Abstract: A printed wiring board laminate is disclosed that is particularly suitable for use with leadless surface mounted devices such as ceramic chip carries. The laminate combines a low coefficient of thermal expansion in the X-Y direction with thermal conductivity. In one embodiment, the laminate comprises a support fabricated from graphite fiber reinforced metal adhesively secured to a printed wiring board fabricated from dielectric (e.g., glass) fiber reinforced resin. The support has an X-Y coefficient of thermal expansion less than about 4 ppm/.degree.C., and the printed wiring board has a coefficient of thermal expansion greater than about 10 ppm/.degree.C. In a second embodiment, the support comprises a core of graphite fiber reinforced metal or resin sandwiched between two metal sheets.

Abstract: A composite printed wiring board is provided wherein the surface of the board is fabricated from conventional fiber reinforced plastic laminates such as glass fiber reinforced epoxy laminates and that laminate is secured by means of a thermoset adhesive to a support member which is fabricated from graphite filament reinforced thermoset resin having a low coefficient of thermal expansion approaching zero. The unrestrained coefficient of thermal expansion of the printed wiring board is significantly greater than that of the support member. However, in the composite assembly, the apparent coefficient of thermal expansion of the printed wiring board is greatly reduced and can approximate the coefficient of thermal expansion of a ceramic chip carrier. The coefficient of thermal expansion of the printed wiring board in its thickness direction is only slightly reduced in the composite assembly.