Study of intrinsic stress in hydrogenated amorphous silicon PECVD films with cyclohexasilane (CHS) as a precursor

PECVD remains one of the main a-Si:H thin films deposition techniques for photovoltaic applications. Recently it was reported that the electronic grade a-Si:H films can be obtained via PECVD of cyclohexasilane (CHS) as a precursor. It was found that PECVD fabricated a-Si:H films experience an internal stress, which may significantly affect the photocurrent degradation and cause delamination of the multilayer structure from the substrate. To elucidate the origin of stress in CHS-made a-Si:H films we have studied the stress variations depending on process pressure, discharge power, and hydrogen dilution. These results were correlated with the film hydrogen content, figure of merit and photo-response.