Al掺杂量对Cu(In_(1-x)Al_x)S_2薄膜性能的影响

EFFECT OF Al CONTENT ON THE PERFORMANCE OF Cu(In_(1-x)Al_x)S_2 THIN FILMS

使用廉价的溶剂热法制备黄铜矿结构的Cu（In1-xAlx）S2薄膜，研究Al掺杂量对Cu（In1-xAlx）S2薄膜的晶体结构、形貌、粗糙度和光学性能的影响。结果表明：随着Al掺杂量的增加，Cu（In1-xAlx）S2薄膜的X射线衍射峰向高角度偏移，同时晶粒尺寸变小。CuInS2的原位变温XRD结果显示CuInS2在低于873K时可以稳定存在，当温度达到873K时CuInS2则开始分解为In2S3和Cu2S。AFM的测试结果展示薄膜表面的粗糙度随着Al掺杂量的增加而逐步降低。紫外分光光度计的测试结果呈现Cu（In1-xAlx）S2薄膜透过率随着Al含量的增加而逐步增加。Al／（Al＋In）的量在0-0．5变化时，Cu（In1-xAlx）S2薄膜的禁带宽度的相应变化为1．56～2．24eV。

Chalcopyrite compound Cu（In1-xAlx）S22 thin films were prepared by a low-cost and non-vacuum wet chemical process. The effect of aluminum concentrations on the crystal structure, morphology, roughness and optical properties of Cu（In1-xAlx）S2 thin films were investigated. The X-ray diffraction （XRD）showed that the size of crystal grains decreased and the peaks shifted toward high angle side with the increase of Al concentrations. The in-situ XRD results showed that CuInS2 remains stable below the temperature of 873 K and it starts decomposed to In2S3 and Cu2S at temperature above 873 K in vacuum annealing. Scanning electron microscope （SEM）presents th smaller with Al concentrations increasing. AFM data showed that the roughness e size of particles is gradually of thin films decreases with Al become content increasing. The transmission spectrum showed that spectral transmittance decreases with decreasing contents of Al. The band gap of Cu（In1-xAlx）S2 is continuously tuned in a range of 1.56-2.24 eV as Al/（AI＋In） content ratio varied from 0 to 0.5.