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The advent of scanning near-field optical microscopy (SNOM) has augmented at a microscopic level the usefulness of optical spectroscopy in the region between 300 nm and 10 mum. Two-dimensional imaging of chemical constituents makes this a very attractive and powerful new approach. In this paper we show SNOM results obtained in several geometrical configurations on boron clusters in silicon, Li clusters embedded in a LiF sample and BN growth on silicon. We also show some results on the wavelength dependence of the reflectivity (R) in the near infrared (IR) of biological cells in liquid environment with the observation of the local fluorescence. The SNOM images revealed features that were not present in the corresponding shear-force (SF) images and which were due to localized changes in the bulk properties of the sample. The size of the smallest detected features clearly demonstrated that near-field conditions were reached both in the visible and infrared region. (C) 2004 Elsevier B.V. All rights reserved.

We investigate the temperature-induced phase transition on Si-terminated β-silicon carbide (SiC)(100) surface using scanning tunneling microscopy (STM) and spectroscopy, and valence band and core level photoemission spectroscopies using synchrotron radiation. Above 700 K, the 2×1 surface exhibits metallization with a non-Fermi liquid power law shape spectral response near the Fermi level. This suggests a surface having one-dimensional (1D) metallicity related to the Si–Si dimers rows constituting the topmost atomic layer. This behavior can be related to the Luttinger liquid model.

We propose a combination of the spectroscopy with infrared radiation emitted by a free-electron laser (FEL) and of a scanning near-field optical microscope (SNOM) to investigate one of the major problems in today's solid state physics: lateral variations of solid interface properties. This approach enabled us to measure the local optical properties of a buried PtSi/Si interface, of diamond grains on top of a silicon surface, of GaAs/AlGaAs wells and of an integrated microcircuit. The reflectivity in the SNOM images revealed features that were not present in the corresponding shear-force (topology) images, and which were due to localized changes in the bulk properties of the sample. The size of the smallest detected features clearly demonstrated that near-field conditions were reached: an optical spatial resolution well below the diffraction limit was observed.

Surface differential reflectivity and surface sensitive electron spectroscopies have been applied to study the optical properties of CdTe(110) surface. The comparison of the results acquired for the surfaces prepared by two different methods (cleavage and Ar + ion sputtering) enabled us to propose a model explaining the experimental results in a coherent way.

The electronic properties of clean Si(110)16 × 2 and Si(110)2 × 3-Sb surfaces have been studied by angle resolved ultraviolet photoelectron spectroscopy (ARUPS) and surface differential reflectivity (SDR). For the clean 16 × 2 surface four surface states have been recognized by ARUPS and their dispersions have been mapped along the main symmetry lines in the surface Brillouin zone. SDR experiments revealed transitions between filled and empty surface states at ∼ 1.8, 2.4 and 2.9 eV. Antimony has been subsequently evaporated (about one monolayer) thus obtaining a 2 × 3 reconstruction. The surface electronic structure resulted to be strongly modified with three surface state bands observed in ARUPS along the [ 1 11] direction and no optical transitions detected by SDR in our energy range (1.3–3.5 eV).

In this work we present a characterization by Auger electron spectroscopy (AES) and scanning electron microscopy (SEM) of diamond surfaces, prepared with the technique of chemical vapour deposition (CVD). The initial nucleation of diamond has been studied on Si(111) substrates exposed to hydrocarbons for 5 and 20 min. The lineshape of carbon Auger transition together with SEM observation seem to show evidence of the presence of diamond nuclei on the sample after 5 min of growth and a continuous film on the sample after 20 min without any other carbon phase (noncrystalline or highly disordered carbon phase).

Si(111) and Si(100) surfaces have been observed by an air-operating scanning tunneling microscope (STM). On the cleaved Si(111) surface STM topographic images show predominantly [2¯11]-oriented monatomic steps. The distribution of the width of the terraces is centered around 4 nm. Si(100) surfaces have been hydrogen-terminated by a treatment with fluoridic acid (HF). The surface appears in the topographic STM images to be quite stable and smooth with presumably no oxide.