First principles study of the atomic layer deposition of alumina by TMA-H2O-process

 |  Login

Show simple item record

dc.contributor Aalto-yliopisto fi
dc.contributor Aalto University en
dc.contributor.author Weckman, Timo
dc.contributor.author Laasonen, Kari fi
dc.date.accessioned 2016-07-27T09:01:13Z
dc.date.available 2016-07-27T09:01:13Z
dc.date.issued 2015
dc.identifier.citation Weckman, Timo & Laasonen, Kari. 2015. First principles study of the atomic layer deposition of alumina by TMA-H2O-process. Physical Chemistry Chemical Physics. Issue 17. 17322-17334. DOI: 10.1039/C5CP01912E. en
dc.identifier.uri https://aaltodoc.aalto.fi/handle/123456789/21229
dc.description.abstract Atomic layer deposition (ALD) is a coating technology used to produce highly uniform thin films. Aluminiumoxide, Al2O3, is mainly deposited using trimethylaluminium (TMA) and water as precursors and is the most studied ALD-process to date. However, only few theoretical studies have been reported in the literature. The surface reaction mechanisms and energetics previously reported focus on a gibbsite-like surface model but a more realistic description of the surface can be achieved when the hydroxylation of the surface is taken into account using dissociatively adsorbed water molecules. The adsorbed water changes the structure of the surface and reaction energetics change considerably when compared to previously studied surface model. Here we have studied the TMA/H2O process using density functional theory on a hydroxylated alumina surface and reproduced the previous results for comparison. Mechanisms and energetics during both the TMA and the subsequent water pulse are presented. TMA is found to adsorb exothermically onto the surface. The reaction barriers for the ligand-exchange reactions between the TMA and the surface hydroxyl groups were found to be much lower compared to previously presented results. TMA dissociation on the surface is predicted to saturate at monomethylaluminium. Barriers for proton diffusion between surface sites are observed to be low. TMA adsorption was also found to be cooperative with the formation of methyl bridges between the adsorbants. The water pulse was studied using single water molecules reacting with the DMA and MMA surface species. Barriers for these reactions were found to reasonable in the process conditions. However, stabilizing interactions amongst water molecules were found to lower the reaction barriers and the dynamical nature of water is predicted to be of importance. It is expected that these calculations can only set an upper limit for the barriers during the water pulse. en
dc.format.extent 17322-17334
dc.format.mimetype application/pdf en
dc.language.iso en en
dc.publisher Royal Society of Chemistry en
dc.relation info:eu-repo/grantAgreement/Suomen Akatemia/COMP/9158041; Suomen Akatemia/Nanoclusters/13140115; Suomen Akatemia/Optical/13258547
dc.relation.ispartofseries Physical Chemistry Chemical Physics en
dc.relation.ispartofseries Issue 17
dc.rights © 2015 Royal Society of Chemistry. This is the post print version of the following article: Weckman, Timo & Laasonen, Kari. 2015. First principles study of the atomic layer deposition of alumina by TMA-H2O-process. Physical Chemistry Chemical Physics. Issue 17. 17322-17334. DOI: 10.1039/C5CP01912E, which has been published in final form at http://pubs.rsc.org/en/Content/ArticleLanding/2015/CP/C5CP01912E#!divAbstract. en
dc.subject.other Chemistry en
dc.subject.other Physics en
dc.title First principles study of the atomic layer deposition of alumina by TMA-H2O-process en
dc.type A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä fi
dc.description.version Peer reviewed en
dc.rights.holder Royal Society of Chemistry
dc.contributor.school Kemian tekniikan korkeakoulu fi
dc.contributor.school School of Chemical Technology en
dc.contributor.department Kemian laitos fi
dc.contributor.department Department of Chemistry en
dc.subject.keyword dft en
dc.subject.keyword ald en
dc.subject.keyword density functional theory en
dc.subject.keyword atomic layer deposition en
dc.subject.keyword alumina en
dc.identifier.urn URN:NBN:fi:aalto-201512215842
dc.type.dcmitype text en
dc.identifier.doi 10.1039/C5CP01912E
dc.contributor.lab Research Group of Computational Chemistry en
dc.contributor.lab Laskennallisen kemian tutkimusryhmä fi
dc.type.version Post print en


Files in this item

This item appears in the following Collection(s)

Show simple item record

Search archive


Advanced Search

article-iconSubmit a publication

Browse

My Account