PECVD法生长的nc－Si：H膜电导率的研究

Study on Conductivities of nc-Si:H Films

使用ＰＥＣＶＤ方法生长了ｎｃ－Ｓｉ：Ｈ膜，Ｘ射线衍射、Ｒａｍａｎ光谱和电镜观测表明样品具备了纳米结构特征。测量了样品在７７Ｋ～４００Ｋ温度范围的电导率，并使用二相随机分布有效介质理论，计算了ｎｃ－Ｓｉ：Ｈ膜中晶粒部分和晶界部分的电导率。对计算结果进行了理论分析，初步探讨了ｎｃ－Ｓｉ结构对其导电性能的影响，提出ｎｃ－Ｓｉ：Ｈ的高电导率来源于膜中纳米晶粒的小尺寸效应。

Using PECVD method,we fabricatednanometer crystalline Si:H(nc-Si:H)films.X-raydiffraction,Raman spectroscopy and electronmicroscopy have been used to detect the structureparameters. Conductivities of the samples atdifferent temperatures from 77K to 400K have beenmeasured. Based on experimental data,we usedeffective-medium theory to calculate theconductivities of nano-crystalline and interface innc-Si:H films. According to calculation results,wesuggest that the high conductivity of nc-Si:H comefrom the crystallite in nc-Si:H films,and this maybe a kind of small size effect.