ABSTRACT
This chapter provides tabulated electrical, mechanical, and thermal data for many of the materials commonly used at various levels of packaging. Thermal, mechanical, and electrical data and applications information are tabulated for semiconductor materials, substrates, joining materials, encapsulants, enclosures, and contact/conductor materials. Materials are classified as semiconductors because of their unique electrical behavior. In defining a semiconductor it is useful to begin by thinking about a metal. In certain applications where electrical conductivity is required, metals are selected as chip carrier materials. Polyimide- and polytetrafluoroethylene-based systems are selected for their superior thermal or electrical characteristics. The electronic structure of semiconductors gives rise to mechanical and thermal properties important to the packaging engineer. The properties of the material will vary with the orientation of the crystal. In semiconductors and insulators, the valence band is filled and there are no immediately available states for the electrons to occupy.
