Fast-Response Inverter Arrays Built on Wafer-Scale MoS₂ by Atomic Layer Deposition

The wafer-scale integration of the downscaled devices such as transistors based on two-dimensional (2D) transition metal dichalcogenide (TMD) has attracted great attention in recent years. Such integration is also a significant step towards the system-level application of these novel low-dimensional semiconductors. Yet, so far, functional logic circuits based on the 2D TMDs have rarely been reported, largely because of the absence of an effective approach for large-scale TMD synthesis and the unsatisfactory elementary logic cell performance. In this work, n-type inverter (NOT gate circuit) arrays have been fabricated based on a wafer-scale 2D molybdenum disulfide (MoS₂) thin film which is grown by atomic layer deposition (ALD). High-quality crystallinity and excellent wafer-level uniformity have been successfully achieved. The n-type inverter array exhibits a fast response with 50 Hz inverse-frequency. The impact of the device geometry on the inverter performance has also been characterized by designing various width ratio between the load and pull-down transistors. These results open up an attractive approach to realize the practical application of wafer-scale 2D MoS₂ in logic and circuit systems.