TiO₂ Thin Films Formed by Electron Cyclotron Resonance Plasma Oxidation at High Temperature and Their Application to Capacitor Dielectrics

Abstract

Low-leakage-current rutile- TiO 2 thin films were fabricated by electron cyclotron resonance (ECR) plasma oxidation of Ti thin films. Rutile- TiO 2 thin films could be obtained at substrate temperatures above 280°C. A relative dielectric constant of about 120 was obtained at substrate temperatures above 390°C. Leakage current characteristics of the TiO 2 thin films were improved by using high-temperature plasma oxidation and high-work-function electrodes. A leakage current of less than 1×10 -8 A/cm 2 at an applied voltage of 1.25 V was obtained for a Au/TiO 2 /Pt capacitor with SiO 2 equivalent thickness of 4.9 nm.