One-mask mtj integration for stt mram

Abstract

A method for integrating a magnetic tunnel junction (MTJ) device into an integrated circuit includes providing in a semiconductor back-end-of-line (BEOL) process flow a substrate having a first interlevel dielectric layer and at least a first conductive interconnect. Over the first interlevel dielectric layer and the first conductive interconnect, magnetic tunnel junction material layers are deposited. From the material layers a magnetic tunnel junction stack, coupled to the first conductive interconnect, is defined using a single mask process. The magnetic tunnel junction stack is integrated into the integrated circuit.

What is claimed is: 
     
         1 . A magnetic tunnel junction (MTJ) device in an integrated circuit (IC), comprising:
 a substrate comprising a first interlevel dielectric layer and a first conductive interconnect; and   a magnetic tunnel junction stack communicating with the first conductive interconnect, the magnetic tunnel junction stack comprising a plurality of magnetic tunnel junction material layers directly on the first interlevel dielectric layer and the first conductive interconnect, the magnetic tunnel junction stack having been defined from all of the plurality of magnetic tunnel junction material layers using only a single mask process, wherein the magnetic tunnel device is integrated into the IC.   
     
     
         2 . The MTJ device of  claim 1 , wherein the magnetic tunnel junction stack comprises:
 a first electrode layer directly on the first conductive interconnect and on the first interlevel dielectric layer;   the plurality of magnetic tunnel junction layers on the first electrode layer; and   a second electrode on the magnetic tunnel junction layers.   
     
     
         3 . The MTJ device of  claim 2 , wherein the magnetic tunnel junction layers comprise:
 a fixed magnetization layer;   a tunnel barrier layer; and   a free magnetization layer.   
     
     
         4 . The MTJ device of  claim 2 , further comprising:
 a first dielectric passivation barrier layer on the magnetic tunnel junction stack and directly on the first interlevel dielectric layer; and   a second interlevel dielectric layer on the first dielectric passivation barrier layer, the second interlevel dielectric layer and the first dielectric passivation barrier layer exposing the second electrode of the magnetic tunnel junction stack.   
     
     
         5 . The MTJ device of  claim 4 , further comprising:
 a second dielectric passivation barrier layer on the second interlevel dielectric layer and the second electrode;   a third interlevel dielectric layer on the second dielectric passivation barrier layer; and   a second conductive interconnect in the third interlevel dielectric layer and the second dielectric passivation barrier layer, the second conductive interconnect being in communication with the second electrode.   
     
     
         6 . The MTJ device of  claim 5 , further comprising:
 a third conductive interconnect in the first interlevel dielectric layer;   a conductive via in the second interlevel dielectric layer and the first dielectric passivation barrier layer, the conductive via being in communication with the third conductive interconnect; and   a fourth conductive interconnect in the third interlevel dielectric layer and the second dielectric passivation barrier layer, the fourth conductive interconnect being in communication with the conductive via.   
     
     
         7 . The MTJ device of  claim 1 , further comprising a barrier layer between a first interlevel dielectric of the substrate and the magnetic tunnel junction stack. 
     
     
         8 . The MTJ device of  claim 1 , wherein the MTJ device is incorporated in a device selected from the group consisting of a mobile phone, personal data assistant (PDA), navigation device, fixed location data unit, set-top box, music player, video player, entertainment unit, and computer. 
     
     
         9 . A magnetic tunnel junction (MTJ) structure, comprising:
 a substrate comprising a first interlevel dielectric layer and a first conductive interconnect; and   means for communicating with the first conductive interconnect, the means for communicating with the first conductive interconnect comprising a plurality of magnetic tunnel junction material layers directly on the first interlevel dielectric layer and the first conductive interconnect, the communicating means defined from all of the plurality of magnetic tunnel junction material layers using only a single mask process.   
     
     
         10 . The MTJ structure of  claim 9 , wherein the communicating means comprises a magnetic tunnel junction stack comprising:
 a first electrode layer directly on the first conductive interconnect and on the first interlevel dielectric layer;   the plurality of magnetic tunnel junction layers on the first electrode layer; and   a second electrode layer on the magnetic tunnel junction layers.   
     
     
         11 . The MTJ structure of  claim 10 , wherein the magnetic tunnel junction layers comprise:
 a fixed magnetization layer;   a tunnel barrier layer; and   a free magnetization layer.   
     
     
         12 . The MTJ structure of  claim 10 , further comprising:
 a first dielectric passivation barrier layer on the magnetic tunnel junction stack and directly on the first interlevel dielectric layer; and   a second interlevel dielectric layer on the first dielectric passivation barrier layer, the second interlevel dielectric layer and the first dielectric passivation barrier layer exposing the second electrode layer of the magnetic tunnel junction stack.   
     
     
         13 . The MTJ structure of  claim 12 , further comprising:
 a second dielectric passivation barrier layer on the second interlevel dielectric layer and the second electrode layer;   a third interlevel dielectric layer on the second dielectric passivation barrier layer; and   a second conductive interconnect in the third interlevel dielectric layer and the second dielectric passivation barrier layer, the second conductive interconnect in communication with the second electrode layer.   
     
     
         14 . The MTJ structure of  claim 13 , further comprising:
 a third conductive interconnect in the first interlevel dielectric layer;   a conductive via in the second interlevel dielectric layer and the first dielectric passivation barrier layer, the conductive via being in communication with the third conductive interconnect; and   a fourth conductive interconnect in the third interlevel dielectric layer and the second dielectric passivation barrier layer, the fourth conductive interconnect being in communication with the conductive via.   
     
     
         15 . The MTJ structure of  claim 9 , further comprising a barrier layer between a first interlevel dielectric of the substrate and the means for communicating. 
     
     
         16 . The MTJ structure of  claim 10  in which the first electrode layer and the second electrode layer have a same lateral dimension as the magnetic tunnel junction stack based upon a first mask. 
     
     
         17 . The MTJ structure of  claim 16 , integrated into a spin-torque-transfer (STT) MRAM. 
     
     
         18 . The MTJ structure of  claim 17 , in which the STT MRAM is coupled to a microprocessor. 
     
     
         19 . The MTJ structure of  claim 17 , in which the STT MRAM is integrated into a device selected from the group consisting of a set top box, music player, video player, entertainment unit, navigation device, communications device, personal digital assistant (PDA), fixed location data unit, microprocessor, and a computer. 
     
     
         20 . The MTJ structure of  claim 9 , incorporated in a device selected from the group consisting of a mobile phone, personal data assistant (PDA), navigation device, fixed location data unit, set-top box, music player, video player, entertainment unit, and computer. 
     
     
         21 . A magnetic tunnel junction (MTJ) structure, comprising:
 a first conductive interconnect arranged to couple with at least one control device;   a first electrode layer on the first conductive interconnect;   a magnetic tunnel junction stack comprising a plurality of magnetic tunnel junction material layers on the first electrode layer;   a second electrode layer on the magnetic tunnel junction stack, the first electrode layer and the second electrode layer having a same lateral dimension as the magnetic tunnel junction stack based upon a first mask; and   a second conductive interconnect on the second electrode layer and arranged to couple with at least one other control device.   
     
     
         22 . The MTJ structure of  claim 21 , integrated into a spin-torque-transfer (STT) magnetic random access memory (MRAM). 
     
     
         23 . The MTJ structure of  claim 22 , in which the STT MRAM is coupled to a microprocessor. 
     
     
         24 . The MTJ structure of  claim 22 , in which the STT MRAM is integrated into a device selected from the group consisting of a set top box, music player, video player, entertainment unit, navigation device, communications device, personal digital assistant (PDA), fixed location data unit, microprocessor, and a computer. 
     
     
         25 . A magnetic tunnel junction (MTJ) structure, comprising:
 a first interconnect means for communicating with at least one control device;   a first electrode means for coupling to the first interconnect means;   an MTJ means for storing data, the MTJ means coupling to the first electrode means;   a second electrode means for coupling to the MTJ means, the first and second electrode means having a same lateral dimension as the MTJ means based upon a first mask; and   a second interconnect means for coupling to the second electrode means and at least one other control device.   
     
     
         26 . The MTJ structure of  claim 25 , integrated into a spin-torque-transfer (STT) MRAM. 
     
     
         27 . The MTJ structure of  claim 26 , in which the STT MRAM is coupled to a microprocessor. 
     
     
         28 . The MTJ structure of  claim 26 , in which the STT MRAM is integrated into a device selected from the group consisting of a set top box, music player, video player, entertainment unit, navigation device, communications device, personal digital assistant (PDA), fixed location data unit, microprocessor, and a computer.