Optical properties of tensile-strained and relaxed Ge films grown on InGaAs buffer

V. A. Volodin (1, 2) , L. V. Sokolov (2) , M. A. Pytyato (2) , N. I. Petikov (2) , Mathieu Stoffel (3) , Hervé Rinnert (3) , Michel Vergnat (3)

1 NSU - Novosibirsk State University
2 A.V. Rzhanov Institute of Semiconductor Physics
3 IJL - Institut Jean Lamour

GeO2/Ge/InxGa1-xAs heterostructures grown on (100) GaAs substrates were studied using Raman spectroscopy and photoluminescence (PL) spectroscopy. Both nearly pseudomorphic tensile-strained and nearly completely relaxed Ge films were grown and studied. The maximum tensile strain for Ge films with a thickness of approximate to 7 nm reaches 2.25%. PL data confirm the conclusions that the band gap offset of Ge/InxGa1-xAs is sensitive to the polarity of the bonds at the interface, and also to a parameter of x and the relaxation of strain. Depending on these parameters, the Ge/InxGa1-xAs may be type-I or type-II heterostructures.

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

V. A. Volodin, L. V. Sokolov, M. A. Pytyato, N. I. Petikov, Mathieu Stoffel, et al.. Optical properties of tensile-strained and relaxed Ge films grown on InGaAs buffer. Journal of Applied Physics, 2014, 115 (5), ⟨10.1063/1.4864466⟩. ⟨hal-01284791⟩