Rapid Growth of Monolayer MoSe₂ Films for Large‐Area Electronics

Abstract

The large‐scale growth of semiconducting thin films on insulating substrates enables batch fabrication of atomically thin electronic and optoelectronic devices and circuits without film transfer. Here an efficient method to achieve rapid growth of large‐area monolayer MoSe2 films based on spin coating of Mo precursor and assisted by NaCl is reported. Uniform monolayer MoSe2 films up to a few inches in size are obtained within a short growth time of 5 min. The as‐grown monolayer MoSe2 films are of high quality with large grain size (up to 120 µm). Arrays of field‐effect transistors are fabricated from the MoSe2 films through a photolithographic process; the devices exhibit high carrier mobility of ≈27.6 cm2 V–1 s–1 and on/off ratios of ≈105. The findings provide insight into the batch production of uniform thin transition metal dichalcogenide films and promote their large‐scale applications.

Synergistic Effects of Plasmonic Au Nanoislands on a MoSe2 Nanoflake/ZnO Nanorod Heterostructure for an Enhanced Broadband Photoresponse

“…From the AFM micrograph presented in Figure S2, SI, the thickness of the nanoflakes is found to be ∼6−7 nm containing a few layers only. 35 Considering that the thinning of MoSe 2 has taken place from all three dimensions, these microscopic studies confirm the 2D nature of the resultant MoSe 2 nanoflakes. The morphology of the vertically standing ZnO NRs examined through SEM micrographs (top view) is presented in Figure 1c,d in different magnifications, and the average diameter and length of the NRs are estimated to be in the range of ∼70−200 nm and ∼800−850 nm, respectively.…”

“…The sample has been further characterized by energy-dispersive X-ray (EDX) spectroscopy, revealing the superior crystalline quality without significant amount of impurities and oxidation, as can be seen from Figure S1b, SI. From the AFM micrograph presented in Figure S2, SI, the thickness of the nanoflakes is found to be ∼6–7 nm containing a few layers only . Considering that the thinning of MoSe 2 has taken place from all three dimensions, these microscopic studies confirm the 2D nature of the resultant MoSe 2 nanoflakes.…”

Chemical Vapor Deposition of 4 Inch Wafer‐Scale Monolayer MoSe2

“…Top-down methods like mechanical exfoliation and chemical exfoliation [12,13] are not able to achieve large-scale uniform monolayer films. With the development of bottom-up methods, various techniques have been developed to synthesize monolayer MoSe 2 so far, including chemical vapor deposition (CVD), [10,[14][15][16][17][18][19] metal-organic chemical vapor deposition (MOCVD), [20] molecular beam epitaxy (MBE), [11] atomic-layer deposition (ALD), [21] and selenization of metal or metal compounds. [22] In general, selenium has a lower reaction activity than sulfur, the growth of monolayer MoSe 2 is more difficult than that of monolayer MoS 2 , [23][24][25] and as-grown monolayer MoSe 2 at a large scale is usually not uniform.…”

Phase-Field Modeling of Chemical Vapor-Deposited 2D MoSe2 Domains with Varying Morphology for Electronic Devices and Catalytic Applications

“…Experimental studies have shown that changes in the growth parameters such as growth temperature, precursor flux, choice of carrier gases, etc., produces 2D domains of different shapes and sizes, and of varying structural qualities. 21,22,33,34 Atmospheric pressure CVD (APCVD) growth of TMDs has demonstrated diverse domain morphologies, e.g., hexagonal, triangular, truncated hexagonal/triangular, star-shape, etc. indicative of the growth following the 6-fold or the 3-fold crystal symmetries corresponding to 2H crystal phase.…”