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Abstract Chemical vapor deposition (CVD)-grown monolayer (ML) molybdenum disulfide (MoS 2 ) is a promising material for next-generation integrated electronic systems due to its capability of high-throughput synthesis and compatibility with wafer-scale fabrication. Several studies have described the importance of Schottky barriers in analyzing the transport properties and electrical characteristics of MoS 2 field-effect-transistors (FETs) with metal contacts. However, the analysis is typically limited to single devices constructed from exfoliated flakes and should be verified for large-area fabrication methods. In this paper, CVD-grown ML MoS 2 was utilized to fabricate large-area (1 cm × 1 cm) FET arrays. Two different types of metal contacts (i.e. Cr/Au and Ti/Au) were used to analyze the temperature-dependent electrical characteristics of ML MoS 2 FETs and their corresponding Schottky barrier characteristics. Statistical analysis provides new insight about the properties of metal contacts on CVD-grown MoS 2 compared to exfoliated samples. Reduced Schottky barrier heights (SBH) are obtained compared to exfoliated flakes, attributed to a defect-induced enhancement in metallization of CVD-grown samples. Moreover, the dependence of SBH on metal work function indicates a reduction in Fermi level pinning compared to exfoliated flakes, moving towards the Schottky–Mott limit. Optical characterization reveals higher defect concentrations in CVD-grown samples supporting a defect-induced metallization enhancement effect consistent with the electrical SBH experiments.
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This content will become publicly available on October 23, 2026
Aging studies on chemical vapor deposition and mechanically exfoliated molybdenum disulfide flakes heated in ambient air
Abstract The structural integrity of atomically thin two-dimensional molybdenum disulfide (MoS2) is crucial for high-temperature applications, including nanoelectronics and optoelectronics. This study explores the structural stability and electrical performance, under extended thermal exposure in air, of MoS2flakes synthesized via chemical vapor deposition (CVD) and mechanical exfoliation. The MoS2flakes, both CVD-grown and mechanically exfoliated, were subjected to heating at 200 °C with a relative humidity of 60(±5)% for a prolonged period and investigated with atomic force microscopy and Raman spectroscopy. This study shows that CVD-grown flakes developed noticeable cracks after prolonged heating, whereas mechanically exfoliated flakes mostly retained their structural integrity. Also, both types of flakes showed a decrease in layer thickness and lateral size over time, with mechanically exfoliated flakes exhibiting a comparatively smaller reduction in substrate coverage area. In addition, MoS2-based two-terminal devices were subjected to heating at 150 °C for approximately 1100 h, and their electrical characterization revealed a steady rise in current during constant voltage (5 V) conditions. This study enhances our understanding of MoS2stability and provides guidance for improving the reliability of MoS2-based devices in high-temperature electronic applications.
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- Award ID(s):
- 2305013
- PAR ID:
- 10644151
- Publisher / Repository:
- IOP Publishing Ltd
- Date Published:
- Journal Name:
- Nanotechnology
- Volume:
- 36
- Issue:
- 43
- ISSN:
- 0957-4484
- Page Range / eLocation ID:
- 435701
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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