Photoluminescence of porous silicon buried underneath epitaxial GaP

Abstract

Recent observations of visible, room-temperature photoluminescence in porous Si have stimulated research aimed at the realization of efficient, Si-based electroluminescent devices. To achieve electroluminescence, it may be beneficial to generate carriers with sufficient energy to populate the states of the quantum-confined Si structures. A viable method to accomplish this is to utilize a wide-band-gap heterojunction injector, such as GaP. Toward that end, we report the successful formation of porous Si buried underneath GaP islands, and we demonstrate that the buried porous Si layer exhibits strong photoluminescence (λ≊7000 Å).