基于MoS2/WS2二维材料异质结的超薄柔性忆阻器研究

The discovery of two-dimensional (2D) materials brings great opportunities for the construction of ultrathin, flexible and high-performance memristors. To address the issues in 2D material growth/assembly and the fabrication of high-performance 2D material memristor, this project proposes to exploit the excellent characteristics of 2D material heterojunctions to develop an ultrathin and flexible metal/semiconductor/metal (MSM) type memristor, which could outperform the classical metal/insulator/metal (MIM) type memristor. The main research contents include the growth of high-quality 2D crystalline thin films and heterojunctions; studying the characteristics and mechanism of the memristive switching behavior in MoS2/WS2 heterojunctions; fabrication and test of ultrathin and flexible memristors. The project will focus on employing solid-phase growth method for single-step controlled growth of MoS2/WS2 heterojunctions; construction of new memristive switching mechanism for MoS2/WS2 heterojunctions, and realization of crossbar array of 2D material memristor. The project will produce important innovation on the memristive switching mechanism of 2D material memristors, and make original contributions to the field of ultrathin and flexible memristive materials and devices, laying a solid foundation to the development of high-performance memristors on both theoretical and technical aspects.

二维材料的发现为构建超薄柔性忆阻器带来了契机。针对二维材料生长集成工艺的不足和高性能二维材料忆阻器的缺乏，提出利用半导体二维材料异质结的优异忆阻特性构建一种超薄柔性金属/半导体/金属（MSM）型忆阻器，突破传统金属/绝缘体/金属（MIM）型忆阻器的性能局限。主要内容包括高品质二维材料和MoS2/WS2异质结的生长；MoS2/WS2异质结的忆阻特性和机理研究；基于碳纳米管/异质结/石墨烯结构的MSM型超薄柔性忆阻器的制作和测试。项目将重点探索如何利用快速固相硫化技术单步生长品质可控的MoS2/WS2二维材料异质结结构，并建立新型的MoS2/WS2异质结构忆阻机理模型，实现二维材料MSM型忆阻器交叉阵列的制造。本项目将在二维材料忆阻机理方面产生重要的理论创新，在探索超薄柔性忆阻功能材料和二维材料忆阻器方面取得原创性成果，为我国高性能忆阻器的发展奠定坚实的理论和技术基础。

二维材料的发现为构建超薄、柔性和具有高稳定性的忆阻器带了契机。而相关忆阻机理理论的缺乏和成本高昂的二维材料生长工艺是阻碍器件发展的两大关键问题。本项目开发了新型二维材料制备工艺，通过对固相前驱体金属原子层的高温硫化，实现了2英寸晶圆级的过渡金属硫化物硫化钼（MoS2）和硫化钨（WS2）的制备，并通过飞秒激光与材料作用产生的非线性光学特性对材料表面形貌、层数和晶轴取向等进行了检测。另外，本项目开展了过渡金属硫化物忆阻特性的研究，制备了以超薄的WS2/MoS2异质结作为忆阻器功能层的忆阻器件，并研究了二维材料异质结忆阻器的工作机理，这种基于金属-半导体异质结-金属（MHM）架构的忆阻器有效地减少了传统金属-绝缘体-金属（MIM）结构忆阻器跳变过程中的随机性，使得器件性能更加稳定。本研究表明以二维材料异质结为主体的忆阻器架构不仅能实现稳定、超薄和低功耗的忆阻器制作，其材料本身还兼具柔性、透明和光电响应等特性，有望成为构建未来人工智能和类脑计算系统的基本元件。