Method for Measuring Write Coil to Air Bearing Surface Impedance for Magnetic Thin Film Head
Original Publication Date: 1988-Nov-01
Included in the Prior Art Database: 2005-Feb-15
In the manufacture of magnetic thin film heads, it is frequently necessary to measure magnetic head write coil to air bearing surface (ABS) impedance. Direct measurements of the write coil to ABS impedance have traditionally required the use of gallium-indium in contact with the ABS. The disadvantages of such measurements include the toxic nature of gallium-indium and the difficulty in cleaning it from the ABS. Substitute measurements of write coil to write coil impedance can be used, by yield impedance values not necessarily indicative of the write coil to ABS impedance. The problem thus presented is how to measure the write coil to ABS impedance using non-toxic materials which are easily cleaned from the ABS, and which are non-corrosive to the head.