Materials Science concepts for printed films

The chapter examines some illustrative cases of the complex interplay between the composition process and properties relations in simple printed film structures, such as resistors and interconnections. It is remarked that thermodynamics data can help, in some cases, in interpreting film phase stability, but richer information would be required to understand the complex phenomena that may occur in thick-printed films, which are typically systems far from thermal equilibrium. Examples of interactions that impact on the films' electrical properties are reported. It is remarked that the microstructure and performance of thick-films start to evolve from temperatures as low as room temperature and continue to change during the whole course of processing or, when required, in post-process thermal annealing. It is shown that the presumed ideal picture of cermet systems consisting of single-phase conducting particles imbedded in vitreous phase is very far from the reality.