A STUDY ON THE SURFACE-STRUCTURE OF TI CATHODE AND THE MACROPARTICLE OF TIN FILMS PREPARED BY THE ARC ION PLATING PROCESS

Previously, we reported that the increase in the rotational velocity o f the Ti cathode reduces the number of macroparticle on the TiN film s urface in the are ion plating (AIP) process. In this study, we investi gated the relation between the behaviors of cathode spot on the rotati ng cathode and the occurrence of macroparticles, In order to examine t he effect of cathode spot on the surface structure of the cathode, the surface topographies of the Ti cathodes used to different extent were measured with a laser microscope. In addition, using a video tape rec order (VTR), the complicated behavior of cathode spots were observed d uring the AIP process as a function of the rotational velocity of the cathode target. The discontinuous and intermittent spots were found to jump, split and recombine with each other on the surface. With increa sing rotational velocity, the spots tended to become stationary exhibi ting circles. The increase in the rotational velocity seems to acceler ate the drift velocity of the spots and to reduce the current density at microprotrusions with extremely high electric field densities, whic h may result in the reducing occurrence of macroparticles.