Surface chemistry in atomic layer deposition of AlN thin films from Al(CH3)3 and NH3 studied by mass spectrometry
Preprint
- 9 May 2024
- preprint
- Published by American Chemical Society (ACS) in ChemRxiv
Abstract
Aluminum nitride (AlN) is a semiconductor with a very wide band gap and a potential dielectric material. Deposition of thin AlN films is routinely done by several techniques, including atomic layer deposition (ALD). In this study, we deposited AlN using ALD with trimethylaluminum (TMA) as the Al precursor and ammonia (NH3) with and without plasma activation as the N precursor in the temperature range from 100 to 400 °C while monitoring the surface reactions using mass spectrometry. Our results, combined with recent quantum chemical modelling, suggest that the surface chemistry of the deposition process is chemisorption of TMA followed by reductive elimination of the methyl groups to render mono methyl aluminum species. The NH3 chemisorption is done by ligand exchange to form CH4 and an -NH2 terminated surface.Keywords
All Related Versions
- Version 1, 2024-05-09, ChemRxiv
- Published version: Journal of Materials Chemistry C, 12 (33), 12818.
This publication has 13 references indexed in Scilit:
- Surface chemical mechanisms of trimethyl aluminum in atomic layer deposition of AlNJournal of Materials Chemistry C, 2023
- Surface Structures from NH3 Chemisorption in CVD and ALD of AlN, GaN, and InN FilmsThe Journal of Physical Chemistry C, 2022
- Reduction of Carbon Impurities in Aluminum Nitride from Time-Resolved Chemical Vapor Deposition Using TrimethylaluminumThe Journal of Physical Chemistry C, 2020
- Strategies for avoiding saturation effects in ESI-MSInternational Journal of Mass Spectrometry, 2020
- AlN grown on Si(1 1 1) by ammonia-molecular beam epitaxy in the 900–1200 °C temperature rangeJournal of Crystal Growth, 2017
- Electrical and Corrosion Properties of Titanium Aluminum Nitride Thin Films Prepared by Plasma-Enhanced Atomic Layer DepositionJournal of Materials Science & Technology, 2017
- Properties of AlN grown by plasma enhanced atomic layer depositionApplied Surface Science, 2011
- Synthesis, Characterization, and Reaction of Aluminum Halide Amides Supported by a Bulky β-Diketiminato LigandInorganic Chemistry, 2008
- Growth of Aluminum Nitride on Porous Alumina and Silica through Separate Saturated Gas−Solid Reactions of Trimethylaluminum and AmmoniaChemistry of Materials, 2002
- Low temperature deposition of AIN films by an alternate supply of trimethyl aluminum and ammoniaChemical Vapor Deposition, 1996