Characterization of hydrogenated amorphous silicon thin films prepared by PECVD

Amorphous silicon (a-Si:H) films are prepared on K9 glass substrate by plasma enhanced chemical vapor deposition (PECVD) and the substrate temperature varies from 150 to 300 °C. The gas phase processes of pure SiH4 in PECVD system were discussed. The change of grain size and morphology was characterized by atomic force microscope morphology (AFM). The influence of substrate temperature on the growth rate and the optical band gap of Si:H film were measured by spectra ellipsometer (SE). Scanning electron microscopy (SEM) was used to make sure the measurement of film thickness by SE.