Microvalve
Microvalves are valves whose dimensions are in the micrometer range . Microvalves are important components of microfluidics and are also used in microsystems .
Structure, function and application
Microvalves are mostly built on the basis of monocrystalline silicon (mostly 4-inch or 6-inch wafers , that is, smaller than they are used in semiconductor technology ). Channels are introduced into and through the substrate, for example by anisotropic etching of the silicon in a potassium hydroxide solution .
A typical functional principle is the control of the flow of flow via a micromechanically movable plunger that can close the flow channel. The deflection of the plunger can be driven, for example, by means of a stiffened silicon membrane that carries the plunger (can also be manufactured as a single component) and by a piezoceramic . As a result, a flow path can be actively opened and closed.
Due to their small dimensions, microvalves can be integrated very well into portable devices and compact systems, which creates completely new application possibilities, e.g. B. pilot valve for industrial pneumatics, quick release valve for blood pressure measurement , control valve for miniaturized flow sensors , control of microfluidic bioanalytical systems.
Web links
- Fraunhofer IZM (Ed.): Micro valve . 2007. Retrieved Feb. 19, 2009.
Individual evidence
- ↑ A strong memory. May 2, 2019, accessed June 14, 2019 .