Change search
ReferencesLink to record
Permanent link

Direct link
Quantum Chemical Feasibility Study of Methylamines as Nitrogen Precursors in Chemical Vapor Deposition
Linköping University, Department of Physics, Chemistry and Biology, Chemistry.
2015 (English)Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
Abstract [en]

The possibility of using methylamines instead of ammonia as a nitrogen precursor for the CVD of nitrides is studied using quantum chemical computations of reaction energies: reaction electronic energy (Δ𝑟𝐸𝑒𝑙𝑒𝑐) reaction enthalpy (Δ𝑟𝐻) and reaction free energy (Δ𝑟𝐺). The reaction energies were calculated for three types of reactions: Uni- and bimolecular decomposition to more reactive nitrogen species, adduct forming with trimethylgallium (TMG) and trimethylaluminum (TMA) followed by a release of methane or ethane and surface adsorption to gallium nitride for both the unreacted ammonia or methylamines or the decomposition products. The calculations for the reaction entropy and free energy were made at both STP and CVD conditions (300°C-1300°C and 50 mbar). The ab inito Gaussian 4 (G4) theory were used for the calculations of the decomposition and adduct reactions while the surface adsorptions were calculated using the Density Functional Theory method B3LYP. From the reactions energies it can be concluded that the decomposition was facilitated by the increasing number of methyl groups on the nitrogen. The adducts with mono- and dimethylamine were more favorable than ammonia and trimethylamine. 𝑁𝐻2 was found to be most readily to adsorb to 𝐺𝑎𝑁 while the undecomposed ammonia and methylamines was not willingly to adsorb.

Place, publisher, year, edition, pages
2015. , 28 p.
Keyword [en]
Quantum Chemistry, Computational Chemistry, Density Functional Theory (DFT), B3LYP, Gaussian 4 (G4), Chemical Vapor Deposition (CVD), Gallium Nitride (GaN), Aluminum Nitride (AlN), Ammonia (NH3), Methylamine (NH2CH3), Dimethylamine (NH(CH3)2), Trimethylamine (NH(CH3)3), Trimethylaluminum (TMA), Trimethylgallium (TMG), Decomposition, Adsorption
National Category
Physical Chemistry
URN: urn:nbn:se:liu:diva-132812ISRN: LITH-IFM-G--EX--15/3046--SEOAI: diva2:1050500
Subject / course
Available from: 2016-11-29 Created: 2016-11-29 Last updated: 2016-11-29Bibliographically approved

Open Access in DiVA

fulltext(1543 kB)6 downloads
File information
File name FULLTEXT01.pdfFile size 1543 kBChecksum SHA-512
Type fulltextMimetype application/pdf

Search in DiVA

By author/editor
Rönnby, Karl
By organisation
Physical Chemistry

Search outside of DiVA

GoogleGoogle Scholar
Total: 6 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Total: 12 hits
ReferencesLink to record
Permanent link

Direct link