入射介质对GaN基分布布拉格反射器的反射谱影响  

Influence of different incident medium on reflectance spectra of the GaN-based distributed Bragg reflector

作　　者：郑树文[1] 范广涵[1] 李述体[1] 周天明[1] 

机构地区：[1]华南师范大学光电子材料与技术研究所,广东广州510631

出　　处：《量子电子学报》2007年第4期514-518,共5页Chinese Journal of Quantum Electronics

基　　金：广州科技计划项目(2005Z1-D0071)

摘　　要：利用传输矩阵法对不同入射介质的GaN基分布布拉格反射器(DBR)进行了反射谱的理论分析。计算表明,入射介质的折射率与低周期DBR反射率呈二次函数关系,与高周期DBR反射率近似线性关系。根据这些特点,推导出估算DBR在LED器件中的实际反射率公式。分析了从空气和Al_(0.4)Ga_(0.5)In_(0.1)N入射介质下不同GaN基DBR结构的反射光谱差异。为减弱入射介质对DBR反射谱的影响以及改善材料结构的质量,设计了半混合GaN基DBR结构。分析指出,半混合DBR在材料结构生长和光谱方面比传统DBR更有优势。The reflected spectra of GaN-based DBR at different incident medium are studied theoretically by transfer matrix method. The results show that the reflectivity of DBR depends on the refractive index of the incident medium with quadratic function when the periods of GaN-A1xGa1-xN DBR are under 15 and the reflectivity is about linear ,with the refractive index of the incident medium when the periods are over 15. Based on this relation, a simple formula is deduced in order to estimate the actual spectral reflectivity of DBR in LED. The differences of the reflected spectra of different GaN-based DBR at air and Al0.4Ga0.5In0.1N incident medium are analyzed in detail. A half-hybrid GaN-based DBR structure designed is more predominant than conventional DBR structure designed in reducing the difference of the reflectance spectra of DBR at different incident medium, improving material growth and enhancing light extraction of LED.

关 键 词：光电子学 布拉格反射器 传输矩阵法 GaN基 入射介质 

分 类 号：TN248[电子电信—物理电子学] TN209