Structural and electrical properties of radio frequency magnetron sputtered tantalum oxide films: Influence of post-deposition annealing

• Published in: Materials science in semiconductor processing Vol. 13; no. 4; pp. 245 - 251
• Main Authors: Jagadeesh Chandra, S.V., Choi, Chel-Jong, Uthanna, S., Mohan Rao, G.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.12.2010; Elsevier
• Subjects: Annealing; Applied sciences; Cold working, work hardening; annealing, quenching, tempering, recovery, and recrystallization; textures; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Density; Deposition by sputtering; Dielectric properties of solids and liquids; Dielectrics, piezoelectrics, and ferroelectrics and their properties; Electrical properties; Exact sciences and technology; Heat treatment; Magnetic properties; Materials science; Metals. Metallurgy; Metal–insulator–semiconductor structure; Methods of deposition of films and coatings; film growth and epitaxy; Permittivity (dielectric function); Physics; Production techniques; Radio frequencies; Semiconductors; Sputtering; Tantalum oxide; Tantalum oxides; Treatment of materials and its effects on microstructure and properties; X-rays; Tantalum oxide; Electrical properties; Sputtering; Metal–insulator–semiconductor structure; Beta phase; Electrical conductivity; Annealing temperature; Leakage currents; Cathode sputtering; Microelectronic fabrication; Bias voltage; Permittivity; Current density; Radiofrequency sputtering; Electrical characteristic; Annealing; Gate voltage; Tantalum capacitor; Electrical conduction; Radiofrequency; Sandwich structures; Magnetrons; Metal-insulator-semiconductor structure; Orthorhombic lattices; Reactive sputtering; X ray diffractometry; X-ray photoelectron spectra
• ISSN: 1369-8001; 1873-4081
• DOI: 10.1016/j.mssp.2010.08.002

The as-deposited and annealed radio frequency reactive magnetron sputtered tantalum oxide (Ta 2O 5) films were characterized by studying the chemical binding configuration, structural and electrical properties. X-ray photoelectron spectroscopy and X-ray diffraction analysis of the films elucidate that the film annealed at 673 K was stoichiometric with orthorhombic β-phase Ta 2O 5. The dielectric constant values of the tantalum oxide capacitors with the sandwich structure of Al/Ta 2O 5/Si were in the range from 14 to 26 depending on the post-deposition annealing temperature. The leakage current density was <20 nA cm −2 at the gate bias voltage of 0.04 MV/cm for the annealed films. The electrical conduction mechanism observed in the films was Poole–Frenkel.