Low temperature growth of amorphous Si nanoparticles in oxide matrix for efficient visible photoluminescence

Abstract

We report a low temperature procedure for the fabrication of highly luminescent silicon nanoparticles in silicon-rich oxide films. A number density over 1012∕cm2 has been achieved for silicon particles of about 3nm in size by plasma-enhanced chemical vapor deposition at a substrate temperature of 30°C. Such deposits, when post-annealed at 500°C for 2 min, manifested a photoluminescence two orders of magnitude more intense than those samples grown at 250°C. Strong photoluminescence in the whole visible light range has been measured in samples prepared with this low-temperature procedure. The present results indicate the feasibility of fabricating silicon-based light-emitting devices with moderate processing temperatures.