Corrosion-resistant copper bond pad and integrated device

• US 7,078,796 B2
• Filed: 07/01/2003
• Issued: 07/18/2006
• Est. Priority Date: 07/01/2003
• Status: Expired due to Fees

• Current Assignee: North Star Innovations Inc. (Wi-LAN Inc.)
• Original Assignee: Freescale Semiconductor, Inc. (NXP Semiconductors NV)
• Inventors: Fay, Owen R., Dean, Timothy B., Blake, Terance, Chelini, Remy J., Lytle, William H., Strumberger, George A., Dunn, Gregory J.
• Primary Examiner(s): Owens, Douglas W
• Application Number:
  US10/610,745
• Publication Number:
  US 20050001324A1
• Time in Patent Office: 1,113 Days
• Field of Search: 257/690, 257/736, 257/750, 257/781, 257/762, 257/748, 438/612, 438/678, 438/687, 438/614
• US Class Current: 257/690
• CPC Class Codes: G01L 19/0069 from the sensor to its support
• CPC Class Codes: G01L 19/147 Details about the mounting of the sensor to support or covering means
• 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 2224/05147 Copper [Cu] as principal constituent
• CPC Class Codes: H01L 2224/05155 Nickel [Ni] as principal constituent
• CPC Class Codes: H01L 2224/05164 Palladium [Pd] as principal constituent
• CPC Class Codes: H01L 2224/05644 Gold [Au] as principal constituent
• CPC Class Codes: H01L 2224/13099 Material
• CPC Class Codes: H01L 2224/13109 Indium [In] as principal constituent
• CPC Class Codes: H01L 2224/32225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/45124 Aluminium (Al) as principal constituent
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• 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 2224/48465 the other connecting portion not on the bonding area being a wedge bond, i.e. ball-to-wedge, regular stitch
• CPC Class Codes: H01L 2224/48644 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/48699 Principal constituent of the connecting portion of the wire connector being Aluminium (Al)
• CPC Class Codes: H01L 2224/48744 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 2224/85013 : Plasma cleaning
• CPC Class Codes: H01L 23/498 : Leads, i.e. metallisations or lead-frames on insulating substrates, e.g. chip carriers shape of the substrate H01L23/13
• 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 24/45 : of an individual wire connector
• CPC Class Codes: H01L 24/48 : of an individual wire connector
• 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 2924/00012 : Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/00014 : 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 2924/01011 : Sodium [Na]
• 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 2924/01022 : Titanium [Ti]
• 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 2924/01044 : Ruthenium [Ru]
• 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 2924/01073 : 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 2924/01083 : Bismuth [Bi]
• CPC Class Codes: H01L 2924/01327 : Intermediate phases, i.e. intermetallics compounds
• CPC Class Codes: H01L 2924/014 : Solder alloys
• CPC Class Codes: H01L 2924/04941 : TiN
• CPC Class Codes: H01L 2924/04953 : TaN
• CPC Class Codes: H01L 2924/05042 : Si3N4
• CPC Class Codes: H01L 2924/09701 : Low temperature co-fired ceramic [LTCC]
• CPC Class Codes: H01L 2924/10253 : Silicon [Si]
• CPC Class Codes: H01L 2924/14 : Integrated circuits
• CPC Class Codes: H01L 2924/181 : Encapsulation
• CPC Class Codes: H01L 2924/19041 : being a capacitor
• CPC Class Codes: H01L 2924/3025 : Electromagnetic shielding

Abstract

The invention provides an integrated device with corrosion-resistant capped copper bond pads. The capped copper bond pads include at least one copper bond pad on a semiconductor substrate. An activation layer comprising one of immersion palladium, electroless cobalt, or immersion ruthernium is disposed on the copper bond pad. A first intermediate layer of electroless nickel-boron alloy is disposed on the activation layer. A second intermediate layer comprising one of electroless nickel or electroless palladium is disposed on the first intermediate layer, and an immersion gold layer is disposed on the second intermediate layer. A capped copper bond pad and a method of forming the capped copper bond pads are also disclosed.

Claims

1. An integrated device with a corrosion-resistant capped copper bond pad, comprising:

at least one copper bond pad on a semiconductor substrate;

an activation layer comprising one of immersion palladium, electroless cobalt, or immersion ruthenium disposed on the copper bond pad;

a first intermediate layer of electroless nickel-boron alloy disposed on the activation layer;

a second intermediate layer comprising one of electroless nickel or electroless palladium disposed on the first intermediate layer;

an immersion gold layer disposed on the second intermediate layer; and

an electroless gold layer disposed on the immersion gold, wherein the electroless gold layer has a thickness between 0.1 microns and 1.5 microns.

2. The integrated device of claim 1 wherein the integrated device is selected from the group consisting of an integrated circuit, an analog circuit, a digital circuit, a radio-frequency device, a semiconductor sensor, an integrated sensor, a pressure sensor, a microelectromechanical device, a microoptoelectromechanical device, a sensor assembly, an integrated circuit assembly, a wire-bonded assembly, and a combination thereof.

3. The integrated device of claim 1 wherein the semiconductor substrate comprises one of a silicon wafer or a silicon die.

4. The integrated device of claim 1 wherein the first intermediate layer of electroless nickel-boron alloy has a thickness between 0.1 microns and 0.5 microns.

5. The integrated device claim 1 wherein the first intermediate layer of electroless nickel-boron alloy has a boron concentration between 0.1 percent and 5.0 percent by weight.

6. The integrated device of claim 1 wherein the second intermediate layer of electroless nickel has a thickness between 0.5 microns and 7.5 microns.

7. The integrated device of claim 1 wherein the second intermediate layer of electroless nickel comprises boron alloyed with the electroless nickel, the boron having a concentration between 0.1 percent and 5.0 percent by weight.

8. The integrated device of claim 1 wherein the second intermediate layer of electroless nickel comprises phosphorus alloyed with the electroless nickel, the phosphorus having a concentration between 10.0 percent and 25.0 percent by weight.

9. The integrated device of claim 1 wherein the second intermediate layer of electroless palladium has a thickness between 0.25 microns and 3.0 microns.

10. The integrated device of claim 1 wherein the immersion gold layer has a thickness between 0.05 microns and 0.25 microns.

11. A method of forming a corrosion-resistant capped copper bond pad, comprising:

providing a plurality of copper bond pads on a semiconductor substrate;

plating an activation layer with one of immersion palladium, electroless cobalt, or immersion ruthenium on the copper bond pads;

plating a first intermediate layer with electroless nickel-boron alloy on the activation layer;

plating a second intermediate layer with one of electroless nickel or electroless palladium on the first intermediate layer;

plating an immersion gold layer on the second intermediate layer; and

plating an electroless gold layer on the immersion gold, wherein the electroless gold layer has a thickness between 0.1 microns and 1.5 microns.

12. The method of claim 11 wherein the provided semiconductor substrate comprises one of a silicon wafer or a silicon die.

13. The method of claim 11 wherein the first intermediate layer of electroless nickel-boron alloy is plated to a thickness between 0.1 microns and 0.5 microns.

14. The method of claim 11 wherein the first intermediate layer of electroless nickel-boron alloy is plated with a boron concentration between 0.1 percent and 5.0 percent by weight.

15. The method of claim 11 wherein the second intermediate layer of electroless nickel is plated to a thickness between 0.5 microns and 7.5 microns.

16. The method of claim 11 wherein the plated second intermediate layer of electroless nickel comprises boron alloyed with the electroless nickel, the boron having a concentration between 0.1 percent and 5.0 percent by weight.

17. The method of claim 11 wherein the plated second intermediate layer of electroless nickel comprises phosphorus alloyed with the electroless nickel, the phosphorus having a concentration between 10.0 percent and 25.0 percent by weight.

18. The method of claim 11 wherein the second intermediate layer of electroless palladium is plated to a thickness between 0.25 microns and 3.0 microns.

19. The method of claim 11 wherein the immersion gold layer is plated to a thickness between 0.05 microns and 0.25 microns.

20. A semiconductor wafer with a plurality of corrosion-resistant capped copper bond pads, comprising:

a plurality of copper bond pads on a surface of the semiconductor wafer;

an activation layer comprising one of immersion palladium, electroless cobalt, or immersion ruthenium disposed on the copper bond pads;

a first intermediate layer of electroless nickel-boron alloy disposed on the activation layer;

a second intermediate layer comprising one of electroless nickel or electroless palladium disposed on the first intermediate layer;

an immersion gold layer disposed on the second intermediate layer; and

an electroless gold layer disposed on the immersion gold, wherein the electroless gold layer has a thickness between 0.1 microns and 1.5 microns.

21. The semiconductor wafer of claim 20, wherein the semiconductor wafer comprises a silicon substrate.

22. The semiconductor wafer of claim 20, wherein the semiconductor wafer comprises an integrated device selected from the group consisting of an integrated circuit, an analog circuit, a digital circuit, a radio-frequency device, a semiconductor sensor, an integrated sensor, a pressure sensor, a microelectromechanical device, a microoptoelectromechanical device, a wire-bondable device, and a combination thereof.

23. The semiconductor wafer of claim 20 wherein the second intermediate layer of electroless nickel comprises boron alloyed with the electroless nickel, the boron having a concentration between 0.1 percent and 5.0 percent by weight.

24. The semiconductor wafer of claim 20 wherein the second intermediate layer of electroless nickel comprises phosphorus alloyed with the electroless nickel, the phosphorus having a concentration between 10.0 percent and 25.0 percent by weight.

25. A capped copper bond pad for a corrosion-resistant integrated device, comprising:

an activation layer comprising one of immersion palladium, electroless cobalt, or immersion ruthenium disposed on at least one copper bond pad;

a first intermediate layer of electroless nickel-boron alloy disposed on the activation layer;

a second intermediate layer comprising one of electroless nickel or electroless palladium disposed on the first intermediate layer;

an immersion gold layer disposed on the second intermediate layer; and

an electroless gold layer disposed on the immersion gold, wherein the electroless gold layer has a thickness between 0.1 microns and 1.5 microns.

26. The capped copper bond pad of claim 25 wherein the second intermediate layer of electroless nickel comprises boron alloyed with the electroless nickel, the boron having a concentration between 0.1 percent and 5.0 percent by weight.

27. The capped copper bond pad of claim 25 wherein the second intermediate layer of electroless nickel comprises phosphorus alloyed with the electroless nickel, the phosphorus having a concentration between 10.0 percent and 25.0 percent by weight.