India-made transistor – The Hindu BusinessLine

Researchers at the Centre for Nano Science and Engineering (CeNSE), IISc, have developed India’s first fully indigenous microwave power transistor based on a gallium nitride-on-silicon approach. These transistors are crucial for strategic applications such as radars, jammers, electronic warfare and telecom infrastructure, where they amplify radio waves during transmission. Most existing gallium nitride (GaN) transistors are built on costly silicon carbide (SiC) platforms and are import-restricted. The GaN-on-silicon approach offers economic advantages and scalability but comes with significant technical challenges.

The CeNSE team overcame these by growing the entire material stack at IISc and designing, fabricating and testing the transistors in-house. They achieved an output of 8W at 10 GHz — suitable for high-frequency applications. A key breakthrough was in engineering the material’s energy landscape by tuning a property called ‘polarisation’. This eliminated the need for intentionally adding carbon or iron impurities, which are commonly used in such devices to enable high-voltage operation. The atomic layer deposition process was meticulously studied and optimised, and the entire fabrication know-how was developed indigenously.

This is the first time in India that GaN-on-silicon microwave transistors have been demonstrated without any intentional carbon or iron addition, marking a significant leap toward self-reliance in advanced semiconductor technologies.