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Title: Structure and optical band gaps of (Ba,Sr)SnO{sub 3} films grown by molecular beam epitaxy

Abstract

Epitaxial growth of (Ba{sub x}Sr{sub 1−x})SnO{sub 3} films with 0 ≤ x ≤ 1 using molecular beam epitaxy is reported. It is shown that SrSnO{sub 3} films can be grown coherently strained on closely lattice and symmetry matched PrScO{sub 3} substrates. The evolution of the optical band gap as a function of composition is determined by spectroscopic ellipsometry. The direct band gap monotonously decreases with x from to 4.46 eV (x = 0) to 3.36 eV (x = 1). A large Burnstein-Moss shift is observed with La-doping of BaSnO{sub 3} films. The shift corresponds approximately to the increase in Fermi level and is consistent with the low conduction band mass.

Authors:
; ; ; ;  [1]
  1. Materials Department, University of California, Santa Barbara, California 93106-5050 (United States)
Publication Date:
OSTI Identifier:
22592855
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films; Journal Volume: 34; Journal Issue: 5; Other Information: (c) 2016 American Vacuum Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; APPROXIMATIONS; BARIUM COMPOUNDS; ELLIPSOMETRY; FERMI LEVEL; FILMS; MOLECULAR BEAM EPITAXY; MOLECULAR BEAMS; MOSSES; STRAINS; STRONTIUM COMPOUNDS; SUBSTRATES; SYMMETRY; TIN OXIDES

Citation Formats

Schumann, Timo, Raghavan, Santosh, Ahadi, Kaveh, Kim, Honggyu, and Stemmer, Susanne, E-mail: stemmer@mrl.ucsb.edu. Structure and optical band gaps of (Ba,Sr)SnO{sub 3} films grown by molecular beam epitaxy. United States: N. p., 2016. Web. doi:10.1116/1.4959004.
Schumann, Timo, Raghavan, Santosh, Ahadi, Kaveh, Kim, Honggyu, & Stemmer, Susanne, E-mail: stemmer@mrl.ucsb.edu. Structure and optical band gaps of (Ba,Sr)SnO{sub 3} films grown by molecular beam epitaxy. United States. doi:10.1116/1.4959004.
Schumann, Timo, Raghavan, Santosh, Ahadi, Kaveh, Kim, Honggyu, and Stemmer, Susanne, E-mail: stemmer@mrl.ucsb.edu. 2016. "Structure and optical band gaps of (Ba,Sr)SnO{sub 3} films grown by molecular beam epitaxy". United States. doi:10.1116/1.4959004.
@article{osti_22592855,
title = {Structure and optical band gaps of (Ba,Sr)SnO{sub 3} films grown by molecular beam epitaxy},
author = {Schumann, Timo and Raghavan, Santosh and Ahadi, Kaveh and Kim, Honggyu and Stemmer, Susanne, E-mail: stemmer@mrl.ucsb.edu},
abstractNote = {Epitaxial growth of (Ba{sub x}Sr{sub 1−x})SnO{sub 3} films with 0 ≤ x ≤ 1 using molecular beam epitaxy is reported. It is shown that SrSnO{sub 3} films can be grown coherently strained on closely lattice and symmetry matched PrScO{sub 3} substrates. The evolution of the optical band gap as a function of composition is determined by spectroscopic ellipsometry. The direct band gap monotonously decreases with x from to 4.46 eV (x = 0) to 3.36 eV (x = 1). A large Burnstein-Moss shift is observed with La-doping of BaSnO{sub 3} films. The shift corresponds approximately to the increase in Fermi level and is consistent with the low conduction band mass.},
doi = {10.1116/1.4959004},
journal = {Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films},
number = 5,
volume = 34,
place = {United States},
year = 2016,
month = 9
}
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