TaCN layers were deposited using metal-organic chemical-vapor deposition for applications as metal gate electrodes in p-type metal-oxide-semiconductor (pMOS) devices. The films were formed by thermal decomposition of tertiary-amylimido-tris(dimethylamido)tantalum (TAIMATA®) between 400 and 600 °C. The composition was dependent on the growth temperature with increasing C and decreasing N content at higher temperature. Films grown below 500 °C were nearly amorphous and became weakly polycrystalline with a cubic structure at higher growth temperature. The layer density was ∼8.1 g/cm3, about half of the TaCN bulk density. Grazing-incidence x-ray diffraction and transmission electron microscopy showed that the films consist of small polycrystalline grains in an amorphous matrix. The resistivity was found to decrease with increasing growth temperature. Lowest resistivity values were around 1 mΩ cm for films grown at 600 °C. The films formed an ∼4 nm thick insulating surface oxide, which leads to a thickness dependence of the film resistivity. Oxygen was also found to diffuse slowly into the bulk metal, which leads to a resistivity aging effect. The effective work function of the TaCN films was found to be 4.8 eV on HfSiO4 and HfSiON and to shift weakly by high thermal budget annealing toward the Si valence band, reaching 4.9 eV on HfSiO4.

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Direct catalytic hydrothermal conversion of cellulose to C 3 + C 4 hydrocarbons at a low temperature (443 K) over a Pt/zeolite catalyst without hydrogen or other expensive reagents was investigated. Pt supported on NH 4 + -form ultra-stable Y-type (NH 4 -USY) zeolite catalyst, which showed the highest activity among the tested Pt/zeolite catalysts, has appropriate acidity and a suitable active Pt site. The C 3 + C 4 hydrocarbon yield reached 14.5 C-% during the reaction over the Pt/NH 4 -USY catalyst at 443 K after 72 h of the reaction. Results showed that the acid strength of the zeolite support was an important factor affecting the cellulose decomposition activity. Because of their structural sensitivity, Pt/zeolite catalysts with Pt particles larger than 5 nm, including Pt/NH 4 -USY catalyst, showed higher TOF values than catalysts with Pt particles smaller than 5 nm.

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