This paper describes the development of a fabrication and etching process f
or the in-situ formation of sacrificial layers in electrodeposited NiFe mag
netic alloys. Sacrificial layers consist of iron-rich material electrodepos
ited in a nickel-rich matrix. The iron-rich layers are formed using a pulse
d electrolyte agitation scheme. The removal of sacrificial layers is invest
igated using a concentrated acid etching procedure as well as a potential-e
nhanced etching technique. The formation of sacrificial layers in electrode
posited microgears and planar films is demonstrated. We find that glacial a
cetic acid preferentially removes the sacrificial layers at a rate of 0.5 m
u m hr(-1) while leaving the remaining nickel-rich structure unaffected. An
applied potential is used to accelerate the etch rate of sacrificial mater
ial in dilute acetic acid as well as in a chloride-based etching solution.
Under potential control, sacrificial layers are etched at rates approaching
80 mu m hr(-1). The remaining nickel-rich matrix is not significantly affe
cted during etching and retains its structural fidelity. NiFe sacrificial l
ayers of varying compositions are shown to etch at rates that depend on the
iron content. The implications for using these techniques in conventional
through-mold plating applications are discussed.