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This paper presents the study on displacement valveless micropump which is actuated by electromagnetic force on a permanent magnet embedded in PDMS diaphragm. The network channel of the present pump includes two inlets and one outlet channels forming an intersection in front of a pump chamber. Two designs of the pump with different structure of the inlet channels are investigated. One structure of the inlet is curved around the pump chamber (type I) and the other is straight channels (type II). Both types of pump are in one layer structure. The numerical simulation results show that Type I produces larger flow rate than that of Type II. However, at small deflection of the diaphragm, the difference in flow rates between two pumps is not much. Type I shows a clear advance pump performance in comparison with Type II when deflection becomes large. Type I has been fabricated by MEMS technology for experiment study. The fundamental characteristics of the pump have been validated. The flow rate of up to 1.2 mL/min was obtained at driven frequency of 30Hz and applied current of 35 mA.

The paper reports on characterization of piezoresistive coefficients and Seebeck effect of aligned single wall carbon nanotube (SWNT) forest film. The film was synthesized by water-assisted chemical vapour deposition (CVD), a process known as “super growth”. CNT film was condensed, manually maneuvered and conveniently patterned by EB lithography to form desirable shapes. The piezoresistive coefficient was found to be two times of that of conventional bulk silicon counterpart. Measurements on Seebeck effect of the thermocouple made of Au-CNT films showed an output voltage of 7.5µV/°C. These devices were fabricated on a same silicon substrate with a single CNT film.

This paper presents for the first time the design, fabrication and characterization of an ultra miniaturized novel 3-axis accelerometer with nanoscale piezoresistive sensing elements and read out circuits. It was developed using MEMS/NEMS machining and fabrication techniques. This sensor consists of a new sub-millimeter structure with seismic mass and combined cross-beam and surrounding beams. It can detect three components of linear acceleration simultaneously. The sensitivity could be enhanced significantly while miniaturizing the die size of sensor chip with aid of novel structure and nanoscale piezoresistors on the sensing beams. Therefore, this novel proposed sensor is showing good performance and smaller than other comparable miniaturized sensor structures reported thus far. The accelerometer is capable of measuring accelerations up to ±20g in the frequency bandwidth of 480Hz. Comparison of the obtained experimental results and finite element simulation shows good agreement.