Visible Photoluminescence of Porous Si and Its Related Optical Properties

Abstract
Visible photoluminescence (PL) characteristics of porous silicon (PS) layers have been studied in relation to photoconduction and optical absorption spectra. The PS layers are formed on p- and n-type Si wafers by electrochemical and photoelectrochemical anodization in HF solutions. Some intrinsic correlations are observed between the peak wavelength of PL spectra and the anodization parameters. Other macroscopic observations show that both the photoconductivities and the fundamental absorption edges of PS layers are present in the visible region. This evidence suggests that the optoelectronic properties of PS are strongly modulated by the quantum size effect in microstructures of the PS.