纳米晶粒多晶Si薄膜的低压化学气相沉积  

Low Pressure Chemical Vapor Deposition of Nanograin Polysilicon Thin Films

作　　者：彭英才[1] 马蕾[1] 康建波[1] 范志东[1] 简红彬[1] 

机构地区：[1]河北大学电子信息工程学院

出　　处：《人工晶体学报》2006年第3期560-564,共5页Journal of Synthetic Crystals

基　　金：河北省自然科学基金(No.503125);中国科学院半导体研究所半导体材料科学重点实验室开放课题资助

摘　　要：利用低压化学气相沉积(LPCVD)方法,以充Ar的S iH4作为反应气体源,在覆盖有热生长S iO2层的p-(100)S i衬底上制备了具有均匀分布的纳米晶粒多晶S i膜(nc-poly-S i)。采用扫描电子显微镜(SEM)、原子力显微镜(AFM)和拉曼谱等检测手段,测量和分析了沉积膜层的表面形貌、晶粒尺寸与密度分布等结构特征。结果表明,nc-poly-S i膜中S i晶粒的尺寸大小和密度分布强烈依赖于衬底温度、S iH4浓度与反应气压等工艺参数。典型实验条件下生长的S i纳米晶粒形状为半球状,晶粒尺寸约为40nm,密度分布约为4.0×1010cm-2和膜层厚度约为200nm。膜层的沉积机理分析指出,衬底表面上S i原子基团的吸附、迁移、成核与融合等热力学过程支配着nc-poly-S i膜的生长。Uniform nanograin polysilicon films （nc-poly-Si） were fabricated on the thermally grown SiO2 surface by low pressure chemical vapor deposition （LPCVD） of Ar-diluted Sill4 gas. The structural characteristics of the nc-poly-Si films were also analyzed by scanning electronic microscopy （SEM）, atomic force microscopy （AFM） and Raman scattering spectroscopy. The results indicate that the size and density of the Si nanograins in the nc-poly-Si films strongly depend on the technique parameters, such as deposited temperature, SiH4 gas concentrantion and reactive gas pressure. The Si nanograins formed under the typical experimental conditions are hemispherical, and their size is about 40nm and density,4. 0 ×10^10 cm^2, respectively. The deposition mechanism of the films conforms that the absorption, migration, nucleation and mergence of Si atomic radicals on the SiO2 surface dominate the growth process of the nc-poly-Si films.

关 键 词：LPCVD 纳米晶粒 多晶Si膜 结晶成核 晶粒融合 

分 类 号：O484[理学—固体物理]