Statistical Study on the Schottky Barrier Reduction of Tunneling Contacts to CVD Synthesized MoS2

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• 作者：Seunghyun Lee ; Alvin Tang ; Shaul Aloni ; H.-S. Philip Wong
• 刊名：Nano Letters
• 出版年：2016
• 出版时间：January 13, 2016
• 年：2016
• 卷：16
• 期：1
• 页码：276-281
• 全文大小：399K
• ISSN：1530-6992

文摘

Creating high-quality, low-resistance contacts is essential for the development of electronic applications using two-dimensional (2D) layered materials. Many previously reported methods for lowering the contact resistance rely on volatile chemistry that either oxidize or degrade in ambient air. Nearly all reported efforts have been conducted on only a few devices with mechanically exfoliated flakes which is not amenable to large scale manufacturing. In this work, Schottky barrier heights of metal-MoS<sub>2sub> contacts to devices fabricated from CVD synthesized MoS<sub>2sub> films were reduced by inserting a thin tunneling Ta<sub>2sub>O<sub>5sub> layer between MoS<sub>2sub> and metal contacts. Schottky barrier height reductions directly correlate with exponential reductions in contact resistance. Over two hundred devices were tested and contact resistances extracted for large scale statistical analysis. As compared to metal-MoS<sub>2sub> Schottky contacts without an insulator layer, the specific contact resistivity has been lowered by up to 3 orders of magnitude and current values increased by 2 orders of magnitude over large area (>4 cm<sup>2sup>) films.