16455676

Paragraph Number

51

Referring to FIG. 2, an expanded view of the interconnect bumps 14, first RDL 16, and second RDL 18 is illustrated. The two bumps 14 are coupled to two die pads or metal pads 20 on either side of the active area of the device. In various implementations, there may be two or more bumps coupled to two or more die pads. The two bumps 14 are coupled with the first RDL 16 to provide mechanical and electrical connection between die pads 20 on the second side of the semiconductor die and a second RDL 18 that is electrically coupled with outer terminals 22 on the first side 6 of the semiconductor die 4. The use of interconnection bumps and two RDLs eliminates the need to form through silicon vias (TSVs) through the semiconductor die material itself. The formation of TSVs can cause thermal and mechanical stress to the semiconductor die. TSV formation can also cause damage to the die pad including cracks and over etching of the pads. Die pad damage can account for most of the failures in current TSV-type image sensor chip scale packages (CSP). The use of interconnect bumps and multiple RDLs may also enable the use of pad pitches that are smaller than 200 microns. For example, semiconductor packages with interconnect bumps may have pad pitches of about 60 microns. In some implementations, the pad pitch may be about 70 microns where the interconnection bumps are copper pillar bumps. In various implementations, the copper pillar bumps may have solder tips. In other implementations, the interconnect bumps may be solder balls.

Added by DJM 3 2021