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A three-axis piezoresistive accelerometer which has adjustable resolutions to three axes was developed using MicroElectroMechanical Systems (MEMS) technology. This sensor made of a heavy proof mass and four long beams is to obtain high resolutions by reducing resonance frequencies. Adjustable resolution with small cross axis sensitivity could be obtained by a three-dimensional sensor structure.

This paper presents an electro-thermally bimorph microgripper based on silicon-polymer laterally stacked structures and a method to optimized the fabricated device. The actuated displacement is enhanced due to the polymer constraint effect. Both the thermal expansion and apparent Young’s modulus of the constrained polymer blocks are significantly improved, compared with the no constraint one. The device consists of a serpentine-shape deep silicon structure with a thin film aluminum heater on the top and filling polymer in the trenches among the vertical silicon parts. The fabricated bimorph microgripper can operate in four modes and generates a large motion up to 15 μm. The simulated results are met the fabricated measurements. An optimized structure is proposed for decreasing the working temperature, power consumption but increasing the output displacement. The simulated results are showed that the output displacement is increased up to 550% and temperature profile improved considerably. This electro-thermally silicon-polymer opened and closed microgripper can be used in micro-robotics, micro-assembly, minimally invasive surgery, living cells surgery.

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The conventional first-principles density-functional theory (DFT) predicts a negative bandgap of the thermoelectric semiconductor Bi2O2Te, which needs to be corrected. To enable a higher-level precise calculation, in this report, we include the self-consistent on-site [Formula: see text] and inter-site [Formula: see text] interactions in our studies, the so-called [Formula: see text] method, and demonstrate that it significantly improves the description of excited states of Bi2O2Te. The on-site interactions of Te-p and O-p play an essential role and substantially improve the band gap of Bi2O2Te. Inter-site interaction between Bi-s, Bi-p, and O-p within the [Bi2O2] layer and between the intercalated Te layer and the [Bi2O2] layer further increases the band gap. Thermoelectric coefficient calculations show a significant Seebeck coefficient and the power factor in p-type doping, which originates from the intercalated Te layer.