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.
A common point of confusion is the difference between switching speed in your phone charger and operating speed in a radar system. GaN excels in both. In power converters (like in your laptop), the transistor turns fully on and off to manage electricity. GaN can do this millions of times per second, allowing engineers to shrink bulky components like inductors and capacitors. This is why modern fast chargers are a fraction of the size of older ones. In radio frequency applications, the transistor amplifies continuous signals. There, GaN operates in the gigahertz range, which is mandatory for the millimetre-wave spectrum of 5G. This quality is specifically lucrative for advanced military sensors.
The shift to GaN is a fundamental change delivering tangible benefits across multiple sectors:
Automotive: In electric and hybrid vehicles, for battery charging and power conversion. Because GaN is more efficient, less energy is wasted as heat. This means vehicles can charge faster, travel further on a charge and use lighter cooling systems.
Telecommunications: Essential for 5G infrastructure, GaN provides the high-power density required for multiple input/multiple output antenna arrays, the backbone of high-throughput networks.
Defence and space: GaN's wide bandgap makes it resistant to radiation, which is critical for satellites and missiles. Unlike old radars that rotated mechanically, GaN-powered radars steer beams electronically, allowing them to track multiple targets instantly and resist jamming.
As of late 2025, the competition over GaN has shifted to the geopolitical stage. Because gallium is a byproduct of aluminium and zinc, the supply chain is tied to nations with strong mining industries. The US and partners, including India, Australia, Japan and the EU, have formed the Minerals Security Partnership. It focuses on capturing trace gallium from refineries in allied nations rather than relying on a single dominant global supplier.
India has transitioned from a passive consumer of electronics to a core swing producer (a producer which can adjust output quickly) in the GaN ecosystem. By leveraging domestic refineries like NALCO to recover gallium from bauxite residue, India is positioning itself for technological sovereignty in this arena.
Several key players are driving this effort:
Agnit Semiconductors: The nation’s first vertically integrated GaN startup, currently codeveloping testing subsystems for indigenous 5G and defence missions. There is already a formal MoU with the ministry of defence for strategic GaN technologies.
SCL Mohali: Undergoing a 4,500-crore modernisation with partners like Tata Semiconductor and Applied Materials to create a strategic foundry for military and space needs.
Kaynes Semicon: Recently launched India’s first commercial facility in Sanand, Gujarat, to ship high-performance power modules to global markets.
This achievement aligns with national goals of self-reliance.
Despite its immense promise, GaN research and integration faces significant engineering hurdles. The primary challenge lies in heteroepitaxy, the complex process of growing GaN crystal layers on foreign substrates like silicon or sapphire. Lattice mismatches (difference in atomic spacing between GaN or silicon/sapphire) during this growth can create atomic-level defects that trigger current collapse, a phenomenon where trapped charges temporarily restrict electron flow and degrade performance.
Furthermore, while silicon enjoys the economies of scale provided by 12-inch wafers, GaN production is largely confined to 4-inch or 6-inch substrates that will give you a higher cost-per-chip. Yet, such barriers are temporary.
Despite challenges, the outlook is clear: GaN is the foundational architecture of a high-power, high-density future. From ultra-compact chargers in our pockets to next-generation radars, the era of wide bandgap semiconductors has arrived, and is accelerating the pace of innovation.
The author holds a PhD in experimental Physics from the National Taiwan University and works at Imec Belgium with high-NA EUV lithography.