A MODEL FOR REACTIVE MAGNETRON SPUTTERING

A steady-state model for the reactive sputtering process in a symmetrical planar magnetron configuration is presented which takes the specific system geometry into consideration. Further to the simulation of the well-known hysteresis effect and its consequences in the composition of the composition of the deposited film, the model allows for the calculation of the radial compositional distribution of the growing film as a function of the distance between the target and the condensation surface. The proposed model introduces a reactive gas profile across the reaction zone (instead of considering it to be constant), to account for the gettering action of both the magnetron target and condensation surface at relatively high sputtering rates and short target-to-substrate separations. The possibility of introducing reactive gas through the centre of the magnetron surface is also examined and the effects on the stoichiometry of the film as well as on the stability of the system are presented.