Improving nanoscale electrical contacts and junctions

Nov. 8, 2021

MSU research takes a step to solving shortfalls in high-tech electronics

Pity today’s electronic devices. Ever-increasing demands for smarter and more compact gadgets have pushed electronics to their physical limits. The challenges are even greater for emerging flexible and wearable electronics, where users are demanding less power consumption but more reliability and lifespan.

MSU has developed a method to help solve circuit challenges by engineering electronic components as small as one-billionth of a meter.
MSU has developed a method to help solve some of today's circuit challenges.

Research at Michigan State University has taken a step closer to reaching those high-tech goals.

Faculty members in the College of Engineering have developed a method to help solve circuit challenges by engineering electronic components that are as small as one-billionth of a meter in size.

Peng Zhang
Peng Zhang

“One of the essential building blocks are the nanoscale electrical contacts and junctions which help connect all the circuit elements to form a complete circuit,” said Peng Zhang, associate professor of electrical and computer engineering and project supervisor.

“These contacts are typically the weak points in a circuit. When the current flow is constricted, it can lead to higher electrical resistance, heat buildup, and eventually the breakdown of the circuit.”

Faulty electrical contacts aren’t limited to just small devices either, Zhang said.

“It has been estimated that contact problems account for 40 percent of all electrical/electronic failures, ranging from small scale consumer electronics to massive aerospace and military systems, and similarly threaten the operation of the Large Hadron Collider and even the International Thermonuclear Experimental Reactor (ITER),” he explained.

The MSU study, Interface Engineering of Electrical Contacts, has been published in Physical Review Applied and been awarded a U.S. Patent. (Patent # US 10,755,975 B2. https://tinyurl.com/4mb2dvwt)

Joining Zhang in the research were co-authors:

  • Sneha Banerjee, a 2021 MSU Ph.D. graduate in electrical and computer engineering, who is now a postdoc at Sandia National Lab in New Mexico, and
  • John Luginsland, a scientist at Confluent Sciences, LLC, and an adjunct professor of ECE at MSU, who recently joined the Air Force Office of Scientific Research as a program manager.
 Sneha Banerjee
 Sneha Banerjee

Zhang said the research demonstrates how to mitigate current crowding near electrical contacts by spatially engineering the interface layer properties, without requiring an additional material or component.

“The geometry of the interface is altered by ‘inserting a wedge’ to mitigate spatial variations of the current density across the interface cross section. We also find that severe current crowding in highly conductive ohmic contacts can be eliminated by introducing a thin tunneling layer or gap between the contact members.”

 John Luginsland
 John Luginsland

Zhang said their theoretical study will provide helpful insights and guidance to the electronics industry – creating the opportunity for new circuit design possibilities.