在加热的BK7基板上，采用电子束蒸发(EB)工艺制备了一系列不同厚度的HfO ₂单层膜，对HfO ₂薄膜生长过程中的折射率非均质性进行了研究。光谱分析表明薄膜非均质性与其厚度息息相关。X射线衍射(XRD)测试表明不同非均质性薄膜对应不同的微观结构；薄膜的微观结构主要由薄膜的生长机制决定。当膜厚较薄时，薄膜不易结晶，呈无定形态，此时薄膜呈正非均质性。如果沉积温度足够高，则薄膜达到一定厚度后开始结晶，此后薄膜折射率就会逐渐下降。随着薄膜继续生长，薄膜晶态结构保持恒定不再变化，非均质性也会因此保持不变达到极值。

To study the evolution of refractive inhomogeneity in hafnia thin films, single layers with different thickness were prepared on BK7 substrates by Electron Beam(EB) evaporation process. The spectral measurements showed that the inhomogeneity of HfO ₂ thin films was significantly affected by the layer thickness. X-ray diffraction(XRD) measurements showed that the crystalline microstructure of HfO ₂ thin films had direct influence on their inhomogeneity and the microstructure was determined by thin film growth mechanism. Due to amophous surface of BK7, thinner films are hard to crystallize and the refractive index of the HfO ₂ thin films are prone to the positive inhomogeneity. If the deposition temperature is high enough, films reaching a certain thickness begin to crystallize, which causes more and bigger voids in the film and results in negative inhomogeneity. When film grows thick engough, the microstructure tends to being stable, and the layer inhomogeneity is independent of thickness and fixed to a certain value.