【作者】 芦奇力；

【导师】 陈光华；

【作者基本信息】 北京工业大学 ， 材料物理与化学， 2003， 硕士

【摘要】 非晶硅（a-Si）与晶态硅的结构差异，使非晶硅具有特殊的光学、电学性质，并且呈现出了巨大的应用前景。但是由于它含有大量的缺陷态（主要缺陷态是悬挂键），使其在实际应用方面受到了约束。对于氢化非晶硅（a-Si:H），由于氢通过无连接端的硅原子键合来消除缺陷，使得氢化非晶硅的缺陷密度比未氢化的非晶硅大大降低了，从而使氢化非晶硅符合器件级质量材料的要求。a-Si:H薄膜已经广泛应用于太阳能电池，而且作为薄膜场效应管在电子摄像，计算机记忆，平板显示器等领域的应用也有很大进展。但是a-Si:H的沉积速率和品质很大程度上受到制备工艺的影响。为了获得高速沉积下的高品质a-Si:H薄膜，使其能够产业化，微波电子回旋共振化学气相沉积（MWECR CVD）方法在国际上受到了人们广泛的重视。MWECR CVD方法具有电子和离子产生率高等优点，人们期望它能在较高的沉积速率下获得器件级质量的a-Si:H薄膜。因此，我们用MWECR CVD系统在不同的工艺条件下沉积了a-Si:H薄膜。 影响a-Si:H薄膜沉积速率的机制非常复杂，这些机制与制备工艺条件有着密切的联系。我们研究了工作气压、SiH₄气体流量和衬底温度等工艺条件与a-Si:H薄膜沉积速率的关系。同时为了获得高沉积速率、大面积均匀的a-Si:H薄膜，我们改变等离子体的磁场位形为磁镜磁场。研究了磁镜磁场对薄膜沉积速率及均匀性的影响，并且在实验中得到了高沉积速率、大面积均匀的a-Si:H薄膜。 a-Si:H薄膜的光电特性同膜中的氢存在密切关系。Fourier红外透射（FTIR）谱是研究氢化非晶硅（a-Si:H）薄膜中氢含量（C_H）及硅-氢键合模式（Si-H_n）最有效的手段，对于微波等离子体化学气相沉积（MWECR CVD）方法在不同H₂／SiH₄稀释比下制备出的氢化非晶硅薄膜，我们通过红外透射光谱的基线拟合、高斯拟合分析，得出了薄膜中的氢含量，硅氢键合方式及其组分，并分析了这些参数随H₂／SiH₄稀释比变化的规律。更多还原

【Abstract】 The difference between amorphous silicon (a-Si) and crystal silicon(c-Si) on structure, made a-Si has special optical and electronic characteristics. So it had huge prospect of application. But there are a lot of defects (dangling band) in amorphous silicon, therefore its application have been limited. To hydrogenated amorphous silicon (a-Si:H), however, it has much less defects than non-hydrogenated a-Si, for the sake of much hydrogen which eliminate the defects by making a bond with non-connected Si bond. With these virtue, a-Si:H accord with device quality. The films of a-Si:H have widely used in solar cell, film transistor and flat display. But the deposition rate and quality of a-Si:H was primarily affected by preparation methods. Recently, the microwave electron cyclotron resonance (MWECR) CVD method was weightily studied. In view of its virtue of high degree of electron and ion generations, MWECR CVD method is expected to deposit device quality a-Si:H at high deposition rate. Thus, we have prepared a-Si:H films under diverse conditions using MWECR CVD.The mechanism of affecting the deposition rate of a-Si:H, was very perplexing, and had close relation with preparing methods. We studied the relationship of pressure, flux of SiH4 and substrate temperature with deposition rate of a-Si:H films. On the same time, in order to gain high deposition rate and fine uniformity a-Si:H films, we transformed the magnetic configuration to mirror magnetic field by. We studied the effect of mirror magnetic field to deposition rate and homogeneity in large area, moreover, gained large-area homogeneous films at high deposition rate.The photoelectric property of a-Si:H films is closely associated with hydrogen content in films. The Fourier transform infrared (FTIR) spectrum is an effective technology for studying the hydrogen content (CH) and the silicon-hydrogen bonding configuration (Si-Hn) of hudrogenated amorphous silicon (a-Si:H) films. In the paper, CH and Si-Hn of a-Si:H films, fabricated at different ratio of H2/SiH4 by microwaveelectron cyclotron resonance plasma chemical vapor (WMECR CVD) method, have been obtained by analyzing their FTIR spectra that are treated by baseline fitting and Gaussian function fitting. The effects of ratio of H2/SiH4 on CH and Si-Hn are studied.更多还原