Abstract
The addition of hydrogen gas to silane gas during the deposition of high-quality a-Si: H has frequently been reported to improve the optical and electronic responses of the material. For our preparations of device-quality a-Si: H(: D) in an r.f. glow-discharge reactor from SiH4, SiH4 + H2, and SiH4 + D2, we find no significant differences between the optical and electronic properties of the as-deposited materials. However, structural examinations by gas evolution and high-resolution transmission electron microscopy (HRTEM) reveal marked dissimilarities, the gas evolution being an especially discriminating tool. Moreover, annealing at several temperatures, followed by a full complement of optical, electronic and HRTEM measurements, demonstrates differences in the optoelectronic properties that can be reasonably correlated with the structural differences.