The present invention is a method of using direct head electrical response
signals for feedback process control. When lapping the air bearing
surface of a bar of sliders, a magnetic field is applied to the air
bearing surface and a bias current is applied to the reader elements. A
head electrical response, such as amplitude or resistance change, is
measured and is used to control the lapping device. Using a fixture which
allows individual slider machining, a controller can be used to monitor
the head response signal for each slider on the bar and individually
control each slider on the bar so that material removal over each slider
proceeds until a predetermined target stripe height is reached.