Headway Technologies, Incorporated

Xue Hua Wu

Kochan Ju

Jei-Wei Chang

Yining Hu

Henry C Chang

Yi-Chun Liu

Si-Tuan Lam

Wensen Li

Write head coils for magnetic disk systems are commonly formed through electroplating onto a seed layer in the presence of a photoresist mask. It is then necessary to remove the seed layer everywhere except under the coil itself. The present invention achieves this through etching in a solution of ammonium persulfate to which has been added the complexing agent 1,4,8,11 tetraazundecane. This suppresses the reduction of Cu to Cu, thereby increasing the dissolution rate of copper while decreasing that of nickel-iron. Two ways of implementing this are described&mdash;adding the complexing agent directly to the ammonium persulfate and introducing the 1,4,8,11 tetraazundecane through a dipping process that precedes conventional etching in the ammonium persulfate.

Etching process to selectively remove copper plating seed layer

A method for forming a plated layer. There is first provided a substrate. There is then formed over the substrate a masking frame employed for masking frame plating a masking frame plated layer within the masking frame, where the masking frame is fabricated to provide an overhang of an upper portion of the masking frame spaced further from the substrate with respect to a lower portion of the masking frame spaced closer to the substrate. Finally, there is then plated the masking frame plated layer within the masking frame. The method is useful for forming masking frame plated magnetic pole tip stack layers with enhanced planarity dimensional control within magnetic transducer elements.

Masking frame plating method for forming masking frame plated layer

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Union City, CA, United States of America

Xue Hua Wu