Interconnections for flip-chip using lead-free solders and having improved reaction barrier layers

• US 8,314,500 B2
• Filed: 12/28/2006
• Issued: 11/20/2012
• Est. Priority Date: 12/28/2006
• Status: Expired due to Fees

• Current Assignee: Ultratech Incorporated (Veeco Instruments Incorporated)
• Original Assignee: Ultratech Incorporated (Veeco Instruments Incorporated)
• Inventors: Belanger, Luc, Buchwalter, Stephen L., Buchwalter, Leena Paivikki, Giri, Ajay P., Griffith, Jonathan H., Henderson, Donald W., Kang, Sung Kwon, Laine, Eric H., Lavoie, Christian, Lauro, Paul A., Oberson, Valérie Anne, Shih, Da-Yuan, Srivastava, Kamalesh K, Sullivan, Michael J.
• Primary Examiner(s): Pert, Evan
• Assistant Examiner(s): Cruz, Leslie Pilar
• Application Number:
  US11/616,919
• Publication Number:
  US 20080157395A1
• Time in Patent Office: 2,154 Days
• Field of Search: 257/751, 257/753, 257/779, 257/781
• US Class Current: 257/779
• CPC Class Codes: H01L 2224/0401 Bonding areas specifically adapted for bump connectors, e.g. under bump metallisation [UBM]
• CPC Class Codes: H01L 2224/05599 Material
• CPC Class Codes: H01L 2224/114 by blanket deposition of the material of the bump connector
• CPC Class Codes: H01L 2224/11462 Electroplating
• CPC Class Codes: H01L 2224/1147 using a lift-off mask
• CPC Class Codes: H01L 2224/116 by patterning a pre-deposited material treatment of parts prior to assembly of the devices H01L21/48
• CPC Class Codes: H01L 2224/11849 Reflowing
• CPC Class Codes: H01L 2224/119 Methods of manufacturing bump connectors involving a specific sequence of method steps
• CPC Class Codes: H01L 2224/13023 the whole bump connector protruding from the surface
• CPC Class Codes: H01L 2224/13099 Material
• CPC Class Codes: H01L 2224/13111 Tin [Sn] as principal constituent
• 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 24/12 Structure, shape, material or disposition of the bump connectors prior to the connecting process
• 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 2924/01007 Nitrogen [N]
• 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 2924/01023 : Vanadium [V]
• CPC Class Codes: H01L 2924/01024 : Chromium [Cr]
• CPC Class Codes: H01L 2924/01027 : Cobalt [Co]
• CPC Class Codes: H01L 2924/01028 : Nickel [Ni]
• CPC Class Codes: H01L 2924/01029 : Copper [Cu]
• CPC Class Codes: H01L 2924/01033 : Arsenic [As]
• CPC Class Codes: H01L 2924/01037 : Rubidium [Rb]
• CPC Class Codes: H01L 2924/0104 : Zirconium [Zr]
• CPC Class Codes: H01L 2924/01041 : Niobium [Nb]
• CPC Class Codes: H01L 2924/01042 : Molybdenum [Mo]
• CPC Class Codes: H01L 2924/01044 : Ruthenium [Ru]
• CPC Class Codes: H01L 2924/01045 : Rhodium [Rh]
• 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 2924/0105 : Tin [Sn]
• CPC Class Codes: H01L 2924/01051 : Antimony [Sb]
• CPC Class Codes: H01L 2924/01057 : Lanthanum [La]
• CPC Class Codes: H01L 2924/01072 : Hafnium [Hf]
• 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 2924/01077 : Iridium [Ir]
• 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 2924/01083 : Bismuth [Bi]
• CPC Class Codes: H01L 2924/01322 : Eutectic Alloys, i.e. obtained by a liquid transforming into two solid phases
• CPC Class Codes: H01L 2924/01327 : Intermediate phases, i.e. intermetallics compounds
• CPC Class Codes: H01L 2924/014 : Solder alloys
• CPC Class Codes: H01L 2924/04953 : TaN
• CPC Class Codes: H01L 2924/14 : Integrated circuits
• CPC Class Codes: H01L 2924/30107 : Inductance

Abstract

An interconnection structure suitable for flip-chip attachment of microelectronic device chips to packages, comprising a two, three or four layer ball-limiting metallurgy including an adhesion/reaction barrier layer, and having a solder wettable layer reactive with components of a tin-containing lead free solder, so that the solderable layer can be totally consumed during soldering, but a barrier layer remains after being placed in contact with the lead free solder during soldering. One or more lead-free solder balls is selectively situated on the solder wetting layer, the lead-free solder balls comprising tin as a predominant component and one or more alloying components.

Claims

1. In an interconnection structure suitable for flip-chip attachment of microelectronic device chips to chip carriers, a three-layer ball limiting metallurgy consisting of:

an adhesion/diffusion layer deposited on a wafer or substrate, said adhesion/diffusion layer having a upper surface and a lower surface and being formed of a material selected from the group consisting of Ta, and alloys of Cr, Ta and W,

said lower surface being in continuous direct coplanar contact solely with said wafer or said substrate;

a solder reaction barrier layer having a upper surface and a lower surface and being formed of a material selected from the group consisting of Co, Ru, W, V, Rb, Hf, Mo and their alloys; and

an alloy of Ni and one or more elements selected from the group consisting of Co, Mo, W, Ru, Ti, La, Zr, Hf, Cr, Cu, Rb, Ir, Re, Nb, Ta, Au, Pd and Pt, to form a binary, ternary or quaternary alloyed solder reaction barrier layer, and wherein a Ni alloy reaction barrier layer is formed by alloying Ni with W to form a binary nonmagnetic NiW alloy layer, said W composition is greater than 17 weight percent to facilitate sputter-deposition from a nonmagnetic target;

a solder wettable layer formed of a material selected from the group consisting of an alloy of Sn, Pt or Sn;

and optionally consisting of a fourth layer formed of a material selected from the group consisting of Au and Sn;

said upper surface of said adhesion/diffusion layer is in continuous contact with said lower surface of said solder reaction barrier layer.