Ultraviolet emission characteristics of cubic (c-) GaN enabled through hexagonal-to-cubic phase transition are reported. Substrate patterning and material growth are shown to affect phase purity and emission characteristics of c-GaN as studied by electron backscatter diffraction, and photo- and cathodoluminescence, respectively. Raman study shows a tensile strain in the c-GaN. Time-resolved photoluminescence reveals c-GaN band edge emission decay time of 11 ps. The ultraviolet emissions from both phases of GaN are linearly polarized in the same direction, which is along the ⟨112̅0⟩ and ⟨110⟩ directions of hexagonal GaN and c-GaN, respectively. Temperature-dependent (5.7 to 280 K) cathodoluminescence studies reveal an internal quantum efficiency of ∼29% at room temperature along with intrinsic and extrinsic defect energy levels of ∼124 and ∼344 meV, respectively, of the phase-transition c-GaN. Using the IQE value and carrier decay lifetime, a radiative lifetime of 38 ps is extracted. Overall, photonic properties of phase-transition c-GaN and their dependence on substrate patterning and material growth are reported.

中文翻译：

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纳米图案化Si（100）上集成的相变立方GaN的高内部量子效率紫外发射

报道了通过六方相到立方相变实现的立方（c-）GaN的紫外发射特性。分别通过电子背散射衍射，光和​​阴极发光研究表明，基板构图和材料生长会影响c-GaN的相纯度和发射特性。拉曼研究显示了c-GaN中的拉伸应变。时间分辨的光致发光显示c-GaN带边缘发射衰减时间为11 ps。来自GaN两相的紫外线发射沿相同方向线性偏振，该方向分别沿着六边形GaN和c-GaN的⟨112̅0⟩和⟨110⟩方向。与温度有关的（5.7至280 K）阴极发光研究表明，室温下内部量子效率为〜29％，固有和非固有缺陷能级分别为〜124和〜344 meV，分别是相变c-GaN的。使用IQE值和载波衰减寿命，可以提取38 ps的辐射寿命。总体而言，已报道了相变c-GaN的光子特性及其对衬底图案和材料生长的依赖性。