Strain and compositional analysis of InGaN/GaN layers

Sérgio Pereira, Maria R. Correia, Estela Pereira, C. Trager-Cowan, F. Sweeney, P. R. Edwards, K. P. O'Donnell, E. Alves, A. D. Sequeira, N. Franco

Research output: Contribution to journalArticle

Abstract

We investigate strain and composition of epitaxial single layers of wurtzite InxGa1-xN (0<x<0.25) grown by MOCVD on top of GaN/Al2O3 substrates. It is shown that significant inaccuracies may arise in composition assessments if strain in InxGa1-xN/GaN heterostructures is not properly taken into account. Rutherford backscattering spectrometry (RBS) measures composition, free from the effects of strain and with depth resolution. Using X-ray diffraction (XRD) we measure both a- and c- parameters of the strained wurtzite films. By measuring both lattice parameters and solving Hooke's equation, a good estimation for composition can be obtained from XRD data. The agreement between RBS and XRD data for composition allows reliable values for perpendicular (εzz) and parallel strain components (εxx) to be determined. RBS and depth resolved cathodoluminescence (CL) measurements further indicate that the indium content is not uniform over depth in some samples. This effect occurs for the most strained layers, suggesting that strain is the driving force for compositional pulling.

LanguageEnglish
PagesG3.52.1-G3.52.6
JournalMaterials Research Society Symposium - Proceedings
Volume639
DOIs
Publication statusPublished - 1 Jan 2001

Fingerprint

Rutherford backscattering spectroscopy
Spectrometry
Chemical analysis
backscattering
X ray diffraction
wurtzite
diffraction
spectroscopy
Indium
x rays
Cathodoluminescence
pulling
Metallorganic chemical vapor deposition
cathodoluminescence
Lattice constants
metalorganic chemical vapor deposition
indium
Heterojunctions
lattice parameters
Substrates

Keywords

  • InGaN/GaN layers
  • wurtzite InGaN/GaN layers
  • wurtzite
  • cathodoluminescence

Cite this

Pereira, Sérgio ; Correia, Maria R. ; Pereira, Estela ; Trager-Cowan, C. ; Sweeney, F. ; Edwards, P. R. ; O'Donnell, K. P. ; Alves, E. ; Sequeira, A. D. ; Franco, N. / Strain and compositional analysis of InGaN/GaN layers. In: Materials Research Society Symposium - Proceedings. 2001 ; Vol. 639. pp. G3.52.1-G3.52.6.
@article{9c72618444df44f6956a82f9a6e322d4,
title = "Strain and compositional analysis of InGaN/GaN layers",
abstract = "We investigate strain and composition of epitaxial single layers of wurtzite InxGa1-xN (02O3 substrates. It is shown that significant inaccuracies may arise in composition assessments if strain in InxGa1-xN/GaN heterostructures is not properly taken into account. Rutherford backscattering spectrometry (RBS) measures composition, free from the effects of strain and with depth resolution. Using X-ray diffraction (XRD) we measure both a- and c- parameters of the strained wurtzite films. By measuring both lattice parameters and solving Hooke's equation, a good estimation for composition can be obtained from XRD data. The agreement between RBS and XRD data for composition allows reliable values for perpendicular (εzz) and parallel strain components (εxx) to be determined. RBS and depth resolved cathodoluminescence (CL) measurements further indicate that the indium content is not uniform over depth in some samples. This effect occurs for the most strained layers, suggesting that strain is the driving force for compositional pulling.",
keywords = "InGaN/GaN layers, wurtzite InGaN/GaN layers, wurtzite, cathodoluminescence",
author = "S{\'e}rgio Pereira and Correia, {Maria R.} and Estela Pereira and C. Trager-Cowan and F. Sweeney and Edwards, {P. R.} and O'Donnell, {K. P.} and E. Alves and Sequeira, {A. D.} and N. Franco",
year = "2001",
month = "1",
day = "1",
doi = "10.1557/PROC-639-G3.52",
language = "English",
volume = "639",
pages = "G3.52.1--G3.52.6",
journal = "MRS Online Proceedings Library",
issn = "1946-4274",

}

Pereira, S, Correia, MR, Pereira, E, Trager-Cowan, C, Sweeney, F, Edwards, PR, O'Donnell, KP, Alves, E, Sequeira, AD & Franco, N 2001, 'Strain and compositional analysis of InGaN/GaN layers' Materials Research Society Symposium - Proceedings, vol. 639, pp. G3.52.1-G3.52.6. https://doi.org/10.1557/PROC-639-G3.52

Strain and compositional analysis of InGaN/GaN layers. / Pereira, Sérgio; Correia, Maria R.; Pereira, Estela; Trager-Cowan, C.; Sweeney, F.; Edwards, P. R.; O'Donnell, K. P.; Alves, E.; Sequeira, A. D.; Franco, N.

In: Materials Research Society Symposium - Proceedings, Vol. 639, 01.01.2001, p. G3.52.1-G3.52.6.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Strain and compositional analysis of InGaN/GaN layers

AU - Pereira, Sérgio

AU - Correia, Maria R.

AU - Pereira, Estela

AU - Trager-Cowan, C.

AU - Sweeney, F.

AU - Edwards, P. R.

AU - O'Donnell, K. P.

AU - Alves, E.

AU - Sequeira, A. D.

AU - Franco, N.

PY - 2001/1/1

Y1 - 2001/1/1

N2 - We investigate strain and composition of epitaxial single layers of wurtzite InxGa1-xN (02O3 substrates. It is shown that significant inaccuracies may arise in composition assessments if strain in InxGa1-xN/GaN heterostructures is not properly taken into account. Rutherford backscattering spectrometry (RBS) measures composition, free from the effects of strain and with depth resolution. Using X-ray diffraction (XRD) we measure both a- and c- parameters of the strained wurtzite films. By measuring both lattice parameters and solving Hooke's equation, a good estimation for composition can be obtained from XRD data. The agreement between RBS and XRD data for composition allows reliable values for perpendicular (εzz) and parallel strain components (εxx) to be determined. RBS and depth resolved cathodoluminescence (CL) measurements further indicate that the indium content is not uniform over depth in some samples. This effect occurs for the most strained layers, suggesting that strain is the driving force for compositional pulling.

AB - We investigate strain and composition of epitaxial single layers of wurtzite InxGa1-xN (02O3 substrates. It is shown that significant inaccuracies may arise in composition assessments if strain in InxGa1-xN/GaN heterostructures is not properly taken into account. Rutherford backscattering spectrometry (RBS) measures composition, free from the effects of strain and with depth resolution. Using X-ray diffraction (XRD) we measure both a- and c- parameters of the strained wurtzite films. By measuring both lattice parameters and solving Hooke's equation, a good estimation for composition can be obtained from XRD data. The agreement between RBS and XRD data for composition allows reliable values for perpendicular (εzz) and parallel strain components (εxx) to be determined. RBS and depth resolved cathodoluminescence (CL) measurements further indicate that the indium content is not uniform over depth in some samples. This effect occurs for the most strained layers, suggesting that strain is the driving force for compositional pulling.

KW - InGaN/GaN layers

KW - wurtzite InGaN/GaN layers

KW - wurtzite

KW - cathodoluminescence

UR - http://www.scopus.com/inward/record.url?scp=85009874498&partnerID=8YFLogxK

U2 - 10.1557/PROC-639-G3.52

DO - 10.1557/PROC-639-G3.52

M3 - Article

VL - 639

SP - G3.52.1-G3.52.6

JO - MRS Online Proceedings Library

T2 - MRS Online Proceedings Library

JF - MRS Online Proceedings Library

SN - 1946-4274

ER -