Effect of droplet shrinking on surface acoustic wave response in microfluidic applications

The effect of the contact angle and radius of a microsize droplet on the surface acoustic wave (SAW) response for microfluidic applications is reported. It is studied through the dynamic change of the droplet shape during the evaporation process. An aluminium nitride SAW device, operating at 125.7 MHz, is utilized to investigate the...

Liquid identification by using a micro-electro-mechanical interdigital transducer

A surface-acoustic-mode aluminum nitride (AlN) transducer is utilized to determine the type of liquid dropped on the propagation path. It is based on tracking the shrinking droplet radius and observing stagnant liquid molecules during and after the liquid evaporation process. The device configuration is suitable to test small amounts of...

Finite element modelling and experimental characterization of an electro-thermally actuated silicon-polymer micro gripper

Polymer constraint effect for electrothermal bimorph microactuators

The authors report on the analysis of the polymer constraint effect and its use for a micromachined electrothermal bimorph actuator. The actuated displacement is enhanced due to the polymer constraint effect. Both the thermal expansion and apparent Young’s modulus of the constrained polymer blocks are significantly improved, compared with the no...

Powerful polymeric thermal microactuator with embedded silicon microstructure

A powerful and effective design of a polymeric thermal microactuator is presented. The design has SU-8 epoxy layers filled and bonded in a meandering silicon (Si) microstructure. The silicon microstructure reinforces the SU-8 layers by lateral restraint. It also improves the transverse thermal expansion coefficient and heat transfer for the...

An in-plane thermal unimorph using confined polymers