热丝法低温制备多晶硅薄膜微结构的研究

Microstructure of Poly-Si Thin Films Prepared by Hot-filament Chemical Vapor Deposition at Low-temperature

采用热丝化学气相沉积法（HFCVD）在普通玻璃衬底上低温沉积多晶硅薄膜。利用XRD、拉曼光谱和原子力显微镜（AFM）研究了灯丝与衬底间距（5～10mm），灯丝温度（1800～1400℃）和衬底温度（320—205℃）对薄膜晶体取向、晶化率、晶粒尺寸以及形貌的影响规律。结果表明，随着热丝与衬底间距增加，多晶硅薄膜的晶化率和晶粒尺寸明显减小；随热丝温度的降低，薄膜的晶化率都出现了大致相同的规律：先不断增大后突然大幅减小。

Polycrystalline silicon thin films were prepared by hot-filament chemical vapor deposition （HFCVD） on glass at low-temperatures. The preferential growth orientation, the crystalline fraction and the grain sizes of poly-Si films significantly depend on the filament temperature and the distance of substrate to filament. The effects of deposition parameters on the microstructure of films were characterized by X-ray diffraction （ XRD）, Raman spectrum and atomic force microscopy （AFM）. It was found that the crystalline fraction and the grain sizes of poly-Si films distinctly decreased with the increasing distance of substrate to filament. The crystalline fraction of poly-Si films continuously increased to a maximum value and then rapidly reduced with decreasing filament temperature.