Room Temperature Growth of Hydrogenated Amorphous Silicon Films by Dielectric Barrier Discharge Enhanced CVD

摘要

Hydrogenated amorphous silicon (a-Si: H) films were deposited on Si (100) and glass substrates by dielectric barrier discharge enhanced chemical vapour deposition (DBD-CVD) in (SiH4+H2) atmosphere at room temperature. Results of the thickness measurement, SEM (scanning electron microscope), Raman, and FTIR (Fourier transform infrared spectroscopy) show that with the increase in the applied peak voltage, the deposition rate and network order of the films increase, and the hydrogen bonding configurations mainly in di-hydrogen (Si-H2) and poly hydrogen (SiH2)n are introduced into the films. The UV-visible transmission spectra show that with the decrease in SiH4/ (SiH4+H2) the thin films' band gap shifts from 1.92 eV to 2.17 eV. These experimental results are in agreement with the theoretic analysis of the DBD discharge. The deposition of a-Si: H films by the DBD-CVD method as reported here for the first time is attractive because it allows fast deposition of a-Si: H films on large-area low-melting-point substrates and requires only a low cost of production without additional heating or pumping equipment.