layer 8 and the second isolation layer 9 thereafter the upper shield layer 7 is formed and electrically coupled to the lower shield layer 6 after the terminal 10 is formed the protection layer 11 is formed and processed by lapping or the like until the terminal 10 is exposed to the surface thereby the terminal 10 is electrically coupled to the lower shield layer 6 and the upper shield layer 7 by grounding the terminal 10 and connecting the current source and the differential amplifier 12 between the remaining terminals 10 the noises of the mr head can be reduced in the same way as the embodiments described before other embodiments of the present invention will now be described fig6 is a sectional view of an embodiment in which the structure of the through hole 23 located at the terminal 13 of the mr head illustrated in fig5 a and 5b is modified after the lower shield layer 6 the first isolation layer 8 the mr element 2 the bias layer 13 the second isolation layer 9 and the upper shield layer 7 are formed all of the layers are etched to make a through hole 24 thereafter a terminal 4 of.