Wafer-level glass capping as drop-in for miniaturized, advanced optical COB packaging

The novel wafer-level packaging (WLP) process described in this paper allows quasi-hermetic capping of optical devices on wafer-level yielding miniaturized glass cavity windows on top of the optical area, at the same time leaving the contact area accessible for standard electrical connections i.e. wire bond. These smaller chip-size optical cavity packages are used within standard chip-on-board (COB) assemblies for high performance optical applications providing high yield and utmost reliability. In this paper the process flow of generating optical cavity glass wafers as well as of the wafer-level capping process is demonstrated and reliability data on wafer-level and package-level are discussed.