EFFECTS OF OXIDATION ON ELECTRONIC STATES AND PHOTOLUMINESCENCE PROPERTIES OF POROUS SI

Oxidation states of porous Si, oxidized by oxygen excited by electron impact, have been analyzed using synchrotron radiation photoemission s pectroscopy (SR-PES), Auger electron spectroscopy (AES), and Fourier t ransform infrared (FTIR) techniques, and the relationship between the oxidation states and PL properties has been investigated. The energy b and gap, peak energy and full width at half-maximum (FWHM) of the PL s pectrum are almost unchanged throughout the oxidation process. These r esults suggest that oxygen bonding itself basically does not affect th e transition levels and that its levels are less sensitive to the surf ace states. The results of these analyses also imply that the skeletal structure of PS crystallites is important in PL mechanisms.