Design of Versatile Top-Down Transfer by Thermal Release Tape/Poly(methyl methacrylate) (TRT/PMMA) Bi-Supporting...

A top-down transfer process is developed via a rolling process associated with thermal release tape/poly(methyl methacrylate) (PMMA) bi-supporting layers to realize large-scale transfer processes on transition metal dichalcogenide materials. A 2-inch MoS₂ thin film transferred on SiO₂/Si substrates with high integrity and a yield of ≈99% can be successfully achieved via the proposed process. MoS₂-based transistors with a transferred Au thin film as the contact electrode indicate a lower contact resistance of 8.4 kΩ with improved mobility and a higher on/off ratio compared with that of the MoS₂-based transistors with the evaporated Au thin film as the contact electrode. By applying the difference in adhesion force between metal oxides and metal on MoS₂ and PMMA surfaces, the selective transfer of MoS₂ films can be demonstrated. Furthermore, all-transferred MoS₂-based transistor arrays are demonstrated by combining the selectively transferred MoS₂ film as the channel material and the transferred Au thin films as the contact electrode, which results in uniform electrical properties featuring a carrier mobility of 10.45 cm² V^-1 s^-1, a subthreshold swing of 203.94 mV dec^-1, a normalized I _on of 8.3 μA μm^-1, and an on/off ratio of 10⁵.