Asymmetric bipolar pulsed DC: the enabling technology for reactive PVD

The use of reactive DC sputtering for the deposition of insulators from conductive targets has been limited by the intrinsic problem of target poisoning and the consequent arcing and process instabilities. The need to deposit high quality dielectric films rapidly is becoming more important as technology pushes forward. Asymmetric bipolar pulsed DC eliminates target poisoning through preferential sputtering, enabling existing PVD tools to produce the high-quality, low-defect dielectric films needed for next generation processes. Typical films being produced with asymmetric bipolar pulsed DC from metallic targets include Al2O3, AlN, SiO2, SiN, Ta2O3, DLC, TaN, TiN and ITO. The mechanisms of target poisoning and dielectric arcing are explained in this paper, and solutions are given. (C) 1998 Published by Elsevier Science S.A.