Revolution Induced in Modern Inductors

Classification of inductors in modern electronics is ubiquitous. With Internet of Everything (IoE) miniaturization and new compact design factors are all revolutionizing today’s electronics.

Darwinism the fundamental component of modern electronics, a higher performing, smaller alternative to the inductor is to said have been developed using a material-based approach.

A team at UC Santa Barbara, led by Kaustav Banerjee, a professor in the Department of Electrical and Computer Engineering, has taken a materials-based approach to reinventing this fundamental component of modern electronics. The findings appear in the journal Nature Electronics.

Professor Kaustav Banerjee, leading the team at UC Santa Barbara (UCSB) in this project, explained that in typical metal conductors the kinetic inductance is so small it goes unnoticed. “The theory of kinetic inductance has long been known in condensed-matter physics,” he said. “But nobody ever used it for inductors because in conventional metallic conductors, kinetic inductance is negligible.”

Unlike magnetic inductance, kinetic inductance does not rely on the surface area of the inductor. Instead, it resists current fluctuations that alter the velocity of the electrons and according to Newton’s law of inertia, the electrons resist such a change.

Prof Banerjee explained that as the links between transistors and interconnects have advanced, the elements have become smaller, yet the inductor has remained an exception.

“On-chip inductors based on magnetic inductance cannot be made smaller in the same way transistors or interconnects scale because you need a certain amount of surface area to get a certain magnetic flux or inductance value,” lead author, Jiahao Kang, added.

Historically, as the technology of transistors and interconnects that link them has advanced, the elements have become smaller. But the inductor, which in its simplest form is a metallic coil wound around a core material, has been the exception.

“On-chip inductors based on magnetic inductance cannot be made smaller in the same way transistors or interconnects scale, because you need a certain amount of surface area to get a certain magnetic flux or inductance value,” explained lead author Kang, who recently completed his Ph.D. under Banerjee’s supervision.

The UCSB team designed a new kind of spiral inductor comprised of multiple layers of graphene. Single-layer graphene exhibits a linear electronic band structure and a correspondingly large momentum relaxation time (MRT) — a few picoseconds or higher compared to that of conventional metallic conductors (like copper used in traditional on-chip inductors), which ranges from 1/1000 to 1/100 of a picosecond. But single-layer graphene has too much resistance for application on an inductor.