Si films have important applications in solar cell industry.Crystallization taking place in Si films has a large impact on their properties and efficiency.Research on the crystallization of films is significant to solar cells.The selective etching model suggests that H atoms will bombard the film growth surface,break the weak chemical bonds,and prompt to form stronger crystal Si-Si bonds.Specific process was simulated by Monte Carlo methods,and the results showed that film phase transition mainly occurred when the growth temperature was above 350K (77℃).If the growth temperature was below 550K,crystallizing occurred only when hydrogen dilution exceeded 90 ％.The simulation results were in accordance with the experimental data when hydrogen dilution was high,but deviated from that when hydrogen dilution was low.The reason was that the intermediate product needed during crystallization was relatively little when hydrogen dilution was low,and other radicals not taken into account in the model may also affect the relative numbers,bringing about some deviations to the simulation.In conclusion,the Si films crystallization model is reasonable to some degree.%硅薄膜在太阳电池中有非常重要的应用,薄膜的晶化对硅薄膜的性质和太阳电池效率都有很大影响,研究薄膜晶化理论具有重要意义.选择刻蚀模型认为H原子会轰击薄膜生长表面,打断吸附较弱的化学键,促使形成强的Si-Si键,使薄膜发生晶化.通过Monte Carlo法对具体的生长晶化过程进行了模拟计算,发现薄膜晶相的转变发生在生长温度350K(77℃)以上,并且在低温(T＜550K)下,晶化的过程主要发生在氢稀释度90％以上.结果与实验数据在高氢稀释下基本吻合,低氢稀释下有偏差.认为低氢稀释下晶化反应所需中间产物产量少,模型中未被考虑的其他基团影响了它们的相对数量,造成模拟结果的偏差.模型对硅薄膜晶化过程的理论解释有一定的合理性.
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