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US4821944A Expired / Lapsed US ⏱️ 0.0 years remaining

Method for bonding a wire and bonding apparatus

Assignee: Mitsubishi Electric Corp
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Filing: 1988-08-09
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Granted: 1989-04-18
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Expires: 2008-08-09
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Abstract

Abstract The method for bonding a wire of this invention comprises the steps of: positioning a metal ball or a wire on a material (to be bonded); applying a pressing force on the metal ball or the wire against the material (to be bonded) and deforming it; inducing eddy currents in the wire to generate heat energy, whereby elements of the wire and the material (to be bonded) are mutually diffused by means of the heat energy and the pressing force, and bonding is completed. The wire bonding apparatus of this invention comprises: a capillary tip having a through-hole which opens onto a end thereof and through which a wire is passed, the capillary tip pressing the wire against a material to be bonded by the end of the tip (flat face); an electromagnetic coil provided around the end of the capillary tip to surround the through-hole; and a power source for supplying a high-frequency current to the electromagnetic coil.

Inventors

  • 👤 Kiyoaki Tsumura

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 13:05
CPC Classifications
B; B23; B23K; B23K20/00; B23K20/002; B23K20/004; B23K20/005; B23K20/007; B23K13/00; B23K13/01; H; H10; H10W; H10W72/00; H10W72/071; H10W72/0711; H10W72/07141; H10W72/075; H10W72/07521; H10W72/07531; H10W72/07532; H10W72/07533; H10W72/07535; H10W72/50; H10W72/531; H10W72/536; H10W72/5363; H10W72/551; H10W72/552; H10W72/5522; H10W72/5524; H10W72/5525; H10W72/59; H10W72/90; H10W72/951; H10W72/952; H10W90/00; H10W90/701; H10W90/751; H10W90/756

Claims Analysis

Total Claims: 30
Claim 1
Independent Claim 96 words
A method for bonding a wire comprising the steps of: a. positioning a metal ball formed at an end of a wire over a material to be bonded; b. pressing said metal ball against said material to be bonded and plastically deforming said ball on said material to be bonded; and c. generating heat energy by inducing an eddy current in a portion of said wire above said deformed metal ball, whereby elements of said metal ball and said material to be bonded are mutually diffused by means of said heat energy and said pressing force.
Claim 2
Independent Claim 96 words
A method for bonding a wire comprising the steps of: a. positioning a metal ball formed at an end of a wire over a material to be bonded; b. pressing said metal ball against said material to be bonded and plastically deforming said ball on said material to be bonded; and c. generating heat energy by inducing an eddy current in a portion of said wire above said deformed metal ball, whereby elements of said metal ball and said material to be bonded are mutually diffused by means of said heat energy and said pressing force.
Claim 3
Dependent Claim 27 words
A method for bonding a wire according to claim 1, wherein said material to be bonded is heated to a temperature of 25° C. to 280° C.
Claim 4
Dependent Claim 18 words
A method for bonding a wire according to claim 1, wherein said wire is mainly composed of copper.
Claim 5
Dependent Claim 18 words
A method for bonding a wire according to claim 1, wherein said wire is mainly composed of gold.
Claim 6
Dependent Claim 18 words
A method for bonding a wire according to claim 1, wherein said wire is mainly composed of aluminum.
Claim 7
Independent Claim 102 words
A method for bonding a wire comprising the steps of: a. positioning a bonding portion of a wire over a material to be bonded; b. pressing said bonding portion of said wire against said material to be bonded and plastically deforming said bonding portion on said material to be bonded; and c. generating heat energy by inducing an eddy current in a portion of said wire above said deformed bonding portion of said wire, whereby elements of said bonding portion of said wire and said material to be bonded are mutually diffused by means of said heat energy and said pressing force.
Claim 8
Independent Claim 102 words
A method for bonding a wire comprising the steps of: a. positioning a bonding portion of a wire over a material to be bonded; b. pressing said bonding portion of said wire against said material to be bonded and plastically deforming said bonding portion on said material to be bonded; and c. generating heat energy by inducing an eddy current in a portion of said wire above said deformed bonding portion of said wire, whereby elements of said bonding portion of said wire and said material to be bonded are mutually diffused by means of said heat energy and said pressing force.
Claim 9
Dependent Claim 27 words
A method for bonding a wire according to claim 6, wherein said material to be bonded is heated to a temperature of 25° C. to 280° C.
Claim 10
Dependent Claim 18 words
A method for bonding a wire according to claim 6, wherein said wire is mainly composed of copper.
Claim 11
Dependent Claim 18 words
A method for bonding a wire according to claim 6, wherein said wire is mainly composed of gold.
Claim 12
Dependent Claim 18 words
A method for bonding a wire according to claim 6, wherein said wire is mainly composed of aluminum.
Claim 13
Dependent Claim 74 words
A wire bonding apparatus comprising: a. a capillary tip having a through-hole which opens onto an end thereof and through which a metal wire is passed for pressing against a material to be bonded to the end of said wire; b. an electromagnetic coil disposed around said capillary tip and surrounding said through-hole at the end portion of said tip; and c. a power source for supplying a high-frequency current to said electromagnetic coil.
Claim 14
Dependent Claim 74 words
A wire bonding apparatus comprising: a. a capillary tip having a through-hole which opens onto an end thereof and through which a metal wire is passed for pressing against a material to be bonded to the end of said wire; b. an electromagnetic coil disposed around said capillary tip and surrounding said through-hole at the end portion of said tip; and c. a power source for supplying a high-frequency current to said electromagnetic coil.
Claim 15
Dependent Claim 15 words
A wire bonding apparatus according to claim 11, wherein said capillary tip is an insulator.
Claim 16
Dependent Claim 13 words
A wire bonding apparatus according to claim 12, wherein said insulator is alumina.
Claim 17
Dependent Claim 13 words
A wire bonding apparatus according to claim 12, wherein said insulator is sapphire.
Claim 18
Dependent Claim 14 words
A wire bonding apparatus according to claim 12, wherein said insulator is alumina zirconia.
Claim 19
Dependent Claim 14 words
A wire bonding apparatus according to claim 12, wherein said insulator is silicon nitride.
Claim 20
Dependent Claim 14 words
A wire bonding apparatus according to claim 12, wherein said insulator is silicon carbide.
Claim 21
Dependent Claim 14 words
A wire bonding apparatus according to claim 11, wherein said electromagnetic coil is copper.
Claim 22
Dependent Claim 14 words
A wire bonding apparatus according to claim 11, wherein said electromagnetic coil is tungsten.
Claim 23
Dependent Claim 36 words
A wire bonding apparatus according to claim 11, wherein said electromagnetic coil has a diameter of 300 μm or less, and said electromagnetic coil has a diameter 1.5 times larger than the diameter of said wire.
Claim 24
Dependent Claim 22 words
A wire bonding apparatus according to claim 11, wherein said electromagnetic coil is wound around the outer periphery of said capillary tip.
Claim 25
Dependent Claim 18 words
A wire bonding apparatus according to claim 11, wherein said electromagnetic coil is buried in said capillary tip.
Claim 26
Dependent Claim 18 words
A wire bonding apparatus according to claim 22, wherein said electromagnetic coil is made by means of printing.
Claim 27
Dependent Claim 18 words
A wire bonding apparatus according to claim 22, wherein said electromagnetic coil is made by means of deposition.
Claim 28
Dependent Claim 18 words
A wire bonding apparatus according to claim 22, wherein said electromagnetic coil is made by means of sputtering.
Claim 29
Dependent Claim 21 words
A wire bonding apparatus according to claim 11, wherein said electromagnetic coil and said through hole have a common central axis.
Claim 30
Dependent Claim 38 words
A wire bonding apparatus according to claim 11, wherein said power source supplies a high-frequency current at a frequency ranging between 60 MHz and 800 MHz and at an output power ranging between 100 mW and 2 W.

References Cited (Backward Citations)

US3497952A Cited
US3891822A Cited
US4315128A Cited
JPS5816540A Cited
US4586642A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-04-17 1992-10-17 1993-04-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-04-17 1996-10-17 1997-04-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-04-17 2000-10-17 2001-04-18 $7700.00 Window Closed / Lapsed

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