Integrated Waveguide Photodetectors with Butt and Evanescent Coupling

摘要

In this paper we report on the design of an integrated waveguide photodetector designed for use in an integrated optical gyroscope with high responsivity and wide bandwidth. The butt and evanescent coupling are two common schemes for the coupling between the waveguide and the photodetector. The butt and evanescent coupling are compared, and a process flow for fabrication of such device is described. At a reverse voltage bias of −1 V, a responsivity higher than 0.6 A/W and 0.5 A/W were obtained for the butt and evanescent coupling respectively, the 3dB cut-off frequency and dark current were 55 GHz and 10 nA for both schemes.