Role of hydrogen- and oxygen-terminated surfaces in the luminescence of porous silicon

Abstract

Room-temperature luminescence observed in porous silicon has been attributed either to direct radiative recombination in nanometer-size silicon in the porous silicon network, or to chemical complexes of silicon, hydrogen, and/or oxygen. In this paper, we attempt to correlate results of infrared and photoluminescence spectroscopy of freshly prepared and chemically treated porous silicon layers such that hydrogen or oxygen related species can be selectively enhanced on the surface of the porous silicon network. Our results indicate that it is difficult to establish a direct correlation between the visible luminescence in porous silicon and any particular chemical specie(s) such as silicon hydride(s), oxide, or siloxene.