Method of joining chips utilizing copper pillar

• US 8,021,921 B2
• Filed: 05/29/2008
• Issued: 09/20/2011
• Est. Priority Date: 10/25/2002
• Status: Expired due to Fees

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Megica Corporation (Chipbond Technology Corporation)
• Inventors: Lin, Mou-Shiung, Lin, Shih-Hsiung
• Primary Examiner(s): Chambliss; Alonzo
• Application Number:
  US12/128,644
• Publication Number:
  US 20080227237A1
• Time in Patent Office: 1,209 Days
• Field of Search: None
• US Class Current: 438/108
• CPC Class Codes: H01L 2224/023 Redistribution layers [RDL] for bonding areas
• CPC Class Codes: H01L 2224/0401 Bonding areas specifically adapted for bump connectors, e.g. under bump metallisation [UBM]
• CPC Class Codes: H01L 2224/05552 in top view
• CPC Class Codes: H01L 2224/05572 the external layer extending out of an opening
• CPC Class Codes: H01L 2224/05599 Material
• CPC Class Codes: H01L 2224/11462 Electroplating
• CPC Class Codes: H01L 2224/1147 using a lift-off mask
• CPC Class Codes: H01L 2224/11822 by dipping, e.g. in a solder bath
• CPC Class Codes: H01L 2224/1308 being stacked
• CPC Class Codes: H01L 2224/13082 Two-layer arrangements
• CPC Class Codes: H01L 2224/13099 Material
• CPC Class Codes: H01L 2224/13109 Indium [In] as principal constituent
• CPC Class Codes: H01L 2224/13111 Tin [Sn] as principal constituent
• CPC Class Codes: H01L 2224/13113 Bismuth [Bi] as principal constituent
• CPC Class Codes: H01L 2224/13116 Lead [Pb] as principal constituent
• CPC Class Codes: H01L 2224/13118 Zinc [Zn] as principal constituent
• CPC Class Codes: H01L 2224/1312 Antimony [Sb] as principal constituent
• CPC Class Codes: H01L 2224/13123 Magnesium [Mg] as principal constituent
• CPC Class Codes: H01L 2224/13139 Silver [Ag] as principal constituent
• CPC Class Codes: H01L 2224/13144 Gold [Au] as principal constituent
• CPC Class Codes: H01L 2224/13147 : Copper [Cu] as principal constituent
• CPC Class Codes: H01L 2224/1357 : Single coating layer
• CPC Class Codes: H01L 2224/13609 : Indium [In] as principal constituent
• CPC Class Codes: H01L 2224/16145 : the bodies being stacked
• CPC Class Codes: H01L 2224/16225 : the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/29099 : Material
• CPC Class Codes: H01L 2224/32225 : the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/32245 : the item being metallic
• CPC Class Codes: H01L 2224/45099 : Material
• CPC Class Codes: H01L 2224/48091 : Arched
• CPC Class Codes: H01L 2224/48227 : connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48247 : connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48463 : the connecting portion on the bonding area of the semiconductor or solid-state body being a ball bond
• CPC Class Codes: H01L 2224/73204 : the bump connector being embedded into the layer connector
• CPC Class Codes: H01L 2224/73265 : Layer and wire connectors
• CPC Class Codes: H01L 2224/81011 : Chemical cleaning, e.g. etching, flux
• CPC Class Codes: H01L 2224/92247 : the second connecting process involving a wire connector
• CPC Class Codes: H01L 2225/06513 : Bump or bump-like direct electrical connections between devices, e.g. flip-chip connection, solder bumps
• CPC Class Codes: H01L 24/11 : Manufacturing methods for bumps on insulating substrates H01L21/4853
• CPC Class Codes: H01L 24/12 : Structure, shape, material or disposition of the bump connectors prior to the connecting process
• CPC Class Codes: H01L 24/13 : of an individual bump connector
• CPC Class Codes: H01L 24/16 : of an individual bump connector
• CPC Class Codes: H01L 24/48 : of an individual wire connector
• CPC Class Codes: H01L 24/73 : Means for bonding being of different types provided for in two or more of groups H01L24/10, H01L24/18, H01L24/26, H01L24/34, H01L24/42, H01L24/50, H01L24/63, H01L24/71
• CPC Class Codes: H01L 24/81 : using a bump connector
• CPC Class Codes: H01L 25/0657 : Stacked arrangements of devices
• CPC Class Codes: H01L 25/50 : Multistep manufacturing processes of assemblies consisting of devices, each device being of a type provided for in group H01L27/00 or H01L29/00 H01L21/50 takes precedence
• CPC Class Codes: H01L 2924/00 : Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0001 : Technical content checked by a classifier
• CPC Class Codes: H01L 2924/00012 : Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/00013 : Fully indexed content
• CPC Class Codes: H01L 2924/00014 : the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/0002 : Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 2924/01005 : Boron [B]
• CPC Class Codes: H01L 2924/01006 : Carbon [C]
• CPC Class Codes: H01L 2924/01007 : Nitrogen [N]
• CPC Class Codes: H01L 2924/01012 : Magnesium [Mg]
• CPC Class Codes: H01L 2924/01013 : Aluminum [Al]
• CPC Class Codes: H01L 2924/01014 : Silicon [Si]
• CPC Class Codes: H01L 2924/01022 : Titanium [Ti]
• CPC Class Codes: H01L 2924/01024 : Chromium [Cr]
• CPC Class Codes: H01L 2924/01028 : Nickel [Ni]
• CPC Class Codes: H01L 2924/01029 : Copper [Cu]
• CPC Class Codes: H01L 2924/0103 : Zinc [Zn]
• CPC Class Codes: H01L 2924/01033 : Arsenic [As]
• CPC Class Codes: H01L 2924/01047 : Silver [Ag]
• CPC Class Codes: H01L 2924/01049 : Indium [In]
• CPC Class Codes: H01L 2924/0105 : Tin [Sn]
• CPC Class Codes: H01L 2924/01051 : Antimony [Sb]
• CPC Class Codes: H01L 2924/01073 : Tantalum [Ta]
• CPC Class Codes: H01L 2924/01074 : Tungsten [W]
• CPC Class Codes: H01L 2924/01079 : Gold [Au]
• CPC Class Codes: H01L 2924/01082 : Lead [Pb]
• CPC Class Codes: H01L 2924/01083 : Bismuth [Bi]
• CPC Class Codes: H01L 2924/014 : Solder alloys
• CPC Class Codes: H01L 2924/04941 : TiN
• CPC Class Codes: H01L 2924/04953 : TaN
• CPC Class Codes: H01L 2924/09701 : Low temperature co-fired ceramic [LTCC]
• CPC Class Codes: H01L 2924/15151 : the die mounting substrate comprising an aperture, e.g. for underfilling, outgassing, window type wire connections
• CPC Class Codes: H01L 2924/15311 : being a ball array, e.g. BGA
• CPC Class Codes: H01L 2924/15787 : Ceramics, e.g. crystalline carbides, nitrides or oxides
• CPC Class Codes: H01L 2924/15788 : Glasses, e.g. amorphous oxides, nitrides or fluorides
• CPC Class Codes: H01L 2924/181 : Encapsulation

Abstract

A copper pillar may be provided on a chip and a first tin-containing layer may be provided over the copper pillar. A second tin-containing layer may be provided on a substrate. The first tin-containing layer may be joined with the second tin-containing layer during a packaging process.

Claims

1. A method for fabricating a chip package, comprising:

providing a copper pillar on a chip and a first tin-containing layer over said copper pillar, wherein said first tin-containing layer has a thickness less than a thickness of said copper pillar;

providing a second tin-containing layer on a substrate, wherein said second tin-containing layer has a thickness less than said thickness of said copper pillar; and

after said providing said copper pillar on said chip and said first tin-containing layer over said copper pillar and said providing said second tin-containing layer on said substrate, joining said chip with said substrate, wherein said joining said chip with said substrate comprises joining said first tin-containing layer with said second tin-containing layer, wherein said first tin-containing layer contacts said second tin-containing layer, wherein said chip remains joined with said substrate.

2. The method of claim 1 further comprising said providing said copper pillar over a pad in said chip, wherein said copper pillar has a width less than that of said pad.

3. The method of claim 1, wherein said first tin-containing layer comprises silver.

4. The method of claim 1, wherein said providing said second tin-containing layer comprises a screen-printing process.

5. The method of claim 1, wherein said second tin-containing layer comprises silver.

6. The method of claim 1, wherein said joining said first tin-containing layer with said second tin-containing layer comprises a reflow process.

7. A method for fabricating a chip package, comprising:

providing a copper pillar on a chip and a tin-containing layer over said copper pillar, wherein said tin-containing layer has a thickness less than a thickness of said copper pillar;

providing a gold-containing layer on a substrate, wherein said gold-containing layer has a thickness less than said thickness of said copper pillar; and

after said providing said copper pillar on said chip and said tin-containing layer over said copper pillar and said providing said gold-containing layer on said substrate, joining said chip with said substrate, wherein said joining said chip with said substrate comprises joining said tin-containing layer with said gold-containing layer, wherein said tin-containing layer contacts said gold-containing layer, wherein said chip remains joined with said substrate.

8. The method of claim 7 further comprising said providing said copper pillar over a pad in said chip, wherein said copper pillar has a width less than that of said pad.

9. The method of claim 7, wherein said tin-containing layer comprises silver.

10. The method of claim 7, wherein said joining said tin-containing layer with said gold-containing layer comprises a reflow process.

11. A method for fabricating a chip package, comprising:

providing a metal bump on a chip, wherein said metal bump comprises a copper pillar over said chip;

providing a tin-containing layer on a substrate, wherein said tin-containing layer has a thickness greater than 15 micrometers and less than a thickness of said copper pillar; and

joining said chip with said substrate, wherein said joining said chip with said substrate comprises joining said metal bump with said tin-containing layer using a process comprising a reflow process, wherein said metal bump contacts said tin-containing layer, wherein said chip remains joined with said substrate.

12. The method of claim 11, wherein said tin-containing layer comprises silver.

13. The method of claim 11, wherein said tin-containing layer comprises silver and copper.

14. The method of claim 11, wherein said tin-containing layer comprises lead.

15. A method for fabricating a chip package, comprising:

providing a copper pillar on a chip and a first gold-containing layer over said copper pillar, wherein said first gold-containing layer has a thickness less than a thickness of said copper pillar;

providing a second gold-containing layer on a substrate, wherein said second gold-containing layer has a thickness less than said thickness of said copper pillar; and

after said providing said copper pillar on said chip and said first gold-containing layer over said copper pillar and said providing said second gold-containing layer on said substrate, joining said chip with said substrate, wherein said joining said chip with said substrate comprises joining said first gold-containing layer with said second gold-containing layer, wherein said first gold-containing layer contacts said second gold-containing layer, wherein said chip remains joined with said substrate.

16. The method of claim 15 further comprising said providing said copper pillar over a pad in said chip, wherein said copper pillar has a width less than that of said pad.

17. A method for fabricating a multi-chip structure, comprising:

providing a copper layer on a first chip and a first tin-containing layer over said copper layer;

providing a second tin-containing layer on a second chip; and

after said providing said copper layer on said first chip and said first tin-containing layer over said copper layer and said providing said second tin-containing layer on said second chip, joining said first chip with said second chip, wherein said joining said first chip with said second chip comprises joining said first tin-containing layer with said second tin-containing layer, wherein said first tin-containing layer contacts said second tin-containing layer, wherein said first chip remains joined with said second chip.

18. The method of claim 17, wherein said first tin-containing layer comprises silver.

19. The method of claim 17, wherein said first tin-containing layer comprises indium.

20. The method of claim 17, wherein said second tin-containing layer comprises silver.