Passivation of light-emitting porous silicon by rapid thermal treatment in NH3

The light-emitting porous silicon is treated by the rapid thermal process at 900–1100 °C under NH3 environment. The infrared absorption spectra and Auger electron spectra show that the surface of porous silicon is covered with a nitride-containing layer. From the electron spin resonance, the density of dangling bonds is found to be quite low. The photoluminescence intensity shows a slight decay under the laser illumination and remains almost unchanged after three months storage in the ambient air. All of these results illustrate that the nitride could be an effective passivation film on the surface of porous silicon.