Influence of Atomic Hydrogen Treatment of a Si Substrate on the Formation of and the Light Emission from Porous Silicon

Abstract

Porous silicon was prepared by electrochemically anodizing Si substrates exposed to an atomic hydrogen plasma. The hydrogen exposure was shown to result in a change in the photoluminescence (PL) emission spectra and a significant reduction in the pore size. A 30-min H exposure at 150 • C resulted in a fourfold increase in the PL intensity, a blueshift of about 60 nm in the peak emission wavelength, and a decrease in the pore diameter by a factor of 3. These results are consistent with enhanced passivation of Si dangling bond defects and enhanced hydrogenation of the Si substrate by atomic hydrogen.