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Title: The influence of surface roughness on the electric conduction process in amorphous Ta{sub 2}O{sub 5} thin films

Abstract

Amorphous Ta{sub 2}O{sub 5} thin films were deposited by radio-frequency magnetron sputtering at the substrate temperatures of 100, 200, and 300 C, respectively. The electrical properties of Ta{sub 2}O{sub 5} thin films were investigated as a function of substrate temperature and film thickness. The leakage current of the Ta{sub 2}O{sub 5} films was in the order of 10{sup {minus}5} to 10{sup {minus}6} A/cm{sup 2} for an applied field of 1 MV/cm. The charge storage capacitances ({epsilon}E{sub breakdown}) were 7.7 (100 C), 7.9 (200 C), and 3.7 (300 C) {micro}C/cm{sup 2}. Most of the electrical analyses were performed with the data obtained for the Ta{sub 2}O{sub 5} thin films deposited at 200 C substrate temperature because they showed optimum electrical properties. The dominant conduction mechanism changed from Schottky emission current at low field to Poole-Frankel current at the high field. With increasing film thickness, the surface roughness increased, whereas the transition fields from the electrode-limited current to the bulk-limited current process decreased. To verify the effect of this surface roughness on the electrical conduction mechanism, a two-dimensional numerical simulator, MEDICI, was used to simulate the electric field distribution at the bulk region of the thin film and the interface region betweenmore » the thin film and electrode.« less

Authors:
; ; ; ;
Publication Date:
Research Org.:
Korea Univ., Seoul (KR)
OSTI Identifier:
20003179
Resource Type:
Journal Article
Journal Name:
Journal of the Electrochemical Society
Additional Journal Information:
Journal Volume: 146; Journal Issue: 9; Other Information: PBD: Sep 1999
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 25 ENERGY STORAGE; ELECTRIC CONDUCTIVITY; TANTALUM OXIDES; THIN FILMS; AMORPHOUS STATE; ROUGHNESS; SURFACE PROPERTIES; CAPACITIVE ENERGY STORAGE EQUIPMENT

Citation Formats

Kim, Y.S., Sung, M.Y., Lee, Y.H., Ju, B.K., and Oh, M.H. The influence of surface roughness on the electric conduction process in amorphous Ta{sub 2}O{sub 5} thin films. United States: N. p., 1999. Web. doi:10.1149/1.1392485.
Kim, Y.S., Sung, M.Y., Lee, Y.H., Ju, B.K., & Oh, M.H. The influence of surface roughness on the electric conduction process in amorphous Ta{sub 2}O{sub 5} thin films. United States. doi:10.1149/1.1392485.
Kim, Y.S., Sung, M.Y., Lee, Y.H., Ju, B.K., and Oh, M.H. Wed . "The influence of surface roughness on the electric conduction process in amorphous Ta{sub 2}O{sub 5} thin films". United States. doi:10.1149/1.1392485.
@article{osti_20003179,
title = {The influence of surface roughness on the electric conduction process in amorphous Ta{sub 2}O{sub 5} thin films},
author = {Kim, Y.S. and Sung, M.Y. and Lee, Y.H. and Ju, B.K. and Oh, M.H.},
abstractNote = {Amorphous Ta{sub 2}O{sub 5} thin films were deposited by radio-frequency magnetron sputtering at the substrate temperatures of 100, 200, and 300 C, respectively. The electrical properties of Ta{sub 2}O{sub 5} thin films were investigated as a function of substrate temperature and film thickness. The leakage current of the Ta{sub 2}O{sub 5} films was in the order of 10{sup {minus}5} to 10{sup {minus}6} A/cm{sup 2} for an applied field of 1 MV/cm. The charge storage capacitances ({epsilon}E{sub breakdown}) were 7.7 (100 C), 7.9 (200 C), and 3.7 (300 C) {micro}C/cm{sup 2}. Most of the electrical analyses were performed with the data obtained for the Ta{sub 2}O{sub 5} thin films deposited at 200 C substrate temperature because they showed optimum electrical properties. The dominant conduction mechanism changed from Schottky emission current at low field to Poole-Frankel current at the high field. With increasing film thickness, the surface roughness increased, whereas the transition fields from the electrode-limited current to the bulk-limited current process decreased. To verify the effect of this surface roughness on the electrical conduction mechanism, a two-dimensional numerical simulator, MEDICI, was used to simulate the electric field distribution at the bulk region of the thin film and the interface region between the thin film and electrode.},
doi = {10.1149/1.1392485},
journal = {Journal of the Electrochemical Society},
number = 9,
volume = 146,
place = {United States},
year = {1999},
month = {9}
}