Gallium oxide to boost FET performance?

1 min read

Pushing semiconductor technology to its full potential requires smaller designs at higher energy density, according to a team from the US Air Force Research Laboratory.

“One of the largest shortcomings in the world of microelectronics is always good use of power,” said Gregg Jessen, principal electronics engineer. “Designers are always looking to reduce excess power consumption and unnecessary heat generation. Usually, you would do this by scaling the devices. But the technologies in use today are already scaled close to their limits for the operating voltage desired in many applications. They are limited by their critical electric field strength.”

The researchers are exploring the properties of transparent conductive oxides, which are said to offer the combination of conductivity and transparency over the visual spectrum. One conductive oxide has been found to have properties that could allow it to function well in power switching.

In a paper, the team outlines a case for producing microelectronics using gallium oxide and suggests that FETs could greatly benefit from the oxide’s large critical electric field strength. This, Jessen notes, could enable the design of FETs with smaller geometries and aggressive doping profiles.

“The next application for gallium oxide will be unipolar FETs for power supplies,” Jessen said. “Critical field strength is the key metric here and it results in superior energy density capabilities. The critical field strength of gallium oxide is more than 20 times that of silicon and more than twice that of silicon carbide and gallium nitride.

“From a research perspective, gallium oxide is really exciting,” Jessen concluded. “We are just beginning to understand the full potential of these devices for several applications, and it's a great time to be involved in the field.”