Types of Glass-to-Metal Seals
There are mainly two types of glass to metal seals , one is matched seal and other one is compression seal.
A "matched glass-to-metal seal" uses glass and metal materials with similar coefficients of thermal expansion (CTE), creating a bond through chemical reaction, while a "compression glass-to-metal seal" relies on a large difference in CTE between the glass and metal, where the metal housing shrinks onto the glass during cooling, creating a tight seal through compressive force; essentially, a matched seal bonds the materials together, while a compression seal physically squeezes the glass with the metal to seal it.
Applications
Hermetic Metal Packages are essential in satellite communication systems, avionics, and space electronics where components must withstand extreme temperature cycling and vacuum conditions. They are also used in RF/microwave devices, oscillators, and precision sensors requiring long-term protection against moisture and corrosive environments. Additionally, these packages find application in defense electronics and telecom infrastructure where component failure is not an option.
