氢化非晶硅 (a-SiH) 薄膜在微电子和光电子工业中有着重要的应用，而椭偏分析技术是一种重要的薄膜表征手段。利用椭偏测量技术并采用Tauc-Lorentz(TL)模型和Forouhi-Bloomer(FB)模型，从不同角度对比研究了a-SiH薄膜的结构和光学特性。分析结果表明，用两种不同模型得到的a-SiH薄膜厚度、粗糙层厚度以及光学常数并不一致，由TL模型得到的薄膜厚度更接近扫描电镜 (SEM) 测量的结果，粗糙层厚度更接近原子力显微镜(AFM)测量结果对应的经验值。结合已发表的文献，分析发现膜厚差异主要来自于模型对薄膜光学参数的不同描述，而光学参数的差异是由于模型推导过程中的不同假设和数学处理产生的。

Hydrogenated amorphous silicon (a-SiH) thin film is a technologically important material in microelectronic and optoelectronic industry, and ellipsometry is one of the important thin film characterization tools. The effects of different optical models including Tauc-Lorentz (TL) model and Forouhi-Bloomer (FB) model on the structural and optical results of a-SiH thin film in ellipsometry analysis are investigated. It is indicated that the measured thin film thickness, roughness and optical constants using different models are inconsistent. The thin film thickness from TL model is closer to the one from scanning electron microscopy (SEM) and the roughness is more comparable to the empirical value corresponding to atomic force microscopy (AFM) result. Combining the published references, it′s found that the varied thin film thickness and roughness are due to the different optical descriptions. Meanwhile, under the condition of different mathematical processing and assumption, the difference between optical constants from FB model and TL model appears.