Abstract
Device quality a-SiGe:H alloy has been developed at low substrate temperature (Ts∼180 °C), suitable for solar-cell fabrication using low flow rate of silane and germane and strong hydrogen dilution. The optoelectronic properties of a-SiGe:H films prepared with different substrate temperature and under different deposition conditions, i.e., low flow rate of source gases and with/without hydrogen dilution, high flow rate and with hydrogen dilution, low flow rate and helium dilution, are compared. It is found that both low deposition rate and strong hydrogen/helium dilution are essential to develop a-SiGe:H material with low defect density. Structural properties, midgap defect densities, and Urbach energies of the optimized and unoptimized materials are correlated with their optoelectronic properties. The results very well support the idea that there should be a fine balance between deposition rate and substrate temperature in developing low defect density materials. Quantum efficiencies of three Schottky battier devices were compared where a-SiGe:H layers have been deposited under different deposition conditions. The results show that both the hole and electron transport remains almost unaffected as Ts decreases from 250 to 180 °C.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.