Novel characteristics of multifunctional fluid filter fabricated by high energy SR lithography

Although many advantages of microfluidics are recognized there are some problems to overcome, such as shortage of throughput, high pressure loss and limitation for large scale integration. These problems are caused by conventional planar structure of microfluidics and fabrication technique of micro channel. To overcome these problems, we newly proposed vertical fluid flow operation using fluid filter. Vertical fluid flow operation is performed by using reservoirs, which were set in the vertical direction, and the fluid filter separates them. The CFD analysis using CFD software "FLUENT" was conducted to examine the feasibility and fluid flow property of the vertical fluid flow operation for two kinds of filter material, PTFE and PMMA. Next, we have investigated properties of liquid mixing, which occurs during the transportation of liquid through the fluid filter. The fabrication of the fluid filter was conducted with deep X-ray lithography using energy region from 5 keV to 12 keV. The irradiation of the X-ray to PMMA sheets was conducted with LIGA beamline (BL2).