GaN gains

From ultra-compact chargers in our pockets to next-generation radars, the era of wide bandgap semiconductors is accelerating innovation

- BY GAURAV PANDE

THE CEILING OF modern technology is defined by microscale systems that power it. Often driven by the dual engines of defence innovation and market demand, electronics have undergone a radical miniaturisation.

As our digital demands evolve, we are hitting a performance ceiling with silicon and an alternative has emerged: gallium nitride or GaN.

Gallium does not exist in pure form in nature. It is harvested as a sustainable low-carbon byproduct, extracted from bauxite and zinc ores. Unlike precious metals such as gold, gallium is relatively accessible and cost-effective, with global reserves estimated at over 1 million tonnes. However, market tightness and raw material fluctuation can quickly erode price stability. Pure gallium is so soft it can liquefy in a human palm; GaN is a rugged compound with a melting point of 1,600 degrees Celsius, outperforming silicon by more than 200 degrees Celsius.

GaN is also a wide bandgap semiconductor—bandgap is the energy threshold to shift a material from an insulator to a conductor. In conductors (like copper), it is zero; so electrons flow freely. In insulators (like glass), it is massive, so they don't flow. GaN's bandgap, significantly wider than silicon's, allows it to work in higher voltages without breaking down, higher temperatures without needing massive cooling systems and switch at faster speeds, reducing energy waste and allowing for much smaller components.