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Title: Depth profiling of dielectric SrTiO{sub 3} thin films by angle-resolved x-ray photoelectron spectroscopy

Abstract

This letter reports the results from using angle-resolved x-ray photoelectron spectroscopy to nondestructively characterize ultrathin high-k SrTiO{sub 3} (STO) films. Results indicate that carbon is present in the STO film in the form of SrCO{sub 3} which is amorphous. SrCO{sub 3} concentration varies as a function of its position in the film as measured by the take-off angle (TOA). For films annealed at 650 deg. C, the C 1s, O 1s, and Sr 3d photoelectron transitions indicate a significant reduction in the carbonate. There is Sr enrichment on the surface, and the composition gradually converges to stoichiometric STO with Sr/Ti{approx}1 at higher TOA.

Authors:
; ;  [1]
  1. Micron Technology, Inc., 8000 S. Federal Way, Boise, Idaho 83706 (United States)
Publication Date:
OSTI Identifier:
20880189
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 89; Journal Issue: 25; Other Information: DOI: 10.1063/1.2410232; (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; ANNEALING; CARBON; CARBONATES; DIELECTRIC MATERIALS; NONDESTRUCTIVE TESTING; STOICHIOMETRY; STRONTIUM TITANATES; TEMPERATURE RANGE 0400-1000 K; THIN FILMS; X-RAY PHOTOELECTRON SPECTROSCOPY

Citation Formats

Bhaskar, S., Allgeyer, Dan, and Smythe, John A. III. Depth profiling of dielectric SrTiO{sub 3} thin films by angle-resolved x-ray photoelectron spectroscopy. United States: N. p., 2006. Web. doi:10.1063/1.2410232.
Bhaskar, S., Allgeyer, Dan, & Smythe, John A. III. Depth profiling of dielectric SrTiO{sub 3} thin films by angle-resolved x-ray photoelectron spectroscopy. United States. doi:10.1063/1.2410232.
Bhaskar, S., Allgeyer, Dan, and Smythe, John A. III. Mon . "Depth profiling of dielectric SrTiO{sub 3} thin films by angle-resolved x-ray photoelectron spectroscopy". United States. doi:10.1063/1.2410232.
@article{osti_20880189,
title = {Depth profiling of dielectric SrTiO{sub 3} thin films by angle-resolved x-ray photoelectron spectroscopy},
author = {Bhaskar, S. and Allgeyer, Dan and Smythe, John A. III},
abstractNote = {This letter reports the results from using angle-resolved x-ray photoelectron spectroscopy to nondestructively characterize ultrathin high-k SrTiO{sub 3} (STO) films. Results indicate that carbon is present in the STO film in the form of SrCO{sub 3} which is amorphous. SrCO{sub 3} concentration varies as a function of its position in the film as measured by the take-off angle (TOA). For films annealed at 650 deg. C, the C 1s, O 1s, and Sr 3d photoelectron transitions indicate a significant reduction in the carbonate. There is Sr enrichment on the surface, and the composition gradually converges to stoichiometric STO with Sr/Ti{approx}1 at higher TOA.},
doi = {10.1063/1.2410232},
journal = {Applied Physics Letters},
number = 25,
volume = 89,
place = {United States},
year = {Mon Dec 18 00:00:00 EST 2006},
month = {Mon Dec 18 00:00:00 EST 2006}
}
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