International Business Machines Corporation
Electrolessly formed high resistivity magnetic materials

Abstract:

Present disclosure relates to magnetic materials, chips having magnetic materials, and methods of forming magnetic materials. In certain embodiments, magnetic materials may include a seed layer, and a cobalt-based alloy formed on seed layer. The seed layer may include copper, cobalt, nickel, platinum, palladium, ruthenium, iron, nickel alloy, cobalt-iron-boron alloy, nickel-iron alloy, and any combination of these materials. In certain embodiments, the chip may include one or more on-chip magnetic structures. Each on-chip magnetic structure may include a seed layer, and a cobalt-based alloy formed on seed layer. In certain embodiments, method may include: placing a seed layer in an aqueous electroless plating bath to form a cobalt-based alloy on seed layer. In certain embodiments, the aqueous electroless plating bath may include sodium tetraborate, an alkali metal tartrate, ammonium sulfate, cobalt sulfate, ferric ammonium sulfate and sodium borohydride and has a pH between about 9 to about 13.