论文部分内容阅读
本文给出氦、氩离子法向轰击多晶元素靶时,原子溅射率Y_o随离子能量E变化的经验公式.采用下面二个步骤,可以导出这个公式.首先,把Sigmund 溅射率公式(1)中的表面升华能U_s改为离靶组合的溅射阈能E_(th). 其次,再把上式乘以Matsunami提出的低能修正因子g(E).另外,我们还导出了适用于轻、重离子的溅射阈能经验公式E_(th)=U_s·exp(r)/r.其中:r=4M/(1+M)~2,M=M_2/M_1是靶原子的相对原子量.计算结果表明:对于低能离子(E≤1keV)而言,由经验公式算出的溅射率Y_o与实验值Y之间的相对误差不超过20％.但是,低能下的Sigmund理论溅射率Y_s约为实验值的二至二十五倍.由此可知:经验溅射率公式(30)基本上是成功的.
In this paper, empirical formulas of atomic sputtering rate Y_o with ion energy E are obtained when the helium and argon ions bombard polycrystalline target in a normal direction. This formula can be derived by the following two steps: First, the Sigmund sputtering rate formula 1), the surface sublimation energy U_s is changed to the sputter threshold E_ (th) from the target, and second, the above equation is multiplied by the low energy correction factor g (E) proposed by Matsunami. In addition, The sputtering threshold of light and heavy ions can be obtained by the empirical formula E th th = U_s · exp r / r, where: r = 4M / (1 + M) ~ 2, M = M_2 / M_1 is the relative atomic weight of the target atom The calculated results show that the relative error between sputtering rate Y_o calculated by the empirical formula and experimental value Y does not exceed 20% for low energy ions (E≤1 keV). However, Sigmund’s theoretical sputtering rate Y_s About two to twenty-five times the experimental value.Thus we can see: empirical sputtering rate formula (30) is basically successful.