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研究了金属有机物化学气相沉积法制备的不同厚度InN薄膜的位错特性与光电性质.基于马赛克微晶模型,通过X射线衍射非对称面摇摆曲线测量,拟合出样品刃型位错密度分别为4.2×1010cm-2和6.3×1010cm-2,并发现样品的微晶扭转角与位错密度随薄膜厚度增加而减小.通过室温霍尔效应测量得到样品载流子浓度分别为9×1018cm-3和1.2×1018cm-3,采用氮空位作为背景载流子起源的模型解释了随厚度增加载流子浓度的减小与迁移率的增大.光致发光峰随温度的S形非单调变化表明材料中的局域态参与了光学跃迁过程,结合局域态发光和能带收缩效应计算得到样品的局域化能量分别为5.05meV和5.58meV,指出较厚样品中缺陷态的减少是载流子局域化效应削弱的原因.
The dislocation properties and photoelectric properties of InN thin films with different thicknesses prepared by metalorganic chemical vapor deposition (CVD) method were studied.According to the mosaic microcrystal model, the dislocation density of the edge of the sample was fitted by X-ray diffraction asymmetry plane rocking curve 4.2 × 1010cm-2 and 6.3 × 1010cm-2, and found that the crystallite twist angle and dislocation density of the sample decreases with the increase of the film thickness.The carrier concentration of the samples measured by Hall effect at room temperature are 9 × 1018cm- 3 and 1.2 × 1018cm-3, the nitrogen vacancy is used as a model of the background charge carrier to explain the decrease of the carrier concentration and the increase of the mobility with increasing thickness.The photoluminescence peak changes non-monotonously with the S-shape of the temperature It is shown that the localized states in the material are involved in the optical transition process. The calculated localized energies of the samples are 5.05meV and 5.58meV calculated by the luminescence of localized states and the band shrinkage effect, respectively. The reason for the weakening of the localization effect of the flow.