Ultrathin Glass-Based Wafer-Level Integration for Miniaturized Hermetic MEMS Application

In this article, a glass-based hermetic structure has been packaged at wafer level with a thickness thinner than 200
$\mu \text{m}$
and a size smaller than 1 mm2, showing the prospective way to realize the miniaturization of microelectromechanical systems (MEMS) with high throughput. For the development of this novel wafer-level packaging platform, material selection of metal wire was studied. Next, the technique of metal patterning on the cavity structure was demonstrated for the fabrication of seal ring and electrical connection simultaneously. At last, the ultrathin hermetic structure was sealed by metal-to-metal bonding at wafer level. These technologies can be widely used in advanced miniaturized packaging applications for next-generation electronic components.