Zhang Dacheng

A sensor platform based on piezoresistive cantilever

In this paper U-shaped as well as rectangular piezoresistive cantilever array have been designed and fabricated based on silicon micromachining technology. Single crystalline silicon is used as the piezoresistive material. The sensitivities and the noises of piezoresistive cantilevers were systematically investigated from both the theory and the experimental results. The minimum detectable deflections (MDD) of piezoresistive cantilever are calculated to be 0.3 nm for rectangular cantilever and 0.2 nm for U-shaped cantilever at a 6 V bias voltage and a 1000 Hz measurement bandwidth. Using polymer-coated cantilevers as a chemical sensor, its response to water vapor was tested by measuring its output voltage signals. The measurement shows that the sensor sensitivity is high and the response is quick.

Characteristics of Gas Flow within a Micro Diffuser/Nozzle Pump

英文摘要: The gas flow characteristics for various shapes of micro diffuser/nozzles have been experimentally investigated. The micro diffuser/nozzles with the lengths of 70 mu m, 90 mu m, 125 mu m and the taper angles of 7 degrees, 10 degrees, 14 degrees are designed and fabricated based on silicon micromachining technology for optimizing and comparing. The flat-wall diffuser/nozzle is 40 mu m x 5 mu m in depth and width. An experimental setup is designed to measure the gas flow rates under controlled temperature and pressure condition. Optimized values for the taper angle and the length of the diffuser/nozzle are experimentally obtained.

Selective parallel CRC computation schemes for RapidIO

RapidIO is a high-performance standard for embedded interconnections. Due to different ending alignments of RapidIO packets, the corresponding CRC computations should be adjustable. In this paper, two selective parallel computation schemes based on simplified intermediate value equations are proposed. Compared with the reference designs, the power dissipations can be reduced by more than 30% meanwhile better balances between the speeds and resource consumptions can be achieved.

Application of nano-crystalline silicon film in the fabrication of field-emission pressure sensor

A kind of filed-emission array pressure sensor is designed based on the quantum tunnel effect. The nano-crystalline silicon film is prepared by chemical vapor deposition (CVD) method, with the grain dimension and thickness of the film 3–9 nm and 30–40 nm. respectively. The nano-crystal-line silicon film is introduced into the cathode cones of the sensor, functioning as the essential emission part. The silicon nano phase is analyzed by HREM and TED, the microstructure of the single emitter and emitters array is inspected by SEM, and the field emission characteristics of the device are studied by an HP4145B transistor tester. The experimental results show that the measured current density emitted from the effective area of the sensor can reach 53.5 A/m2 when the exterior electric field is 5.6×105 V/m.