Semiconductor p–n junctions are the elementary building blocks of most electronic and optoelectronic devices. The need for their miniaturization has fuelled the rapid growth of interest in two-dimensional (2D) materials. However, the performance of a p–n junction considerably degrades as its thickness approaches a few nanometres and traditional technologies, such as doping and implantation, become invalid at the nanoscale. Here we report stable non-volatile programmable p–n junctions fabricated from the vertically stacked all-2D semiconductor/insulator/metal layers (WSe₂/hexagonal boron nitride/graphene) in a semifloating gate field-effect transistor configuration. The junction exhibits a good rectifying behaviour with a rectification ratio of 10⁴ and photovoltaic properties with a power conversion efficiency up to 4.1% under a 6.8 nW light. Based on the non-volatile programmable properties controlled by gate voltages, the 2D p–n junctions have been exploited for various electronic and optoelectronic applications, such as memories, photovoltaics, logic rectifiers and logic optoelectronic circuits.

中文翻译：

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二维非易失性可编程p–n结

半导体PN结是大多数电子和光电设备的基本构建模块。对它们的小型化的需求推动了对二维（2D）材料的兴趣的快速增长。但是，ap–n结的性能随着其厚度接近几纳米而大大降低，并且传统技术（例如掺杂和注入）在纳米级上变得无效。在这里，我们报告了由垂直堆叠的全二维半导体/绝缘体/金属层（WSe ₂ /六方氮化硼/石墨烯）以半浮栅场效应晶体管配置制成的稳定的非易失性可编程p–n结。该结表现出良好的整流性能，整流比为10 ⁴光伏特性，在6.8 nW光下的功率转换效率高达4.1％。基于栅极电压控制的非易失性可编程属性，二维p–n结已被用于各种电子和光电应用，例如存储器，光伏，逻辑整流器和逻辑光电电路。