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Iron silicide thin films (∈-FeSi, α-FeSi 2 and β-FeSi 2 ) were grown on silicon (111) substrates using the metalorganic vapour phase epitaxy (MOVPE) process with iron pentacarbonyl (Fe(CO) 5 ) and disilane (Si 2 H 6 ) precursors. Attention was mainly paid to the β-FeSi 2 phase. Transmission electron microscopy (TEM) and X-ray diffraction measurements allowed optimization of the growth process and revealed the nature and structure of the layers grown on the silicon substrate. A growth model is discussed and the action of the thermal annealing, which leads to the coalescence of the dendrites to form a continuous film of β-FeSi 2 up to about 1000 A thick, is described. Finally a photoluminescence signal has been detected in the range of the expected direct band gap value of β-FeSi 2 .

Using the capacitance‐voltage technique and mainly deep‐level transient spectroscopy (DLTS), we studied silicon‐silicon epitaxial layer structures grown by the limited reaction process using silane diluted in hydrogen. We develop a simple but original model to interpret the DLTS data. The use of the two techniques allows the determination of the physical parameters of the structure, i.e., the doping level, the thickness of the layers, and the density and capture cross section of the states localized at the different interfaces of the structure.

Summary form only given. When growing epitaxial heterostructures involving both arsenic and phosphorus based III-V semiconductors (for instance GaInAs/InP or GaAs/GaInP), the most common recipe used to reduce anion intermixing is to perform a growth interruption during which the GaInAs or GaAs surface is exposed to phosphorus before the growth of InP or GaInP. This kind of procedure then raises the question of the reactivity of an arsenide surface to a phosphorus flux in order to optimize the growth interruption. However, if some results do exist related to the behavior of a GaAs surface exposed to phosphorus, very few are reported on the reactivity of the InAs surface. In this context, we have studied the surface reactivity of Ga/sub 1-x/In/sub x/As alloys to a phosphorus flux. Samples are grown by gas source molecular beam epitaxy (GSMBE). Surface reconstruction and morphology are followed 'in-situ' by reflection high energy electron diffraction (RHEED) and 'ex-situ' by atomic force microscopy (AFM). The surface chemistry of some samples has been determined by X-ray photoelectron spectroscopy (XPS) in a vacuum chamber connected under UHV to the growth chamber.

We present a detailed investigation of the interface formation in the TiSi system at low temperatures (25–300°C). Accurate Auger and Electron Energy Loss measurements and analysis are used to study the microscopic properties of the interfaces. The correlation between these properties and in situ resistivity measurements is discussed.