A novel low cost wafer level hermetic packaging approach for the implantable devices

Implantable devices have attracted extensive attention with the rapid development of wearable electronics and health monitoring. However, packaging of implantable devices is still challenging for the bio-compatibility, hermeticity, and CMOS-compatibility requirements. In this paper, a wafer-level hermetic packaging method based on Au-Sn alloy eutectic bonding was proposed, which has a low cost and a small packaging size. The packaging process flow was dedicated designed and the bonding morphology, shear strength, cell response, and hermeticity of the proposed method was characterized. Furthermore, the effects of critical parameters such as seal ring width on the packaging properties were investigated. The experiment results indicated that the proposed packaging method has good reliabilities, bio-compatibility and is suitable for the miniaturization trend of the implantable devices.