ScAlMgO4 (SAM) has attracted considerable attention as a substrate for growing InGaN template layers owing to its lattice matching with In0.17Ga0.83N. Furthermore, radio‐frequency plasma‐assisted molecular beam epitaxy (RF‐MBE) can be utilized to grow (In)GaN directly on SAM substrates because the growth is conducted at relatively low temperatures without reactive gases. This prevents the diffusion and desorption of the constituent elements of the SAM substrate. In this study, the substrate‐temperature dependence of the direct growth of InGaN on SAM substrates is investigated through RF‐MBE. In droplets are formed below 600 °C, whereas, the In content of the InGaN crystal decreases rapidly, and the surface roughness increases at ≈650 °C. These results are attributed to the acceleration of In desorption at higher temperatures. The improvement in crystal coherency moderates above 600 °C. Therefore, a nearly lattice‐matched In0.18Ga0.82N film is grown at an optimal temperature of 600 °C by adjusting the group‐III metal fluxes. The resulting film is continuous and relatively flat, with no droplets. The dislocation density with screw component is one order of magnitude lower than that of the lattice‐mismatched InGaN. The dislocation density of the InGaN film is comparable to that of a film grown by metal‐organic vapor‐phase epitaxy.

中文翻译：

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使用射频等离子体辅助分子束外延在 ScAlMgO4 衬底上直接生长几乎晶格匹配的 InGaN

镁铝镁合金4（SAM）由于其与 In 的晶格匹配，作为生长 InGaN 模板层的衬底引起了相当大的关注。0.17嘎0.83N. 此外，射频等离子体辅助分子束外延 (RF-MBE) 可用于直接在 SAM 衬底上生长 (In)GaN，因为生长是在相对较低的温度下进行的，没有反应气体。这防止了 SAM 基底的组成元素的扩散和解吸。在本研究中，通过 RF-MBE 研究了 SAM 衬底上直接生长 InGaN 的衬底温度依赖性。 In液滴在600℃以下形成，而InGaN晶体的In含量迅速下降，并且在约650℃时表面粗糙度增加。这些结果归因于较高温度下 In 解吸的加速。晶体相干性在 600 °C 以上时有所改善。因此，几乎晶格匹配的 In0.18嘎0.82通过调整 III 族金属通量，在 600 °C 的最佳温度下生长 N 膜。所得薄膜是连续且相对平坦的，没有液滴。螺旋成分的位错密度比晶格失配的InGaN低一个数量级。 InGaN薄膜的位错密度与金属有机气相外延生长的薄膜相当。