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Microelectromechanical Systems, Journal of

Issue 1 • Date Feb. 2013

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Displaying Results 1 - 25 of 35
  • 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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    Freely Available from IEEE
  • Near-Field Electrospray Microprinting of Polymer-Derived Ceramics

    Page(s): 1 - 3
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (404 KB) |  | HTML iconHTML  

    Ceramic microelectromechanical systems (MEMS) sensors are potentially game-changing devices in many applications in high-temperature and corrosive environments, where the use of conventional MEMS materials such as silicon is prohibited. However, the microfabrication of ceramic MEMS devices remains a major technical challenge. Here, we report a method to directly print micro ceramic patterns using near-field electrospray (ES) of polymer-derived ceramics (PDCs). We demonstrated that the viscous ceramic precursor liquids can be printed reliably without any clogging problem. The spray self-expansion due to Coulombic repulsion force among charged droplets can be suppressed by decreasing the droplet residence time in space. A spray expansion model is used to predict the line width, and the results are in decent agreement with the experiments. We demonstrated a 1-D printed polymer feature as narrow as 35 μm and a micro pentagram pattern. Moreover, after the pyrolysis of PDC at 1100 °C in nitrogen, amorphous alloys of silicon, carbon, and nitrogen (SiCN) are obtained. The samples show good integrity and adhesion to the substrate. The near-field ES PDC printing can become a useful addition to the toolbox of high-temperature MEMS. View full abstract»

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  • Fabrication and Characterization of Biologically Inspired Curved-Surface Artificial Compound Eyes

    Page(s): 4 - 6
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    Curved artificial compound eyes (CACEs) are fabricated using microscale replication, stamping, and casting processes to form deposited 2-D microlens-pattern composite films into 3-D structures. The films are made up of polydimethylsiloxane (PDMS)-Parylene-C-PDMS layers. The layers are used for pattern replication, isolation, and buffering, respectively. The effect of the buffer layer on the ultimate 3-D structure is discussed. Multiple images of the human face in lateral- and axial-motion modes are obtained by these CACE prototypes. These images are used to evaluate the capability of the CACE to acquire multiangle images. The results give evidence that CACEs can potentially produce stereovision in microoptical systems. View full abstract»

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  • A MEMS Bistable Device With Push-On–Push-Off Capability

    Page(s): 7 - 9
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (577 KB) |  | HTML iconHTML  

    This letter presents a novel MEMS bistable device that requires only one independent driving source for switching between its two stable states. The proposed device employs a mechanically push-on-push-off mechanism consisting of two curved beam structures. An integrated V-beam actuator (VBA) is used as the only actuation component. The proposed device can be easily realized on a silicon-on-insulator wafer by using the inductively coupled plasma (ICP) etching process with a single photomask. Preliminary measurement results show that a 30-ms pulse of 7.2 V applied to the VBA can drive the device from the off state to the on state, and a 50-ms pulse of 7.2 V can release the device from the on state back to the off state. Transient displacement results measured by using a vibrometer are also provided. View full abstract»

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  • Lateral Contact Three-State RF MEMS Switch for Ground Wireless Communication by Actuating Rhombic Structures

    Page(s): 10 - 12
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    A laterally actuated three-state RF microelectromechanical systems switch for ground wireless communication applications is proposed, fabricated, and tested. By electrostatically actuating a rhombic beam, the proposed switch can not only realize the off-state to on -state shifting but also provide an additional deep off state. The switch was fabricated by silicon on glass (SOG) bulk silicon micromachining. The 2- μm-thick gold electroplating layers were introduced in the SOG process to enhance the performance of lateral contacts. The off-state and deep- off-state isolations of the prototype switch were measured to be -67.6 dB and - 72.2 dB at 0.9 GHz and -48.3 dB and -53.0 dB at 6 GHz, respectively. The measured insertion loss is -0.13 dB at 0.9 GHz and -0.38 dB at 6 GHz, respectively. The measured actuation voltage is 78 V. The switching-on and switching-off response times are 72 and 64 μs, respectively. View full abstract»

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  • Optimization of Angular Alignment in Self-Assembly of Thin Parts at an Air–Water Interface

    Page(s): 13 - 15
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (498 KB) |  | HTML iconHTML  

    This letter presents an analysis of self-assembly of thin disk-shaped parts (diameter: 2 mm; thickness: 100 μm) with the objective of optimizing their angular alignment. The assembly proceeds continuously on a substrate that is pulled up through an air-water interface where thin parts with magnetic markers are floating. Angular deviations from the assembly site are significantly reduced by repositioning magnets that guide the self-assembly process. Temporary Faraday waves aid one-to-one part-to-site registration. Ninety parts are assembled, row by row, in 1 min. The assembly rate scales with the width of the assembly substrate. Compared with that of our previous work, the assembly rate is increased threefold due to reduced part-to-part interactions. View full abstract»

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  • Fatigue Degradation Properties of LIGA Ni Films Using Kilohertz Microresonators

    Page(s): 16 - 25
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    A micrometer-scale ultrasonic fatigue characterization technique is introduced to investigate the fatigue degradation properties of LIGA Ni structural films in the very high cycle fatigue regime. Kilohertz microresonators fabricated with the MetalMUMPs process were driven at resonance (~ 8 kHz) in controlled environments (30 °C , 50% relative humidity (RH); 80 °C, 5% RH; and 80 °C, 90% RH) to perform fatigue tests on 20-μm -thick Ni notched beams subjected to fully reversed bending over a wide range of stress amplitudes. It is shown that the fatigue degradation occurring at the notch, observed with scanning electron microscopy, can be quantified with the measured evolution of the microresonators' resonant frequency. The fatigue damage consists of extrusion formation and microcrack nucleation and does not propagate to form fatal cracks due to the extreme stress gradients at the notch. The resonant frequency evolution for fatigue tests performed at 80 °C, 90% RH suggests that stress-assisted oxidation in the presence of humid environments may accentuate fatigue damage formation. This experimental technique brings critical information regarding the long-term fatigue degradation properties of metallic microelectromechanical systems (MEMS) devices. In particular, this technique can allow controlled studies of the effects of fatigue localization and large stress gradients typically encountered in MEMS components. View full abstract»

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  • Comparison of MEMS PZT Cantilevers Based on d_{31} and d_{33} Modes for Vibration Energy Harvesting

    Page(s): 26 - 33
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    d 31 and d33 mode microelectromechanical systems piezoelectric energy harvesters (PEHs) were fabricated and compared to investigate their output powers converted from vibration. Both types of devices have the same dimensions in a cantilever structure and aim to effectively couple vibration from ambient conditions. The resonant frequencies of the cantilevers are 243 Hz. Two types of devices were compared using mathematical equations based on an equivalent circuit model. The output power of the d31 mode PEH was 2.15 μW and 2.33 μW in experiment and modeling, respectively. The d33 mode PEHs generated output power ranging between 0.62 and 1.71 μW when the width of the interdigital electrode (IDE) is ranging from 8 to 16 μm and finger spacing is varied from 4 to 16 μm. The output power of the d33 mode device strongly depends on the dimensions of IDE. The analysis of material constant and electrode design was conducted in conjunction with developing a mathematical equation. The result predicts that the output power of d33 mode PEH can be higher than that of d31 mode PEH when the finger width is reduced to 2 μm and finger spacing is between 8 and 20 μm. View full abstract»

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  • Interfacial Mechanical Properties of n -Alkylsilane Monolayers on Silicon Substrates

    Page(s): 34 - 43
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    The interfacial properties of n-alkylsilane monolayers on silicon were investigated by normal force spectroscopy, lateral force measurements, and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy. Monolayers of (CH3( CH2)n - 1SiCl3) with chain lengths n = 5, 8, 12, and 18 were prepared and NEXAFS spectra were used to compute the dichroic ratio, RI. As n decreased from 18 to 5, the film structures change from ordered (RI = 0.41) to disordered (RI = 0.12) states. Normal force spectroscopy data were analyzed with a modified elastic adhesive contact model to extract Young's modulus, Efilm, and the work of adhesion, w, of the film; Efilm decreased from 1.2 to 0.67 GPa, and w increased from 48.6 to 60.1 mJ·m-2 as n decreased from 18 to 5. Lateral force measurements quantified the reduction in friction via an interfacial shear strength, τ , and a lateral deformation analog, η. Monolayer adsorption reduced τ from 3500 MPa for SiO2 to less than 50 MPa for n = 12 and 18 alkylsilanes and was dependent on contact pressure. Conversely, η was pressure invariant, with values of ≈3500 MPa for n = 5 and 8 and ≈1000 MPa for n = 12 and 18. View full abstract»

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  • Investigation of Cellular Contraction Forces in the Frequency Domain Using a PDMS Micropillar-Based Force Transducer

    Page(s): 44 - 53
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    Polydimethylsiloxane (PDMS) micropillar-based biotransducers are extensively used in cellular force measurements. The accuracy of these devices relies on the appropriate material characterization of PDMS and modeling to convert the micropillar deformations into the corresponding forces. Cellular contraction is often accompanied by oscillatory motion, the frequency of which ranges in several hertz. In this paper, we developed a methodology to calculate the cellular contraction forces in the frequency domain with improved accuracy. The contraction data were first expressed as a Fourier series. Subsequently, we measured the complex modulus of PDMS using a dynamic nanoindentation technique. An improved method for the measurement of complex modulus was developed with the use of a flat punch indenter. The instrument dynamics was characterized, and the full contact region was identified. By incorporating both the Fourier series of contraction data and the complex modulus function, the cellular contraction force was calculated by finite-element analysis (FEA). The difference between the Euler beam formula and the viscoelastic FEA was discussed. The methodology presented in this work is anticipated to benefit the material characterization of other soft polymers and complex biological behavior in the frequency domain. View full abstract»

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  • Fabrication of a Microscale Device for Detection of Nitroaromatic Compounds

    Page(s): 54 - 61
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    Polymer layers displaying a specific swelling response in the presence of nitroaromatic compounds are integrated into microscale sensors. Blanket layers of the polymer are grown using initiated chemical vapor deposition, and lithographic techniques are used to define microscale polymer lines. A nanoscale metal line is perpendicularly overlaid across each polymer line. Exposure to nitroaromatic analytes causes the polymeric device component to expand, resulting in plastic deformation of the metal and a permanent change in the resistance measured across the device. The response is rapid and selective for nitroaromatic compounds; additionally, the small area, simplicity, and interchangeability of the device design facilitate the fabrication of sensors selective for other analytes and device arrays. Calculated limits of detection for 2,4,6-trinitrotoluene are 3.7 ppb at 20°C or 0.8 pg in a proof-of-concept device; methods for optimization are explored. View full abstract»

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  • Self-Patterned Gold-Electroplated Multicapillary Gas Separation Columns With MPG Stationary Phases

    Page(s): 62 - 70
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    Gas chromatography (GC) is a powerful analytical method to accurately and reliably identify the constituents of a complex mixture. There are numerous efforts to miniaturize GC system, in general, and separation columns, in particular, for rapid, dependable, and portable on-site analysis. This paper reports the development of two diverse self-patterned gold electrodeposition fabrication techniques for high-aspect-ratio microfluidic channels including multicapillary GC columns. First approach involves geometry-dependent tuned electroplating conditions to self-pattern gold along the vertical sidewalls without any deposition on horizontal top and bottom surfaces, while the second method provides highly conformal gold deposition inside the 3-D microchannels. Both reported approaches do not require a postdeposition patterning step while affording at the same time excellent bonding and stationary phase coating yields. The ability of thiol to self-assemble on gold surface is also utilized to form monolayer-protected gold (MPG) surfaces and is used as a stationary phase for micro GC. To evaluate the chromatographic performance of both schemes, 250-μm -deep 30-μm-wide 25-cm-long microfabricated multicapillary columns (μMCCs) with 16 channels are functionalized by self-assembly of octadecanethiol (C18H37 SH) to form the MPG surface. With about 7300-plate/m theoretical plates, these columns demonstrate the highest reported separation efficiency on 16-channel μMCCs and are capable of separating complex gas mixtures containing compounds with wide range of boiling points. View full abstract»

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  • Magnetoelectric Flexural Gate Transistor With Nanotesla Sensitivity

    Page(s): 71 - 79
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    Magnetic sensors capable of detecting tiny ac magnetic fields ranging from microtesla to picotesla are of great interest. In this paper, we demonstrate an integrated magnetoelectric (ME) flexural gate transistor with nanotesla magnetic field detection sensitivity at room temperature. The device capacitively couples a Metglas (Fe0.85B0.05Si0.1)-based magnetostrictive unimorph micromechanical cantilever beam to the gate of an n-channel field-effect transistor. Using this sensor configuration, a sensitivity of 0.23 mV/μT and a minimum detectable field of 60 nT/√Hz at 1 Hz and 1.5 mV/μT and 150 pT/√Hz at the flexural resonance of the cantilever structure of 4.9 kHz were obtained. The results demonstrate a significant improvement in the thin-film ME sensor integration with standard CMOS process and open the possibility of monolithic magnetic sensor arrays fabrication for biomedical imaging applications. View full abstract»

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  • A Microdischarge-Based Deflecting-Cathode Pressure Sensor in a Ceramic Package

    Page(s): 80 - 86
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    This paper describes a microdischarge-based pressure sensor for harsh liquid environments that utilizes a ceramic package sealed with a deflecting diaphragm that also serves as a cathode. Located within the package is a reference cathode and an anode. The microdischarges are created between the two cathodes and the anode. The external pressure deflects the diaphragm, varying the interelectrode spacing and changing the differential current between the two competing cathodes. The electrodes are fabricated from a Ni foil and separated by dielectric spacers within a micromachined glass cavity. The structures are enclosed within a 1.6-mm3 ceramic surface mount package. Device sensitivity is approximately 4900 ppm/ lbf/in2 (72 000 ppm/atm), and diaphragm displacement is approximately 0.15 μm/atm. View full abstract»

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  • Simple Removal Technology of Chemically Stable Polymer in MEMS Using Ozone Solution

    Page(s): 87 - 93
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    This paper reports simple removal technology for chemically stable polymers, such as SU-8, benzocyclobutene, polyimide, and carbonized resist, using ozone solution. Conventionally, these polymers are difficult to completely remove by O2 plasma and organic solutions because of inorganic additives and chemical stabilities. In this paper, the removability of ozone solution to these polymers was investigated. Etching experiments using aqueous and acetic acid solutions of ozone were performed, and the surfaces of etched samples were analyzed by scanning electron microscopy and X-ray photoelectron spectroscopy. It was demonstrated that the polymers could be etched and completely removed using the acetic acid and/or aqueous solutions of ozone. This strong polymer removability of the ozone solutions is attributed to the strong organic decomposition ability of ozone and the rinse effect to inorganic materials in wet process. View full abstract»

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  • SU-8 2002 Surface Micromachined Deformable Membrane Mirrors

    Page(s): 94 - 106
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1018 KB) |  | HTML iconHTML  

    This paper describes two surface micromachining processes, i.e., one using a wet-etch release and the other using a dry-etch release, to create deformable membrane mirrors made from a thin film of low-stress SU-8 2002. The mirrors are designed for electronic focus and aberration control in imaging systems, and exhibit a large range of motion and high optical quality. The processes result in free-standing membrane mirrors with in-plane film stress as low as 12.5 MPa while attaining well-defined lithographic features as small as 3 μm in a 2.5-μm-thick film. We achieved a maximum deflection of 14.8 μm for a 3-mm × 4.24-mm elliptical boundary mirror, limited by electrostatic pull-in. Using a 3-mm × 4.24-mm mirror, which is designed for operation with a circular beam at 45° incidence angle, we demonstrate focus control while compensating spherical aberration in an optical microscope over a depth of 137 μm using a 50× 0.4-NA objective lens. View full abstract»

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  • Resonance-Enhanced Piezoelectric Microphone Array for Broadband or Prefiltered Acoustic Sensing

    Page(s): 107 - 114
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (837 KB) |  | HTML iconHTML  

    We report an array of piezoelectric monocrystalline silicon microphones for audio-range acoustic sensing. Thirteen cantilever-type diaphragm transducers make up the array, each having a closely spaced and precisely controlled resonant frequency. These overlapping resonances serve to greatly boost the sensitivity of the array when the signals are added; if the signals are individually taken, the array acts as a physical filter bank with a quality factor over 40. Such filtering would enhance the performance and the efficiency of speech-recognition systems. In the “summing mode,” the array demonstrates high response over a large bandwidth, with unamplified sensitivity greater than 2.5 mV/Pa from 240 to 6.5 kHz. Both modes of operation rely on the precise control of resonant frequencies, often a challenge with large compliant microelectromechanical-system (MEMS) structures, where residual stress causes deformation. We mitigate these ill effects through the use of stress-compensating layer thicknesses and a stress-free monocrystalline diaphragm. For determining device geometry, we develop a simple analytical method that yields excellent agreement between designed and measured resonant frequency; all devices are within 4.5%, and four are within 0.5% (just several hertz). The technique could be useful not only for microphones but also for other low-frequency MEMS transducers designed for resonance operation at a specific frequency. View full abstract»

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  • MEMS Kinematics by Super-Resolution Fluorescence Microscopy

    Page(s): 115 - 123
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    Super-resolution fluorescence microscopy is used for the first time to study the nanoscale kinematics of a MEMS device in motion across a surface. A device under test is labeled with fluorescent nanoparticles that form a microscale constellation of near-ideal point sources of light. The constellation is imaged by widefield epifluorescence microscopy, and the image of each nanoparticle is fit to a Gaussian distribution to calculate its position. Translations and rotations of the device are measured by computing the rigid transform that best maps the constellation from one image to the next. This technique is used to measure the stepwise motion of a scratch drive actuator across each of 500 duty cycles with 0.13-nm localization precision, 1.85-nm displacement uncertainty, and 100-μrad orientation uncertainty for a constellation diameter of 15 μm. This novel measurement reveals acute aperiodic variations in the step size of the actuator, which have been neither previously observed nor predicted by any of the published models of the operation of the device. These unexpected results highlight the importance of super-resolution fluorescence microscopy to the measurement of MEMS kinematics, which will have broad impact in fundamental investigations of surface forces, wear, and tribology in MEMS and related applications. View full abstract»

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  • Two New Methods to Improve the Lithography Precision for SU-8 Photoresist on Glass Substrate

    Page(s): 124 - 130
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    This paper introduces two novel approaches to effectively eliminate the influence of scattering light from the wafer chuck and enhance the lithography precision of SU-8 photoresist on glass substrate. The first method is based on the fact that Si wafer can partially reflect ultraviolet (UV) light, and the second one employs materials that have low optical transparency and can achieve complete absorption of the near-UV light penetrating through the SU-8 photoresist and the glass substrate. The SU-8 structures produced by these two methods have much better profiles than those fabricated by the conventional process, and the linewidth deviation is smaller than 1 μm. The two routines have advantages of simplicity and low cost, therefore are applicable to batch fabrication, and can significantly enhance the performance of microelectromechanical systems devices. These two methods were adopted to perform SU-8-based low-temperature bonding at wafer level and with high precision. The bonding shear strengths reach 2-26 MPa when the bonding temperature varied from 60°C to 1401°C. View full abstract»

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  • Fabrication and Patterning of Magnetic Polymer Micropillar Structures Using a Dry-Nanoparticle Embedding Technique

    Page(s): 131 - 139
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    Previously, solvent casting techniques have been used for the fabrication of magnetic polymer micropillar structures. These techniques provide very limited control over magnetic-particle placement, and particle agglomeration limits their use with highly viscous polymers such as polydimethylsiloxane. We report a new technique for the fabrication of magnetic polymer micropillars to overcome the aforementioned limitations. In this technique, magnetic micro-/nanoparticles are applied to a mold in their dry particulate state, omitting the need for the use of solvents. We demonstrate magnetic micropillars with uniform properties using high-viscosity polymers and iron nanoparticles. We show that simple modifications to the dry-nanoparticle embedding technique allow the embedding of other functional (nonmagnetic) particles inside the polymer micropillars, and we demonstrate patterning of the device. We present experimental results for the material composition, the magnetic properties, and the bending performance of our magnetic micropillar arrays. Compared to previously fabricated magnetic micropillars of similar dimensions and using lower magnitudes of externally applied magnetic fields and magnetic field gradients (286 mT, 41.45 mT/mm), our 8-μm-diameter 18-μm-high pillars produce an estimated maximum horizontal tip force of 0.33 ±0.08 μN, larger than the values previously reported. View full abstract»

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  • Mechanical Characterization of Polycrystalline and Amorphous Silicon Carbide Thin Films Using Bulge Test

    Page(s): 140 - 146
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    This paper aims at determining the mechanical parameters such as Young's modulus, Poisson's ratio, and intrinsic stress of polycrystalline and amorphous silicon carbide thin films using the bulge test. A suitable method for the bulge test of highly compressive amorphous SiC films was devised by developing tensile composite layers involving a highly tensile substrate layer. A setup suitable for use in high temperatures was developed to hold membrane chips mechanically for applying pressure. The center deflection was measured with optical interferometry. The bulge test was done on square and rectangular membranes in order to ascertain the Poisson's ratio and the exact Young's modulus of the material. The tests in this paper were conducted at room temperature. The tensile polycrystalline SiC films were obtained by low-pressure chemical vapor deposition (LPCVD) at 825°C, using monomethylsilane as the precursor. The amorphous SiC (a-SiC) films were deposited by plasma enhanced chemical vapor deposition (PECVD) process at a temperature of 870°C with silane and acetylene as precursors. Test chips were pressurized from outside the membrane cavity, and membrane deflection was measured for each pressure step. The poly-SiC layers indicated a Young's modulus of 280 GPa with a Poisson's ratio of 0.237. The Young's modulus of a-SiC films was found to be 232 GPa, but the Poisson's ratio could not be determined as we used a composite layer. A comparison with the existing literature values of Young's modulus was also done. View full abstract»

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  • Size-Controllable Monodispersed Microsphere Generation by Liquid Chopper Utilizing PZT Actuator

    Page(s): 147 - 151
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    This paper describes a novel microfluidic method to prepare monodispersed water-in-oil (W/O) microspheres utilizing a piezoelectric actuator. In the main channel, a dispersed phase stream becomes focused and stabilized. In the side channels, oscillating streams are generated by the piezoelectric actuator and flow to the main channel to pinch off the focused stream to form a liquid chopper. By changing the frequencies of the liquid chopper, the size of the W/O microspheres can be successfully controlled in the range of 78.55 - 185.63 μm with very good uniformity (lower than 5% of the coefficient of variation). The present method has the advantages over conventional methods such as hydrodynamic flow focusing and T-junction. The proposed chopper method presents good sphericity, no satellite droplets, and size control of the microspheres. View full abstract»

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  • A Microcalorimeter Integrated With Carbon Nanotube Interface Layers for Fast Detection of Trace Energetic Chemicals

    Page(s): 152 - 162
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    Detection of trace explosives is still a challenging task because of the extremely low vapor concentrations. This paper reports a new microcalorimeter for detection of trace explosives with low detection limit and fast detection rate. The microcalorimeter consists of a suspended micromembrane with integrated heaters and thermistors and a carbon nanotube (CNT) interface layer in-situ synthesized on the membrane surface. Due to the large surface areas, the CNT interface layer improves adsorption to target chemical molecules. By operating the microcalorimeter in differential scanning calorimetry mode and differential thermal analysis mode, trace chemical detection is achieved through heating the adsorbed chemicals to deflagration and measuring the induced thermal response features and the total heat. The microcalorimeter is verified by explosive detection, and an equivalent limit of detection of 2.6 pg has been achieved by extrapolating the measurement results. Theoretically, detection is distinguishable upon 10-s fast exposure to saturated explosive vapors. These preliminary results demonstrate the ability of the microcalorimeter in detection of trace energetic chemicals. View full abstract»

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  • Fabrication and Characterization of Micromachined Piezoelectric T-Beam Actuators

    Page(s): 163 - 169
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    This paper presents a monolithically fabricated microelectromechanical piezoelectric cantilever beam with a T-shaped cross section capable of in-plane and out-of-plane displacements and sensing. High-aspect-ratio T-beams are achieved by direct micromachining of bulk lead zirconate titanate (PZT-4) via reactive ion etching of 65- μm-deep features. Electrodes deposited on the top and bottom web and flange regions of the T-shaped structure allow in-plane and out-of-plane motion actuation and sensing. The T-beam structures were tested for in-plane and out-of-plane tip displacements, out-of-plane blocking force, and impedance response. These results are explained using analytical models that predict static deflection, blocking force, and resonance frequency. Nine prototype micromachined T-beams are fabricated that achieve up to 129 μm of out-of-plane displacement, 11.6 μm of in-plane displacement, and 700 μN of out-of-plane blocking force. 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