Title :
Enhancing CoCr(Pt)Ta target´s pass-through flux for magnetron sputtering
Author :
Schlott, M. ; Weigert, M. ; Gehman, B.L.
Author_Institution :
Degussa AG, Hanau, Germany
fDate :
11/1/1995 12:00:00 AM
Abstract :
The transmitted DC magnetic field for CoCr(Pt)Ta sputtering targets, containing 2-6 at.% Ta and 0 11 at.% Pt, on magnetron cathodes is investigated. If the Ta content exceeds the solubility limit of 1.5-2 at.%, heat treatment just below the peritectic temperature for Co7 Ta2 formation results in the transformation of λ 3/Co2Ta precipitates or dissolved Ta into Co7 Ta2 phase. Finely dispersed Co7Ta2 precipitates are formed which seem to exert enough lattice strain to support the martensitic transformation of high-temperature fcc into room temperature hcp Co-Cr solid solution. Since the space-averaged hcp Co-Cr crystal has a lower permeability than the fcc crystal, such target material shows at least a 60% increase in its transmitted magnetic field on magnetron cathodes
Keywords :
chromium alloys; cobalt alloys; ferromagnetic materials; heat treatment; magnetic thin films; martensitic transformations; platinum alloys; precipitation; solid solutions; sputter deposition; tantalum alloys; CoCrPtTa; CoCrTa; DC magnetic field; heat treatment; high-temperature FCC crystal; lattice strain; magnetron cathodes; magnetron sputtering; martensitic transformation; pass-through flux; peritectic temperature; permeability; precipitates; room temperature HCP crystal; solid solution; solubility; sputtering targets; Cathodes; Heat treatment; Lattices; Magnetic field induced strain; Magnetic fields; Magnetic flux; Magnetic materials; Solids; Sputtering; Temperature;
Journal_Title :
Magnetics, IEEE Transactions on
