VACUUM-ARC DEPOSITION OF TI FILMS WITH TRANSVERSE CURRENT INJECTION

The influence of imposing an electrical field parallel to the substrat e of a growing metallic film was studied experimentally and analyzed t heoretically. Ti films were deposited onto glass substrates using a fi ltered vacuum are source while a voltage U of 0-300 V was applied betw een electrodes spaced 16 mm apart on the substrate surface. The curren t through the film was monitored during the deposition. Several charac teristic stages of current evolution were observed after are initiatio n: (1) an initial sharp jump of the current, (2) a stage of constant, relatively low current, (3) rapid current growth, (4) slower current g rowth, and (5) linear growth. Analyses showed that stages (1) and (2) are connected with current conduction through the plasma rather that t hrough the sample while stages (3) and (4) are connected with tunnelin g and percolation during film formation. The tunneling stage could be distinguished only for U less than or equal to 6 V; in other cases, co nduction through the plasma obscured the observation. The percolative exponent increased from 1.0 to 2.68 and the critical thickness decreas ed by a factor of 4.3 with an increased U from 1 to 60 V. (C) 1997 Ame rican Institute of Physics.