Patent ID: 9613933
Date: 2017-04-04
CPC Classifications: H01L

Claim:
1. An apparatus, comprising: a substrate; a mold compound disposed on the substrate; a semiconductor die embedded within the mold compound and electrically coupled to lands on the substrate; solder balls disposed around the semiconductor die on the substrate, the solder balls each having a respective solid coating thereon, the solid coating containing a cleaning agent to promote the solder balls' respective coalescence with other solder balls, wherein, an active potential of the cleaning agent does not appreciably decay during extended storage of the apparatus between construction of the apparatus and a reflow of the solder balls so that the solder balls will coalesce during the reflow with the other solder balls, the other solder balls being components of a packaged semiconductor die when the apparatus is attached to the packaged semiconductor die to form a package-on-package structure; respective vias formed in the mold compound that expose the solder balls and their respective solid coatings.