Short ciruit current improvement of SiGe solar cell in a gallium arsenide phosphide - silicon germanium dual junction solar cell on Si substrate

摘要

Light trapping capability is analyzed for the SiGe solar cell in the GaAsP-SiGe tandem device. One-dimensional model predicts an achievable Jsc of 17.46 mA/cm2 below the top cell, with the electrical parameter from quantum efficiency fitting. Experimentally, a Jsc of 15.59 mA/cm2 was achieved from the Si.18Ge.82 cell, with textured SiO2 back surface reflector and a single layer SiNx anti-reflection coating. A step-by-step path to reach the 21 mA/cm2 Jsc is provided.