Saturated Defect Densities of Hydrogenated Amorphous Silicon Grown by Hot-Wire Chemical Vapor Deposition at Rates up to 150 A/s

Hydrogenated amorphous-silicon (a-Si:H) is grown by hot-wire chemical vapor deposition (HWCVD) at deposition rates (R_d) exceeding 140 Å/s (∼0.8 μm/min). These high rates are achieved by using multiple filaments and deposition conditions different than those used to produce our standard 20 Å/s material. With proper deposition parameter optimization, an AM1.5 photo-to-dark-conductivity ratio of 10⁵ is maintained at an R_d, up to 130 Å/s, beyond which it decreases. In addition, the first saturated defect densities of high R_d, a-Si:H films are presented. These saturated defected densities are similar to those of the best HWCVD films deposited at 5-8 Å/s, and are invariant with R_d, up to 130 Å/s.