Electric field assisted perpendicular stt-mram

Abstract

Present invention discloses a perpendicular STT-MRAM, a method of operating, and a method of manufacturing the same and a plurality of magnetoresistive memory elements having a recording layer which has an interface interaction with an underneath dielectric functional layer. The energy switch barrier of the recording layer is reduced under an electric field applying along a perpendicular direction of the functional with a proper voltage on a digital line from a control circuitry; accordingly, the perpendicular magnetization of the recording layer is readily reversible in a low spin-transfer switching current.

1 . A method of manufacturing a magnetoresistive memory element comprising
 making a digital line;   making a dielectric functional layer;   making a recording layer;   making a tunnel barrier layer;   making a reference layer;   making a cap layer;   making a middle electrode and a bit line; and   making a self-aligned patterning process to make the middle electrode electrically connected to the recording layer.   
     
     
         2 . The method of  claim 1 , wherein said digital line, said dielectric functional layer, said recording layer, said tunnel barrier layer, said reference layer, said cap layer are sequentially formed on the substrate, patterned using a lithography technique and a RIE process down to a bottom surface, and followed by a deposition of an insulating film on the entire surface and a chemical mechanical polishing (CMP) to flatten the upper surface. 
     
     
         3 . The method of  claim 1 , further comprising a patterning process having an end-point detection technique to etch down to middle of the tunnel barrier layer, followed by an optional process includes O ion or N ion implantation into the etched surface. 
     
     
         4 . The method of  claim 1 , further comprising a deposition of a conformal insulating film to cover entire patterned surface. 
     
     
         5 . The method of  claim 1 , further comprising an ion milling process normal to the substrate surface to etch away the insulating material on top surface of the conductive layer to form a self-aligned mask comprising a remaining top hard mask and sidewall insulating film. 
     
     
         6 . The method of  claim 1 , further comprising an ion milling process normal to the substrate surface having an end-point detection technique to etch down to middle of the recording layer. 
     
     
         7 . The method of  claim 1 , further comprising a deposition of a nonmagnetic metal layer by an IBD process having a deposition normal to the substrate surface. 
     
     
         8 . The method of  claim 1 , further comprising a rotating IBE process having a large angle to mill away the side wall metal layer. 
     
     
         9 . The method of  claim 1 , further comprising a deposition of an interlayer insulating film, a chemical mechanical polishing (CMP) to flatten upper face of the interlayer insulating film, followed by a bit line deposition and patterning.