Multilayer pillar for reduced stress interconnect and method of making same

• US 10,396,051 B2
• Filed: 01/13/2017
• Issued: 08/27/2019
• Est. Priority Date: 10/11/2007
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Jadhav, Virendra R., Semkow, Krystyna W., Srivastava, Kamalesh K., Sundlof, Brian R.
• Primary Examiner(s): Peterson, Erik T. K.
• Application Number:
  US15/405,431
• Publication Number:
  US 20170133338A1
• Time in Patent Office: 956 Days
• Field of Search: None
• CPC Class Codes: H01L 2224/0401 Bonding areas specifically adapted for bump connectors, e.g. under bump metallisation [UBM]
• CPC Class Codes: H01L 2224/05099 Material
• CPC Class Codes: H01L 2224/05599 Material
• CPC Class Codes: H01L 2224/05666 Titanium [Ti] as principal constituent
• CPC Class Codes: H01L 2224/1145 Physical vapour deposition [PVD], e.g. evaporation, or sputtering
• CPC Class Codes: H01L 2224/11452 Chemical vapour deposition [CVD], e.g. laser CVD
• CPC Class Codes: H01L 2224/11462 Electroplating
• CPC Class Codes: H01L 2224/11901 with repetition of the same manufacturing step
• CPC Class Codes: H01L 2224/13005 Structure
• CPC Class Codes: H01L 2224/13013 being rectangular or square
• 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 2224/13099 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 2224/13124 Aluminium [Al] 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 2224/13166 : Titanium [Ti] as principal constituent
• CPC Class Codes: H01L 2224/13171 : Chromium [Cr] as principal constituent
• CPC Class Codes: H01L 2224/13184 : Tungsten [W] as principal constituent
• CPC Class Codes: H01L 2224/13599 : Material
• CPC Class Codes: H01L 2224/13655 : Nickel [Ni] as principal constituent
• CPC Class Codes: H01L 2224/13666 : Titanium [Ti] as principal constituent
• CPC Class Codes: H01L 2224/13671 : Chromium [Cr] as principal constituent
• CPC Class Codes: H01L 2224/13684 : Tungsten [W] as principal constituent
• CPC Class Codes: H01L 2224/16235 : the bump connector connecting to a via metallisation of the item
• CPC Class Codes: H01L 2224/29099 : Material
• CPC Class Codes: H01L 2224/29599 : Material
• CPC Class Codes: H01L 2224/81815 : Reflow soldering
• CPC Class Codes: H01L 23/562 : Protection against mechanical damage H01L23/02, H01L23/28 take precedence
• 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 24/16 : of an individual bump connector
• CPC Class Codes: H01L 24/81 : using a bump connector
• 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 2924/01022 : Titanium [Ti]
• CPC Class Codes: H01L 2924/01024 : Chromium [Cr]
• CPC Class Codes: H01L 2924/01029 : Copper [Cu]
• 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 2924/01074 : 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 2924/014 : Solder alloys
• CPC Class Codes: H01L 2924/14 : Integrated circuits
• CPC Class Codes: H01L 2924/2064 : larger or equal to 1 micron less than 100 microns
• CPC Class Codes: H01L 2924/351 : Thermal stress
• CPC Class Codes: H01L 2924/35121 : Peeling or delaminating
• CPC Class Codes: H01L 2924/37001 : Yield
• CPC Class Codes: H01L 2924/384 : Bump effects
• CPC Class Codes: Y10T 156/10 : Methods of surface bonding and/or assembly therefor

Abstract

A multi-layer pillar and method of fabricating the same is provided. The multi-layer pillar is used as an interconnect between a chip and substrate. The pillar has at least one low strength, high ductility deformation region configured to absorb force imposed during chip assembly and thermal excursions.

Claims

1. A method, comprising:

providing a chip having a barrier and adhesion layer;

forming a seed layer on the barrier and adhesion layer;

forming a first copper layer on the seed layer;

forming a first intermediate layer on the first copper layer;

forming a second copper layer on first intermediate layer;

forming a second intermediate layer in direct contact with the second copper layer;

forming a third copper layer in direct contact with the second intermediate layer; and

forming a first barrier protective layer at an interface between the first copper layer and the first intermediate layer,

wherein the barrier and adhesion layer is Titanium Tungsten and the first barrier protective layer is nickel.

2. The method of claim 1, further comprising forming a cap layer on the third copper layer.

3. The method of claim 2, wherein the cap layer is solder.

4. The method of claim 1, wherein the first intermediate layer material is a single chemical element selected from a group consisting of:

gold, silver and aluminum.

5. The method of claim 1, further comprising:

forming a second barrier protective layer at an interface between the first intermediate layer and the second copper layer.

6. The method of claim 5, wherein each of the first and second barrier protective layers is nickel.

7. The method of claim 1, wherein the first, second, and third copper layers and the first and second intermediate layers form a pillar that has an overall height which is more than its width.

8. The method of claim 1, wherein:

the forming the first copper layer comprises electroplating the first copper layer on the seed layer; and

the forming the second copper layer comprises using an electroplating bath to form the second copper layer.

9. The method of claim 1, further comprising forming a third barrier protective layer at an interface between the first intermediate layer and the second copper layer.

10. The method of claim 1, further comprising providing no more than three copper layers.

11. The method of claim 10, further comprising providing no more than two intermediate layers.

12. The method of claim 11, wherein the first copper layer includes only copper.

13. A method, comprising:

providing a chip having a barrier and adhesion layer;

forming a seed layer directly on the barrier and adhesion layer;

forming a first copper layer on the seed layer;

forming a first intermediate layer directly on the first copper layer;

forming a second copper layer on first intermediate layer;

forming a second intermediate layer in direct contact with the second copper layer;

forming a third copper layer in direct contact with the second intermediate layer; and

forming a barrier protective layer at an interface between the first intermediate layer and the second copper layer,

wherein the barrier and adhesion layer is Titanium Tungsten and the barrier protective layer is nickel.