Batch transfer of LIGA microstructures by selective electroplating and bonding

Author

Pan, Li-Wei ; Lin, Liwei

Author_Institution

Dept. of Mech. Eng. & Appl. Mech., Michigan Univ., Ann Arbor, MI, USA

Volume

10

Issue

1

fYear

2001

fDate

3/1/2001 12:00:00 AM

Firstpage

25

Lastpage

32

Abstract

A flip-chip batch transfer process for LIthographie, Galvanoformung and Abformung (LIGA) microstructures has been demonstrated by selective electroplating and bonding. Single layer LIGA microstructures with thickness of 200 μm are fabricated on a dummy substrate first. They are then batch transferred to an IC substrate by means of bonding via electroplating. After the selective bonding process, the originally fixed microstructures become free-standing, moveable devices. The electroplating and bonding process is conducted at 50°C with applied electroplating current density at 68.3 AM² and it takes about 80 minutes to complete the bonding process. Experimentally, an electrothermally-driven LIGA microgripper has been demonstrated to operate after the batch transfer process. When a maximum input current of 1.6 amp is applied, the tip of the microgripper moves 92 μm. This flip-chip assembly process enables a new class of integrated electro-mechanical manufacturing at a low processing temperature massively and in parallel

Keywords

LIGA; current density; electroplating; flip-chip devices; micromanipulators; wafer bonding; 200 micron; 50 degC; LIGA microstructures; batch transfer; current density; electrothermally-driven LIGA microgripper; flip-chip process; integrated electro-mechanical manufacturing; processing temperature; selective bonding process; selective electroplating; Assembly; Bonding processes; Diffusion bonding; Grippers; Manufacturing processes; Microelectronics; Micromechanical devices; Microstructure; Silicon; Temperature;

fLanguage

English

Journal_Title

Microelectromechanical Systems, Journal of

Publisher

ieee

ISSN

1057-7157

Type

jour

DOI

10.1109/84.911088

Filename

911088