Alternative to silicon chip

A transistor that uses gallium nitride (GaN) instead of silicon has been invented by Weixiao Huang, 2008 graduate from Rensselaer Polytechnic Institute in the US.

The GaN transistor, which could replace the silicon device, has reduced power consumption and improves the efficiency of power electronics systems in everything from motor drives and hybrid vehicles to household appliances and defence equipment.

“Silicon has been the workhorse in the semiconductor industry for last two decades,” Huang said.

“But as power electronics get more sophisticated and require higher performing transistors, engineers have been seeking an alternative that can perform better than silicon and in extreme conditions.”

Huang initially developed a process to demonstrate a GaN MOS (metal/oxide/GaN) interface, reasoning that engineers have known that GaN and other gallium-based materials have good electrical properties but no useful GaN MOS transistor had been developed.

In addition, Huang showed that the GaN MOSFET can integrate several important electronic functions onto one chip.

He has also designed and experimentally demonstrated several high-voltage MOS-gated FETs which have shown lower power consumption, smaller chip size and higher power density compared with a conventional MOSFET.

The new transistors can reduce energy loss, making energy conversion more efficient, he claims.

“If GaN transistors replaced many existing silicon MOSFETs in power electronics systems, there would be global reduction in fossil fuel consumption and pollution,” Huang said.

The transistors can also allow the electronics system to operate in hot, harsh and high power environments and even those that produce radiation.

“Because it is so resilient, the device could open up the field of electronic engineering in ways that were not previously possible due to the limitations imposed by less tolerant silicon transistors,” Haung said.