Method for fabricating circuit component

• US 8,461,679 B2
• Filed: 05/16/2011
• Issued: 06/11/2013
• Est. Priority Date: 01/07/2002
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Megica Corporation (Chipbond Technology Corporation)
• Inventors: Lee, Jin-Yuan, Chou, Chien-Kang, Lin, Shih-Hsiung, Kuo, Hsi-Shan
• Primary Examiner(s): MENZ, LAURA MARY
• Application Number:
  US13/108,743
• Publication Number:
  US 20110215476A1
• Time in Patent Office: 757 Days
• Field of Search: 257/737, 257/462, 257/724
• US Class Current: 257/737
• 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 2224/05611 Tin [Sn] as principal constituent
• CPC Class Codes: H01L 2224/05639 Silver [Ag] as principal constituent
• CPC Class Codes: H01L 2224/05644 Gold [Au] as principal constituent
• CPC Class Codes: H01L 2224/05647 Copper [Cu] as principal constituent
• CPC Class Codes: H01L 2224/05655 Nickel [Ni] as principal constituent
• CPC Class Codes: H01L 2224/05657 Cobalt [Co] as principal constituent
• CPC Class Codes: H01L 2224/05664 Palladium [Pd] as principal constituent
• CPC Class Codes: H01L 2224/05666 Titanium [Ti] as principal constituent
• CPC Class Codes: H01L 2224/05671 Chromium [Cr] as principal constituent
• CPC Class Codes: H01L 2224/05672 Vanadium [V] as principal constituent
• CPC Class Codes: H01L 2224/05684 Tungsten [W] as principal constituent
• CPC Class Codes: H01L 2224/11462 Electroplating
• CPC Class Codes: H01L 2224/1147 using a lift-off mask
• CPC Class Codes: H01L 2224/11474 Multilayer masks
• CPC Class Codes: H01L 2224/11849 Reflowing
• CPC Class Codes: H01L 2224/11906 with modification of the same mask
• CPC Class Codes: H01L 2224/13017 being non uniform along the bump connector
• CPC Class Codes: H01L 2224/13022 : the bump connector being at least partially embedded in the surface
• CPC Class Codes: H01L 2224/1308 : being stacked
• CPC Class Codes: H01L 2224/13083 : Three-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 2224/13155 : Nickel [Ni] as principal constituent
• 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 2224/16237 : the bump connector connecting to a bonding area disposed in a recess of the surface of the item
• CPC Class Codes: H01L 2224/29099 : Material
• CPC Class Codes: H01L 2224/81191 : wherein the bump connectors are disposed only on the semiconductor or solid-state body
• 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 24/03 : Manufacturing methods
• CPC Class Codes: H01L 24/05 : of an individual bonding area
• CPC Class Codes: H01L 24/11 : Manufacturing methods for bumps on insulating substrates H01L21/4853
• CPC Class Codes: H01L 24/13 : of an individual 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 2924/00013 : 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 2924/01012 : Magnesium [Mg]
• CPC Class Codes: H01L 2924/01022 : Titanium [Ti]
• CPC Class Codes: H01L 2924/01023 : Vanadium [V]
• CPC Class Codes: H01L 2924/01024 : Chromium [Cr]
• CPC Class Codes: H01L 2924/01027 : Cobalt [Co]
• 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 2924/01046 : Palladium [Pd]
• CPC Class Codes: H01L 2924/01047 : Silver [Ag]
• CPC Class Codes: H01L 2924/01049 : Indium [In]
• 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 2924/01078 : Platinum [Pt]
• CPC Class Codes: H01L 2924/01079 : Gold [Au]
• CPC Class Codes: H01L 2924/01082 : Lead [Pb]
• CPC Class Codes: H01L 2924/013 : Alloys
• CPC Class Codes: H01L 2924/014 : Solder alloys
• CPC Class Codes: H01L 2924/04953 : TaN
• CPC Class Codes: H01L 2924/10253 : Silicon [Si]
• CPC Class Codes: H01L 2924/14 : Integrated circuits

Abstract

A cylindrical bonding structure and its method of manufacture. The cylindrical bonding structure is formed over the bonding pad of a silicon chip and the chip is flipped over to connect with a substrate board in the process of forming a flip-chip package. The cylindrical bonding structure mainly includes a conductive pillar and a solder cap. The conductive pillar is formed over the bonding pad of the silicon chip and the solder cap is attached to the upper end of the conductive pillar. The solder cap has a melting point lower than the conductive pillar. The solder cap can be configured into a cylindrical, spherical or hemispherical shape. To fabricate the cylindrical bonding structure, a patterned mask layer having a plurality of openings that correspond in position to the bonding pads on the wafer is formed over a silicon wafer. Conductive material is deposited into the openings to form conductive pillars and finally a solder cap is attached to the end of each conductive pillar.

Claims

1. A chip package comprising:

a substrate comprising a first pad having a top surface with a first region, a second region and a third region between said first and second regions, and a solder mask layer on said first and second regions, wherein an opening in said solder mask layer is over said third region;

a chip over said substrate, wherein said chip comprises a second pad vertically over said third region;

a copper pillar between said third region and said second pad, wherein said copper pillar has a width greater than that of said opening;

a nickel-containing layer between said third region and said copper pillar;

a tin-containing layer between said nickel-containing layer and said third region, wherein said tin-containing layer comprises a lower portion in said opening, and an upper portion over said lower portion, over said opening and above a horizontal level of a top surface of said solder mask layer, wherein said top surface of said solder mask layer faces said chip; and

an underfill between said chip and said substrate.

2. The chip package of claim 1, wherein said tin-containing layer comprises silver.

3. The chip package of claim 1, wherein said copper pillar has a thickness greater than a depth of said opening.

4. The chip package of claim 1, wherein said tin-containing layer has a thickness less than that of said copper pillar.

5. The chip package of claim 1, wherein said copper pillar has a sidewall with a portion not covered by said tin-containing layer.

6. The chip package of claim 1, wherein said nickel-containing layer has a thickness less than that of said copper pillar.

7. The chip package of claim 1, wherein said chip further comprises an active device.

8. The chip package of claim 1, wherein said chip further comprises a passivation layer, wherein said copper pillar is connected to said second pad through an opening in said passivation layer.

9. The chip package of claim 1 further comprising a metal layer between said copper pillar and said second pad.

10. The chip package of claim 9, wherein said metal layer comprises titanium.

11. The chip package of claim 9, wherein said metal layer comprises nickel.

12. A chip package comprising:

a substrate comprising a first pad having a top surface with a first region, a second region and a third region between said first and second regions, and a solder mask layer on said first and second regions, wherein an opening in said solder mask layer is over said third region;

a chip over said substrate, wherein said chip comprises a second pad vertically over said third region;

a copper pillar between said third region and said second pad, wherein said copper pillar has a width greater than that of said opening;

a nickel-containing layer between said third region and said copper pillar;

a tin-and-gold-containing layer between said nickel-containing layer and said third region, wherein said tin-containing layer comprises a lower portion in said opening, and an upper portion over said lower portion, over said opening and above a horizontal level of a top surface of said solder mask layer, wherein said top surface of said solder mask layer faces said chip; and

an underfill between said chip and said substrate.

13. The chip package of claim 12, wherein said tin-and-gold-containing layer comprises silver.

14. The chip package of claim 12, wherein said copper pillar has a thickness greater than a depth of said opening.

15. The chip package of claim 12, wherein said tin-containing layer has a thickness less than that of said copper pillar.

16. The chip package of claim 12, wherein said copper pillar has a sidewall with a portion not covered by said tin-and-gold-containing layer.

17. The chip package of claim 12, wherein said nickel-containing layer has a thickness less than that of said copper pillar.

18. The chip package of claim 12, wherein said chip further comprises an active device.

19. The chip package of claim 12, wherein said chip further comprises a passivation layer, wherein said copper pillar is connected to said second pad through an opening in said passivation layer.

20. The chip package of claim 12 further comprising a metal layer between said copper pillar and said second pad.

21. The chip package of claim 20, wherein said metal layer comprises titanium.

22. The chip package of claim 20, wherein said metal layer comprises nickel.