DYNAMIC HARD MAGNET THICKNESS ADJUSTMENT FOR REDUCED VARIATION IN FREE LAYER STABILIZATION FIELD IN A MAGNETORESISTIVE SENSOR

摘要

A method for manufacturing a current perpendicular to plane magnetoresistive sensor that allows for dynamic adjustment of free layer biasing to compensate for variations in thickness of an electrically insulating layer that separates the hard bias layers from the free layer. During fabrication of the sensor, the actual thickness of the insulation layers is measured. Then, to maintain a desired magnetic stabilization of the free layer one of three options can be utilized. Option one; adjust the stripe height target to maintain the desired magnetic stabilization. Option two; adjust the hard magnet thickness to maintain the desired magnetic stabilization. Option three; use a combination of option one and option two, adjusting both the stripe height target and the hard magnet thickness to maintain the desired magnetic stabilization.