A simplified microfabrication technology for production of nickel mold insert for replicating of plastic microfluidic chips

作者：Lu Chun Hua^*; Yin Xue Feng; Lu Ping

来源：Chinese Journal of Analytical Chemistry, 2007, 35(5): 767-771.

• microfluidic chips
• electroforming
• nickel mold insert
• SU-8 photoresist

A simple and inexpensive method to fabricate nickel mold insert for replicating of plastic microfluidic chips has been developed without the requirement of specialized equipments. A polished nickel plate was used as a substrate on which a thick SU-8 photoresist layer was coated. Conventional contact UV lithography was applied to pattern the thick SU-8 photoresist layer. After development, electroetching was conducted at a large current density of 16 - 30 A/dm(2) for 5 min to clean the nickel surface in the SU-8 recesses where unexposed SU-8 had been lifted up and to form 10 - 20 in depth of root structures for increasing the strength of the nickel insert electroformed later on. By using the fabricated SU-8 microstructure as a template and nickel substrate as an electrode supplying current, nickel mold insert with a sidewall slope of 83 and higher aspect ratio were successfully fabricated within 5 h in a conventional chemical laboratory. More than 500 polymethyl methyl acrylate ( PMMA) microfluidic chips have been replicated by hot-embossing. The chips have been used successfully for the separation of DNA fragments.

• 出版日期2007-5
• 单位浙江大学