Tài liệu Valve For Power Mems ppt

Umans Sponsorship ARO A micromachined valve is being developed that could be used as the gas fuel delivery valve for a power MEMS device.. The electrostatically-actuated valve is fabrica

A Micromachined Valve for Power MEMS

Personnel

X Yang (J Lang, M.A Schmidt, and S Umans)

Sponsorship

ARO

A micromachined valve is being developed that could

be used as the gas fuel delivery valve for a power

MEMS device The electrostatically-actuated valve is

fabricated through the aligned bonding of three silicon

wafers which have been patterned using DRIE A

mid-dle wafer forms the moving part of the valve which is

comprised of a boss supported by four thin tethers

Upon the application of a voltage between the boss and

either the upper or lower wafer, the boss will move

upward to open the valve or downward to seal the

valve against a polysilicon coated seal-ring The

polysil-icon provides a defined level of surface roughness

which helps to reduce valve sticking The valve has

been successfully operated to 10 atm inlet pressure with

actuation voltages between 100-200V Leak rates are

below the measurement capability

Fig 26: The three-layer microvalve.

Fig 27: A schematic cross section of the valve.

Fig 28: SEM images of the three layers of the microvalve, as well as

Fig 29: N2 flow-rate versus actuation voltage for the valve as a func-tion of inlet pressure.