HfO_2薄膜折射率非均质性生长特性研究  

Study of the evolution of refractive inhomogeneity in HfO_2 thin films

作　　者：鲍刚华[1,2] 程鑫彬[1,2] 焦宏飞[1,2] 刘华松[3] 王占山[1,2] 

机构地区：[1]同济大学先进微结构材料教育部重点实验室,上海200092 [2]同济大学物理科学与工程学院精密光学工程技术研究所,上海200092 [3]天津津航技术物理研究所天津市薄膜光学重点实验室,天津300192

出　　处：《红外与激光工程》2015年第9期2761-2766,共6页Infrared and Laser Engineering

基　　金：国家自然科学基金(61108036;61235011);高等学校博士学科点专项科研基金(20100072120037);中央高校基本科研业务费专项资金

摘　　要：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Hf O2单层膜,对Hf O2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 HfO2 thin films was significantly affected by the layer thickness. X-ray diffraction （XRD） measurements showed that the crystalline microstructure of HfO2 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 HfO2 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.

关 键 词：光学薄膜 电子束蒸发 HFO2薄膜 折射率非均质性 

分 类 号：O436[机械工程—光学工程]