Simple Fabrication Method of Micro-Fluidic Devices with Thick Resist Flow Paths Designed Arbitrarily Using Versatile Computer Aided Design Tools

Abstract

AbstractA simple and easy fabrication method of micro-fluidic devices using only single lithography processes was proposed. Thick resist patterns printed using a simple and handmade contact-lithography tool were directly used as flow-path patterns. Because pattern widths were as large as 50–200 μm, low-cost film reticles were applicable. Accordingly, various flow-path shapes were designed arbitrarily using a versatile computer aided design tool, and easily obtained in very quick turn-around times at very low costs. The sidewalls of flow paths were controlled almost vertical using long-wavelength exposure light. The flow paths formed on a silicon wafer chip were easily capped by sandwiching them between a vessel and lid plates using bolts and nuts. Even when two colored waters were simultaneously injected from the two inlet ports of a swirl-type micro-mixer, they did not leak at all in spite of such simple assemblies. The new fabrication method of micro-fluidic devices using thick resist patterning will be useful for various applications.KeywordsMicro-fluidic deviceLithographyContact exposureThick resistBlue filterVertical sidewallComputer aided design