Patent US4615936A successfully refreshed from Google Patents.
EP0092912A2
Expired / Lapsed
EP
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Multilayer ceramic dielectric capacitors
Assignee: STC PLC
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Filing: 1983-03-29
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Granted: —
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Expires: 2003-03-29
Abstract
Abstract Conductive and porous end terminations for metal- impregnated multilayer ceramic dielectric capacitors are provided by firing a silver, or silver alloy, and glass frit onto respective end regions of a sintered capacitor stack. The exposed silver of the fired terminations is provided with a silver sulphide layer, the latter being a good electrical conductor and acting as a barrier between the silver and the impregnation metal, for example lead, during a subsequent impregnation step, whereby to prevent leaching of the silver. The termination is readily solderable by virtue of the silver sulphide layer being wetted by the lead during the impregnation step and resulting in a lead coating in the termination.
Inventors
- 👤 John Henry Alexander
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 02:28
CPC Classifications
H; H01; H01G; H01G4/00; H01G4/002; H01G4/228; H01G4/232; H01G4/2325; Y; Y10; Y10T; Y10T29/00; Y10T29/43; Y10T29/435
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
58 words
A method of manufacturing an electrical component comprising providing an insulating substrate, forming a connection termination on the substrate by firing a frit containing glass and silver or silver alloy thereon, and forming an electrode of the electrical component in contact with the termination, characterised by forming a silver sulphide layer on the exposed silver of the termination.
Claim 2
Independent Claim
58 words
A method of manufacturing an electrical component comprising providing an insulating substrate, forming a connection termination on the substrate by firing a frit containing glass and silver or silver alloy thereon, and forming an electrode of the electrical component in contact with the termination, characterised by forming a silver sulphide layer on the exposed silver of the termination.
Claim 3
Independent Claim
61 words
A method of manufacturing a multilayer ceramic dielectric capacitor including the steps of applying a frit containing glass and silver or silver alloy to end faces of the capacitor to which electrodes of the capacitor extend, and firing the frit to provide silver containing end terminations, characterised by providing the exposed silver of the end terminations with a silver sulphide layer.
Claim 4
Independent Claim
61 words
A method of manufacturing a multilayer ceramic dielectric capacitor including the steps of applying a frit containing glass and silver or silver alloy to end faces of the capacitor to which electrodes of the capacitor extend, and firing the frit to provide silver containing end terminations, characterised by providing the exposed silver of the end terminations with a silver sulphide layer.
Claim 5
Dependent Claim
40 words
A method as claimed in claim 2, characterised in that the capacitor is impregnated with metal electrode material after the provision of the silver sulphide layer, which metal electrode material connects directly with the fired frit at the end faces.
Claim 6
Dependent Claim
32 words
A method as claimed in claim 3, characterised in that the metal electrode material is lead and that during the impregnation step a lead layer is formed on the silver suphide layer.
Claim 7
Independent Claim
25 words
A method as claimed in any one of claims 2 to 4, characterised in that the frit is fired at a temperature up to 800°C.
Claim 8
Independent Claim
35 words
A method as claimed in any one of the preceding claims, characterised in that the silver sulphide layer is provided by contacting the exposed silver of the end terminations with hydrogen sulphide or sulphur vapour.
Claim 9
Dependent Claim
50 words
A method as claimed in claim 6 as appendant to claim 2, characterised in that prior to contacting with the hydrogen sulphide or suphur vapour, air is evacuated from any voids in the capacitors and the end terminations and the capacitors are heated to a temperature in the range 350-400°C.
Claim 10
Dependent Claim
25 words
A method as claimed in claim 4, characterised by the further step of soldering connection wires to the end terminations after the lead impregantion step.
Claim 11
Dependent Claim
19 words
A multilayer ceramic dielectric capacitor made by a method as claimed in any one of claims 2 to 8.
References Cited (Backward Citations)
No citation records indexed.
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