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Recent advances in the development of microplasma devices fabricated in a variety of materials systems (Si, ceramic multilayers, and metal/polymer structures) and configurations are reviewed. Arrays of microplasma emitters, having inverted pyramidal Si electrodes or produced in ceramic multilayer sandwiches with integrated ballasting for each pixel, have been demonstrated and arrays as large as 30×30 pixels are described. A new class of photodetectors, hybrid semiconductor/microplasma devices, is shown to exhibit photoresponsivities in the visible and near-infrared that are more than an order of magnitude larger than those typical of semiconductor avalanche photodiodes. Microdischarge devices having refractory or piezoelectric dielectric films such as Al 2 O 3 or BN have extended lifetimes (∼86% of initial radiant output after 100 h with an Al 2 O 3 dielectric) and controllable electrical characteristics. A segmented, linear array of microdischarges, fabricated in a ceramic multilayer structure and having an active length of ∼1 cm and a clear aperture of 80 × 360 µm 2 , exhibits evidence of gain on the 460.3 nm transition of Xe + , making it the first example of a microdischarge-driven optical amplifier.

We have investigated magnetic actuation of hinged, surface micromachined structures. Electroplated magnetic material (Permalloy) is integrated with two types of hinged microstructures and the magnetic actuation process has been experimentally characterized. Under a given external magnetic field, the angular displacement of a hinged structure is determined by the volume of the magnetic material or by the stiffness of an auxiliary flexural loading spring. We have demonstrated parallel actuation of large arrays of hinged microstructures under a global (wafer scale) external magnetic field. The design rules for achieving a prescribed asynchronous actuation sequence among a group of microstructures have been determined to enable efficient parallel assembly of three-dimensional (3-D) microstructures. [347]

This paper presents results on the development and application of a three-dimensional (3-D) microstructure assembly technique-Plastic deformation magnetic assembly (PDMA). In PDMA, certain part of the microstructure to be assembled is plastically deformed by the magnetic force generated from the interaction between a magnetic material piece deposited on the microstructure and an external magnetic field. As a result, the entire microstructure can remain at a rest angle with respect to the substrate surface due to the plastic deformation. The amount of plastic deformation and the rest angle are found to be strongly dependent on the properties and the geometric parameters of the deformation region of the microstructure and also the magnetic material piece. A general design rule for PDMA has been given. PDMA is capable of batch-scale assembly. It has been successfully applied to fabricate novel micromachined devices with high yield and good controllability. As an example, the results of a novel vertical planar spiral inductor realized by the application of PDMA have also been presented in the paper.