The fluid-flow device (100) of the invention comprises a stack (30) covered by a closure wafer (20), said stack (30) comprising a support wafer (36), a layer of insulating material (34), and a silicon layer (32). The closure wafer (20) and/or said silicon layer (32) are machined so as to define a cavity...http://www.google.de/patents/US7311503?utm_source=gb-gplus-sharePatent US7311503 - Micromachined fluidic device and method for making same
