a-Si_3N_4纳米粒子的能级结构研究

A Study on Energy-level Structure of Nanometer Sized a-Si_3N_4 Particles

用激光化学气相沉积法制备出平均粒径为１０ｎｍ的 ａ－Ｓｉ_３Ｎ_４纳米粒子，对不同浓度的 ａ－Ｓｉ_３Ｎ_４纳米粒子溶液进行了紫外吸收及荧光光谱测试，并首次在３．０～４．１ ｅＶ范围发现６个荧光峰．根据吸收及荧光光谱研究其能级结构，描述了ａ－Ｓｉ_３Ｎ_４纳米粒子的物理结构图像，验证了硅悬挂键Ｓｉ~Ｏ在ａ－Ｓｉ_３Ｎ_４纳米粒子光谱性质中的主导作用．

Namometer sized a-Si_3N_4 particles of 10 nm in average diameter were obtained by Laser induced Chemical Vapor Deposition (LICVD). The spectra of UV absorption and fluorescence of a-Si_3N_4 particles in different colloids were measured. Six fluorescent peaks from 3.0 eV to 4.1 eV were found for the first time. According to the absorption and fluorescence spectra of the particles, we studied their energy level structure. We also demonstrated that silicon dangling bond Si^0 plays a dominant role in the spectrum character for nanometer a-Si_3N_4 particles.