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Title: Integration of high-dielectric constant Ta{sub 2}O{sub 5} oxides on diamond for power devices

Abstract

The authors report on the direct integration of high-dielectric constant (high-k) Ta{sub 2}O{sub 5} films on p-type single crystal diamond for high-power electronic devices. Crystallized hexagonal phase {delta}-Ta{sub 2}O{sub 5} film is achieved on diamond by annealing the amorphous Ta{sub 2}O{sub 5} film deposited by a sputter-deposition technique. The electrical properties of the Ta{sub 2}O{sub 5} thin films are investigated by fabricating metal-insulator-semiconductor (MIS) diodes. The leakage current of the MIS diode is as low as 10{sup -8} A/cm{sup 2} for the as-deposited amorphous Ta{sub 2}O{sub 5} film and 10{sup -2} A/cm{sup 2} for the crystallized film, which is 10{sup 8} and 10{sup 2} times lower than that of the Schottky diode at a forward bias of -3 V, respectively. The dielectric constant of the amorphous Ta{sub 2}O{sub 5} films is measured to be 16 and increases to 29 after annealing at 800 Degree-Sign C. Different current leakage mechanisms and charge trapping behaviors are proposed for the amorphous and crystallized Ta{sub 2}O{sub 5} thin films.

Authors:
 [1];  [2];  [3]; ;  [4]; ;  [1];  [4];  [5];  [5]
  1. State Key Laboratory of Superhard Materials, Jilin University, Changchun 130012 (China)
  2. (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)
  3. International Center for Young Scientists (ICYS), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)
  4. Optical and Electronic Materials Unit, National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)
  5. (Japan)
Publication Date:
OSTI Identifier:
22089583
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 101; Journal Issue: 23; Other Information: (c) 2012 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ANNEALING; BERYLLIUM 16; CRYSTALLIZATION; DEPOSITION; DIAMONDS; DIELECTRIC MATERIALS; ELECTRONIC EQUIPMENT; LEAKAGE CURRENT; METALS; MONOCRYSTALS; PERMITTIVITY; SCHOTTKY BARRIER DIODES; SEMICONDUCTOR MATERIALS; SPUTTERING; TANTALUM OXIDES; THIN FILMS; TRAPPING

Citation Formats

Cheng Shaoheng, Optical and Electronic Materials Unit, National Institute for Materials Science, Sang Liwen, Liao Meiyong, Imura, Masataka, Liu Jiangwei, Li Hongdong, Koide, Yasuo, Nanofabrication Platform, NIMS, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, and Center of Materials Research for Low Carbon Emission, NIMS, 1-1 Namiki, Tsukuba, Ibaraki 305-0044. Integration of high-dielectric constant Ta{sub 2}O{sub 5} oxides on diamond for power devices. United States: N. p., 2012. Web. doi:10.1063/1.4770059.
Cheng Shaoheng, Optical and Electronic Materials Unit, National Institute for Materials Science, Sang Liwen, Liao Meiyong, Imura, Masataka, Liu Jiangwei, Li Hongdong, Koide, Yasuo, Nanofabrication Platform, NIMS, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, & Center of Materials Research for Low Carbon Emission, NIMS, 1-1 Namiki, Tsukuba, Ibaraki 305-0044. Integration of high-dielectric constant Ta{sub 2}O{sub 5} oxides on diamond for power devices. United States. doi:10.1063/1.4770059.
Cheng Shaoheng, Optical and Electronic Materials Unit, National Institute for Materials Science, Sang Liwen, Liao Meiyong, Imura, Masataka, Liu Jiangwei, Li Hongdong, Koide, Yasuo, Nanofabrication Platform, NIMS, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, and Center of Materials Research for Low Carbon Emission, NIMS, 1-1 Namiki, Tsukuba, Ibaraki 305-0044. 2012. "Integration of high-dielectric constant Ta{sub 2}O{sub 5} oxides on diamond for power devices". United States. doi:10.1063/1.4770059.
@article{osti_22089583,
title = {Integration of high-dielectric constant Ta{sub 2}O{sub 5} oxides on diamond for power devices},
author = {Cheng Shaoheng and Optical and Electronic Materials Unit, National Institute for Materials Science and Sang Liwen and Liao Meiyong and Imura, Masataka and Liu Jiangwei and Li Hongdong and Koide, Yasuo and Nanofabrication Platform, NIMS, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 and Center of Materials Research for Low Carbon Emission, NIMS, 1-1 Namiki, Tsukuba, Ibaraki 305-0044},
abstractNote = {The authors report on the direct integration of high-dielectric constant (high-k) Ta{sub 2}O{sub 5} films on p-type single crystal diamond for high-power electronic devices. Crystallized hexagonal phase {delta}-Ta{sub 2}O{sub 5} film is achieved on diamond by annealing the amorphous Ta{sub 2}O{sub 5} film deposited by a sputter-deposition technique. The electrical properties of the Ta{sub 2}O{sub 5} thin films are investigated by fabricating metal-insulator-semiconductor (MIS) diodes. The leakage current of the MIS diode is as low as 10{sup -8} A/cm{sup 2} for the as-deposited amorphous Ta{sub 2}O{sub 5} film and 10{sup -2} A/cm{sup 2} for the crystallized film, which is 10{sup 8} and 10{sup 2} times lower than that of the Schottky diode at a forward bias of -3 V, respectively. The dielectric constant of the amorphous Ta{sub 2}O{sub 5} films is measured to be 16 and increases to 29 after annealing at 800 Degree-Sign C. Different current leakage mechanisms and charge trapping behaviors are proposed for the amorphous and crystallized Ta{sub 2}O{sub 5} thin films.},
doi = {10.1063/1.4770059},
journal = {Applied Physics Letters},
number = 23,
volume = 101,
place = {United States},
year = 2012,
month =
}
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