XUROGRAPHIC MICROWIRE INTEGRATION TECHNIQUE FOR LAB ON CHIP APPLICATIONS

Abstract

Many functions in a lab-on-a-chip device such as heating, electrochemical sensing and electrophoresis require integration of microelectrodes. However, conventional techniques for microelectrode integration are either requiring expensive facilities, cleanroom environment or insufficient in resolution and microelectrode thickness. Microwires have also been integrated into LOC devices as microelectrodes. They are commercially available in a diversity of material. and diameter, with industrial production standard and mechanical strength comparable to bulk metal, which make them ideal candidate for microelectrode. Nonetheless a technique to integrate these microwires into complicated microelectrode patterns has not yet been developed. In this thesis, two microwire integration techniques based on xurography are developed for elastomer and rigid polymer. Copper, silver, platinum, carbon and Ni-Cr alloy microwires down to 15 µm with minimum spacing of 150 µm and controllable position in the height direction are successfully integrated. The microwire electrode can also be suspended in the middle of the microchannel with desired length and angle. Various applications are presented to demonstrate the versatility of the xurographic microwire integration process.