I have also been responsible for designing, fabricating and testing a micromechanical silicon beam resonator in which the vibrations are driven and detected by thick-film printed piezoelectric elements. This work has been carried out to demonstrate the potential for depositing lead zirconate titanate (PZT) material using a thick-film printing process and combining this approach with silicon micromachining processes. The resonator was initially simulated using finite element analysis in order to maximise the degree of mechanical coupling and therefore excitation and detection efficiency. Standard micromachining steps and thick-film printing processes have been successfully combined to fabricate the device. The resonator is a fixed ends beam, 2mm long and 0.52mm wide, resonates in air and has a fundamental mode at 56.5kHz with a Q-factor of 70.
Figure 1 - Resonator design
Figure 2 - SEM photo of device
Figure 3 - Electrical response of resonator in air (blue) and vacuum (pink)