Abstract The homoepitaxial growth of N-polar GaN was investigated by ammonia molecular beam epitaxy. Systematic growth studies varying the V/III flux ratio and the growth temperature indicated that the strongest factor in realizing morphologically smooth films was the growth temperature; N-face films needed to be grown approximately 100 °C or greater than Ga-face films provided the same metal flux. Smooth N-face films could also be grown at temperatures only 50 °C greater than Ga-face films, albeit under reduced metal flux. Too high a growth temperature and too low a metal flux resulted in dislocation mediated pitting of the surface. The unintentional impurity incorporation of such films was also studied by secondary mass ion spectroscopy and most importantly revealed an oxygen content in the mid 10 17 to the mid 10 18 cm −3 range. Hall measurements confirmed that this oxygen impurity resulted in n-type films, with carrier concentrations and mobilities comparable to those of intentionally silicon doped GaN.

中文翻译：

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通过氨分子束外延生长 N 极性 GaN

摘要 采用氨分子束外延法研究了N极性GaN的同质外延生长。改变 V/III 通量比和生长温度的系统生长研究表明，实现形态光滑薄膜的最强因素是生长温度；N 面薄膜需要在大约 100°C 或比 Ga 面薄膜更高的温度下生长，以提供相同的金属通量。光滑的 N 面薄膜也可以在仅比 Ga 面薄膜高 50°C 的温度下生长，尽管是在降低的金属通量下。过高的生长温度和过低的金属通量会导致位错介导的表面点蚀。还通过二次质量离子光谱研究了此类膜的无意杂质掺入，并且最重要的是揭示了10 17 中间到10 18 cm -3 中间范围内的氧含量。