Electrical and optical experimental study of ionized physical vapour deposition (IPVD) processes

This paper deals with the diagnostics of an IPVD process called Highly Ionized Sputter Deposition Process (HISDP) using a high power pulsed magnetron plasma. The HISDP plasma was spatially and temporally characterized in the post-discharge using optical absorption spectroscopy and Langmuir probe time resolved measurements. A circular titanium target was used and the buffer gas was argon. The titanium densities (neutrals and ions) were measured by pulsed resonant absorption spectroscopy technique. The comparison between the experimental results and a simple one-dimensional (1D) model of diffusion shows that the transport of neutral and ionized sputtered atoms is mainly controlled by diffusion for a pressure of 4 Pa (classical for neutrals and ambipolar for ions). Moreover, the limits of the optical absorption spectroscopy technique are investigated at lower pressures.