Hermetic Solder Sealant System
Original Publication Date: 1979-Oct-01
Included in the Prior Art Database: 2005-Feb-20
This system uses solder to provide a hermetic seal between a ceramic cover and ceramic substrate of an electronic module package. Typical procedure steps are as follows: 1) Clean cover and substrate parts with a 1:1 diluted hydrochloric acid (HCl). (2) Sensitize cleaned parts with a stannous chloride solution acidified with HCl. (3) Activate parts by submersion into a palladium chloride solution acidified with HCl. (4) Submerge parts into electroless copper plating solution, and plate copper film on ceramic areas to be sealed. (5) Submerge parts into electroless gold plating solution, and plate gold film to copper film. (6) Pretin, i.e., presolder, gold film on ceramic covers and substrates. (7) Align individual cover and substrate, and solder together using solder reflow technique.