Patent ID: 8053277

Claim:
A method comprising: providing a wafer comprising a first die and a second die, each comprising a first bonding pad on a top surface of the corresponding first and second dies; providing a third die and a fourth die each comprising a first surface and a second surface opposite the first surface; stacking the third die on the first die, and the fourth die on the second die, wherein a second bonding pad on the first surface of each of the third and the fourth dies is bonded to the first bonding pad of the first die through flip-chip bonding, and wherein the third die and the fourth die have a gap therebetween; forming a protection layer comprising vertical portions on sidewalls of the third and the fourth dies, and a horizontal portion directly over the first die and the second die; and forming a coating on the protection layer and filling a remaining space of the space between the third and the fourth dies.