• Journal of Powder Materials
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• v.6 no.1
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• pp.18-35
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• 1999

Phase equilibria in the system Si3N4-TiC-TiCxN1-x-C-N were determined by thermodynamic calculations (CALPHAD-method). The reaction peaction paths for Si3N4-TiC and SiC-TiC composites in the Ti-Si-C-n system were simulated at I bar N2-pressure and varying terpreatures. At a temperature of 1923 K two tie-triangles (TiC0.34N0.66+SiC+C and TiC0.13N0.87+SiC+Si3N4) and two 2-phase fieds (TiCxN1-x+SiC; 0.13

• Korean Journal of Crystallography
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• v.8 no.2
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• pp.154-159
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• 1997

Hydorthemal coating technique has been sucessfully applied to improve oxidation resistance of graphite by forming rutile-TiO2 layer. Hydrothermal treatment of graphite in 0.2M TiCl4 aquous solution at 35℃ resulted in improved water wettability due to the formation of surface-modifying TiO2. The amount of TiO2 increased with temperature. In the presence of surface TiO2 layer, weight loss was reduced by 30%, while the initiation temperature of oxidation was lowered by 30℃.

• Journal of Magnetics
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• v.10 no.1
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• pp.1-4
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• 2005

We investigated the electronic structures and the magnetic properties of Ti-based intermetallic system of CoTi/FeTi/CoTi(110) surface and interface by using the all-electron full potential linearized augmented plane wave (FLAPW) method within the generalized gradient approximation (GGA). The calculated magnetic moments of interface Co and Fe atoms are 0.65 and 0.15 μ/sub B/, respectively. Surface and interface magnetism of CoTi/FeTi/CoTi(110) are discussed using the calculated density of states (DOS) and the spin densities.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.2
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• pp.97-101
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• 2003

New Pt/Ti and hi/Ti double-metal structures have been investigated for the application of a diffusion barrier between Cu and Si in deep submicron integrated circuits. Pt/Ti and Ni/Ti were deposited using E-beam evaporator at room temperature. The performance of Pt/Ti and Ni/Ti structures as diffusion barrier against Cu diffusion was examined by charge pumping method, gate leakage current, junction leakage current, and SIMS(secondary ion mass spectroscopy). These evaluation indicated that Pt/Ti(200${\AA}$/100${\AA}$) film is a good barrier against Cu diffusion up to 450$^{\circ}C$.

• Journal of the Korean institute of surface engineering
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• v.29 no.5
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• pp.350-356
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• 1996

This paper presents VHF-Plasma Enhanced Chemical Vapor Deposition (VHF-PECVD) of Ti/TiN with silne reduction process, using $TiCl_4$ source. VHF plasma, which is denser than a conventional RF plasma, produces a large number of radicals. Silane reduction process, which supplies silane radicals, more promotes dissociation of Ti-Cl bond than a conventional hydrogen reduction process. therefore, the VHF-PECVD with silane reduction process forms high quality Ti/TiN films, which have low level of Cl content(<0.2 at.%). In result, the resistivity for Ti or TiN is less than 200$\mu$$\Omega$cm. The surface morphology of Ti film is very smooth. The structure of TiN film is amorphous. Furthermore, excellent step coverage for the films is obtained.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2001.06a
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• pp.66-67
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• 2001

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2001.11a
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• pp.42-42
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• 2001

• Korean Journal of Materials Research
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• v.11 no.7
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• pp.580-584
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• 2001

We have investigated the deposition characteristics of Ti-Si-N films obtained by rf magnetron sputtering with ratios of Ti/Si targets in an $Ar/N_2$ gas mixture. The growth rate and stoichiometry dependence of the Ti-Si-N films on the ratio of Ti/Si and $N_2$ flow rate ratio were found to be due to the different nitriding rate of Ti and Si targets. Additionally, their different sputtering yield of nitrified Ti and Si make a reason as well. Lowering Si content in the film favored the formation of crystalline TiN, leading to the low resistivity. Increasing N content led to the Ti-Si-N films having a higher density and compressive stress, suggesting that the N content in the film is one of the most important factors determining the diffusion barrier characteristics. In the current work, the optimum process conditions for the formation of efficient diffusion barrier of Ti-Si-N film has successfully obtained by manipulating the Ti/Si ratio of target and $N_2$ flow rate ratio.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.11 no.1
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• pp.20-26
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• 2001

Titanium boride ($\textrn{TiB}_{x}$) films were deposited on (100) silicon substrates at the substrate temperature of $500^{\circ}C$ by means of the co-evaporation of titanium and boron evaporants during deposition. The co-evaporation method makes it possible to deposit the non-stoichiometric films with different boron-to-titanium ratio($0{\le}B/Ti \le 2.5$). The resistivity increases linearly as the boron-to-titanium ratio in the as-deposited films is increased. The surface roughness of $\textrn{TiB}_{x}$ films is changed as a function of the boron-to-titanium ratio. The XRD spectrum for pure titanium film shows a highly (002) preferred orientation. For B/Ti=0.59 ratio only a single TiB phase that shows a (111) preferred orientation is observed. However, the $\textrn{TiB}_{x}$ phase with the hexagonal structure of the $AlB_2$(C32) type appears as the boron concentration increase, and only a single $\textrn{TiB}_{x}$ phase is observed for $B/Ti \ge 2.0$ ratio. The $\textrn{TiB}_{x}$/Si samples reveal a tensile stress (3~$20{\times}^9$dyn/$\textrm{cm}^2$) in the overall composition of the films, although the magnitude of the residual stresses is depended on the nominal B/Ti ratio.

• Journal of the Korean Chemical Society
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• v.38 no.4
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• pp.309-318
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• 1994

The stable defect structure and the single phase region of La$_2O_3$-modified BaTi$O_3$ have been studied by X-ray diffractometer and scanning electron microscope. The stable defect structure of La$_2O_3$-modified BaTi$O_3$ has been identified as [($Ba^x_{Ba})_{1-2x}(La{\cdot}_{Ba})_{2x}][Ti^x_{Ti})_{1-x/2}(V""_{Ti})_{x/2}]O_3$ which consists of La$^{3+}$ ion substitution for Ba$^{3+}$ ion in the lattice structure and the formation of Ti vacancies for the charge compensation. When 3 mol% of La$_2O_3{\cdot}3/2TiO_3$ was added to BaTi$O_3$, the unit cell structure was transformed from tetragonal to cubic and the solubility limit was about 14 mol%. When La$_2O_3{\cdot}3/2TiO_2$ was added above this solubility limit, the second phase, La$_4Ba_2Ti_5O_{18}$, was formed. In the La$_2O_3$-modified BaTi$O_3$, it was found by the liquid phase sintering process that the sinterability was decreased by excess BaO but increased by excess Ti$O_2$.