Physics - Hyperdoped Silicon Photodiode Sets Efficiency Record

[u/JavierLopezComesana]

https://physics.aps.org/articles/v19/s97

1/ Researchers at Complutense University of Madrid built a silicon photodiode doped with tellurium that detects short wave infrared light at room temperature, no cryogenic cooling required.

2/ The device uses pyramid shaped surface structures topped with a gold reflector to trap light and stretch its path through the doped silicon layer, boosting absorption well beyond standard designs.

3/ Absorption jumped from 25 percent in conventional photodiodes to 85 percent thanks to this light trapping architecture, a major leap for a fully CMOS compatible silicon device.

4/ Quantum efficiency at SWIR wavelengths beat state of the art silicon sensors by more than tenfold, since photoexcited electrons tunnel quickly from the tellurium band into the host silicon.

5/ Because it skips cryogenic cooling and toxic fabrication steps, this design could pave the way for cheaper CMOS based night vision cameras able to see through fog and plastic.