Current Status of Vacuum Brazing Technology for Optical Windows

As a key shell component of semiconductor optoelectronic device packages, optical windows provide an indispensable optical signal transmission channel for optoelectronic devices, and the sealing quality of the structure has a significant impact on the long-term life of the device. Vacuum brazing technology is the process of obtaining a hermetic optical window by welding a metal shell and metalized optical window with solder under a vacuum environment and is one of the main technologies used to seal optical windows. It has the advantages of low sealing temperature, high air-tightness, good flatness, and long-term reliability, and it is widely used in the fields of optical device vacuum hermetic packaging and optical equipment manufacturing. In this study, the research status of vacuum brazing technology for optical windows is introduced from the perspectives of filler metal type, metallization structure design, brazing equipment, welding void ratio, gas tightness, and mechanical properties, and the development trends of future technologies in this field are discussed.