不同衬底表面上大晶粒多晶Si薄膜的制备  

Fabrication of Large Grain Polycrystalline Silicon Films on Different Substrates

作　　者：马蕾[1] 张雷[1] 王侠[1] 彭英才[1] 

机构地区：[1]河北大学电子信息工程学院,保定071002

出　　处：《人工晶体学报》2008年第6期1505-1509,1488,共6页Journal of Synthetic Crystals

基　　金：河北省自然科学基金项目(E2008000626);河北大学青年基金项目(No.2006Q21)

摘　　要：利用高频感应加热化学气相沉积(HFCVD)工艺,以H2稀释的SiH4作为反应气体源,分别在n-(111)Si衬底上常规热生长的SiO2层、织构的SiO2层和纳米晶粒多晶Si薄膜表面上,制备了具有均匀分布的大晶粒多晶Si膜。采用扫描电子显微镜(SEM)和X射线衍射(XRD)等检测手段,测量和分析了沉积膜层的表面形貌、晶粒尺寸、密度分布与择优取向等结构特征。结果表明,多晶Si膜中Si晶粒的尺寸大小和密度分布不仅与衬底温度、SiH4浓度与反应气压等工艺参数有关,而且强烈依赖于衬底的表面状态。本实验获得的最好的薄膜中,Si晶粒平均尺寸约为2.3μm,密度分布约为3.8×107/cm2。对薄膜的沉积机理分析表明,衬底表面上Si原子基团的吸附、迁移、成核与融合等热力学过程支配着大晶粒多晶Si膜的生长。Uniform large grain polycrystalline silicon films were fabricated on the thermally grown SiO2 surface, textured SiO2 surface and nanograin polycrystalline silicon surface by high frequency induction heating chemical vapor deposition （HFCVD） and use HE-diluted SiH4 as reactive gas. The structural characteristics of the large grain polycrystalline silicon films were also analyzed by scanning electronic microscopy （SEM） and X ray diffraction （XRD）. The results indicate that the size and density of the Si grains in the polycrystalline silicon films not only was influenced by the technique parameters, such as deposited temperature, SiH4 gas concentration and reactive gas pressure, but also strongly depend on the surface condition of substrates. The size and density of Si grains formed under the typical experimental conditions is about 2.3μm confirms that the absorption, surface dominate the growth and 3.8 ×10^7cm^2, respectively. The deposited mechanism of the films migration, nucleation and mergence of Si atomic radicals on the substrate process of the large grain polycrystalline silicon films.

关 键 词：HFCVD 织构表面 大晶粒 多晶si膜 结构表征 

分 类 号：O78[理学—晶体学]