Tech Tuesday: Mohamed ElKabbash innovates to cool CMOS chips

University of Arizona inventor Mohamed ElKabbash has developed an advanced radiative cooling system for complementary metal-oxide-semiconductor (CMOS) chips with minimal change to the chip design (see UA24-095, this invention’s technology identification on the TLA Inventions website). 

CMOS chips were invented by Frank Wanlass and commercialized by RCA in 1966. Today CMOS chips are the semiconductor chips found in smartphones. Because they tend to heat up, these chips are traditionally cooled via conduction and face heat management problems, as placing several transistors and electrical elements near one another can create “hot spots.” Additionally, chips that are 3D-integrated, or stacked on top of one another to save space, can create additional heat. 

The advanced radiative cooling system ElKabbash created converts the wires of CMOS chips to antennas that radiate heat, incorporating metal-optic layers directly into the chip’s architecture within bulk CMOS foundry processes and enhancing cooling efficiency while maintaining the chip’s structural integrity and performance. The wires can also be co-designed to carry information in the form of electrons.

ElKabbash, assistant professor in the Wyant College of Optical Sciences at the U of A, compares the proposed cooling system to how the earth cools itself. “Metals on their own are actually one of the poorest thermal radiators. They don’t radiate heat well,” he said. “But if you create an antenna with the wires that have infrared radiation, they become very efficient thermal emitters.”

Prior to receiving a Ph.D. in physics from Case Western Reserve University in 2017, ElKabbash earned multiple degrees in non-scientific fields, such as an undergraduate degree in economics from Illinois Wesleyan University and a master’s degree in public law and political economy from Alexandria University. His initial career path was informed by the difficulties of pursuing a career in science in Egypt, as well as his family’s background in law. However, he says that he always wanted a career in science, dreaming of becoming a professor and running his own lab, and decided to study “economics as a segue to physics.”

According to ElKabbash, his undergraduate in law and political economics has informed his understanding of the kinds of problems he wants to solve through innovations in photonics. “Some of my inventions were inspired by geopolitics,” ElKabbash said. “It helped me understand better how the world functions on a scale that is not necessarily what program managers want or what other colleagues are doing. I have my own take on what problems need to be solved, which makes me sometimes work in fields that no one else is working on because I’m motivated by different problems that are generated from my affinity for humanities, law, politics and economics.”

Since joining the U of A in 2023, ElKabbash has become one of the university’s most prolific inventors. Some of ElKabbash’s other active technologies available to license include a novel approach to integrating metasurfaces with standard CMOS processes (UA24-096) and a suspended nanomembrane-based EUV lithography system with diffractive optical elements and transmission masks (UA24-164). For more information about these and related technologies available for license, contact Rich Weite, Sr. Licensing Manager for the College of Optical Sciences.