A ball valve micropump in glass fabricated by powder blasting
We present the microfabrication and characterisation of a ball valve micropump in glass, which is magnetically actuated using the sinusoidal current of an external electromagnet. We employ the use of a simple powder blasting technology for microstructuring the glass substrates and fusion bonding for assembly of the multi-layered microfluidic chip. The use of a polymer membrane with embedded permanent magnet gives rise to a large actuation stroke, making the micropump bubble-tolerant and self-priming. The micropump exhibits a backpressure as high as 280 mbar and water flow rates up to 5 mL/min thanks to the large magnetic actuation force and the use of high-efficiency ball valves. The frequency-dependent characteristics are in excellent agreement with a hydrodynamic damped oscillator model.