基于正交试验的Mo薄膜工艺参数优化

Sputtering Parameters Optimization of Mo Thin Films Based on Orthogonal Experiment

Mo薄膜是CIGS薄膜太阳电池背电极的首选材料,对薄膜与基底间的结合力提出很大要求.为提高Mo薄膜与基底结合力,借助L_(9)(3^(3))正交表研究基底温度、溅射气压和溅射功率3种影响因素对Mo薄膜结合力的影响,针对每种因素各选取3个水平值.采用压入法衡量薄膜与基底的结合力,结合力的评价指标为压入引起的裂纹的面积,利用改进版龟裂评级法得出裂纹面积.通过极差分析得到基底温度、溅射气压、溅射功率所对应的R值分别为6.51、18.29、5.96;最优水平组合为A_(1)B_(2)C_(3),此时裂纹面积最小,为2.41μm^(2).结果表明:影响Mo薄膜与基底结合力的因素由主到次为溅射气压、基底温度、溅射功率,综合考虑3种影响因素下Mo薄膜的最优制备工艺参数为溅射功率150 W,溅射气压0.5 Pa,基底温度100℃.

Mo thin films are the preferred material for the back electrode of CIGS solar cells,which puts forward great demands on the adhesion strength between the thin films and the substrate.To improve the adhesion strength,the effect of three factors(depositing temperature,vacuum degree,and sputtering power)on adhesion strength with the help of L_(9)(3^(3))orthogonal table was studied and three levels were selected for each factor.The indentation method was used to measure the adhesion strength between films and substrates.The evaluation criterion of the adhesion strength was the area of indentation-induced cracks,which could be obtained by the improved Uddeholm method.Through range analysis,the R values of depositing temperature,vacuum degree,and sputtering power were 6.51,18.29,and 5.96,respectively.The optimal combination was A_(1)B_(2)C_(3),and the area of cracks was the smallest at that time,which was 2.41.Results show that the effect of vacuum degree on adhesion strength is the largest,then depositing temperature,while the effect of sputtering power is the least.Considering the three factors,the optimal sputtering parameter combination is:power 150 W,pressure 0.5 Pa,and temperature 100℃.