Patent · US Expired

Ceramic substrate having a protective coating thereon and a method for protecting a ceramic substrate

US5196251A · kind A · utility

43Cited by
10References
29Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 30, 1991
Grant dateMar 23, 1993
Priority date
Expiry dateApr 30, 2011

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/24917
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

Disclosed is a ceramic substrate having a protective coating on at least one surface thereof which includes: PA0 a ceramic substrate having at least one electrically conductive via extending to a surface of the substrate; PA0 an electrically conductive I/O pad electrically connected to at least one of the vias; PA0 an I/O pin brazed to the I/O pad, the brazed pin having a braze fillet; and PA0 a protective layer of polymeric material fully encapsulating the I/O pad, wherein the layer of polymeric material protects the I/O pad from corrosion. Also disclosed is a method of protecting a ceramic substrate from corrosion, the ceramic substrate of the type having a plurality of electrically conductive vias extending to a surface of the substrate, a multilayer metallic I/O pad electrically connected to at least one of the vias, and an I/O pin brazed to the I/O pad, the brazed pin having a braze fillet, the method comprising the step of: PA0 encapsulating fully the I/O pad with a protective layer of polymeric material, wherein the layer of polymeric material protects the I/O pad from corrosion. In a preferred embodiment, the I/O pin is selectively exposed to plasma ashing to remove any err…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.