Cu(In,Ga)Se_2薄膜组成表面分析准确测量国际关键比对

International Key Comparison: Surface Analysis Measurement of Composition for Cu(In,Ga) Se_2 Films

中国计量科学研究院参加了国际关键比对K129,采用X射线光电子能谱仪(XPS)建立了测量薄膜太阳能电池材料铜铟镓硒(CIGS)薄膜组成和深度成分分布的有效方法。采用合适的条件,对CIGS薄膜进行深度剖析,提出并完善了一套XPS深度剖析数据处理方法(全计数法和相对灵敏度因子法),对薄膜组成进行了准确测量。结果表明,该方法的测量重复性良好,5次测量的相对标准偏差(RSD)均小于2%,测量扩展不确定度优于4%,与其他国家计量院的结果取得等效一致。对比研究了不同灵敏度因子来源(由参考样品获得、仪器数据库的3种来源)对CIGS薄膜组成测量结果的影响,结果表明,仪器厂商数据库自修正的灵敏度因子最接近于参考样品,可较好地对CIGS薄膜进行原子含量测量。该方法可推广用于表面分析设备深度剖析薄膜样品时定量计算薄膜成分,提高测量薄膜成分的准确度,为薄膜太阳能电池材料研发和产业化提供参考依据。

The method for quantitative analysis and depth profile analysis of Cu（ In,Ga） Se_2（ CIGS） solar cell films was established using X-ray photoelectron spectroscopy（ XPS） based on international key comparison K129 participated by National Institute of Metrology（ NIM）. The depth sputtering and spectrum acquisition were carried out by using suitable conditions which were obtained through pre-research. The data analysis processes included determination of signal intensity using total number method,determination of relative sensitivity factor,atomic fraction and uncertainty. By using the data processing,a reliable and effective film composition could be obtained. The results indicated this method had a good repeatability with RSD less than 2% in 5 measurements. The atomic fractions of Cu,In,Ga and Se were measured accurately with expand uncertainties less than 4%,which was consistent with those obtained by other national metrology lab. In addition,the analytical result calculated from 4 different sensitivity factors which were obtained from reference sample and instrumental database were compared. The results showed that the values of sensitivity factors from instrumental database modified by the manufacturer were closer to the values obtained from the reference sample,thus the sensitivity factors from instrumental database modified by the manufacturer could be used for the quantitative analysis of atomic composition of alloy films with XPS. The method could be used for the composition measurement of a lot of films with accurate improvement with surface analytical techniques.