An effect of preheat-treatment on the formation of titanium-oxide films by sintering a titanium/silicon-oxide structure in an oxygen atmosphere

Abstract

Titanium-dioxide (TiO 2) films with a rough surface was grown on silicon by heating a structure of titanium/silicon-oxide/silicon in oxygen at 1000 °C. The TiO 2 film growth is attributed to differences in the Gibbs free energy between the titanium-dioxide and the silicon-oxide. Lower temperature preheating of the titanium/silicon-oxide/silicon structure before the solid-phase reaction was favorable for preparing TiO 2 films with a smooth surface on silicon. The grown films were preferentially (110) orientated rutile-TiO 2 polycrystals containing TiSi and TiO phases. A titanium-silicide layer formed near the interface between titanium-oxide and the silicon was employed as a suitable electrode of the capacitors fabricated with the titanium-oxide films. Titanium-oxide films formed by preheating at 400 °C had high dielectric constants ɛ 0 of (20–25), resistivities of about 4 × 10 10 Ω cm, and a breakdown field around 10 6 V/cm.