Manufacturing and Characterization of a Ceramic Single-use Microvalve

Presented here and with foreseen utilization in space applications and other demanding applications, is the manufacturing and characterization of a ceramic single-use microvalve with the potential to be integrated in lab on a chips. A-3 mm diameter membrane was used as the flow barrier, and the opening mechanism was based on cracking the membrane by inducing thermal stresses on it with fast and localized resistive heating. Four manufacturing schemes based on high-temperature co-fired ceramic technology were studied. Three designs for the integrated heaters and two thicknesses of 40 and 120 μm for the membranes were considered, and the heat distribution over their membranes, the required heating energies, their opening mode, and the flows admitted through were compared. Furthermore, the effect of applying +1 and -1 bar pressure difference on the membrane during cracking was investigated. Thick membranes demonstrated unpromising results for low pressure applications since the heating either resulted in microcracks or cracking of the whole chip. Because of the higher pressure tolerance of the thick membranes, the design with microcracks can be considered for high-pressure applications where flow is facilitated anyway. Thin membranes, on the other hand, showed different opening sizes depending on heater design and, consequently, heat distribution over the membranes, from microcracks to holes with the sizes of 3-100% of the membrane area. For all the designs, applying +1 bar over pressure, contributed to bigger openings, whereas -1 bar pressure difference had this influence just for one of the designs and resulted in smaller openings for the other two. The energy required for breaking these membranes was a few hundred mJ with no significant dependence on design and applied pressure. The maximum sustainable pressure of the valve for the current design and thin membranes