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| 2. |
- Braun, Stefan, et al.
(author)
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MEMS single-chip 5x5 and 20x20 double-switch arrays for telecommunication networks
- 2007
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In: IEEE 20th International Conference on Micro Electro Mechanical Systems, 2007. MEMS. - New York : IEEE. - 9781424409518 - 1424409519 ; , s. 811-814
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Conference paper (peer-reviewed)abstract
- This paper reports on a microelectromechanical switch array with up to 20x20 double switches and packaged on a single chip and utilized for main distribution frames in copper-wire networks. The device includes 5x5 or 20x20 allowing for an any-to-any interconnection of the input line to the specific output line. The switches are on an electrostatic S-shaped film actuator with the contact moving between a top and a bottom electrode. device is fabricated in two parts and is designed to assembled using selective adhesive wafer bonding in a wafer-scale package of the switch array. The 5x5 switch arrays have a size of 6.7x6.4mm(2) and the arrays are 14x10 mm(2) large. The switch actuation for closing/opening the switches averaged over an array measured to be 21.2 V / 15.3 V for the 5x5 array 93.2 V / 37.3 V for the 20x20 array. The total impedance varies on the 5x5 array between 0.126 Omega 0.564 Omega at a measurement current of 1 mA. The resistance of the switch contacts within the 5x5 array determined to be 0.216 Omega with a standard deviation 0. 155 Omega.
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| 3. |
- Braun, Stefan, et al.
(author)
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MEMS single-chip microswitch array for re-configuration of telecommunication networks
- 2006
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In: 2006 European Microwave Conference. - New York : IEEE. - 9782960055160 ; , s. 315-318
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Conference paper (peer-reviewed)abstract
- This paper reports on a micro-electromechanical (MEMS) switch array embedded and packaged on a single chip. The switch array is utilized for the automated re-configuration of the physical layer of copper-wire telecommunication networks. A total of 25 individually controllable double-switches are arranged in a 6.7 x 6.4 mm(2) large 5x5 switch matrix allowing for any configuration of independently connecting the line-pairs of the five input channels to any line-pair of the five output channels. The metal-contact switch array is embedded in a single chip package, together with 4 metal layers for routing the signal and control lines and with a total of 35 I/O contact pads. The MEMS switches are based on an electrostatic S-shaped thin membrane actuator with the switching contact bar rolling between a top and a bottom electrode. This special switch design allows for low actuation voltage (21.23 V) to close the switches and for high isolation. The total signal line resistances of the routing network vary from 0.57 Omega to 0.98 Omega. The contact resistance of the gold contacts is 0.216 Omega.
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| 4. |
- Braun, Stefan, et al.
(author)
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Robust trimorph bulk SMA microactuators for batch manufacturing and integration
- 2007
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In: The 14th IEEE International conference on Solid-State Sensors, Actuators and Microsystems Conference & EUROSENSORS XXI (IEEE TRANSDUCERS 2007). - : IEEE conference proceedings. - 9781424408412 ; , s. 2191-2194
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Conference paper (peer-reviewed)abstract
- This paper introduces the concept of batch micrufabrication and electrical contacting of bulk SMA nticroactuators. This concept addresses technical solutions for the main challenges related to using SMA actuators such as the necessary mechanical bias force, the difficult electrical contacting and the high power needed for actuation. We report on initial SMA-dielectric-metal trimorph test structures and their characteristics. The bias force is provided by a dielectric layer and the electrical contacting of the bulk SMA is avoided using indirect electrical heating via an additional metal layer. Three nun long beams can provide several hundreds of mu N and deflect several hundreds of mu m. The actuation power is reduced approx. 2.5 times compared to direct heating schemes.
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| 5. |
- Braun, Stefan, et al.
(author)
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Small footprint knife gate microvalves for large flow control
- 2005
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In: The 13th International Conference on Solid-State Sensors, Actuators and Microsystems conference (IEEE TRANSDUCERS 2005). - NEW YORK : IEEE conference proceedings. ; , s. 329-332
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Conference paper (peer-reviewed)abstract
- This paper introduces the first area-optimized micromachined knife gate microvalve. In comparison to recent microvalves the pressure-flow performance is increased using out-of-plane actuators and an out-of-plane orifice. Three different actuator-gate designs and their fabrication are described. The valve features integrated therinal silicon/aluminum bimorph actuators where the aluminum layer forins the resistive heater as well as the bimorph material. The characterization of the actuators and of the pressure-flow perfon-nance is presented. The valve allows a flow change of Delta Q=3.4 1/min at 100 kPa on an active chip area of only 2.3 x 3.7 mm(2).
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| 6. |
- Braun, Stefan, et al.
(author)
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Smart individual switch addressing of 5×5 and 20×20 MEMS double-switch arrays
- 2007
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In: TRANSDUCERS and EUROSENSORS '07 - 4th International Conference on Solid-State Sensors, Actuators and Microsystems. - : IEEE. - 9781424408429 - 1424408423 ; , s. 153-156
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Conference paper (other academic/artistic)abstract
- This paper presents a smart row / column addressing scheme for large MEMS rnicroswitch arrays, utilizing the pull-in / pull-out hysteresis of their electrostatic actuators to efficiently reduce the number of control lines. Single-chip 20 x 20 double-switch switch arrays with individually programmable 400 switch elements have been fabricated and the smart addressing scheme was successfully evaluated. The reproducibility of the actuation voltages within the array is very important for this addressing scheme and therefore the influence of effects such as isolation layer charging on the pull-in voltages has also been investigated.
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| 7. |
- Clausi, D., et al.
(author)
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Microactuation utilizing wafer-level integrated SMA wires
- 2009
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In: Proceedings of the IEEE International Conference on Micro Electro Mechanical Systems. - 9781424429783 - 9781424429776 ; , s. 1067-1070
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Conference paper (peer-reviewed)abstract
- This paper reports on the wafer-scale integration of pre-strained SMA wires to microstructured silicon devices and the performance of the microactuator prototypes. The overall goal is to obtain low cost microactuators having high work densities and a mass production compatible manufacturing, without having to deal with the inherently high costs of a pick-and-place approach or with the complex composition control and annealing process of sputtered NiTi films. Testing above the SMA transformation temperature shows repeatability in actuation of the fabricated structures, with net strokes of 170 ptm for the double cantilever actuators.
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| 8. |
- Clausi, Donato, et al.
(author)
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Reliability of Silicon Spring-biased SMA Microactuators
- 2012
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Conference paper (other academic/artistic)abstract
- This paper reports on the performance of Joule-heated shape memory alloy (SMA) microactuators on silicon MEMS.The actuators consist of pre-strained SMA wires connected to micromachined silicon structures by electroplatedfixtures. Response of the actuators upon long term cycling by electrical heating is evaluated. Measurements on a 4.5x 1.6 mm2 footprint device demonstrated excellent stability of the actuator, without any loss of performance over150·103 cycles. These actuators are potentially suited for industrial applications with stringent demands on actuationperformance, reliability, and cost.
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| 9. |
- Clausi, Donato, et al.
(author)
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WAFER-LEVEL MECHANICAL AND ELECTRICAL INTEGRATION OF SMA WIRES TO SILICON MEMS USING ELECTROPLATING
- 2011
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In: 24th IEEE International Conference on Micro Electro Mechanical Systems (IEEE MEMS 2011). - : IEEE conference proceedings. - 9781424496327 ; , s. 1281-1284
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Conference paper (peer-reviewed)abstract
- This paper reports on the wafer-level fixation and electrical connection of pre-strained SMA wires on silicon MEMS using electroplating, providing high bond strength and electrical connections in one processing step. The integration method is based on standard micromachining techniques, and it potentially allows mass production of microactuators having high work density. SEM observation showed an intimate interconnection between the SMA wire and the silicon substrate, and destructive testing performed with a shear tester showed a bond strength exceeding 1 N. The first Joule-heated SMA wire actuators on silicon were fabricated and their performance evaluated. Measurements on a 4.5 x 1.8 mm2 footprint device show a 460 μm stroke at low power consumption (70 mW).
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| 10. |
- Fischer, Andreas C., 1982-, et al.
(author)
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Wafer-level integration of NiTi shape memory alloy wires for the fabrication of microactuators using standard wire bonding technology
- 2011
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In: 24th International Conference on Micro Electro Mechanical Systems (MEMS), 2011 IEEE. - : IEEE. ; , s. 348-351
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Conference paper (peer-reviewed)abstract
- This paper reports on the first integration of SMA wires into silicon based MEMS structures using a standard wire bonder. This approach allows fast and efficient placement, alignment and mechanical attachment of NiTi-based SMA wires to silicon-based MEMS. The wires are mechanically anchored and clamped into deep-etched silicon structures on a wafer. The placement precision is high with an average deviation of 4 #x03BC;m and the mechanical clamping is strong, allowing successful actuation of the SMA wires.
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