speakers
• Pressure sensors
Pressure …
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13. Stimulus & Response – Life Science + ?
MEMS Testing & Reliability Conference 2011
Electrical
Electrical
Thermal Device
Under Test Mass
Mass (DUT)
• Valves
• Pumps
Optical
• Mixers
Optical • Micro reactors
• Sensors
• Micro explosives
…
Mass include movement of material in / out of DUT such as fluids & gas. 13
14. Device Testing
MEMS Testing & Reliability Conference 2011
Device
Stimulus Under Test Response Correct?
(DUT)
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15. MEMS Testing & Reliability Conference 2011
Outline
} Market Dynamics
} Testing Semiconductors vs. MEMS
} Cost of Test
} Semiconductor Solutions
} MEMS Challenges
} MEMS @ Semiconductor Wafer Test Workshop
} Conclusion
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16. Cost of Test Drivers
MEMS Testing & Reliability Conference 2011
Increasing Tighter
test pad
frequency pitches
Increasing Increasing
transistor probe
count Increased count
Cost
16
17. Semiconductor Cost - Test Solutions
MEMS Testing & Reliability Conference 2011
Test Increased Test Lower
Reduction Parallelism Partitioning Cost
Silicon
Velocity
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22. MEMS Testing & Reliability Conference 2011
Test
Partitioning
- Increased process steps
- Increased process complexity
+ Optimized high-cost ATE
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23. MEMS Testing & Reliability Conference 2011
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“Bemo – Nemo – Remo, The Trifurcation of the ATE Industry”, Jim Healy, Sony LSI Design, ATE Vision July 2011
24. MEMS Testing & Reliability Conference 2011
Outline
} Market Dynamics
} Testing Semiconductors vs. MEMS
} Cost of Test
} Semiconductor Solutions
} MEMS Challenges
} MEMS @ Semiconductor Wafer Test Workshop
} Conclusion
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34. MEMS Testing & Reliability Conference 2011
Outline
} Market Dynamics
} Testing Semiconductors vs. MEMS
} Cost of Test
} Semiconductor Solutions
} MEMS Challenges
} MEMS @ Semiconductor Wafer Test Workshop
} Conclusion
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35. SWTW 2011
MEMS Testing & Reliability Conference 2011
"MSO - Multi-Site Optimizer"
Kevin Fredriken
(SPA GmbH - Germany)
• MEMS device alternating
rotation across wafer à
required two probe passes.
• No probe of cap or wafer
exclusion zone
• Developed four site probe card
and stepping algorithm using
MSO. Inclusive probing with
multi-probes on some die. 35
36. SWTW 2011
MEMS Testing & Reliability Conference 2011
"Probe to Pad Placement Error
Correction for Wafer Level S-
Parameter Measurements"
Steven Ortiz
(Avago Technologies - USA)
• FBAR structure – resonator plus
cap wafer.Vias through cap wafer
to resonator.
• Due to very high frequency and
tight specification tolerance, very
sensitive to location of probes
on pad. à Implemented
“calibration” structures to de-
embed the measurements.
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37. SWTW 2011
MEMS Testing & Reliability Conference 2011
"Ghosting - Touchdown Reduction Using Alternate Site Sharing"
Doron Avidar and Yossi Dadi (Micron - Israel)
When using large multisite arrays that need > 3 touchdowns / wafer, “ghosting” may save
several touchdowns. Examples showed12 to 20% savings. 37
38. MEMS Testing & Reliability Conference 2011
Summary
} Proven semiconductor cost reduction techniques
} Not always intuitive
} Require test engineering
} Can be applied to MEMS
} MEMS wafer test challenge
} Multi-site stimulus and response
} Proper probe card architectures required
} Solution integration support
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39. MEMS Testing & Reliability Conference 2011
Resources
} IEEE Semiconductor Wafer Test Workshop (SWTW)
} http://www.swtest.org
} International SEMATECH Manufacturing Initiative (ISMI)
Probe Card Cost Model
} http://ismi.sematech.org/modeling/probeCOO.htm
} SEMI E35-0307
} Guide to Calculate Cost of Ownership (COO) Metrics for
Semiconductor Manufacturing Equipment
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40. MEMS Testing & Reliability Conference 2011
Thank You!
Ira Feldman
ira@feldmanengineering.com
Visit my blog
www.hightechbizdev.com
for additional test resources.
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