Papers by Keyword: Tantalum Nitride

Abstract: TaN-Cu nanocomposite thin films used as materials for thin-film resistors (TFR) were prepared by magnetron pulsed dc reactive sputtering. Structural and morphological properties of films deposited on (100) Si as a function of nitrogen flow rate and substrate temperature is investigated. With the introduction of N2 gas flow indicated with different phases of nanocrystalline h-Ta, Ta2N, TaN, Ta4N5 and Cu. XRD analysis of the films deposited with increasing substrate temperature at constant flow rate of nitrogen 10 sccm indicated that the nanocrystalline with bi-phasic (fcc-TaN and fcc-Cu). The microstructure of the films was investigated by scanning electron microscopy and high-resolution transmission electron microscopy.

Abstract: The oxynitrides with composition A1-xBx(OyNz) (A: Nb and Ta, B: Al) were studied in preparation through citrate route and NH3 nitridation. In the case of Nb, the product of x = 0.5 prepared at 1000 °C was a new compound of a = 0.435 nm with rock salt structure. In this structure, Al and Nb atoms were distributed randomly in the cation sites. Anion sites were also randomly occupied by oxide and nitride ions with some amount of vacancy. The chemical composition was represented as Nb0.56Al0.44O0.38N0.37□0.25 from Rietveld refinement and oxygen/ nitrogen measurement. In the case of Ta, monoclinic Ta3N5 crystallized with a small amount of Ta4N5 impurity at x = 0.5. Aluminum compound was co-present as amorphous impurity.

Abstract: In this paper, we reported the preparation of nanocrystalline Ta3N5 particles by nitridation of Ta2O5 nanoparticles using NH3 as reactant gas. It was found that nanocrystalline Ta2O5 was converted into Ta3N5 completely at 700°C within 5.0 h, which was much lower than the temperature 850°C for the complete nitridation of micron-sized Ta2O5 powder. The resulting nitride was characterized by X-ray diffraction analysis (XRD) and field emission scanning electron microscopy (FE-SEM). The nitrogen contents in the prepared Ta3N5 powders were quantitatively determined with CHN elemental analyzer and thermogravimetry and differential scanning calorimetry (TG-DSC). The color of nanocrystalline Ta3N5 is in fresh red while the one of micrometer-sized Ta3N5 is in dark red.