采用高温直接溅射Cu-In-Ga-Se四元合金靶材工艺制备光吸收层,通过对预溅射层温度和厚度的调控,研究铜铟镓硒（CIGS）预溅射层对直接溅射法制备CIGS薄膜的（220）择优取向调控机理。结果表明,预溅射层沉积温度逐渐降低时,CIGS薄膜X射线衍射（XRD）I（220）/I（112）比值从0.43增大到1.05,晶粒尺寸逐渐变大且均匀。预溅射层厚度从0增加到120 nm时,I（220）/I（112）比值从0.48增大到1.12。在溅射温度为室温,预溅射层厚度为80 nm时,最终获得单点10.94%的器件效率。分析预溅射层表面AFM和XPS以及器件HRETM,发现低温预溅射层引入能够显著降低衬底表面电位,电压的振幅只有25 mV,较低的表面电位促进了高温沉积CIGS（220）择优取向,同时（220）择优取向促进了化学水浴工艺时Cd离子的掺杂,最终提升了CIGS器件效率。
Abstract
The （220） preferential-oriented CIGS film has a smooth grain surface and can promote the diffusion of Cd or Zn cations, giving CIGS devices better diode characteristics. This thesis uses a high-temperature direct sputtering CIGS quaternary alloy target process to prepare the CIGS absorption layer, by controlling the temperature and thickness of the CIGS pre-sputtering layer, the （220） preferential orientation control mechanism of the CIGS pre-sputtering layer on CIGS thin films prepared by direct sputtering was studied. The results show that when the deposition temperature of the pre-sputtering layer gradually decreases, the X-ray diffraction （XRD） I（220）/I（112） ratio of the CIGS film increases from 0.43 to 1.05, and the grain size gradually becomes larger and more uniform. When the thickness of the pre-sputtering layer increases from 0 nm to 120 nm, the I（220）/I（112） ratio increases from 0.48 to 1.12. When the sputtering temperature was room temperature and the pre-sputtering layer thickness was 80 nm, a single-point device efficiency of 10.94% was finally obtained. Through AFM and XPS testing of the sample surface, we found that the low-temperature pre-sputtering layer can significantly reduce the substrate surface potential, and the amplitude of the voltage is only 25 mV. The lower surface potential promotes the preferential orientation of CIGS （220） deposited at high temperatures while increasing alkali metal doping, ultimately improving CIGS devices'efficiency.
关键词
铜铟镓硒 /
四元靶材 /
磁控溅射 /
择优取向 /
表面电位
Key words
CIGS /
quaternary /
sputtering /
preferred orientation /
surface potential
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基金
国家自然科学基金（62204074）; 河北省自然科学基金（F2022201061）; 河北大学高层次人才科研启动项目（521100221085）
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