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EP0247617A2 Expired / Lapsed EP ⏱️ 0.0 years remaining

Multilayer ceramic substrate with circuit patterns

Assignee: Narumi China Corp
•
Filing: 1987-05-27
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Granted: —
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Expires: 2007-05-27
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Abstract

Abstract A multilayer ceramic substrate with circuit patterns in which Ag conductor patterns having a sheet resistivity lower than 3 milliohms/square are formed inside the substrate by co-firing with green ceramic sheets and Au conductor patterns are formed onto the surface of the substrate in such a way that said Au conductor patterns are electrically connected with said Ag conductor patterns. In such an arrangement, high reliable multilayer substrates can be readily obtained without increasing production cost, while maintaining superior properties of Au. If desired, a metal layer different from the foregoing conductor patterns may be interposed between the Ag conductor pattern and the Au conductor pattern. The metal layer prevents diffusion of Ag to the Au conductor patterns and provides much higher improvements anti-migration property and reliability.

Inventors

  • 👤 Susumu Nishigaki
  • 👤 Shinsuke Yano
  • 👤 Hiroshi Corpo Tokai 101 Kawabe
  • 👤 Toshio Nonomura

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-03 20:28
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/22; H05K3/24; H05K3/245; H05K3/247; H05K3/248; H10; H10W; H10W70/00; H10W70/01; H10W70/05; H10W70/60; H10W70/611; H10W70/62; H10W70/66; H10W70/67; H10W70/68; H10W70/685; H10W72/00; H10W72/30; H05K3/46; H05K3/4611; H05K3/4626; H05K3/4629; H10W72/071; H10W72/073; H10W72/07331; H10W72/07336; H10W72/075; H10W72/07531; H10W72/07532; H10W72/07533; H10W72/50; H10W72/551; H10W72/552; H10W72/5522; H10W72/851; H10W72/874; H10W72/884; H10W90/00; H10W90/701; H10W90/731; H10W90/734; H10W90/751; H10W90/754

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 60 words
A multilayer ceramic substrate with circuit patterns in which Ag conductor patterns having a sheet resistivity lower than 3 milliohms/square are formed inside said substrate by co-firing with green ceramic sheets and Au conductor patterns are formed onto the surface of said substrate in such a way that said Au conductor patterns are electrically connected with said Ag conductor patterns.
Claim 2
Dependent Claim 60 words
A multilayer ceramic substrate with circuit patterns in which Ag conductor patterns having a sheet resistivity lower than 3 milliohms/square are formed inside said substrate by co-firing with green ceramic sheets and Au conductor patterns are formed onto the surface of said substrate in such a way that said Au conductor patterns are electrically connected with said Ag conductor patterns.
Claim 3
Dependent Claim 39 words
A multilayer ceramic substrate as claimed in Claim 1 in which said Ag conductor patterns contain at least one selected from the group consisting of Pd, Pt and Rh in amounts of 2% or less, in additon to Ag.
Claim 4
Dependent Claim 36 words
A multilayer ceramic substrate as claimed in Claim 1 in which said Ag conductor patterns and said Au conductor patterns are electrically connected through a different metal layer interposed between said two kinds of conductor patterns.
Claim 5
Dependent Claim 23 words
A multilayer ceramic substrate as claimed in Claim 3 in which said different metal layer is formed from Ni, Cr, Ti or Pd.

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