US 2026/0231807 A1 · INTERCONNECT WITH LOW-TEMPERATURE SOLDER CAP

Abstract

A low-temperature solder (LTS) cap on solder bumps on a substrate and/or solder bumps on a die may improve head-and-pillow open defects. In some examples, the LTS cap melts earlier than the substrate-side or die-side solder during a TCB process, creating a capillary bridge of molten LTS between the die-side solder and substrate-side solder. In one such example, the molten LTS capillary bridge connecting the die-side and substrate-side bumps may improve the heat transfer to the substrate-side solder and significantly reduce or eliminate head-and-pillow open defects.

Claims20

Dependent claims

A microelectronic assembly, comprising:

a substrate;
an integrated circuit (IC) die over and bonded with the substrate;
and
a plurality of conductive interconnects between and coupled with the substrate and the IC die, wherein:
a conductive interconnect of the plurality of conductive interconnects comprises a first solder material,
in a cross-section of the conductive interconnect, the conductive interconnect comprises regions of a second solder material in the first solder material, and
the second solder material has a different material composition than the first solder material.

4 more elements

Dependencies are inferred from the claim text.

Interconnect with low-temperature solder cap

Life of this patent

Interconnect with low-temperature solder cap

Life of this patent

Abstract

Claims20