Micromachined unimorphs and bimorphs

A frequency doubled copper vapour laser (CVL) operating at an ultraviolet wavelength of 271 nm has been used to cut miniature cantilevers in laminated composites incorporating at least one layer of the ferroelectric polymer polyvinylidene fluoride (PVDF). Devices have been fabricated from PVDF with thickness values in the range 9 /spl mu/m to 38 /spl mu/m. Laser vibrometer measurements show that the fundamental resonance frequencies of these devices correspond almost exactly with values obtained from mechanical beam theory. Ultrasonic transducers consisting of bimorph and unimorph arrays are currently being designed with the aid of a finite element model, which is not discussed.