Abstract Recently, we developed a Na-flux point seed (PS) technique and fabricated a GaN crystal with an extremely low threading dislocation density (TDD). However, the crystal grown by this technique is mainly composed of the { 10 1 ¯ 1 }-plane, which easily incorporates oxygen impurities. Generally, in the Na-flux method oxygen atoms are easily incorporated at the nitrogen site because the growth is carried out in a nitrogen-poor condition. Therefore, we attempted to fabricate GaN crystals with low oxygen concentration in the flux with a high nitrogen concentration, which was achieved by adding Li into the flux. As a result, the grown GaN crystal exhibited high transparency and the oxygen concentration was the lowest value yet reported for the { 10 1 ¯ 1 }-plane.

中文翻译：

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加锂 Na-Flux 法生长高透明 GaN 单晶

摘要 最近，我们开发了一种 Na-flux point Seed (PS) 技术，并制造了具有极低穿透位错密度 (TDD) 的 GaN 晶体。然而，通过这种技术生长的晶体主要由{ 10 1 ¯ 1 } 面组成，它很容易掺入氧杂质。通常，在 Na-flux 方法中，氧原子很容易在氮位置结合，因为生长是在贫氮条件下进行的。因此，我们尝试在助焊剂中制造低氧浓度和高氮浓度的 GaN 晶体，这是通过在助焊剂中添加锂来实现的。结果，生长的 GaN 晶体表现出高透明度，氧浓度是 {10 1 ¯ 1 } 面的最低值。