Techsplained@FE: What is Gallium Nitride (GaN) and how can it replace silicon?

Once touted as the revolutionary technology that would replace silicon as it had a wider bandgap and better performance ratio, Gallium Nitride or GaN has spent the better part of the last two decades in obscurity. While the first of GaN products appeared in the market in 2006–the semi-conductor material has bee n used in electronics since the 1990s–since then product launches have been limited. However, over the last two years, GaN has been gaining popularity, with some of the biggest brands creating charging products using the technology. As prices of GaN decline, it is expected to displace silicon, especially as silicon products may be nearing their efficiency cycle.

What is GaN, and how can it replace silicon?

Remember the blue light that would come out of DVD players, that technology is GaN. One of the first applications of GaN was the production of light-emitting diodes and use in optical readers; however, over time, the usage of the material has increased. The bandgap–how well a material can conduct electricity–is much wider in the case of GaN than silicon, so these devices are more power-efficient and lose less energy. This efficiency also means that you can pack more of these in a similar area, improving performance. As the growth of silicon transistors is slowing down, GaN can serve as an alternative as it packs better performance.

Why hasn’t it been used till now?

One of the problems with GaN, like any other new technology, has been the high cost. While the costs are not as prohibitive as they used to be a few years ago–as per Lux Research, GaN would cost $1,900 for a two-inch substrate whereas silicon would cost $25-50 for a six-inch substrate–they are still high as compared to silicon. More important, company processes are more attuned to silicon products; a switch to GaN would require more research and development and surety that the products would not fail. While companies have created research labs and are working on the product, the solutions, except in the case of some use cases, are not full proof.

Where is GaN used currently, and what are its applications?

For now, GaN is gaining currency as chargers and charging devices. A GaN charger besides being more efficient than the current power bricks is much smaller. More important, as laptop batteries improve, s ingle small charger can power up all devices as it can regulate teh current flow by itself. As GaN can surive high temperatures it can also be used in cars to pack elements more closely to the engine . As the technology gets cheaper more use cases will emerge.