Piezo-electric AlN and PZT films for micro-electronic applications

Piezoelectric AlN and PbZr/sub x/Ti/sub 1-x/O/sub 3/ (PZT) layers are investigated with respect to their potential for HF micro-electronic applications. High quality AlN films with strong c-axis orientation are achieved by optimum deposition conditions and by applying nucleation layers. Electromechanical coupling factors of 0.25/spl plusmn/0.03 have been found. PZT films grown via sol-gel processing show high coupling factors k of 0.4-0.6 and are therefore attractive for wide bandwidth applications.