RCEPD With Enhanced Light Absorption by Crown-Shaped Quantum Well

A high-performance resonant cavity enhanced photodetector (RCEPD) is developed by introducing an InGaAs/GaAs crown-shaped quantum well (CSQW) structure. In calculation, the absorption coefficient of the proposed CSQW structure is significantly enhanced by 47.8% compared with that of the conventional QW without increasing the electric field due to the large overlap of electron/hole-wave functions. To verify the feasibility of our proposed QW structure, we fabricate RCEPDs with a designed CSQW and the conventional QW structure. The fabricated CSQW-RCEPD exhibits a maximum quantum efficiency of 45.4%, an improvement of 36.2% in comparison with the conventional RCEPD. Moreover, the spectral bandwidth is 4.7 nm in the CSQW-RCEPD, which is in good agreement with the calculated result. The RCEPD with enhanced light absorption using a CSQW structure is highly promising for optical interconnect and sensing applications.