The structural and electronic properties of silicene nanosheets epitaxially grown on Ag(111) are systematically investigated by combining scanning tunneling microscopy and scanning tunneling spectroscopy. By carefully tuning the growth parameters, complex 2D silicon structures are obtained, which evidence the presence of corrugated silicene domains. Local modifications of the density of states are observed throughout reconstructed silicene domains and are attributed to the symmetry breaking induced by the interactions with the Ag lattice, in analogy with the case of graphene.

The chemical stability of buckled silicene, i.e., the silicon counterpart of graphene, is investigated then resulting in a low reactivity with O 2 when dosing up to 1000 L and in a progressive oxidation under ambient conditions. The latter drawback is addressed by engineering ad hoc Al-and Al 2 O 3 -based encapsulations of the silicene layer. This encapsulation design can be generally applied to any silicene confi guration, irrespective of the support substrate, and it leads to the fabrication of atomically sharp and chemically intact Al/silicene and Al 2 O 3 /silicene interfaces that can be functionally used for ex situ characterization as well as for gated device fabrication.

We report on zinc oxide thin films grown by atomic layer deposition at a low temperature, which is compatible with a low thermal budget required for some novel electronic devices. By selecting appropriate precursors and process parameters, we were able to obtain films with controllable electrical parameters, from heavily n-type to the resistive ones. Optimization of the growth process together with the low temperature deposition led to ZnO thin films, in which no defect-related photoluminescence bands are observed. Such films show anticorrelation between mobility and free-electron concentration, which indicates that low n electron concentration is a result of lower number of defects rather than the self-compensation effect.

The exposure of Ge(001) substrates to atomic oxygen was studied in situ to establish the stability of the germanium oxide. After preparing chemically clean and atomically flat Ge(001) surfaces, the Ge samples were exposed to atomic oxygen in a wide temperature range from room temperature to 400°C. The chemical composition of the so-formed oxides was studied by means of x-ray photoelectron spectroscopy, while the structure was observed by reflection high energy electron diffraction. At low substrate temperatures the atomic oxygen is efficiently chemisorbed and suboxides coexist with the dioxide, which in turn is remarkably promoted in the high temperature range.

Rare earth oxides could represent a valuable alternative to SiO2 in complementary metal–oxide–semiconductor devices. Lu2O3 is proposed because of its predicted thermodynamical stability on silicon and large conduction band offset. We report on the growth by atomic-layer deposition of lutetium oxide films using the dimeric {[C5H4(SiMe3)]2LuCl}2 complex, which has been synthesized for this purpose, and H2O. The films were found to be stoichiometric, with Lu2O3 composition, and amorphous. Annealing in nitrogen at 950°C leads to crystallization in the cubic bixbyite structure. The dielectric constant of the as-grown Lu2O3 layers is 12±1.