Electron beam induced current and cathodoluminescence study of proton irradiated InAsxP1-x/InP quantum-well solar cells

The effects of proton irradiation on strained InAsxP1-x/InP-based quantum w ell solar cells (QWSCs) have been investigated by the electron beam induced current (EBIC) and cathodoluminescence (CL) techniques. From analysis of t he EBIC data, capture rates within the quantum well region have been estima ted, from which the open circuit voltages of the cells were calculated and shown to agree well with the measured values. Diffusion lengths have been e stimated from analysis of both the EBIC and CL measurements. The location o f the energy levels of proton-induced defects and their effectiveness as no nradiative recombination centers have been determined from Arrhenius plots of the total CL intensity emitted from the quantum wells following irradiat ion. The results suggest that deeper and narrower quantum wells increase th e sensitivity of QWSCs to radiation damage. (C) 2001 American Institute of Physics.