Energetics of H and NH_2 on GaN(1010) and implications for the origin of nanopipe defects
Energetics of H and NH_2 on GaN(1010) and implications for the origin of nanopipe defects
复制标题
GaN(1010)上H和NH_2的能量及其对纳米管缺陷起源的影响
DOI：
10.1103/physrevb.56.r4325
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发表时间：
1997
影响因子：
3.7
通讯作者：
J. Neugebauer
中科院分区：
文献类型：
--
作者：
J. Northrup;R. Felice;J. Neugebauer
我们提出了 H 端接 GaN(101\ifmmode\bar\else\textasciimacron\fi{}0) 表面形成能的第一性原理计算。计算表明，GaN(101\ifmmode\bar\else\textasciimacron\fi{}0) 上的 H 吸附将通过 Ga 和 N 悬空键对的饱和来进行，而不是通过仅占据一种类型的键合位点来进行。当$T=0,$时，完全H端接表面的表面能为0.02 eV/电池，而裸露表面的表面能为1.95 eV/电池。我们给出了 N-H 和 Ga-H 拉伸和弯曲特征频率的结果。 ${\mathrm{NH}}_{3}$ 通过形成 N-H 和 ${\mathrm{G}\mathrm{a}\ensuremath{-}\mathrm{N}\mathrm{H}}_{2}$ 键的解离吸附是放热的，并且在 $T=0 时将表面形成能降低到小于 0.1 eV。$ 这些结果对纳米管缺陷起源的影响GaN 进行了检查。
We present first-principles calculations of the formation energy for H-terminated GaN(101\ifmmode\bar\else\textasciimacron\fi{}0) surfaces. The calculations indicate that H adsorption on GaN(101\ifmmode\bar\else\textasciimacron\fi{}0) will proceed by saturation of pairs of Ga and N dangling bonds rather than through exclusive occupation of only one type of bonding site. At $T=0,$ the surface energy of the fully H-terminated surface is found to be 0.02 eV/cell, compared to 1.95 eV/cell for the bare surface. We present results for the N-H and Ga-H stretching and bending eigenfrequencies. Dissociative adsorption of ${\mathrm{NH}}_{3}$ via the formation of N-H and ${\mathrm{G}\mathrm{a}\ensuremath{-}\mathrm{N}\mathrm{H}}_{2}$ bonds is exothermic and reduces the surface formation energy to a value which is less than 0.1 eV at $T=0.$ The implications of these results for the origin of nanopipe defects in GaN are examined.