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Title: Influence of oxygen content on the structural and electrical characteristics of thin neodymium oxide gate dielectrics

Abstract

The structural properties and electrical characteristics of thin Nd{sub 2}O{sub 3} gate oxides were deposited on silicon substrates by reactive rf sputtering. The structural and morphological features of these films were studied, as a function of the growth conditions (three various argon-to-oxygen flow ratios: 20/5, 15/10, and 12.5/12.5 and temperature from 600 to 800 degree sign C), by x-ray diffraction, atomic force microscopy, and x-ray photoelectron spectroscopy. It is found that Nd{sub 2}O{sub 3} dielectrics with a 12.5/12.5 ratio condition annealed at 700 degree sign C exhibit a thinner capacitance equivalent thickness and excellent electrical properties, including the electric breakdown field, the interface trap density, the hysteresis, and frequency dispersion in the capacitance-voltage curves. This condition is suggested to the reduction of the interfacial SiO{sub 2} and silicate formation, and the small of surface roughness due to the optimization of oxygen in the metal oxide film.

Authors:
; ;  [1]
  1. Department of Electronics Engineering, Chang Gung University, Taoyuan 333, Taiwan (China)
Publication Date:
OSTI Identifier:
20982644
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 101; Journal Issue: 2; Other Information: DOI: 10.1063/1.2426937; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ANNEALING; ARGON; ATOMIC FORCE MICROSCOPY; CAPACITANCE; CRYSTAL GROWTH; DISPERSIONS; ELECTRIC POTENTIAL; HYSTERESIS; NEODYMIUM OXIDES; OXYGEN; SILICATES; SILICON OXIDES; SPUTTERING; SURFACE COATING; TEMPERATURE DEPENDENCE; TEMPERATURE RANGE 0400-1000 K; TEMPERATURE RANGE 1000-4000 K; THIN FILMS; X-RAY DIFFRACTION; X-RAY PHOTOELECTRON SPECTROSCOPY

Citation Formats

Pan, Tung-Ming, Lee, Jian-Der, and Yeh, Wen-Wei. Influence of oxygen content on the structural and electrical characteristics of thin neodymium oxide gate dielectrics. United States: N. p., 2007. Web. doi:10.1063/1.2426937.
Pan, Tung-Ming, Lee, Jian-Der, & Yeh, Wen-Wei. Influence of oxygen content on the structural and electrical characteristics of thin neodymium oxide gate dielectrics. United States. doi:10.1063/1.2426937.
Pan, Tung-Ming, Lee, Jian-Der, and Yeh, Wen-Wei. Mon . "Influence of oxygen content on the structural and electrical characteristics of thin neodymium oxide gate dielectrics". United States. doi:10.1063/1.2426937.
@article{osti_20982644,
title = {Influence of oxygen content on the structural and electrical characteristics of thin neodymium oxide gate dielectrics},
author = {Pan, Tung-Ming and Lee, Jian-Der and Yeh, Wen-Wei},
abstractNote = {The structural properties and electrical characteristics of thin Nd{sub 2}O{sub 3} gate oxides were deposited on silicon substrates by reactive rf sputtering. The structural and morphological features of these films were studied, as a function of the growth conditions (three various argon-to-oxygen flow ratios: 20/5, 15/10, and 12.5/12.5 and temperature from 600 to 800 degree sign C), by x-ray diffraction, atomic force microscopy, and x-ray photoelectron spectroscopy. It is found that Nd{sub 2}O{sub 3} dielectrics with a 12.5/12.5 ratio condition annealed at 700 degree sign C exhibit a thinner capacitance equivalent thickness and excellent electrical properties, including the electric breakdown field, the interface trap density, the hysteresis, and frequency dispersion in the capacitance-voltage curves. This condition is suggested to the reduction of the interfacial SiO{sub 2} and silicate formation, and the small of surface roughness due to the optimization of oxygen in the metal oxide film.},
doi = {10.1063/1.2426937},
journal = {Journal of Applied Physics},
number = 2,
volume = 101,
place = {United States},
year = {Mon Jan 15 00:00:00 EST 2007},
month = {Mon Jan 15 00:00:00 EST 2007}
}
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