Highly reliable resistive memory cell and methods of forming the same

A method for preparing a resistive memory cell comprising:

• forming a resistive memory cell stack, comprising:
• depositing a bottom electrode layer over a substrate, wherein the bottom electrode layer comprises TiN, TaN, Ru, or combinations thereof;
• depositing a switching layer in contact with the bottom electrode layer in the presence of an oxygen containing gas;
• depositing a TaOx oxygen exchange layer in contact with the switching layer;
• depositing a top electrode layer over the TaOx oxygen exchange layer, wherein the top electrode layer is in contact with the TaOx oxygen exchange layer;
• and
• etching the resistive memory cell stack, comprising:
• performing an etching operation to form at least a portion of the resistive memory cell, wherein the etching operation is performed through a patterned hardmask layer positioned over the top electrode layer;
• oxidizing sidewalls of one or more layers within the resistive memory cell stack, wherein the sidewalls are formed during the etching operation;
• and
• forming an encapsulation layer over the at least a portion of the resistive memory cell.