摘要
用分子束外延方法在 Ga As(10 0 )衬底上生长了高质量的 Zn Se/ Zn Sx Se1 - x(x=0 .12 )超晶格结构 ,通过 X射线衍射谱和光致发光谱 ,对其结构特性和光学特性进行了研究 .结果表明 :在 4 .4 K温度下 ,超晶格样品显示较强的蓝光发射 ,主发光峰对应于阱层 Zn Se的基态电子到重空穴基态的自由激子跃迁 ,而且其峰位相对于 Zn Se薄膜的自由激子峰有明显蓝移 .从理论上分析计算了由应变和量子限制效应引起的自由激子峰位移动 。
ZnSe/ZnS x Se 1-x strained layer supplattics with ZnS 0.06 Se 0.94 buffers are grown on GaAs(100) substrates by molecular beam epitaxy and characterized by X ray diffraction and low temperature photoluminescence.The main emission peaks in photoluminescence spectra can be attributed to the free exiton between the lowest electron subband and ground heavy hole subband of ZnSe wells.A blue shift of the excitonic peak is observed.The energy shift due to the strain and quantum confinement are theoretical calculated,showing good agreement with the experimental results.
