利用微波电子回旋共振增强磁控反应溅射法在不同基片温度下制备无氢SiNx薄膜.通过傅里叶变换红外光谱、透射电子显微镜、台阶仪、纳米硬度仪等表征技术,研究了基片温度对SiNx薄膜结晶状态、晶粒尺寸、晶体取向等结晶性能以及薄膜的生长速率、硬度等机械性能的影响,并探讨了薄膜结晶性能与机械性能之间的关系.研究结果表明,在基片温度低于300℃时制备的SiNx薄膜以非晶状态存在,硬度值仅为18 GPa左右;基片温度在320—620℃范围内,SiNx薄膜中出现纳米晶粒,且晶粒尺寸随沉积温度的增加而增加,在沉积温度为620℃时达到最大,为20±1.5nm;当沉积温度为700℃时,SiNx薄膜的晶粒尺寸突然减小,但由于此时晶粒密度为最大,因此薄膜硬度达到最大值(36.7 GPa).
Hydrogen-free SiNx films were deposited at substrate temperature ranging from room temperature to 700℃ by microwave electron cyclotron resonance plasma enhanced unbalanced magnetron sputtering system.We have studied the influence of substrate temperature on the structural characteristics of deposited films including growth rate,microstructure,grain size,and hardness by using transmission electron microscopy,Fourier-transform infrared spectroscopy,and nano-indentation.The results indicate that the films deposited at room temperature are amorphous,and α-Si3N4 grains with random epitaxial sizes appear when substrate temperature is higher than 300℃.The α-Si3N4 grain size increases with substrate temperature up to 620℃,and then decreases at 700℃.At 700℃,the grains have uniform epitaxial sizes,and value of the film hardness reaches the maximum(36.7 GPa).