Wafer-Scale Synthesis of Reliable High-Mobility Molybdenum Disulfide Thin Films via Inhibitor-Utilizing Atomic Layer Deposition

Abstract

A reliable and rapid manufacturing process of molybdenum disulfide (MoS₂) with atomic-scale thicknesses remains a fundamental challenge toward its successful incorporation into high-performance nanoelectronics. It is imperative to achieve rapid and scalable production of MoS₂ exhibiting high carrier mobility and excellent on/off current ratios simultaneously. Herein, inhibitor-utilizing atomic layer deposition (iALD) is presented as a novel method to meet these requirements at the wafer scale. The kinetics of the chemisorption of Mo precursors in iALD is governed by the reaction energy and the steric hindrance of inhibitor molecules. By optimizing the inhibition of Mo precursor absorption, the nucleation on the substrate in the initial stage can be spontaneously tailored to produce iALD-MoS₂ thin films with a significantly increased grain size and surface coverage (>620%). Moreover, highly crystalline iALD-MoS₂ thin films, with thicknesses of only a few layers, excellent room temperature mobility (13.9 cm² V⁻¹ s⁻¹), and on/off ratios (>10⁸), employed as the channel material in field effect transistors on 6″ wafers, are successfully prepared.

High-mobility MoS₂ thin films with inhibitor-utilizing-atomic layer deposition (iALD) are successfully demonstrated in a wafer scale. As a reliable and rapid manufacturing process, MoS₂-iALD, based on the kinetics of Mo precursor adsorption, enables extraordinary grain growth and surface coverage, leading to an excellent room-temperature mobility (13.9 cm² V⁻¹ s⁻¹) and on/off ratios (>10⁸), as a channel material in a field effect transistor.

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