A method for manufacturing a semiconductor device includes forming an oxide film uniformly in a trench in the device isolation by, for example, a radical oxidation process. A cavity dam defines a continuous air bearing surface that extends over a region between the sides of the slider and between at least one sub-ambient cavity and the leading edge. The outer portion of the filled plated through hole is thicker than the center portion and tapered toward the center portion to form a depressed surface on the filled plated through hole.