The Evolution of Hermetic Infrared Windows and Filters

IR windows and filters are used in packages for a variety of IR detectors, including thermopile, pyroelectric, microbolometer, and narrow-bandgap semiconductors. Windows and filters are optimized to the wavelengths being transmitted, ranging from NIR, SWIR, MWIR to LWIR. The type of package selected will determine the requirements of the IR optic. The IR window or filter can be compatible with hermetic sealing by solder, metal welding, or wafer bonding. Non-hermetic packages can use a simpler optic that simply needs to be compatible with an adhesive. Infrared filters can be discrete or mechanically assembled into an array of numerous filters. Koba reviews the evolution of IR windows and filters from TO-style packages to wafer bonding to filter arrays.

About the presenter
Rich Koba, Ph.D., is a senior product manager at Materion Balzers Optics, located at the Westford, Massachusetts facility where he is responsible for the infrared product lines of Materion. He joined Materion’s electronic materials business unit in 2007 and then transferred to Materion’s optics business unit in 2019. Koba has a bachelor’s degree in ceramic engineering from The Ohio State University and a doctorate in ceramic science from The Pennsylvania State University. He is co-inventor of eight US patents, as well as two patent applications regarding the packaging of optical windows and filters.