Medium-scale flexible integrated circuits based on 2D semiconductors

Abstract

Two-dimensional (2D) semiconductors, combining remarkable electrical properties and mechanical flexibility, offer fascinating opportunities for flexible integrated circuits (ICs). Despite notable progress, so far the showcased 2D flexible ICs have been constrained to basic logic gates and ring oscillators with a maximum integration scale of a few thin film transistors (TFTs), creating a significant disparity in terms of circuit scale and functionality. Here, we demonstrate medium-scale flexible ICs integrating both combinational and sequential elements based on 2D molybdenum disulfide (MoS₂). By co-optimization of the fabrication processes, flexible MoS₂ TFTs with high device yield and homogeneity are implemented, as well as flexible NMOS inverters with robust rail-to-rail operation. Further, typical IC modules, such as NAND, XOR, half-adder and latch, are created on flexible substrates. Finally, a medium-scale flexible clock division module consisting of 112 MoS₂ TFTs is demonstrated based on an edge-triggered Flip-Flop circuit. Our work scales up 2D flexible ICs to medium-scale, showing promising developments for various applications, including internet of everything, health monitoring and implantable electronics.