This paper reports results on ionic EAP micromuscles converting electrical into micromechanical response in open‐air. Translation of small ion motion into large deformation in bending microactuator and its amplification by fundamental resonant frequency are used as tools to demonstrate that small ion vibrations can still occur at frequency as high as 1000 Hz in electrochemical devices. These results are achieved through the microfabrication of ultrathin conducting polymer microactuators. First, the synthesis of robust interpenetrating polymer networks (IPNs) is combined with a spincoating technique in order to tune and drastically reduce the thickness of conducting IPN microactuators using a so‐called “trilayer” configuration. Patterning of electroactive materials as thin as 6 μm is demonstrated with existing technologies, such as standard photolithography and dry etching. Electrochemomechanical characterizations of the micrometer sized beams are presented and compared to existing model. Moreover, thanks to downscaling, large displacements under low voltage stimulation (±4 V) are reported at a frequency as high as 930 Hz corresponding to the fundamental eigenfrequency of the microbeam. Finally, conducting IPN microactuators are then presenting unprecedented combination of softness, low driving voltage, large displacement, and fast response speed, which are the keys for further development to develop new MEMS.

Interpenetrating polymer networks can become successful actuators in the field of microsystems providing they are compatible with microtechnologies. In this letter, we report on a material synthesized from poly͑3,4-ethylenedioxythiophene͒ and polytetrahydrofuran/poly͑ethylene oxide͒ and microsized by decreasing its thickness to 12 m and patterning the lateral side using plasma etching at high etch rates and with vertical sidewalls. A chemical process and a "self degradation" are proposed to explain such etching rates. Preliminary actuation results show that microbeams can move with very large displacements. These microsized actuators are potential candidates in numerous applications, including microswitches, microvalves, microoptical instrumentation, and microrobotics.

This paper presents a feasibility step in the development of an ultra-small biomimetic flying machine. Advanced engineering technologies available for applications such as the micro-electro-mechanical system (MEMS) technologies are used. To achieve this goal, a flapping-wing flying MEMS concept and design inspired from insects is first described. Actuators and an actuation way for the control over the wing kinematics are proposed. The initial concepts are subsequently analyzed and presented using multi-body and finite element models. An overview of SU-8 photoresist structures and their functions in the future micro-robot insect is then presented. Consequently, micromachining enables the implementation of a flying MEMS. It is also demonstrated that the structure can be made at insect sizes and actuated at low power inputs. Moreover, the flapping frequency obtained is within the flapping frequency range of wings of many common insects of millimetric dimensions. Such prototypes are of interest as tools to artificially recreate and study insect flight with characteristics, similar to those of insects, that are able to produce lift and hover. Finally, if a micro-battery, wireless receivers, microcontrollers, sensors and actuators can all be fitted onto chips only a few millimeters square, with a mass in the order of milligrams, then we believe that an insect-size flying MEMS can be realized. All these requirements can now be achieved due to advanced engineering methods.

The development of microsystems is a rapidly evolving field which enables a wide range of applications for electroactive materials. Microelectromechanical actuators based on electronically conducting polymers are elaborated with an up‐scalable process. Commercial poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) is chosen as an easily processable electrode to ensure the reproducibility for further technological production and practical applications. First, the improvement of electrical, electrochemical, and mechanical properties of the PEDOT:PSS electrodes is described by incorporating reactive additives, that is, glycol‐based monomers (mPEG) as polyethylene oxide (PEO) network precursors. Moreover, the custom fit layer‐by‐layer (LbL) process to integrate these PEDOT:PSS/PEO composite electrodes into trilayer microactuators is presented. The incorporation of PEO within PEDOT:PSS improves significantly the electromechanical performances of the resulting microactuators with significant strain (0.82%) and high output forces (472 µN) compared to similar PEDOT based or pristine PEDOT:PSS microactuators. This work provides also the first demonstration that mechanical strain sensing behavior, extensively studied at macroscale, still occurs at microscale for these trilayer systems. Additionally, to this proof of concept, it highlights that output signal is significantly enhanced by downsizing the devices compared to similar macroscale samples. These results open promising perspectives in the development of numerous applications for soft and scalable microactuators and microsensors.

Recent progress in the field of microsystems on flexible substrates raises the need for alternatives to the stiffness of classical actuation technologies. This paper reports a top-down process to microfabricate soft conducting polymer actuators on substrates on which they ultimately operate. The bending microactuators were fabricated by sequentially stacking layers using a layer polymerization by layer polymerization of conducting polymer electrodes and a solid polymer electrolyte. Standalone microbeams thinner than 10 μm were fabricated on SU-8 substrates associated with a bottom gold electrical contact. The operation of microactuators was demonstrated in air and at low voltage (±4 V).

No abstract

No abstract

Ion beam etching of sputtered Pb(Zr x ,Ti 1Ϫx )O 3 ͑PZT͒ with x equal to 0.54 thin films grown on Pt/Ti/SiO 2 /Si substrates has been performed using pure Ar gas. The etch rate dependence on the process parameters ͑current density, acceleration voltage, gas pressure͒ has been investigated. The PZT etch rate can reach 600 Å/min with acceleration voltage of 1000 V and current density of 1 mA/cm 2 . Selectivity ratios between PZT and masks of various natures ͑photoresist, Pt, Ti͒ have been evaluated to determine a pertinent material for etching mask. According to our etching conditions, titanium seems to be the best candidate. We evaluated the PZT surface damage by contact mode atomic force microscopy. It appears that the roughness increases after ion bombardment, and that the grain boundary zone is preferentially etched. For some etching parameters, we also observed electrical damage. Carrying out C(V) and hysteresis loops P(E) measurements before and after etching have provided evidence of degradation. We noted a large decrease in permittivity after the etching process irrespective of the current density and acceleration voltage. Ferroelectric damage was illustrated by a large increase in the average coercive field. For each of the electrical properties under study, the same behavior has been observed after etching: the increase of damage was obtained as a function of the current density and acceleration voltage. The evolution of electrical properties when the PZT layer is protected by a metallic mask has also been studied. We observed very slight variations in the electrical properties.