热丝化学气相沉积技术低温制备多晶硅薄膜的结构与光电特性

以金属W和Ta为热丝，采用热丝化学气相沉积 ，在250℃玻璃衬底上沉积多晶硅薄膜.研究了热丝温度、沉积气压、热丝与衬底间距等沉积参数对硅薄膜结构和光电特性的影响，在优化条件下获得晶态比X_c＞90%，暗电导率σ_d=10^-7—10-6Ω ^-1cm^-1，激活能E_a=0.5eV，光能隙E_opt≤1.3 eV的多晶硅薄膜. 关键词： 多晶硅薄膜 热丝化学气相沉积 光电特性

Structual and optoelectronic properties of polycrystalline silicon thin films p repared by hot-wire chemical vapor deposition at low temperatures

Polycrystalline silicon thin films were prepared by hot-wire chemical vapor deposition (HWCVD) on glass at 250℃，with W or Ta wire as the catalyzers. The structual and optoelectronic properties as functions of the filament temperature, deposition pressure and the filament-substrate distance were studied，and the optimized polycrystalline silicon thin films were obtained with X_c>90% (X_c denotes the crystalline ratio of the film), crystal grain size ab out 30—40nm, R_d≈0.8nm/s, σ_d about 10^-7—10^-6 Ω^-1cm^-1,E_a≈0.5eV and E_opt≤1.3eV.