Phase separations of amorphous CoW films during oxidation and reactions with Si and Al

Journal Article · Wed Mar 01 04:00:00 EST 1989 · J. Appl. Phys.; (United States)

DOI:https://doi.org/10.1063/1.342885· OSTI ID:6760196

Wang, S Q; Mayer, J W

Reactions of thin Co/sub 55/ W/sub 45/ films in contact with Si(100) substrates and aluminum overlayers annealed in vacuum in the temperature ranges of 625--700 /sup 0/C and 500--600 /sup 0/C, respectively, and of thin Co/sub 55/W/sub 45/ films in air from 500 to 600 /sup 0/C were investigated by Rutherford backscattering spectrometry, glancing angle x-ray diffraction, and scanning electron microscope techniques. CoW alloy films were amorphous and have a crystallization temperature of 850 /sup 0/C on SiO/sub 2/ substrates. The compound formed is Co/sub 7/ W/sub 6/. Phase separations were found in all the reactions. A layer of cobalt compounds (CoSi/sub 2/ in Si/CoW, Co/sub 2/ Al/sub 9/ in CoW/Al, and Co/sub 3/ O/sub 4/ in CoW with air) was found to form at the reaction interfaces. In addition, a layer of mainly tungsten compounds (WSi/sub 2/ in Si/CoW, WAl/sub 12/ in CoW/Al, and WO/sub 3/ in CoW with air) was found next to cobalt compound layers, but further away from the reaction interfaces. The reactions started at temperatures comparable to those required for the formation of corresponding tungsten compounds.

• Research Organization: Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853
• OSTI ID: 6760196
• Journal Information: J. Appl. Phys.; (United States), Journal Name: J. Appl. Phys.; (United States) Vol. 65:5; ISSN JAPIA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102* -- Metals & Alloys-- Structure & Phase Studies
360105 -- Metals & Alloys-- Corrosion & Erosion
ALLOYS
ALUMINIUM
ALUMINIUM COMPOUNDS
AMORPHOUS STATE
BACKSCATTERING
CHALCOGENIDES
CHEMICAL REACTIONS
COBALT ALLOYS
COBALT BASE ALLOYS
COBALT COMPOUNDS
COBALT SILICIDES
COHERENT SCATTERING
CRYSTALLIZATION
DIFFRACTION
ELECTRON MICROSCOPY
ELEMENTS
FILMS
HIGH TEMPERATURE
INTERFACES
LAYERS
METALS
MICROSCOPY
MINERALS
OXIDATION
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
PHASE STUDIES
PHASE TRANSFORMATIONS
REFRACTORY METAL COMPOUNDS
SCANNING ELECTRON MICROSCOPY
SCATTERING
SEMIMETALS
SILICA
SILICIDES
SILICON
SILICON COMPOUNDS
SILICON OXIDES
THIN FILMS
TRANSITION ELEMENT COMPOUNDS
TUNGSTEN ALLOYS
TUNGSTEN COMPOUNDS
TUNGSTEN OXIDES
VERY HIGH TEMPERATURE
X-RAY DIFFRACTION