Properties of MgTiO₃ thin films prepared by RF magnetron sputtering for microwave application

The crystal structure and dielectric characteristics of MgTiO₃ films were investigated. In this work, MgTiO₃ thin films were fabricated on n-type Si(1 0 0) substrates by reactive RF magnetron sputtering at various Ar/O₂ mixing ratios (100/0, 90/10, 80/20) and substrate temperatures (200, 300 and 400 °C), at an RF power of 400 W. Highly oriented MgTiO₃(1 1 0) thin films were obtained at an RF power of 400 W and substrate temperatures of 200, 300 and 400 °C and various Ar/O₂ ratios (100/0, 90/10, 80/20). These conditions are much colder than the bulk sintering temperature. These films were investigated at an RF of 400 W and various substrate temperatures. The microstructure and surface morphology of the MgTiO₃ films deposited on n-Si(1 0 0) were observed by X-ray diffraction (XRD) scanning electron microscopy (SEM) and atomic force microscopy (AFM). The XRD showed that the deposited films exhibited a polycrystalline microstructure. The grain size of the film increased with the substrate temperature. The electrical properties were measured by making C-V and current-voltage I-V measurements on metal-insulator-semiconductor (MIS) capacitor structures. At an RF power of 400 W and a substrate temperature of 400 °C, the dielectric constant was 16.2 (f=10MHz).