The Surface Photovoltage Mechanism of a Silicon Nanoporous Pillar Array

The surface photovoltage (SPV) mechanism of a silicon nanoporous pillar array (Si-NPA) is investigated by using SPV spectroscopy in different external electric fields. Through comparisons with the SPV spectrum of single crystal silicon (sc-Si), the silicon nano-crystallite (nc-Si)/SiO sub(x) nanostructure of Si-NPA is proved to be capable of producing obvious SPV in the wavelength range 300-580 nm. The SPV for the sc-Si layer and the nc-Si/SiO sub(x) nanostructure has shown certain contrary characters in different external electric fields. Through analysis, the localized states in the amorphous SiO sub(x) matrix are believed to dominate the SPV for the nc-Si/SiO sub(x) nanostructure.