Membrane microfluidic valve and process for manufacturing a membrane microfluidic valve

A microfluidic device comprising:

• a substrate;
• a first layer of polymeric material;
• a second layer of polymeric material, the second layer arranged between the substrate and the first layer;
• and
• a microfluidic valve, including:
• a first microfluidic conduit and a second microfluidic conduit in the first layer;
• a chamber in the first layer, the chamber separating the first microfluidic conduit from the second microfluidic conduit, a portion of the first microfluidic conduit extending in to the chamber;
• an opening in the second layer that forms a recess at a surface of the substrate, the recess including sidewalls formed by the second layer and a base formed by the substrate;
• a membrane located between the first and second layers and over the opening, the membrane including polymeric material and particles of magnetic material, the membrane fluidly isolating the recess from the first microfluidic conduit, the second microfluidic conduit, and the chamber;
• a wall located between the first microfluidic conduit and the chamber, the wall having an end that rests against the membrane, the wall and the membrane being configured to fluidly isolate the first microfluidic conduit from the chamber when the end of the wall rests against the membrane, the wall delimiting a convex shape of the portion of the first microfluidic conduit such that the portion of the first microfluidic conduit is surrounded on at least two sides and an end by the chamber, the wall being surrounded on at least two sides and an end by the chamber;
• and
• an actuator device configured to apply a magnetic field to the membrane to cause the membrane to move away from the end of the wall and allow the first microfluidic conduit and the chamber to be in fluid communication with each other.

A process comprising:

• in a first layer of polymeric material, forming a first microfluidic conduit, a second microfluidic conduit, and a chamber that are adjacent to each other in a active region, the chamber separating the first microfluidic conduit from the second microfluidic conduit, a portion of the first microfluidic conduit extending in to the chamber, the first microfluidic conduit being separated from the chamber by a u-shaped wall in the active region such that the portion of the first microfluidic conduit is surrounded on at least two sides and an end by the wall, the wall being surrounded on at least two sides and an end by the chamber, the first layer having a first surface and a second surface that is opposite the first surface;
• forming a first channel in the first layer, the first channel being in fluid communication with the first microfluidic conduit, the first channel extending through the first surface of the first layer;
• forming a second channel in the first layer, the second channel being in fluid communication with the second microfluidic conduit, the second channel extending through the first surface of the first layer, the first channel being separated from the second channel by the first microfluidic conduit, the second microfluidic conduit, and the chamber;
• forming a recess in a second layer of polymeric material;
• placing a membrane between the second surface of the first layer and the second layer, the membrane including polymeric material and particles of magnetic material;
• and
• bonding the first layer to the second layer with the recess in a position corresponding to the active region, the membrane fluidly isolating the recess from the first microfluidic conduit, the second microfluidic conduit, and the chamber.