This paper reports some results for an on-going program in wafer-level MEMS package Institute of Microsystems at Huazhong University of Science and Technology. The final goal was to come up with a method usable for various types of MEMS devices in wafer level so that the low cost and high reliability can be achieved at the same time. In this particular paper, three closed-loop microheaters of 5μm, 7μm and 9μm width were designed. By reactive ion sputtering technique, two classes of samples are presented. The first one was first co-sputtered with Ni/Cr and then sputtered with Au metal as heating with Ni/Cr and then sputtered with Au metal as heating material, the second one was sputtered with Cr, Sn and Au respectively as heating material. The bonding of the former sample based on the Ni/Cr and Au heating material failed. The eutectic bonding experiment of the later sample based on the Cr, Sn and Au heating material by global heating method was completed in annealing oven at temperature of about 400°C for 20 minutes and by local heating method was applyed current of 0.8 A into the microheater. The SEM testing result showed the eutectic bonding of Au-Sn by global heating was successful. More results will be reported during the conference presentation.Copyright © 2003 by ASME

Daming Zhang

Papers

Wafer-Level MEMS Package by Gold-Tin Bonding Method