IISc Researchers Develop India's First Indigenous High-Power GaN-on-Silicon Microwave Transistor

In a significant leap for India's self-reliance in strategic electronics, researchers at the Indian Institute of Science (IISc), Bengaluru, have successfully developed a high-power microwave transistor based on Gallium Nitride (GaN) grown on a silicon platform. This achievement marks the first time such a device has been entirely designed, fabricated, and tested in India—paving the way for critical applications in defence and advanced communication technologies.

GaN-based microwave transistors are known for their ability to handle high voltages and amplify radio signals at very high frequencies. These features make them indispensable for radars, electronic warfare systems, jammers, and next-generation telecom infrastructure. However, due to their strategic significance, most GaN transistors are import-restricted and manufactured abroad, especially on silicon carbide (SiC) substrates, which are costly and less scalable.

What makes this development exceptional is that the IISc researchers have built the transistor using GaN-on-silicon technology—an alternative approach that significantly reduces cost and supports large-scale production. This method, however, is technically complex due to the challenges in growing high-quality GaN layers on silicon substrates, which have different physical properties and can cause stress, cracks, or defects in the material.

The team at IISc’s Centre for Nano Science and Engineering (CeNSE) tackled these challenges by carefully engineering the atomic structure of the material stack. They used precise layer-by-layer deposition techniques to build the transistor and achieved a power output of 8 watts at a frequency of 10 GHz—a performance level considered strategically valuable for many defence and communication applications.

A unique aspect of their approach was the manipulation of a fundamental property of GaN called polarisation. By tuning this property, they managed to eliminate the need for adding elements like carbon or iron—impurities that are usually introduced to stabilize the device but often degrade performance. This is the first time in India that microwave power transistors have been demonstrated using GaN-on-silicon without these intentional impurities.

The success of this fully indigenous project not only showcases India's growing capability in advanced semiconductor research but also lays the foundation for future home-grown technologies in the defence, aerospace, and telecom sectors. By removing the dependency on expensive imports, it opens up possibilities for affordable, large-scale production of high-frequency components that are vital for national security and digital infrastructure.

This milestone aligns with the broader goal of developing a robust and self-reliant semiconductor ecosystem in India—an effort that has gained momentum with recent government initiatives and international collaborations. As GaN-on-silicon becomes more refined and scalable, it is poised to play a transformative role in India’s high-tech future.