Valve-less diffuser micropumps fabricated using thermoplastic replication

Abstract This paper presents valve-less diffuser micropumps fabricated using thermoplastic replication. Thermoplastic replication is very suitable for a valve-less diffuser pump due to its simple planar geometry. Two different thermoplastic replication methods have been tested: hot embossing and injection molding. We use 0.1 and 0.2 mm deep precision-milled brass mold inserts and 20 and 80 μm deep microelectroformed nickel mold inserts defined from deep reactive ion etched (DRIE) silicon wafers. For the injection molding a commercially available compact disc injection-molding machine (Toolex Alpha MD100) is used to fabricate the diffuser micropumps. The cycle times are extremely short, less than 10 s per disc, and one properly fabricated nickel mold insert can be used to fabricate more than 10 000 plastic discs. The plastic material cost is about 5 cents per disc. Tested pumps reach a maximum volume flow of 1.2 ml min−1 and a maximum pump pressure of 16 kPa.

[1]  W. Menz,et al.  Microfluidic components in LIGA technique , 1994 .

[2]  Göran Stemme,et al.  The first valve-less diffuser gas pump , 1997, Proceedings IEEE The Tenth Annual International Workshop on Micro Electro Mechanical Systems. An Investigation of Micro Structures, Sensors, Actuators, Machines and Robots.

[3]  G. Stemme,et al.  Micromachined flat-walled valveless diffuser pumps , 1997 .

[4]  Maria Chiara Carrozza,et al.  A fluid handling system for a chemical microanalyzer , 1996 .

[5]  G. Stemme,et al.  A valveless diffuser/nozzle-based fluid pump , 1993 .

[6]  W. Bacher,et al.  Micropump manufactured by thermoplastic molding , 1994, Proceedings IEEE Micro Electro Mechanical Systems An Investigation of Micro Structures, Sensors, Actuators, Machines and Robotic Systems.

[7]  Analytical Characterisation of Piezoresistive Square Diaphragm Silicon Microphone , 1996 .