Low-resistivity and transparent indium-oxide-doped ZnO ohmic contact to p-type GaN

Journal Article · Mon Dec 20 00:00:00 EST 2004 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.1826231· OSTI ID:20634572

Lim, Jae-Hong; Hwang, Dae-Kue; Kim, Hyun-Sik; Oh, Jin-Yong; Yang, Jin-Ho; Navamathavan, R; Park, Seong-Ju ^[1]

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1. Department of Materials Science and Engineering and National Research Laboratory for Nanophotonic Semiconductors, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of)

We report on the indium-oxide-doped ZnO (IZO) transparent ohmic contact to the p-GaN. The IZO transparent ohmic contact layer was deposited on p-GaN by e-beam evaporation. The transmittance of an IZO film with a thickness of 250 nm was 84%-92% for the light in the wavelength range of 400 and 600 nm. In addition, the IZO contact film yielded a low specific contact resistance of 3.4x10{sup -4} {omega} cm{sup 2} on p-GaN when annealed at 600 deg. C for 5 min under a nitrogen ambient. Auger electron spectroscopy and x-ray photoemission spectroscopy analyses of the IZO and p-GaN interface indicated that Ga atoms had out-diffused and an InN phase was formed at the interface region after the thermal annealing process, resulting in a decrease in contact resistance. The light output power of a light-emitting diode (LED) with an IZO ohmic contact layer was increased by 34% at 83 mW of electrical input power compared to that of a LED with a Ni/Au ohmic contact layer.

• OSTI ID: 20634572
• Journal Information: Applied Physics Letters, Vol. 85, Issue 25; Other Information: DOI: 10.1063/1.1826231; (c) 2004 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ANNEALING
AUGER ELECTRON SPECTROSCOPY
DOPED MATERIALS
ELECTRIC CONDUCTIVITY
ELECTRON BEAMS
EVAPORATION
GALLIUM NITRIDES
INDIUM NITRIDES
INDIUM OXIDES
LAYERS
LIGHT EMITTING DIODES
NITROGEN
PHOTOEMISSION
SEMICONDUCTOR MATERIALS
THIN FILMS
VACUUM COATING
X-RAY PHOTOELECTRON SPECTROSCOPY
ZINC OXIDES