Electrical interconnect in MEMS/NEMS devices by Au/a-Si eutectic reaction

The quality and the reliability of the electrical interconnection have a direct impact on the performance of the MEMS/NEMS devices. In this work, reliable electric interconnection for MEMS/NEMS devices was realized by Au/a-Si (amorphous Si) eutectic reaction in the anodic wafer bonding process. In order to evaluate the qualities of the anodic bonded contact, the electrical property of the Au/a-Si contact was characterized by a modified vertical Kelvin method. The resistor network model of the anodic bonded modified Kelvin structure indicates that the relationship between the contact resistance and the measured resistance can be easily established. The contact resistance was precisely measured by minimizing the interferences from parasitic resistances. The test results indicated that the anodic bonded Au/a-Si contact is Ohmic contact and the qualities of small-size bonded contact is greatly improved compared to that of traditional Au/Si contact. In addition, the fabrication process was also simplified by eliminating the high temperature annealing process after ion implantation.