ION-ASSISTED DEPOSITION WITH A NEW PLASMA SOURCE

Ion-assisted deposition is a well-known technique to improve the properties of thin films. One disadvantage of this technology is the small useful substrate area compared to conventional evaporation. Therefore we have developed a new plasma source which is able to irradiate large substrate holders (1 m diameter) with a high plasma current density. The principle of operation and some details of the plasma source are described. The experiments were done in a conventional coating system. The plasma source has been operated up to 80 V discharge voltage and up to 70 A discharge current. For single layers of TiO2 we have found two different modifications with refractive indices of 2.37 and 2.6 with a high packing density. The spectral curves exhibit no shift after keeping samples under water and after baking (250-degrees-C).