Enhancing Ga₂O₃-based heterojunction solar-blind photodetectors is crucial for achieving high-performance UV light detection. A key factor for such heterojunctions is the development of a high-quality p-type layer to improve hole extraction and transport after illumination. Among the critical parameters influencing photodetector performance is hole mobility, which plays a significant role in efficient charge extraction. In this study, we utilized Li_yNi_1-x-yMg_xO with varying magnesium fractions, which demonstrated significantly improved hole mobility. For Li_yNi_1-x-yMg_xO without magnesium, we observed a low hole mobility of approximately 0.798 cm²·V^-1·s^-1, with a hole density of 1.72 × 10¹⁸ cm^-3. By incorporating Mg into the structure, hole mobility and density increased, reaching values of 4.73 cm²·V^-1·s^-1 and 6.85 × 10¹⁷ cm⁻³, respectively, for an 8.57% atomic percentage of magnesium. At a higher magnesium content of 17.08%, the mobility and hole concentration further improved to 33.39 cm²·V^-1·s^-1 and 3.15×10¹⁶ cm^-3, respectively. X-ray photoelectron spectroscopy analysis revealed that the O-Ni bond component decreased while the O-Mg component increased with higher magnesium concentrations, indicating that magnesium successfully replaced nickel atoms in the lattice. Surface roughness analysis using atomic force microscopy and the formation of an interfacial layer in the Li_yNi_1-x-yMg_xO/β-Ga₂O₃ interface were studied using transmission electron microscopy. We observed that the formed interfacial thickness decreased with increasing Mg content, particularly at 17.80%. The photodetector based on Li_yNi_1-x-yMg_xO with 17.80% magnesium exhibited the highest performance, with a responsivity of 31.215×10³ mA·W^-1, a detectivity of 4.71×10¹⁴ Jones, and rise and decay times of 50 ms and 179 ms, respectively. Additionally, the external quantum efficiency reached 641%. These results confirm that higher hole mobility plays a critical role in enhancing photodetector performance. Simulations using Technology Computer-Aided Design further demonstrated that the fast hole extraction with enhanced hole mobility, validating the experimental findings.

中文翻译：

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高迁移率 P 型 LiyNi1-x-yMgxO 与 Ga2O3 光电探测器集成，可增强响应性、探测性和快速响应时间

增强基于 Ga₂O₃ 的异质结日盲光电探测器对于实现高性能紫外光检测至关重要。这种异质结的一个关键因素是开发高质量的 p 型层，以改善照明后的空穴提取和传输。影响光电探测器性能的关键参数之一是空穴迁移率，它在高效电荷提取中起着重要作用。在这项研究中，我们使用了具有不同镁分数的 Li_yNi_1-x-yMg_xO，这表明空穴迁移率显着提高。对于不含镁的 Li_yNi_1-x-yMg_xO，我们观察到约 0.798 cm²·^V-1·^s-1，孔密度为 1.72 ×^{10 18 cm-3}。通过将 Mg 掺入结构中，空穴迁移率和密度增加，达到 4.73 cm²·^V-1·^s-1 和 6.85 × 10¹⁷ cm⁻³，镁的原子百分比为 8.57%。当镁含量较高（17.08%）时，迁移率和空穴浓度进一步提高至 33.39 cm²·^V-1·^s-1 和 3.15×10 ^{分别为 16 cm-3}。X 射线光电子能谱分析显示，随着镁浓度的增加，O-Ni 键成分减少，而 O-Mg 成分增加，表明镁成功地取代了晶格中的镍原子。使用透射电子显微镜研究了使用原子力显微镜进行的表面粗糙度分析以及在 Li_yNi_1-x-yMg_xO/β-Ga₂O₃ 界面中形成界面层的情况。 我们观察到形成的界面厚度随着 Mg 含量的增加而减小，尤其是在 17.80% 时。基于 Li_yNi_1-x-yMg_xO 且镁含量为 17.80%的光电探测器表现出最高的性能，响应度为 31.215×10³ mA·^W-1，探测率为 4.71×10¹⁴ Jones，上升和衰减时间分别为 50 ms 和 179 ms。此外，外部量子效率达到 641%。这些结果证实，更高的空穴迁移率在提高光电探测器性能方面起着关键作用。使用技术计算机辅助设计的模拟进一步证明，快速出孔和增强的孔移动性，验证了实验结果。