Ceramic and glass insulation in data processing equipment

The properties of currently available glass and ceramic insulation used for substrate applications have been presented. The degree to which these materials meet the desired property goals has been discussed. It is concluded that improvements during the past two years have been significant in matching available substrate properties to those desired. In the field of ceramic substrates physical tolerances have been reduced by a factor of two, while size limits have been increased from about 6 square inches to 20 square inches. Research programs are being pursued which have improved unglazed surface finishes from about 20 microinches to 10 micro-inches. Glaze uniformity has also been improved and it is anticipated that further progress will be forthcoming in this area. A solution to the costly problem of current separation when large ceramic substrates are used is probably this year.