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US5607099A Expired / Lapsed US ⏱️ 0.0 years remaining

Solder bump transfer device for flip chip integrated circuit devices

Assignee: FlipChip International LLC
•
Filing: 1995-04-24
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Granted: 1997-03-04
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Expires: 2015-04-24
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Abstract

Abstract A carrier device (10) is provided for transferring solder bumps (16) to a surface of a flip chip integrated circuit device (18). The carrier device (10) is equipped with cavities (12) on its surface for receiving and retaining solder material (14), by which the solder material (14) can be transferred to the flip chip (18) as molten solder bumps (16). The cavities (12) are located on the surface of the carrier device (10) such that the location of the solder material (14) will correspond to the desired solder bump locations on the flip chip (18) when the carrier device (10) is registered with the flip chip (18). The size of the cavities (12) can be controlled in order to deliver a precise quantity of solder material (14) to the flip chip (18).

Inventors

  • 👤 Shing Yeh
  • 👤 William D. Higdon
  • 👤 Ralph E. Cornell

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-06 06:35
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/30; H05K3/32; H05K3/34; H05K3/3465; H05K3/3485; H10; H10P; H10P72/00; H10P72/70; H10P72/74; H05K2203/00; H05K2203/01; H05K2203/0104; H05K2203/0113; H05K2203/03; H05K2203/0338; H05K3/3478; H10W; H10W72/00; H10W72/01; H10W72/012; H10W72/01204; H10W72/20; H10W72/251; H10W72/90; H10W72/921; H10W72/923; H10W72/941; H10W72/944; H10W72/9445; H10W72/951; H10W72/952

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 239 words
A method for transferring solder bumps to solder bump locations on a surface of a flip chip integrated circuit device, the method comprising the steps of: providing a carrier device having cavities located on a surface thereof so as to correspond to the solder bump locations on the flip chip integrated circuit device when the carrier device is registered with the flip chip integrated circuit device, each cavity being defined by walls and a bottom that is substantially parallel with the surface of the carrier device, the walls of each cavity being continuously tapered between the surface of the carrier device and the bottom of the cavity such that the cavity has a greater width at the surface of the carrier device than at the bottom of the cavity; depositing a solder paste in the cavities; melting the solder paste so as to form spherical solder balls, the walls of the cavities causing the solder balls to be centered within the cavities while the solder balls are molten such that the surfaces of the solder balls are spaced apart from the walls; aligning the carrier device with the flip chip integrated circuit device and heating the carrier device so as to liquefy the solder balls in the cavities; and contacting the carrier device with the flip chip integrated circuit device such that the solder balls wet and transfer to solder pads present on the flip chip integrated circuit device.
Claim 2
Independent Claim 239 words
A method for transferring solder bumps to solder bump locations on a surface of a flip chip integrated circuit device, the method comprising the steps of: providing a carrier device having cavities located on a surface thereof so as to correspond to the solder bump locations on the flip chip integrated circuit device when the carrier device is registered with the flip chip integrated circuit device, each cavity being defined by walls and a bottom that is substantially parallel with the surface of the carrier device, the walls of each cavity being continuously tapered between the surface of the carrier device and the bottom of the cavity such that the cavity has a greater width at the surface of the carrier device than at the bottom of the cavity; depositing a solder paste in the cavities; melting the solder paste so as to form spherical solder balls, the walls of the cavities causing the solder balls to be centered within the cavities while the solder balls are molten such that the surfaces of the solder balls are spaced apart from the walls; aligning the carrier device with the flip chip integrated circuit device and heating the carrier device so as to liquefy the solder balls in the cavities; and contacting the carrier device with the flip chip integrated circuit device such that the solder balls wet and transfer to solder pads present on the flip chip integrated circuit device.
Claim 3
Dependent Claim 39 words
A method as recited in claim 1 wherein the cavities are aligned on the surface of the carrier device so as to form solder bumps at the perimeter of the flip chip integrated circuit device during the contacting step.
Claim 4
Dependent Claim 15 words
A method as recited in claim 1 wherein the carrier device comprises a silicon wafer.
Claim 5
Dependent Claim 19 words
A method as recited in claim 3 wherein the surface is a (100) crystallographic plane of the silicon wafer.
Claim 6
Dependent Claim 19 words
A method as recited in claim 1 wherein the depositing step comprises printing the solder paste in the cavities.
Claim 7
Dependent Claim 19 words
A method as recited in claim 1 wherein the carrier device comprises a die separated from a silicon wafer.

References Cited (Backward Citations)

US4733823A Cited
JPH026030A Cited
US5118584A Cited
US5220200A Cited
JPH04263433A Cited
US5219117A Cited
US5261593A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2000-03-03 2000-09-02 2001-03-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2004-03-03 2004-09-02 2005-03-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2008-03-03 2008-09-02 2009-03-04 $7700.00 Window Closed / Lapsed

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