PECVD方法制备SnO_2气敏薄膜的电子显微镜研究

Electron Microscope Investigqtion of SnO_2 Gas Sensing Films Prepared by PECVD

通过ＳＥＭ、ＴＥＭ研究了ＰＥＣＶＤ方法制备的ＳｎＯ＿２薄膜的显微结构，讨论了沉积速率与颗粒大小的关系；在Ｓｉ、陶瓷和ＫＢｒ３种不同衬底上沉积的ＳｎＯ＿２薄膜的差异以及退火对ＳｎＯ＿２膜结晶状态的影响。结果表明，ＰＥＣＶＤ方法制备的ＳｎＯ＿２薄膜是非晶态，具有柱状结构。退火使非晶ＳｎＯ＿２膜向着多晶方向转化，演化过程为：非晶大颗粒→超微粒多晶→晶粒长大。

The microstructure of SnO_2 films prepared by plasma enhanced Chemical vapour deposition(PECVD)was studied by SEM and TEM.IT isfound that grain size of the SnO_2 films is obviously influenced by the rate of deposition,the annealing processes and substrates,on which thefilms are grown.The results show that the unan-nealed SnO_2 films,predpared by PECVD,are amorphous with a columnar strLicture and the thermalannealing samples are polycrystalline,During thetransform process from the arnorphous state to thepolycrystal grain size of the films decreses clearly,when the temperature high enough and the polycrystal grain size begins to increase.