Alignment in the packaging of integrated circuits

摘要

A method includes aligning a top package to a bottom package using an alignment mark in the bottom package, and placing the top package over the bottom package, wherein the top package is aligned to the bottom package after the placing the top package over the bottom package. A reflow is then performed to bond the top package to the bottom package.

主权项

1. A method comprising:
forming a bottom package comprising:
bonding a device die onto a package substrate; anddispensing a molding material to mold at least a lower portion of the device die, wherein solder regions on the package substrate have lower parts molded in the molding material, and upper parts protruding out of the molding material, wherein the upper parts protrude out of a planar top surface of the molding material; forming an alignment mark on the bottom package by laser drilling the device die; placing the bottom package in an opening of a reflow boat; aligning a top package to the bottom package using the alignment mark; placing the top package over the bottom package, with the top package aligned to the bottom package after the placing the top package over the bottom package; and performing a reflow to bond the top package to the bottom package that is in the reflow boat.