Molecular Precursors to Boron Nitride then Films: the Reactions of Diborane with Ammonia and with Hydrazine on Ru(0001)

1991 ◽  
Vol 250 ◽  
Author(s):  
Charles M. Truong ◽  
José A. Rodriguez ◽  
Ming Cheng Wu ◽  
D. W. Goodman
Keyword(s):  
Thin Films ◽  
Low Temperature ◽  
Boron Nitride ◽  
Mass Spectroscopy ◽  
Photoelectron Spectroscopy ◽  
Stoichiometric Ratio ◽  
X Ray ◽  
Molecular Precursors ◽  
Temperature Deposition ◽  
Boron Nitrogen

AbstractThe coadsorption and reaction of diborane with ammonia and with hydrazine on Ru(0001) have been studied using X-ray photoelectron spectroscopy (XPS) and thermal desorption mass spectroscopy (TDS). Diborane is found to decompose to atomic boron and hydrogen upon adsorption at T>200K. Multilayers of diborane and ammonia, deposited at 90K on Ru(0001), react when annealed to 600K. The XPS results indicate that boron-nitrogen adlayers can be formed by this reaction. These boron-nitrogen films are boron-rich and.decompose at temperatures higher than 1100K. Our TDS studies reveal that hydrazine decomposes extensively to NH3, N2, N and H on Ru(0001). Due to its higher reactivity, boron-nitrogen films of B/N stoichiometric ratio near unity are obtained when hydrazine is used rather than ammonia. In our studies, these films were formed by either simultaneously dosing B2H6 and N2H4 at 450K or by coadsorption of the reactants at 90K and subsequent annealing to 450K. These studies have shown that diborane and hydrazine can be successfully used as molecular precursors in the low temperature deposition of boron nitride thin-films.

Composition and Chemical Structure of Nitrided Silica Gel

1984 ◽  
Vol 32 ◽  
Author(s):  
R. K. Brow ◽  
C. G. Pantano
Keyword(s):  
Thin Films ◽  
Infrared Spectroscopy ◽  
Low Temperature ◽  
Silica Gel ◽  
Photoelectron Spectroscopy ◽  
Chemical Structure ◽  
Sol Gel ◽  
X Ray ◽  
Higher Temperature ◽  
Low Temperature Treatments

ABSTRACTSol/gel derived silica thin films were thermally treated in NH3 for four hours at temperatures up to 1300C. The films were analyzed by ellipsometry, X-ray photoelectron spectroscopy (XPS) and infrared spectroscopy (IR). Over 30 mol% nitrogen was incorporated in the film treated at 1300C. Using IR and XPS analyses, -NHx groups were found to be present after low temperature treatments, while nitrogen was incorporated in an oxynitride structure after the higher temperature treatments.

MgF2 Film Deposited by IAD with End-Hall Ion Source Using SF6 as Working Gas

2007 ◽  
Vol 364-366 ◽  
pp. 762-767 ◽  
Author(s):  
Jin Cherng Hsu ◽  
Paul W. Wang ◽  
Huang Lu Chen
Keyword(s):  
Thin Films ◽  
Photoelectron Spectroscopy ◽  
Sulfur Hexafluoride ◽  
Good Choice ◽  
Ion Source ◽  
Xps Spectra ◽  
X Ray ◽  
Temperature Deposition ◽  
Ftir Spectrometer

Traditionally, Argon (Ar) is used as a working gas to deposit MgF2 thin films in ionbeam assisted deposition (IAD) process. It improves the quality of the films, but cannot reduce the loss of F- ions during the process which also results in other impurities appearing in MgF2 thin films. The contaminants in MgF2 film such as C, O and Ar atoms are identified by X-ray photoelectron spectroscopy (XPS). In this study, sulfur hexafluoride (SF6) was chosen as a working gas in which more F– ions were created from the dissociation of SF6 in the IAD process in order to increase the content of F and eliminate the contamination. In our knowledge, very few reports have been published on IAD used SF6 as a working gas in optical coating process at around room temperature. Deposition of unwanted sulfur atoms was the concern when SF6 was used in the IAD process, however, no sulfur was observed in XPS spectra. The XPS spectra of Mg 2p, O 1s and F 1s were decomposed and analyzed with some Gaussian sub-peaks. The transmission spectra of films were measured in UV and visible ranges. The water absorption phenomena in the films were also measured by Fourier Transform Infrared (FTIR) spectrometer. Compared to the films fabricated by other methods, using SF6 as a working gas in IAD is a good choice to deposit MgF2 films.

Structural Characterization of γ-Terpinene Thin Films Using Mass Spectroscopy and X-Ray Photoelectron Spectroscopy

2015 ◽  
Vol 12 (10) ◽  
pp. 1085-1094 ◽  
Author(s):  
Jakaria Ahmad ◽  
Kateryna Bazaka ◽  
Jason D. Whittle ◽  
Andrew Michelmore ◽  
Mohan V. Jacob
Keyword(s):  
Thin Films ◽  
Mass Spectroscopy ◽  
Structural Characterization ◽  
Photoelectron Spectroscopy ◽  
X Ray

Optical and Spectroscopic Ellipsometric Study of Indium Boron Nitride Sputtered Thin Films with Low Boron Concentration

2011 ◽  
Vol 1307 ◽  
Author(s):  
Mohammad A. Ebdah ◽  
Martin E. Kordesch ◽  
David C. Ingram ◽  
Hamad AlBrithen ◽  
Abdel-Rahman A. Ibdah ◽  
...  
Keyword(s):  
Thin Films ◽  
Boron Nitride ◽  
Wavelength Range ◽  
Photoelectron Spectroscopy ◽  
Fused Silica ◽  
Amorphous Semiconductors ◽  
Optical Bandgap ◽  
Linear Extrapolation ◽  
X Ray ◽  
Absorbing Layer

ABSTRACTAmorphous indium boron nitride (a-InBN) thin films were successfully fabricated using radio frequency (RF) magnetron sputtering, and were deposited onto fused silica and c-Si(100) substrates. Sputtering was achieved using a target of polycrystalline B and In species with B/In nominal at.% ratio of 25/75 under the flow of nitrogen. The structure and composition of the films have been investigated by X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS), respectively. The XRD patterns reveal that the sputtered films are amorphous, and the XPS confirms the presence of boron in the films in addition to an oxide overlayer. The optical absorption of samples grown on silica was obtained using spectrophotometry (SP) technique in the wavelength range (200 - 800) nm. Analysis of the absorption coefficients using the Tauc linear extrapolation gives an optical bandgap of 2.05 eV, indicating a higher bandgap comparing to the measured optical bandgap of a-InN (1.25 eV) due to doping with boron. Films grown on c-Si(100) were characterized by spectroscopic ellipsometry (SE) technique in the wavelength range of (300-1700) nm. The measured ellipsometric spectra are described well by a two-layer model structure, which consists of a transparent layer on top of an absorbing layer. The thicknesses and optical functions of the transparent and absorbing layers were obtained by analyzing the measured ellipsometric spectra, Ψ and Δ within the framework of the Cauchy–Urbach (CU) and Tauc–Lorentz (TL) models, respectively. While the overlayer is completely transparent over the measured range (k(λ) = 0), the absorbing layer underneath it exhibits a clear absorption above its optical bandgap of 2.15 eV, which is in a good agreement with the SP finding. There was an excellent agreement between the bandgap obtained as a fitting parameter from the optical model and that obtained by linear extrapolation using the empirical Tauc and Cody models for amorphous semiconductors.

Tungsten nitride thin films prepared by MOCVD

1993 ◽  
Vol 8 (6) ◽  
pp. 1353-1360 ◽  
Author(s):  
Hsin-Tien Chiu ◽  
Shiow-Huey Chuang
Keyword(s):  
Thin Films ◽  
Mass Spectroscopy ◽  
Photoelectron Spectroscopy ◽  
Lattice Parameter ◽  
Binding Energies ◽  
Organic Chemical ◽  
Elemental Distribution ◽  
Tungsten Nitride ◽  
Wavelength Dispersive Spectroscopy ◽  
X Ray

Polycrystalline tungsten nitride thin films were grown by low pressure metallo-organic chemical vapor deposition (MOCVD) using (tBuN)2W(NHtBu)2 as the single-source precursor. Deposition of uniform thin films on glass and silicon substrates was carried out at temperatures 723–923 K in a cold-wall reactor, while the precursor was vaporized at 333–363 K. The growth rates were 2–10 nm/min depending on the condition employed. Bulk elemental composition of the thin films, studied by wavelength dispersive spectroscopy (WDS), is best described as WNx (x = 0.7–1.8). The N/W ratio decreased with increasing temperature of deposition. X-ray diffraction (XRD) studies showed that the films have cubic structures with the lattice parameter a = 0.414–0.418 nm. The lattice parameter decreased with decreasing N/W ratio. Stoichiometric WN thin films showed an average lattice parameter a of 0.4154 nm. X-ray photoelectron spectroscopy (XPS) showed that binding energies of the W4f7/2, W4f5/2, and N1s electrons were 33.0, 35.0, and 397.3 eV, respectively. Elemental distribution within the films, studied by secondary ion mass spectroscopy (SIMS) and Auger spectroscopy depth profilings, was uniform. The SIMS depth profiling also indicated that C and O concentrations were low in the film. Volatile products trapped at 77 K were analyzed by gas chromatography–mass spectroscopy (GC–MS) and nuclear magnetic resonance (NMR). Isobutylene, acetonitrile, hydrogen cyanide, and ammonia were detected in the condensable mixtures. Possible reaction pathways were proposed to speculate the origin of these molecules.

Highly Sensitive H2 Sensors Based on Pd- and PdO-Decorated TiO2 Thin Films at Low-Temperature Operation

2016 ◽  
Vol 675-676 ◽  
pp. 277-280 ◽  
Author(s):  
Benjarong Samransuksamer ◽  
Tula Jutarosaga ◽  
Mati Horprathum ◽  
Anurat Wisitsoraat ◽  
Pitak Eiamchai ◽  
...  
Keyword(s):  
Thin Films ◽  
Low Temperature ◽  
Photoelectron Spectroscopy ◽  
Chemical Element ◽  
Operating Temperature ◽  
X Ray Diffraction ◽  
X Ray ◽  
Highly Sensitive ◽  
Dc Reactive Magnetron Sputtering ◽  
Very High

Abstract In this work, the low-temperature H2-sensing properties of palladium (Pd) and palladium oxide (PdO) nanoparticles decorated titanium dioxide (TiO2) thin film were studied. The TiO2 thin films were prepared by the dc reactive magnetron sputtering. The Pd and PdO nanoparticles were sputtered on the top surface of TiO2 surface in order to enhance the sensitivity to the H2 gas. Morphologies, crystal structures, and chemical element of the examiner samples were investigated by the field-emission scanning electron microscopy (FE-SEM), grazing-incident X-ray diffraction (GIXRD), and X-ray photoelectron spectroscopy (XPS), respectively. The effects of the Pd and PdO nanoparticles on H2-sensing performance of TiO2 were investigated over a low concentration range of 150-3,000 ppm H2 at 50-250°C-operating temperatures. This result exhibited that the PdO decorated on TiO2 surface showed very high response to H2 at a low operating temperature of 150°C.

Oxidation state of tungsten oxide thin films used as gate dielectric for zinc oxide based transistors

2012 ◽  
Vol 1494 ◽  
pp. 111-114
Author(s):  
Michael Lorenz ◽  
Marius Grundmann ◽  
Sandra Wickert ◽  
Reinhard Denecke
Keyword(s):  
Thin Films ◽  
Tungsten Oxide ◽  
Photoelectron Spectroscopy ◽  
Gate Dielectric ◽  
Field Effect Transistors ◽  
Stoichiometric Ratio ◽  
Electrical And Optical Properties ◽  
Metal Insulator ◽  
X Ray ◽  
Tungsten Oxide Thin Films

ABSTRACTWe present an investigation of the degree of oxidization of tungsten oxide (WOx) thin films used as gate dielectric for metal-insulator-semiconductor field-effect transistors (MISFET). By means of X-ray photoelectron spectroscopy WOx thin films grown by pulsed-laser deposition at room temperature were investigated. The electrical and optical properties depend significantly on the oxygen pressure during deposition and are affected by the stoichiometric ratio of oxygen and tungsten.

scholarly journals The ZnO-In2O3 Oxide System as a Material for Low-Temperature Deposition of Transparent Electrodes

Materials ◽  
2021 ◽  
Vol 14 (22) ◽  
pp. 6859
Author(s):  
Akhmed Akhmedov ◽  
Aslan Abduev ◽  
Eldar Murliev ◽  
Abil Asvarov ◽  
Arsen Muslimov ◽  
...  
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Low Temperature ◽  
Optoelectronic Devices ◽  
Transparent Electrodes ◽  
Electrical And Optical Properties ◽  
X Ray ◽  
Low Temperature Deposition ◽  
Temperature Deposition ◽  
Ceramic Targets

The development of optoelectronic devices based on flexible organic substrates substantially decreases the possible process temperatures during all stages of device manufacturing. This makes it urgent to search for new transparent conducting oxide (TCO) materials, cheaper than traditional indium-tin oxide (ITO), for the low-temperature deposition of transparent electrodes, a necessary component of most optoelectronic devices. The article presents the results of a vertically integrated study aimed at the low-temperature production of TCO thin films based on a zinc-indium oxide (ZIO) system with acceptable functional characteristics. First, dense and conducting ceramic targets based on the (100-x) mol% (ZnO) + x mol% (In2O3) system (x = 0.5, 1.5, 2.5, 5.0, and 10.0) were synthesized by the spark plasma sintering method. The dependences of the microstructure and phase composition of the ZIO ceramic targets on the In2O3 content have been studied by powder X-ray diffraction, scanning electron microscopy and energy dispersive X-ray spectroscopy methods. Then, a set of ZIO thin films with different Zn/In ratios were obtained on unheated glass substrates by direct current (dc) magnetron sputtering of the sintered targets. Complex studies of microstructure, electrical and optical properties of the deposited films have revealed the presence of an optimal doping level (5 mol% In2O3) of the ZIO target at which the deposited TCO films, in terms of the combination of their electrical and optical properties, become comparable to the widely used expensive ITO.

Hot Filament Assisted CVD of Titanium Nitride Films

1993 ◽  
Vol 327 ◽  
Author(s):  
Sadanand V. Deshpande ◽  
Erdogan Gulari
Keyword(s):  
Thin Films ◽  
Titanium Nitride ◽  
Photoelectron Spectroscopy ◽  
Chemical Vapor ◽  
X Ray Diffraction ◽  
Titanium Chloride ◽  
X Ray ◽  
Aluminum Metallization ◽  
Temperature Deposition ◽  
Hot Filament

AbstractTitanium nitride thin films have been deposited using a novel Hot Filament Chemical Vapor Deposition (HFCVD) technique. In this technique, a resistively heated tungsten wire (∼1700°C) is used to decompose ammonia to obtain highly reactive nitrogen precursor species. This approach allows for low temperature deposition of nitride thin films. In the past, we have used this method to deposit good quality silicon and aluminum nitride films. Titanium nitride thin films have been deposited on Si(100) at substrate temperatures from 500°C to 600°C. These films were characterized using X-ray photoelectron spectroscopy (XPS), X-ray diffraction, Rutherford backscattering spectroscopy (RBS) and scanning electron microscopy. The effects of deposition pressure, substrate temperature and titanium chloride flow rate on film properties have been studied. TiN films with resistivities as low as 80.0 μΩ-cm have been deposited. RBS analysis indicates that the films serve as excellent diffusion barriers for copper and aluminum metallization on silicon.

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