The present invention provides a 3D integrated circuit structure formed by stacking semiconductor structures. The semiconductor structures form a multi-die heterogeneous 3D packaging by direct bonding the bonding pads of re-distribution layers. The same or different dies are used to produce the semiconductor structures through the back-end packaging process, and then hybrid bonding technology is used to stack and interconnect the semiconductor structures. The position of the bonding pad can be redefined by re-distribution layer, thereby overcoming the limitations of chip bonding pad position, chip size and quantity.

A semiconductor device and method of manufacturing are disclosed. The semiconductor device includes an optical die, a laser die, and an interposer. The optical die has photonic integrated circuits (PICs), electronic integrated circuits (EICs), and one or more first coupling waveguides. The laser die has at least one laser diode and one or more second coupling waveguides. The optical die and the laser die are bonded to a first side of the interposer using a metal-to-metal bonding, where at least one of the one or more first coupling waveguides is optically aligned with at least one of the one or more second coupling waveguides. An optical glue fills a gap between the aligned at least one of the one or more first coupling waveguides and the at least one of the one or more second coupling waveguides.