摘要
铜铟镓硒薄膜中4种元素的含量比对薄膜的性能有非常大的影响。采用磁控溅射方法在不同工作气压下制备了铜铟镓硒薄膜,利用激光诱导击穿光谱(LIBS)技术实现了铜铟镓硒薄膜中Ga含量与(In+Ga)含量之比以及Cu含量与(In+Ga)含量之比的定量分析。分析了不同工作气压下制备的铜铟镓硒薄膜中元素谱线的强度,结果表明:IGa/I(In+Ga)与薄膜的禁带宽度是对应的,均随工作气压的增加而先增大后减小,当工作气压为2.0Pa时,获得了最大的薄膜禁带宽度;ICu/I(In+Ga)与能谱仪测得的浓度变化一致。LIBS技术能够实现薄膜中元素含量比例的快速检测,不同元素谱线强度的相对比值能够间接反映薄膜中元素含量的比值,验证了LIBS技术在薄膜分析方面的潜力,为优化磁控溅射制备铜铟镓硒薄膜的工作参数提供了方法和技术支持。
The content ratios of four elements in Cu(In,Ga)Se2(CIGS)thin film have great impact on performance of the thin film.CIGS thin films are deposited by magnetron sputtering at different work pressures,and the laser induced breakdown spectroscopy is used to quantitatively analyze the ratio of Ga content to In and Ga contents,as well as the ratio of Cu content and In and Ga contents.The spectral intensities of elements in CIGS deposited at different working pressures are analyzed,the results show that the intensity ratio of Ga spectral line to In and Ga spectral lines is corresponding to optical band gap,and they increase initially and then reduce with the increase of the work pressure,and the maximum optical band gaps are achieved at the pressure of 2.0Pa,the intensity ratio of Cu spectral line to In and Ga spectral lines is nearly invariable corresponding to the value obtained from energy spectroscopy.The rapid detection of element content proportion in thin film can be realized by LIBS technology,the relative ratios of different intensities of spectral lines can indirectly reflect the element content ratios in thin film,which indicates the potential of LIBS technology in thin film analysis,providing method and technical support for optimizing working parameters in CIGS preparation by magnetron sputtering.
引文
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