CdMgTe as an Electron Reflector for MgZnO/CdSeTe/CdTe Solar Cells

CdMgTe with a 1.8-eV band gap was deposited at the back of MgZnO/CdSeTe/CdTe superstrates to create a conduction band barrier and reduce back surface recombination. To minimize CdCl
₂
passivation loss, substrate preheat time was varied. Photoluminescence, carrier lifetime, and quantum efficiency showed improvement with shorter preheat and secondary ion mass spectrometry profiles showed retention of CdCl
₂
passivation for short CdMgTe preheat. An HCl acid etch treatment and CdTe cap layer were incorporated independently after the CdMgTe on additional devices to minimize magnesium oxidation and the CdTe cap device showed initial promise with device efficiency reaching 13.1%.