棱镜耦合法的理论改进与实验设计

为了能更精确地测量薄膜厚度及其折射率,介绍了一般棱镜耦合法的测量理论和实验方法,分析了一般的棱镜耦合法测量模型本身存在的理论误差.从测量理论上对棱镜耦合法进行了改进,提出了精确测量模型,减小了上述理论误差,同时给出了薄膜参数的简便计算方法,从理论上分析了薄膜参数计算方法的误差.用传输矩阵的方法进行了模拟论证,设计了实验装置,测量了在玻璃基底上甩胶法得到的Su 8薄膜,测量结果表明,改进的精确测量模型减小了测量误差,提高了测量精度.

Theoretical improvement and experimental design of prism coupler

The measurement principle and experimental design of a normal prism coupler were discussed in order to accurately measure the film thickness and refractive index. The theoretical errors of a normal prism coupler measurement model were investigated, then an accurate model was presented through improving the measurement theory. The convenient method for calculating the thickness and refractive index of a dielectric film was given and its theoretical errors were analyzed. The method was proved by propagating matrix method. With the specially designed experiment equipment, the thickness and refractive index of a Su-8 film on glass substrate by spinning coating were measured using the accurate model. The results showed that the precision measurement model improves the measurement accuracy.