Patent ID: 6821715
Filing Date: 2004-11-23
Classification: B82Y,G11B,Y10T

Abstract:
A method for fabricating a magnetoresistive (MR) sensor comprising:a) depositing a bottom layer on a substrate, wherein the substrate is a magnetoresistive layer structure and the bottom layer comprises a first polymer; b) depositing a top resist layer on the bottom layer, the top resist layer comprising a second polymer; c) exposing the top resist layer to energetic particles in a bridge pattern defining a trackwidth of the MR sensor; d) developing the exposed top resist layer with a second developer which substantially does not affect the bottom layer; e) etching the bottom layer in a first developer to form a fully undercut resist bridge structure suspended above the substrate, wherein the resist bridge has a width narrower than 0.2 micron, and wherein the first developer substantially does not affect the top resist layer; and f) ion beam milling the magnetoresistive layer structure to form the magnetoresistive sensor, wherein the magnetoresistive sensor has a trackwidth narrower than 0.2 microns; wherein a pattern is not formed in said bottom layer by exposure to said energetic particles or by exposure to other energetic particles.