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Recent advancements in additive manufacturing such as Direct Write Inkjet printing introduced novel tools that allow controlled and precise deposition of fluid in nano-liter volumes, enabling fabrication of multiscale structures with submillimeter dimensions. Applications include fabrication of flexible electronics, sensors, and assembly of Micro-Electro-Mechanical Systems (MEMS). Critical challenges remain in the control of fluid deposition parameters during Inkjet printing to meet specific dimensional footprints at the microscale necessary for the assembly process of microscale structures. In this paper we characterize an adhesive deposition printing process with a piezo-electric dispenser of nano-liter volumes. Applications include the controlled delivery of high viscosity Ultraviolet (UV) and thermal curable adhesives for the assembly of the MEMS structures. We applied the Taguchi Design of Experiment (DOE) method to determine an optimal set of process parameters required to minimize the size of adhesive printed features on a silicon substrate with good reliability and repeatability of the deposition process. Experimental results demonstrate repeatable deposition of UV adhesive features with 150 μm diameter on the silicon substrate. Based on the observed wettability effect of adhesive printed onto different substrates we propose a solution for further reduction of the deposit-substrate contact area for microassembly optimization.
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This content will become publicly available on December 13, 2025
Heat-Depolymerizable Tethers for Microelectromechanical System Assembly
Microelectromechanical systems (MEMS) assembly into packages that interface with the environment is critical in electronic sensor applications ranging from soft biomedical systems to telecommunications. This article presents a novel process using heat-depolymerizable polyethylene carbonate (QPAC-25) as a sacrificial tether, and demonstrates it for assembling waferbound MEMS onto wires. The assembly mechanism is thermal removal of the tether, allowing a strained layer to pop up from the substrate and make electrical and mechanical contact with the wire. We detail the QPAC-25 fabrication procedures, characterize the relationship between QPAC-25 thickness and spin speed and determine a route to pattern QPAC-25 without a metal hard mask or photosensitizers
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- Award ID(s):
- 2309482
- PAR ID:
- 10565613
- Publisher / Repository:
- IEEE
- Date Published:
- Journal Name:
- Journal of Microelectromechanical Systems
- ISSN:
- 1057-7157
- Page Range / eLocation ID:
- 1 to 3
- Subject(s) / Keyword(s):
- MEMS polymer patterning sensor packaging sacrificial layer photolithography
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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