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A novel type of single use bi-stable MEMS solid off-on switch based on metal bridge igniter is described and its performance test results are presented. The switch mechanically connects a couple of comb electrodes which belong separately to different metallic lines. Switching between the two stable states (off and on) is accomplished by a voltage pulse supplied by an energy storage capacitance through a metal bridge igniter above the electrical lines to be connected. The switch can be driven by external signal and its predicted lifetime is very long, therefore the switch can be used for long term store systems.

In the present work, the effects of preloading on the tensile properties of braided polyarylate fiber ropes were investigated experimentally. Four kinds of samples with different pitch lengths were tested with designed preload levels. The deformation responses of the ropes were captured using digital image correlation (DIC) and micro-computed tomography (micro-CT). It is shown that the nonlinearity in the mechanical behavior of the ropes can be almost eliminated post-preloading with one cyclic loading, and the transverse strains are much greater than the longitudinal strains due to the compaction of rope structure because of the spiral interlaced path of braid yarns. The rope with shorter pitch length (larger braid angle) has larger longitudinal strain and smaller transverse strain due to the higher yarn crimp rate and tighter yarns, respectively. The preload level is the most important parameter for preloading. The chord modulus of the ropes reached an optimum level at the preload level of 40% break load, and the tensile strength can be increased by 15% at the preload level of 50% break load. Moreover, the stability of the tensile properties could be accelerated at the higher preload level. Consequently, preloading is vital to improve the tensile properties of braided polyarylate fiber ropes, with a preload level at least of 40% break load and 10 cyclic loadings.

This article mainly focuses on the reliability of micro-spring, which as a typical component of MEMS device, applies electrodeposited nickel material and is fabricated by LIGA process, being used under the circumstances like transporting and restoring which may induce shock and crash. Griffith theory of brittle fracture and Abaqus FEA simulation software are applied for analyzing the probable failure modes of the micro-spring as overloaded. And the principle of elastic deformation, energy-time and displacement-time variation curves are given by three groups of simulation experiments. It proves to be one novel method to evaluate the reliability and accelerate exposing the failure mode of these MEMS components under dynamic circumstances in short period. After comparison, this method is proved reliable for analyzing and providing evidence for enhancing the reliability of the micro-spring, also improving the performance in micron size.

In this paper, we present an all-in-one wafer-level solution for MMIC (monolithic microwave integrated circuit) automatic testing. The OSL (open short load) two tier de-embedding, the calibration verification model, the accurate PAE (power added efficiency) testing, and the optimized vector cold source NF (noise figure) measurement techniques are integrated in this solution to improve the measurement accuracy. A dual-core topology formed by an IPC (industrial personal computer) and a VNA (vector network analyzer), and an automatic test software based on a three-level driver architecture, are applied to enhance the test efficiency. The benefit from this solution is that all the data of a MMIC can be achieved in only one contact, which shows state-of-the-art accuracy and efficiency.