Interface Characterization of Metallized CVD Diamond

Abstract

Progress towards the large scale integration of active devices within electronics packages has imposed stringent heat dissipation requirements necessitating the development of innovative materials solutions. One possibility being considered is the use of chemically vapor deposited diamond (CVDD) thin films as heat sinks. However, there are technological challenges which must be overcome before these materials become commercially viable. For example, the CVDD substrate must be metallized to provide interconnections between the various devices in the package. Conventional metallizations, such as Au, Cu or Al, display poor adhesion to the diamond causing problems associated with the reliability and stability of metallized diamond packages. A novel solution has been proposed involving the consecutive deposition of a thin layer of Cr and an electrically insulating layer of alumina on the diamond substrate such that the thermal conductivity of the treated substrate is not degraded significantly.