Method of making an electrically insulative substrate Patent #: 4572754
ApplicationNo. 06/775386 filed on 09/12/1985
US Classes:428/201, Intermediate layer is discontinuous or differential174/256, With particular material257/E23.006, Metallic substrates having insulating layers (EPO)428/209, Including metal layer428/210, Including ceramic, glass, porcelain or quartz layer428/901, PRINTED CIRCUIT442/16Including a preformed film, foil, or sheet
ExaminersPrimary: Cannon, James C.
Attorney, Agent or Firm
International ClassesC03C 14/00 (20060101)
C04B 33/00 (20060101)
C04B 33/26 (20060101)
C04B 33/36 (20060101)
H05K 1/05 (20060101)
H01L 21/02 (20060101)
H01L 23/14 (20060101)
H01L 23/12 (20060101)
H01L 21/48 (20060101)
H05K 1/09 (20060101)
AbstractAn apparatus for fabricating composite porcelain substrates employing alternating layers of wire cloth and porcelain green sheet material is disclosed, wherein those alternating layers are compressed toward one another at a somewhat elevated temperature and then kiln fired at a further elevated temperature to form a glazed porcelain surface for receiving further electrical circuitry, for example, of the microelectronic type. Such a composite porcelain substrate has good thermal properties of high conductivity and low coefficient of expansion as well as good electrical insulating properties and mechanical strength. In particular its thermal expansion properties are well matched to many surface mounted devices that may be placed on the substrate thereby reducing the likelihood of thermal damage of device connections. The substrate cost is very low in comparison to the currently available alternatives.