CdSe x S 1-x 电子学结构及光学性质的第一性原理研究 First-principles Investigation on Electronic Structure and Optical Properties of CdSe x S 1-x 何旭 HE Xu 2 first-author 武莉莉 WU Li-li 1 李春秀 LI Chun-xiu 3 郝霞 HAO Xia 1 都政 DU Zheng 4 四川大学 材料科学与工程学院,四川 成都,610101 四川大学 材料科学与工程学院,四川 成都,610101 College of Materials Science and Engineering, Sichuan University College of Materials Science and Engineering, Sichuan University 成都纺织高等专科学校,四川 成都,611731 成都纺织高等专科学校,四川 成都,611731 Chengdu Textile College Chengdu Textile College 宜春学院,江西 宜春,336000 宜春学院,江西 宜春,336000 Yichun University Yichun University 国家超级计算深圳中心,广东 深圳,518055 国家超级计算深圳中心,广东 深圳,518055 National Supercomputing Center in Shenzhen National Supercomputing Center in Shenzhen CdSe是Ⅱ-Ⅵ族中重要的半导体材料，一定条件下可与CdS形成无限固溶体CdSe x S 1-x （0 x 1）。CdSe x S 1-x 在薄膜太阳电池及光电器件等领域具有重要的应用，对CdSe x S 1-x 的电子学结构和光学性质进行研究有助于进一步提高其在光电器件等方面的应用。基于第一性原理，采用平面波超软赝势方法，计算了CdSe x S 1-x 的电子学结构及光学性质，并将计算结果与实验进行了对比。结果表明，CdSe x S 1-x 的晶格常数随着Se组分的增加呈线性增大趋势，态密度向低能级方向移动，禁带宽度减小，光吸收边发生一定程度的蓝移。当Se含量为0.5时，CdSe x S 1-x 的光折射、反射和能量损失最大。除了Se和S的比例为1:1时CdSe x S 1-x 所属晶系为三斜晶系，其他比例下均为立方晶系。理论计算结果与实验符合。 Cadmium selenide(CdSe) is a classic Ⅱ-Ⅵ semiconductor material. Most often, CdSe with CdS can form ternary alloys CdSe x S 1-x (0 x 1). CdSe x S 1-x has a large application in transparency electrode of CdTe thin-film solar cells and optoelectronic device. It is helpful to improve CdSe x S 1-x application value in photoelectric devices studying of its photoelectric properties. This paper calculates and analyzes the electronic structure and optical properties of CdSe x S 1-x ternary alloys with plane pseudo-potential mathod based on first-principles calculations. The calculated results are compared with the experimental results. The calculation results show that the lattice constant of CdSe x S 1-x ternary alloy crystal forming after Se substitutes S partly or wholly presents a tread of linear increase with the increase of Se content. Except Se:S=1:1 the crystal system of CdSe x S 1-x alloy with other ration does not change, forbidden gap decreases gradually and the peak value of state density gradually shifts towards the direction of high energy with the increase of Se content. In addition, the absorption edge exhibits a blue shift with Se concentration increasing. At the same time, reflectivity, loss-function and refractive index show their peak values when Se concentration x reaches 0.5. The calculation results are in good agreement with the experiment results. CdSexS1-x 第一性原理 电子结构 光学性质 CdSexS1-x first-principles electronic structure optical properties HUSAIN M,SINGH B P,KUMAR S,et al.. Optical,electrical and structural investigations on Cd1-xZnxSe sintered films for photovoltaic applications[J]. Sol. Energy Mater. Sol. Cells, 2003,76(3):399-415. FEREKIDES C S,BALASUBRAMANIAN U,MAMAZZA R,et al.. CdTe thin film solar cells:device and technology issues[J]. Sol. Energy, 2004,77(6):823-830. LI C X,WANG F G,CHEN Y L,et al.. Characterization of sputtered CdSe thin films as the window layer for CdTe solar cells[J]. Mater. Sci. Semicond. Process., 2018,83:89-95. PAUDEL N R,GRICE C R,XIAO C X,et al.. The effects of high temperature processing on the structural and optical properties of oxygenated CdS window layers in CdTe solar cells[J]. J. Appl. Phys., 2014,116:044506. PAUDEL N R,XIAO C X,YAN Y F. Close-space sublimation grown CdS window layers for CdS/CdTe thin-film solar cells[J]. J. Mater. Sci.:Mater. Electron., 2014,25(4):1991-1998. DUFFY N W,PETER L M,WANG R L. Characterisation of CdS/CdTe heterojunctions by photocurrent spectroscopy and electrolyte electroreflectance/absorbance spectroscopy (EEA/EER)[J]. J. Electroanal. Chem., 2002,532(1-2):207-214. PAUDEL N R,YAN Y F. Enhancing the photo-currents of CdTe thin-film solar cells in both short and long wavelength regions[J]. Appl. Phys. Lett., 2014,105(18):183510. 杨峻宏,张高峰,高俊芳,等. CdSe:Nd纳米晶及CdSe:Nd@SiO2核壳结构的合成及发光性能[J]. 发光学报, 2018,39(9):1260-1267. YANG J H,ZHANG G F,GAO J F,et al.. Synthesis and fluorescence properties of CdSe:Nd and CdSe:Nd@SiO2 core-shell structures[J]. Chin. J. Lumin., 2018,39(9):1260-1267. (in Chinese) 王亚超,王梅,苏希玉,等. Mg掺杂CdSe电子结构和光学性质的第一性原理[J]. 发光学报, 2010,31(6):842-847. WANG Y C,WANG M,SU X Y,et al.. First-principles on the electron structure and optical properties of the Mg-doped CdSe system[J]. Chin. J. Lumin., 2010,31(6):842-847. (in Chinese) 吴永刚,李世雄,郝进欣,等. 外电场下CdSe的基态性质和光谱特性研究[J]. 物理学报, 2015,64(15):153102-1-7. WU Y G,LI S X,HAO J X,et al.. Properties of ground state and spectrum of CdSe in different external electric fields[J]. Acta Phys. Sinica, 2015,64(15):153102-1-7. (in Chinese) 张淑华,柳福提,程晓洪. CdS电子结构与光学性质的第一性原理计算[J]. 宜宾学院学报, 2011,11(12):77-80. ZHANG S H,LIU F T,CHENG X H. First-principles calculations of electronic structure and optical properties of CdS[J]. J. Yibin Univ., 2011,11(12):77-80. (in Chinese) 何旭,武莉莉,任胜强,等. Zn1-xMgxO电子结构及光学性质的第一性原理GGA+U方法研究[J]. 发光学报, 2018,39(6):795-801. HE X,WU L L,REN S Q,et al.. First-principles GGA+U investigation on the electronic structure and optical properties of Zn1-xMgxO[J]. Chin. J. Lumin., 2018,39(6):795-801. (in Chinese) 何旭,任胜强,李春秀,等. Zn1-xMgxO能带结构及作为窗口层的CdTe薄膜太阳电池的SCAPS仿真应用[J]. 无机材料学报, 2018,33(6):635-640. HE X,REN S Q,LI C X,et al.. Zn1-xMgxO:band structure and simulation as window layer for CdTe solar cell by SCAPS software[J]. J. Inorg. Mater., 2018,33(6):635-640. (in Chinese) FARROW R F C. MBE growth of Ⅱ-Ⅳ and Ⅳ-Ⅵ compounds and alloys[M]. CHANG L L,PLOOG K. Molecular Beam Epitaxy and Heterostructures. Dordrecht:Springer, 1985. ISLAM R,BANERJEE H D,RAO D R. Structural and optical properties of CdSexTe1-x thin films grown by electron beam evaporation[J]. Thin Solid Films, 1995,266(2):215-218. POLLEHN H K. Performance and reliability of third-generation image intensifies[J]. Adv. Electron. Electron Phys.,1985,64:61-69. WANG W,BANERJEE S,JIA S G,et al.. Ligand control of growth,morphology,and capping structure of colloidal CdSe nanorods[J]. Chem. Mater., 2007,19(10):2573-2580. WU Y L,CHEN G D,ZHU Y Z,et al.. LDA+U/GGA+U calculations of structural and electronic properties of CdTe:dependence on the effective U parameter[J]. Comput. Mater. Sci., 2015,98:18-23. ARUSHANOV E K. Ⅱ3Ⅴ2 compounds and alloys[J]. Prog. Cryst. Growth Charact. Mater., 1992,25(3):131-201. DELIGOZ E,COLAKOGLU K,CIFTCI Y. Elastic,electronic,and lattice dynamical properties of CdS,CdSe,and CdTe[J]. Phys. B:Condens. Matter, 2006,373(1):124-130. 10.3788/fgxb20204102.0188 0477.5;0472+.3 国家自然科学基金（61704115）;国家重点研发项目：牛顿基金中英研究创新（2016YFE0124500）资助项目 Supported by National Natural Science Foundation of China(61704115);National Key Research and Development Program of China:Newton Fund-China-UK Research and Innovations Bridges(2016YFE0124500) 2019-09-03 2019-09-19 2019-09-24 2020-02-05 2020-08-11 2 41