Patent ID: 8202572
Filing Date: 2012-06-19
Classification: B82Y,G11C,H01F,H01L

Abstract:
1. A method of forming a tunnel barrier in a magnetic tunnel junction (MTJ), comprising: (a) providing a substrate and subjecting said substrate to a natural oxidation process or to a plasma treatment with an inert gas; (b) depositing a first metal layer having a first thickness that forms a continuous film on the substrate; (c) performing a natural oxidation (NOX) process to convert said first metal layer to a first metal oxide (M (d) repeating the metal deposition and NOX process one or more times to form a stack including one or more metal oxide layers on the M (e) depositing an uppermost metal layer on the stack of one or more metal oxide layers wherein the uppermost metal layer has a thickness less than the thickness of the second metal layer; and (f) performing an annealing process that causes oxygen from the metal oxide layers to diffuse into the uppermost metal layer thereby fully oxidizing the uppermost M layer to an uppermost M