Reducing parasitic effects of actuation and sensing schemes for piezoelectric microelectromechanical resonators

Abstract

The co-integration of piezoelectric actuation and sensing capabilities on !+" microelectromechanical system-based resonators can be a source of electrical cross-talk that, if not !!" properly taken into account, may dramatically affect the interpretation of the device's output. In this !#" paper, we identify three parasitic electrical effects pertaining to the most commonly used piezoelectric !$" actuation and sensing schemes. To further investigate the impact of such parasitic effects, !%" microcantilevers, bridges and membranes integrating a layer of sol-gel lead zirconate titanate (PZT) !&" were fabricated and electrically characterized. Experimental results on the resonant characteristics !'" were compared with simulations of the studied resonators' equivalent electrical models. Methods for !(" reducing the design-dependent parasitic electrical effects such as mutual capacitances of less than !)" 10fF, electrical wiring or static capacitance mismatches of less than 20% of the integrated !*" piezoelectric films are discussed. #+" #!" ##" The on-chip actuation and sensing schemes studied in this paper along with the use of dedicated %)" electronics developed for this purpose aim to answer these questions. A series of design rules for %*" piezoelectric materials integration is proposed from the standpoint of MEMS-based resonator &+" development.

Efficient parametric amplification in micro-resonators with integrated piezoelectric actuation and sensing capabilities

“…The fabrication process has been detailed elsewhere. 21 When electrically actuated, the piezoelectric elements attempt to contract laterally in proportion to the applied voltage V(t). The mechanical action on the beam is equivalent to a concentrated moment and an axial force applied at the end of the piezoelectric element 22 ( Fig.…”

Piezoelectric nanoelectromechanical systems integrating microcontact printed lead zirconate titanate films

“…A schematic of the apparatus used for resonance frequency measurements [16,20] is shown in figure 4. To operate the device, a sinusoidal voltage V 1 was applied between the top and bottom electrodes on the piezoelectric layer, leading to the motion of free-standing cantilevers due to the converse piezoelectric effect.…”

“…[9][10][11][12][13][14][15][16][17][18][19][20][21] Of the various transduction mechanisms used in MEMS devices, piezoelectricity requires relatively low actuation voltage and offers the possibility of sensing, resulting in integrated devices that are compact, and thus potentially portable. [13][14][15][16]20,21 In this regard, piezoelectric films could be particularly advantageous for transduction in NEMS, since there are few solutions suited to both actuation and sensing at this scale. However, studies have shown that some sputtered PZT films on NEMS resonators displayed reduced performance, 17,18 likely as a result of a deterioration of the films' piezoelectric characteristics with reduced thickness.…”

“…Piezoelectric films, which translate mechanical energy into electrical and vice versa, have widely been used for microelectromechanical systems (MEMS) transduction, i.e. actuation and detection [9][10][11][12][13][14][15][16][17][18][19][20][21]. Of the various transduction mechanisms used in MEMS devices, piezoelectricity requires relatively low actuation voltage and offers the possibility of sensing, resulting in integrated devices that are compact, and thus potentially portable [13-16, 20, 21].…”

Fabrication and characterization of mechanical resonators integrating microcontact printed PZT films

“…So far, piezoelectric films, which translate mechanical energy into electrical and vice-versa, have already been widely used for microelectromechanical systems (MEMS) transduction [5] [6]. Piezoelectrics require relatively low actuation voltage and also offer a sensing capability, resulting in devices that are compact, thus potentially portable.…”