退火Cu2O薄膜的结构及光学特性  

Structure and optical properties of annealed Cu_2O thin films

作　　者：自兴发 黄文卿[1] 刘瑞明[1] 叶青[1] 程满[1] 孙坤[1] 

机构地区：[1]楚雄师范学院物理与电子科学学院,材料制备与力学行为研究所,云南楚雄675000

出　　处：《光电子．激光》2015年第10期1931-1936,共6页Journal of Optoelectronics·Laser

基　　金：国家自然科学基金联合资助基金(U1037604)资助项目

摘　　要：采用射频(RF)磁控溅射单质金属铜(Cu)靶,在O2和Ar的混合气氛下制备了Cu2O薄膜,并在N2气氛下对预沉积的Cu2O薄膜进行快速光热退火(RTA)处理,研究了衬底温度及退火温度对Cu2O薄膜的生长行为、物相结构、表面形貌及光学性能的影响。结果表明,衬底温度在300℃以下预沉积的Cu2O薄膜为非晶薄膜,退火处理对Cu2O薄膜的结晶行为有明显影响,在N2气氛下对Cu2O薄膜进行退火处理不影响薄膜的物相结构;预沉积和退火Cu2O薄膜在650nm以下波长范围内均有较强吸收,吸收强度随退火温度的增加而增强,薄膜在400nm以下波长范围内出现两个由缺陷引起的中间带(IB)吸收行为,快速热退火处理不能减少或消除薄膜沉积过程中形成的缺陷态;退火处理影响薄膜的光学带隙Eg,预沉积薄膜经600℃退火处理,Eg值增大了0.26eV。Cuprous oxide （Cu2 O） thin films were deposited by radio frequency （RF）magnetron sputte- ring,using a metallic copper in 02 and Ar mixture atmosphere,and the as-deposited thin films were then annealed by a rapid thermal annealing （RTA） in N2 atmosphere. Effects of substrate temperatures and annealing temperatures on growth behavior, crystalline structure, surface morphology and optical proper- ties of as-deposited and annealed Cue O thin films are investigated. The results show that the thin films deposited at substrate temperatures below 300 ~C are amorphous. The RTA process has obvious influ- ence on the crystallinity of the thin films,but the crystalline phase of the thin films has no change after annealing in Ne atmosphere. The thin films have strong absorbance for wavelengths below 650 nm,and the absorption intensity of thin films increases with annealing temperature increasing. The two optical absorption processes for wavelengths below 400 nm are probed, and these behaviors might arise from the inter-band （IB） absorption, resulting from defect states in thin films, which indicates that the RTA of thin films could not decrease or eliminate defect states during thin films deposition. Moreover,the RTA process affects the optical band gap （Eg） of thin films,and Eg of the thin film annealed at 600 ℃ is en- hanced by about 0. 26 eV compared with that of as-deposited thin film.

关 键 词：Cu2O薄膜 衬底温度 快速热退火(RTA) 光学特性 

分 类 号：TB34[一般工业技术—材料科学与工程]