Patent ID: 7250349

Claim:
A method for forming a ferroelectric capacitor comprising: providing a dielectric layer over a semiconductor; forming a barrier layer over said dielectric layer; forming a first metal layer over said barrier layer; forming a ferroelectric layer over said first metal layer; forming a hard-mask layer over said second metal layer; and etching said second metal layer, said ferroelectric layer, and said first metal layer using a three step plasma process comprising: a first metal layer etch comprising the gases Cl2, O2, N2, and CO; a PZT etch comprising the gases BCl3 and Cl2; and a second metal layer etch comprising the gases Cl2, O2, N2, and CO, wherein said plasma process comprises a PZT etch process comprising the gases BCl3 and Cl2 in a range of ratios from 1:4 to 10:1 respectively.