Particle enhanced joining of metal surfaces

• US 5,334,809 A
• Filed: 02/11/1993
• Issued: 08/02/1994
• Est. Priority Date: 02/14/1990
• Status: Expired due to Term

• Current Assignee: Bio Lab Naturals, Inc. (Limitless X Holdings, Inc.)
• Original Assignee: Particle Interconnect, Inc. (China Crescent Enterprises, Inc.)
• Inventors: DiFrancesco, Louis
• Primary Examiner(s): BARRETT, GLENN
• Application Number:
  US08/016,190
• Time in Patent Office: 537 Days
• Field of Search: 200/514, 200/262, 200/263, 200/264, 200/265, 200/266, 200/267, 200/268, 200/269, 228/180.2, 228/248, 428/645, 428/636, 428/614, 428/609, 428/634, 428/929
• US Class Current: 200/262
• CPC Class Codes: B23K 20/16 with interposition of special material to facilitate connection of the parts, e.g. material for absorbing or producing gas
• CPC Class Codes: B23K 35/02 characterised by mechanical features, e.g. shape
• CPC Class Codes: H01H 1/06 characterised by the shape or structure of the contact-making surface, e.g. grooved
• 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 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 2924/00014 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 2924/01004 Beryllium [Be]
• CPC Class Codes: H01L 2924/01014 Silicon [Si]
• CPC Class Codes: H01L 2924/01078 Platinum [Pt]
• CPC Class Codes: H01L 2924/01079 Gold [Au]
• CPC Class Codes: H01L 2924/01087 Francium [Fr]
• CPC Class Codes: H01L 2924/10253 Silicon [Si]
• CPC Class Codes: H01L 2924/19041 being a capacitor
• CPC Class Codes: H01L 2924/30107 Inductance
• CPC Class Codes: H01L 2924/3011 Impedance
• CPC Class Codes: H05K 3/325 by abutting or pinching, i.e. without alloying process; mechanical auxiliary parts therefor adaptations of leads inserted in holes for press-fit connections H05K3/308
• CPC Class Codes: H05K 3/328 by welding
• CPC Class Codes: H05K 3/4007 Surface contacts, e.g. bumps H05K3/4092 takes precedence; deposition of finish layers on pads H05K3/24; forming solder bumps H05K3/3457
• CPC Class Codes: Y10S 428/929 : Electrical contact feature
• CPC Class Codes: Y10T 29/49117 : Conductor or circuit manufacturing
• CPC Class Codes: Y10T 29/49126 : Assembling bases
• CPC Class Codes: Y10T 428/12486 : Laterally noncoextensive components [e.g., embedded, etc.]
• CPC Class Codes: Y10T 428/24999 : Inorganic

Abstract

A temporary electrical junction includes a first electrical contact having a first metal surface; a second electrical contact having a second metal surface; and a plurality of particulate cores having a hardness greater than that of the first and second metal surfaces, the particulate cores being disposed between the first and second contacts. Force is applied to the first and second contacts such that the particulate cores cause elasto-plastic deformation of at least one of the first and second surfaces, such that the first and second contacts are temporarily joined together at least partly along their respective metal surfaces to complete the electrical junction. An alternate embodiment of the invention provides a temporary structure having a first substrate having a first metal surface; a second substrate having a second metal surface; and a plurality of particulate cores having a hardness greater than that of the first and second metal surfaces disposed between the first and second substrates such that, when force is applied to the first substrate and the second substrate, the particulate cores cause elastoplastic deformation of at least one of the first and second surfaces, such that the first and second substrates are temporarily joined together at least partly along their respective metal surfaces and wherein the first substrate is separable from the second substrate without destruction of the first substrate and the second substrate.

Claims

1. A temporary electrical junction comprising:

a first electrical contact having a first metal surface;

a second electrical contact having a second metal surface; and

a plurality of particulate cores having a hardness greater than that of said first and second metal surfaces, said particulate cores being disposed between said first and second contacts such that, when force is applied to said first contact and said second contact, said particulate cores cause elasto-plastic deformation of at least one of said first and second surfaces, such that said first and second contacts are temporarily joined together at least partly along their respective metal surfaces to complete said electrical junction.

2. An electrical junction as in claim 1, wherein the first and second surfaces are generally planar.

3. An electrical junction as in claim 1, wherein the metal surfaces are composed of a metal selected from the group consisting of aluminum, platinum, titanium, tungsten, chrome, nickel, gold, silicon, iron, copper, cobalt, silver, molybdenum, lead, tin, indium, and alloys thereof.

4. An electrical junction as in claim 3, wherein the first and second contacts are composed of the same metal as their respective metal surfaces.

5. An electrical junction as in claim 1, wherein the particulate cores are composed of a material having a hardness greater than about 5.5 mohs.

6. An electrical junction as in claim 1, wherein the particulate cores are composed of a material having a hardness greater than about 7 mohs.

7. An electrical junction as in claim 1, wherein the particulate cores are composed of a natural mineral material selected from the group consisting of diamond, corundum (sapphire), magnetite, garnet, quartz, quartzite, silica, and tripoli.

8. An electrical junction as in claim 1, wherein the particulate cores are composed of a synthetic material selected from the group consisting of oxides, nitrides, and carbides.

9. An electrical junction as in claim 1, wherein the particulate cores have a mean particle size from about 1 μ

m to 2.5 mm.

10. An electrical junction as in claim 9, wherein the particulate cores have an irregular geometry having sharp edges.

11. An electrical junction as in claim 10, wherein the particulate cores are present on at least one of the first and second surfaces at a density from about 50 particles/mm² to 10,000 particles/mm².

12. The electrical junction of claim 1 wherein said first contact can be separated from said second contact without destroying said first and second contacts.

13. An electrical junction as in claim 1, wherein said particulate cores comprise metallized particles.

14. An electrical junction as in claim 13 wherein said metallized particles include a metal selected from the group including ground silicon, nickel, zinc crystals, iron crystals, and aluminum crystals.

15. A temporary structure comprising:

a first substrate having a first metal surface;

a second substrate having a second metal surface; and

a plurality of particulate cores having a hardness greater than that of the first and second metal surfaces disposed between said first and second substrates such that, when force is applied to said first substrate and said second substrate, said particulate cores cause elasto-plastic deformation of at least one of said first and second surfaces, such that said first and second substrates are temporarily joined together at least partly along their respective metal surfaces and wherein said first substrate is separable from said second substrate without destruction of said first substrate and said second substrate.

16. The structure of claim 15 wherein the substrates are composed of the same metal as their respective surfaces.

17. The structure of claim 15 wherein the particulate cores are composed of a natural mineral material selected from the group consisting of diamond, corundum sapphire), magnetite, garnet, quartz, quartzite, silica, and tripoli.

18. The structure of claim 15 wherein the particulate cores are composed of a synthetic material selected from the group consisting of oxides, nitrides, and carbides.

19. The structure of claim 15 wherein the particulate cores have a mean particle size from about 1 micrometer to 2.5 millimeters.

20. An electrical junction as in claim 15, wherein said particulate cores comprise metallized particles.

21. An electrical junction as in claim 20, wherein said metallized particles include a metal selected from the group including ground silicon, nickel, zinc crystals, iron crystals, and aluminum crystals.