Silicon Photodiode QE Extended to 80% due to Surface Plasmon Resonance

OptoIQ: In a paper to be presented on the upcoming IEDM a team led by the National Nano Device Laboratories (Hsinchu, Taiwan) will report an external QE of >80% for photodiodes in the visible range. The QE extension was achieved by harnessing a local surface plasmon resonance (LSPR) effect "due to self-accumulated local electric field in these corners" of a metal pattern on top of the photodiode. Each pattern has a period of 2.4µm and unit area of 1.44µm2.