稀土掺杂硅基中红外光电探测材料及器件性能研究

Photdetector has important applications in city irradiation managing and environment monitoring including meteorological remote sensing, optoelectronic alarm, power crusing, fire monitoring and so on. Development of non-toxic, light-weighted, fast responding and high performance mid-infrared photodetetor is one of the very important research area for infrared science and technology. In this project, high performance mid-infrared photodetector with long detecting wavelength and high working temperature will be developed through optimizing the design and fabrication of silicon materials and devices. Rare earth elements will be adopted to dope silicon material to realize the energy band coupling of silicon and the rare earths. Mid-infrared response will be realized due to the direct transition between energy band of Si and rare earth atomic levels. Improved PN junction and npn transistor structure will be designed to avoid the disadvantage of high leakage current existing in the traditional PN junction structure photodetector. The effect of rare earth doping concentration and dopant distribution on the performance of device will be fully studied. Maximum light illumination, small leakage current, high responsivity and high signal-to-noise ratio will be achieved through optimizing the device structure and materials parameters. Working temperature and responsivity of the photodetector will be largely elevated with the help of intrinsic gain from the transistor structure. With the expanding of detecting wavelength to mid-infrared region and elevating of working temperature to room temperature, the silicon based mid-infrared photodetecotr could be widely applied in civil and military environment with lower cost, less toxicity and more convenient device fabricating technology since it is compatible with the industrial ultra large scale integration processing. The optimizing of the materials/devices and the clarifying of the according mechanism will offer solid theoretical and experimental foundation for the silicon based mid-infrared photodetector industrialization.

中红外探测器件在智慧城市辐射管理、环境监控等领域有重要应用。发展无有害元素、轻量化、高速响应和高性能中红外探测器件是红外领域的重要研究方向。本项目拟通过研究多种稀土原子在硅晶体场中的能级耦合，实现硅基价带电子与稀土原子轨道能级之间直接光吸收跃迁，获得高响应度硅基中红外光探测性能，扩展红外探测波段至中远红外区域。设计与制备二极管和三极管光电探测器件，研究稀土掺杂离子浓度、分布位置对器件性能的影响。探寻最大化光输入、降低漏电流、提高响应信噪比的关键器件结构和参数设计。利用三极管的本征增益来放大红外探测信号，提升器件工作温度，获得高性能光电响应。为设计开发与集成电路工艺兼容的室温高效硅基中红外探测器件，拓展其在军事和民用的应用提供坚实的理论和实验基础。

中红外探测器件在智慧城市辐射管理、环境监控等领域有重要应用。发展无有害元素、轻量化、高速响应和高性能中红外探测器件是红外领域的重要研究方向。本项目成功通过稀土离子原子能级与硅晶体能级之间的耦合，实现了电子在耦合能级间的跃迁，突破了传统硅带隙的限制，将硅基红外探测波段拓宽至近、中红外领域，截止波长为5.1 μm左右。通过台面刻蚀的工艺，降低其漏电流，提升探测率。刻蚀后Ce掺杂探测器1.3 μm波长对应的探测率在80 K温度下可达4.53 × 1011 cm•Hz1/2/W，为刻蚀前的300倍；300 K温度下为1.32 × 108 cm•Hz1/2/W，是刻蚀前的3倍。温度系数在1300 nm处为+0.161% ºC-1，在1550 nm 处为+0.308% ºC-1，表现出良好的温度稳定性。在200 K都保持对5 μm波长的良好探测响应，将中红外探测提升至可电制冷温度。本项目经过四年的执行期，发表了15篇高水平SCI论文，其中包括EEM、CEJ等具有国际影响力期刊，申请6件发明专利，其中授权3件。