Carrier recombination dynamics in III-N photodetectors

III-N 光电探测器中的载流子复合动力学

• 批准号: 2341747
• 负责人: Leonid Chernyak
• 金额: $ 38.72万
• 依托单位: The University of Central Florida Board of Trustees
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-05-01 至 2027-04-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2341747&HistoricalAwards=false
• 关键词: Carrier; recombination; dynamics; III; photodetectors

Ultraviolet photodetectors have many uses, such as chemical and biological analysis or flame detection. Damage by energetic particles degrades the sensitivity of ultraviolet photodetectors in harsh radiation environments. This project will study techniques for recovery of photodetectors based on gallium nitride (GaN). This aim will be achieved by electrical tailoring of GaN fundamental properties, the electron lifetime and diffusion length, by in-situ charge injection under applied voltage. Photodetector sensitivity will recover completely and return to the original state prior to irradiation. The project will advance the fundamental understanding of the nature of point and extended defects in GaN-based semiconductors and devices. The project will integrate research and education at the graduate and undergraduate levels and features an active industrial partner.Technical: This project focuses on electrical mitigation of radiation-induced defects by charge injection into ultraviolet photodetectors based on gallium nitride (GaN). The ultimate aim is to produce radiation hard and efficient devices. The project hinges on the PI's previous findings that charge injection into p-type GaN leads to considerable changes in the material's fundamental electronic properties, particularly the carrier lifetime and diffusion length. These changes result in an order of magnitude enhancement of the photodetector response (quantum efficiency). It is therefore possible to improve performance of photodetectors, affected by radiation, using short pulses of solid-state forward-bias charge injection into GaN p-i-n devices. The project will lead to a better understanding of the interaction between wide band gap semiconductors and highly energetic particles, including electrons, gamma-ray photons and protons, as well as of the nature of radiation-induced defects. Charge injection will result in enhanced minority electron diffusion length in the top p-type absorption layer of a photodetector, thus increasing the quantum efficiency for the device and "healing" the adverse impact of highly energetic particles. A unique combination of electrical and optical studies in the PI’s lab will shed light on the mechanism, which is responsible for the effect of interest. Studies of minority carrier lifetime and diffusion length will be carried out in independent experiments using ultrafast time-resolved cathodoluminescence and electron beam-induced current at various temperatures. Polychromatic continuous-wave cathodoluminescence will be employed for assessment of irradiation impact on threading dislocation density in GaN. Finally, the ultimate goal of this project is to correlate charge injection regimes (current; voltage; duration) and irradiation doses, thus proceeding towards control of photodetector performance and recovery from radiation damage by purely electrical means.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

紫外光电探测器有许多用途，例如化学和生物学分析或火焰检测。能量颗粒的损害降低了Harmsh辐射环境中紫外线光电探测器的敏感性。该项目将研究基于氮化炮（GAN）的光电探测器回收的技术。通过在施加电压下通过原位电荷注入的GAN基本特性，电子寿命和扩散长度的电裁缝，电子寿命和扩散长度将实现此目标。光电探测器灵敏度将完全恢复，并在辐照之前恢复到原始状态。该项目将进一步了解基于GAN的半导体和设备中点的性质和扩展缺陷的基本理解。该项目将在研究生和本科层面上整合研究和教育，并具有活跃的工业合作伙伴。技术：该项目的重点是通过电荷注入基于硝酸盐（GAN）的紫外线光电探测器对辐射引起的缺陷进行电力缓解。最终目的是生产辐射硬有效的设备。该项目取决于PI先前的发现，即对P型GAN充电会导致材料的基本电子性质，尤其是载体寿命和扩散长度的大幅变化。这些变化导致光电探测响应（量子效率）的数量级增强。因此，使用固态前向偏置电荷的短脉冲注入到GAN P-I-N设备中，可以改善受辐射影响的光电探测器的性能。该项目将更好地理解宽带隙半导体与高能颗粒之间的相互作用，包括电子，伽马射线照片和质子，以及辐射引起的缺陷的性质。电荷注入将导致在光电探测器的顶部P型抽象层中增强的少数电子扩散长度，从而提高了设备​​的量子效率，并“愈合”高能颗粒的不利影响。 PI实验室中电气和光学研究的独特组合将阐明该机制，这是造成关注的影响的。少数载体寿命和扩散长度的研究将在独立的实验中使用超快分辨的阴极发光和电子束诱导的各种温度下的电流进行研究。将采用多色连续波发光来评估辐照对gAN中螺纹脱位密度的影响。最后，该项目的最终目的是将冲锋注入制度（电流；电压；持续时间）和辐照剂量相关联，从而朝着控制光电探测器的性能和通过纯电气手段从辐射损害中恢复的恢复。该奖项反映了NSF的法规任务，并被认为是通过基金会的知识优点的评估来进行评估，并通过评估来审查了智力优点和广泛的影响。