Thin film processing by radio frequency hollow cathodes

The main features of the radio frequency (RF) hollow cathodes for thin film processing are summarized. The utilization of cylindrical RF hollow cathodes in both the plasma-enhanced chemical vapour deposition (PECVD) and the physical vapour deposition (PVD) of films is reviewed. An example of the high rate PECVD of Si-N films is described in more detail. Gas metastables excited inside the cathode can act as a source of additional heat, thereby enhancing the thermionic electron emission and ionization of the gas. Transition from the glow into a hot cathode are regime is characterized by changes in the plasma parameters and consequently in the growth of films. Examples for PVD of TIN films are shown. Magnetic focusing in the linear are discharge source leads to the formation of linear hot zones at the outlet of the parallel-plate cathode and enables the hollow cathode discharges to be scaled up for large area applications. (C) 1997 Elsevier Science S.A.