退火对nc-Si镶嵌复合薄膜结构及发光特性的影响

采用减压化学气相沉积方法，依靠纯N2稀释的SiH4气体的热分解反应，在玻璃表面生长了纳米硅
镶嵌的复合薄膜.实验研究了退火前后薄膜样品的结晶状态和光致发光特性.结果表明，未退火样品的光致
发光特性随沉积温度升高反而减弱.当退火温度＞600℃时，晶化趋势明显；当退火温度＜600℃时，对晶
化的影响不显著，但提高退火温度或延长退火时间可以增加光致发光谱(PL)强度.通过HRTEM分析证实了薄
膜为纳米硅镶嵌复合的特殊结构.并通过Raman、PL、HRTEM的比较分析，认为在退火前后分别有两种不同
的发光机制起主导作用.

Effect of annealing on microstructure and photoluminescence of nano-composite silicon film

A specially designed chemical vapor deposition (CVD) system with SiH_4 as the source gas was constructed to grow nano-composition silicon films on glass substrate. The microstructure and photoluminescence of these films were systematically studied by measurements of micro-Raman, photoluminescence (PL) and high resolution transmission microscope (HRTEM). The results show that the increasing deposition temperature decrease the PL intensity of the as-deposited samples. The annealing temperature below 600 don't strongly affect the crystallization. And increasing the annealing temperature or prolonging the annealing time enhances the PL intensity obviously. HRTEM analysis confirms that the film had a special nano-composite structure. Relevant investigation shows that two luminescence mechanisms can explain the different PL intensity of as-deposited and annealed samples.