Polarity determination of polar and semipolar (112¯2) InN and GaN layers by valence band photoemission spectroscopy
Polarity determination of polar and semipolar (112¯2) InN and GaN layers by valence band photoemission spectroscopy
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DOI：
10.1063/1.4828487
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发表时间：
2013-11
影响因子：
3.2
通讯作者：
D. Skuridina;D. V. Dinh;B. Lacroix;P. Ruterana;M. Hoffmann;Z. Sitar;M. Pristovsek;M. Kneissl;P. Vogt
中科院分区：
文献类型：
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作者：
D. Skuridina;D. V. Dinh;B. Lacroix;P. Ruterana;M. Hoffmann;Z. Sitar;M. Pristovsek;M. Kneissl;P. Vogt
我们证明，极性（0001），（0001 <$）和半极性（112 <$2）InN和GaN薄膜的极性可以确定的价带X射线光电子能谱（XPS）。通过湿法腐蚀和会聚束电子衍射证实了膜层的极性。与这两种技术不同，XPS是一种非破坏性方法，不受表面氧化或粗糙度的影响。在用AlKα X射线辐射记录的光谱中，观察到N极性层和III族极性层的价带态强度不同。价带态的最高强度在InN的3.5 eV和GaN的5.2 eV处与III族极性相关，而InN的6.7 eV和GaN的9.5 eV处的最高强度与N极性相关。在0.05的显著性水平下，发现III组和N组极性方向的峰之间的差异具有统计学显著性。半极性（112 <$2）InN和GaN层的极性可以通过记录价带pH值来确定。
We demonstrate that the polarity of polar (0001), (0001¯) and semipolar (112¯2) InN and GaN thin layers can be determined by valence band X-ray photoemission spectroscopy (XPS). The polarity of the layers has been confirmed by wet etching and convergent beam electron diffraction. Unlike these two techniques, XPS is a non-destructive method and unaffected by surface oxidation or roughness. Different intensities of the valence band states in spectra recorded by using AlKα X-ray radiation are observed for N-polar and group-III-polar layers. The highest intensity of the valence band state at ≈3.5 eV for InN and ≈5.2 eV for GaN correlates with the group-III polarity, while the highest intensity at ≈6.7 eV for InN and ≈9.5 eV for GaN correlates with the N-polarity. The difference between the peaks for the group-III- and N-polar orientations was found to be statistically significant at the 0.05 significance level. The polarity of semipolar (112¯2) InN and GaN layers can be determined by recording valence band ph...