Patent ID: 7169637

Claim:
A one-mask etching method for use with a perovskite-containing RRAM to reduce stack side-wall residuals, comprising: preparing a substrate; depositing a bottom electrode on the substrate; depositing a perovskite layer on the bottom electrode; depositing a top electrode on the perovskite layer; depositing a hard mask on the top electrode; depositing and patterning a photoresist layer on the hard mask; etching the hard mask; etching the top electrode using a first etching process having an etching atmosphere consisting of Ar, O 2 , and Cl 2 ; etching the perovskite layer using an etching process taken from the group of etching processes consisting of the first etching process and a second etching process having an etching atmosphere consisting of Ar and O 2 ; etching the bottom electrode using the first etching process; and completing the RRAM device.