Carrier confinement and transport in high band gap materials with embedded Si quantum dots

Silicon nanocrystals in dielectric matrices are usually produced using plasma enhanced chemical vapour deposition of Si rich Si-based dielectrics and thermal annealing at high (1100°C) temperatures. In this paper, the influence of boron doping and hydrogen dilution on the formation of Si and SiC nanocrystals in a SiC film is investigated. The dark conductivity increases from 5.4·10-8 W-1cm-1 without additional dopant gas to 2.1·10-4 W-1cm-1 with 100 sccm additional B2H6 in H2 for films annealed at 900 °C and further to 1.2·10-3 W-1cm-1 for 1000 °C annealing and 100 sccm dopant gas mixture. Furthermore, IV-curves in dark and under illumination are presented for a superlattice of 4nm Si nanocrystals and 4nm SiO2 barrier layers and are compared to those of SiC layers with Si nanocrystals