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We present the design and validation of a micromachined gripper array that enables reliable transmission of forces of at least 14 mN. The gripper is constructed with polycrystalline silicon (polysilicon), a brittle material, and is compatible with polysilicon surface micromachining. Two ingressive snap-and-lock array designs are presented. After developing design guidelines, it is shown that the first gripper array is functional. However, a risk remains that the gripper array rather than the tensile bar that it grips in its intended application fails. Therefore, an improved geometry is designed and it is shown that it is robust with respect to failure. Scanning confocal Raman imaging directly confirms that the local peak tensile stresses in the robust gripper array are approximately 50% of the lower bound material strength, and also resolves a 25% stress variation across the array.

We have fabricated, tested and analyzed the reliability of Pt- and RuO2-coated ohmic microrelays in ultra-high purity gas environments. RuO2-coated relays could survive 3 × 108 contact cycles without electrical degradation, while Pt-coated devices degraded after 105 cycles. Thermally actuated microrelays were fabricated using a process that employed a polysilicon surface-micromachined substructure. After releasing the devices, just a few blanket metal depositions were required to create the different coatings. This method allowed direct comparisons between different coating materials, and was enabled by a self-aligned shadow mask that provides electrical isolation between different traces. Testing was performed in a clean environment achieved through in situ ultra-high vacuum bakeouts, chamber cooling to

A new nanoscale tension testing platform with on-chip actuation and the unique capability for nanoscale mechanical characterization of highly deformable and strong nanostructures is presented. The specimen force and extension measurements are based on optical imaging, supported by digital image correlation, which allows the resolution of 20 nm specimen extensions and force measurements better than 30 nN, without the use of high-resolution electron microscopy. The breakthrough of this nanomechanical testing platform is the ability to study the mechanical behavior of nanostructures subjected to a wide range of forces (30 nN–300 µN) and displacements (20 nm–100 µm), which are significantly beyond the limits of typical surface micromachined MEMS with on-chip actuators, such as comb-drives and thermal actuators. The utility of this device in experimental nanomechanics is demonstrated by investigating the mechanical behavior of electrospun polyacrylonitrile nanofibers with diameters of 200–700 nm subjected to strains as high as 200%. The mechanical property measurements were compared to and agreed well with off-chip measurements by an independent testing method, which validates the capability of this on-chip testing platform to characterize strong and highly ductile nanomaterials.

We propose and demonstrate a microfabrication processing sequence that enables wafer-scale singulation, release and subsequent processing of microelectromechanical devices. This sequence significantly reduces handling of individual dice compared with more conventional post-processing. Other advantages include faster processing and potentially higher yield. The yield after packaging was 100% on 12 microrelay devices that were processed according to the sequence, including a metallization step after release. The reliability was better than typical compared with previous tests for these devices. This processing sequence is also applicable to nanoelectromechanical devices, enables a direct interface to microfluidic devices, and also makes it possible to manufacture chips of arbitrary shape.