Contact structures and methods for making same

• US 7,082,682 B2
• Filed: 09/10/2004
• Issued: 08/01/2006
• Est. Priority Date: 11/16/1993
• Status: Expired due to Fees

• Current Assignee: FormFactor Incorporated
• Original Assignee: FormFactor Incorporated
• Inventors: Khandros, Igor Y.
• Primary Examiner(s): Arbes, Carl J.
• Application Number:
  US10/938,267
• Publication Number:
  US 20050028363A1
• Time in Patent Office: 690 Days
• Field of Search: 298/43, 298/42, 298/79, 298/25, 298/44, 228/180.5
• US Class Current: 29/842
• CPC Class Codes: B23K 1/0016 Brazing of electronic components
• CPC Class Codes: B23K 2101/40 Semiconductor devices
• CPC Class Codes: C23C 18/161 from plating step, e.g. inkjet
• CPC Class Codes: C25D 7/12 Semiconductors
• CPC Class Codes: C25D 7/123 Semiconductors first coated with a seed layer or a conductive layer
• CPC Class Codes: G01R 1/0466 concerning contact pieces or mechanical details, e.g. hinges or cams; Shielding
• CPC Class Codes: G01R 1/06711 Probe needles; Cantilever beams; "Bump" contacts; Replaceable probe pins
• CPC Class Codes: G01R 1/06761 related to layers
• CPC Class Codes: G01R 1/07307 with individual probe elements, e.g. needles, cantilever beams or bump contacts, fixed in relation to each other, e.g. bed of nails fixture or probe card
• CPC Class Codes: G01R 3/00 Apparatus or processes specially adapted for the manufacture or maintenance of measuring instruments , e.g. of probe tips
• CPC Class Codes: G01R 31/2884 using dedicated test connectors, test elements or test circuits on the IC under test G01R31/2855 takes precedence
• CPC Class Codes: G01R 31/2886 Features relating to contacting the IC under test, e.g. probe heads; chucks G01R31/2865 takes precedence, test connections, e.g. test sockets, or probes per se, G01R1/04 or G01R1/06
• CPC Class Codes: H01L 21/4853 Connection or disconnection of other leads to or from a metallisation, e.g. pins, wires, bumps
• CPC Class Codes: H01L 21/563 Encapsulation of active face of flip-chip device, e.g. underfilling or underencapsulation of flip-chip, encapsulation preform on chip or mounting substrate
• CPC Class Codes: H01L 21/6715 Apparatus for applying a liquid, a resin, an ink or the like H01L21/67126 takes precedence
• CPC Class Codes: H01L 21/76897 Formation of self-aligned vias or contact plugs, i.e. involving a lithographically uncritical step self-aligned silicidation on field effect transistors H01L29/665
• CPC Class Codes: H01L 22/20 Sequence of activities consisting of a plurality of measurements, corrections, marking or sorting steps
• CPC Class Codes: H01L 2224/10126 Bump collar
• CPC Class Codes: H01L 2224/10145 Flow barriers
• CPC Class Codes: H01L 2224/1134 Stud bumping, i.e. using a wire-bonding apparatus
• CPC Class Codes: H01L 2224/13099 : Material
• CPC Class Codes: H01L 2224/13111 : Tin [Sn] as principal constituent
• CPC Class Codes: H01L 2224/29099 : Material
• CPC Class Codes: H01L 2224/32225 : the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/45015 : being circular
• CPC Class Codes: H01L 2224/45109 : Indium (In) as principal constituent
• CPC Class Codes: H01L 2224/45111 : Tin (Sn) as principal constituent
• CPC Class Codes: H01L 2224/45116 : Lead (Pb) as principal constituent
• CPC Class Codes: H01L 2224/45117 : the principal constituent melting at a temperature of greater than or equal to 400°C and less than 950°C
• CPC Class Codes: H01L 2224/4512 : Antimony (Sb) as principal constituent
• CPC Class Codes: H01L 2224/45123 : Magnesium (Mg) as principal constituent
• CPC Class Codes: H01L 2224/45124 : Aluminium (Al) as principal constituent
• CPC Class Codes: H01L 2224/45138 : the principal constituent melting at a temperature of greater than or equal to 950°C and less than 1550°C
• CPC Class Codes: H01L 2224/45139 : Silver (Ag) as principal constituent
• CPC Class Codes: H01L 2224/45144 : Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/45147 : Copper (Cu) as principal constituent
• CPC Class Codes: H01L 2224/45155 : Nickel (Ni) as principal constituent
• CPC Class Codes: H01L 2224/45163 : the principal constituent melting at a temperature of greater than 1550°C
• CPC Class Codes: H01L 2224/45164 : Palladium (Pd) as principal constituent
• CPC Class Codes: H01L 2224/45169 : Platinum (Pt) as principal constituent
• CPC Class Codes: H01L 2224/45173 : Rhodium (Rh) as principal constituent
• CPC Class Codes: H01L 2224/45176 : Ruthenium (Ru) as principal constituent
• CPC Class Codes: H01L 2224/4554 : Coating
• CPC Class Codes: H01L 2224/4556 : Disposition, e.g. coating on a part of the core
• CPC Class Codes: H01L 2224/456 : 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 2224/4809 : Loop shape
• CPC Class Codes: H01L 2224/48091 : Arched
• CPC Class Codes: H01L 2224/4813 : Connecting within a semiconductor or solid-state body, i.e. fly wire, bridge wire
• 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 2224/49109 : outside the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/73203 : Bump and layer connectors
• CPC Class Codes: H01L 2224/73265 : Layer and wire connectors
• CPC Class Codes: H01L 2224/78301 : Capillary
• CPC Class Codes: H01L 2224/81205 : Ultrasonic bonding
• CPC Class Codes: H01L 2224/81801 : Soldering or alloying
• CPC Class Codes: H01L 2224/85043 : using a flame torch, e.g. hydrogen torch
• CPC Class Codes: H01L 2224/85045 : using a corona discharge, e.g. electronic flame off [EFO]
• CPC Class Codes: H01L 2224/85201 : Compression bonding
• CPC Class Codes: H01L 2224/85205 : Ultrasonic bonding
• CPC Class Codes: H01L 23/49811 : Additional leads joined to the metallisation on the insulating substrate, e.g. pins, bumps, wires, flat leads H01L23/49827 takes 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 24/29 : of an individual layer connector
• 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 24/49 : of a plurality of wire connectors
• CPC Class Codes: H01L 24/72 : Detachable connecting means consisting of mechanical auxiliary parts connecting the device, e.g. pressure contacts using springs or clips
• CPC Class Codes: H01L 24/81 : using a bump connector
• CPC Class Codes: H01L 25/0652 : the devices being arranged next and on each other, i.e. mixed assemblies
• CPC Class Codes: H01L 25/16 : the devices being of types provided for in two or more different main groups of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N, e.g. forming hybrid circuits
• 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 2924/00013 : 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 2924/00015 : the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed as prior art
• CPC Class Codes: H01L 2924/01005 : Boron [B]
• CPC Class Codes: H01L 2924/01011 : Sodium [Na]
• CPC Class Codes: H01L 2924/01012 : Magnesium [Mg]
• 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 2924/0102 : Calcium [Ca]
• CPC Class Codes: H01L 2924/01022 : Titanium [Ti]
• 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 2924/0103 : Zinc [Zn]
• CPC Class Codes: H01L 2924/01031 : Gallium [Ga]
• CPC Class Codes: H01L 2924/01033 : Arsenic [As]
• CPC Class Codes: H01L 2924/01039 : Yttrium [Y]
• 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 2924/0106 : Neodymium [Nd]
• 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 2924/0132 : Binary Alloys
• 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 2924/10253 : Silicon [Si]
• CPC Class Codes: H01L 2924/10329 : Gallium arsenide [GaAs]
• CPC Class Codes: H01L 2924/15153 : the die mounting substrate comprising a recess for hosting the device
• CPC Class Codes: H01L 2924/1517 : Multilayer substrate
• CPC Class Codes: H01L 2924/15312 : being a pin array, e.g. PGA
• CPC Class Codes: H01L 2924/1532 : the connection portion being formed on the die mounting surface of the substrate
• CPC Class Codes: H01L 2924/15787 : Ceramics, e.g. crystalline carbides, nitrides or oxides
• CPC Class Codes: H01L 2924/16152 : Cap comprising a cavity for hosting the device, e.g. U-shaped cap
• CPC Class Codes: H01L 2924/16195 : Flat cap [not enclosing an internal cavity]
• CPC Class Codes: H01L 2924/19041 : being a capacitor
• CPC Class Codes: H01L 2924/19043 : being a resistor
• CPC Class Codes: H01L 2924/19107 : off-chip wires
• CPC Class Codes: H01L 2924/2075 : larger or equal to 1 micron less than 10 microns
• CPC Class Codes: H01L 2924/20751 : larger or equal to 10 microns less than 20 microns
• CPC Class Codes: H01L 2924/20752 : larger or equal to 20 microns less than 30 microns
• CPC Class Codes: H01L 2924/20753 : larger or equal to 30 microns less than 40 microns
• CPC Class Codes: H01L 2924/20754 : larger or equal to 40 microns less than 50 microns
• CPC Class Codes: H01L 2924/20755 : larger or equal to 50 microns less than 60 microns
• CPC Class Codes: H01L 2924/20756 : larger or equal to 60 microns less than 70 microns
• CPC Class Codes: H01L 2924/20757 : larger or equal to 70 microns less than 80 microns
• CPC Class Codes: H01L 2924/20758 : larger or equal to 80 microns less than 90 microns
• CPC Class Codes: H01L 2924/20759 : larger or equal to 90 microns less than 100 microns
• CPC Class Codes: H01L 2924/2076 : equal to or larger than 100 microns
• CPC Class Codes: H01L 2924/30107 : Inductance
• CPC Class Codes: H01L 2924/3011 : Impedance
• CPC Class Codes: H01L 2924/3025 : Electromagnetic shielding
• CPC Class Codes: H01L 2924/3512 : Cracking
• CPC Class Codes: H01R 12/52 : connecting to other rigid printed circuits or like structures
• CPC Class Codes: H05K 1/141 : One or more single auxiliary printed circuits mounted on a main printed circuit, e.g. modules, adapters H05K1/142 and H05K1/147 take precedence
• CPC Class Codes: H05K 2201/0397 : Tab forming integral conductive tabs H05K3/4092
• CPC Class Codes: H05K 2201/068 : wherein the coefficient of thermal expansion is important
• CPC Class Codes: H05K 2201/1031 : Surface mounted metallic connector elements
• CPC Class Codes: H05K 2201/10318 : Surface mounted metallic pins
• CPC Class Codes: H05K 2201/10378 : Interposers
• CPC Class Codes: H05K 2201/10719 : Land grid array [LGA]
• CPC Class Codes: H05K 2201/10734 : Ball grid array [BGA]; Bump grid array
• CPC Class Codes: H05K 2201/10757 : Bent leads
• CPC Class Codes: H05K 2201/10878 : Means for retention of a lead in a hole
• CPC Class Codes: H05K 2201/10909 : Materials of terminal, e.g. of leads or electrodes of components
• CPC Class Codes: H05K 2201/10946 : Leads attached onto leadless component after manufacturing the component
• CPC Class Codes: H05K 3/308 : Adaptations of leads connectors to printed circuits H01R12/00
• CPC Class Codes: H05K 3/326 : the printed circuit having integral resilient or deformable parts, e.g. tabs or parts of flexible circuits H05K3/365 takes precedence
• CPC Class Codes: H05K 3/3421 : Leaded components
• CPC Class Codes: H05K 3/3426 : characterised by the leads
• CPC Class Codes: H05K 3/368 : parallel to each other H05K3/361 takes precedence
• CPC Class Codes: H05K 3/4015 : using auxiliary conductive elements, e.g. pieces of metal foil, metallic spheres
• CPC Class Codes: H05K 3/4092 : Integral conductive tabs, i.e. conductive parts partly detached from the substrate
• CPC Class Codes: H05K 7/1069 : with spring contact pieces
• CPC Class Codes: Y02P 70/50 : Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y10T 29/49144 : by metal fusion
• CPC Class Codes: Y10T 29/49147 : Assembling terminal to base
• CPC Class Codes: Y10T 29/49149 : by metal fusion bonding
• CPC Class Codes: Y10T 29/49151 : by deforming or shaping
• CPC Class Codes: Y10T 29/49155 : Manufacturing circuit on or in base
• CPC Class Codes: Y10T 29/49174 : Assembling terminal to elongated conductor
• CPC Class Codes: Y10T 29/49179 : by metal fusion bonding
• CPC Class Codes: Y10T 29/49204 : Contact or terminal manufacturing
• CPC Class Codes: Y10T 29/49222 : forming array of contacts or terminals
• CPC Class Codes: Y10T 29/49224 : with coating
• CPC Class Codes: Y10T 29/49609 : Spring making

Abstract

Contact structures are formed by building a core structure on a substrate and over coating the core structure with a material that is harder or has a greater yield strength than the material of the core structure. The core structure may be formed by attaching a wire to the substrate and spooling the wire out from a spool. While spooling the wire out, the spool may be moved to impart a desired shape to the wire. The wire is severed from the spool and over coated. As an alternative, the wire is not over coated. The substrate may be an electronic device, such as a semiconductor die.

Claims

1. A method of forming a contact structure, said method comprising:

building a core structure on a substrate, said core structure defining a desired shape of said contact structure; and

over coating at least a portion of said core structure,

wherein said over coat comprises a material that is one of harder or has a greater yield strength than a material of said core structure.

2. A method claim 1, wherein said building step comprising:

attaching a wire to said substrate;

spooling out said wire; and

severing said wire.

3. The method of claim 2, wherein said spooling step comprises spooling out said wire in said desired shape of said contact structure.

4. The method of claim 3, wherein said spooling step further comprises moving a spool from which said wire is spooled in said desired shape of said contact structure.

5. The method of claim 4, wherein said moving step comprises moving said spool horizontally and vertically with respect to said substrate.

6. The method of claim 3, wherein said desired shape comprises at least one reversal of direction.

7. The method of claim 2, wherein said attaching step comprises bonding an end of said wire to said substrate.

8. The method of claim 2, wherein said substrate comprises a terminal and said attaching step comprises attaching said wire to said terminal.

9. The method of claim 8, wherein:

said substrate comprises a plurality of terminals, and

said method further comprises repeating said attaching, spooling, severing, and over coating steps a plurality of times and thereby forming a plurality of contact structures on said plurality of terminals.

10. The method of claim 1, wherein said material of said over coat is harder than said material of said core structure.

11. The method of claim 1, wherein said material of said over coat has a greater yield strength than said material of said core structure.

12. The method of claim 1, wherein said substrate is a semiconductor device.

13. The method of claim 12, wherein said semiconductor device is a singulated die.

14. The method of claim 13, wherein said die is unpackaged.

15. The method of claim 12, wherein said semiconductor device is a die of an unsingulated semiconductor wafer.

16. The method of claim 1, wherein said building step comprises one of forming, creating, or disposing said core structure on said substrate.

17. A method of forming a contact structure, said method comprising:

attaching a wire to a surface of a substrate;

spooling out said wire from a spool;

while spooling out said wire, moving said spool in a motion that comprises both a vertical movement and a horizontal movement with respect to said surface of said substrate to impart a desired shape of said contact structure to said wire; and

severing said wire.

18. The method of claim 17, wherein said shape comprises at least one reversal of direction.

19. The method of claim 17, wherein said attaching step comprises bonding an end of said wire to said substrate.

20. The method of claim 17, wherein said surface of said substrate comprises a terminal and said attaching step comprises attaching said wire to said terminal.

21. The method of claim 19, wherein:

said surface of said substrate comprises a plurality of terminals, and

said method further comprises repeating said attaching, spooling, moving, and severing steps a plurality of times and thereby forming a plurality of contact structures on said plurality of terminals.

22. The method of claim 19, wherein said substrate is a semiconductor device.

23. The method of claim 21, wherein said semiconductor device is a singulated die.

24. The method of claim 22, wherein said die is unpackaged.

25. The method of claim 21, wherein said semiconductor device is a die of an unsingulated semiconductor wafer.