Optical transition of porous silicon prepared at different anodization temperatures

Photoluminescence, photoabsorption, and X-ray photoelectron spectroscopic study revealed that an optical transition of porous silicon from red-shift to blue-shift, and Si-2p binding energy transition from low to high at a critical anodization temperature, 343 K. Possible origin for the reverse variations happening at temperature below and above the critical temperature is discussed.