Changing TiN film morphology by “plasma biasing”

The influence of the substrate potential with respect to the plasma on the morphology of reactively sputtered TiN thin films on Si(100) has been investigated. It is well known that the film quality with respect to grain size and distribution can be improved by applying a negative substrate bias to increase energetic ion bombardment. For large-area applications, however, a grounded substrate is very much desirable. Therefore, a technique has been developed to deposit films with comparably improved morphology on grounded substrates by means of a so-called “plasma electrode.” Grain size and distribution have been analyzed by top- and side-view scanning electron microscopy. To adjust the parameters for the TiN deposition we have used in situ photoelectron spectroscopy as the process control.