Structure and manufacturing method of a chip scale package

• US 8,158,508 B2
• Filed: 10/31/2007
• Issued: 04/17/2012
• Est. Priority Date: 03/05/2001
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Megica Corporation (Chipbond Technology Corporation)
• Inventors: Lin, Mou-Shiung, Lei, Ming-Ta, Lin, Chuen-Jye
• Primary Examiner(s): ZARNEKE, DAVID A
• Application Number:
  US11/981,125
• Publication Number:
  US 20080088019A1
• Time in Patent Office: 1,630 Days
• Field of Search: 438/614, 438/611, 438/737, 438/739
• US Class Current: 438/614
• CPC Class Codes: H01L 2224/0401 Bonding areas specifically adapted for bump connectors, e.g. under bump metallisation [UBM]
• CPC Class Codes: H01L 2224/04042 Bonding areas specifically adapted for wire connectors, e.g. wirebond pads
• CPC Class Codes: H01L 2224/05572 the external layer extending out of an opening
• CPC Class Codes: H01L 2224/06136 Covering only the central area of the surface to be connected, i.e. central arrangements
• CPC Class Codes: H01L 2224/13007 Bump connector smaller than the underlying bonding area, e.g. than the under bump metallisation [UBM]
• CPC Class Codes: H01L 2224/13017 being non uniform along the bump connector
• CPC Class Codes: H01L 2224/13023 the whole bump connector protruding from 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 2224/131 with a principal constituent of the material being a metal or a metalloid, e.g. boron [B], silicon [Si], germanium [Ge], arsenic [As], antimony [Sb], tellurium [Te] and polonium [Po], and alloys thereof
• 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 2224/16 of an individual bump connector
• CPC Class Codes: H01L 23/49816 Spherical bumps on the substrate for external connection, e.g. ball grid arrays [BGA]
• CPC Class Codes: H01L 24/06 of a plurality of bonding areas
• CPC Class Codes: H01L 24/12 Structure, shape, material or disposition of the bump connectors prior to the connecting process
• CPC Class Codes: H01L 24/16 of an individual bump connector
• CPC Class Codes: H01L 24/17 of a plurality of bump connectors
• 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 2924/01005 : Boron [B]
• CPC Class Codes: H01L 2924/01006 : Carbon [C]
• CPC Class Codes: H01L 2924/01013 : Aluminum [Al]
• CPC Class Codes: H01L 2924/01014 : Silicon [Si]
• CPC Class Codes: H01L 2924/01015 : Phosphorus [P]
• CPC Class Codes: H01L 2924/01018 : Argon [Ar]
• CPC Class Codes: H01L 2924/01022 : Titanium [Ti]
• CPC Class Codes: H01L 2924/01029 : Copper [Cu]
• CPC Class Codes: H01L 2924/01033 : Arsenic [As]
• CPC Class Codes: H01L 2924/01042 : Molybdenum [Mo]
• CPC Class Codes: H01L 2924/0105 : Tin [Sn]
• CPC Class Codes: H01L 2924/01073 : Tantalum [Ta]
• CPC Class Codes: H01L 2924/01074 : Tungsten [W]
• CPC Class Codes: H01L 2924/01075 : Rhenium [Re]
• 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 2924/014 : Solder alloys
• CPC Class Codes: H01L 2924/04941 : TiN
• CPC Class Codes: H01L 2924/12044 : OLED
• CPC Class Codes: H01L 2924/14 : Integrated circuits
• CPC Class Codes: H01L 2924/15311 : being a ball array, e.g. BGA
• CPC Class Codes: H01L 2924/181 : Encapsulation
• CPC Class Codes: H01L 2924/30105 : Capacitance
• CPC Class Codes: H01L 2924/351 : Thermal stress

Abstract

A new method and package is provided for the mounting of semiconductor devices that have been provided with small-pitch Input/Output interconnect bumps. Fine pitch solder bumps, consisting of pillar metal and a solder bump, are applied directly to the I/O pads of the semiconductor device, the device is then flip-chip bonded to a substrate. Dummy bumps may be provided for cases where the I/O pads of the device are arranged such that additional mechanical support for the device is required.

Claims

1. A chip package comprising:

a substrate comprising a solder mask, a first contact point in a channel in said solder mask, a second contact point in said channel, wherein said first contact point is separate from said second contact point in said channel, wherein said channel has a first sidewall and a second sidewall opposite to and substantially parallel with said first sidewall, and an interconnect covered by said solder mask;

a semiconductor device comprising a polymer layer at a top of said semiconductor device and a metal pad having a third contact point at a bottom of an opening in said polymer layer;

a copper pillar between said third contact point and said substrate, wherein said copper pillar is connected to said third contact point through said opening, wherein said copper pillar has a thickness between 10 and 100 micrometers;

a solder between said copper pillar and said substrate, wherein said solder is connected to said copper pillar, wherein said solder electrically contacts said first contact point; and

an underfill between said semiconductor device and said substrate, wherein said underfill contacts said semiconductor device and said substrate, wherein said copper pillar has a sidewall with a bottom edge not covered by said solder, but covered by said underfill.

2. The chip package of claim 1 further comprising a nickel-containing layer between said copper pillar and said solder, wherein said nickel-containing layer is connected to said copper pillar and said solder.

3. The chip package of claim 2, wherein said nickel-containing layer has a thickness between 1 and 10 micrometers.

4. The chip package of claim 1 further comprising a titanium-containing layer between said copper pillar and said third contact point, wherein said copper pillar is connected to said third contact point through said titanium-containing layer.

5. The chip package of claim 4, wherein said titanium-containing layer comprises a titanium-tungsten alloy.

6. The chip package of claim 1, wherein said copper pillar is further over a top surface of said polymer layer.

7. A chip package comprising:

a substrate comprising a solder mask, a first contact point in a channel in said solder mask, a second contact point in said channel, wherein said first contact point is separate from said second contact point in said channel, wherein said channel has a first sidewall and a second sidewall opposite to and substantially parallel with said first sidewall, and an interconnect covered by said solder mask;

a semiconductor device comprising a polymer layer at a top of said semiconductor device and a metal pad having a third contact point at a bottom of an opening in said polymer layer;

a copper pillar between said third contact point and said substrate and over a top surface of said polymer layer, wherein said copper pillar is connected to said third contact point through said opening, wherein said copper pillar has a thickness between 10 and 100 micrometers;

a titanium-containing layer between said third contact point and said copper pillar, wherein said titanium-containing layer is on said third contact point, on said top surface of said polymer layer and in said opening, wherein said copper pillar is connected to said third contact point through said titanium-containing layer;

a solder between said copper pillar and said substrate, wherein said solder is connected to said copper pillar, wherein said solder electrically contacts said first contact point;

a nickel-containing layer between said copper pillar and said solder, wherein said nickel-containing layer is connected to said copper pillar and said solder; and

an underfill between said semiconductor device and said substrate, wherein said underfill contacts said semiconductor device and said substrate, wherein said copper pillar has a sidewall with a bottom edge not covered by said solder, but covered by said underfill.

8. The chip package of claim 7, wherein said nickel-containing layer has a thickness between 1 and 10 micrometers.

9. The chip package of claim 7, wherein said polymer layer comprises polyimide.

10. The chip package of claim 7, wherein said titanium-containing layer comprises titanium nitride.

11. The chip package of claim 7, wherein said titanium-containing layer comprises a titanium-tungsten alloy.

12. A chip package comprising:

a substrate comprising a solder mask, a first contact point in a channel in said solder mask, a second contact point in said channel, wherein said first contact point is separate from said second contact point in said channel, wherein said channel has a first sidewall and a second sidewall opposite to and substantially parallel with said first sidewall, and an interconnect covered by said solder mask;

a semiconductor device comprising a passivation layer at a top of said semiconductor device and a metal pad having a third contact point at a bottom of an opening in said passivation layer;

a copper pillar between said third contact point and said substrate, wherein said copper pillar is connected to said third contact point through said opening, wherein said copper pillar has a thickness between 10 and 100 micrometers;

a solder between said copper pillar and said substrate, wherein said solder is connected to said copper pillar, wherein said solder electrically contacts said first contact point; and

an underfill between said semiconductor device and said substrate, wherein said underfill contacts said semiconductor device and said substrate, wherein said copper pillar has a sidewall with a bottom edge not covered by said solder, but covered by said underfill.

13. The chip package of claim 12, wherein said passivation layer comprises silicon nitride.

14. The chip package of claim 12 further comprising a nickel-containing layer between said copper pillar and said solder, wherein said nickel-containing layer is connected to said copper pillar and said solder.

15. The chip package of claim 14, wherein said nickel-containing layer has a thickness between 1 and 10 micrometers.

16. The chip package of claim 12 further comprising a titanium-containing layer between said copper pillar and said third contact point, wherein said copper pillar is connected to said third contact point through said titanium-containing layer.

17. The chip package of claim 12, wherein said copper pillar is further over a top surface of said passivation layer.

18. A chip package comprising:

a substrate comprising a solder mask, a first contact point, a second contact point separate from said first contact point, and an interconnect covered by said solder mask, wherein none of said solder mask is between said first and second contact points;

a semiconductor device comprising a polymer layer at a top of said semiconductor device and a metal pad having a third contact point at a bottom of an opening in said polymer layer;

a copper pillar between said third contact point and said substrate, wherein said copper pillar is connected to said third contact point through said opening, wherein said copper pillar has a thickness between 10 and 100 micrometers;

a solder between said copper pillar and said substrate, wherein said solder is connected to said copper pillar, wherein said solder electrically contacts said first contact point; and

an underfill between said semiconductor device and said substrate, wherein said underfill contacts said semiconductor device and said substrate, wherein said copper pillar has a sidewall with a bottom edge not covered by said solder, but covered by said underfill.

19. The chip package of claim 18 further comprising a titanium-containing layer between said copper pillar and said third contact point, wherein said copper pillar is connected to said third contact point through said titanium-containing layer.

20. The chip package of claim 19, wherein said titanium-containing layer comprises a titanium-tungsten alloy.

21. The chip package of claim 18 further comprising a nickel-containing layer between said copper pillar and said solder, wherein said nickel-containing layer is connected to said copper pillar and said solder.

22. The chip package of claim 21, wherein said nickel-containing layer has a thickness between 1 and 10 micrometers.

23. The chip package of claim 18, wherein said copper pillar is further over a top surface of said polymer layer.

24. A chip package comprising:

a semiconductor device comprising multiple first contact pads arranged along a first edge of said semiconductor device and in a peripheral region of said semiconductor device, multiple second contact pads arranged along a second edge of said semiconductor device and in said peripheral region, wherein said first edge is opposite to said second edge, multiple third contact pads arranged along a third edge of said semiconductor device and in said peripheral region, and multiple fourth contact pads arranged along a fourth edge of said semiconductor device and in said peripheral region, wherein said third edge is opposite to said fourth edge;

a solder mask over said semiconductor device, wherein no solder mask is between any neighboring two of said multiple first contact pads from a top perspective view;

a circuit substrate over said semiconductor device;

multiple metal bumps between said circuit substrate and said multiple first, second, third and fourth contact pads, wherein one of said multiple metal bumps comprises a copper pillar having a thickness between 10 and 100 micrometers, and a solder between said copper pillar and said circuit substrate, wherein said solder joins said circuit substrate and is connected to said copper pillar; and

an underfill between said semiconductor device and said circuit substrate, wherein said underfill contacts said semiconductor device and said circuit substrate, wherein said copper pillar has a sidewall with a bottom edge not covered by said solder, but covered by said underfill.

25. The chip package of claim 24, wherein said one of said multiple metal bumps further comprises a nickel-containing layer between said solder and said copper pillar.

26. The chip package of claim 25, wherein said nickel-containing layer has a thickness between 1 and 10 micrometers.

27. The chip package of claim 24, wherein said one of said multiple metal bumps further comprises a titanium-containing layer between said copper pillar and one of said multiple first, second, third and fourth contact pads.

28. The chip package of claim 24, wherein said one of said multiple metal bumps further comprises a titanium-nitride layer between said copper pillar and one of said multiple first, second, third and fourth contact pads.

29. The chip package of claim 24, wherein said underfill has no portion vertically under said semiconductor device.

30. The chip package of claim 24 further comprising multiple contact balls on a top surface of said circuit substrate.

31. The chip package of claim 24, wherein said semiconductor device further comprises a polymer layer at a top of said semiconductor device, wherein said one of said multiple metal bumps is further on a top surface of said polymer layer.

32. The chip package of claim 24, wherein said semiconductor device further comprises a passivation layer at a top of said semiconductor device, wherein said passivation layer comprises a nitride, wherein said one of said multiple metal bumps is further on a top surface of said passivation layer.

33. The chip package of claim 32, wherein said nitride comprises silicon nitride.

34. The chip package of claim 24, wherein no solder mask is between any neighboring two of said multiple second contact pads from said top perspective view.

35. The chip package of claim 24, wherein no solder mask is between any neighboring two of said multiple third contact pads from said top perspective view.

36. The chip package of claim 24, wherein no solder mask is between any continuous four of said multiple first contact pads from said top perspective view.