氢稀释对纳米晶硅薄膜微结构的影响  

Effect of hydrogen dilution on microstructure of nanocrystalline silicon thin films

作　　者：于威[1] 卢海江[1] 路万兵[1] 孟令海[1] 王新占[1] 韩理[1] 傅广生[1] 

机构地区：[1]河北大学物理科学与技术学院,河北保定071002

出　　处：《功能材料》2011年第3期524-527,共4页Journal of Functional Materials

基　　金：国家自然科学基金资助项目(60878040)

摘　　要：采用电感耦合等离子体化学气相沉积技术制备了氢化纳米硅薄膜,利用Raman散射、X射线衍射、红外吸收等技术对不同氢稀释条件下薄膜的微观结构和键合特性变化进行了研究。结果表明,较高的氢稀释比导致薄膜从非晶硅到纳米晶硅的结构转化,随着氢稀释比的增加,所沉积薄膜的晶化度及纳米晶硅的晶粒尺寸单调增加,纳米硅颗粒呈现在(110)方向的择优生长趋势。键合特性分析显示,随氢稀释比增加,薄膜中整体键合氢含量减小,而SiH2键合比例呈现显著增加趋势,该结果反映了氢原子刻蚀和纳米硅界面面积比的同时增强。光学吸收谱分析表明,通过改变反应气体的氢稀释比,可实现从1.72～1.84eV光学带隙可调的纳米硅薄膜制备。A series of hydrogenated nanosilicon films were prepared by inductively coupled plasmas（ICP） chemical vapor deposition technique from a mixture of SiH4 diluted in H2.A variety of techniques including Raman scattering,X-ray diffraction and infrared absorption were utilized to analyze the microstructure and bonding characteristic of the deposited films at different hydrogen dilution ratio.Results indicate that a rapid structural transformation from a mostly amorphous phase to comprehensive nanocrystal was attained at a relatively high H2 dilution ratio.With increasing hydrogen dilution ratio,the crystalline fraction and grain size monotonically increase,and nanosilicon grains present preferential growth along the（110） direction.The results of FTIR studies show that when increasing hydrogen dilution ratio,the total hydrogen incorporation decreases while the SiH2 bond increases significantly.These indicate that grain-boundary area ratio and atomic-H etching are increased.The analysis of optical absorption spectrum reflects that we have extracted the regulation of optical band gap of nanocrystalline silicon（nc-Si） thin films in the spectral range from 1.72 to 1.84eV by tuning hydrogen dilution ratio.

关 键 词：纳米晶硅薄膜 电感耦合等离子体 晶态比 氢稀释比 

分 类 号：TN304[电子电信—物理电子学]