Potassium hydroxide treatment of layered WSe 2 with enhanced electronic performances

2D WSe -based electronic devices have received much research interest. However, it is still a challenge to achieve high electronic performance in WSe -based devices. In this work, we report greatly enhanced performances of different thickness WSe ambipolar transistors and demonstrate homogeneous WSe inverter devices, which are obtained by using a semiconductor processing-compatible layer removal technique chemical removal of the surface top WO layer formed by O plasma treatment. Importantly, monolayer WSe was realised after several consecutive removal processes, demonstrating that the single layer removal is accurate and reliable. After subsequent removal of the top layer WO by KOH, the fabricated WSe field-effect transistors exhibit greatly enhanced electronic performance along with the high electron and hole mobilities of 40 and 85 cm V s , respectively. Our work demonstrates that the layer removal technique is an efficient route to fabricate high performance 2D material-based electronic devices.