紫外单光子探测技术无论是在国防还是民用领域都具有迫切的重要应用。本联合基金项目主要针对发展氮化物室温低噪声单光子雪崩探测器所面临的关键科学和技术问题，重点开展氮化物半导体材料二次横向外延生长机理、位错形成与湮灭机制以及不同类型位错对载流子高场输运的影响规律等基础科学问题研究，有针对性解决对器件有重要影响的材料问题；深入研究氮化物半导体载流子碰撞电离机理和极化与能带裁剪对载流子碰撞电离的调控作用，建立适合宽带隙氮化物半导体的载流子碰撞电离模型；揭示高场下载流子的隧穿与雪崩竞争机制以及主要噪声产生的物理机制，探索实现单光子探测的物理条件，发展低噪声、高增益的氮化物雪崩探测器设计理论，解决增益受限于隧穿暗电流等关键科学问题。发展场板、斜面终端结构、低损伤刻蚀、光电化学表面钝化等关键工艺，有效抑制器件暗电流。项目立足关键科学问题和核心技术的攻关，突破氮化物半导体室温低噪声单光子探测技术。

UV single-photon detection technique at room temperature has very important applications in the fields of military and civilian.Facing key scientific problems and technical bottlenecks of developing low-noise and single-photon GaN-based avalanche photodiodes, we will carry out the researches on growth mechanisms and kinetics of nitride lateral epitaxial overgrown, dislocation generation and annihilation mechanisms, and effect of dislocation on carrier transport under high electric field in order to overcome the difficulties in fabricating the low-dislocation-density nitride materials. The effects of heterostructure polarization, energy-band lineup are investigated and their relations are also established. The leakage models under high electric field and physical origins of noises are studied by analyzing the tunneling and avalanche mechanisms. The key device processes including field plane, slope mesa terminal, low-damage etching, and surface passivation are developed together with innovating device design and the state-of-the-art material growth in order to break through the low-noise and single-photon detection technique.