A Self Bias-flip Piezoelectric Energy Harvester Array without External Energy Reservoirs achieving 488% Improvement with 4-Ratio Switched-PEH DC-DC Converter

With the advent of the lnternet-of-Things (1oT) era, sensor nodes are required in almost all fields to achieve a better interaction between humans and the environment. Piezoelectric energy harvester (PEH), which exhibits an equivalent electrical model of an AC current source /P in parallel with the inherent capacitor CP, is a promising...

A novel method to transfer porous PDMS membranes for high throughput Organ-on-Chip and Lab-on-Chip assembly

We present a novel method to easily and reliably transfer highly porous, large area, thin microfabricated Polydimethylsiloxane (PDMS) porous membranes on Lab-on-Chip (LOC) and Organ-on-Chip (OOC) devices. The use of silicon as carrier substrate and a water-soluble sacrificial layer allows a simple and reproducible transfer of the membranes to...

A transfer-free wafer-scale CVD graphene fabrication process for MEMS/NEMS sensors

In this paper we report a novel transfer-free graphene fabrication process, which does not damage the graphene layer. Uniform graphene layers on 4" silicon wafers were deposited by chemical vapor deposition using the CMOS compatible Mo catalyst. Removal of the Mo layer after graphene deposition results in a transfer-free and controlled placement...

Characterization of low temperature deposited atomic layer deposition TiO2 for MEMS applications

TiO2 is an interesting and promising material for micro-/nanoelectromechanical systems (MEMS/NEMS). For high performance and reliable MEMS/NEMS, optimization of the optical characteristics, mechanical stress, and especially surface smoothness of TiO2 is required. To overcome the roughness issue of the TiO2 films due to crystallization during...

A piezo-thermal probe for thermomechanical analysis

Thermomechanical analysis (TMA) is widely used to characterize materials and determine transition temperatures and thermal expansion coefficients. Atomic-force microscopy (AFM) microcantilevers have been used for TMA. We have developed a micromachined probe that includes two embedded sensors: one for measuring the mechanical movement of the...

A colorimetric receptor combined with a microcantilever sensor for explosive vapor detection

Substantial effort has been devoted to the synthesis of molecular receptors that can function as chemosensors for nitroaromatic explosives. In spite of several advantages, these receptors suffer from low sensitivity and difficulties translating the response into the gas phase. We have combined tetrathiafulvalene-functionalized calix[4]pyrrole, a...

Mechanical stiffening, bistability, and bit operations in a microcantilever

We investigate the nonlinear dynamics of microcantilevers. We demonstrate mechanical stiffening of the frequency response at large amplitudes, originating from the geometric nonlinearity. At strong driving the cantilever amplitude is bistable. We map the bistable regime as a function of drive frequency and amplitude, and suggest several...

Buckling beam micromechanical memory with on-chip readout

We have used double clamped beams to implement a mechanical memory. Compressive stress is generated by resistive heating of the beams and beyond the buckling limit the bistable regime is accessed. Bits are written by applying lateral electrostatic forces. The state of the beam is read out by measuring the capacitance between beam and electrodes....

Magnetovibrational coupling in small cantilevers

A nanomagnetomechanical system consisting of a cantilever and a thin magnetic film is predicted to display magnetovibrational modes, which should enable applications for sensors and actuators. The “polaritonic” modes can be detected by line splittings in ferromagnetic resonance spectra.