宽带隙半导体异质结超快位敏传感器的研究

The photoelectric position-sensitive detectors with fast relaxation time plays an irreplaceable role in accurate measurement on the relative distance and location of high-speed-moving objects. The present photoelectric position-sensitive detectors are mostly based on Si p-n junctions. The performance of these photoelectric position-sensitive detectors would decrease rapidly under the environment of strong sun shine. The ultraviolet position-sensitive detectors based on Silicon carbide (SiC) heterogeneous structure would be investigated in this project. SiC is one of the wide band-gap semiconductors, which has more outstanding advantages such as high electron mobility and high work temperature. The thin films, which have big work function and large resistivity, would be made based on SiC substrate. The lateral diffusion rate of light-excited carriers would be controlled by regulating the interface state between SiC substrate and film, aiming to implement the ultraviolet position-sensitive sensor with fast relaxation time. By growing the high-quality thin films and electrodes, the heterojunctions are fabricated. The influences of the interface state of heterojunctions on their photoelectric performance were investigated. Then the relations of interface state, microstructure, band structure, and the performance of photoelectric device, were explored to reveal the micromechanisms of fast relaxation time based on the heterojunctions. These research would be significant for guiding and forecasting the high-performance devices materials. Furthermore, it is helpful for developing the ultraviolet position-sensitive detectors with our proprietary intellectual property rights. These position-sensitive detectors could meet the requirements of fast relaxation time under the extreme conditions.

具有快速光电恢复响应的位敏传感器在准确测定高速运动物体的相对距离和位置等方面发挥着重要作用。目前的位敏传感器都是基于硅p-n结，在强阳光照射等极端环境下，这类位敏传感器性能急剧下降。本项目中，我们将开展基于SiC异质结紫外光电位敏传感器的研究。宽禁带半导体SiC具有高电子迁移率、高工作温度等突出优点。在SiC基片上制备具有较高功函数和电阻率的薄膜，通过调节SiC与薄膜间的界面状态来调控光生载流子的横向扩散速度，实现紫外光电位敏传感器的超快光电恢复响应。制备高质量的薄膜材料和电极，构建出异质结，探究异质结界面状态对光电性质的影响，建立起界面状态、微结构、能带结构与器件光电性能间的关系，揭示异质结超快光电恢复响应的微观机制，为寻找高性能的器件材料提供指导和预测，为研制适应于极端环境的快速光电恢复响应的紫外光电位敏传感器奠定重要的研究基础。

本项目主要是研究不同功函数和电阻率的薄膜材料与SiC等宽带隙半导体构造的异质结，开展异质结紫外光电特性以及高性能位敏传感器原型器件的探索和研究，建立起异质结界面状态、微结构、能带结构与器件光电性能间的关系，阐明影响横向光伏特性的微观机理并建立器件性能与辐照环境间的关系，其核心就是通过调节宽带隙半导体与薄膜间的界面状态来调控光生载流子在界面处的横向扩散速度，从而实现紫外光电位敏传感器的超快光电恢复响应。. 基于此，本项目主要开展了二维半导体薄膜异质结光电位敏传感器的研究、基于稀土镍酸盐薄膜的自供电紫外光电传感器和位敏传感器的研究、新型尖晶石氧化物p型薄膜半导体异质结紫外光电位敏传感器及二维图像传感器的研究、电子/质子辐照的空间环境下宽带隙半导体异质结紫外光电探测器稳定特性以及半导体异质结在储能器件上的应用研究等几个方面。在制备出光电位敏传感器原型器件的基础上，系统研究了不同功函数和电阻率的薄膜材料对异质结光电位敏传感器性能的影响，通过详细研究薄膜材料、半导体薄膜性质以及界面状态对异质结光电位敏传感器的影响，阐明了异质结界面状态对光生载流子横向扩散的影响机理。在此基础上，利用异质结侧向光伏对内建电场依赖度低的特性实现了高温高性能紫外光电二维图像传感器和空间自由光通信。氧化物薄膜半导体器件稳定性高及易于制备等优点，非常有利于提高直接光电器件的应用前景，这为紫外光电位敏传感器件的实用化提供了必要的研究基础。本项目圆满完成了设定的研究目标。在包括光学领域的顶刊Light：Science & Application等高水平杂志发表SCI论文15篇，授权国家发明专利3项，培养硕博研究生8名，获得黑龙江省高校自然科学奖二等奖1项（排名第1）。