ALD Encapsulation of CVD WS2 for Stable and High-Performance FET Devices

Abstract

Processing and characterization of double gate CVD WS2 devices are presented in this work. By combining H-2 plasma cleaning and trimethylaluminium (TMA) soak initiated ALD process, double gate (DG) WS2 devices with clean and high-quality interface is obtained, leading to significant improvement in hysteresis and mobility as compared with uncapped devices. Double gate modulation is demonstrated, showing enhanced gate control and better I-on as compared with single gate operation.