Methods (100) are provided for fabricating a ferroelectric capacitor structure including methods (128) for etching and cleaning patterned ferroelectric capacitor structures in a semiconductor device. The methods comprise etching (140, 200) portions of an upper electrode, etching (141, 201) ferroelectric material, and etching (142, 202) a lower electrode to define a patterned ferroelectric capacitor structure, and etching (143, 206) a portion of a lower electrode diffusion barrier structure. The methods further comprise ashing (144, 203) the patterned ferroelectric capacitor structure using a first ashing process, performing (145, 204) a wet clean process after the first ashing process, and ashing (146, 205) the patterned ferroelectric capacitor structure using a second ashing process directly after the wet clean process at a high temperature in an oxidizing ambient.