Design and Fabrication of Microfluidic Devices: MOSFET & Capacitor

Microfluidic devices, based on silicon, are fabricated by photolithography, wet chemical etching with focus on an liquid conduction channel n-channel depletion MOSFET and a silica-liquid dielectric capacitor. Masks for both devices were designed with AutoCAD and printed on transparencies. Fabrication on p-<100> 4" Si wafers were executed and the devices were marginally characterized due to complications. The gate channel for the liquid FET (LFET) were set to four-sizes, which are 250μm, 500μm, 750μm an 1000μm. The liquid capacitor (LCap) size was limited to only two, for lack of space on the wafer. A variety of processes were used to fabricate these devices. Tests show feasibility of the idea but proves process and process parameter control is extremely important and critical.