Electroplated permalloy for bubble propagation and detection

A description is given of the fabrication conditions and magnetic properties of electroplated permalloy for bubble circuits. Propagation and detection elements are grown in stencils delineated in the resist. The plating base is a thin Cr-Cu layer which is chemically etched. A 2% magnetoresistive ratio is obtained with the 12% Fe composition yielding signals of 1 mV/mA. Propagation margins and detection signals are comparable to those given by circuits fabricated by vacuum deposition methods.