纳米硅结构薄膜光致发光的温度依赖特性

综合考虑纳米硅结构薄膜的特殊性质,如量子限制效应、光学带隙和光跃迁振子强度对纳米硅粒径的依赖特性以及光学带隙和光辐射的温度依赖特性等,给出了一个解析表达式来分析具有一定粒径分布的纳米硅结构薄膜的光致发光(PL)强度分布,其中选取了两种纳米硅的粒径分布,即高斯分布和对数正态分布。结果表明,随着平均粒径和粒径分布偏差的减小,纳米硅薄膜的PL谱峰蓝移。随着环境温度的升高,纳米硅结构薄膜的PL谱峰红移且相对发光强度减弱。纳米硅结构薄膜光辐射拟合的结果与实验数据的比较分析表明,该模型能够很好地解释纳米硅结构薄膜在不同温度下的PL特性。

Temperature-Dependent Photoluminescence of Silicon-Nanostructure Thin Film

Considering the quantum confinement effect in silicon nanoparticles, the effect of the mean silicon nanoparticle size on optical band gap, optical transition oscillator strength, and the temperature dependence of the band gap and optical radiation, a model is introduced to analyze the photoluminescence (PL) of silicon-nanostructure thin film with a certain size distribution of silicon nanoparticles. Where Gaussian function as well as log-normal function is considered for size distribution of silicon nanoparticles. The results show that there will be blue shifts of the PL peak energy decreasing with mean size and size dispersion. As the temperature increases, the PL peak exists red shifts accompanied by decreasing of light intensity. The comparative analysis of the simulation results and experimental data of PL implies shows that our model can well explain the PL in silicon nanostructure thin film in different temperatures.