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Microelectromechanical Systems, Journal of

Issue 5 • Date Oct. 2008

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Displaying Results 1 - 25 of 28
  • Table of contents

    Page(s): C1 - C4
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    Freely Available from IEEE
  • Journal of Microelectromechanical Systems publication information

    Page(s): C2
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  • Energy Harvesters Driven by Broadband Random Vibrations

    Page(s): 1061 - 1071
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    Simple analytical models have proved very useful in understanding vibration energy harvesters driven by a sinusoidal acceleration. Corresponding analyses for broadband excitations have been absent. In this paper, we present new closed-form results on the output power, proof mass displacement, and optimal load of linear resonant energy harvesters driven by broadband vibrations. Output power dependence on signal bandwidth is also considered. The results are compared with those that are already well established for a sinusoidal acceleration. We formulate a stochastic description of more general energy-harvester models and show that the influence of elastic mechanical stoppers on the output power is dependent on the electrical load for large amplitude vibrations. View full abstract»

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  • Voltage Control of the Resonance Frequency of Dielectric Electroactive Polymer (DEAP) Membranes

    Page(s): 1072 - 1081
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    We report on the characterization, active tuning, and modeling of the first mode resonance frequency of dielectric electroactive polymer (DEAP) membranes. Unlike other resonance frequency tuning techniques, the tuning procedure presented here requires no external actuators or variable elements. Compliant electrodes were sputtered or implanted on both sides of 20-35-mum-thick and 2-4-mm-diameter polydimethylsiloxane membranes. The electrostatic force from an applied voltage adds compressive stress to the membrane, effectively softening the device and reducing its resonance frequency, in principle to zero at the buckling threshold. A reduction in resonance frequency up to 77% (limited by dielectric breakdown) from the initial value of 1620 Hz was observed at 1800 V for ion-implanted membranes. Excellent agreement was found between our measurements and an analytical model we developed based on the Rayleigh-Ritz theory. This model is more accurate in the tensile domain than the existing model for thick plates applied to DEAPs. By varying the resonance frequency of the membranes (and, hence, their compliance), they can be used as frequency-tunable attenuators. The same technology could also allow the fine-tuning of the resonance frequencies in the megahertz range of devices made from much stiffer polymers. View full abstract»

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  • Snap-Action Bistable Micromechanisms Actuated by Nonlinear Resonance

    Page(s): 1082 - 1093
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    This paper presents analysis, design, realization, and experimental demonstration of a bistable switch actuated dynamically utilizing mechanical resonance phenomenon. We demonstrated that if a bistable structure is driven into a resonance near one of its states, it may achieve a large enough amplitude of vibration, sufficient to switch between its stable states. Using energy analysis, we concluded that dynamic switching of bistable structures may provide significant energy advantages over conventional static-switching approaches. To confirm the results, we derived analytically the closed-form actuation conditions guaranteeing switching between the states of a bistable structure and applied these conditions to experimental devices. Micromachined prototypes of dynamically actuated bistable switches were designed, fabricated, and characterized. We demonstrated experimentally that resonant dynamic switching provides energy saving of around 60% at atmospheric pressure with proportional increase in efficiency as the pressure decreases. View full abstract»

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  • Phase-Change Materials in Optically Triggered Microactuators

    Page(s): 1094 - 1103
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    Phase-change materials have been extensively used for optical data storage in commercial rewritable compact disks and digital video disks. These materials are also widely considered for next-generation phase-change random access memories to replace current Flash memories. We suggest a different application of phase-change materials in optically triggered microactuators. The suggested device consists of a thin film of a phase-change material deposited on a microfabricated cantilever. A laser-induced phase transformation in the film initiates a cantilever deflection since the transformation is accompanied by a large density change. We analyze quantitative criteria for material selection and optimization of device dimensions for the largest possible actuation angles and deflections. The resulting analytical model is both verified numerically and applied experimentally. Furthermore, we show that these cantilevers offer a convenient way to measure film stresses and film strains associated with laser-induced phase transformations. View full abstract»

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  • Row/Column Addressing Scheme for Large Electrostatic Actuator MEMS Switch Arrays and Optimization of the Operational Reliability by Statistical Analysis

    Page(s): 1104 - 1113
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    This paper investigates the design and optimization of a row/column addressing scheme to individually pull in or pull out single electrostatic actuators in an N2 array, utilizing the electromechanical hysteresis behavior of electrostatic actuators and efficiently reducing the number of necessary control lines from N2 complexity to 27 V. This paper illustrates the principle of the row/column addressing scheme. Furthermore, it investigates the optimal addressing voltages to individually pull in or pull out single actuators with maximum operational reliability, determined by the statistical parameters of the pull-in and pull-out characteristics of the actuators. The investigated addressing scheme is implemented for the individual addressing of cross-connect switches in a microelectromechanical systems 20 X 20 switch array, which is utilized for the automated any-to-any interconnection of 20 input signal line pairs to 20 output signal line pairs. The investigated addressing scheme and the presented calculations were successfully tested on electrostatic actuators in a fabricated 20 X 20 array. The actuation voltages and their statistical variations were characterized for different subarray cluster sizes. Finally, the addressing voltages were calculated and verified by tests, resulting in an operational reliability of 99.9498% (502 parts per million (ppm) failure rate) for a 20 X 20 switch array and of 99.99982% (1.75 ppm failure rate) for a 3 X 3 subarray cluster. The array operates by AC-actuation voltage to minimize the disturbing effects by dielectric charging of the actuator isolation layers, as observed in this paper for DC-actuation voltages. View full abstract»

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  • Toward Flexible Thermoelectric Flow Sensors: A New Technological Approach

    Page(s): 1114 - 1119
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    A new technological approach on thin flexible sensors is presented. As proof of concept, a thermoelectric flow sensor on a 10-mum-thick polyimide foil has been realized. The advantages of silicon as a thermoelectric material and the stability of low-pressure chemical vapor deposition (LPCVD)-silicon nitride as a protective coating are combined with the flexibility of polymer substrates. The thermoelectric flow sensor is fabricated on a standard silicon wafer for handling purposes. Only the functional layers that are embedded in 600 nm of LPCVD-silicon nitride are transferred onto a 10-mum-thick polyimide. The bulk silicon has been removed using deep reactive ion etching. Samples have been fabricated and tested, proving the potential of this new technological concept. The first characterization results show that the sensor layout has to be adapted to the properties of the polymer substrate. View full abstract»

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  • Fracture Properties of LPCVD Silicon Nitride and Thermally Grown Silicon Oxide Thin Films From the Load-Deflection of Long \hbox {Si}_{3}\hbox {N}_{4} and \hbox {SiO}_{2}/\hbox {Si}_{3}\hbox {N}_{4} Diaphragms

    Page(s): 1120 - 1134
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    The bulge test is successfully extended to the determination of the fracture properties of silicon nitride and oxide thin films. This is achieved by using long diaphragms made of silicon nitride single layers and oxide/nitride bilayers, and applying a comprehensive mechanical model that describes the mechanical response of the diaphragms under uniform differential pressure. The model is valid for thin films with arbitrary z-dependent plane-strain modulus and prestress, where z denotes the coordinate perpendicular to the diaphragm. It takes into account the bending rigidity and stretching stiffness of the layered materials and the compliance of the supporting edges. This enables the accurate computation of the load-deflection response and stress distribution throughout the composite diaphragm as a function of the load, in particular at the critical pressure leading to the fracture of the diaphragms. The method is applied to diaphragms made of single layers of 300-nm-thick silicon nitride deposited by low- pressure chemical vapor deposition and composite diaphragms of silicon nitride grown on top of thermal silicon oxide films produced by wet thermal oxidation at 950degC and 1050degC with target thicknesses of 500, 750, and 1000 nm. All films characterized have an amorphous structure. Plane-strain moduli Eps and prestress levels sigma0 of 304.8 plusmn 12.2 GPa and 1132.3 plusmn 34.4 MPa, respectively, are extracted for Si3N4, whereas Eps = 49.1 plusmn 7.4 GPa and sigma0 = -258.6 plusmn 23.1 MPa are obtained for SiO2 films. The fracture data are analyzed using the standardized form of the Weibull distribution. The Si3N4 films present relatively high values of maximum stress at fracture and Weibull moduli, i.e., sigmamax = 7.89 plusmn 0.23 GPa and m = 50.0 plusmn 3.6, respectively, when compared to the thermal oxides (sigmamax = 0.890 plusmn 0.07 GPa - - and m = 12.1 plusmn 0.5 for 507-nm-thick 950degC layers). A marginal decrease of sigmamax with thickness is observed for SiO2, with no significant differences between the films grown at 950degC and 1050degC. Weibull moduli of oxide thin films are found to lie between 4.5 plusmn 1.2 and 19.8 plusmn 4.2, depending on the oxidation temperature and film thickness. View full abstract»

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  • Brownian Microscopy for Simultaneous In Situ Measurements of the Viscosity and Velocity Fields in Steady Laminar Microchannel Flows

    Page(s): 1135 - 1143
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    Brownian microscopy is an intriguing technique that enables in situ determination of the local fluid properties and velocity fields in microfluidic devices. We report application of Brownian microscopy to steady laminar microchannel flows and demonstrate accurate measurements of the viscosity of glycerin/water mixtures, as well as the velocity profiles. A theoretical model is developed to evaluate statistical errors in the measured Brownian diffusivity while accounting for complications associated with the electronic noise and finite exposure time of an imaging system. The model is validated using both Monte Carlo simulations and experiments. View full abstract»

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  • Micron-Scale Friction and Sliding Wear of Polycrystalline Silicon Thin Structural Films in Ambient Air

    Page(s): 1144 - 1154
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    Micron-scale static friction and wear coefficients, surface roughness, and resulting wear debris have been studied for sliding wear in polycrystalline silicon in ambient air at micro- Newton normal loads using on-chip sidewall test specimens, fabricated with the Sandia SUMMiT VTM process. With increasing number of wear cycles friction coefficients increased by a factor of two up to a steady-state regime, concomitant with a decay (after an initial sharp increase) in the wear coefficients and roughness. Wear coefficients were orders of magnitude smaller than reported macroscale values, suggesting that the wear resistance is higher at micrometer dimensions. Based on our observations, a sequence of micron-scale wear mechanisms is proposed involving: 1) a short adhesive wear regime (< 104 cycles), where the oxide is worn away and the first silicon debris particles form and 2) a regime dominated by abrasive wear, where silicon particles (50-100 nm) are created by fracture through the grains (~500 nm). These particles subsequently oxidize and agglomerate into larger debris clusters, while "ploughing" by this debris leads to abrasive grooves associated with local cracking events rather than plastic deformation. View full abstract»

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  • Characterization of Deformation Behaviors and Elastic Moduli of Multilayered Films in Piezoelectric Inkjet Head

    Page(s): 1155 - 1163
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    A bulge testing system was developed to mechanically characterize the deformation behaviors and elastic moduli of multilayered films, mainly composed of polycrystalline silicon (polysilicon) and lead zirconate titanate (PZT), used in a multilayer actuator of a piezoelectric inkjet head. In the tests, commercial inkjet heads including a few tens of multilayer actuators were directly pressurized by air, and the corresponding deflections were measured via full-field optical measurement techniques. An analytic solution derived from a thin-plate theory and finite-element analysis were used to describe pressure-deflection behaviors of films, and the results were compared with the experimental data to evaluate the elastic modulus of individual film. The results showed that the elastic moduli of polysilicon and PZT films are ~110 and ~49 GPa, respectively. These values were consistent with the nanoindentation results. For polysilicon films, about 30% reduction in elastic modulus, compared with that calculated from single-crystal elastic constants, was observed, and this was most likely attributed to the presence of microdefects like voids and microcracks at grain boundaries between columnar grains. View full abstract»

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  • Combdrive Configuration for an Electromagnetic Reluctance Actuator

    Page(s): 1164 - 1171
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    This paper presents a novel combdrive configuration of a linear magnetic microactuator. We discuss in detail the influence of the air-gap geometry on the plunger motion and give design rules to avoid pull-in behavior. This analysis results in a new configuration, which is, so far, only known for electrostatic actuators. The magnetic flux is guided over several interdigitating comb structures with moderate large gap width of 25 mum instead of one single plunger, as reported for earlier designs. This results in larger forces, scaling with the number of comb fingers, until the material reaches saturation. The new configuration linearizes the characteristics and saves driving power without sacrificing fabrication stability, which would arise from small air-gap widths. Several combdrive actuators featuring one, two, and eight comb fingers were fabricated in LIGA technology, simulated, and tested. For a driving current of 40 mA, the achievable stroke is measured to increase by 800% for eight comb fingers in comparison to one finger. Alternatively, for a given stroke, a reduction of the driving current of more than 50% is measured. View full abstract»

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  • A Polymeric Paraffin Microactuator

    Page(s): 1172 - 1177
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    Paraffin wax is a promising material in microactuators not only because of its ability of producing large displacements and high forces at the same time but also because of the variety of manufacturing techniques available. In this paper, a simple actuator based on paraffin wax as the active material is fabricated and tested. Ultraviolet-curable epoxy is used in a technique combining simultaneous moulding and liquid-phase photopolymerization in a single-process step to build the stiff part of the actuator body. A heater is integrated in the paraffin reservoir, and a polyimide tape is used as the deflecting membrane. Thermomechanical analysis of the paraffin wax shows that it exhibits a volume expansion of 10%, including phase transitions and linear expansion. As for the actuator, a stroke of 90 mum is obtained for the unloaded device, whereas 37 mum is recorded with a 0.5-N contact load at a driving voltage of 0.71 V and a frequency of 1/32 Hz. The actuator can be used in microsystems, where both large strokes and forces are needed. The low-cost materials and low driving voltage also makes it suitable for disposable systems. View full abstract»

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  • Flexible Polymer Sensors for In Vivo Intravascular Shear Stress Analysis

    Page(s): 1178 - 1186
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    Hemodynamic forces, specifically fluid shear stress, play an important role in the focal nature of arterial plaque formation known as atherosclerosis. We hereby developed biocompatible and flexible intravascular microelectromechanical systems sensor to measure real-time shear stress in the aortas of New Zealand white (NZW) rabbits. Titanium (Ti) and platinum (Pt) were deposited on silicon wafers and patterned to form the sensing elements. The polymer, parylene C, provided insulation to the electrode leads and flexibility to the sensors. Based on heat transfer principle, the heat dissipation from the sensors to the blood flow altered the resistance of the sensing elements, from which shear stress was calibrated. The resistance of the sensing element was measured at approximately 1.0 kOmega , and the temperature coefficient of resistance was at approximately 0.16%/degC. The individual sensors were packaged to the catheter for intravascular deployment in the aortas of NZW rabbits (n = 5) . The sensor was capable of resolving spatial- and time-varying components of shear stress in the abdominal aorta. Computational fluid dynamic code based on non-Newtonian fluid properties showed comparable results within an acceptable range of experimental errors ( plusmn9%) for the maximal and minimal values in shear stress during one cardiac cycle. Therefore, we demonstrated the capability of biocompatible sensors for real-time shear stress measurement in vivo with a potential to advance the understanding between the blood flow and vascular disease. View full abstract»

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  • A Hybrid Electrode Array With Built-In Position Sensors for an Implantable MEMS-Based Cochlear Prosthesis

    Page(s): 1187 - 1194
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    A hybrid electrode array has been developed for use in an implantable MEMS-based cochlear prosthesis intended to restore hearing to the profoundly deaf. The array provides high-density stimulation and embedded position sensing to improve sound perception, minimize insertion damage, and optimize implant placement. Interfacing with a hermetically-packaged microcontroller and a bidirectional wireless interface over an eight-lead polymeric cable, the array integrates custom signal-processing electronics with thin-film lithographically defined IrO electrodes and polysilicon position sensors. The signal-processing chip (2.4 mm times 2.4 mm) operates from plusmn2.5 V, accepts 16-b commands, and performs command validation, stimulus current generation, site/sensor selection, offset compensation, and output-signal conditioning. The array contains nine polysilicon strain gauges to detect array position and tip contact. These strain sensors have gauge factors of 15-20, allowing the array tip position to be determined within 50 mum while providing tip-contact signals of more than 100 mV. The on-chip signal processing allows the use of a standard bus interface, reduces the parasitic capacitance and noise coupling on the connecting cables, allows the array shape to be imaged at a rate up to 10 times per second, and suppresses the output noise down to 3 mV. View full abstract»

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  • Development of a Latchable Microvalve Employing a Low-Melting-Temperature Metal Alloy

    Page(s): 1195 - 1203
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    We present the design, fabrication, and characterization of a latchable microvalve. The valve can be held in the on- or off-state without consuming power. A low-melting-temperature metal alloy provides structural support to hold the valve in place when latched. The metal alloy piece liquefies when it is heated above 62degC, allowing a pneumatic actuator to change the valve state. When the metal cools and solidifies, the valve is once again latched. This type of valve may be useful for portable lab-on-a-chip devices that require low-power operation and long-term fluid storage. A thin-film metal heater has been integrated into the polydimethylsiloxane device to provide localized heating for individual valve elements. Valve closing and opening response times have been simulated and verified by experiment. The burst pressure has been experimentally characterized and parameters influencing this burst pressure have been modeled. View full abstract»

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  • Simultaneous On-Chip Sensing and Actuation Using the Thermomechanical In-Plane Microactuator

    Page(s): 1204 - 1209
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    Many applications in microelectromechanical systems require physical actuation for implementation or operation. On-chip sensors would allow control of these actuators. This paper presents experimental evidence showing that a certain class of thermal actuators can be used simultaneously as an actuator and a sensor to control the actuator's force or displacement output. By measuring the current and voltage supplied to the actuator, a one-to-one correspondence is found between a given voltage and current and a measured displacement or force. This integrated sensor/actuator combination will lead to efficient on-chip control of motion for applications including microsurgery, biological cell handling, and optic positioning. View full abstract»

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  • Polydimethylsiloxane Microlens Arrays Fabricated Through Liquid-Phase Photopolymerization and Molding

    Page(s): 1210 - 1217
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    We report on polydimethylsiloxane (PDMS) microlens arrays fabricated through liquid-phase photopolymerization and molding. The gist of this fabrication process is to form liquid menisci of variable radii of curvature at an array of apertures through pneumatic control, followed by photopolymerization under ultraviolet radiance. The resultant polymerized structures are then transferred to PDMS utilizing two molding steps. By adjusting the pneumatic pressure during the process, a single aperture array can be used to fabricate PDMS microlens arrays with variant focal lengths. The liquid menisci are formed by liquid-air interfaces that are pinned at the top edges of the apertures along hydrophobic-hydrophilic boundaries generated through surface chemical treatments. The microlens arrays are optically characterized. Variant focal lengths from 2.35 to 5.54 mm and f-numbers from 1.27 to 5.88, dependent on the diameter of apertures and the applied pressure to form the liquid menisci, are achieved with this relatively simple process and match well with the physical model. Owing to the formation from the liquid-air interfaces, the surface roughness of microlenses is measured to be around 25 nm. View full abstract»

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  • Tunable Pneumatic Microoptics

    Page(s): 1218 - 1227
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    A new class of tunable and actuated microoptical devices is presented: pneumatic microoptics. Using microelectromechanical system fabrication technology extended by the use of polydimethylsiloxane (PDMS) membranes, tunable microlenses, and lens arrays, actuated micromirrors with large tilt angles and tip-tilt piston mirrors have been designed and fabricated. Actuation is by pressure: Gas- or liquid-filled microfluidic cavities are employed to distend the microfabricated PDMS structures which then act as a lens surface or as an actuator for a micromirror. Thermopneumatic actuation is also employed for completely integrated tunable optical systems in which all actuator and optical components are fabricated on-chip. The technology is particularly promising for microsystem applications in which significant movement is required but high voltages or external fields are impractical. [2007-0301]. View full abstract»

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  • Pull-In Analysis of Torsional Scanners Actuated by Electrostatic Vertical Combdrives

    Page(s): 1228 - 1238
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    This paper presents pull-in analysis of torsional MEMS scanners actuated by electrostatic vertical combdrives with general comb gap arrangements and cross sections. The analysis is based on a 2-DOF actuator with a single voltage control. Three failure modes of the scanners are identified as in-plane twist, transversal motion, and out-of-plane twist. For each failure mode, analytical expressions of pull-in deflection are obtained by applying 2D analytical capacitance models to the derived pull-in equations. From these, the dominant pull-in mechanism is shown to be in-plane twist for scanners with high-aspect-ratio torsional springs. The analytical calculations for both symmetric and asymmetric capacitances are shown to be in good agreement with simulation results. The optimum scanner design is achieved when the pull-in deflection matches the capacitance maximum angle. The condition can be expressed in terms of the ratio of the comb thickness to the comb gap, which is smaller than the typical aspect ratio of deep reactive ion etching. The optimum tradeoff between the maximum deflection angle and the number of movable combs is achieved by adjusting the overlap of the movable and fixed combs and the distance of the comb sets from the axis of the rotation. View full abstract»

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  • A Microcantilever-Based Picoliter Droplet Dispenser With Integrated Force Sensors and Electroassisted Deposition Means

    Page(s): 1239 - 1253
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    This paper introduces a picoliter droplet dispenser relying on an array of silicon microcantilevers. The microcantilevers bear fluidic channels, and liquid transfer is achieved by a direct contact of the cantilever tip and the surface. A high degree of control over the location and geometry of the fabricated patterns is ensured by incorporating force sensors and electroassisted deposition means, i.e., electrowetting actuation and electrospotting, to the devices. The cantilever array, a PC-controlled stage, and an electronic circuit dedicated to the piezoresistance measurements form a closed-loop system that enables the automatic displacement of the array and the control of the deposition parameters. By using an external loading chip, different liquids are loaded onto the cantilevers, enabling the parallel deposition of several entities in a single spotting run. This paper details the design of the cantilevers assisted by finite-element modeling, the fabrication of the cantilever array, and the closed-loop operation. Moreover, proof-of-concept experiments are presented to demonstrate the versatility of our deposition system in terms of deposited materials and spot sizes. The control of the spotting process, the versatility of the printed materials, and the added electroassisted features prove that this tool has a real potential for research work and industrial applications. View full abstract»

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  • Liquid Aspiration and Dispensing Based on an Expanding PDMS Composite

    Page(s): 1254 - 1262
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    In this paper, we present the development of active liquid aspiration and dispensing units designed for vertical, as well as lateral, liquid aspiration. The devices are based on a single-use thermally expanding polydimethylsiloxane (PDMS) composite, which allows altering its surface topography by means of individually addressable integrated heaters. Devices are designed in order to create an enclosed cavity in the system, due to locally expanding the initially unstructured composite. This enables negative volume displacement and leads to the event of liquid aspiration. To enable this device functionality, two different techniques of selectively creating permanent PDMS bonds have been developed. One approach utilizes the plasma-assisted PDMS bonding technique, together with a patterned antistiction layer to form reversibly, as well as irreversibly, bonded regions. Another approach utilizes microcontact printing of PDMS curing agent, which serves as a patterned intermediate layer for adhesive bonding. Fabricated prototype devices successfully demonstrated the aspiration and release of liquid volumes ranging from 28 to 815 nL. The devices are entirely fabricated from low-cost materials, using wafer-level processes only and do not require external means for liquid actuation. View full abstract»

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  • Silicon Field-Emission Devices Fabricated Using the Hydrogen Implantation–Porous Silicon (HI–PS) Micromachining Technique

    Page(s): 1263 - 1269
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    This paper presents a relatively simple method to fabricate field-emitter arrays from silicon substrates. These devices are obtained from silicon micromachining by means of the HI-PS technique - a combination of hydrogen ion implantation and porous silicon used as sacrificial layer. Also, a new process sequence is proposed and implemented to fabricate self-aligned integrated field-emission devices based on this technique. Electrical characteristics of the microtips obtained show good agreement with the Fowler-Nordheim theory, which are suitable for the proposed application. View full abstract»

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  • Fabrication and Testing of a High-Speed Microscale Turbocharger

    Page(s): 1270 - 1282
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    A microelectromechanical system (MEMS) turbocharger has been designed, fabricated, and tested as part of a Massachusetts Institute of Technology program aimed at producing a microfabricated gas turbine engine for portable power applications. A gas turbine engine requires high-speed high-efficiency turbomachinery operating at tip speeds of several hundred meters per second. This MEMS turbocharger serves to demonstrate these requirements. The turbocharger's silicon rotor, which is supported on hydrostatic gas thrust and journal bearings in a silicon stator housing, was spun to 480 000 rpm, corresponding to a tip speed of 200 m/s. This paper discusses critical fabrication processes that enabled the capabilities of this device. Operational issues and test results are also presented. The turbocharger's compressor demonstrated a pressure ratio of 1.21 at a mass flow rate of 0.13 g/s, with a combined compressor-turbine spool efficiency of 0.24. Under these conditions, the turbine produced about 5 W of power. Results from the simultaneous operation of a spinning rotor and burning combustor within the microscale turbocharger are also presented. Experimental results compare well with analytical models and computations. View full abstract»

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Aims & Scope

The topics of interest include, but are not limited to: devices ranging in size from microns to millimeters, IC-compatible fabrication techniques, other fabrication techniques, measurement of micro phenomena, theoretical results, new materials and designs, micro actuators, micro robots, micro batteries, bearings, wear, reliability, electrical interconnections, micro telemanipulation, and standards appropriate to MEMS. Application examples and application oriented devices in fluidics, optics, bio-medical engineering, etc., are also of central interest.

Full Aims & Scope

Meet Our Editors

Editor-in-Chief
Christofer Hierold
ETH Zürich, Micro and Nanosystems