ETCHING EFFECTS ON FERROELECTRIC CAPACITORS WITH MULTILAYERED ELECTRODES

Dry etching of PZT thin film capacitors with RuOx/Pt multilayered elec trodes was studied to examine the etching effects. PZT films were depo sited on RuOx/Pt/Ti/SiO2/Si substrates by sol-gel process and Pt films were prepared by DC magnetron sputtering. PZT and Pt thin films were etched with Cl-2/C2F6/Ar gas combination in an Inductively Coupled Pla sma (ICP) by varying the etching parameters such as coil RF power, DC bias to wafer susceptor, and gas pressure. Etching effects were invest igated in terms of etch rate, etch selectivity, etch profiles, and ele ctrical properties of etched capacitors. Quantitative analysis of the etching damage was obtained by calculating the shift of the coercive f ield and the switchable polarization in hysteresis loops. Finally, the etching damage mechanism was discussed and the optimization of etchin g processes for the fabrication of PZT capacitors was attempted to min imize the etching damage to ferroelectric capacitors.