Zhang Chengzhuang, Chen Yijing, Wang Meng, Guo Liliang, Qin Linling, Yang Zhenhai, Wang Changlei, Li Xiaofeng, Cao Guoyang
School of Optoelectronic Science and Engineering & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006, China.
Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province & Key Lab of Modern Optical Technologies of Education Ministry of China, Soochow University, Suzhou 215006, China.
ACS Nano. 2024 Jul 23;18(29):19303-19313. doi: 10.1021/acsnano.4c05329. Epub 2024 Jul 8.
Hybrid-dimensional heterojunction transistor (HDHT) photodetectors (PDs) have achieved high responsivities but unfortunately are still with unacceptably slow response speeds. Here, we propose a MASnI/MoS HDHT PD, which exhibits the possibility to obtain high responsivity and fast response simultaneously. By exploring the detailed photoelectric responses utilizing a precise optoelectronic coupling simulation, the electrical performance of the device is optimally manipulated and the underlying physical mechanisms are carefully clarified. Particularly, the influence and modulation characteristics of the trap effects on the carrier dynamics of the PDs are investigated. We find that the localized trap effect in perovskite, especially at its top surface, is primarily responsible for the high responsivity and long response time; moreover, it is normally hard to break such a responsivity-speed trade-off due to the inherent limitation of the trap effect. By synergistically coupling the photogating effect, trap effect, and gate regulation, we indicate that it is possible to achieve an enhancement of the responsivity-bandwidth product by about 3 orders of magnitude. This study facilitates a fine modulation of the responsivity-speed relationship of hybrid-dimensional PDs, enabling breaking the traditional responsivity-speed trade-off of many PDs.
混合维度异质结晶体管（HDHT）光电探测器（PD）已实现高响应度，但遗憾的是其响应速度仍慢得令人无法接受。在此，我们提出一种MASnI/MoS HDHT PD，它展现出同时获得高响应度和快速响应的可能性。通过利用精确的光电耦合模拟探索详细的光电响应，对该器件的电学性能进行了优化调控，并仔细阐明了其潜在的物理机制。特别地，研究了陷阱效应对PD载流子动力学的影响及调制特性。我们发现，钙钛矿中的局域陷阱效应，尤其是在其顶面，是高响应度和长响应时间的主要原因；此外，由于陷阱效应的固有局限性，通常很难打破这种响应度 - 速度的权衡。通过协同耦合光门控效应、陷阱效应和栅极调控，我们表明有可能将响应度 - 带宽积提高约3个数量级。这项研究有助于对混合维度PD的响应度 - 速度关系进行精细调制，从而打破许多PD传统的响应度 - 速度权衡。
