Theoretical Model of Plasma Metallization of Ceramic Heat Sinks

This paper reports a theoretical study of the mechanism of adhesion of a plasma metal coating to a ceramic substrate by an example of beryllium oxide. The adhesion mechanism is based on an increase in the concentration of structural defects (vacancies) and electron exchange interaction of a metal-beryllium oxide pair during the plasma thermal activation of the process. The proposed analysis of the substrate boundary conditions on an example of titanium atoms and beryllium oxide justifies the optimal regime of the coating deposition in plasma (heating temperature, deposition time, and activation energy) with the maximum adhesion of the plasma metal coating. It is in good agreement with the experimental studies. According to the analytical calculations, the substrate temperature for an ideal surface as well as the maximum adhesion of the plasma metal coating is 1230 K in the case of beryllium oxide, whereas the experimental temperature is about 1380 K.