High-Performance Top-Gate Transistors of Two-Dimensional Semiconductors Enabled by Resist-Free Femtosecond Laser Etching

Two-dimensional (2D) transition metal dichalcogenides (TMDs) are promising candidates for next-generation integrated circuits. However, conventional patterning methods including photolithography and electron-beam lithography, often introduce chemical residues that can disturb the electrical properties of 2D materials. Direct laser etching technique is resist-free which avoids direct contact of the 2D materials between organic compounds. Here, we utilize controllable femtosecond laser etching to pattern MoS 2 and MoTe 2 , successfully fabricating back-gate 2D devices. This approach effectively circumvents the electron doping typically induced by photoresist residues in conventional lithography processes. Top-gate MoS 2 transistors with an on/off ratio exceeding 10 7 and negligible hysteresis were fabricated via laser etching technique. Statistical evaluations of 60 devices confirmed their superior performance, including reduced hysteresis, lower SS, and improved uniformity compared to transistors fabricated via lithography methods. This simple and reproducible approach for realizing top-gate transistors highlights the potential of 2D semiconductors for applications in large-scale integrated circuits.