Wafer level bonding using localized radio-frequency induction heating

Abstract

A wafer level bonding technique by localized induction heating has been developed and demonstrated in this paper. A suitable fabrication process scheme has also been established for the localized induction heating and bonding. It takes only about 20 seconds to complete the bonding process. The temperatures of solder loops and the central area of solder loops are above 300°C and below 70°C, respectively. Due to the solder reflow, robust and hermetic glass wafer bonding is accomplished, and the average tensile strength is 6.42 MPa. Under-heated or over-heated bonding has been found to result in cracks at bonding interfaces and sputtering layer, which degrades the bonding qualities. wafer bonding, induction heating, MEMS, MEMS packaging Citation:Chen M X, Liu W M, Xi Y Y, et al. Wafer level bonding using localized radio-frequency induction heating.

Properties of Sn‐Ag‐Cu Solder Joints Prepared by Induction Heating

“…e heat is produced directly in the metallic workpiece during induction heating. As such, the nonmetallic parts of the soldered electronics are only minimally heated [19,20]. Li et al calculated and experimentally confirmed that the heat produced in the solder ball depends on its size and higher temperatures could be generated in larger solder balls [21].…”

Batch welding of aligned carbon nanotube onto metal electrodes

“…This technology has been extensively employed to heat electrically conductive materials for bonding applications (Yang et al 2005;Chen et al 2010). In this work, largescale bonding of CNTs onto electrodes with the assistance of radio frequency induction heating is developed and presented.…”