Oxygen CCP global model for investigate the influence of plasma power on PEALD TiO2 thin film properties

In this study, we use a global model to investigate the oxygen plasma cycle of PEALD of TiO2 thin films. The reactor geometry is an asymmetric capacitive coupled (CCP) radio frequency discharge and it was investigated the effect of discharge power in the range of 10-500 W, for a working pressure of 1.0 mbar, on plasma parameters: neutral and ion species densities. These are typical conditions for PEALD process. The global model assumes that the discharge contains several species such as O2 , O, electrons, ground state O2 and O atoms, and O2(a Δg) metastable. In parallel we have investigated the growing of TiO2 thin films onto Si(100) by PEALD using TTIP and oxygen plasma. Oxygen plasma power was varied from 50-200 W for a fixed temperature of 250oC and the as-deposited TiO2 thin films were investigated regarding its structure and morphology. From global model results, it was possible to infer the main species that can achieves the substrate and correlate the as-deposited TiO2 thin film analyses in order to explain the effect of discharge power in film crystallinity and morphology.