Formation of oxide thin films for optical applications by O/sub 2/-cluster ion beam assisted deposition

The gas-cluster ion beam assisted deposition system has been developed to form oxide thin films with multiple layers. The system is equipped both with an electron beam deposition system and a gas-cluster ion beam system. Our particular attention is focused on an increase in cluster ion current, which enables not only to increase the growth rate but also to widen the growth area. In order to increase the neutral cluster beam intensity, the cluster ion beam system has been designed without adopting the differential pumping system, which was previously inserted between the cluster source and the deposition chamber. The structure and the electrical configuration of the ion source has also been studied to increase the cluster ion beam current. The details of the whole system configuration and the basic characteristics of cluster ion beam production are described. Furthermore, we demonstrate that the indium oxide films with a visibly transparent and atomically smooth surface was obtained successfully at room temperature by using this system.