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US4801067A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of connecting metal conductor to ceramic substrate

Assignee: Niterra Co Ltd
•
Filing: 1987-08-27
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Granted: 1989-01-31
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Expires: 2007-08-27
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Abstract

Abstract A method of connecting a metal conductor to a ceramic substrate including the steps of providing a terminal portion on the ceramic substrate, the ceramic substrate having a dielectric constant less than or equal to 7.0 units and a coefficient of thermal expansion of 5×10 -6 /° C. or less, forming at least one of a buffer layer and a barrier layer overlying the terminal portion of the ceramic substrate, wherein the buffer layer consists essentially of Cu and the barrier layer consists essentially of a material selected from the group consisting of Ni, Pd, and Pt, and brazing a metal conductor to the terminal portion of the ceramic substrate through the at least one of the buffer layer and the barrier layer with an Ag-based brazing filler material.

Inventors

  • 👤 Kazuo Kondo
  • 👤 Tsuneyuki Sukegawa
  • 👤 Asao Morikawa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 21:52
CPC Classifications
H; H10; H10P; H10P72/00; H10P72/04; H10P72/0444; B; B23; B23K; B23K35/00; B23K35/001; C; C04; C04B; C04B37/00; C04B37/02; C04B37/023; C04B37/026; H10W; H10W70/00; H10W70/099; C04B2237/00; C04B2237/02; C04B2237/12; C04B2237/123; C04B2237/124; C04B2237/125; C04B2237/126; C04B2237/30; C04B2237/32; C04B2237/34; C04B2237/343; C04B2237/40; C04B2237/403; C04B2237/405; C04B2237/406; C04B2237/407; C04B2237/50; C04B2237/70; C04B2237/708; C04B2237/72; C04B2237/76; F; F01; F01M; F01M1/00; F01M1/08; F01M2001/086; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49124; Y10T29/49147; Y10T29/49149

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 123 words
A method of connecting a metal conductor to a ceramic substrate in an IC package used in high frequency bands on the order of several GHz, said method comprising the steps of: providing a terminal portion on the ceramic substrate, the ceramic substrate having a dielectric constant of less than or equal to 7.0 and a coefficient of thermal expansion of 5×10 -6 /°C. or less; forming a barrier layer on the terminal portion of the ceramic substrate, the barrier layer consisting essentially of a material selected from the group consisting of Ni, Pd, and Pt; and brazing a metal conductor to the terminal portion of the ceramic substrate through the barrier layer with a brazing filler material consisting essentially of pure Ag.
Claim 2
Independent Claim 123 words
A method of connecting a metal conductor to a ceramic substrate in an IC package used in high frequency bands on the order of several GHz, said method comprising the steps of: providing a terminal portion on the ceramic substrate, the ceramic substrate having a dielectric constant of less than or equal to 7.0 and a coefficient of thermal expansion of 5×10 -6 /°C. or less; forming a barrier layer on the terminal portion of the ceramic substrate, the barrier layer consisting essentially of a material selected from the group consisting of Ni, Pd, and Pt; and brazing a metal conductor to the terminal portion of the ceramic substrate through the barrier layer with a brazing filler material consisting essentially of pure Ag.
Claim 3
Dependent Claim 14 words
The method of claim 1, wherein said barrier layer is about 10 μm thick.
Claim 4
Dependent Claim 19 words
The method of claim 2, wherein said brazing step takes place at a brazing temperature of approximately 1000° C.

References Cited (Backward Citations)

CA556614A Cited
US3649803A Cited
US3862488A Cited
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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) 1992-01-31 1992-08-01 1993-01-31 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-01-31 1996-08-01 1997-01-31 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-01-31 2000-08-01 2001-01-31 $7700.00 Window Closed / Lapsed

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