Jan 20, 2024

Nanostructure breakthrough for UVC LEDs ...

Silanna UV in Australia is claiming a major breakthrough for UV-C LED technology production using nanostructures.

UV-C LED devices are increasingly important for disinfection applications, water quality monitoring, gas sensing, liquid chromatography, and chemical and biological analysis. The new approach promises to make deep ultraviolet and far ultraviolet LEDs easier to make, more efficient at shorter wavelengths, and more reliable.

Silanna UV has patented a process called short period superlattice (SPSL) that overcomes many of the difficulties faced by AlGaN UV-C LED technologies. These adjust the ratio of aluminium and gallium metal in the alloy lattice to tune the light output from 340nm to 210nm. However UV-C output below 260nm requires high Al-content AlGaN, which can be limit the amount of n and p-type doping that is possible, leading to poor electrical performance.

The SPSL process uses several hundred alternating layers of AlN and GaN that allows the bandgap and conductivity to be finely tuned by adjusting the thickness of the layers.

The company has characterised devices at 235nm and 228nm using the process.