BONDING TECHNIQUES IN WAFER FABRICATION

摘要

Fabrication of any micro device can hardly be imagined without making use of some type of wafer bonding or cavity sealing. The field of microfabrication is now a major subject, for both scientific research and industrial applications, in the promising field of micro electro mechanical systems. Wafer bonding advantages include: enhanced throughput, improved yield and possibility of testing device at wafer scale prior to dicing. Wafer bonding is of high importance to MEMS device packaging as it provides a cost reduction through Wafer Level Packaging. It was observed that currently MEMS packaging could correspond to up to 70% of total device costs [1]. The present paper is a review article on the various types of bonding techniques widely used in the field of microfabrication, especially the fabrication of MEMS structures. A discussion on the five main bonding techniques – Anodic, Silicon Fusion, Eutectic, Thermocompression, and Adhesive Wafer Bonding is done in this paper. Finally it is concluded on the comparison of these techniques in terms of bonding conditions, applications and other parameters.