One of the major difficulties faced by MEMS researchers today is the lack of data regarding properties of electroplated metals or alloys of which microstructures and microdevices are fabricated, especially in LIGA technology. These mechanical properties cannot be extrapolated from macro-scale data without experimental verification. Therefore, study on material properties of microfabricated structures is of vital importance to the development of LIGA technology and to its industrial applications. This paper reports an experiment scheme and UV-LIGA microfabrication technology to study the fracture toughness of nickel micro specimens. The devised testing mechanism demonstrated compatibility with the fabricated samples and capability of performing the desired experimentation by generating resistance-to-fracture values of the nickel specimens. The same experiment scheme and sample fabrication technology can be used in future work to study the fracture toughness values for LIGA fabricated samples in various metals and alloys.

One of the major difficulties faced by MEMS researchers today is the lack of data regarding properties of electroplated metals or alloys at micro-levels as those produced by the LIGA and the LIGA related process. These mechanical properties are not well known and they cannot be extrapolated from macro-scale data without experimental verification. This lack of technical information about physical properties at microscale has affected the consistency and reliability of batch-fabricated components and leads to very low rates of successful fabrication. Therefore, this material issue is of vital importance to the development of LIGA technology and to its industrial applications. The research work reported in this paper focuses on the development of a new capability based on design, fabrication, and testing of groups of UV-LIGA fabricated nickel microspecimens for the evaluation of fracture strength. The devised testing mechanism demonstrated compatibility with the fabricated samples and capability of performing the desired experimentation by generating resistance-to-fracture values of the nickel specimens. The average fracture strength value obtained, expressed with a 95% confidence interval, was 315 ± 54 Mpa. Further data acquisition, especially involving tensile specimen testing, and material analysis is needed to fully understand the implications of the information obtained.

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