Method for fabricating a magnetic transducer using a slurry with spherical particles for CMP-assisted photoresist lift-off

Abstract

A method is described which uses a CMP slurry with an abrasive of spherical particles to lift-off photoresist used in the patterning of the sensor for a magnetic transducer. The spherical particles are preferably silica, alumina, titania or zirconia with colloidal silica being preferred. The size of the particle is preferably less than 0.015 microns. The pH is preferably alkaline and even more preferably with a pH of about 10-11. In a method according to the invention a CPP sensor structure width or height is defined according to the prior art by removing excess sensor material at opposite sides of the sensor structure to form voids to define the track width or stripe height. The photoresist used to protect the selected area of the sensor structure is lifted-off using the slurry.

1 . A method fabricating thin film magnetic heads on a wafer comprising the steps of: 
 patterning a photoresist over a predetermined position for a magnetic sensor on a thin film structure on the wafer;    forming a thin film structure for a magnetic sensor by removing excess material around the photoresist to form a void at a side of the thin film structure;    depositing a refill material over the wafer, the photoresist and into the void; and    removing the photoresist and the refill material deposited above the photoresist by a process which includes chemical-mechanical polishing (CMP) using a slurry with an a abrasive consisting of spherical particles less than 0.015 microns in size.    
     
     
         2 . The method of  claim 1  wherein the spherical particles are colloidal silica.  
     
     
         3 . The method of  claim 1  wherein the spherical particles are colloidal titania.  
     
     
         4 . The method of  claim 1  wherein the spherical particles are colloidal alumina.  
     
     
         5 . The method of  claim 1  wherein the spherical particles are colloidal zirconia.  
     
     
         6 . The method of  claim 1  wherein the slurry is alkaline.  
     
     
         7 . A method fabricating thin film magnetic heads on a wafer comprising the steps of: 
 patterning a photoresist over a predetermined position for a magnetic sensor structure;    forming the sensor structure width by removing excess sensor material around the photoresist at opposite sides of the sensor structure to form voids at first and second sides of the sensor structure;    depositing a dielectric material into the voids and over the photoresist;    depositing one or more layers for a hard bias structure into the voids onto the dielectric material;    depositing a selected material onto the hard bias structure;    depositing one or more layers for a CMP resistant mask over the selected material; and    removing the photoresist and all material deposited above the photoresist by a process which includes chemical-mechanical polishing (CMP) using a slurry with spherical particles less than 0.015 microns in size.    
     
     
         8 . The method of  claim 7  wherein the spherical particles are colloidal silica.  
     
     
         9 . The method of  claim 7  wherein the spherical particles are colloidal titania.  
     
     
         10 . The method of  claim 7  wherein the spherical particles are colloidal alumina.  
     
     
         11 . The method of  claim 7  wherein the spherical particles are colloidal zirconia.  
     
     
         12 . The method of  claim 7  wherein the slurry is alkaline.  
     
     
         13 . The method of  claim 7  wherein the step of depositing one or more layers for a CMP resistant mask further comprises depositing DLC.  
     
     
         14 . The method of  claim 7  wherein the step of depositing one or more layers for a CMP resistant mask further comprises depositing tantalum.  
     
     
         15 . The method of  claim 7  further comprising the step of fabricating a magnetic shield over the sensor structure after removing the photoresist.  
     
     
         16 . The method of  claim 7  wherein the selected material is a CMP resistant metal.  
     
     
         17 . The method of  claim 16  wherein the CMP resistant metal is selected from the group consisting of rhodium, chromium, vanadium and platinum.