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Title: ZnSe interlayer effects on properties of (CdS/ZnSe)/BeTe superlattices grown by molecular beam epitaxy

Abstract

We study the dependence of structural properties on the thickness of the ZnSe interlayer (IL) in (CdS/ZnSe)/BeTe superlattices (SLs); this is crucial for improving the growth mode in this heterostructure. The in situ reflection of high-energy electron diffraction oscillation and high-resolution x-ray diffraction spectra show a perfect structure that is obtained by introducing a ZnSe IL between CdS and BeTe. An intersubband transition (ISB-T) down to 1.57 {mu}m with a full width at half maximum of 90 meV has been observed in (CdS/ZnSe)/BeTe SLs. A strong ISB-T is observed when the ZnSe IL {>=}1 monolayer (ML); however, it completely disappears with the introduction of a 0.5 ML ZnSe IL in (CdS/ZnSe)/BeTe SLs. High-resolution transmission electron microscopy images reveal that a sharp interface is formed in the barrier and well transition region in the structure with ZnSe IL {>=}1 ML; however, the interfaces become rough and thick in those with a 0.5 ML ZnSe IL. This indicates that the properties of the interface in (CdS/ZnSe)/BeTe SLs play an important role in the performance of ISB absorption. A growth model is proposed to explain two-dimensional growth with the insertion of a ZnSe ML into the BeTe/CdS heterostructure. Based on this growth model,more » the properties of the interface in this structure are explained.« less

Authors:
; ; ;  [1]
  1. Ultrafast Photonic Devices Laboratory, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan)
Publication Date:
OSTI Identifier:
20787889
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 99; Journal Issue: 4; Other Information: DOI: 10.1063/1.2173686; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ABSORPTION; BERYLLIUM ALLOYS; BERYLLIUM TELLURIDES; CADMIUM SULFIDES; CRYSTAL GROWTH; ELECTRON DIFFRACTION; MILLI EV RANGE; MOLECULAR BEAM EPITAXY; QUANTUM WELLS; RESOLUTION; SEMICONDUCTOR MATERIALS; SUPERLATTICES; TELLURIUM ALLOYS; TRANSMISSION ELECTRON MICROSCOPY; X-RAY DIFFRACTION; ZINC SELENIDES

Citation Formats

Li, B.S., Akimoto, R., Akita, K., and Hasama, T. ZnSe interlayer effects on properties of (CdS/ZnSe)/BeTe superlattices grown by molecular beam epitaxy. United States: N. p., 2006. Web. doi:10.1063/1.2173686.
Li, B.S., Akimoto, R., Akita, K., & Hasama, T. ZnSe interlayer effects on properties of (CdS/ZnSe)/BeTe superlattices grown by molecular beam epitaxy. United States. doi:10.1063/1.2173686.
Li, B.S., Akimoto, R., Akita, K., and Hasama, T. Wed . "ZnSe interlayer effects on properties of (CdS/ZnSe)/BeTe superlattices grown by molecular beam epitaxy". United States. doi:10.1063/1.2173686.
@article{osti_20787889,
title = {ZnSe interlayer effects on properties of (CdS/ZnSe)/BeTe superlattices grown by molecular beam epitaxy},
author = {Li, B.S. and Akimoto, R. and Akita, K. and Hasama, T.},
abstractNote = {We study the dependence of structural properties on the thickness of the ZnSe interlayer (IL) in (CdS/ZnSe)/BeTe superlattices (SLs); this is crucial for improving the growth mode in this heterostructure. The in situ reflection of high-energy electron diffraction oscillation and high-resolution x-ray diffraction spectra show a perfect structure that is obtained by introducing a ZnSe IL between CdS and BeTe. An intersubband transition (ISB-T) down to 1.57 {mu}m with a full width at half maximum of 90 meV has been observed in (CdS/ZnSe)/BeTe SLs. A strong ISB-T is observed when the ZnSe IL {>=}1 monolayer (ML); however, it completely disappears with the introduction of a 0.5 ML ZnSe IL in (CdS/ZnSe)/BeTe SLs. High-resolution transmission electron microscopy images reveal that a sharp interface is formed in the barrier and well transition region in the structure with ZnSe IL {>=}1 ML; however, the interfaces become rough and thick in those with a 0.5 ML ZnSe IL. This indicates that the properties of the interface in (CdS/ZnSe)/BeTe SLs play an important role in the performance of ISB absorption. A growth model is proposed to explain two-dimensional growth with the insertion of a ZnSe ML into the BeTe/CdS heterostructure. Based on this growth model, the properties of the interface in this structure are explained.},
doi = {10.1063/1.2173686},
journal = {Journal of Applied Physics},
number = 4,
volume = 99,
place = {United States},
year = {Wed Feb 15 00:00:00 EST 2006},
month = {Wed Feb 15 00:00:00 EST 2006}
}
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