Abstract Embedded growth of an n-GaN cap layer on multi-quantum shells (MQSs) and nanowires through a tunnel junction (TJ) was investigated for the improvement of current injection to the m-plane of the MQSs. Different growth conditions for an n-GaN cap layer were systematically studied to suppress Mg diffusion and void formation, which are serious problems in this structure. At a high temperature of 900 °C and above, the growth rate on a semi-polar r-plane decreased, and large voids were formed at the bottom part of the nanowires owing to the diffusion of Ga atoms from the r-plane to the m-plane. When the growth temperature decreased to 800 °C, the growth rate on both the m-plane and the r-plane increased, and the size of voids decreased. Simultaneously, Mg diffusion also disappeared because of the low growth temperature of 800 °C. It was found that the growth with an extremely low V/III ratio of 20 at low temperatures increases the lateral growth rate on the m-plane, and void formation is fully suppressed when the MQS height is 700 nm or less.

中文翻译：

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GaInN/GaN 多量子壳 LED 上 n-GaN 帽层的 MOVPE 生长

摘要 研究了通过隧道结 (TJ) 在多量子壳 (MQS) 和纳米线上嵌入 n-GaN 帽层，以改善对 MQS 的 m 平面的电流注入。系统地研究了 n-GaN 盖层的不同生长条件，以抑制 Mg 扩散和空隙形成，这是该结构中的严重问题。在 900 °C 及以上的高温下，半极性 r 面的生长速度下降，由于 Ga 原子从 r 面扩散到纳米线的底部，在纳米线底部形成大的空隙。 m-平面。当生长温度降至 800 °C 时，m 面和 r 面的生长速率均增加，空隙尺寸减小。同时，由于 800 °C 的低生长温度，Mg 扩散也消失了。