Abstract: A surface of a work piece, in which a plurality of magnetic head elements are formed on a substrate, is linearly ground. The surface is linearly ground by an outer circumferential face of a disk-shaped rotary grind stone. By the linear grind, linear grind traces are formed in the work piece. By selecting the direction of the grind traces, amount and direction of warping the work piece can be controlled. By making the direction of the grind traces parallel to a direction of cutting of the work piece to form a plurality of blocks, in each of which a plurality of magnetic head elements are arranged, stress in the blocks are released and the amount of warping of the blocks can be reduced.

Abstract: A surface of a work piece 10, in which a plurality of magnetic head elements are formed on a substrate, is linearly ground. The surface is linearly ground by an outer circumferential face of a disk-shaped rotary grind stone 32. By the linear grind, linear grind traces are formed in the work piece 10. By selecting the direction of the grind traces, amount and direction of warping the work piece can be controlled. By making the direction of the grind traces parallel to a direction of cutting the work piece 10 to form a plurality of blocks, in each of which a plurality of magnetic head elements are arranged, stress in the blocks are released and amount of warping the blocks can be reduced.

Abstract: A filmed head slider, which is capable of writing data with high density, can be made by uniformly machining film layers formed on a wafer for making the filmed head sliders. The method of machining the wafer comprises the steps of: measuring curvature of the filmed surface of the wafer; selecting a machining plate having a machining face, whose curvature is in accord with that of the filmed surface of the wafer, on the basis of the result of the measuring step; and machining the filmed surface of the wafer with the selected ma chining plate.