Si1－xGex/Si量子阱发光材料的分子束外延生长及其结构研究

采用固源Si分子束外延,在较高的生长温度于Si(100)衬底上制备出Si1－xGex/Si量子阱发光材料。发光样品的质量和特性通过卢瑟福背散射、X射线双晶衍射及光致发光评估。背散射实验中观察到应变超晶格的反常沟道效应;X射线分析表明材料的生长是共度的、无应力释放的,结晶完整性好。低温光致发光主要是外延合金量子阱中带边激子的无声发射和横光学声子参与的激子复合。并讨论了生长温度对量于阱发光的影响。

MOLECULAR BEAM EPITAXY GROWTH AND CHARACTERIZATION OF LUMINESCENT Si1-xGex/Si QUANTUM STRUCTURES

Band edge luminescence with no deep level emissions is reported for Si1－xGex/Si quantum well structures grown at high substrate temperatures by solid source St mole cular beam epitaxy, no-phonon transitions and transverse optical phonon replicas were clearly identified. Systematic studies based on Rutherford ion backscattering and X-ray diffraction were performed.Backscattering and channeling anomalous spectra was observed due to the strain of superlattice.Photoluminescence(PL)and X-ray rocking curve analysis of the sample indicated that a good crystalline quality and commensurate growth is essential to radiative recombination.The dependence of PL on the growth temperature were discussed.