Modification of dislocation behavior in GaN overgrown on engineered AlN film-on-bulk Si substrate

Mihir Tungare, Xiaojun Weng, Jeffrey M. Leathersich, Puneet Suvarna, Joan Marie Redwing, F. Shahedipour-Sandvik

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

The changes that the AlN buffer and Si substrate undergo at each stage of our substrate engineering process, previously shown to lead to a simultaneous and substantial reduction in film crack density and dislocation density in overgrown GaN, are presented. Evidence of ion-implantation assisted grain reorientation for AlN islands coupled with physical isolation from the bulk Si substrate prove to be the dominating driving forces. This is further emphasized with x-ray diffraction analysis that demonstrates a reduction in the in-plane lattice constant of AlN from 3.148 Å to 3.113 Å and a relative change in rotation of AlN islands by 0.135° with regard to the Si substrate after substrate engineering. Misfit dislocations at the AlN-Si interface and disorder that is normally associated with formation of amorphous SiNx at this interface are considered to be two of the major contributors to dislocation nucleation within overgrown GaN. Following our technique, the disappearance of disorder at the AlN-Si interface is observed. Extensive ellipsometry and transmission electron microscopy suggests that larger AlN islands with a smoother surface morphology could further reduce the dislocation density below that previously reported. A 1.2 μm GaN layer deposited on an AlN buffer with larger islands and smoother morphology exhibits a 14× reduction in surface pit density after undergoing the ion-implantation assisted substrate modification technique.

Original languageEnglish (US)
Article number163108
JournalJournal of Applied Physics
Volume113
Issue number16
DOIs
StatePublished - Apr 28 2013

Fingerprint

ion implantation
buffers
engineering
disorders
retraining
ellipsometry
isolation
x ray diffraction
cracks
nucleation
transmission electron microscopy

All Science Journal Classification (ASJC) codes

  • Physics and Astronomy(all)

Cite this

Tungare, Mihir ; Weng, Xiaojun ; Leathersich, Jeffrey M. ; Suvarna, Puneet ; Redwing, Joan Marie ; Shahedipour-Sandvik, F. / Modification of dislocation behavior in GaN overgrown on engineered AlN film-on-bulk Si substrate. In: Journal of Applied Physics. 2013 ; Vol. 113, No. 16.
@article{89e5152b8eff4e16ac494f61fec42534,
title = "Modification of dislocation behavior in GaN overgrown on engineered AlN film-on-bulk Si substrate",
abstract = "The changes that the AlN buffer and Si substrate undergo at each stage of our substrate engineering process, previously shown to lead to a simultaneous and substantial reduction in film crack density and dislocation density in overgrown GaN, are presented. Evidence of ion-implantation assisted grain reorientation for AlN islands coupled with physical isolation from the bulk Si substrate prove to be the dominating driving forces. This is further emphasized with x-ray diffraction analysis that demonstrates a reduction in the in-plane lattice constant of AlN from 3.148 {\AA} to 3.113 {\AA} and a relative change in rotation of AlN islands by 0.135° with regard to the Si substrate after substrate engineering. Misfit dislocations at the AlN-Si interface and disorder that is normally associated with formation of amorphous SiNx at this interface are considered to be two of the major contributors to dislocation nucleation within overgrown GaN. Following our technique, the disappearance of disorder at the AlN-Si interface is observed. Extensive ellipsometry and transmission electron microscopy suggests that larger AlN islands with a smoother surface morphology could further reduce the dislocation density below that previously reported. A 1.2 μm GaN layer deposited on an AlN buffer with larger islands and smoother morphology exhibits a 14× reduction in surface pit density after undergoing the ion-implantation assisted substrate modification technique.",
author = "Mihir Tungare and Xiaojun Weng and Leathersich, {Jeffrey M.} and Puneet Suvarna and Redwing, {Joan Marie} and F. Shahedipour-Sandvik",
year = "2013",
month = "4",
day = "28",
doi = "10.1063/1.4798598",
language = "English (US)",
volume = "113",
journal = "Journal of Applied Physics",
issn = "0021-8979",
publisher = "American Institute of Physics Publising LLC",
number = "16",

}

Modification of dislocation behavior in GaN overgrown on engineered AlN film-on-bulk Si substrate. / Tungare, Mihir; Weng, Xiaojun; Leathersich, Jeffrey M.; Suvarna, Puneet; Redwing, Joan Marie; Shahedipour-Sandvik, F.

In: Journal of Applied Physics, Vol. 113, No. 16, 163108, 28.04.2013.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Modification of dislocation behavior in GaN overgrown on engineered AlN film-on-bulk Si substrate

AU - Tungare, Mihir

AU - Weng, Xiaojun

AU - Leathersich, Jeffrey M.

AU - Suvarna, Puneet

AU - Redwing, Joan Marie

AU - Shahedipour-Sandvik, F.

PY - 2013/4/28

Y1 - 2013/4/28

N2 - The changes that the AlN buffer and Si substrate undergo at each stage of our substrate engineering process, previously shown to lead to a simultaneous and substantial reduction in film crack density and dislocation density in overgrown GaN, are presented. Evidence of ion-implantation assisted grain reorientation for AlN islands coupled with physical isolation from the bulk Si substrate prove to be the dominating driving forces. This is further emphasized with x-ray diffraction analysis that demonstrates a reduction in the in-plane lattice constant of AlN from 3.148 Å to 3.113 Å and a relative change in rotation of AlN islands by 0.135° with regard to the Si substrate after substrate engineering. Misfit dislocations at the AlN-Si interface and disorder that is normally associated with formation of amorphous SiNx at this interface are considered to be two of the major contributors to dislocation nucleation within overgrown GaN. Following our technique, the disappearance of disorder at the AlN-Si interface is observed. Extensive ellipsometry and transmission electron microscopy suggests that larger AlN islands with a smoother surface morphology could further reduce the dislocation density below that previously reported. A 1.2 μm GaN layer deposited on an AlN buffer with larger islands and smoother morphology exhibits a 14× reduction in surface pit density after undergoing the ion-implantation assisted substrate modification technique.

AB - The changes that the AlN buffer and Si substrate undergo at each stage of our substrate engineering process, previously shown to lead to a simultaneous and substantial reduction in film crack density and dislocation density in overgrown GaN, are presented. Evidence of ion-implantation assisted grain reorientation for AlN islands coupled with physical isolation from the bulk Si substrate prove to be the dominating driving forces. This is further emphasized with x-ray diffraction analysis that demonstrates a reduction in the in-plane lattice constant of AlN from 3.148 Å to 3.113 Å and a relative change in rotation of AlN islands by 0.135° with regard to the Si substrate after substrate engineering. Misfit dislocations at the AlN-Si interface and disorder that is normally associated with formation of amorphous SiNx at this interface are considered to be two of the major contributors to dislocation nucleation within overgrown GaN. Following our technique, the disappearance of disorder at the AlN-Si interface is observed. Extensive ellipsometry and transmission electron microscopy suggests that larger AlN islands with a smoother surface morphology could further reduce the dislocation density below that previously reported. A 1.2 μm GaN layer deposited on an AlN buffer with larger islands and smoother morphology exhibits a 14× reduction in surface pit density after undergoing the ion-implantation assisted substrate modification technique.

UR - http://www.scopus.com/inward/record.url?scp=84877245247&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84877245247&partnerID=8YFLogxK

U2 - 10.1063/1.4798598

DO - 10.1063/1.4798598

M3 - Article

AN - SCOPUS:84877245247

VL - 113

JO - Journal of Applied Physics

JF - Journal of Applied Physics

SN - 0021-8979

IS - 16

M1 - 163108

ER -