WNxfilms are deposited by reactive chemical vapor deposition at different amounts of nitrogen in gas mixtures.Experimental data demonstrate that nitrogen amount has a strong effect on microstructure, phase formation,t...WNxfilms are deposited by reactive chemical vapor deposition at different amounts of nitrogen in gas mixtures.Experimental data demonstrate that nitrogen amount has a strong effect on microstructure, phase formation,texture morphology, mechanical and optical properties of the WNxfilms. With increasing nitrogen a phase transition from a single WNxphase with low crystallinity structure to a well-mixed crystallized hexagonal WNxand face-centered-cubic W2N phases appears. Relatively smooth morphology at lower N2concentration changes to a really smooth morphology and then granular with coarse surface at higher N2concentration. The SEM observation clearly shows a columnar structure at lower N2concentration and a dense nanoplates one for higher nitrogen content. The hardness of WNxthin films mainly depends on the film microstructure. The absorbance peak position shifts to shorter wavelength continuously with increasing nitrogen amount and decreasing particle size.展开更多
Tungsten nitride(W_(x)N)thin films with good crystalline structure,high quality and relatively low resistivity were deposited by hot filament chemical vapor deposition(HFCVD)technique at different mixtures of N2 and A...Tungsten nitride(W_(x)N)thin films with good crystalline structure,high quality and relatively low resistivity were deposited by hot filament chemical vapor deposition(HFCVD)technique at different mixtures of N2 and Ar gases.Experimental data demonstrate that different N_(2) contents in gas mixture strongly affect microstructure,phase formation,texture morphology and resistivity of the W_(x)N films.According to X-ray diffraction(XRD)patterns,the growth of tungsten nitride films promotes δ-WN phase for lower N_(2) contents in gas mixture.At higher N_(2) contents,a phase transition is observed in the tungsten nitride films.Both hexagonal δ-WN and cubic β-W_(2)N phases coexist,and WN phase approximately disappears with N_(2) contents in the gas mixture increasing.Scanning electron microscope(SEM)images for deposited films at lower N_(2) contents in gas mixture indicate a definite dense columnar nanostructure.The electrical resistivity results exhibit a significant drop for the W_(x)N thin films with N_(2) contents in the mixed gas increasing.The changes in N_(2) content in gas mixture are found to be responsible for variation in the film resistivity values.Thus,the deposited tungsten nitride thin film at higher N_(2) contents in gas mixture has noncolumnar microstructure and lower resistivity,which may be used as a superior diffusion barrier.展开更多
文摘WNxfilms are deposited by reactive chemical vapor deposition at different amounts of nitrogen in gas mixtures.Experimental data demonstrate that nitrogen amount has a strong effect on microstructure, phase formation,texture morphology, mechanical and optical properties of the WNxfilms. With increasing nitrogen a phase transition from a single WNxphase with low crystallinity structure to a well-mixed crystallized hexagonal WNxand face-centered-cubic W2N phases appears. Relatively smooth morphology at lower N2concentration changes to a really smooth morphology and then granular with coarse surface at higher N2concentration. The SEM observation clearly shows a columnar structure at lower N2concentration and a dense nanoplates one for higher nitrogen content. The hardness of WNxthin films mainly depends on the film microstructure. The absorbance peak position shifts to shorter wavelength continuously with increasing nitrogen amount and decreasing particle size.
文摘Tungsten nitride(W_(x)N)thin films with good crystalline structure,high quality and relatively low resistivity were deposited by hot filament chemical vapor deposition(HFCVD)technique at different mixtures of N2 and Ar gases.Experimental data demonstrate that different N_(2) contents in gas mixture strongly affect microstructure,phase formation,texture morphology and resistivity of the W_(x)N films.According to X-ray diffraction(XRD)patterns,the growth of tungsten nitride films promotes δ-WN phase for lower N_(2) contents in gas mixture.At higher N_(2) contents,a phase transition is observed in the tungsten nitride films.Both hexagonal δ-WN and cubic β-W_(2)N phases coexist,and WN phase approximately disappears with N_(2) contents in the gas mixture increasing.Scanning electron microscope(SEM)images for deposited films at lower N_(2) contents in gas mixture indicate a definite dense columnar nanostructure.The electrical resistivity results exhibit a significant drop for the W_(x)N thin films with N_(2) contents in the mixed gas increasing.The changes in N_(2) content in gas mixture are found to be responsible for variation in the film resistivity values.Thus,the deposited tungsten nitride thin film at higher N_(2) contents in gas mixture has noncolumnar microstructure and lower resistivity,which may be used as a superior diffusion barrier.
