Magnetic sensor manufacturing

Abstract

A magnetic sensor comprising a first shield and a second shield and a sensor stack between the first and the second shield, the sensor stack having a plurality of layers wherein at least one layer is annealed using in-situ rapid thermal annealing. In one implementation of the magnetic sensor a seed layer is annealed using in-situ rapid thermal annealing. Alternatively, one of a barrier layer, an antiferromagnetic (AFM) layer, and a cap layer is annealed using in-situ rapid thermal annealing.

1 .- 6 . (canceled) 
     
     
         7 . A reader head fabrication assembly comprising:
 a sensor stack tool; and   an in-situ rapid anneal module docked onto the sensor stack tool and configured to:
 individually anneal select layers of a sensor stack after deposition of each select layer during a stack deposition sequence, the select layers including: 
 an MgO barrier layer, the MgO barrier layer undergoing the following steps:
 1) depositing the MgO barrier layer; 
 2) annealing the deposited MgO barrier layer; and 
 3) cryo-cooling the annealed MgO barrier layer. 
 
   
     
     
         8 . The reader head fabrication assembly of  claim 7 , wherein the sensor stack includes an additional layer deposited on the MgO barrier layer, and a cap layer deposited on the sensor stack. 
     
     
         9 . The reader head fabrication assembly of  claim 7 , wherein sensor stack further includes a seed layer, the seed layer annealed after deposition. 
     
     
         10 . The reader head fabrication assembly of  claim 9 , wherein sensor stack further includes an AFM layer deposited on the annealed seed layer, the AFM layer annealed after deposition. 
     
     
         11 . The reader head fabrication assembly of  claim 10 , wherein the sensor stack further includes a SAF layer deposited on the annealed AFM layer. 
     
     
         12 . The reader head fabrication assembly of  claim 11 , wherein the MgO barrier layer is deposited on the SAF layer. 
     
     
         13 . A method, comprising:
 annealing individually during a sensor stack deposition sequence at least two layers using in-situ rapid thermal annealing after each of the at least two layers of the sensor stack is deposited, wherein one of the annealed layers is an MgO barrier layer and wherein one of the annealed layers is an antiferromagnetic (AFM) layer; and   cryo-cooling the MgO barrier layer after the MgO barrier layer is annealed and before additional layers are deposited on the MgO barrier layer.   
     
     
         14 . The method of  claim 13 , wherein depositing the MgO barrier layer further comprises depositing the MgO barrier layer at a temperature within a range of 200 to 400 degrees centigrade. 
     
     
         15 . The method of  claim 13 , further comprising:
 annealing individually at least two layers of the sensor stack with an in-situ rapid anneal module docked onto a sensor stack tool.   
     
     
         16 . The method of  claim 15 , further comprising:
 depositing an AFM layer; and   annealing the AFM layer.   
     
     
         17 . The method of  claim 16 , further comprising:
 depositing a CoFe pinning layer on top of the annealed AFM layer; and   annealing the CoFe pinning layer.   
     
     
         18 . The method of  claim 16 , further comprising:
 depositing an SAF layer on top of the annealed AFM layer.   
     
     
         19 . The method of  claim 18 , further comprising:
 depositing a free layer on top of the SAF layer; and   depositing a cap layer on top of the free layer.   
     
     
         20 . The method of  claim 18 , further comprising:
 depositing a metallic spacer layer on top of the SAF layer;   annealing the metallic spacer layer using in-situ thermal annealing; and   cryo cooling the annealed metallic spacer layer.