Effects of annealing on GaAs/Si bonding interfaces for hybrid tandem solar cells

Abstract

Effects of annealing on GaAs/Si bonding interfaces of III-V-on-Si hybrid tandem solar cells were investigated. Using a cross sectional transmission electron microscope, an amorphous layer was observed at the interfaces of GaAs/Si junctions that had been fabricated by the surface active bonding method. The amorphous layer vanished after the annealing at 400°C. We also investigated the effects of the annealing on the current-voltage characteristics of n+-GaAs/n++-Si and p+-GaAs/n++-Si junctions.