ABSTRACT
The techniques which are of particular interest for the deposition of polycrystalline thin films for microelectronic devices are evaporation, sputtering and chemical vapour deposition. The basic principle of film deposition by evaporation is that increasing the temperature of a material will increase its equilibrium vapour pressure. The precise stoichiometry of the evaporated film will depend on the vapour pressures of the various evaporant elements over the source. The principle of sputter deposition is quite different to that of thermal evaporation. The chapter shows that defect concentrations in thin films can be very much higher than in bulk materials. It considers the additional possibility that phases exist in thin films which are not found in the equilibrium phase diagram. The chapter describes the numerous experiments have demonstrated that considerable concentrations of oxygen can be found at the grain boundaries in refractory metal films deposited by all the vapour phase growth techniques.
