Pattern transfer with self-similar sacrificial mask layer and vector magnetic field sensor

Abstract

A method is provided for producing a lithographic pattern using a mask that includes the same materials as the material to be etched, allowing the pattern to be transferred and the etch mask to be removed in one step. In accordance with features of the invention, the method includes building up of a layer or layers of material of specific thickness on top of a substrate so that temporal control of an etching process allows formation of the desired pattern. Different exchange bias directions can be established by the use of shape anisotropy for the exchange biased component of a spin valve device. This enables several different magnetic reference directions to be present on a single chip, which allows a more compact magnetic field sensor to be developed. In accordance with features of the invention, different field directions are established on one single chip by using shape anisotropy

1 - 9 . (canceled)  
     
     
         10 . A vector magnetic field sensor for measuring an external magnetic field comprising: 
 a single chip; said single chip having different magnetic reference directions established; and    said different field directions being established on said single chip by using shape an isotropy.    
     
     
         11 . A vector magnetic field sensor as recited in  claim 10  wherein said single chip includes a free soft ferromagnetic layer.  
     
     
         12 . A vector magnetic field sensor as recited in claim  2  wherein said free layer includes a permalloy.  
     
     
         13 . A vector magnetic field sensor as recited in  claim 10  wherein said single chip includes a separating layer carried by a free layer.  
     
     
         14 . A vector magnetic field sensor as recited in  claim 13  wherein said separating layer includes a spin valve defined by a non-magnetic metal or tunnel junction defined by an insulator.  
     
     
         15 . A vector magnetic field sensor as recited in  claim 13  wherein said separating layer includes a tunnel junction defined by an insulator.  
     
     
         16 . A vector magnetic field sensor as recited in  claim 10  wherein said single chip includes a pinned ferromagnetic layer carried by a separating layer.  
     
     
         17 . A vector magnetic field sensor as recited in  claim 10  wherein said pinned layer includes a CoFe layer.  
     
     
         18 . A vector magnetic field sensor as recited in  claim 10  wherein said single chip includes a pinning layer carried by a pinned layer.  
     
     
         19 . A vector magnetic field sensor as recited in  claim 18  wherein said pinning layer includes a FeMn layer.