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US5716532A Expired / Lapsed US ⏱️ 0.0 years remaining

Demetallization of polymer/metal multilayer films by etching

Assignee: Medtronic Inc
•
Filing: 1996-06-11
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Granted: 1998-02-10
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Expires: 2016-06-11
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Abstract

Abstract A method of improving the breakdown strength of polymer multi-layer (PML) capacitors is provided. The method comprises removing metal, specifically, aluminum, from the cut edge. This is done by either etching back the metal electrode layers in either basic or acidic solution or by anodizing the metal to cover that portion of the metal at the edge with an oxide. Removing the metal from the cut edge increases the breakdown strength of the PML capacitors by a factor of two or more.

Inventors

  • 👤 Angelo Yializis
  • 👤 John G. Keimel
  • 👤 Alvin S. Rhorer
  • 👤 Trey W. Huntoon

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 00:36
CPC Classifications
H; H01; H01G; H01G4/00; H01G4/002; H01G4/005; H01G4/012; H01G13/00; H01G13/06; H01G4/30

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 166 words
A method of improving the breakdown strength of polymer multi-layer capacitors comprising a plurality of interleaved metal electrodes forming two plates of each of said capacitors, said metal electrodes separated by a dielectric coating, said method comprising: (a) terminating a first set of metal electrodes on a first face of each of said capacitors; (b) terminating a second set of electrodes on a second face of each of said capacitors, wherein said first and second faces are formed on opposite sides of each of said capacitors; (c) initially forming said capacitors as a stack; (d) slicing said stack into straps along a first direction; (e) slicing said straps into individual said capacitors along a second direction which is orthogonal to said first direction to form said first and second faces; (f) applying termination strips along said first and second faces of said capacitors, to leave exposed metal electrode edges from said slicing along said first direction; and (g) removing metal from said exposed metal electrode edges.
Claim 2
Independent Claim 166 words
A method of improving the breakdown strength of polymer multi-layer capacitors comprising a plurality of interleaved metal electrodes forming two plates of each of said capacitors, said metal electrodes separated by a dielectric coating, said method comprising: (a) terminating a first set of metal electrodes on a first face of each of said capacitors; (b) terminating a second set of electrodes on a second face of each of said capacitors, wherein said first and second faces are formed on opposite sides of each of said capacitors; (c) initially forming said capacitors as a stack; (d) slicing said stack into straps along a first direction; (e) slicing said straps into individual said capacitors along a second direction which is orthogonal to said first direction to form said first and second faces; (f) applying termination strips along said first and second faces of said capacitors, to leave exposed metal electrode edges from said slicing along said first direction; and (g) removing metal from said exposed metal electrode edges.
Claim 3
Dependent Claim 15 words
The method of claim 1 wherein said dielectric coating comprises a cross-linked, radiation-curable acrylic monomer.
Claim 4
Dependent Claim 10 words
The method of claim 2 wherein said metal comprises aluminum.
Claim 5
Dependent Claim 20 words
The method of claim 3 wherein said aluminum has a thickness within a range of about 50 to 500 Å.
Claim 6
Dependent Claim 20 words
The method of claim 3 wherein said aluminum is etched back into said first and second faces about 100 μm.
Claim 7
Dependent Claim 20 words
The method of claim 3 wherein said removal of aluminum is accomplished by etching said aluminum back from said edge.
Claim 8
Dependent Claim 18 words
The method of claim 6 wherein said etching is performed in a liquid etchant having a basic pH.
Claim 9
Dependent Claim 19 words
The method of claim 7 wherein said liquid etchant is selected from the group consisting of KOH and NaOH.
Claim 10
Dependent Claim 25 words
The method of claim 7 wherein said etching is performed for a period of time within the range of about 1 minute to 24 hours.
Claim 11
Dependent Claim 18 words
The method of claim 6 wherein said etching is performed in a liquid etchant having an acidic pH.
Claim 12
Dependent Claim 28 words
The method of claim 10 wherein said liquid etchant is selected from the group consisting of HF, H 3 SO 4 , and phosphoric acid and combinations thereof.
Claim 13
Dependent Claim 25 words
The method of claim 10 wherein said etching is performed for a period of time within the range of about 1 minute to 24 hours.

References Cited (Backward Citations)

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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2001-02-09 2001-08-11 2002-02-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2005-02-09 2005-08-11 2006-02-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2009-02-09 2009-08-11 2010-02-10 $7700.00 Window Closed / Lapsed

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