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US5156997A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of making semiconductor bonding bumps using metal cluster ion deposition

Assignee: Microelectronics and Computer Technology Corp
•
Filing: 1991-02-11
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Granted: 1992-10-20
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Expires: 2011-02-11
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Abstract

Abstract A method of making bonding bumps on the pads of an electrical chip including depositing a layer of metallic adhesion material over the surface, depositing metallic bumps on the metallic adhesion material over each of the pad areas using a focused liquid metal ion source, and chemically etching the layer of metallic adhesion material off the surface outside of the deposited bumps.

Inventors

  • 👤 Nalin Kumar
  • 👤 Rama R. Goruganthu
  • 👤 Mohammed K. Ghazi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 00:58
CPC Classifications
H; H10; H10W; H10W72/00; H10W72/01; H10W72/019; H10W72/20; H10W72/012; H01; H01J; H01J2201/00; H01J2201/30; H01J2201/304; H01J2201/30446; H01J2201/30453; H01J2201/30457; H05; H05K; H05K2201/00; H05K2201/20; H05K2201/2081; H05K2203/00; H05K2203/05; H05K2203/0548; H05K2203/0554; H05K2203/10; H05K2203/107; H05K3/00; H05K3/0011; H05K3/0017; H05K3/0023; H05K3/0041; H10W72/01215; H10W72/01221; H10W72/01223; H10W72/251; H10W72/252; H10W72/90; H10W72/921; H10W72/923; H10W72/951; H10W72/952

Claims Analysis

Total Claims: 24
Claim 1
Independent Claim 28 words
A method of making electrical connection bumps on pad areas of an electrical substrate, comprising: depositing metallic bumps on the pad areas by localized metal cluster ion deposition.
Claim 2
Independent Claim 28 words
A method of making electrical connection bumps on pad areas of an electrical substrate, comprising: depositing metallic bumps on the pad areas by localized metal cluster ion deposition.
Claim 3
Dependent Claim 25 words
The method of claim 1 wherein the localized metal cluster ion deposition is provided by an ion beam generated from a liquid metal ion source.
Claim 4
Dependent Claim 19 words
The method of claim 2 wherein the metallic bumps are deposited at a focused spot of the ion beam.
Claim 5
Dependent Claim 31 words
The method of claim 2 wherein the pad areas are spaced less than 1 mm from the ion source, thereby allowing the bumps to be deposited from an unfocused ion beam.
Claim 6
Independent Claim 70 words
A method of making electrical connection bumps on pas areas of an electrical substrate, comprising the following steps in the sequence set forth: depositing a layer of a metallic material over the surface of the substrate including the pad areas, depositing metallic bumps over the pad areas by a metal cluster ion beam, and etching the layer of metallic material off the surface of the substrate outside the deposited bumps.
Claim 7
Independent Claim 70 words
A method of making electrical connection bumps on pas areas of an electrical substrate, comprising the following steps in the sequence set forth: depositing a layer of a metallic material over the surface of the substrate including the pad areas, depositing metallic bumps over the pad areas by a metal cluster ion beam, and etching the layer of metallic material off the surface of the substrate outside the deposited bumps.
Claim 8
Independent Claim 72 words
A method of making electrical connection bumps on pad areas of an electrical substrate, comprising the following steps in the sequence set forth: depositing a layer of a metallic material over the surface of the substrate including the pad areas, depositing first metallic bumps over the pad areas by a focused metal cluster ion beam, and etching the layer of metallic material off the surface of the substrate outside the deposited bumps.
Claim 9
Independent Claim 72 words
A method of making electrical connection bumps on pad areas of an electrical substrate, comprising the following steps in the sequence set forth: depositing a layer of a metallic material over the surface of the substrate including the pad areas, depositing first metallic bumps over the pad areas by a focused metal cluster ion beam, and etching the layer of metallic material off the surface of the substrate outside the deposited bumps.
Claim 10
Dependent Claim 18 words
The method of claim 6 wherein the first metallic bumps are deposited with a liquid metal ion source.
Claim 11
Dependent Claim 26 words
The method of claim 6 wherein the first metallic bumps are selected from the group consisting of gold, indium, lead, tin, solder, copper, nickel, and aluminum.
Claim 12
Dependent Claim 17 words
The method of claim 6 wherein the deposited first metallic bumps are thicker than the pad areas.
Claim 13
Dependent Claim 17 words
The method of claim 6 wherein the aspect ratio of the first metallic bumps is approximately one.
Claim 14
Dependent Claim 18 words
The method of claim 6 wherein the deposited first metallic bumps are between 1 and 20 microns thick.
Claim 15
Dependent Claim 17 words
The method of claim 6 including depositing second metallic bumps on each of the first metallic bumps.
Claim 16
Dependent Claim 15 words
The method of claim 12 wherein the second metallic bumps are formed by electroless plating.
Claim 17
Dependent Claim 22 words
The method of claim 12 wherein the second metallic bumps are selected from the group consisting of lead, tin, nickel and gold.
Claim 18
Dependent Claim 22 words
The method of claim 12 wherein the second metallic bumps are formed by dipping the first metallic bumps in a solder dip.
Claim 19
Dependent Claim 15 words
The method of claim 15 wherein the solder dip is a low temperature metallic alloy.
Claim 20
Dependent Claim 23 words
The method of claim 12 wherein the thickness of the second metallic bumps is greater than the thickness of the first metallic bumps.
Claim 21
Independent Claim 92 words
A method of making bonding bumps on the pads of an electrical chip, comprising the following steps in the sequence set forth: depositing a layer of a metallic adhesion material over the surface of the chip including the pads, depositing a metallic bump over each pad using a liquid metal ion source which generates a focused metal cluster ion beam which impinges a focused spot on the metallic adhesion material over each pad, and chemically etching the layer of metallic adhesion material off the surface of the chip outside the deposited bumps.
Claim 22
Independent Claim 92 words
A method of making bonding bumps on the pads of an electrical chip, comprising the following steps in the sequence set forth: depositing a layer of a metallic adhesion material over the surface of the chip including the pads, depositing a metallic bump over each pad using a liquid metal ion source which generates a focused metal cluster ion beam which impinges a focused spot on the metallic adhesion material over each pad, and chemically etching the layer of metallic adhesion material off the surface of the chip outside the deposited bumps.
Claim 23
Dependent Claim 43 words
The method of claim 18 wherein the chip is moved horizontally relative to the focused spot so that the metallic adhesion material over each pad is scanned by the focused spot and the deposited bumps have a larger area than the focused spot.
Claim 24
Dependent Claim 42 words
The method of claim 18, further comprising horizontally oscillating the ion beam by electrical deflection so that the metallic adhesion material over each pad is scanned by the focused spot and the deposited bumps have a larger area than the focused spot.

References Cited (Backward Citations)

JPS5887848A Cited
US4868068A Cited
US4876112A Cited
JPS6376332A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1995-10-20 1996-04-20 1996-10-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1999-10-20 2000-04-20 2000-10-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2003-10-20 2004-04-20 2004-10-20 $7700.00 Window Closed / Lapsed

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