Patent ID: 9355928
Filing Date: 2016-05-31
CPC Classification: H01L

Claim Text:
1. A method comprising: attaching a semiconductor die on a first side of a bottom package; mounting the bottom package on a printed circuit board; mounting a top package on the bottom package, wherein the top package is smaller than the bottom package, and wherein the semiconductor die is located between the bottom package and the top package; applying a reflow process so that the bottom package and the top package form a package-on-package structure; and applying a single underfill dispensing process to the package-on-package structure to form both a first underfill layer between the bottom package and the printed circuit board, and a second underfill layer between the top package and the bottom package, wherein the single underfill dispensing process is applied to an edge of the bottom package and an underfill dispensing head is vertically aligned with the edge of the bottom package during the single underfill dispensing process, and wherein through an alignment between the underfill dispensing head and the edge of the bottom package, the single underfill dispensing process can be used to form both the first underfill layer and the second underfill layer.