Wafer‐Scale Demonstration of Polycrystalline MoS2 Growth on 200 mm Glass and SiO2/Si Substrates by Plasma‐Enhanced Atomic Layer Deposition

Abstract

Abstract2D materials like transition metal dichalcogenides (TMDCs) have been widely studied and are a gateway to modern technologies. While research today is mostly carried out on a laboratory scale, there is an intensive need for reliable processes on a wafer‐scale, starting with monolayer‐precise deposition of high‐quality films. In this work, a plasma‐enhanced atomic layer deposition (PEALD) process is developed on a 200 mm SiO2/Si substrate. The layers are investigated regarding crystallinity, composition, homogeneity, microstructure, topography, and electrical properties. The process is then applied on 200 mm alkali‐free glass wafers aiming toward flexible electronics and compatibility with Si processes. A complete coverage of the wafer with a satisfying uniformity is achieved on both substrates and direct polycrystalline growth of MoS2 films is verified on the entire wafer at a substrate temperature of T = 230 °C. On glass, the deposited MoS2 films exhibit a higher crystallinity and are more planar compared to the SiO2/Si substrate. Furthermore, application relevant few‐nanometer thick layers are investigated in detail. This low‐temperature process inspires optimism for future direct integration of 2D‐materials in an economical bottom‐up approach on a wide variety of substrates, thus paving the way for industrial mass production.