Impact of a γ-Al₂O₃(001) barrier on LaAlO₃ metal-oxide-semiconductor capacitor electrical properties

L. Becerra (1) , C. Merckling , M. El-Kazzi , N. Baboux (2) , B. Vilquin (3) , Guillaume Saint-Girons (3) , C. Plossu (2) , G. Hollinger (3)

1 INSP - Institut des Nanosciences de Paris
2 INL - DE - INL - Dispositifs Electroniques
3 INL - H&N - INL - Hétéroepitaxie et Nanostructures

Amorphous LaAlO3 high-κ oxides were grown in a molecular beam epitaxy reactor on p-Si(001) employing a thin γ-Al2O3 epitaxial layer as buffer. Interfaces are free of SiO2 and silicates and remain abrupt even after high temperature annealing as demonstrated by x-ray photoelectron spectroscopy. Electrical measurements performed on as-deposited samples reveal dielectric constant values close to the bulk ones, small equivalent oxide thickness, and low interface state densities. Some negative charges are present leading to a flatband voltage shift. Postdeposition annealing can correct this effect.

Domaines: Science des matériaux [cond-mat.mtrl-sci]

L. Becerra, C. Merckling, M. El-Kazzi, N. Baboux, B. Vilquin, et al.. Impact of a γ-Al₂O₃(001) barrier on LaAlO₃ metal-oxide-semiconductor capacitor electrical properties. Journal of Vacuum Science & Technology B Microelectronics and Nanometer Structures, 2009, 27 (1), pp.384-388. ⟨10.1116/1.3065437⟩. ⟨hal-01939927⟩