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Nitrided HfO 2 films are deposited by direct liquid injection chemical vapor deposition ͑CVD͒ using O 2 or N 2 O as oxidants. Deposition kinetics, phase, chemical composition, bonding, and dielectric properties of the films obtained from the two different oxidants are compared. Depositions in nitrous oxide display an activation energy ͑9.9 kcal/mol͒ less than that observed with oxygen ͑13.6 kcal͒. Films obtained from nitrous oxide are amorphous as determined by grazing incidence X-ray diffraction, while films deposited using oxygen are mixtures of amorphous and crystalline phases. Films deposited from nitrous oxide have lower bulk and interface ͑with silicon͒ nitrogen concentrations relative to films deposited in oxygen. The amorphous structure of nitrous oxide deposited films and an enhanced concentration of oxygen atoms from nitrous oxide are believed to be the reasons for the reduced interface nitrogen concentrations. Capacitance-voltage measurements demonstrate that films deposited with nitrous oxide have lower dielectric constants and lower interface trap densities relative to films deposited from oxygen. Leakage currents of the films deposited in nitrous oxide are smaller than those of films deposited in oxygen. Nitrogen concentration and oxygen content at the film/silicon substrate interface appear to be the reason for the distinct electrical properties of films deposited using the two oxidants.As the minimum feature size in complementary metal-oxidesemiconductor ͑CMOS͒ devices approaches 60 nm, 1 the gate dielectric thickness will fall below 1.5 nm. For the current gate material SiO 2 , the leakage current of a film Ͻ1.5 nm will increase sufficiently to impair device operation. Thus, high-dielectric-constant ͑high-k͒ materials are being investigated as replacements for SiO 2 in CMOS devices in order to reduce this leakage. Because the dielectric constants of high-k materials ͑usually Ͼ 10͒ are larger than that of SiO 2 ͑ = 3.9͒, the high-k gate layer can be physically thicker than a capacitively equivalent SiO 2 gate layer ͑t high-k / high-k = t SiO 2 / SiO 2 ͒; as a result, the leakage current is reduced. Recently, a number of binary and ternary metal oxides have been studied as candidates for new gate dielectrics, including Al 2 O 3 , 2 ZrO 2 , 3 HfO 2 , 4-6 and ͑Zr, Sn, Ti͒O 2 . 7,8 Because of its high dielectric constant ͑15-25͒, large bandgap ͑5.68 eV͒, and thermal stability with silicon, attention has focused on HfO 2 -based high-k materials. 4-6 In order to improve the thermal stability and resistance to oxygen and dopant diffusion, nitrogen atoms are sometimes introduced into HfO 2 films. Nitrided HfO 2 films have been obtained by ammonia annealing of deposited HfO 2 films 9 by the use of amide precursors ͑e.g., Hf͓N͑CH 3 ͒ 2 ͔ 4 and Hf͓N͑C 2 H 5 ͒ 2 ͔ 4 ͒, 10-14 or by incorporation of nitrogen-containing reactants such as NH 3 into chemical vapor deposition ͑CVD͒ processes. 15 In order to optimize the electrical properties of HfO 2 -based dielectrics, variations in the CVD process have been studi...

The microstructure evolution in pure copper deformed by rolling at liquid nitrogen temperature was determined by using X-ray diffraction peak profile analysis. The crystallite size distribution and defects evolution were determined as a function of different reduction levels ͑e.g., 67%, 74%, 87%, and 97%͒. By using the Multiple Whole-Profile fitting procedure the Fourier transforms of the experimental X-ray peak profiles were fitted all at once by theoretical calculated functions. Here it is assumed that the crystallites are spherical shape and have a log-normal size distribution. It is also supposed that the strain broadening of the profiles is caused by ͗110͘ ͕111͖-type dislocations. The results show that the median and the variance of the crystallite size distribution decreases as the deformation reduction increases. The dislocation density has a minimum value at 74% reduction. The increase of the dislocation density at higher deformation levels is due to the nucleation of new generation of dislocations from the crystallite grain boundaries. It was found that the edge dislocation type dominate, the dislocation network formed during the deformation process. © 2005 International Centre for Diffraction Data.

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