ENHANCED PHOSPHORUS DIFFUSION DURING THE GLOW-DISCHARGE DEPOSITION OFN-TYPE AMORPHOUS-SILICON HYDROGEN ALLOY

Phosphorus outdiffusion during glow discharge deposition of amorphous silicon hydrogen alloy (a-Si:H) is investigated. From the measurement of phosphorus profile using secondary ion mass spectroscopy on a doubl e layer structure (n+/i/quartz and i/n+/quartz), it is found that the thermally assisted phosphorus diffusion is negligibly small at 300-deg rees-C. However, the phosphorus diffusion is enhanced significantly af ter passivation with hydrogen plasma at the same temperature. It is pr oposed that the release of phosphorus by atomic hydrogen to form PH(x) radicals is the rate limiting step for enhanced diffusion.