摘要
利用Kronig-Penney模型从理论上计算了Si/SiO2和Si/SiNx/SiO2多层膜结构中量子阱的能带结构,进一步分析了各亚层薄膜厚度对能带结构和有效质量的影响.结果发现,适当减少亚层的厚度都能使得纳米Si薄膜的带隙发生明显宽化.在Si/SiO2超晶格中,Si量子阱层带隙能量随着Si层厚度的变化符合EPL(eV)=1.6+0.7/d2关系,与我们的计算结果十分吻合.在Si/SiNx/SiO2超晶格系统中,可以通过控制各亚层厚度,尤其是Si和SiNx层厚度,均能够有效地控制发光.
The band structures of Si/SiO2 and Si/SiNx/SiO2 multilayers were calculated by using Kronig-Penney model. The effect of the sublayer thickness on the band structures and effective mass of electrons and holes was analyzed. It is found that the bandgap of the Si sublayer is obviously widened. For Si/SiO2 system, the variation of the bandgap of the Si sublayer conforms to the empirical formula EpL（eV）=1.6＋0.7/d2, which is in excellent agreement with our calculations. The calculations in Si/SiNx/SiO2 system reveal that the luminescent position can be well controlled by controlling the Si or SiNx sublayer thickness.
基金
教育部留学回国人员科研启动项目(批准号:教外司留[2007]1108)
四川省青年科技基金(编号:08ZQ026-025)资助项目
关键词
K—P模型
超晶格
能带结构
Si层厚度
带隙宽化
量子限制效应
kronig-penney model, superlattices, energy band structure, thickness of Si layer, bandgap widening, quantumconfinement effect
