Large-scale flexible and transparent electronics based on monolayer molybdenum disulfide field-effect transistors

Atomically thin molybdenum disulfide (MoS 2 ) is a promising semiconductor material for integrated flexible electronics due to its excellent mechanical, optical and electronic properties. However, the fabrication of large-scale MoS 2 -based flexible integrated circuits with high device density and performance remains a challenge. Here, we report the fabrication of transparent MoS 2 -based transistors and logic circuits on flexible substrates using four-inch wafer-scale MoS 2 monolayers. Our approach uses a modified chemical vapour deposition process to grow wafer-scale monolayers with large grain sizes and gold/titanium/gold electrodes to create a contact resistance as low as 2.9 kΩ μm −1 . The field-effect transistors are fabricated with a high device density (1,518 transistors per cm 2 ) and yield (97%), and exhibit high on/off ratios (10 10 ), current densities (~35 μA μm −1 ), mobilities (~55 cm 2 V −1 s −1 ) and flexibility. We also use the approach to create various flexible integrated logic circuits: inverters, NOR gates, NAND gates, AND gates, static random access memories and five-stage ring oscillators. Wafer-scale monolayers of MoS 2 can be used to create flexible transistors and circuits that exhibit on/off ratios of 10 10 , current densities of ~35 μA μm −1 and mobilities of ~55 cm 2 V −1 s −1 .