Thermally induced permittivity enhancement in La-doped ZrO2 grown by atomic layer deposition on Ge(100)

L. Lamagna , C. Wiemer , S. Baldovino , A. Molle , M. Perego , Sylvie Schamm-Chardon (1) , Pierre-Eugène Coulon (1) , M. Fanciulli (2)

1 CEMES - Centre d'élaboration de matériaux et d'études structurales
2 Dipartimento di Scienza dei Materiali

La-doped ZrO2 thin films grown by O3-based atomic layer deposition directly on Ge(100) exhibit a dielectric constant of 29. Upon annealing in N2 at 400 °C, a high κ value >40 is extracted for film thickness below 15 nm. Compositional depth profiling allows to correlate this observation with a remarkable Ge interdiffusion from the substrate which is consistent with the stabilization of the tetragonal ZrO2 phase. Ge interaction with the oxide stack and the formation of a germanate-like interfacial region, which acts as an electrical passivation for the Ge surface, are also investigated.

Domaines: Physique [physics]; Science des matériaux [cond-mat.mtrl-sci]; Micro et nanotechnologies/Microélectronique

L. Lamagna, C. Wiemer, S. Baldovino, A. Molle, M. Perego, et al.. Thermally induced permittivity enhancement in La-doped ZrO2 grown by atomic layer deposition on Ge(100). Applied Physics Letters, 2009, 95 (12), pp.122902. ⟨10.1063/1.3227669⟩. ⟨hal-01745026⟩