Titanium nitride powder has been synthesized using titanium tetrachloride, ammonia and hydrogen. The influence of the reaction temperature on stoichiometry, particle size and production rate in the gas phase has been investigated. Crystalline titanium nitride powders were formed in all cases. The observed lattice parameter of the powders as a function of reaction temperature suggests that only at high reaction temperatures can a stoichiometric titanium nitride powder be formed. In the temperature range 900-1173 K the mean primary particle size varies between 100 and 200 nm, and the geometric standard deviation varies between 1.1 and 1.3 for the powders formed below a reaction temperature of 11 73 K. A significantly smaller primary particle size is observed at higher reaction temperatures. A fractal dimension analysis indicates that at low reaction temperatures the powders are not agglomerated.

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Thin films of boron nitride have been deposited in a plasma-enhanced chemical vapor deposition system, for use as a gate dielectric layer on InP. The InP substrates were pretreated by in situ HCl vapor etching prior to the film deposition. Borane-dimethylamine and ammonia were used as sources for boron and nitrogen. The depositions were carried out at low temperatures (320 °C), the samples being not directly exposed to the plasma which minimizes radiation damage to the substrates. The deposited films were characterized by ellipsometry, x-ray photoelectron spectroscopy, infrared and ultraviolet−visible spectroscopy. Metal-insulator-semiconductor structures were realized to evaluate the bulk dielectric and insulator−semiconductor interface properties. The growth rates are low (20 nm/h). X-ray photoelectron spectroscopy and infrared measurements showed that the layers are essentially boron nitride, with some boron excess (typically N/B≂0.8). The dielectric films were found to have an optical index n≂1.7, an optical band gap E0≂ 5.8 eV, a resistivity of about 1013 Ω cm and a dielectric constant of 3.5. Frequency dispersion, between 100 Hz and 1 MHz, of capacitance in accumulation did not exceed 10%. The interface state density was in the 1011–1012 cm−2 eV−1 range.

The kinetics of the growth of titanium nitride (TIN) by hot-wall atmospheric pressure chemical vapor deposition (CVD) has been studied using titanium tetrachloride (TIC14), hydrogen (H2), and nitrogen (N~) as reactants. The growth rate as a function of reactant concentration at different reaction temperatures is determined. The growth rate dependence in the TiC14 input concentration changes from a positive to a negative order behavior with increasing reactant concentration, and the observed maximum growth rate shifts to a higher TiC14 input concentration with increasing reaction temperature. For the growth rate a square root dependence in the N2 concentration is observed in all cases, and for the growth rate a positive order dependence in the H2 concentration is observed which changes from 0.5 to 1.5. A reaction model has been proposed based on isothermal Langmuir adsorption behavior with mutual displacement on titanium sites at the surface, and an indirect mutual displacement on nitrogen sites at the surface. This reaction model consists of a set of elementary gas-phase, adsorption, and surface reactions which are quasi-equilibrated, and a rate-determining step involving the reaction at the surface between an adsorbed TIC13 species on a nitrogen site, and an adsorbed NH species on a titanium site. Using this model the experimental and reported growth rate data can be understood as a function of reactant concentration within the temperature region from 1000 to 1273 K.Chemical vapor deposition (CVD) is a well-known synthesis method for producing titanium nitride (TIN) layers. 1-2~ These TiN layers are used, because of their electrical conductivity, 2-8 or structural properties such as wear and corrosion resistance. 7-9 TIN layers can be used as a diffusion barrier between metal and silicon in electronic circuits. 2-4 These layers are deposited in a cold-wall low-pressure CVD apparatus at substrate temperatures between 600 and 900 K using titanium tetrachloride (TiC14), ammonia (NH3), and hydrogen (H2) according to reaction 12-6

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