This paper reports that CaSb thin films have been co-deposited on soda-lime glass substrates. The GaSb thin film structural properties are characterized by Raman spectroscopy. The Sb-A1g/GaSb-TO ratio decreases rapidl...This paper reports that CaSb thin films have been co-deposited on soda-lime glass substrates. The GaSb thin film structural properties are characterized by Raman spectroscopy. The Sb-A1g/GaSb-TO ratio decreases rapidly with the increase of substrate temperature, which suggests a small amount of crystalline Sb in the GaSb thin film and suggests that Sb atoms in the thin film decrease. In Raman spectra, the transverse optical （TO） mode intensity is stronger than that of the longitudinal optical （LO） mode, which indicates that all the samples are disordered. The LO/TO intensity ratio increases with increasing substrate temperature which suggests the improved polycrystalline quality of the CaSb thin film. A downshift of the TO and LO frequencies of the polycrystalline CaSb thin film to single crystalline bulk GaSb Raman spectra is also observed. The uniaxial stress in GaSb thin film is calculated and the value is around 1.0 GPa. The uniaxial stress decreases with increasing substrate temperature. These results suggest that a higher substrate temperature is beneficial in relaxing the stress in GaSb thin film.展开更多
We report optical and electrical properties of polycrystalline GaSb thin films which were successfully grown by co-evaporation on soda-lime glass substrates. The thin films have preferential orientation of the （111）...We report optical and electrical properties of polycrystalline GaSb thin films which were successfully grown by co-evaporation on soda-lime glass substrates. The thin films have preferential orientation of the （111） direction. SEM results indicate that the average grain size of GaSb thin film is 500 nm with the substrate temperature of 560 ℃. The average reflectance of GaSb thin film is about 30% and the absorption coefficient is of the order of 10^4 cm^-1. The optical bandgap of GaSb thin film is 0.726 eV. The hole concentration shows a clear increasing trend as the Ga-evaporation-temperature/Sb-evaporation-temperature （TGa/Tsb） ratio increases. When the Ga crucible temperature is 810 ℃ and the antinomy crucible temperature is 415 ℃, the hole concentration of polycrystalline GaSb is 2 × 10^17 cm^-3 and the hole mobility is 130 cm^2/（V·s）. These results suggest that polycrystalline GaSb thin film is a good candidate for the use as a cheap material in TPV cells.展开更多
基金supported by the National 863 Program of China(Grant No 2004AA513020)
文摘This paper reports that CaSb thin films have been co-deposited on soda-lime glass substrates. The GaSb thin film structural properties are characterized by Raman spectroscopy. The Sb-A1g/GaSb-TO ratio decreases rapidly with the increase of substrate temperature, which suggests a small amount of crystalline Sb in the GaSb thin film and suggests that Sb atoms in the thin film decrease. In Raman spectra, the transverse optical （TO） mode intensity is stronger than that of the longitudinal optical （LO） mode, which indicates that all the samples are disordered. The LO/TO intensity ratio increases with increasing substrate temperature which suggests the improved polycrystalline quality of the CaSb thin film. A downshift of the TO and LO frequencies of the polycrystalline CaSb thin film to single crystalline bulk GaSb Raman spectra is also observed. The uniaxial stress in GaSb thin film is calculated and the value is around 1.0 GPa. The uniaxial stress decreases with increasing substrate temperature. These results suggest that a higher substrate temperature is beneficial in relaxing the stress in GaSb thin film.
基金supported by the National High Technology Research and Development Program of China (No. 2004AA513020).
文摘We report optical and electrical properties of polycrystalline GaSb thin films which were successfully grown by co-evaporation on soda-lime glass substrates. The thin films have preferential orientation of the （111） direction. SEM results indicate that the average grain size of GaSb thin film is 500 nm with the substrate temperature of 560 ℃. The average reflectance of GaSb thin film is about 30% and the absorption coefficient is of the order of 10^4 cm^-1. The optical bandgap of GaSb thin film is 0.726 eV. The hole concentration shows a clear increasing trend as the Ga-evaporation-temperature/Sb-evaporation-temperature （TGa/Tsb） ratio increases. When the Ga crucible temperature is 810 ℃ and the antinomy crucible temperature is 415 ℃, the hole concentration of polycrystalline GaSb is 2 × 10^17 cm^-3 and the hole mobility is 130 cm^2/（V·s）. These results suggest that polycrystalline GaSb thin film is a good candidate for the use as a cheap material in TPV cells.
