Pillar connections for semiconductor chips and method of manufacture
AssigneeAdvanpack Solutions Pte Ltd.
InventorFrancisca Tung
Life of this patent
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Abstract
A flip chip interconnect system comprises an elongated pillar comprising two elongated portions, a first portion including solder with or without lead and a second portion including copper or gold or other material having a higher reflow temperature than the first portion. The second portion is to be connected to the semiconductor chip and has a length preferably of more than 55 microns to reduce the effect of α particles from the solder from affecting electronic devices on the chip. The total length of the pillar is preferably in the range of 80 to 120 microns.
Claims9
A method for making electrical connections to a semiconductor chip, comprising:
- forming a layer of photosensitive material over the chip;
- exposing the layer to radiation at predetermined areas and removing portions of the layer that are exposed to radiation to form through holes in the layer, thereby exposing areas of the chip through the holes;
- filling portions of the holes with a metal to form an elongated column of metal material, so that the metal material is in contact with the chip;
- filling portions of the holes with solder to form an elongated column of solder, so that the solder is in contact with the metal material;
- and
- removing the layer.
A method for making electrical connections to a semiconductor chip, comprising:
- forming a plurality of pillars connected to a semiconductor chip, each of said pillars comprising at least two elongated portions, a first portion including a metal material, and a second portion including solder,
- wherein said metal material is different from the material in the second portion,
- wherein said first portion is in contact with the semiconductor chip,
- and wherein said second portion comprises a ball-shaped portion including a solder material, said first portion containing a material with a higher reflow temperature than the material of the ball-shaped portion;
- and
- providing a layer of material on a side surface of the first portion of at least one of the plurality of pillars, by heating the metal material in an environment that contains oxygen, to an elevated temperature, to oxidize the metal material.
Dependencies are inferred from the claim text.