Operation of ohmic Ti/Al/Pt/Au multilayer contacts to GaN at 600 °C in air

Journal Article · Mon Aug 25 00:00:00 EDT 2014 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4894290· OSTI ID:22310946

Hou, Minmin ^[1]; Senesky, Debbie G. ^[1]

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1. Department of Electrical Engineering, Stanford University, Stanford, California 94305 (United States)

The high-temperature characteristics (at 600 °C) of Ti/Al/Pt/Au multilayer contacts to gallium nitride (GaN) in air are reported. Microfabricated circular-transfer-line-method test structures were subject to 10 h of thermal storage at 600 °C. Intermittent electrical characterization during thermal storage showed minimal variation in the contact resistance after 2 h and that the specific contact resistivity remained on the order of 10{sup −5} Ω-cm{sup 2}. In addition, the thermally stored multilayer contacts to GaN showed ohmic I-V characteristics when electrically probed at 600 °C. The microstructural analysis with atomic force microscopy showed minimal changes in surface roughness after thermal storage. Observations of the thermochemical reactions after thermal storage using Auger electron spectroscopy chemical depth profiling showed diffusion of Pt and minimal additional Al oxidation. The results support the use of Ti/Al/Pt/Au multilayer metallization for GaN-based sensors and electronic devices that will operate within a high-temperature and oxidizing ambient.

• OSTI ID: 22310946
• Journal Information: Applied Physics Letters, Vol. 105, Issue 8; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALUMINIUM
ATOMIC FORCE MICROSCOPY
AUGER ELECTRON SPECTROSCOPY
DIFFUSION
ELECTRIC CONDUCTIVITY
ELECTRIC CONTACTS
ELECTRONIC EQUIPMENT
GALLIUM NITRIDES
GOLD
HEAT STORAGE
LAYERS
MICROSTRUCTURE
OXIDATION
PLATINUM
ROUGHNESS
SURFACES
TEMPERATURE RANGE 0400-1000 K
TITANIUM