Open AccessMillimeter-Scale Continuous Film of MoS2 Synthesized Using a Mo, Na, and Seeding Promoter-Based Coating as a Solid Precursor
Author(s) -
Maddumage Don Sandeepa Lakshad Wimalananda,
Jae-Kwan Kim,
Sung Woon Cho,
Ji-Myon Lee
Publication year - 2021
Publication title -
acs omega
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.779
H-Index - 40
ISSN - 2470-1343
DOI - 10.1021/acsomega.1c05052
Subject(s) - materials science , monolayer , seeding , coating , molybdenum disulfide , chemical vapor deposition , crystal (programming language) , nanoscopic scale , millimeter , nanotechnology , chemical engineering , optoelectronics , composite material , optics , physics , aerospace engineering , computer science , engineering , programming language
While the chemical vapor deposition technique can be used to fabricate 2D materials in a larger area, materials like MoS 2 have limited controllability due to their lack of self-controlling nature. This article presents a new technique for synthesizing a void-free millimeter-scale continuous monolayer MoS 2 film through the diffusion of a well-controlled Mo, Na, and seeding promoter-based coating under a low-pressure N 2 atmosphere. Compared to the conventional method, this technique provides precise control of solid precursors, where MoS 2 grows next to the coating. At 800 °C, the synthesized MoS 2 showed a uniform single-layer MoS 2 film; however, a Na-free coating showed nanoscale voids and poor crystal quality, which are attributed to a higher edge-attachment barrier that slows down the MoS 2 lateral growth. The synthesized MoS 2 with Na-containing solution showed an intense PL peak with a 1.86 eV band gap. Even at the relatively low temperature of 700 °C, compared to the Na-excluded condition, MoS 2 showed almost two times higher area coverage with a comparatively larger crystal size. This finding may assist in the future development of MoS 2 -based electronic and optoelectronic devices such as transistors and photodetectors.