High threading dislocation (TD) density in GaN-based devices is a long unresolved problem because of the large lattice mismatch between GaN and the substrate, which causes a major obstacle for the further improvement of next-generation high-efficiency solid-state lighting and high-power electronics. Here, we report InGaN/GaN LEDs with ultralow TD density and improved efficiency on a sapphire substrate, on which a near strain-free GaN compliant buffer layer was grown by remote plasma atomic layer deposition. This "compliant" buffer layer is capable of relaxing strain due to the absorption of misfit dislocations in a region within ~10 nm from the interface, leading to a high-quality overlying GaN epilayer with an unusual TD density as low as 2.2 × 10(5) cm(-2). In addition, this GaN compliant buffer layer exhibits excellent uniformity up to a 6" wafer, revealing a promising means to realize large-area GaN hetero-epitaxy for efficient LEDs and high-power transistors.

中文翻译：

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接近无应变的GaN兼容缓冲层上GaN外延层中的超低穿线位错密度及其在异质外延LED中的应用。

GaN基器件中的高螺纹位错（TD）密度是一个长期未解决的问题，因为GaN与衬底之间存在较大的晶格失配，这对进一步提高下一代高效固态照明和照明效率构成了主要障碍。大功率电子产品。在这里，我们报告了蓝宝石衬底上具有超低TD密度和更高效率的InGaN / GaN LED，在该衬底上通过远程等离子体原子层沉积生长了几乎无应变的GaN兼容缓冲层。由于吸收了距界面约10 nm以内的失配位错，这种“顺应性”缓冲层能够缓解应变，从而导致高质量的上覆GaN外延层，其TD密度低至2.2×10（ 5）厘米（-2）。此外，