低能Ar^+、Xe^+轰击SiO_2的溅射模型

Sputtering model of SiO_2 for low energy Ar^+ and Xe^+ bombardment

为了得到在低能条件下更为精确的Ar^+和Xe^+轰击SiO_2的溅射模型,对已有化合物溅射模型进行调研分析,总结了3种溅射模型,分别为Pencil模型、Bach模型和Seah模型,并对其不足之处加以分析。在Seah模型基础上,对溅射阈值采用新的计算方法,并利用等效原子法改进溅射参数和表面键能的计算方法,形成改进后的新模型。结合已有的关于Ar^+和Xe^+法向轰击SiO_2的实验数据,对4种模型的计算结果进行对比分析。对于Ar^+和Xe^+法向轰击SiO_2,改进后的溅射模型的均方根误差最小,拟合优度最高,均优于其他3种模型。说明在低能状态下,采用改进后的模型可以更为精确地计算Ar^+和Xe^+轰击SiO_2的溅射率。

In order to obtain the more accurate sputtering model of SiO2 for bombardment with low energy Ar ＋ and Xe ＋,three existing models,Pencil model,Bach model and Seah model,were investigated and the deficiencies were analyzed.On the basis of Seah model,the sputtering parameters and surface binding energy were calculated by equivalent atomic method.Meanwhile,a new calculation method of sputtering threshold was applied to form a new advanced model.Combined with the experimental data of SiO2 for bombardment at normal incidence with Ar ＋ and Xe t,the calculation results of the four models were contrastively analyzed.The results show that,for both Ar ＋ and Xe＋ bombardment,the root mean square error of the new advanced model is the smallest and the goodness of fit is the largest,which means the new advanced model is better than other three models.Under the low energy condition,the new advanced model can calculate the sputtering yield of SiO2 bombarded by Ar＋ and Xe ＋ more accurately.