Method for forming MTJ memory element

摘要

The present invention is directed to a method for forming a magnetic tunnel junction (MTJ) memory element comprising the steps of providing a substrate having a bottom electrode layer thereon; depositing an MTJ layer stack on top of the bottom electrode layer; forming a composite hard mask comprising a bottom conducting mask disposed on top of the MTJ layer stack and a top conducting mask with a dielectric mask interposed therebetween; etching the MTJ layer stack with the composite hard mask thereon to form a patterned MTJ while consuming the top conducting mask, thereby exposing the dielectric mask on top; and trimming the patterned MTJ with the bottom conducting mask and the dielectric mask thereon by ion beam etching to remove redeposited material and damaged material from surface of the patterned MTJ while consuming most of the dielectric mask.

主权项

1. A method for forming a magnetic tunnel junction (MTJ) memory element comprising the steps of:
providing a substrate having a bottom electrode layer thereon; depositing a MTJ layer stack on top of said bottom electrode layer; forming a composite hard mask comprising a bottom conducting mask disposed on top of said MTJ layer stack and a top conducting mask with a dielectric mask interposed therebetween; etching said MTJ layer stack with said composite hard mask thereon to form a patterned MTJ while consuming said top conducting mask, thereby exposing said dielectric mask on top; and trimming said patterned MTJ with said bottom conducting mask and said dielectric mask thereon by ion beam etching to remove redeposited material and damaged material from surface of said patterned MTJ while consuming most of said dielectric mask.