Toward selective transfer of CVD monolayer WS2 based on laser-cutting dedicated FET applications

Abstract

To date, the thin tungsten disulfide (WS2) with its tunable band gap structure has renewed increasing attention in microelectronic design owing to its favorable electronic and optoelectronic properties. Chemical vapor deposition (CVD) as a bottom-up growth method of WS2 is well known for its compatibility with the mature integrated circuit technology (CMOS), making it the most promising method to synthesize large-area and high-quality WS2 crystals and uplift its integration into microelectronic applications-based field-effect transistor (FET). However, ultra-clean transfer of CVD-grown monolayer tungsten disulfide (WS2) using polymer-assisted transfer with defect-free is still crucial for large-area WS2devices' high performance. Additionally, the inhomogeneous distribution of the CVD-grown WS2 drastically hampers the widespread usage of WS2-based FET applications due to the alignment difficulty during the FET microfabrication. In this work, we present a new transfer insight of CVD grown WS2 toward selective transfer and single chip multiple usages based on laser-cutting and conventional PMMA wet etching transfer. The transferred WS2 surface structure and morphology were well characterized using optical microscopy, PL, Raman spectroscopy, and AFM, confirming the ultraclean and crackles of the transferred WS2 crystals. While the WS2 FET developed following this strategy led to high carrier mobility and on/off ratio of 71 cm2/Vs and 105, respectively. The work described in this paper could broaden the CVD synthesis and transfer of WS2 and their promising microelectronics application-based field-effect transistor.

Unleashing the potential of tungsten disulfide: Current trends in biosensing and nanomedicine applications

“…The exploration of 2D materials gained momentum following the identification of graphene, composed of a carbon sheet only one atom thick [ 1 , 2 ]. Concurrently, the discovery and exploration of transition metal dichalcogenides (TMDCs) in the 1990s led to their increasing importance across various fields, including solar energy conversion, batteries, photodetectors, transistors, and surface coatings [ [3] , [4] , [5] , [6] ]. In recent years, TMDCs have also garnered attention in the biomedical field due to their high X-ray attenuation ability for radiotherapy and tomography, large exciton binding energy, strong photoluminescence, layer-dependent band gap, and good stability in ambient [ [7] , [8] , [9] , [10] ].…”