Effects of Ion Irradiation on Formation of TiO₂ Thin Films by Reactive Sputtering in Electron Cyclotron Resonance Plasma Source

Abstract

We have studied the effects of ion irradiation on the growth of sputtered TiO₂ thin films in an electron cyclotron resonance (ECR) sputtering system. In the ECR sputtering system, divergent magnetic fields were formed by the external permanent magnets whose N poles faced each other. Microwave of 2.45-GHz frequency was launched from a slot antenna between the magnets through a quartz window. Ti metal target was settled in the sputtering system. Thin films of TiO₂ were deposited on a glass substrate. The plasma generated flowed to the side-walls along the divergent magnetic fields. The substrate was bombarded by the plasma during the film growth. A plasma shutter was placed against the plasma flow. It was found that the plasma shutter affected the crystal structure of the sputtered TiO₂ thin films : Rutile and anatase TiO₂ thin films were grown with the shutter opened and closed, respectively.