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Title: Dielectric and Optical Properties of Epitaxial Rare-Earth Scandate Films and Their Crystallization Behavior

Abstract

Rare-earth scandates (ReScO{sub 3}, with Re = Y, La, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu, i.e., the entire series for which the individual oxides are chemically stable in contact with Si) were deposited in a temperature-gradient pulsed laser deposition system onto LaAlO{sub 3} substrates. The crystallization temperature depends monotonically on the Re atomic number and the Goldschmidt tolerance factor, with crystallization temperatures as low as 650 C for LaScO{sub 3} and PrScO{sub 3}. The dielectric constants of the crystalline films K {approx} 30 (determined by microwave microscopy) are significantly larger than those of their amorphous counterparts. In combination with the large observed band gaps (E{sub g} > 5.5 eV, determined by ellipsometry), these results indicate the potential of these materials as high-K dielectrics for field-effect transistor applications.

Authors:
 [1];  [1];  [2];  [3];  [3];  [4];  [4];  [5];  [5]
  1. ORNL
  2. University of Tokyo, Tokyo, Japan
  3. George Washington University
  4. Portland State University
  5. Pennsylvania State University
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1003590
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 88; Journal Issue: 26
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ATOMIC NUMBER; CRYSTALLIZATION; DEPOSITION; DIELECTRIC MATERIALS; ELLIPSOMETRY; FIELD EFFECT TRANSISTORS; LASERS; MICROSCOPY; OPTICAL PROPERTIES; OXIDES; PERMITTIVITY; SUBSTRATES; TOLERANCE

Citation Formats

Christen, Hans M, Jellison Jr, Gerald Earle, Ohkubo, I., HUANG, S., Reeves, M. E., Cicerrella, E., Freeouf, J. L., Jia, Y., and Schlom, D. G.. Dielectric and Optical Properties of Epitaxial Rare-Earth Scandate Films and Their Crystallization Behavior. United States: N. p., 2006. Web. doi:10.1063/1.2213931.
Christen, Hans M, Jellison Jr, Gerald Earle, Ohkubo, I., HUANG, S., Reeves, M. E., Cicerrella, E., Freeouf, J. L., Jia, Y., & Schlom, D. G.. Dielectric and Optical Properties of Epitaxial Rare-Earth Scandate Films and Their Crystallization Behavior. United States. doi:10.1063/1.2213931.
Christen, Hans M, Jellison Jr, Gerald Earle, Ohkubo, I., HUANG, S., Reeves, M. E., Cicerrella, E., Freeouf, J. L., Jia, Y., and Schlom, D. G.. Sun . "Dielectric and Optical Properties of Epitaxial Rare-Earth Scandate Films and Their Crystallization Behavior". United States. doi:10.1063/1.2213931.
@article{osti_1003590,
title = {Dielectric and Optical Properties of Epitaxial Rare-Earth Scandate Films and Their Crystallization Behavior},
author = {Christen, Hans M and Jellison Jr, Gerald Earle and Ohkubo, I. and HUANG, S. and Reeves, M. E. and Cicerrella, E. and Freeouf, J. L. and Jia, Y. and Schlom, D. G.},
abstractNote = {Rare-earth scandates (ReScO{sub 3}, with Re = Y, La, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu, i.e., the entire series for which the individual oxides are chemically stable in contact with Si) were deposited in a temperature-gradient pulsed laser deposition system onto LaAlO{sub 3} substrates. The crystallization temperature depends monotonically on the Re atomic number and the Goldschmidt tolerance factor, with crystallization temperatures as low as 650 C for LaScO{sub 3} and PrScO{sub 3}. The dielectric constants of the crystalline films K {approx} 30 (determined by microwave microscopy) are significantly larger than those of their amorphous counterparts. In combination with the large observed band gaps (E{sub g} > 5.5 eV, determined by ellipsometry), these results indicate the potential of these materials as high-K dielectrics for field-effect transistor applications.},
doi = {10.1063/1.2213931},
journal = {Applied Physics Letters},
number = 26,
volume = 88,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
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