Oxide removal from metallic contact bumps formed on semiconductor devices to improve hybridization cold-welds

Claim 1

A method of joining two semiconductor devices, each having a plurality of metallic contact bumps on major surfaces thereof, said method comprising the steps of: (a) etching the devices to remove oxide from the bumps; (b) orienting the devices so that the bumps on the respective devices are aligned opposite each other; and (c) cold-welding the devices by applying pressure to the devices to cause the bumps to join together to form a single device, whereby the resulting joint has relatively good tensile properties at lower joining pressures.

Claim 2

A method of joining two semiconductor devices, each having a plurality of metallic contact bumps on major surfaces thereof, said method comprising the steps of: (a) etching the devices to remove oxide from the bumps; (b) orienting the devices so that the bumps on the respective devices are aligned opposite each other; and (c) cold-welding the devices by applying pressure to the devices to cause the bumps to join together to form a single device, whereby the resulting joint has relatively good tensile properties at lower joining pressures.

Claim 3

The method of claim wherein step (a) comprises: (1) etching the devices with an etchant gas to remove oxide from the metallic contact bumps; (2) depositing a protective layer on the contact bumps to prevent subsequent oxidation; (3) removing the protective layer prior to welding the contact bumps.

Claim 7

A method of cold-welding two semiconductor devices, each having a plurality of metallic contact bumps on major surfaces thereof, said method comprising the steps of: (a) etching the devices to remove oxide from the area to be welded; (b) transferring the devices to a mating/aligning fixture; (c) aligning the contact bumps of the two devices in the mating/aligning fixture; (d) applying pressure to the devices to cause the bumps to cold-weld together and form a single welded device; and (e) relieving the pressure on the cold-welded device, and whereby the resulting weld has relatively good tensile properties at lower welding pressures.

Claim 8

A method of cold-welding two semiconductor devices, each having a plurality of metallic contact bumps on major surfaces thereof, said method comprising the steps of: (a) etching the devices to remove oxide from the area to be welded; (b) transferring the devices to a mating/aligning fixture; (c) aligning the contact bumps of the two devices in the mating/aligning fixture; (d) applying pressure to the devices to cause the bumps to cold-weld together and form a single welded device; and (e) relieving the pressure on the cold-welded device, and whereby the resulting weld has relatively good tensile properties at lower welding pressures.

Claim 15

A method of cold-welding two semiconductor devices each having a plurality of indium contact bumps on the major surfaces thereof, said method comprising the steps of: (a) placing the semiconductor devices with indium bumps formed thereon in a first chamber capable of evacuation; (b) evacuating the first chamber to remove oxygen therein; (c) introducing into the first chamber a first reactive etchant gas; (d) etching the indium bumps with the gas to remove oxide that may have formed thereon; (e) evacuating the chamber to remove the first reacting etchant gas; (f) introducing into the chamber a plasma that contains material that will form a protective layer on the indium bumps to prevent subsequent oxidation; (g) depositing said material to form a protective layer on the indium bumps; (h) transferring the devices to a second chamber in a mating/aligning fixture; (i) aligning the indium bumps of the respective devices in the mating/aligning fixture; (j) evacuating the second chamber; (k) introducing a second reactive gas into the chamber that will volatilize the protecting coating on the indium bumps to remove the protective layer; and (l) applying pressure to the devices while in the chamber to cause the indium contact bumps to weld together to form a single hybridized device.

Claim 16

A method of cold-welding two semiconductor devices each having a plurality of indium contact bumps on the major surfaces thereof, said method comprising the steps of: (a) placing the semiconductor devices with indium bumps formed thereon in a first chamber capable of evacuation; (b) evacuating the first chamber to remove oxygen therein; (c) introducing into the first chamber a first reactive etchant gas; (d) etching the indium bumps with the gas to remove oxide that may have formed thereon; (e) evacuating the chamber to remove the first reacting etchant gas; (f) introducing into the chamber a plasma that contains material that will form a protective layer on the indium bumps to prevent subsequent oxidation; (g) depositing said material to form a protective layer on the indium bumps; (h) transferring the devices to a second chamber in a mating/aligning fixture; (i) aligning the indium bumps of the respective devices in the mating/aligning fixture; (j) evacuating the second chamber; (k) introducing a second reactive gas into the chamber that will volatilize the protecting coating on the indium bumps to remove the protective layer; and (l) applying pressure to the devices while in the chamber to cause the indium contact bumps to weld together to form a single hybridized device.

Claim 18

A method of welding two semiconductor devices each having a plurality of indium contact bumps on major surfaces thereof, said method comprising the steps of: (a) rinsing the indium contact bumps on the devices in a solvent to remove organic contaminants; (b) immersing the devices in an etchant solution to remove oxide from the indium contact bumps; (c) transferring the devices to a mating/aligning fixture while the indium bumps are still wet from the etchant; (d) aligning the indium bumps of the respective devices in the mating/aligning fixture while the indium bumps are still wet from the etchant; and (e) applying pressure to the devices to cause them to weld together at their indium contact bumps to form a single hybrid device while the devices are still wet from the etchant.

Claim 19

A method of welding two semiconductor devices each having a plurality of indium contact bumps on major surfaces thereof, said method comprising the steps of: (a) rinsing the indium contact bumps on the devices in a solvent to remove organic contaminants; (b) immersing the devices in an etchant solution to remove oxide from the indium contact bumps; (c) transferring the devices to a mating/aligning fixture while the indium bumps are still wet from the etchant; (d) aligning the indium bumps of the respective devices in the mating/aligning fixture while the indium bumps are still wet from the etchant; and (e) applying pressure to the devices to cause them to weld together at their indium contact bumps to form a single hybrid device while the devices are still wet from the etchant.