Abstract
There have been technical limitations to manufacture microstructures due to difficulty of demolding during replication process of high aspect ratio microstructure in mass production technologies. In the present study, the fabrication of a novel sacrificial micro mold insert and powder injection molding process using such a micro mold insert is proposed and developed. It utilizes a synchrotron radiation to fabricate the shape of polymer based sacrificial mold inserts and then these mold inserts were exposed at X-ray once more to adjust its solubility. This second X-ray exposure facilitates dissolving of mold inserts instead of demolding process which have difficulties like pattern collapses or defects in case of precise replication process. In this manner, severe problems of demolding process in conventional mass production technologies can be efficiently overcome. To verify the usefulness of the proposed technique, polymer based micro mold inserts with several tens of micrometer sized structure for piezoelectric sensor applications were fabricated using X-ray micromachining process radiated synchrotron. The solubility of mold inserts were optimized by the second X-ray exposure without an X-ray mask and then subsequent powder injection molding process was utilized with a piezoelectric based material. Finally, piezoelectric ceramics with micrometer-scale and high aspect ratio of 5 were successfully fabricated, verifying that the present sacrificial mold system is useful for the precise replication process such as the fabrication of microstructure with high aspect ratio or complicated structure.
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Acknowledgments
This research was supported by a grant from the Center for Advanced Materials Processing (CAMP) of the twenty-first Century Frontier R&D Program funded by the Ministry of Knowledge Economy (MKE), Republic of Korea and the experiments at Pohang Light Source (PLS) were supported in part by the Ministry of Education, Science and Technology and POSTECH.
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Kim, J.H., Choi, SY., Jeon, JH. et al. Manufacture of a micro-sized piezoelectric ceramic structure using a sacrificial polymer mold insert. Microsyst Technol 19, 343–349 (2013). https://doi.org/10.1007/s00542-012-1590-1
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DOI: https://doi.org/10.1007/s00542-012-1590-1