Nucleation and growth mechanisms of Al2O3 atomic layer deposition on synthetic polycrystalline MoS2

• DOI: 10.1063/1.4967406
• Publication Date: 2016-11-16T01:30:24Z
• Authors: H. Zhang; D. Chiappe; J. Meersschaut; T. Conard; A. Franquet; T. Nuytten; M. Mannarino; I. Radu; W. Vandervorst; A. Delabie
• Keywords: Elastic recoil detection; Deposition; Passivation

Two-dimensional (2D) semiconducting transition metal dichalcogenides (TMDs) are of great interest for applications in nano-electronic devices. Their incorporation requires the deposition nm-thin and continuous high-k dielectric layers on 2D TMDs. Atomic layer (ALD) is well established Si surfaces: importance a high nucleation density rapid closure known mechanisms have been thoroughly investigated. In contrast, ALD TMD surfaces less understood quantitative analysis process lacking. Therefore, this work, we investigate growth Al2O3 (using Al(CH3)3/H2O ALD) MoS2 whereby attempt to provide complete insight into use several complementary characterization techniques, including X-ray photo-electron spectroscopy, elastic recoil detection analysis, scanning electron microscopy, time-of-flight secondary ion mass spectrometry. To reveal inherent reactivity MoS2, exclude impact surface contamination from transfer by direct synthetic obtained temperature sulfurization process. It shown that strongly inhibited at temperatures between 125°C 300°C, with no occurring crystal basal planes selective only line defects or grain boundaries top surface. During further deposition, as-formed nano-ribbons grow both vertical lateral directions. Eventually, film over plane, point determined size rate. The created Al2O3/MoS2 interface consists mainly van der Waals interactions. improved contributions reversible adsorption using low combination short purge times. While results more two-dimensional growth, additional H C impurities incorporated layers. conclude, our study reveals plane extremely low, confirms need functionalization methods enable nucleation.