退火处理对不同RF功率下制备ZnO薄膜的结晶性能的影响

Influence of annealing on crystallinity of ZnO thin films prepared by radio frequency(RF) magnetron sputtering under different sputtering powers

采用RF磁控溅射法,在不同溅射功率下在玻璃衬底上制备了ZnO薄膜,并对所制备的ZnO薄膜在空气气氛中进行了不同温度(350-600℃)的退火处理。利用X射线衍射仪(XRD)、扫描电子显微镜(SEM)等研究了退火对不同溅射功率条件下制备的ZnO薄膜晶体性能和应力状态的影响。研究表明,在衬底没有预热的情况下,较低功率(190W)下制备的ZnO薄膜,当退火温度为500℃时,能获得单一c轴择优取向和最小半高宽,张应力在350℃退火时最小;较高功率(270W)下,薄膜最佳c轴取向和晶粒度在600℃退火温度获得,张应力最小的退火温度在350-500℃之间。当衬底预热至300℃时,退火处理对两种功率下制备的薄膜的结晶性能和应力的影响基本一致。

Polycrystalline ZnO films were deposited by radio frequency (RF) magnetron sputtering technique on glass substrate under different sputtering powers and the as-deposited films were annealed at various temperatures (350-600°C) in air. The influence of annealing on the crystallinity of the ZnO films was investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results show that the crystallization of the film has been promoted by annealing, but the influence of annealing on the crystallinity of the ZnO films under different sputtering powers is different when the substrate is not preheated. Deposited with lower sputtering power (190W), the crystallization of the ZnO film can be best and tension stress of the film reaches the lowest after annealing at 350°C, however, deposited with higher sputtering power (300W) the film can obtain its best c-axis orientation and crystallization after annealing at 600°C, and the tension stress reaches lowest after annealing in temperature range of 350-500°C. When the substrate is preheated to 300°C, the influence of annealing on crystallization and stress of ZnO films under two sputtering powers is almost same.