1. Can IC testing Go Wireless?
Introduction to the HOY tester
Soumalya Ghosh
(1304792)
University of Alberta
Electrical and Computer Engineering
soumalya@ualberta.ca
ECE 512 Fall 2012 Presentation

2. Outline
• Motivation
• IC testing strategies vs. VLSI technology
• Wireless testing – the new standard
– Introduction to wireless testing
• Types of wireless testing techniques
– RF Communication technique
– NF Communication technique
– Optical Communication technique
contd. …
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3. Outline (2)
• The new platform – HOY
– Introduction to the HOY tester
• The HOY approach
• HOY operation
• Advantages of HOY
• Test flow (HOY)
• Future work
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4. Motivation
• Probe card costs
• Probe card alignment issues
• Contact causes wear and tear in the chip
• Maintenance and cleaning issues of cards
• Testing is the only category of cost which
doesn’t decrease with advanced fabrication1
• Increased pin count, speed, timing accuracy
requirements
1. Semiconductor Industry Association, ITRS Report, 2003 Edition, 2003

5. IC testing strategies vs. VLSI technology
Fig. 1: Microprocessor clock rates2
2. Bushnell, Michael, and Vishwani Agrawal. Essentials of electronic testing for digital, memory, and mixed-signal VLSI circuits.
Vol. 17. Springer, 2000.

6. The scenario
Table 1: VLSI Chips – present and future3
3. D. Herrell, "Power to the Package," IEEE Spectrum, vol. 36, no. 7, pp. 46-53, July 1999

7. Wireless testing – the new standard
• Replaces conventional i/o pins in probe cards
with wireless links
• Specially suitable when pin density is very
high in the DUT
• Higher reliability due to reduced mechanical
stress
• No creation of debris
• Faster data rates possible than with cards
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8. RF Communication technique
• Also called as ‘Far Field’ communication
technique
• Transceivers are placed on the wafer
• Size overhead may result
• Provides long range
• Power supply considerations
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9. NF Communication technique
• Energy transmitted through varying EM field
(quasi-static EM field)
• Consumes low power
• Eliminates reflection issues
• More efficient than RF technology for shorter
distances
Fig. 2: Near and far fields around
RF source 9

10. Optical Communication Technique
• High frequency EM fields
• Almost immune to interference
• Exploited using LDT (Laser Direct Testing)
– Laser – metal interaction
– Photoelectron emission, etc
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11. The new platform – HOY
Developers are:
Cheng Wen Wu, Shi-Yu Huang, Po-Chiun Huang,
Tsin-Yuan Chang and Yu-Tsao Hsing,
Dept. of Computer Science, National Tsing Hua
University, Taiwan
and
Chih-Tsun Huang
Dept. of Electrical Engineering, National Tsing
Hua University, Taiwan
contd. …
Wu, Cheng-Wen, et al. "The HOY tester-Can IC testing go wireless?." VLSI Design, Automation and Test, 2006 International
Symposium on. IEEE, 2006.

12. Introduction to the HOY tester
• A novel wireless test system with enhanced
embedded test features
• Conceived in 2003, launched in 2005, called
HOY – (Hypothesis, Odyssey and Yield)
• Provides test solutions for wafer test, final test
after packaging and field tests and diagnostics
• Reduced capital investment, simplified test
flow and increased parallelism reduces cost
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13. The HOY approach
Odyssey
Hypothesis Yield
HOY
Fig. 3: The HOY approach
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14. Hypothesis
It is getting harder for the ATE :
i. to keep up with the pin count, speed and timing
accuracy
ii. to maintain reasonable cost level and satisfy
above requirements
iii. to maintain quality and yield for wafers bare dies
and packaged chips
 According to the HYPOTHESIS, we can solve
all these issues with wireless test
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15. Odyssey
• HOY is a long term project with some key
technologies still immature
• We expect the technological expertise
required for the implementation of HOY be
available sometime in the recent future
• Within 10 years time significant portion of IC
testing to go wireless
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16. Odyssey (2)
Fig. 4: HOY applications:
a) Wafer test
b) Chip test
c) Field diagnosis
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17. Yield
1. It performs wafer-level test and burn-in
2. It supports at-speed testing (by BIST)
3. It greatly improves the defect level before the
dies are packaged
However,
1. Complete BIST (and BISR) solutions
2. Stable and low cost wireless communication
3. Contactless power supply, security, pin/pad test
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18. HOY operation
Fig. 5: The HOY test system with contactless power supply
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19. Advantages of HOY
• It performs wafer level test and burn-in
• It supports at-speed testing (by BIST)
• It greatly improves the defect level before the
dies are packaged
• In conventional test flow there are redundant
tests
• Wafer level burn-in and test can be done in a
more cost-effective way
• Bottleneck in pin count is removed
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20. Test flow (HOY)
Greatly simplified test runs:
• Burn-in is done at the wafer level
• Both burn-in and wafer level tests are by BIST
• Further tests depend on packaging needs
– If packaged, final tests are done after packaging
– If not, KGD (known-good-die) should be
guaranteed up to the allowable defect level
• Final test contains pin test, basic functional
test, AC test and speed sort
Wu, Cheng-Wen, et al. "The HOY tester-Can IC testing go wireless?." VLSI Design, Automation and Test, 2006 International
Symposium on. IEEE, 2006.

21. Test flow (HOY) (2)
• For non-packaged dies all tests are completed
at the wafer level
• BISR repairs after the BIST detects any fault
• CUTs have their own BISR module in-built
Wu, Cheng-Wen, et al. "The HOY tester-Can IC testing go wireless?." VLSI Design, Automation and Test, 2006 International
Symposium on. IEEE, 2006.

22. Future work
Proposed technologies for HOY:
A. Enhanced Embedded Test Features
B. Wireless Transmission and Contactless Power
C. Test Interface and Testers
D. Protocols, ID and Security
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23. References
1. Semiconductor Industry Association, ITRS Report,
2003 Edition, 2003
2. Bushnell, Michael, and Vishwani Agrawal. Essentials
of electronic testing for digital, memory, and mixed-
signal VLSI circuits. Vol. 17. Springer, 2000.
3. D. Herrell, "Power to the Package," IEEE Spectrum,
vol. 36, no. 7, pp. 46-53, July 1999
4. Wu, Cheng-Wen, et al. "The HOY tester-Can IC testing
go wireless?." VLSI Design, Automation and Test, 2006
International Symposium on. IEEE, 2006.
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24. Questions
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