Published December 3, 2012 | Version v1
Journal article

Integration of high-dielectric constant Ta2O5 oxides on diamond for power devices

  • 1. Optical and Electronic Materials Unit, National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)
  • 2. State Key Laboratory of Superhard Materials, Jilin University, Changchun 130012 (China)
  • 3. International Center for Young Scientists (ICYS), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)
  • 4. Center of Materials Research for Low Carbon Emission, NIMS, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)
  • 5. Nanofabrication Platform, NIMS, 1-2-1 Sengen, Tsukuba, Ibaraki 305–0047 (Japan)

Description

The authors report on the direct integration of high-dielectric constant (high-k) Ta2O5 films on p-type single crystal diamond for high-power electronic devices. Crystallized hexagonal phase δ-Ta2O5 film is achieved on diamond by annealing the amorphous Ta2O5 film deposited by a sputter-deposition technique. The electrical properties of the Ta2O5 thin films are investigated by fabricating metal-insulator-semiconductor (MIS) diodes. The leakage current of the MIS diode is as low as 10−8 A/cm2 for the as-deposited amorphous Ta2O5 film and 10−2 A/cm2 for the crystallized film, which is 108 and 102 times lower than that of the Schottky diode at a forward bias of −3 V, respectively. The dielectric constant of the amorphous Ta2O5 films is measured to be 16 and increases to 29 after annealing at 800 °C. Different current leakage mechanisms and charge trapping behaviors are proposed for the amorphous and crystallized Ta2O5 thin films.

Additional details

Identifiers

Publishing Information

Journal Title
Applied Physics Letters
Journal Volume
101
Journal Issue
23
Journal Page Range
p. 232907-232907.5
ISSN
0003-6951
CODEN
APPLAB

Optional Information

Notes
(c) 2012 American Institute of Physics