Amorphous carbon nitride films (a-CNx) were deposited on silicon tip arrays by rf magnetron sputtering in pure nitrogen atmosphere. The field emission property of carbon nitride films on Si tips was compared with that of carbon nitride on silicon wafer. The results show that field emission property of carbon nitride films deposited on silicon tips can be improved significantly in contrast with that on wafer. It can be explained that field emission is sensitive to the local curvature and geometry, thus silicon tips can effectively promote field emission property of a-CNx films. In addition, the films deposited on silicon tips have a smaller effective work function ( F = 0.024 eV)of electron field emission than that on silicon wafer ( F = 0.060 e V), which indicates a significant enhancement of the ability of electron field emission from a-CNx films.

The chemical bonding states and the structure of CNx films grown on Si(001) substrate by using RF magnetron sputtering were studied at different substrate bias voltages(V-b). The incident ions energy bombarding the substrate surface could be controlled by the substrate negative bias, which would influence the chemical bonding states of CNx films. The results of Raman, FTIR and XPS showed that the nitrogen atoms were bound to sp, sp(2) and sp(3) hybridized carbon atoms. The content of sp(3) C-N increased firstly with the increase of Vb, reached to the maximum value at V-b = -50 V, and then decreased continually. This trend indicated the content of sp(3) C-N bonds in the CNx films were closely related to change of ions energy.

The carbon nitride films deposited by r.f. magnetron sputtering in pure N2 discharge were annealed in vacuum up to 900 ℃. The chemical composition and bonding structure of the films were studied using x-ray photoelectron spectroscopy, Fourier Transform Infrared. The effects of thermal annealing on the bonding structure and the electron field emission characteristics of CNx films wer e investigated. It is found that the sp2 bonds and N content in CNx films are closely related to the filed emission of CNx films. The results show that thermal annealing treatment causes a great loss of N content and a larger formation of sp2 bonds in CNx films, which would influence sign ificantly the field emission properties for the CNx films. The CNx films annealed at 750 ℃ show the optimal electron emission properties. Besides, the correlation between the chemical bonding structures and electron emission properties for the CNx films was also discussed.

The carbon nitride films deposited by rf magnetron sputtering in a pure N2 discharge were annealed in vacuum up to 900 °C. The chemical composition and bonding structure of the films were studied using x-ray photoelectron spectroscopy, Raman spectroscopy, and Fourier transform infrared spectroscopy. It was found that the nitrogen atoms were bound to sp, sp2, and sp3 hybridized carbon atoms in as-deposited films. The effects of the thermal annealing on bonding structure and the electron field emission characteristics of CNx films were investigated. The results showed that thermal annealing treatment caused a great loss of N content and favor formation of sp2 bonds in CNx films, which would significantly influence the field emission properties for the CNx films. The CNx films annealed at temperature of 750 °C showed the optimal electron emission properties. Besides, the correlation between the chemical bonding structures and electron emission properties for the CNx films was discussed.

Amorphous carbon nitride films deposited by rf magnetron sputtering were annealed up to 900°C in vacuum for 1 h. The variations of composition and bonding structure of the films were investigated by Fourier transformation infrared, Raman spectroscopy and x-ray photoelectron spectroscopy. The results showed that a great loss of N content was induced by annealing in the films surface, which dropped abruptly from 26.4 to l.5 at.% with annealing temperature rising to 900°C. In addition, it was found that annealing led to disruptions of most C–N bonds and the conversion from sp3 C to sp2 C. As a result, graphitization occurred and a large fraction of sp2 C bonds was formed in the CNx films surface. Surface etching of post-annealed films was carried out to study the change in the film interior layer. Approximately 7 at.% nitrogen atoms were found to still remain in the film interior layer at the annealing temperature 900°C. These remaining N atoms were mainly bound to sp3 C in CNx films instead of N–sp2 C bonds, which indicates the N–sp3 C bonds have higher thermal stability than N–sp2 C bonds.

Magnetron sputtered amorphous carbon nitride films were annealed at different temperatures (450–900°C) and time (30–120min). Compositional, bonding structural and surface morphological modifications of the films were characterized by Fourier transformation infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and atomic force microscopy. The as-deposited film was found to have nitrogen content of 30at%, and the carbon atoms were bonded to nitrogen atoms in the chemical structure state of CN, CN and CN bonds. The FTIR and XPS results showed that the films were thermally stable without an obvious change in the films as annealing temperature was lower than 600°C. The relative intensity ratio of CN over CN bonds reached a maximum at annealing temperature of 750°C, and then decreased gradually at annealing temperature up to 900°C. The CN bonds in the films decreased with the increase of annealing temperature and eliminated completely at annealing temperature of 900°C. These results revealed that annealing caused a substantial decrease in the number of weak bonds between carbon and nitride atoms. The CN bonds have higher thermal stability than CN bonds and CN bonds in the films. Simultaneously annealing also led to the formation of a large fraction graphitic-like carbon in the films while nitrogen escaped from the film. Besides, the surface roughness of the films increased with annealing temperature. However, when annealing time was increased from 30 to 120min at annealing temperature of 750°C, only a slight effect of the annealing time on composition, bonding structure and the surface roughness of the films was observed.

The small angle X-ray scattering (SAXS) technique has been used to characterize the coarsening kinetics of the δ′ phase in 1420 Al–Li alloy aged at 160°C for several times. The results showed that the deviation of δ′ phase coarsening from the LSW coarsening rate law exists between the early stage and later stage of aging. It maybe identified by the mechanism of spinodal decomposition of the δ′ phase.