Oxidation of Mg atomic monolayer onto silicon: A road toward MgOx/Mg2Si (11–1)/Si (100) heterostructure

Sarpi Brice (1) , Nabil Rochdi (2) , Rachid Daineche (1) , Maxime Bertoglio (1) , Christophe Girardeaux (1) , Alain Baronnet (2) , Jacques Perrin Toinin (1) , Marc Bocquet (1) , Mehdi Djafari-Rouhani (3) , Anne Hémeryck (4) , Sébastien Vizzini (1)

1 IM2NP - Institut des Matériaux, de Microélectronique et des Nanosciences de Provence
2 CINaM - Centre Interdisciplinaire de Nanoscience de Marseille
3 LAAS-N2IS - Équipe Nano Ingénierie et Intégration des Systèmes
4 LAAS-M3 - Équipe Modélisation Multi-niveaux des Matériaux

Surface interfaces of thin magnesium oxide films elaborated onto Si(100)–(2 × 1) substrates were characterized using scanning tunneling microscopy and spectroscopy, Auger electron spectroscopy, atomic force microscopy, and high-resolution transmission electron microscopy. We report that a flat and highly homogeneous magnesium oxide with well-defined interfaces could be grown at room temperature (RT) by repeating alternate adsorption of Mg atomic monolayer and O2 on Si(100). RT oxidation process of the first Mg monolayer plays a crucial role as driving force allowing a partial decomposition of amorphous ultra-thin Mg2Si at the Mg/Si interface to form more magnesium oxide in the surface. This process induces crystallization of the interfacial Mg2Si thin film and then gives arise to an unexpected MgOx/Mg2Si(11–1)/Si(100) heterostructure. MgOx monolayer displays a band gap of about 6 eV and exhibits a weak RMS roughness on large areas.

Domaines: Matériaux

Sarpi Brice, Nabil Rochdi, Rachid Daineche, Maxime Bertoglio, Christophe Girardeaux, et al.. Oxidation of Mg atomic monolayer onto silicon: A road toward MgOx/Mg2Si (11–1)/Si (100) heterostructure. Surface Science Letters, 2015, 642, pp.L1-L5. ⟨10.1016/j.susc.2015.08.003⟩. ⟨hal-01496546⟩