Optimization of scandium oxide growth by high pressure sputtering on silicon

• Published in: Thin solid films Vol. 526; pp. 81 - 86
• Main Authors: Feijoo, P.C., Pampillón, M.A., San Andrés, E., Lucía, M.L.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 30.12.2012; Elsevier
• Subjects: Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Deposition; Deposition by sputtering; Electric potential; Exact sciences and technology; High pressure sputtering; High-k dielectrics; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Management information systems; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Optical instruments, equipment and techniques; Physics; Polarimeters and ellipsometers; Scandium oxide; Scandium oxides; Silicon; Sputtering; Structure and morphology; thickness; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Theory and models of film growth; Thin film structure and morphology; Thin films; Voltage; High-k dielectrics; High pressure sputtering; Scandium oxide; Fourier transform spectroscopy; Pressure effects; Growth rate; XRD; Optimization; Sputtering; CV characteristic; Thin films; Hysteresis loop; Gallium tellurides; Silicon; Damage; Defect density; Electronic properties; Semiconductor materials; Electrical properties; Aluminium; Infrared spectra; Layer thickness; Ellipsometry; High pressure; Interfaces; Transmission electron microscopy; Silicon oxides; Growth mechanism; High k dielectric; MIS devices; Gates
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2012.11.008

This work demonstrates the viability of scandium oxide deposition on silicon by means of high pressure sputtering. Deposition pressure and radio frequency power are varied for optimization of the properties of the thin films and the ScOx/Si interface. The physical characterization was performed by ellipsometry, Fourier transform infrared spectroscopy, x-ray diffraction and transmission electron microscopy. Aluminum gate electrodes were evaporated for metal–insulator–semiconductor (MIS) fabrication. From the electrical characterization of the MIS devices, the density of interfacial defects is found to decrease with deposition pressure, showing a reduced plasma damage of the substrate surface for higher pressures. This is also supported by lower flatband voltage shifts in the capacitance versus voltage hysteresis curves. Sputtering at high pressures (above 100Pa) reduces the interfacial SiOx formation, according to the infrared spectra. The growth rates decrease with deposition pressure, so a very accurate control of the layer thicknesses could be provided. ► Scandium oxide is considered as a high permittivity dielectric. ► Scandium oxide was deposited on Si by high pressure sputtering. ► Characterization was performed for deposition condition optimization. ► High deposition pressures showed higher film and interface quality.