O_2/(O_2+Ar)比对磁控溅射La-Sr-Mn-O薄膜沉积速率的影响

Effect of O_2/(O_2+Ar) Ration on Deposition rate of La–Sr–Mn–O Thin Films Prepared by Magnetron Sputtering

采用直流磁控溅射技术,在不同的O2/(O2+Ar)体积比条件下于Si(100)基片上沉积La–Sr–Mn–O薄膜,结合扫描电子显微分析研究了O2/(O2+Ar)比对薄膜沉积速率的影响。结果表明:薄膜厚度均匀,O2/(O2+Ar)比是影响薄膜沉积速率的重要因素。基体温度和溅射气压较高时,薄膜沉积速率随O2/(O2+Ar)比增加呈抛物线规律下降,O2/(O2+Ar)比由4.4%增加到45.6%,沉积速率减小量可达52.8%;基体温度和溅射气压较低时,薄膜沉积速率随O2/(O2+Ar)比增大呈指数规律下降。薄膜沉积速率下降是由于被溅射原子/离子与氧原子/离子的碰撞几率随氧气含量增加而增大,从而降低了被溅射粒子的能量,使到达基片的粒子数减少。

The La-Sr-Mn-O thin films were deposited on Si（100） substrate by DC magnetron sputtering with different O2/（O2＋Ar） ratio. The effect of O2/（O2＋Ar） ratio on the deposition rate of the films was studied using SEM （scanning electron microscopy） analysis. The results showed that the film thickness was homogeneous and the O2/（O2＋Ar） ratio displayed an important effect on deposition rate. The deposition rate of films grown at higher substrate temperature and sputtering pressure decreased in parabolic relation with the increasing of O2/（O2＋Ar） ratio. It decreased 52.8% when O2/（O2＋Ar） ratio increased from 4.4% to 45.6%. The deposition rate of films grown at lower substrate temperature and sputtering pressure decreased in exponential relation with the increase of O2/（O2＋Ar） ratio. The increase of oxygen content increased the collision probability between oxygen atoms/ions and sputtered atoms/ions, which decreased the kinetic energy of sputtered atoms/ions. Then the number of sputtered atoms/ions arriving at substrate decreased, which resulted in the reduction of deposition rate.