Method for manufacturing raised electrical contact patten of controlled geometry

• US 20020023773A1
• Filed: 05/04/2001
• Published: 02/28/2002
• Est. Priority Date: 11/16/1993
• Status: Active Grant

• Current Assignee: FormFactor Incorporated
• Original Assignee: FormFactor Incorporated
• Inventors: Khandros, Igor Yan
• Granted Patent: US 6,538,214 B2
• Time in Patent Office: Days
• US Class Current: 174/250
• 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
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• CPC Class Codes: H01L 2224/45015 : being circular
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• 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
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• 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
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• 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

An interposer includes a substrate having opposing surfaces. Conductive terminals are disposed on both surfaces, and conductive terminals on one surface are electrically connected to conductive terminals on the opposing surface. Elongate, springable, conducive interconnect elements are fixed to conductive terminals on both surfaces.

Claims

1. A method for mounting a protuberant conductive contact to an electronic component, the method comprising sequential steps of:

providing a wire having a continuous feed end,

intimately bonding the feed end to the component,

forming from the bonded feed end a stem which protrudes from the component and has a first stem end thereat,

severing the stem at a second stem end to define a skeleton,

depositing a conductive material to envelope the skeleton and adjacent surface of the component.

2. The method as claimed in claim 1, and immediately before the severing step intimately bonding the second stem end to the component.

4. The method as claimed in claim 1, and immediately after the severing step, continuing sequentially the bonding step and the forming step and the severing step for a predetermined number of stems to comprise the skeleton.

5. The method as claimed in claim 4, and immediately before each of the severing steps each of the second stem ends is intimately bonded to the component.

3. A method for mounting a protuberant conductive contact to an electronic component, the method comprising sequential steps of:

providing a wire having a continuous feed end,

intimately bonding the feed end to the component,

forming from the bonded feed end a stem which protrudes from the component and has a first stem end thereat,

severing the stem at a second stem end to define a skeleton,

depositing a conductive material to jacket the skeleton and adjacent surface of the component.

6. A method for mounting a protuberant conductive contact to a conductive terminal on an electronic component, the method comprising sequential steps of:

providing a wire having a continuous feed end,

intimately bonding the feed end to the terminal,

forming from the feed end a stem which protrudes from the terminal and has a first stem end thereat,

severing the stem at a second stem end to define a skeleton,

depositing a conductive material to envelop the skeleton and adjacent surface of the terminal.

7. The method as claimed in claim 6, and immediately before the severing step intimately bonding the second stem end to the terminal.

8. The method as claimed in claim 6, and immediately after the severing step, continuing sequentially the bonding step and the forming step and the severing step for a predetermined number of stems to comprise the skeleton.

9. The method as claimed in claim 8, and immediately before each of the severing steps each of the second stem ends is intimately bonded to the terminal.

30. The method as claimed in claim 6 or 8, performed on a plurality of the terminals and, wherein:

the forming steps result in a plurality of free-standing protuberant stems,

the severing steps are performed on the respective stems all in a common plane.

31. The method as claimed in claim 6 or 8, performed on a plurality of the terminals on at least one electronic component and, wherein:

the terminals are in different planes,

the forming steps result in a plurality of free-standing protuberant stems,

the severing steps are performed on the respective stems all in a common plane.

32. The method as claimed in claim 6 or 8, performed on a plurality of the terminals on at least one electronic component, wherein shapes of the skeleton and mechanical properties of the conductive material are organized collectively to impart resilience to the protuberant conductive contacts, and the severing steps are performed on the stems all in a common plane.

10. A method for mounting a protuberant conductive contact to a conductive terminal on an electronic component, the method comprising sequential steps of:

providing a wire having a continuous feed end,

intimately bonding the feed end to the terminal,

forming from the bonded feed end a stem which protrudes from the terminal and has a first stem end thereat,

severing the stem at a second stem end to define a skeleton,

depositing a conductive material to jacket the skeleton and adjacent surface of the terminal.

11. The method as claimed in claim 10, and immediately before the severing step intimately bonding the second stem end to the terminal.

12. The method as claimed in claim 10, and immediately after the last mentioned severing step continuing sequentially the bonding step and the forming step and the severing step for a predetermined number of stems to comprise the skeleton.

13. The method as claimed in claim 12, and immediately before each of the severing steps each of the second ends is intimately bonded to the terminal.

16. The method as claimed in claim 15, wherein during the eliminating step the second stem ends are severed from the sacrificial member.

18. The method as claimed in claim 17, performed on a plurality of wires on a plurality of the terminals on the electronic component.

19. The method as claimed in claim 17, with the bonding performed by applying at least one of a group consisting of superambient pressure, superambient temperature and ultrasonic energy.

20. The method as claimed in claim 17, wherein the severing is performed by melting the wire.

21. The method as claimed in claim 17, wherein the forming steps and the severing steps are performed by a wirebonding apparatus, and after the severing steps but before the depositing step shaping the skeleton by means of a tool external to the apparatus.

22. The method as claimed in claim 17, wherein the severing of the second ends is performed by mechanical shearing.

23. The method as claimed in claim 17, wherein during the forming step the shape of the stems is determined by means of a software algorithm in a control system of an automated wirebonding apparatus.

25. The method as claimed in claim 24, wherein the conductive material is provided with a multitude of microprotrusions on its surface.

26. The method as claimed in claim 17, with the depositing step including placement of a plurality of layers each differing from one another.

27. The method as claimed in claim 24, wherein the depositing step includes placement of a plurality of layers each differing from one another.

28. The method as claimed in claim 27, wherein at least one of the layers comprising conductive material has a jagged topography in order to reduce contact resistance of the protuberant conductive contact when mated to a matching terminal.

29. The method as claimed in claim 17 or 24, wherein the deposition is performed by means of electrochemical plating in an ionic solution.

33. The method as claimed in claim 17 or 24, wherein the cross-sectional area of the wire is rectangular.

34. The method as claimed in claim 26 or 27, wherein the wire is made of a metal selected from a group consisting of gold, silver, beryllium, copper, aluminum, rhodium, ruthenium, palladium, platinum, cadmium, tin, lead, indium, antimony, phosphorous, boron, nickel, magnesium and alloys thereof, and wherein at least one of the layers of the conductive material is a metal selected from a group consisting of nickel, phosphorous, boron, cobalt, iron, chromium, copper, zinc, tungsten, tin, lead, bismuth, indium, cadmium, antimony, gold, silver, rhodium, palladium, platinum, ruthenium and alloys thereof.

36. The method as claimed in claim 26 or 27, wherein a layer reactive with material of the wire is interposed between the skeleton and the conductive material.

37. The method as claimed in claim 26 or 27, wherein the wire is gold and the reactive layer is tin.

14. A method for mounting a protuberant conductive contact to a conductive terminal on an electronic component, the method comprising sequential steps of:

providing a wire having a continuous feed end,

intimately bonding the feed end to the terminal,

forming from the bonded feed end a stem which protrudes from the terminal and has a first stem end thereat,

intimately bonding a second stem end to the terminal,

sequentially continuing the forming step and the bonding step for a predetermined number of times,

after the last bonding step severing the stem to define a skeleton,

depositing a conductive material to envelop the skeleton and adjacent surface of the terminal.

17. The method as claimed in claim 6, 7, 8, 9, 14 or 15, performed on a plurality of the terminals on the electronic component.

35. The method as claimed in claim 6, 7, 8, or 14, performed on at least one terminal on an electronic component, wherein the wire is made primarily of a metal selected from a group consisting of gold, copper, aluminum, silver, lead, tin, indium and alloys thereof;

the skeleton is coated with a first layer of the conductive material selected from a group consisting of nickel, cobalt, boron, phosphorous, copper, tungsten, titanium, chromium, and alloys thereof;

a top layer of the conductive material is solder selected from a group consisting of lead, tin, indium, bismuth, antimony, gold, silver, cadmium and alloys thereof.

38. An electronic component a first and a second surface in which on at least one of the surfaces is provided a plurality of the terminals having protuberant conductive contacts mounted thereto and made by means of the method as claimed in any of claims 6, 7, 8, 14, 15 or 34.

15. A method for mounting a protuberant conductive contact to a conductive terminal on an electronic component, the method comprising sequential steps of:

providing a wire having a continuous feed end,

intimately bonding the feed end to the terminal,

forming from the bonded feed end a stem which protrudes from the terminal and has a first stem end thereat,

bonding a second stem end to a sacrificial member mounted in spaced relationship from the component,

severing the stem at the second stem end to define a skeleton,

depositing a conductive material to envelop the skeleton and at least adjacent surface of the component,

eliminating the sacrificial member.

24. The method as claimed in claim 6, 7, 8, 9 or 15, performed on a plurality of the terminals, wherein shape of the skeleton and mechanical properties of the conductive material are organized collectively to impart resilience to the protuberant conductive contact.