The Key Laboratory of Weak Light Nonlinear Photonics Ministry of Education, Teda Applied Physics Institute and School of Physics, Nankai University, Tianjin, 300071, China.
The 2011 Project Collaborative Innovation Center for Biological Therapy, Nankai University, Tianjin, 300071, China.
Adv Mater. 2018 Jan;30(2). doi: 10.1002/adma.201704653. Epub 2017 Nov 23.
Despite many decades of research of diodes, which are fundamental components of electronic and photoelectronic devices with p-n or Schottky junctions using bulk or 2D materials, stereotyped architectures and complex technological processing (doping and multiple material operations) have limited future development. Here, a novel rectification device, an orientation-induced diode, assembled using only few-layered black phosphorus (BP) is investigated. The key to its realization is to utilize the remarkable anisotropy of BP in low dimensions and change the charge-transport conditions abruptly along the different crystal orientations. Rectification ratios of 6.8, 22, and 115 can be achieved in cruciform BP, cross-stacked BP junctions, and BP junctions stacked with vertical orientations, respectively. The underlying physical processes and mechanisms can be explained using "orientation barrier" band theory. The theoretical results are experimentally confirmed using localized scanning photocurrent imaging. These orientation-induced optoelectronic devices open possibilities for 2D anisotropic materials with a new degree of freedom to improve modulation in diodes.
尽管已经对二极管进行了几十年的研究，这些二极管是使用体材料或二维材料的具有 p-n 或肖特基结的电子和光电子器件的基本组成部分，但刻板的架构和复杂的技术处理（掺杂和多种材料操作）限制了其未来的发展。在这里，研究了一种使用仅由几层黑磷 (BP) 组装而成的新型整流器件，即取向诱导二极管。其实现的关键是利用低维 BP 的显著各向异性，并沿不同的晶体取向急剧改变电荷输运条件。在十字形 BP、交叉堆叠 BP 结和堆叠具有垂直取向的 BP 结中，分别可以实现 6.8、22 和 115 的整流比。使用“取向势垒”能带理论可以解释其背后的物理过程和机制。使用局域扫描光电流成像实验验证了理论结果。这些基于取向的光电设备为具有新自由度的二维各向异性材料提供了可能，从而改善了二极管的调制。
