摘要 |
A module (20) can include a first substrate (12) comprised of a first material, at least a second substrate (22) comprised of at least a second material, selectively applied solder (14) of a first composition residing between the first substrate and at least the second substrate, and selectively applied solder (16) of at least a second composition residing between the first substrate and at least the second substrate. Preferably, no crack will exist in the module as a result of a reflow process of the solder due to the CTE mismatch between the first and second substrates. The different selectively applied solder compositions can have different melting points and can be solder balls, solder paste, solder preform or any other known form of solder. |