Low Temperature Tungsten, Tungsten Carbide and Tantalum Carbide Film Growth

2000 ◽  
Vol 648 ◽  
Author(s):  
Y.-M. Sun ◽  
S.Y. Lee ◽  
E. R. Engbrecht ◽  
K. Pfeifer ◽  
S. Smith ◽  
...  

Abstract:Low temperature chemical vapor deposition of tungsten, tungsten carbide and tantalum carbide films on SiO2/Si(100) surfaces was studied by X-ray photoelectron spectroscopy (XPS) and electron microscopy. Tungsten carbide films were deposited using the W(CO)6precursor with and without ethylene over temperatures ranging from 250 to 500 °C. The films grown without ethylene contained approximately 13 % carbon and 6 % oxygen. Cross section scanning electron microscopy imaging of the films grown at various temperatures without ethylene shows a polycrystalline microstructure, and the grain size increases dramatically as the growth temperature increases. Introducing ethylene increased carbon incorporation and changed the microstructure to amorphous-like. The tungsten to carbon ratio was approximately 2 at growth below 500 °C, and reached ~ 1.2 above 500 °C. The tantalum carbide films were deposited in a plasma enhanced chemical vapor deposition (PECVD) process using methane. The PECVD tantalum carbide films were conductive with a resistivity of ~1000 µΩ cm, which is about one order of magnitude lower than thermally grown films from pentakisdimethylamino tantalum.

2007 ◽  
Vol 989 ◽  
Author(s):  
Xiao Liu ◽  
Thomas H Metcalf ◽  
Qi Wang ◽  
Douglas M Photiadis

AbstractWe have measured the internal friction (Q-1) of amorphous silicon nitride (a-Si3Nx) films prepared by a variety of methods, including low-pressure chemical-vapor deposition (LPCVD), plasma-enhanced chemical-vapor deposition (PECVD), and hot-wire chemical-vapor deposition (HWCVD) from 0.5 K to room temperature. The measurements are made by depositing the films onto extremely high-Q silicon double paddle oscillator substrates with a resonant frequency of ~5500 Hz. We find the elastic properties of these a-Si3N4 films resemble those of amorphous silicon (a-Si), demonstrating considerable variation, depending on the film growth methods and post deposition annealing. The internal friction for most of the films shows a broad temperature-independent plateau below 30 K, characteristic of amorphous solids. The values of Q-1, however, vary from film to film in this plateau region by more than one order of magnitude. This is typical for tetrehedrally bonded amorphous thin films, like a-Si, a-Ge, and a-C. The PECVD films have the highest Q-1 just like an ordinary amorphous solid, while LPCVD films have an internal friction more than one order of magnitude lower. All the films show a reduction of Q-1 after annealing at 800°C, even for the LPCVD films which were prepared at 850°C. This can be viewed as a reduction of structural disorder.


2003 ◽  
Vol 775 ◽  
Author(s):  
Joel De Jesùs ◽  
Juan A. Gonzàlez ◽  
Oscar O. Ortiz ◽  
Brad R. Weiner ◽  
Gerardo Morell

AbstractThe transformations induced by the application of a continuous bias voltage parallel to the growing surface during the sulfur-assisted hot-filament chemical vapor deposition (HFCVD) of nanocrystalline diamond (n-D) films were investigated by Raman spectroscopy (RS), scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The films were deposited on molybdenum substrates using CH4, H2 and H2S. Bias voltages in the range of 0 – 800 VDC were applied parallel to the substrate surface continuously during deposition. The study revealed a significant improvement in the films' density and a lowering in the defect density of the nanocrystalline diamond structure for parallel bias (PB) voltages above 400V. These high PB conditions cause the preferential removal of electrons from the gaseous environment, thus leading to the net accumulation of positive species in the volume above the growing film, which enhances the secondary nucleation. The nanoscale carbon nuclei self-assemble into carbon nano-clusters with diameters in the range of tens of nanometers, which contain diamond (sp3-bonded C) in their cores and graphitic (sp2-bonded C) enclosures. Hence, the observed improvement in film density and in atomic arrangement appears to be connected to the enhanced presence of positively charged ionic species, consistent with models which propose that positively charged carbon species are the crucial precursors for CVD diamond film growth.


2004 ◽  
Vol 19 (3) ◽  
pp. 697-706 ◽  
Author(s):  
Anna W. Topol ◽  
Kathleen A. Dunn ◽  
Karl W. Barth ◽  
Guillermo M. Nuesca ◽  
Brian K. Taylor ◽  
...  

Results are presented from a systematic investigation to design and optimize a low-pressure chemical vapor deposition (CVD) process for manganese-doped zinc sulfide (ZnS:Mn) thin films for electroluminescent (EL) device applications. The CVD process used diethylzinc (DEZ), di-π-cyclopentadienyl manganese (CPMn), and hydrogen sulfide (H2S) as co-reactants and hydrogen (H2) as carrier gas. A design of experiments approach was used to derive functionality curves for the dependence of ZnS:Mn film properties on substrate temperature and flow rates (partial pressures) of DEZ, CPMn, H2S, and H2. Film physical, chemical, structural, and optical properties were examined using Rutherford backscattering spectrometry, dynamic secondary ion mass spectroscopy, x-ray photoelectron spectroscopy, nuclear-reaction analysis, x-ray diffraction, transmission electron microscopy, atomic force microscopy, and scanning electron microscopy. EL measurements were carried out on ZnS:Mn-based dielectric–sulfur–dielectric stacks incorporated into alternating-current thin-film electroluminescent devices. An optimized process window was established for the formation of films with predominantly (0 0 2) orientation, grain size larger than 0.2 μm, and Mn dopant level approximately 0.5 at.%. A brightness of 407 cd/m2 (119 fL) and efficiency of 1.6 lm/W were obtained, as measured at 40 V above threshold voltage and 60 Hz frequency.


2021 ◽  
Vol 12 ◽  
pp. 1365-1371
Author(s):  
Vladislav Dřínek ◽  
Stanislav Tiagulskyi ◽  
Roman Yatskiv ◽  
Jan Grym ◽  
Radek Fajgar ◽  
...  

Chemical vapor deposition was applied to synthetize nanostructured deposits containing several sorts of nanoobjects (i.e., nanoballs, irregular particles, and nanowires). Analytical techniques, that is, high-resolution transmission electron microscopy, scanning electron microscopy, electron dispersive X-ray analysis, selected area electron diffraction, and X-ray photoelectron spectroscopy, showed that unlike nanoballs and particles composed of crystalline germanium, the layer was made of chromium germanide CrGex. The nanowires possessed a complex structure, namely a thin crystalline germanium core and amorphous CrGex coating. The composition of the nanowire coating was [Cr]/[Ge] = 1:(6–7). The resistance of the nanowire–deposit system was estimated to be 2.7 kΩ·cm using an unique vacuum contacting system.


2013 ◽  
Vol 31 (1) ◽  
pp. 01A105 ◽  
Author(s):  
Gilbère J. A. Mannie ◽  
Gijsbert Gerritsen ◽  
Hendrikus C. L. Abbenhuis ◽  
Joop van Deelen ◽  
J. W. (Hans) Niemantsverdriet ◽  
...  

2002 ◽  
Vol 756 ◽  
Author(s):  
Davide Barreca ◽  
Alberto Gasparotto ◽  
Eugenio Tondello ◽  
Stefano Polizzi ◽  
Alvise Benedetti ◽  
...  

ABSTRACTNanocrystalline CeO2 thin films were synthesized by Plasma-Enhanced Chemical Vapor Deposition using Ce(dpm)4 as precursor. Film growth was accomplished at 150–300°C either in Ar or in Ar-O2 plasmas on SiO2 and Si(100) with the aim of studying the effects of substrate temperature and O2 content on coating characteristics. Film microstructure as a function of the synthesis conditions was investigated by Glancing Incidence X-Ray Diffraction (GIXRD) and Transmission Electron Microscopy (TEM), while surface morphology was analyzed by Atomic Force Microscopy (AFM). Surface and in-depth chemical composition was studied by X-ray Photoelectron Spectroscopy (XPS) and Secondary Ion Mass Spectrometry (SIMS).


MRS Advances ◽  
2018 ◽  
Vol 3 (4) ◽  
pp. 191-197
Author(s):  
José E. Nocua ◽  
Gerardo Morell

ABSTRACTBoron nitride (BN) has a very high thermal conductivity and excellent thermal shock resistance. These properties make BN an important material for industrial applications involving surfaces in contact with molten metals. These applications require straightforward deposition methods that produce uniform BN coatings. Using borazine (B3N3H6) as a precursor, we deposited BN coatings on silicon substrates by cold-wall chemical vapor deposition (CVD). The microstructure, composition, and morphology of the coatings were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), and electron energy loss spectroscopy (EELS). These characterizations show that the BN coatings deposited are uniform, predominantly of hexagonal structure, and N-rich.


2002 ◽  
Vol 16 (06n07) ◽  
pp. 1091-1095 ◽  
Author(s):  
W. T. ZHENG ◽  
X. WANG ◽  
T. DING ◽  
X. T. LI ◽  
W. D. FEI ◽  
...  

The carbon nitride films were deposited on single crystalline Si(001) and polycrystalline diamond substrates using microwave plasma chemical vapor deposition (MPCVD) with CH4+N2 as well as CH4+NH3 mixtures as the reactive gas source, respectively. Different CH4/N2 and CH4/NH3 gas ratios were tested. The results showed that carbon nitride films with different nitrogen content could more readily be obtained using a mixture of CH4/N2 rather than CH4/NH3. The films grown by different CH4/N2 ratios showed different morphology, which was revealed by scanning electron microscopy (SEM). The crystalline carbon nitride films containing silicon were realized using a CH4:N2 = 1:100 ratio. X-ray photoelectron spectroscopy (XPS), Auger electron microscopy (AES), Raman spectroscopy, and X-ray diffraction were used to characterize the composition and chemical bonding of the deposited films.


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