Papers by Author: Chi Wei Wu

Abstract: The process of micro-powder blasting is the high speed gas flow which mixed the micro-particle and gas to impact the brittle substrate by the specialized nozzle. This paper combined various diameters Al2O3 eroding particle with a novel masking technique to fabricate the pattern channels in soda glass with a width to 2000 μm and depth down to 1631 μm. The masking technology for fabricating microchannel is consisted by the combination of two polymers: 1) the elastic and thermal-curable poly-(dimethyl siloxane) (PDMS) for its erosion resistance and 2) the brittle epoxy resin SU-8 for its photosensitivity. This paper discusses the processing procedure by the different processing parameters (micro-powder impact pressure, the distance between nozzle and substrate, micro-powder size, and micro-powder impact time) to find the optimal process. The results show that the micro-powder size is the most important factor for the depth of microchannel of microfluidic chip. The surface roughness of microchannel of microfluidic chip is nearly 5-6μm.

Abstract: This study demonstrates the replication property and surface roughness for metal micro-mold that combines the replica molding (REM) and electroforming techniques. The micro-mold firstly uses the silicon wafer to fabricate the master mold by UV-LIGA method, and then uses the sputtering method to sputter the Ni element as the seed layer on the surface of master mold. The electroforming method manufactures the Ni mold insert from the master mold with seed layer. Finally, this study uses the PDMS material to replicate the micro-feature from the Ni mold insert by replica molding. This study indicates the replication property and surface roughness of different micro-feature shapes and sizes (concave and convex) for Ni mold insert and molded PDMS.