Abstract: A method makes a magnetic head having a top and a bottom, front and rear ends and an air bearing surface (ABS) at the front end, comprising the steps of forming first and second pole piece layers with the first and second pole piece layers separated by a write gap layer at the ABS and connected at a back gap that is recessed rearwardly in the head from the ABS; forming a zero throat height (ZTH) defining layer of baked photoresist that is sandwiched between the first and second pole piece layers with the ZTH defining layer having a rounded front edge where the first and second pole piece layers first separate from one another after the ABS to define the ZTH; and forming an insulation stack with a coil layer embedded therein between the first and second pole piece layers with the insulation stack placed so that the ZTH defining layer is located entirely between the ABS and the coil layer.

Abstract: A strip of baked photoresist is employed for defining the zero throat height (ZTH) of a write head portion of a merged head. The zero throat height is the location where first and second pole pieces of the write head first commence to separate after an air bearing surface (ABS) of the write head for reducing flux leakage therebetween. A read head portion of the merged head includes a read sensor that has a recessed edge. The recessed edge defines a stripe height of the read head. The stripe height, which is the distance between the ABS and the recessed edge, establishes the magnetics of the read head. The present invention more accurately positions the ZTH with improved predictability relative to the stripe height since there is minimal shrinkage of the photoresist strip during a baking step. Further the photoresist strip has a desirable apex angle at its front ZTH defining edge for minimizing flux leakage between the pole pieces.