Abstract

InAs/InAs1-xSbx type II superlattices designed for mid-wavelength infrared photo-detection have been studied using several electron microscopy methods, with specific attention directed towards interface chemical diffusion caused by Sb segregation. Reciprocal-space image analysis using the geometric phase method showed asymmetric interfacial strain profiles at the InAs-on-InAsSb interface. Measurement of local Sb compositional profiles across the superlattices using electron energy-loss spectroscopy and 002 dark-field imaging confirmed asymmetric Sb distribution, with the InAs-on-InAsSb interface being chemically graded. In contrast, the InAsSb-on-InAs interface showed a small intrinsic interface width. Careful evaluation of the experimental Sb composition profiles using a combined segregation and sigmoidal model reached quantitative agreement. Segregation dominated over the sigmoidal growth at the InAs-on-InAsSb interface, and the segregation probability of 0.81 ± 0.01 obtained from the two microscopy techniques agreed well within experimental error. Thus, 81% of Sb atoms from the topmost layers segregated into the next layer during growth causing the interfaces to be broadened over a length of ∼3 nm. This strong Sb segregation occurred throughout the whole superlattice stack, and would likely induce undesirable effects on band-gap engineering, such as blue-shift or broadening of the optical response, as well as weakened absorption.

Original languageEnglish (US)
Article number095702
JournalJournal of Applied Physics
Volume119
Issue number9
DOIs
StatePublished - Mar 7 2016

Fingerprint

antimony
superlattices
molecular beam epitaxy
evaluation
profiles
image analysis
blue shift
electron microscopy
interfacial tension
energy dissipation
engineering
electron energy
microscopy
wavelengths
spectroscopy
atoms

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Evaluation of antimony segregation in InAs/InAs1-xSbx type-II superlattices grown by molecular beam epitaxy. / Lu, Jing; Luna, Esperanza; Aoki, Toshihiro; Steenbergen, Elizabeth H.; Zhang, Yong-Hang; Smith, David.

In: Journal of Applied Physics, Vol. 119, No. 9, 095702, 07.03.2016.

Research output: Contribution to journalArticle

@article{1cfcec4b6d544477a5e0e108c0c7a3a3,
title = "Evaluation of antimony segregation in InAs/InAs1-xSbx type-II superlattices grown by molecular beam epitaxy",
abstract = "InAs/InAs1-xSbx type II superlattices designed for mid-wavelength infrared photo-detection have been studied using several electron microscopy methods, with specific attention directed towards interface chemical diffusion caused by Sb segregation. Reciprocal-space image analysis using the geometric phase method showed asymmetric interfacial strain profiles at the InAs-on-InAsSb interface. Measurement of local Sb compositional profiles across the superlattices using electron energy-loss spectroscopy and 002 dark-field imaging confirmed asymmetric Sb distribution, with the InAs-on-InAsSb interface being chemically graded. In contrast, the InAsSb-on-InAs interface showed a small intrinsic interface width. Careful evaluation of the experimental Sb composition profiles using a combined segregation and sigmoidal model reached quantitative agreement. Segregation dominated over the sigmoidal growth at the InAs-on-InAsSb interface, and the segregation probability of 0.81 ± 0.01 obtained from the two microscopy techniques agreed well within experimental error. Thus, 81{\%} of Sb atoms from the topmost layers segregated into the next layer during growth causing the interfaces to be broadened over a length of ∼3 nm. This strong Sb segregation occurred throughout the whole superlattice stack, and would likely induce undesirable effects on band-gap engineering, such as blue-shift or broadening of the optical response, as well as weakened absorption.",
author = "Jing Lu and Esperanza Luna and Toshihiro Aoki and Steenbergen, {Elizabeth H.} and Yong-Hang Zhang and David Smith",
year = "2016",
month = "3",
day = "7",
doi = "10.1063/1.4942844",
language = "English (US)",
volume = "119",
journal = "Journal of Applied Physics",
issn = "0021-8979",
publisher = "American Institute of Physics Publising LLC",
number = "9",

}

TY - JOUR

T1 - Evaluation of antimony segregation in InAs/InAs1-xSbx type-II superlattices grown by molecular beam epitaxy

AU - Lu, Jing

AU - Luna, Esperanza

AU - Aoki, Toshihiro

AU - Steenbergen, Elizabeth H.

AU - Zhang, Yong-Hang

AU - Smith, David

PY - 2016/3/7

Y1 - 2016/3/7

N2 - InAs/InAs1-xSbx type II superlattices designed for mid-wavelength infrared photo-detection have been studied using several electron microscopy methods, with specific attention directed towards interface chemical diffusion caused by Sb segregation. Reciprocal-space image analysis using the geometric phase method showed asymmetric interfacial strain profiles at the InAs-on-InAsSb interface. Measurement of local Sb compositional profiles across the superlattices using electron energy-loss spectroscopy and 002 dark-field imaging confirmed asymmetric Sb distribution, with the InAs-on-InAsSb interface being chemically graded. In contrast, the InAsSb-on-InAs interface showed a small intrinsic interface width. Careful evaluation of the experimental Sb composition profiles using a combined segregation and sigmoidal model reached quantitative agreement. Segregation dominated over the sigmoidal growth at the InAs-on-InAsSb interface, and the segregation probability of 0.81 ± 0.01 obtained from the two microscopy techniques agreed well within experimental error. Thus, 81% of Sb atoms from the topmost layers segregated into the next layer during growth causing the interfaces to be broadened over a length of ∼3 nm. This strong Sb segregation occurred throughout the whole superlattice stack, and would likely induce undesirable effects on band-gap engineering, such as blue-shift or broadening of the optical response, as well as weakened absorption.

AB - InAs/InAs1-xSbx type II superlattices designed for mid-wavelength infrared photo-detection have been studied using several electron microscopy methods, with specific attention directed towards interface chemical diffusion caused by Sb segregation. Reciprocal-space image analysis using the geometric phase method showed asymmetric interfacial strain profiles at the InAs-on-InAsSb interface. Measurement of local Sb compositional profiles across the superlattices using electron energy-loss spectroscopy and 002 dark-field imaging confirmed asymmetric Sb distribution, with the InAs-on-InAsSb interface being chemically graded. In contrast, the InAsSb-on-InAs interface showed a small intrinsic interface width. Careful evaluation of the experimental Sb composition profiles using a combined segregation and sigmoidal model reached quantitative agreement. Segregation dominated over the sigmoidal growth at the InAs-on-InAsSb interface, and the segregation probability of 0.81 ± 0.01 obtained from the two microscopy techniques agreed well within experimental error. Thus, 81% of Sb atoms from the topmost layers segregated into the next layer during growth causing the interfaces to be broadened over a length of ∼3 nm. This strong Sb segregation occurred throughout the whole superlattice stack, and would likely induce undesirable effects on band-gap engineering, such as blue-shift or broadening of the optical response, as well as weakened absorption.

UR - http://www.scopus.com/inward/record.url?scp=84959553560&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84959553560&partnerID=8YFLogxK

U2 - 10.1063/1.4942844

DO - 10.1063/1.4942844

M3 - Article

VL - 119

JO - Journal of Applied Physics

JF - Journal of Applied Physics

SN - 0021-8979

IS - 9

M1 - 095702

ER -