a method of manufacturing a thin film merged magnetic head including an inductive write structure and a magnetoresistive sensor uses a patterned protection layer to protect a second shield / bottom pole layer in regions spaced from the pole tip of the inductive write structure . a window is provided in the protection layer . during manufacture , the configuration comprises a first shield layer , a magnetoresistive element , a second shield layer serving as a bottom pole , a protection layer , a protection window , a write gap , a top pole , and a pole tip structure . the use of a protection layer and window results in the formation of channels in the second shield layer adjacent to a pedestal that supports the inductive write structure . the channels prevent magnetic flux from extending toward the second shield layer beyond the width of the pole tip structure . this structure reduces side writing with a consequent improvement in off - track performance . the width of the second shield layer allows the magnetoresistive element to be shielded .