The structure and passivation effect for the c-Si wafer of a-Si:H films with different processing parameters by HWCVD

Bifacial-deposited a-Si:H films were made on n-Cz-Si with different processing parameters by HWCVD, the structure and the passivation effect of a-Si:H films were analyzed by spectroscopic ellipsometry (SE) and Fourier Transform Infrared Spectroscopy (FT-IR) with different depositing pressure, current, and distance between filament and substrate. The results show that: (1) Relative content of SiH2to SiH bond in films decreases with the pressure increasing, but decreases firstly then increases with current increasing; (2) Compare to 7.5 cm of distance between filament and substrate, the samples of 4.0 cm, proportion of the SiH2bond compare to SiH bond is higher, passivation effect is better; (3) Within the scope of this study, the passivation effect is optimal with pressure 1.5 Pa, current 21.5 A, distance 7.5 cm, surface recombination velocity 2.9 cm/s. © 2015, Chongqing Functional Materials Periodical Press Co. Ltd. All right reserved.