Patent ID: 7741133

Claim:
A method of testing resistances of helical coils formed in magnetic recording heads on a wafer, wherein the helical coils include a bottom coil structure, a top coil structure, and a plurality of connecting structures that electrically connect the bottom coil structure and the top coil structure to define a helical coil, the method comprising: fabricating a test component on the wafer along with the magnetic recording heads, wherein the test component includes a bottom coil structure connected in series, and also includes a top coil structure connected in series which is electrically disconnected from the bottom coil structure; measuring a resistance of the bottom coil structure in the test component; measuring a resistance of the top coil structure in the test component; measuring a total resistance of a helical coil that is fabricated on the wafer; and determining the resistance of the connecting structures in the helical coil based on the resistance of the bottom coil structure, the resistance of the top coil structure, and the total resistance of the helical coil.