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Because the wafer flat is not considered in (36)
due to simplicity, a large approximation error is
observed.
at t 2 1% is very accurate with a
very small difference. However, the
optimal GDW is also small in this
case, and, as a result, the percentage difference is shown to be large.

Conclusions
In this article, we discussed the
GDW calculation and its associated
optimal die-placement problems.
Systematic GDW computations for
all possible optimal regular placements were reported and can serve
as an effective tool for the computation of GDW and the selection of
the optimal die-placement scheme.
At the same time, a simple GDW estimation that depends on the ratio of
the longer edge of the die to the useful wafer radius was discussed. This
simple GDW estimation can achieve
a <3% estimation error compared to
conventional estimation over a wide
range of chip dimensions, which is
effective for practical cost computations in the semiconductor industry.

References

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[2] H. K. Wang and C. F. Chien, " An inversedistance weighting genetic algorithm
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[4] C.-F. Chien, S.-C. Hsu, and C.-P. Chen,
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12, no. 3, pp. 375-377, Aug. 1999. doi:
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[5] D. Du, A. Lim, and C.-T. Wu, " Wafer packing for full mask exposure fabrication, "
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[6] D. H. C. Du, I. Lin, and K. C. Chang, " On
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FA L L 2 0 2 0

Comput., vol. 42, no. 11, pp. 1382-1388,
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[7] A. B. Kahng, I. I. Mandoiu, X. Xu, and A.
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[8] R.-B. Lin, D.-W. Hse, M.-H. Kuo, and M.-C.
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About the Authors
Wing-Kong Ng (wingng@ieee.org) received his B.Eng. degree in electronic
engineering from the Hong Kong University of Science and Technology in
2020. In 2017, he published his first
academic paper in circuit design
while working at Canaan Semiconductor Ltd. He is currently a graduate
researcher at VX-power Technology
Ltd. and has two U.S. patents pending. His research interests include reconfigurable solar cell connection for
better efficiency, embedded system
for solar cell maximum power point
tracking, digital audio integrated circuit design, and field-programmable
gate array technology.
Wing-Ting Tam received her B.A
degree from Hong Kong Polytechnic
University. She is currently the contract administrator of CVX Semiconductor Pty Ltd., where she is working
on the compliance of the company
contracts and production quality.
Her research focuses on assisting
CVX engineers in performing optimization analysis to solve business,
finance, and engineering problems.
Annie Hin-Cheung Ko (anniehc
.ko@cpce-polyu.edu.hk) received her
Ph.D. degree from Hong Kong Baptist

IEEE SOLID-STATE CIRCUITS MAGAZINE

University. She is a senior lecturer
and associate division head of the
Division of Business and Hospitality
Management of the Hong Kong PolyU
SPEED. She was the recipient of the
CPCE Dean's Award for outstanding
teaching performance. She has been
an elected fellow of the World Business Institute of Australia since 2014.
Her research interests include corporate governance and optimizationbased finance analysis.
Wing-Shan Tam (wstam@ieee.org)
received her Ph.D. degree in electronic
engineering from the City University
of Hong Kong. She has been working
in different telecommunication and
semiconductor companies since 2004
and is currently the engineering manager of Canaan Semiconductor Ltd.
She has been an invited speaker for
numerous international conferences
and has served as a guest editor for
multiple international journals since
2014. She is the founding editor of
Solid-State Electronics Letters and has
served in that position since 2017. She
coauthored two textbooks published
by Wiley-IEEE. Her research interests
include multimedia signal processing
and mixed-signal integrated circuit
design and new device structure and
process development.
Chi-Wah Kok (eekok@ieee.org) received his Ph.D. degree from the University of Wisconsin-Madison. Since
1992, he has worked with various
semiconductor companies, research
institutions, and universities, including AT&T Labs Research, Holmdel,
SONY U.S. Research Labs, Stanford
University, Hong Kong University of
Science and Technology, Hong Kong
Polytechnic University, City University of Hong Kong, and Lattice
Semiconductor. In 2010, he founded
Canaan Semiconductor Ltd., a fabless
IC company that produces mixedsignal ICs for consumer electronics.
His research is focused on extensively applying signal processing techniques to improve circuit topologies,
designs, and fabrication technologies
within Canaan.

IEEE Solid-States Circuits Magazine - Fall 2020

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