Photoconductivity spectra of porous silicon as a function of preparation parameters

495-497<span style="font-size: 15.5pt;mso-bidi-font-size:8.5pt;font-family:" times="" new="" roman","serif""="">Photoconductivity (PC) which is controlled by non-radiative recombination could provide important information for the understanding of the transport and microscopic origin of photoluminescence (PL) and electro-luminescence (EL) of porous silicon (PS). With this, it may be possible to address the instability encountered in PS optoelectronic devices. An attempt has been made to investigate the transport properties of porous silicon by undertaking a systematic study of the influence of the anodisation parameters on photoconductivity spectra of PS, prepared by wet electrochemical anodisation of p-type c-Si. The PC peak was observed to blueshift with increasing current density/anodisation time and decreasing HF concentration, due to a decrease m crystallite size that <span style="font-size: 15.5pt;mso-bidi-font-size:8.5pt;font-family:" times="" new="" roman","serif""="">was confirmed by SEM observations. The results have been explained as a consequence of bandgap widening, according to the quantum confinement model.