Effects of sputtering pressure and post-metallization annealing on the physical properties of rf-sputtered Y 2O 3 films

Abstract

Y 2O 3 thin films were prepared by rf-sputtering under various sputtering pressures at room temperature. Spectroscopic ellipsometer, X-ray diffraction and semiconductor parameter analyzer were used to characterize the studied films. The results show the crystallinity and leakage current density of the films improved with decreasing sputtering pressure. The effects of post-metallization annealing (PMA) on optical, structural and electrical properties of the films were also evaluated. It is found that PMA can significantly enhance the electrical performance of Y 2O 3 film, and the lowest leakage current is found to be 1.54 × 10 −8 A/cm 2 at 1 MV/cm for the samples treated at 350 °C for 30 min. The leakage current mechanisms were discussed as well, which reveals that space charge limited current dominates the as-deposited films while Schottky mechanism describes the PMA treated ones well.