A Multifluidic MEMS Microneedle

In this thesis, I will give an introduction of the development of microneedle. Several fabrication methods from other groups will be briefly presented, such as anisotropic wet etching method, buried microchannel method, double deep X-ray lithography method, and so on. Some basic concepts of microfluidics is introduced as a theory foundation.The microneedle fabricated in University of Notre Dame is based on triple anisotropic BOSCH etching. To satisfy the further experiment requirement, there are four microchannels on one chip which have different penetration depth. The microchannel has a rectangular cross section shape, 2.8 Ìøå_m in width, about 10 cm in length, and its depth can be determined by the etching time.Through the testing with water and air, the design and fabrication process are proved to be feasible. From the comparison of measured air flow rate and the simulated data in COMSOL, the experimental and simulated results match well within experimental error. The simulated water flow rate is less than 30 picoliters/s at small pressures.