Abstract: Using a special electrolytic cell, we prepared a series of porous silicons with different surface structures by anodizing n-type single crystal silicon in HFsolution.The surface photovoltaic spectroscopy(SPS)of the porous silicons which were formed under different conditlons was recorded.The results show that SPSof the porous silicon is obviously different from that of the non-etched silicon and the main peak wavelength has an evident blue shift relative to that of the non- etched silicon, The SPSdepends on the anodizing conditions which include HFconcentration and anodizing time.The shift is attributed to quantum confinement effects in tl1e silicon quantum wires formed in porous silicon.This observation supports the existence of the quantum size effect in porous silicon.

Key words: Porous silicon, SPS, Quantum confinement effect