AlGaN基紫外分布式布拉格反射镜的结构优化

Structure Optimization of AlGaN-Based Ultraviolet Distributed Bragg Reflector

采用传统的相关性分析方法,结合光学传输矩阵理论为基础的商用膜系设计软件,对紫外波段(中心波长314nm)AlGaN基布拉格反射镜的反射光谱进行了一系列模拟,研究了部分结构参数与反射率、中心波长的相关性及相关系数。理论分析结果表明:在保持周期厚度不变的情况下,分层厚度,尤其是AlGaN分层厚度的变化对最终反射率和中心波长的影响最大,且为负相关,并借此优化得到具有较高反射率、较宽探测波段的紫外AlGaN基布拉格反射镜结构参数。相关性分析和优化结果与实际相符,为紫外AlGaN基布拉格反射镜的设计和应用提供了新的思路和研究手段。

Commercial coating design software based on optical transfer matrix theory and traditional method of correlation analysis are used to obtain a series of simulated reflection spectrum of ultraviolet AlGaN-based Bragg reflector （center wavelength of 314 nm）. The correlation between partial structural parameters and reflectivity or center wavelength are studied, as well as the correlation coefficients. The results of correlation analysis show that the thickness of the AlGaN layer is the most impact factor on the reflectivity and the center wavelength, which is a negative correlation. Bases on this conclusion, we obtain an optimal UV AlGaN DBR structure with high reflectivity and wide detection band. Furthermore, the correlation analysis and optimization results match the actual data, which provide a new way and method for the design and application of UV AlGaN DBR.