Title: Nickel electroforming of 3D microstructure by using BPR100 photoresist mould

Authors: Xue Yong Wei, Chen Han Lee, Kyle Jiang

Addresses: Department of Manufacturing and Mechanical Engineering, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK. ' Department of Manufacturing and Mechanical Engineering, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK. ' Department of Manufacturing and Mechanical Engineering, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK

Abstract: BPR100 photoresist is a thick negative tone resist with a single-pin film thickness ranging from 40 to 130 µm. It has been widely applied to plating and etching processes used in Wafer Level Package (WLP). However, its application as mould in electroforming Three Dimensional (3D) microstructure for Micro Electromechanical Systems (MEMS) application has not yet been reported. The process of nickel electroforming of microgears by using BPR100 photoresist mould was thereby studied and is reported in this paper. The electroformed nickel gear was respectively characterised using a Scanning Electron Microscope (SEM) and an Atomic Force Microscope (AFM). Results showed that a pits-free microsgear was achieved with an average surface roughness ranging from 20 to 68 nm and its geometric structure was well shaped. Through this study, it was found possible to electroform 3D microstructure of good quality by using BPR100 photoresist mould.

Keywords: nickel electroforming; three dimensional microstructure; 3D microstructure; BPR100 photoresist moulds; nanomanufacturing; wafer level packages; WLP; microelectromechanical systems; MEMS; microgears; nickel gears; surface roughness.

DOI: 10.1504/IJNM.2007.014569

International Journal of Nanomanufacturing, 2007 Vol.1 No.4, pp.499 - 505

Published online: 16 Jul 2007 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article