Method of forming seals for a microfluidic device

The present invention relates to microfluidic devices, and more particularly, to the sealing layers between with a device and a method of forming seals on a microfluidic device. A microfluidic device has a seal or other component between two adjacent layers. The seal or other component is formed of a sheet of material having a first thickness. The seal material has boss portions that have a second thickness greater than the first thickness. A plurality of holes are formed through the boss portion. A method for making the seal layer includes the step of thinning the seal material between a first film and a second film. Bosses are formed in the film. Holes are cut through the boss area. One film is removed from the seal material and the seal material is applied to a substrate. The seal material is cured to a substrate and the second film is removed from the seal material. Other components such as diaphragm may be formed using the above process without punching holes through the seal material.