Raman scattering of polycrystalline GaSb thin films grown by the co-evaporation process  

作　　者：乔在祥 孙云 何炜瑜 刘玮 何青 李长健 

机构地区：[1]The Tianjin Key Laboratory for Photoelectronics Thin Film Devices and Technology,Nankai University

出　　处：《Chinese Physics B》2009年第5期2012-2015,共4页中国物理B（英文版）

基　　金：supported by the National 863 Program of China(Grant No 2004AA513020)

摘　　要：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.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.

关 键 词：GASB CO-EVAPORATION RAMAN stress 

分 类 号：TB383.2[一般工业技术—材料科学与工程]