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This paper reports on the steps that happen after the release of strained microhooks from silicon substrates. The application is automated microassembly of electronic circuits using clips that grasp microscale (< 200 micron diameter) conductive fibers. We developed an integrated, photoresist-based thermal release structure that allows the first direct observations of the release process outside the etch chamber. High speed camera video (4200 frames/s) shows the cantilevers release in an order determined by thermal diffusion, with groups of ~1200 micron long cantilevers releasable at 100 Hz. Side-view video is analyzed to show that the height of the graspable region is approximately half the hook length.
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This content will become publicly available on June 1, 2026
Thermally switchable tethers for rapid release of strained microstructures
Not AvailableThis paper reports on thermally switchable tethers that control the rapid release of strained microhooks from silicon substrates. Applications include automated microassembly of electronic circuits using clips that grasp microscale (<200 micron diameter) conductive fibers, as well as assembly of microdevices onto heat-sensitive materials by grasping. We developed an integrated, photoresist-based thermal release structure that allows the first direct observations of the release process outside the etch chamber. High speed camera video (4200 frames/s) shows the cantilevers release in an order determined by thermal diffusion, with groups of ~ 1200 micron long cantilevers releasable at 100 Hz. Side-view video is analyzed to show that the height of the graspable region is approximately half the hook length. The thermally isolated release method prevents the microhooks from heating, making it potentially useful for grasping heat-sensitive polymeric and biological materials.
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- Award ID(s):
- 2309482
- PAR ID:
- 10658827
- Publisher / Repository:
- Springer
- Date Published:
- Journal Name:
- Journal of Micro and Bio Robotics
- Volume:
- 21
- Issue:
- 1
- ISSN:
- 2194-6418
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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