A low-temperature wafer bonding technique using patternable materials

• Published in: Journal of micromechanics and microengineering Vol. 12; no. 5; pp. 611 - 615
• Main Authors: Pan, C-T, Yang, H, Shen, S-C, Chou, M-C, Chou, H-P
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 01.09.2002; Institute of Physics
• Subjects: Applied sciences; Bond strength (materials); Bonding; Electronics; Exact sciences and technology; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Lithography, masks and pattern transfer; Low temperature effects; Mechanical instruments, equipment and techniques; Microelectronic fabrication (materials and surfaces technology); Micromechanical devices and systems; Microstructure; Physics; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Silicon wafers; Wafer bonding; Precision engineering; Plastic packaging; Miniaturization; Experimental study; Microelectromechanical device; Low temperature
• ISSN: 0960-1317; 1361-6439
• DOI: 10.1088/0960-1317/12/5/315

We present a silicon wafer bonding technique for 3D microstructures using MEMS process technology. Photo-definable material with patternable characteristics served as the bonding layer between the silicon wafers. A bonding process was developed and several types of photo-definable material were tested for bonding strength and pattern spatial resolution. The results indicated that SU-8 is the best material with a bonding strength of up to 213 kg/sq cm (20.6 MPa), and a spatial resolution of 10 microns, at a layer thickness of up to 100 microns. The low-temperature bonding technique that is presented is particularly suitable for microstructure and microelectronics integration involved in MEMS packaging. (Author)