ISSN:
1089-7623
Source:
AIP Digital Archive
Topics:
Physics
,
Electrical Engineering, Measurement and Control Technology
Notes:
Micromechanics, an emerging technology for sensor and actuator fabrication, has a large market potential that has already been exploited in the sensor area. Progress in actuators, devices that modify their environment and are fundamentally three dimensional, has been much more modest and is suffering from the availability of a fabrication tool with the necessary attributes. If the tool is based on photoresist technology, requirements include very large structure heights: in the millimeter range, for mask-defined prismatic photoresist shapes with flanks that differ from 90 degrees by less than 15 arc-seconds. Photoresist procedures that lead to these results are very different from their counterparts in the microelectronic industry. Thus, application is based on precast sheets of polymethyl methacrylate, PMMA, and solvent bonding followed by precision fly-cutting. Exposure is based on well-collimated x-ray sources, synchrotrons, with flux densities that can deposit 1,600 Joules per cubic centimeter in a finite time at the correct photoresist depth. Since PMMA has an absorption length that varies with photon energy, it is 100 micrometer at 3000 eV and increases to 1 cm at 20,000 eV, beamline and exposure designs center on transmission filters that control the low energy portion of the synchrotron spectrum. Since exposure latitude is large, overexposure by a factor of 15 is allowed, beamline and exposure design are relatively simple. Experiments via the Wisconsin machine, Aladdin, and the Brookhaven 2.6-GeV ring are being used to study the effectiveness issue of manufacturing with synchrotron radiation. Actuator test vehicles are linear and rotational magnetic micromotors with force outputs in the milli-Newton range. High energy exposures have produced large parts with submicron precision that are finding applications in ink jet printing and precision injection molding procedures. Both device types are unique to x-ray assisted processing. © 1996 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.1147379
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