Effect of plasma operation pressure on burn-in efficiency of an SIP-PVD chamber

The effect of the plasma operation pressure on the burn-in efficiency of a self-ionized-plasma (SIP) physical vapor deposition (PVD) system for growing TiN liner films was examined. The experiments in this study were designed to obtain the proper plasma operation pressure and to set up a simplified procedure for optimization of the productivity and yield. Our results indicated that the number of particles falling on the wafer started to decrease when increasing the burn-in plasma pressure above 10 mTorr and a comparatively stable condition could be maintained at a high burn-in plasma pressure over 20 mTorr. It is believed that the increase of Ar pressure can influence the plasma spatial distribution within the chamber, and thereby enable the plasma to eliminate the particle sources concealed in the chamber narrow space. By proper Ar pressure the conventional burn-in procedure could be simplified without changing the TiN film properties. The simplified burn-in method can not only enhance the front-end yield, but it can also benefit the cost and productivity for production line consideration.