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Microelectromechanical Systems, Journal of

Issue 3 • Date June 2005

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Displaying Results 1 - 25 of 30
  • Table of contents

    Page(s): c1 - c4
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  • Journal of Microelectromechanical Systems publication information

    Page(s): c2
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  • Design and optimization of a MEMS electret-based capacitive energy scavenger

    Page(s): 429 - 435
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    In this paper, a method for the design and optimization of an electret-based vibration-to-electric microconverter is presented, using a nonlinear dynamical model of the device. The dynamics of the converter is analyzed in detail, showing the importance of properly accounting for the nonlinearity in the optimization process. A procedure to determine a set of optimization parameters is finally presented. View full abstract»

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  • Optimization of a thermal flow sensor for acoustic particle velocity measurements

    Page(s): 436 - 443
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    In this paper, a thermal flow sensor consisting of two or three heated wires, the Microflown, is treated for application to acoustic measurements. It is sensitive to flow ("particle velocity"), contrary to conventional microphones that measure acoustic pressures. A numerical analysis, allowing for detailed parametric studies, is presented. The results are experimentally verified. Consequently, improved devices were fabricated, and also sensors with a new geometry consisting of three wires, instead of the usual two, of which the central wire is relatively most heated. These devices are the best performing Microflowns to date with a frequency range extending from 0 to over 5 kHz and a minimum detectable particle velocity level of about 70 nm/s at 2 to 5 kHz (i.e., 3 dB PVL or SPL, corresponding to a pressure of 3.1·10-5 Pa at a free field specific acoustic impedance). View full abstract»

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  • An x-axis single-crystalline silicon microgyroscope fabricated by the extended SBM process

    Page(s): 444 - 455
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    A high-aspect ratio, single-crystal line silicon x-axis microgyroscope is fabricated using the extended sacrificial bulk micromachining (SBM) process. The x-axis microgyroscope in this paper uses vertically offset combs to resonate the proof mass in the vertical plane, and lateral combs to sense the Coriolis force in the horizontal plane. This requires fabricating vertically and horizontally moving structures for actuation and sensing, respectively, which is very difficult to achieve in single-crystalline silicon. However, single-crystalline silicon high-aspect ratio structures are preferred for high performance. The extended SRN/I process is a two-mask process, but all structural parts and combs are defined in one mask level. Thus, there is no misalignment in any structural parts or comb fingers. In this extended SBM process, all vertical dimensions of the structure, including the comb height, vertical comb offset and sacrificial gap, can be defined arbitrarily (up to a few tens of micrometers). For electrical isolation, silicon-on-insulator (SOI) wafers are used, but the inherent footing phenomenon in the SOI deep etching is eliminated and smooth structural shapes are obtained, because the SBM process is used. In the fabricated x-axis microgyroscope, the lower combs used to vibrate the proof mass are vertically offset 12 μm from the upper combs. The fabricated x-axis microgyroscope can resolve 0.1 deg/s angular rate, and the measured bandwidth is 100 Hz. The reported work represents the first x-axis single-crystalline silicon microgyroscope fabricated using only one wafer without wafer bonding. We have previously reported several versions of z-axis microgyroscopes and x-, y-, and z-axis accelerometers, using the SBM process. The results or this paper allow integrating x-, y-, and z-axis microgyroscopes as well as x-, y-, and z-axis microaccelerometers in one wafer, using the same mask and the same process. View full abstract»

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  • Reconfigurable millimeter-wave filters using CPW-based periodic structures with novel multiple-contact MEMS switches

    Page(s): 456 - 463
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    In this paper, fully monolithic reconfigurable millimeter-wave filters are proposed using the CPW-based periodic structures with novel multiple-contact MEMS switches. Millimeter-wave low-pass and band-pass filters were designed, fabricated, and tested. Three cascaded CPW-based periodic structures, with low-pass and band-pass intrinsic filtering characteristics, are reconfigured into a self-similar single unit cell by the operation of the novel multiple-contact MEMS switches with single actuation. By using the multiple-contact MEMS switches, the insertion loss can be reduced and the operating frequency ranges are extended to millimeter-waves with little increase of loss. Additionally, the number of the switching elements has been reduced and the bias-decoupling circuits are not required, resulting in a very small chip size. The measured results of the reconfigurable low-pass filter show the 3-dB cutoff frequency change from 67 to 28 GHz with very small change in the insertion loss from 0.32 to 0.27 dB. The center frequency of the reconfigurable band-pass filter is tuned from 55 to 20 GHz, and the measured 3-dB cutoff bandwidth changed from 32 to 12 GHz, while the average insertion loss changed from 1.27 to 1.61 dB. The chip size of the low-pass and band-pass filter including dc bias line is 1.2 mm × 1.5 mm and 1.2 mm × 4.5 mm, respectively. View full abstract»

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  • RF MEMS membrane switches on GaAs substrates for X-band applications

    Page(s): 464 - 471
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    Micromechanical switches have demonstrated great potential at microwave frequencies. For low-loss applications at microwave frequencies, it is important to use high-resistivity substrates. This paper presents the design and fabrication of the shunt-capacitive MEMS switch on GaAs substrates. Analytical mechanical and impedance models of the membrane switch are given, and the results are confirmed by using the ANSYS and HFSS software, respectively. A surface micromachining process, which is compatible with the conventional millimeter-wave integrated circuits (MMICs) fabrication technology, was adopted to fabricate the RF switch on GaAs substrates. Its S-parameter was taken using a HP8510C vector network analyzer and a Cascade Probe station. The measured insertion loss of the switch and its associated transmission line is less than 0.25 dB from 1 to 25.6 GHz, and the isolation may reach -42 dB at its self-resonate frequency of 24.5 GHz. The actuation voltage is about 17 V. The switch has demonstrated lifetimes as long as 5×106 cycles. The wideband high performance in isolation and insertion loss offers the monolithic integration capability with GaAs MMICs. View full abstract»

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  • Arrays of hollow out-of-plane microneedles for drug delivery

    Page(s): 472 - 479
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    Drug delivery based on MEMS technology requires an invasive interface such as microneedles, which connects the microsystem with the biological environment. Two-dimensional arrays of rigid hollow microneedles have been fabricated from single-crystal silicon using a combination of deep reactive ion etching and isotropic etching techniques. The fabricated needles are typically 200 μm long with a wide base and a channel diameter of 40 μm. The fabrication process allows creating either blunt needles or needles with sharp tips. Their shape and size make these needles extremely suitable for minimally invasive painless epidermal drug delivery. MEMS technology allows for batch fabrication and integration with complex microsystems. Fluid has been successfully injected 100 μm deep into sample tissue through arrays of microneedles. Needle breakage did not occur during this procedure. Experiments have shown that the modified Bernoulli equation is a good model for liquid flowing through the narrow microneedle lumen. View full abstract»

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  • A three-dimensional dielectrophoretic particle focusing channel for microcytometry applications

    Page(s): 480 - 487
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    In this paper, we have designed and fabricated a microfluidic channel to focus biological cells using dielectrophoresis for cytometry applications. The device consists of an elliptic-like channel fabricated by isotropic etching of soda lime glass wafers and a subsequent wafer-bonding process. Microelectrodes are patterned on the circumference of the channel to generate ac fringing fields that result in negative dielectrophoretic forces directing cells from all directions to the center of the channel. An analysis using a thin shell model and experiments with microbeads and human leukemia HL60 cells indicate that biological cells can be focused using an ac voltage of an amplitude up to 15 Vp-p and a frequency below 100 kHz, respectively. This design eliminates the sheath flow and the fluid control system that makes conventional cytometers bulky, complicated, and difficult to operate, and offers the advantages of a portable module that could potentially be integrated with on-chip impedance or optical sensors into a micro total analysis system. View full abstract»

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  • A hybrid PZT-silicon microvalve

    Page(s): 488 - 497
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    A low-voltage, low-power microvalve for compact battery-powered portable microfluidic platforms is designed, fabricated and experimentally characterized. The microvalve employs laser-machined piezoelectric unimorphs mechanically linked to surface micromachined nickel structures anchored on corrugated SixNy-Parylene composite membrane tethers. The Parylene layer also serves as a compliant sealing layer on the valve seat for reducing the leakage in the off state. A mechanical linking process to connect the bulk piezoelectric unimorphs to micromachined diaphragms in a self-aligned manner has been developed. The design enables large strokes (2.45 μm) at low-actuation voltages (10 V) consuming a comparatively low switching energy (678 nJ). The dependence of the measured flow rates on the modulated clearance over the orifice was found to be in good agreement with the theory of laminar flow in the low (1-100) Reynolds number regime. The microvalve was experimentally characterized for both gas and liquid flows. For example, at 10 V unimorph actuation, a gas flow rate of 420 μL/min at a differential pressure of 9.66 kPa was measured. The off-state leakage rate for 0 V actuation is estimated to be 10-20 μL/min. Typical flow rates with pulse width modulated (PWM) actuation with 50% duty cycle at 20 Vpp (1 kHz) were measured to be 770 μL/min at 6.9 kPa for gases and 2.77 μL/min at 4.71 kPa for liquids. View full abstract»

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  • Multiple-stage microfabricated preconcentrator-focuser for micro gas chromatography system

    Page(s): 498 - 507
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    The design, fabrication, and characterization of a multiple-stage Si microfabricated preconcentrator-focuser (μPCF) for a micro gas chromatography (μGC) system that can provide real-time quantification and identification of complex organic vapor mixtures are presented. The μPCF consists of a Si microheater loaded with Carbopack B, Carbopack X, and Carboxen 1000 carbon adsorbent granules, and a Si micromachined cover plate. Deep reactive ion etching is utilized to produce mechanically robust fluidic interconnection adapters hermetically sealed to fused silica capillary tubing for connection to the other components in the μGC. This three-stage device is designed to capture compounds spanning up to 4 orders of magnitude in volatility. The dead volume, thermal mass, heating efficiency, and pressure drop of the three-stage μPCF are improved significantly over its single-stage μPCF predecessor. We demonstrate the successful capture, desorption, and high-resolution chromatographic separation of a mixture of 30 common organic vapors using our three-stage μPCF in a conventional GC system. The peak width at half height is <2.05 s for all compounds after elution from the GC column. View full abstract»

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  • Design, fabrication, and characterization of a submicroelectromechanical resonator with monolithically integrated CMOS readout circuit

    Page(s): 508 - 519
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    In this paper, we report on the main aspects of the design, fabrication, and performance of a microelectromechanical system constituted by a mechanical submicrometer scale resonator (cantilever) and the readout circuitry used for monitoring its oscillation through the detection of the capacitive current. The CMOS circuitry is monolithically integrated with the mechanical resonator by a technology that allows the combination of standard CMOS processes and novel nanofabrication methods. The integrated system constitutes an example of a submicroelectromechanical system to be used as a cantilever-based mass sensor with both a high sensitivity and a high spatial resolution (on the order of 10-18 g and 300 nm, respectively). Experimental results on the electrical characterization of the resonance curve of the cantilever through the integrated CMOS readout circuit are shown. View full abstract»

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  • An approach for increasing drive-mode bandwidth of MEMS vibratory gyroscopes

    Page(s): 520 - 528
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    The limitations of the photolithography-based micromachining technologies defines the upper-bound on the performance and robustness of micromachined gyroscopes. Conventional gyroscope designs based on matching (or near-matching) the drive and sense modes are extremely sensitive to variations in oscillatory system parameters that shift the natural frequencies and introduce quadrature errors. Nonconventional design concepts have been reported that increase bandwidth to improve robustness, but with the expense of response gain reduction. This paper presents a new approach that may yield robust vibratory MEMS gyroscopes with better gain characteristics while retaining the wide bandwidth. The approach is based on utilizing multiple drive-mode oscillators with incrementally spaced resonance frequencies to achieve wide-bandwidth response in the drive-mode, leading to improved robustness to structural and thermal parameter fluctuations. Enhanced mode-decoupling is achieved by distributing the linear drive-mode oscillators radially and symmetrically, to form a multidirectional linear drive-mode and a torsional sense-mode; minimizing quadrature error and zero-rate output. The approach has been implemented on bulk-micromachined prototypes fabricated in a silicon-on-insulator (SOI)-based process, and experimentally demonstrated. View full abstract»

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  • Mechanical stability of a latching MEMS variable optical attenuator

    Page(s): 529 - 538
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    The mechanical stability of a latching shutter-insertion variable optical attenuator formed by deep reactive ion etching of bonded silicon-on-insulator (BSOI) is considered. The device can be continuously adjusted or latched into a discrete set of attenuation states using a rack-and-tooth mechanism. Simple numerical and analytic theories are developed to describe the effect of latching. The dynamics of the mechanism are characterized using internal actuation and it is shown that the use of a levered mechanism gives rise to several underdamped, low-frequency in-plane resonances during analog adjustment. Elastic nonlinearity is also identified. Vibration testing is then performed using an external piezoelectric transducer. It is shown that the effect of engaging the latch is to upshift the frequency of the most important mechanical resonance, reducing sensitivity to vibration in fixed attenuation states. View full abstract»

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  • Design, modeling, fabrication, and performances of bridge-type high-performance electroactive polymer micromachined actuators

    Page(s): 539 - 547
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    Bridge-type high- performance polymer micromachined actuators (PMATs) based on an electroactive polymer, modified poly(vinylidene fluoride-trifluoroethylene) [P(VDF-TrFE)] copolymer had been designed, modeled, fabricated, and characterized. The results show that the material enables the PMAT to exhibit a high stroke level (60 μm displacement with 1 mm lateral dimension microactuator) with high-load capability and high-displacement voltage ratio (DVR) over a broad frequency range (>100 kHz). The stroke reduction in fluid (Silicone oil) is less than 5% comparing with the displacement in air. Impedance analysis and displacement measurement indicate that the PMAT has strong resonance behavior and the resonance frequency can be tuned by varying the dc bias field. Furthermore, the resonance peak, as expected by theoretical study, shifted to 6.5 times lower in fluid than in air with the mechanical Q value reduction less than 40%. In addition, the performance of the PMAT was modeled based on the elastic and electromechanical properties of the materials utilized in the PMAT and the configuration of the device. The comparison between the model and the experimental result shows a good agreement and validates the model as an effective method for the future development of PMAT for various applications. The high frequency response and respected performance in fluid medium demonstrate that the PMAT has potential for high performance MEMS components in the applications of microfluid systems, air dynamic control, under water transducers, and mass sensors, etc. View full abstract»

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  • A single-layer PDMS-on-silicon hybrid microactuator with multi-axis out-of-plane motion capabilities-Part i: design and analysis

    Page(s): 548 - 557
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    This paper proposes a new single-layer electrostatic microactuator design that generates three-axis motion resulting in vertical translation and out-of-plane tilting. The new actuator design combines a micrometer-scale three-dimensional (3-D) polydimethylsiloxime (PDMS) structure fabricated using soft lithography with comb drives processed using a single mask on a silicon-on-insulator (SOI) wafer. The multi-axis actuation capability of the proposed actuator is enabled by coupling the in-plane actuation motion of the comb drives with the elastic bending of PDMS flexural microjoints. To predict the static and dynamic performance of the actuator, this paper develops a four-bar-linkage model and applies Lagrangian dynamics theory. The developed analytical model is validated using finite element analysis (FEA) and allows us to perform parametric design of the actuator. The analysis indicates that the proposed PDMS-on-silicon hybrid actuator can yield the desired multi-axis actuation capability with a dynamic bandwidth as large as 5 kHz. View full abstract»

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  • A single-layer PDMS-on-silicon hybrid microactuator with multi-axis out-of-plane motion capabilities-part II: fabrication and characterization

    Page(s): 558 - 566
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    This paper reports on fabrication and characterization of a new electrostatic microactuator that achieves out-of-plane multi-axis motion with a single silicon device layer. The multi-axis motion with the simple actuator design is possible by incorporating a three-dimensional (3-D) polydimethylsiloxane (PDMS) microstructure. This paper develops a new device processing method named "Soft-Lithographic Lift-Off and Grafting (SLLOG)" to fabricate the previously designed PDMS-on-silicon hybrid actuator structure. SLLOG is a low-temperature (less than 150°C) process that allows replica molded PDMS microstructures to be integrated in silicon micromachined device patterns. The fabricated actuator is characterized using laser vibrometry. The experimental results demonstrate actuation motions achieved in three independent axes with fast dynamic response reaching a bandwidth of about 5 kHz. The fabricated PDMS-on-silicon actuator yields a vertical displacement up to 5 μm and rotational motions with a 0.6-° tilting angle at a 40-V peak-to-peak ac actuation voltage. View full abstract»

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  • Polycrystalline silicon-carbide surface-micromachined vertical resonators-part I: growth study and device fabrication

    Page(s): 567 - 578
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    This manuscript is the first of a two-part series describing the fabrication and testing of MHz frequency, polycrystalline silicon-carbide (poly-SiC) micromechanical resonators made from films deposited by atmospheric-pressure chemical-vapor deposition (APCVD). In Part I, the development of deposition and patterning techniques suitable for the fabrication of vertically actuated, clamped-clamped beam resonant structures is detailed. Recipe development involved film deposition and material analysis on both planar and patterned substrates. We found that a carbonization-based deposition process modeled after epitaxial growth of 3C-SiC on Si produced the highest quality poly-SiC films for use with sub-micron thick polysilicon sacrificial layers, regardless of topology. Devices utilizing beam thicknesses up to 1 μm were fabricated and successfully released. Details about the testing of the released structures are presented in Part 2 of this series (see Wiser, Tabib-Azar, Mehregan, and Zorman, "Polycrystalline silicon-carbide surface-micromachined vertical resonators-Part II: Electrical testing and material property extraction", J. Microelectromech. Syst., vol. 14, no. 3, Jun. 2005). View full abstract»

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  • Polycrystalline silicon-carbide surface-micromachined vertical resonators-part II: electrical testing and material property extraction

    Page(s): 579 - 589
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1856 KB) |  | HTML iconHTML  

    This manuscript is the second of a two part series describing the fabrication and testing of megahertz frequency, polycrystalline silicon-carbide (poly-SiC) micromechanical resonators made from films deposited by atmospheric pressure chemical vapor deposition. In Part I, the development of deposition and patterning techniques suitable for the fabrication of vertically actuated, clamped-clamped beam resonant structures was detailed (see Wiser, Chung, Mehregan, and Zorman, "Polycrystalline Silicon-Carbide Surface-Micromachined Vertical Resonators-Part I: Growth Study and Device Fabrication," J. Microelectromech. Syst., vol. 14, no. 3, Jun. 2005). This paper describes the testing procedures used to determine the nominal resonant frequencies and quality factors for these resonators, as well as the methods used to calculate the Young's modulus and residual stress of the poly-SiC films from the resonant frequency data. Poly-SiC devices with a resonant frequency ranging from 1 to 4 MHz and quality factors of around 2500 were successfully tested. The quality factors were lower than expected for devices of this design. Modeling and experimental results indicate that the low values are likely due to insufficient doping in the poly-SiC films. Both the Young's modulus and residual stress values calculated for the poly-SiC films (436 GPa and 121 MPa, respectively) compare favorably with values reported in the literature. View full abstract»

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  • Studies on surface wettability of poly(dimethyl) siloxane (PDMS) and glass under oxygen-plasma treatment and correlation with bond strength

    Page(s): 590 - 597
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    An issue in microfabrication of the fluidic channels in glass/poly (dimethyl siloxane) (PDMS) is the absence of a well-defined study of the bonding strength between the surfaces making up these channels. Although most of the research papers mention the use of oxygen plasma for developing chemical (siloxane) bonds between the participating surfaces, yet they only define a certain set of parameters, tailored to a specific setup. An important requirement of all the microfluidics/biosensors industry is the development of a general regime, which defines a systematic method of gauging the bond strength between the participating surfaces in advance by correlation to a common parameter. This enhances the reliability of the devices and also gives a structured approach to its future large-scale manufacturing. In this paper, we explore the possibility of the existence of a common scale, which can be used to gauge bond strength between various surfaces. We find that the changes in wettability of surfaces owing to various levels of plasma exposure can be a useful parameter to gauge the bond strength. We obtained a good correlation between contact angle of deionized water (a direct measure of wettability) on the PDMS and glass surfaces based on various dosages or oxygen plasma treatment. The exposure was done first in an inductively coupled high-density (ICP) plasma system and then in plasma enhanced chemical vapor deposition (PECVD) system. This was followed by the measurement of bond strength by use or the standardized blister test. View full abstract»

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  • Wet-etch release process for silicon-micromachined structures using polystyrene microspheres for improved yield

    Page(s): 598 - 602
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    One of the final steps in fabricating microelectromechanical devices often involves a liquid-etch release process. Capillary forces during the liquid evaporation stage after the wet-etch process can pull two surfaces together resulting in adhesion of suspended microstructures to the supporting substrate. This release-related adhesion can greatly reduce yields. In this paper, we present a wet-etch release method that uses polystyrene microspheres in the final rinse liquid. The polystyrene microspheres act as physical barriers between the substrate and suspended microstructures during the final liquid evaporation phase. A plasma-ashing process is utilized to completely remove the polystyrene microspheres from the microstructure surfaces. Using this process, release yields >90% were achieved, as compared to yields of 20-50% when the polystyrene microspheres were not included. This release process is inexpensive, easy to implement, and is effective for both single-crystal and polycrystalline silicon MEMS devices. View full abstract»

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  • Fine ZnO patterning with controlled sidewall-etch front slope

    Page(s): 603 - 609
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    This paper describes a wet-etching technique that solves the major difficulty of fine patterning a c-axis oriented polycrystalline ZnO film. The technique uses aqueous NH4Cl with electrolytically added copper ions and convection flow, and for the first time, allows the ZnO film to be etched 1) with controlled etch rate ratio between the vertical and horizontal etch rates and 2) with controlled etch-front slope. The ratio between the vertical and horizontal etch rates is as high as 20 to 1, while the angle between the sidewall etch-front surface and the substrate surface can be electrically controlled between 73° and 106°. Also, ZnO films can now be patterned to fine features (even sub-μm level) with a wet etchant. The electroless galvanic etching technique described in this paper produces uniform etching over a large area (larger than 3" in diameter). View full abstract»

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  • Micromachined III-V multimorph actuators for MOEMS applications - concept, design, and model

    Page(s): 610 - 618
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    A multimorph configuration of III-V materials that is based on the global optimization method using the simulated annealing (SA) algorithm is proposed to enhance small intrinsic piezoelectric effect of such materials. In this paper, a novel piezoelectric multimorph microactuator design such as a five-layer multimorph is proposed and analyzed using both numerical and analytical methods for potential microoptoelectromechanical systems (MOEMS) applications. Previously published analytical multimorph models for MEMS, which have been shown to reduce to equivalent expressions, are also presented and used for design optimization. By imposing a set of "real-world" constraints on the designs, optimal device geometries, which are more realistic and visible, have been determined using the SA method. Design tradeoffs are also discussed in terms of potential utility for the multimorph actuator in MOEMS applications. Finally, the proposed multimorph models are verified by finite element simulations results. View full abstract»

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  • Precision poly-(dimethyl siloxane) masking technology for high-resolution powder blasting

    Page(s): 619 - 624
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    Powder blasting micro-erosion is a fast and flexible technique for the micropatterning of brittle materials. We have combined 10 μm diameter Al2O3 eroding particles with a new masking technique to realize the smallest possible structures with the powder blasting process (30 μm). Our masking technology is based on the sequential combination of two polymers: 1) the brittle epoxy resin SU8 for its photosensitivity and 2) the elastic and thermo-curable poly-(dimethyl siloxane) (PDMS) for its large erosion resistance. We have micropatterned glass microstructures with aspect ratio 1 and structural details down to 20 μm. We compare the mask size-dependent etching rate using both 1.0 and 30 jam diameter Al2O3 particles and find a decreasing etching rate for structures that are smaller than about 10 times the particle size. Combining SU8 with PDMS proves to be a very easy and accurate masking technology that allows exploring the fundamental dimensional limits of the powder blasting micro-erosion process. View full abstract»

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  • A parametrized three-dimensional model for MEMS thermal shear-stress sensors

    Page(s): 625 - 633
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    This paper presents an accurate and efficient model of MEMS thermal shear-stress sensors featuring a thin-film hotwire on a vacuum-isolated dielectric diaphragm. We consider three-dimensional (3-D) heat transfer in sensors operating in constant-temperature mode, and describe sensor response with a functional relationship between dimensionless forms of hotwire power and shear stress. This relationship is parametrized by the diaphragm aspect ratio and two additional dimensionless parameters that represent heat conduction in the hotwire and diaphragm. Closed-form correlations are obtained to represent this relationship, yielding a MEMS sensor model that is highly efficient while retaining the accuracy of three-dimensional heat transfer analysis. The model is compared with experimental data, and the agreement in the total and net hotwire power, the latter being a small second-order quantity induced by the applied shear stress, is respectively within 0.5% and 11% when uncertainties in sensor geometry and material properties are taken into account. The model is then used to elucidate thermal boundary layer characteristics for MEMS sensors, and in particular, quantitatively show that the relatively thick thermal boundary layer renders classical shear-stress sensor theory invalid for MEMS sensors operating in air. The model is also used to systematically study the effects of geometry and material properties on MEMS sensor behavior, yielding insights useful as practical design guidelines. 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