特殊图案透明欧姆接触微结构提高谐振腔增强型光探测器的响应性能

Improving Resonant Cavity Enhanced Photodetector′s High Speed Performance by Transparent and Unique Pattern Ohmic Contact Microstructure

为解决谐振腔增强型(RCE)光探测器的耦合效率和响应速率的矛盾,提出了采用特殊图案透明欧姆接触的微结构及其制备工艺方案,从而使得在器件入光面积不变的情况下,欧姆接触部分的总面积显著减小,在不影响器件量子效率的前提下达到减小电容、提高响应速率的目的。在台面面积为50μm×50μm的情况下,获得了18 GHz的响应带宽。研制的谐振腔增强型光探测器的响应速率得到了显著的提高。

The scheme of the transparent and unique pattern ohmic contact microstructure was proposed and realized for the first time to overcome the conflict between coupling efficiency and response speed in resonant cavity enhanced （RCE） photodetector. This scheme can be used for reducing the devicePs diode capacitance, and not influencing device＇s bandwidth of the spectral response and the quantum efficiency. Novel RCE photodetectors with high coupling efficiency and high speed, which are based on this scheme, have been successfully fabricated. The response speed of the devices is remarkably increased; 3 dB bandwidth of 18 GHz has been demonstrated （3 dB bandwidth of 9.47 GHz without unique pattern ohmic contact microstructure） with mesa area of 50μm× 50μm.