Applications of Novel High-Aspect-Ratio Ultrathick UV Photoresist for Microelectroplating

Author

Staab, Matthias ; Greiner, Felix ; Schlosser, Michael ; Schlaak, Helmut F.

Author_Institution

Microsyst. Technol. Lab., Tech. Univ. Darmstadt, Darmstadt, Germany

Volume

20

Issue

4

fYear

2011

Firstpage

794

Lastpage

796

Abstract

The new acrylic photoresist named AZ 125 nXT is a serious option for low-cost high-aspect-ratio UV LIGA applications. It offers advantages compared to SU-8 like good adhesion to Si substrates, rapid processing, and easy removal after electroplating. Film thicknesses of 400, 800, and 1400 μm with an aspect ratio of 20 : 1 have been shown by the authors. The photoresist´s excellent electroforming behavior has been proved in an extremely acid copper electrolyte at room temperature as well as in an almost neutral nickel electrolyte at 50°C. The easy removal (wet: dimethyl sulfoxide or acetone, dry: plasma with reactive radicals) releases freestanding metal structures with aspect ratios of 13 : 1 and 16 : 1.

Keywords

LIGA; adhesion; copper; electrolytes; electroplating; elemental semiconductors; nickel; organic compounds; photoresists; silicon; AZ 125 nXT; Cu; Ni; Si; Si substrates; UV LIGA; acetone; acrylic photoresist; adhesion; copper electrolyte; dimethyl sulfoxide; electroforming; high-aspect-ratio; microelectroplating; nickel electrolyte; reactive radicals; size 1400 mum; size 400 mum; size 800 mum; temperature 293 K to 298 K; temperature 50 degC; ultrathick UV photoresist; Copper; Fabrication; Microstructure; Resists; Silicon; Substrates; Microelectroplating; UV LIGA; negative photoresists SU-8 versus AZ 125 nXT; wet removal;

fLanguage

English

Journal_Title

Microelectromechanical Systems, Journal of

Publisher

ieee

ISSN

1057-7157

Type

jour

DOI

10.1109/JMEMS.2011.2159098

Filename

5948317