Method of forming a multi-chip stacked structure including a thin interposer chip having a face-to-back bonding with another chip

摘要

A temporary substrate having an array of first solder pads is bonded to the front side of a first substrate by reflowing an array of first solder balls. The first substrate is thinned by removing the back side, and an array of second solder pads is formed on the back side surface of the first substrate. The assembly of the first substrate and the temporary substrate is diced to form a plurality of stacks, each including an assembly of a first semiconductor chip and a handle portion. A second semiconductor chip is bonded to an assembly through an array of the second solder balls. The handle portion is removed from each assembly by reflowing the array of the first solder balls, while the array of the second solder balls does not reflow. The assembly is subsequently mounted on a packaging substrate employing the array of the first solder balls.