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对采用金属有机化学气相淀积 (MOCVD)技术生长的GaN1-xPx 三元合金进行了低温光致发光 (PL)和X射线衍射 (XRD)测试分析 .与来自GaN层的带边发射相比 ,P的摩尔分数比为 0 .0 3,0 .11和 0 .15的GaN1-xPx 的光致发光峰分别呈现出了 73meV ,78meV和 10 0meV的红移 ,文中将这种红移归因于GaN1-xPx 合金具有大的带隙能量弯曲系数。X射线衍射结果表明GaN1-xPx 三元合金仍为六方结构晶体 ,且随着P组份比的增加 ,GaN1-xPx合金的 (0 0 0 2 )衍射峰逐渐向小角度方向移动 ,即晶格常量变大 ,同时 ,(0 0 0 2 )衍射峰谱线不断宽化 ,说明由于替位式P原子的不规则分布以及部分间隙P原子的影响造成了GaN1-xPx 样品的晶格畸变。在GaN1-xPx 的光致发光谱及X射线衍射谱中均未观测到相应的有关GaP的峰 ,表明所生长的高P含量的GaN1-xPx 三元合金没有产生明显的相分离。
Low temperature photoluminescence (PL) and X-ray diffraction (XRD) analysis of GaN1-xPx ternary alloys grown by metal organic chemical vapor deposition (MOCVD) The photoluminescence peaks of GaN1-xPx with mole fractions of 0.3, 0.011, and 0.15 of P show red shifts of 73meV, 78meV and 100meV, respectively. The red shift is attributed to GaN1-xPx alloy has a large bandgap energy bending coefficient. The X-ray diffraction results show that the GaN1-xPx ternary alloy is still hexagonal crystal structure. With the increase of the P-component ratio, the (0 0 0 2) diffraction peak of GaN1-xPx alloy gradually moves toward the small angle, At the same time, the (0 0 0 2) broadening of the diffraction peak broadens, indicating that the lattice distortion of the GaN1-xPx samples is caused by the irregular distribution of the substitutional P atoms and the influence of the P atoms in the partial gaps. No corresponding peaks of GaP were observed in the photoluminescence spectrum and the X-ray diffraction spectrum of GaN1-xPx, indicating that no significant phase separation was observed in the grown high-P content GaN1-xPx ternary alloy.