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interconnect level, we have developed and photonic devices are integrated onto power for autonomous vehicles with
materials and processes to minimize one single silicon chip using CMOS quantum AI to reduce fatalities to zero;
RC delays with lower resistance and fabrication techniques. While there are and 3) Eliminating cybersecurity issues.
lower capacitance redistribution layer many advantages to this technology, Quantum computers are expected
(RDL) wiring. At the system level, it including smaller size (400nm waveguide to be developed in a Moore’s law–like
can be directly assembled to both Si ICs width) and mature CMOS manufacturing fashion—every year from 50 today, to
and organic boards, without another processes, it also has many challenges about 5-10,000 by 2030. Amazon Web
layer of packaging—unlike with Si that include fiber coupling and the fact Services, Microsoft Azure, IBM, and
packages. A number of new packaging that Si doesn’t lase, requiring alternate others have already announced quantum
paradigms developed in the Georgia on-silicon light sources. offerings. Initially, quantum computing
Tech consortium include large-panel adoption will be a hybrid approach, in
processing (in excess of 500mm sizes), Quantum electronics which parts of the problem would be
development of 1-micron lithography Quantum physics has been a branch of handled by classical computing, and other
tools, low dielectric constant polymer physics for decades with many branches parts by quantum AI. Mimicking the
dielectric materials and processes with of study within it that include quantum human brain may be the ultimate AI.
a high aspect ratio of conductors with chemistry, quantum simulations, quantum
lower resistance and a high degree of machine learning, quantum algorithms, References
planarity without chemical mechanical and quantum communications. Quantum 1. R. Keys, “Physical limits of silicon
polishing (CMP), and barrier metals to computing (QC) has been a topic of transistors and circuits,” Rep. prog.
improve electromigration of closely- research for more than two decades. As physics, 68, 2701-2746, 2005.
spaced conductors. In addition, a new Moore’s Law-driven electronics begins 2. G. E. Moore, “Cramming more
3D package architecture, referred to slow down in terms of its ability to components into integrated circuits,”
to as 3DGPE, that advances 3D by provide increased computing at lower Electronics, 38(8), 1965.
embedding with ultra-short and low-RC power, scientists at companies like IBM 3. R. H. Dennard, IEEE J. Solid State
interconnections, helps achieve higher began to explore quantum devices. Circuits, SC-9, 256, 1974.
bandwidth than with Si interposers. Unlike current digital systems that are 4. P. Ruch, et al., “Toward five-
programmed with bits as data units, dimensional scaling: How density
Optoelectronic packaging either 0 or 1, quantum computers use improves eff iciency in future
Photonics has long been viewed as qubits, which can represent a combination computers,” IBM J. R&D Vol. 55(5)
providing higher bandwidth at lower of both 0 and 1 at the same time, based 151-157, 2011.
power in smaller and lighter packages on the principle of superposition.This 5. H. Moravec, “When will computer
than electronics. It is also immune to difference makes quantum computers h a r d wa r e m a t c h t h e h u m a n
electromagnetic interference (EMI). exponentially faster than cur rent brain,” J. Evol. Technology, online
The technology has been used not only mainframes and servers. transhumanist.com/Moravec.htm
for long-distance communications, In addition, quantum computers can do 6. Alexandre Ménard, I. Ostojic, M.
but also for system s to system s multiple calculations with multiple inputs Patel, D. Volz, “A game plan for
intercon nections. As elect ronics simultaneously, unlike today’s computers quantum computing,” McKinsey
reach bandwidth limits on account of that can handle only one set of inputs Quarterly, Feb. 2020.
Moore’s Law limits as described above, and one calculation at a time. With 50
optoelectronics becomes a necessary qubits, for example, the computing power Biography
solution to achieve bandwidths towards can be 2 to the power of 50. When the Rao Tummala is a Distinguished and
1Pb/s. Within optoelectronics, there industry gets to 1000 qubits that becomes Endowed Chair Professor Emeritus at
are many ways to improve bandwidth 2 to the power of 1000. Currently, qubits Georgia Tech, USA. Prior to Georgia
including multiplexing: more links per are at about 50, but even at these low Tech, he was an IBM Fellow. He has
optical channel, wavelength-division numbers, the computing power has been published about 800 technical papers and
multiplexing (i.e., an approach that uses demonstrated well in excess of the best invented technologies that resulted in
multiple wavelengths over the same supercomputers at much lower power. 100 patents. He has written seven books
medium), as well as modulation methods, Two factors driving qubits are quality including the first modern Handbook in
such as pulse amplitude modulation—an and number. Currently, the most visible packaging, Microelectronics Packaging
approach that provides more bits in the and dominant companies include IBM, Handbook (1988), and the latest undergrad
same amount of time. Microsoft, and Google. All the large textbook, Fundamentals of Device and
While there are many ways to fabricate semiconductor and systems companies are Systems Packaging (2019). He was a past
optoelectronics modules, the most known to have large internal programs [6]. President of IEEE EPS and IMAPS and
desirable technology is one that is made of Applications for quantum computing is an IEEE Fellow and member of the
silicon, as silicon is the most studied and are many and include: 1) Rapid R&D for National Academy of Engineering. Email
used in microelectronics. This is referred chemicals and pharmaceutical materials rao.tummala@ece.gatech.edu
to as Si photonics, whereby electronic with simulations; 2) Supercomputing

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