Localized Compressive Layer Strength Enhancement in Multilayer Glass-ceramic Substrates With the Use of Screening
Original Publication Date: 1986-Aug-01
Included in the Prior Art Database: 2005-Mar-09
Compressive surface layers are commonly used in ceramics for strengthening. These layers are generated by putting a low thermal expansion ceramic on the surface of a higher expansion bulk material. However, the application of this technique to electronic substrates presents difficulty during any post-sintering operation in which the continuous, stressed surface laye inadvertently chipped or purposefully punctured, cut or ground. The compressive layer strengthening is necessary primarily to reduce the high frequency of ceramic fracture resulting from high stresses generated by brazed pins.