热处理对CuInS_2薄膜导电类型及光学特性的影响  

The effect of heat treatment on the conductive type and optical properties of the CuInS_2 thin films

作　　者：和江变[1,2] 李健[1,2] 董斌华[1] 

机构地区：[1]内蒙古大学物理科学与技术学院,内蒙古呼和浩特010021 [2]内蒙古自治区高等学校半导体光伏技术重点实验室,内蒙古呼和浩特010021

出　　处：《真空》2013年第5期9-13,共5页Vacuum

基　　金：内蒙古自治区自然科学基金项目(2009MS0109);内蒙古自治区高等学校科技项目(NJ10017)

摘　　要：真空蒸发在载玻片上沉积CuInS2薄膜(Cu、In、S原子配比为1:0.1:1.2)。摸索CuInS2薄膜发生导电类型转换最有效的热处理条件,研究不同热处理工艺对CuInS2薄膜的结构、表面形貌、化学成分比和光学性能的影响。实验给出:沉积的薄膜进行360℃热处理30 min后,得到黄铜矿结构的CuInS2薄膜;SEM分析显示薄膜表面呈颗粒状较平整致密性略差,导电类型为N型,薄膜的本征吸收限为1.46eV,直接光学带隙Eg=1.38 eV。对薄膜进行370℃热处理20 min同样可得到N型CuInS2但含有少量的CuS2成分,薄膜表面致密性变好但粗糙度增大,本征吸收限发生红移为1.42 eV,Eg=1.40 eV。370℃,30 min热处理后可得到P型CuInS2薄膜,Eg=1.37 eV。制备的三种CuInS2薄膜的光吸收系数都在104cm-1数量级以上。CuInS2薄膜中In或Cu元素含量大小,对薄膜的导电类型的变化起着决定性的作用,而薄膜中S和In元素的变化直接取决于热处理的条件。The high pure Cu,In,S powder was mixed by the ratio of 1∶0.1∶1.2,followed by vacuum evaporated on the glass slide.The optimum heat-treatment condition for the conductive type conversion of the thin films was studied.The effects of different heat-treatment process on the properties of thin films,including the structure,surface morphology inner chemical composition and optical properties,were also studied.Experimental results show that optimized heat treatment condition is critical for the conductive type conversion of CuInS2 thin films.The CuInS2 thin film prepared with heat-treatment for 30mins at 360℃ presents N-type chalcopyrite structure,and the thin film is fiat slightly with graininess and compactness.The intrinsic absorption edge is 1.46eV,and the direct optical band gap is 1.38eV.The CuInS2 thin film prepared with heattreatment for 20 mins at 370℃ is also N-type chalcopyrite structure,but contains a small amount of CuS2 component,the compactness is better,yet the roughness is increased.The intrinsic absorption edge of the thin film is 1.42eV,showing red shift,and the direct optical band gap is 1.40eV.The CuInS2 thin film prepared with heat-treatment for 30 mins at 370℃ is Ptype chalcopyrite structure,with the direct optical band gap of 1.37 eV.The photoabsorption coefficients of the three kinds of thin films are all over 104 order of magnitudes.The In and Cu contents in the CuInS2 thin films play a decisive role in the conductive thpe conversion,while the S and In contents directly depend on the heat treatment conditions.

关 键 词：真空蒸发 热处理 CuInS2薄膜 导电类型 光学特性 

分 类 号：O484[理学—固体物理]