A REACTIVE ION MILLING PROCESS FOR PATTERNING NARROW TRACK IRON NITRIDE RECORDING HEAD POLES AT THE WAFER LEVEL

A thin metal mask is desirable when defining narrow structures by ion milling. This article explores the definition of narrow high moment ir on nitride inductive head pole structures by ion milling in Ar/O-2 and Ar/N-2 gas environments through a Ti mask. Modest ion milling selecti vities between Ti and the iron nitrides (FeAlN and FeTaN) were achieve d by ion milling in Ar/O-2, although the mill rate of the iron nitride s was reduced dramatically. Selectivities of over 4 were achieved by i on milling in Ar/N-2 ambient, without severely reducing the ion millin g rates of the iron nitrides. Hence this reactive mill process is a vi able method for defining narrow iron nitride poles by ion milling at t he wafer level.