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NiSi displays the rare occurrence of contracting during heating along the axis with the smallest unit cell dimension. Because of stress due to the thermal mismatch between the film and the Si substrate, the unit cell dimensions reported in the Joint Committee on Powder Diffraction Standards record for NiSi are faulty. They seem to be reproducible in thin films prepared by reactive diffusion, but do not correspond to relaxed equilibrium conditions. For PtSi (isostructural with NiSi), there is neither expansion nor contraction along the axis with the small dimension during heating. In the present PtSi film, x-ray diffraction does not reveal any presence of residual thermal stresses at low temperature. [ABSTRACT FROM AUTHOR]

The formation of C54 TiSi[sub 2] using Ti-no alloys deposited on polycrystalline Si substrates was studied by means of in situ x-ray diffraction and resistance measurements during temperature ramping. Alloys with Nb contents ranging from 0 to 13.6 at.% were used. The formation temperature of C54 TiSi[sub 2] was reduced in the presence of Nb. However, the addition of Nb in Ti did not cause fundamental changes in the evolution of resistance versus temperature. This latter observation suggests that the mechanism for the formation of C54 TiSi[sub 2] remained the same in spite of the enhancement effect. For alloys with up to 8 at. % of Nb, the C49 TiSi[sub 2] phase formed first, as with pure Ti. When annealing the alloy with 13.6 at. % Nb, neither C49 TiSi[sub 2] nor C54 were found in the usual temperature ranges, instead, C40 (Nb,Ti)Si[sub 2] was observed. This phase transformed to C54 (Nb,Ti)Si[sub 2] above 950 °C. The apparent activation energy associated with the formation of C54 TiSi[sub 2] was obtained by annealing the samples at four different ramp rates from 3 to 27 K/s; it decreased continuously from 3.8 to 2.5 eV with increasing Nb content from 0 to 8 at. %. The apparent activation energy for the formation of C40 (Nb,Ti)Si[sub 2] was found to be 2.6 eV. The possible physical meaning, or lack thereof, of the high activation energies derived from experimental measurements is extensively discussed. A qualitative model is proposed whereby nucleation would be rate controlling in pure TiSi[sub 2], and interface motion in samples with 8 at. % Nb. [ABSTRACT FROM AUTHOR]

Presents a study that investigated the formation of nickel (Ni)-silicon (Si) with platinum (Pt)-Si using Rutherford backscattering, x-ray diffraction, resistance measurements and optical and electronic microscopy. Description of the PtSi structure; Effects of nucleation on the formation of nuclei at the interfaces NiSi or PtSi.

Presents a study which examined the resistivity of the solid solutions of cobalt silicon[sub2] and nickel silicon[sub2] that was prepared from the solid-state reaction of thin films of nickel-cobalt allows with their silicon substrates. Experimental procedures; Results; Discussion.

Discusses the correlation between chemistry and the amount of mixing in bilayers submitted to ion bombardment. Importance of thermodynamic forces in interfacial mixing during ion bombardment; Information on the chemical aspects of the interactions; Correlation between electronegativity differences and the mixing effects.

Provides information on a study which used the Kissinger plots to analyze in situ resistance monitoring of silicide thin film reactions during heating at a constant rate. Kinetics of silicide formation; Activation energy for diffusion; Validity of the Kissinger method.

Presents a study which determined the dominant diffusion species in the formation of Al[sub2]Cu, Mg[sub2]Cu] and Mg[sub2]Ni. Experimental details; Results and discussion; Conclusion.

Investigates the structure of zirconium silicide thin films by high-resolution electron microscopy. Significance of silicides in electronic technology; Possible faults in the basic C49 structure; Preparation of the samples by the successive depositions of two layers of silicon and zirconium.

Presents information on a study which described attempts to decrease transformation temperature of titanium silicate by low-energy ion bombardment at elevated temperature. Methods; Results; Discussion.

Presents a study that analyzed the process of atomic transport in the silicide during oxidation of silicide layers formed on Silicon substrates by means of implanted inert markers. Diffusion of Cr atoms toward the silicon substrates; Thermodynamic conditions during oxidation; Details of the results of the study.

Details a study which analyzed the mechanism of atomic transport inside the silicide during thermal oxidation of silicide layers on silicon substrates by means of inert gas markers. Marker displacement and marker position; Impact of oxidation on the amount of silicon between the marker and the free surface; Process of silicide oxidation.

Studies the use of heat treatment in the removal of fluorine from a polycrystalline silicon gate structure in a chemical vapor deposition system. Details on the experiment; Results of the study; Conclusions.

Focuses on a study which investigated the isotope separation and growth mechanisms of nickel silicides by secondary ion mass spectrometry. Formations of Ni[sub2]Si and nickel silicide; Experimental techniques and results; Discussion and conclusions.

Focuses on a study which compared the mobilities of metal and silicon atoms in disilicides of chromium-molybdenum and chromium-tungsten on silicon substrates. Experimental procedures; Results; Conclusion.

Presents a quantitative study of oxygen behavior during the formation of chromium disilicide and titanium disilicide. Extent of the silicide formation monitored by backscattering spectrometry; Mass and energy dispersive recoil spectrometry; Oxygen depth profile from resonant scattering for a chromium samples.

Examines the diffusion of elements implanted in films of cobalt disilicide. Experimental procedures; Profiles of the diffusing elements; Conclusions.

Presents a study which analyzed the diffusion of the implanted atoms of gallium, germanium and antimony into thick layers of TiSi[sub2] prepared by metal-silicon reaction. Experimental techniques used; Information about the microstructure of the atoms; Modifications of the implant distributions by annealing; Effect of a Ti implant on the modification of the dopant distribution.

Presents a study that applied in situ ellipsometry to investigate the oxidation behavior of a group of silicides on single-crystal silicon substrates. Background on metal silicides; Assessment of the oxidation rates of the silicides; Analysis of the effect of the electronic properties of the silicides.

Presents a study which examined the preparation of tantalum silicon[sub 2]-tungsten silicon[sub 2] alloys from the reaction of silicon with tantalum-tungsten films to explore the constitutional diagram of the tantalum silicon[sub 2]-tungsten silicon[sub 2] pseudobinary system. Experimental procedures and results; Discusion; Conclusion.

Analyzes the diffusivities of boron (B), phosphorus (P) and arsenic (As) implanted in TiSi[sub2], using secondary ion mass spectroscopy. Details of the lattice diffusion coefficients for As and P; Comparison between the dopant diffusion in silicides and silicon; Description of the TiSi[sub2] layers; Cause of the profile change observed for B after annealing.

Part I. Presents a study that investigated the pseudobinary system titanium-silicon (Si)[sub2]-tungsten (W)-Si[sub2]. Contents of the equilibrium phase diagram; Phases of WSi[sub2]-rich alloys; Resistivity of the different alloys.

Focuses on a study which investigated titanium interaction with phosphorus-doped polycrystalline silicon gate electrodes. Purposes of polysilicon doping; Limitations on phosphorus doping in the polysilicon for TiSi[sub2] formation; Resistance of the polysilicon-metal silicide films.

Presents a study on interdiffusion and phase formation in films of Sn/Cu and Cu/Sn, with emphasis on the effect of heat treatments. Experimental procedure used to carry out the study; Results of the study; Comparison with resistivity data of previous Cu(Sn) film studies; Statistical data supporting the results.

Presents a mathematical model of oxidation of SixGe1-x alloys. Simulation of the growth of silicon dioxide; Determination of silicon distribution in SixGe1-x using numerical methods; Assumption of simultaneous oxidation of germanium and silicon; Growth of a mixed oxide; Comparison between simulation and experiment for wet oxidation in pyrogenic steam of polycrystalline SixGGe1-x films.

Examines the oxidation of polycrystalline SixGe1-x films with different compositions in pyrogenic steam for various lengths of time. Enhancement of oxidation by the presence of germanium; Rejection of germanium; Piling up of germanium at the interface between the growing SiO2 and the remaining SixGe1-x; Interdiffusion of silicon and germanium.