Numerical Analysis and Optimization of Resonant Cavity-Enhanced p-i-n Photodiodes

摘要

Resonant Cavity-Enhanced (RCE) p-i-n photodiodes are designed to have both high bandwidth and high quantum efficiency. The RCE basic structure consists of a very thin absorption region located in a cavity where the incident radiation is forced to oscillate in order to enhance the device's quantum efficiency. In this paper quantum efficiency and frequency response are investigated for an RCE phodetector with a nonconventional p-i-n structure. The computed results enable us to devise the design rules for the device's optimization. The dependence of quantum efficiency, on wavelength and position of the absorption region in the cavity, is analyzed. The frequency response of these devices, especially when they are very thin, is determined by the capacitive effects. However they may have higher bandwidth, and therefore higher quantum efficiency-bandwidth product, than the corresponding conventional p-i-n device. The inclusion of inductive effects is seen to increase significantly the device's bandwidth.