Influence of silane content on micro-structure and optical property of nc-Si:H films
1.Center of Micro/Nano Science & Technology,Jiangsu University,Zhenjiang,Jiangsu 212013,China;2.Center of Low-dimension Materials,Micro/Nano Device and System,Jiangsu Polytechnic University,Changzhou,Jiangsu 213164,China;3.Key Laboratory of New Energy Engineering,Changzhou,Jiangsu 213164,China)
Abstract:The intrinsic hydrogenated nano-crystalline silicon films of varied silane volume fraction have been deposited on the corning 7059 glass substrate by plasma enhanced chemical vapor deposition assisted with direct current bias.By Raman spectrometer,atomic force microscope and ultraviolet-visible transmission spectrometer the effects of the different silane volume fraction on the micro-structure and opticalproperty of films have been studied.The results show that when silane volume fraction increases,the crystalline size increases,whereas the crystal content decreases.The decrease of crystal content is the main cause for the decrease of the Raman peak intensity,the blue shift of peak position as well as the weakness of ordering character.The optical band-gap is in direct ratio to silane volume fraction.When silane volume fraction is equal to 1.3%,the films are deposited.Even nano-size crystals distribute regularlyand their deposition is in ordered orientation.The crystalline size and crystal content of these samples are nearly 2.6 nm and 50%.The film exhibits a large optical band-gap of 1.702 eV and a relatively high conductivity.