DRY ETCH PATTERNING OF LACAMNO3 AND SMCO THIN-FILMS

A number of different plasma chemistries have been employed for patter ning of LaCaMnO3 and SmCo thin films for application in magnetic-field -biased structures based on the-colossal magnetoresistive effect. For LaCaMnO3 there was no chemical enhancement in etch rate over simple Ar sputtering for Cl-2, SF6, and CH4/H-2 plasmas under high ion density conditions. This is expected based on the vapor pressures of the prosp ective etch products. For SmCo, however, etch rates up to 7000 Angstro m min(-1) were obtained in Cl-2/Ar plasmas, which is an order of magni tude faster than Ar sputtering under the same experimental conditions. Smooth etched surface morphologies and anistropic sidewalls were obta ined for both materials over a wide range of plasma source and chuck p owers.