RAPID SOLID-PHASE CRYSTALLIZATION OF HIGH DEPOSITION RATE HOT-WIRE CHEMICAL VAPOR DEPOSITION AMORPHOUS SILICON

摘要

Solid phase crystallization (SPC) occurs about 5 times faster in hot-wire chemical vapor deposition (HW) films than in plasma-enhanced chemical vapor deposition (PE) films. The decreased SPC time in HW films is independent of H of O concentrations, of deposition rate (2 to 110 A/s) and nanovoid density (below 0.04% up to 1.2%). The evolution of the nanovoid density and geometry during SPC was studied by small-angle x-ray scattering (SAXS) and attributed to strain minimization within the Si lattice. Stark differences in SAXS signals from PE and HW films during SPC are attributed to differences in H distributions between the two deposition techniques. Preliminary electrical results are presented for a heterojunction solar cell made from a HW a-Si:H film after SPC.