Croissance par épitaxie par jets moléculaires de films de nitrure d’aluminium sur substrats de silicium et de carbure de silicium étudiés par microscopie à force atomique en mode non contact et par microscopie à sonde de kelvin sous ultra vide

Florian Chaumeton 1
1 CEMES-GNS - Groupe NanoSciences
CEMES - Centre d'élaboration de matériaux et d'études structurales
Abstract : This thesis is part of molecular electronics, which aims to realize a calculation unit based on a single molecule connected to mesoscopic electrodes. The first step is to find a suitable surface, i.e. an insulating or large gap semi-conductor surface to decouple the electronic states of the molecule from the electronic states of the substrate. It must also be compatible with the growth of flat metallic nano-pads allowing the connection of the molecule to an electron tank, while having the possibility of imaging it in NC-AFM. Our choice was focused on the large gap semi-conductor Aluminum Nitride (AlN, 6.2 eV). Indeed it has been shown that the growth of magnesium on a similar substrate (GaN, 3.4 eV) yields one mono-layer high islands. The present work is focused on the growth by molecular beam epitaxy of AlN thin layers on silicon (Si(111)) and silicon carbide (SiC(0001)) substrates and in-situ study by NC-AFM and KPFM under ultrahigh vacuum. The NC-AFM studies helped to adapt the growth protocols in order to significantly reduce the surface defects of the AlN films. Theoretical calculations (DFT) helped to adapt these growth protocols which allows to reproducibly obtain the (2x2) surface reconstruction for which the surface is terminated by a layer of N atoms. At the end of this thesis, the AlN films obtained present suitable surfaces for depositing metallic electrodes and molecules.
Complete list of metadatas

Cited literature [125 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-01226410
Contributor : Florian Chaumeton <>
Submitted on : Monday, November 9, 2015 - 2:55:50 PM
Last modification on : Monday, April 29, 2019 - 5:19:31 PM
Long-term archiving on : Wednesday, February 10, 2016 - 10:28:49 AM

Identifiers

  • HAL Id : tel-01226410, version 1

Citation

Florian Chaumeton. Croissance par épitaxie par jets moléculaires de films de nitrure d’aluminium sur substrats de silicium et de carbure de silicium étudiés par microscopie à force atomique en mode non contact et par microscopie à sonde de kelvin sous ultra vide. Science des matériaux [cond-mat.mtrl-sci]. université Paul Sabatier Toulouse III, 2015. Français. ⟨tel-01226410⟩

Share

Metrics

Record views

268

Files downloads

154