Growth and Characterization of Ti-Ta-O Thin Films on Si Substrates by Liquid Injection MOCVD for High-k Applications from Modified Titanium and Tantalum Precursors

Titanium oxide (TiO(2)) and titanium-tantalum oxide (Ti-Ta-O) thin films are deposited by liquid injection (LI) metal-organic (MO) CVD using metal amide-malonate complexes, [Ti(NR(2))(2)(dbmI)(2)], and tantalum, [Ta(NMe(2))(4)(dbml)] (R = Me, Et; dbml = di-tert-butylmalonato). TiO(2) and Ti-Ta-O films are deposited on Si (100) in the temperature ranges 350-650 degrees C and 500 - 700 degrees C, respectively. The structure, morphology, and chemical composition of the films are evaluated by X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), Rutherford backscattering spectroscopy (RBS), and X-ray photoelectron spectroscopy (XPS). The electrical properties of the films, namely the dielectric properties, are assessed by carrying out capacitance-voltage (C-V) measurements on metal-oxide-semiconductor (MOS) capacitor structures.