Solid micromechanical valves fabricated with in situ UV-LIGA assembled nickel

In situ UV-LIGA assembled robust microcheck valves with large flow rates (>10 ml/s, displacement related), high-pressure support ability (>10 MPa) and high operational frequencies (>10 kHz) made of nano-structured nickel were presented in this paper. The microvalve consists of an array of 80 single microvalves to achieve the required flow rates. A novel in situ UV-LIGA process was developed for the fabrication. Test results show that the forward flow rate is about 19 ml/s under pressure of 90 psi. The backward flow rate is negligible. The loading/unloading test results show that the flow rates were repeated very well over a large range of tested pressure differences. The reliability of the valve is ensured by the low stress valve design and the robust nano-structured nickel material fabricated.