InGaN/silicon heterojunction based narrow band near-infrared detector

While InGaN devices have shown great potential as photodetectors and light emitting devices in the UV to visible range, extension of their applications to the near-infrared (NIR) region has been less successful due to challenges faced in developing high Indium content InGaN layers. Here, the authors present our results on the development of an InGaN/Silicon heterojunction structure with a > 70% In content in the InGaN layer, showing a measurable response in the NIR range. The achieved results show that the band offset between InGaN, buffer layer and Silicon interface can be used as a mean for fabrication of photodiode structures with spectral sensitivity varying with indium content. However, the authors observed that the resulting photoresponse is still a combination of photoresponses produced by absorption of photons in both InGaN and silicon materials.