Abstract Achieving epitaxial growth of III-As on r-plane sapphire would potentially allow the integration of both laser and amplifier with corresponding RF electronics. Here we report on the growth of high-quality GaAs on an r-plane sapphire substrate by molecular beam epitaxy. The epitaxial relationship between GaAs and r-plane sapphire is observed and explained. GaAs on r-plane sapphire resulted in (1 1 1) orientation, similar to growth orientation observed on c-plane sapphire. However, in comparison with growth of GaAs growth on a c-plane sapphire substrate, a stronger interaction is observed between GaAs on r-plane sapphire. The effect of growth temperature is also investigated for GaAs growth on r-plane sapphire. It is found that GaAs island size, density, and orientation can be tuned by varying the growth temperature. Finally, a thin AlAs nucleation layer on r-plane sapphire has been introduced to study its effect on the growth of GaAs. The introduction of the AlAs nucleation layer is found to enhance the wetting of GaAs but at the expense of introducing twinning defects.

中文翻译：

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R-平面蓝宝石衬底上的 GaAs 外延生长

摘要 在 r 面蓝宝石上实现 III-As 的外延生长将有可能将激光器和放大器与相应的射频电子器件集成在一起。在这里，我们报告了通过分子束外延在 r 面蓝宝石衬底上生长高质量 GaAs。观察并解释了 GaAs 和 r 面蓝宝石之间的外延关系。r 面蓝宝石上的 GaAs 导致 (1 1 1) 取向，类似于在 c 面蓝宝石上观察到的生长取向。然而，与在 c 面蓝宝石衬底上生长的 GaAs 生长相比，在 r 面蓝宝石上观察到 GaAs 之间更强的相互作用。还研究了生长温度对 r 面蓝宝石上 GaAs 生长的影响。发现可以通过改变生长温度来调整 GaAs 岛的大小、密度和方向。最后，引入了 r 面蓝宝石上的薄 AlAs 成核层来研究其对 GaAs 生长的影响。发现 AlAs 成核层的引入增强了 GaAs 的润湿，但以引入孪晶缺陷为代价。