Studies On The Fabrication Technology For Producing Nickel Micro-mold By Micro-electroforming

Polymer microfluidic chips have many advantages for performing chemical and biological assays including low cost, reduced sample and reagent consumption, inexpensive fabrication due to mass production. In the past years, polymer microfluidic chips have attracted enormous interests as they open up the road to a high-volume production of disposable microfluidic devises. Nickel micro-mold has been widely used for fabrication polymer microfluidic chips by hot embossing or inject-molding methods with the advantage of long lifetime. The conventional technology for fabrication of nickel micro-mold is tedious. In this paper, the fabrication technology for producing nickel micro-mold was developed. In chapter 1, the manufacturing technologies for fabricating polymer microchips arereviewed.In chapter 2., the technology for fabricating microstructure using SU-8 negative photoresist by using UV lithography was optimized. MicroChannel with high depth has been fabricated on SU-8 photoresist layer.In chapter 3, a novel fabrication process for fabricating nickel micro-mold was developed. The fabrication process includes four steps: electroetching with large current, electropolishing, electroetching again and electroforming. The contact area between the nickel structures electroformed and the nickel substrate are increased. The impurities on the nickel surface is cleaned and the strength of the nickel structures on the nickel substrate has been improved. By using this technology, high strength nickel micro mold has been fabricated in a short time.