Oxidation of GaN

An ab initio thermodynamic approach

Adam Jackson, A Walsh

Research output: Contribution to journalArticle

11 Citations (Scopus)
44 Downloads (Pure)

Abstract

GaN is a wide-band-gap semiconductor used in high-efficiency light-emitting diodes and solar cells. The solid is produced industrially at high chemical purities by deposition from a vapor phase, and oxygen may be included at this stage. Oxidation represents a potential path for tuning its properties without introducing more exotic elements or extreme processing conditions. In this work, ab initio computational methods are used to examine the energy potentials and electronic properties of different extents of oxidation in GaN. Solid-state vibrational properties of Ga, GaN, Ga2O3, and a single substitutional oxygen defect have been studied using the harmonic approximation with supercells. A thermodynamic model is outlined which combines the results of ab initio calculations with data from experimental literature. This model allows free energies to be predicted for arbitrary reaction conditions within a wide process envelope. It is shown that complete oxidation is favorable for all industrially relevant conditions, while the formation of defects can be opposed by the use of high temperatures and a high N2:O2 ratio.

Original languageEnglish
Article number165201
Number of pages10
JournalPhysical Review B
Volume88
Issue number16
Early online date11 Oct 2013
DOIs
Publication statusPublished - 2013

Fingerprint

Thermodynamics
Oxidation
thermodynamics
oxidation
Oxygen
Defects
defects
oxygen
Computational methods
Potential energy
Electronic properties
Free energy
Light emitting diodes
Solar cells
purity
envelopes
light emitting diodes
Tuning
solar cells
potential energy

Keywords

  • GaN
  • gallium nitride
  • ab initio calculations
  • density functional theory
  • thermodynamics
  • modelling

Cite this

Oxidation of GaN : An ab initio thermodynamic approach. / Jackson, Adam; Walsh, A.

In: Physical Review B, Vol. 88, No. 16, 165201, 2013.

Research output: Contribution to journalArticle

Jackson, Adam ; Walsh, A. / Oxidation of GaN : An ab initio thermodynamic approach. In: Physical Review B. 2013 ; Vol. 88, No. 16.
@article{d704af9da20f41239120bf3115f58e55,
title = "Oxidation of GaN: An ab initio thermodynamic approach",
abstract = "GaN is a wide-band-gap semiconductor used in high-efficiency light-emitting diodes and solar cells. The solid is produced industrially at high chemical purities by deposition from a vapor phase, and oxygen may be included at this stage. Oxidation represents a potential path for tuning its properties without introducing more exotic elements or extreme processing conditions. In this work, ab initio computational methods are used to examine the energy potentials and electronic properties of different extents of oxidation in GaN. Solid-state vibrational properties of Ga, GaN, Ga2O3, and a single substitutional oxygen defect have been studied using the harmonic approximation with supercells. A thermodynamic model is outlined which combines the results of ab initio calculations with data from experimental literature. This model allows free energies to be predicted for arbitrary reaction conditions within a wide process envelope. It is shown that complete oxidation is favorable for all industrially relevant conditions, while the formation of defects can be opposed by the use of high temperatures and a high N2:O2 ratio.",
keywords = "GaN, gallium nitride, ab initio calculations, density functional theory, thermodynamics, modelling",
author = "Adam Jackson and A Walsh",
year = "2013",
doi = "10.1103/PhysRevB.88.165201",
language = "English",
volume = "88",
journal = "Physical Review B : Condensed Matter and Materials Physics",
issn = "1098-0121",
publisher = "American Physical Society",
number = "16",

}

TY - JOUR

T1 - Oxidation of GaN

T2 - An ab initio thermodynamic approach

AU - Jackson, Adam

AU - Walsh, A

PY - 2013

Y1 - 2013

N2 - GaN is a wide-band-gap semiconductor used in high-efficiency light-emitting diodes and solar cells. The solid is produced industrially at high chemical purities by deposition from a vapor phase, and oxygen may be included at this stage. Oxidation represents a potential path for tuning its properties without introducing more exotic elements or extreme processing conditions. In this work, ab initio computational methods are used to examine the energy potentials and electronic properties of different extents of oxidation in GaN. Solid-state vibrational properties of Ga, GaN, Ga2O3, and a single substitutional oxygen defect have been studied using the harmonic approximation with supercells. A thermodynamic model is outlined which combines the results of ab initio calculations with data from experimental literature. This model allows free energies to be predicted for arbitrary reaction conditions within a wide process envelope. It is shown that complete oxidation is favorable for all industrially relevant conditions, while the formation of defects can be opposed by the use of high temperatures and a high N2:O2 ratio.

AB - GaN is a wide-band-gap semiconductor used in high-efficiency light-emitting diodes and solar cells. The solid is produced industrially at high chemical purities by deposition from a vapor phase, and oxygen may be included at this stage. Oxidation represents a potential path for tuning its properties without introducing more exotic elements or extreme processing conditions. In this work, ab initio computational methods are used to examine the energy potentials and electronic properties of different extents of oxidation in GaN. Solid-state vibrational properties of Ga, GaN, Ga2O3, and a single substitutional oxygen defect have been studied using the harmonic approximation with supercells. A thermodynamic model is outlined which combines the results of ab initio calculations with data from experimental literature. This model allows free energies to be predicted for arbitrary reaction conditions within a wide process envelope. It is shown that complete oxidation is favorable for all industrially relevant conditions, while the formation of defects can be opposed by the use of high temperatures and a high N2:O2 ratio.

KW - GaN

KW - gallium nitride

KW - ab initio calculations

KW - density functional theory

KW - thermodynamics

KW - modelling

UR - http://www.scopus.com/inward/record.url?scp=84885705458&partnerID=8YFLogxK

UR - http://dx.doi.org/10.1103/PhysRevB.88.165201

U2 - 10.1103/PhysRevB.88.165201

DO - 10.1103/PhysRevB.88.165201

M3 - Article

VL - 88

JO - Physical Review B : Condensed Matter and Materials Physics

JF - Physical Review B : Condensed Matter and Materials Physics

SN - 1098-0121

IS - 16

M1 - 165201

ER -