采用乙烷气体辉光放电法在单晶Si衬底上制备了名义厚度分别为75,150和250nm的类金刚石碳(DLC)薄膜,除沉积时间外其他工艺参数完全一致。使用可变入射角光谱型椭偏仪(VASE)测量了380～1700nm波段的椭偏谱。该研究发现,对单一DLC样品的椭偏数据进行分析时,一定的范围内,假定不同的薄膜厚度均可以得到非常好的拟合结果。结果表明,采用单样品椭偏法拟合时,厚度与光学常数呈现出强烈的关联性,无法快速获得准确的结果。采用多样品椭偏法,对三个样品建立相同的物理模型,假定他们的光学常数相同,进行数据拟合。分析发现该方法可以快速、简便地获得精确的折射率、消光系数以及厚度值。经过检验,结果具有非常好的唯一性。 The diamond-like carbon (DLC) films with nominal thicknesses of 75, 150 and 250 nm were prepared on a single-crystal Si substrate by the ethane gas glow discharge method. All the other process parameters were identical except for the deposition time. Ellipsometry in the 380-1700 nm band was measured using a variable incident angle spectral ellipsometer (VASE). The study found that within a certain range of analysis of ellipsometric data for a single DLC sample, very good fit results were assumed for different film thicknesses. The results show that the thickness and the optical constants show a strong correlation when the single-sample ellipsometry is fitted, and the accurate results can not be obtained quickly. Using the multiple sample ellipsometry, the same physical model was built for the three samples, assuming that their optical constants were the same for data fitting. The analysis shows that this method can get accurate refractive index, extinction coefficient and thickness value quickly and easily. After testing, the results have very good uniqueness.