Sensitivity of thin film nanocrystalline silicon properties to radio frequency plasma-enhanced chemical vapor deposition (rf PECVD) parameters

Abstract

Hydrogenated nanocrystalline silicon (nc-Si:H) films for efficient nc-Si:H solar cells are made at the transition to the nanocrystalline regime during radio frequency plasma-enhanced chemical vapor deposition (rf PECVD). This transition occurs within a sensitive process window and is affected by various deposition parameters. This paper reports an investigation into the material properties of nc-Si:H films as affected by the following rf PECVD parameters: deposition power, deposition pressure, substrate temperature and silane concentration. The aim was to verify the sensitivity of nc-Si:H material properties to rf PECVD parameters. Our results showed that i-layer deposition pressure and the silane concentration mainly affected the blue response of nc-Si:H solar cells. The a-Si:H/nc-Si:H transition can be attained by manipulating any of deposition pressure, deposition power and silane concentration while keeping all other deposition conditions constant. Keywords: Nanocrystalline, vapor deposition, thin film, parameters.