Trimethylamine Gallane as a Precursor to Cubic Gallium Nitride and Gallium Arsenide. Metal Hydride Chemical Vapor Deposition

ABSTRACTCyclo-trigallazane, [H2GaNH2]3, is known to form bulk powders of the new cubic phase of gallium nitride upon pyrolysis. An explanation for this unusual example where the molecular structure of the precursor controls the crystal structure of the solid state product is presented. In a hot-wall atmospheric pressure chemical vapor deposition (CVD) reactor, arsine was found to react with TMAG to form films of polycrystalline GaAs which were characterized by X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). The growth rates for smooth films was 1-4 μm/h. In a low pressure CVD reactor, elemental arsenic vapor was also found to react with the TMAG to give GaAs thin films.

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Deposition and Properties of AlN Films Prepared by Low Pressure CVD with a Metalorganic Precursor

MRS Proceedings ◽

10.1557/proc-335-101 ◽

1993 ◽

Vol 335 ◽

Cited By ~ 3

Author(s):

M. J. Cook ◽

P. K. Wu ◽

N. Patibandla ◽

W. B. Hillig ◽

J. B. Hudson

Keyword(s):

Vapor Deposition ◽

Photoelectron Spectroscopy ◽

Chemical Vapor ◽

Low Pressure ◽

X Ray Diffraction ◽

X Ray ◽

Fiber Coating ◽

Pressure Chemical ◽

Substrate Temperatures ◽

Carbon Concentrations

AbstractAluminum nitride films were deposited on Si (100) and sapphire (1102) substrates by low pressure chemical vapor deposition using the metalorganic precursor trisdimethylaluminum amide, [(CH3)2AlNH2]3. Depositions were carried out in a cold wall reactor with substrate temperatures between 500 and 700 °C and precursor temperatures between 50 and 80 °C. The films were analyzed by X-ray photoelectron spectroscopy, X-ray diffraction, optical microscopy and scanning electron microscopy. The films were generally smooth and adherent with colors ranging from transparent to opaque grey. Cracking and spallation were seen to occur at high film thickness. Deposition rates ranged from 20 to 300 Å/min and increased with both precursor and substrate temperature. Carbon concentrations were small, < 5 at. %, while oxygen concentrations were higher and showed a characteristic profile versus depth in the film. High temperature compatibility testing with sapphire/AlN/MoSi2 samples was carried out to determine film effectiveness as a fiber coating in a composite.

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Chemical Vapor Deposition of Vanadium Oxide Tiiin Films

MRS Proceedings ◽

10.1557/proc-335-329 ◽

1993 ◽

Vol 335 ◽

Author(s):

Ogie Stewart ◽

Joan Rodriguez ◽

Keith B. Williams ◽

Gene P. Reck ◽

Narayan Malani ◽

...

Keyword(s):

Chemical Vapor Deposition ◽

Vanadium Oxide ◽

Vapor Deposition ◽

Chemical Vapor ◽

X Ray Diffraction ◽

X Ray ◽

Glass Substrates ◽

Pressure Chemical ◽

Vanadium Oxide Thin Films ◽

Deposited Films

AbstractVanadium oxide thin films were grown on glass substrates by atmospheric pressure chemical vapor deposition (APCVD) from the reaction of vanadium(IV) chloride with isopropanol and t-butanol. Films were deposited in the temperature range 250 to 450°C. The as-deposited films were a dark greenish color consistent with formation of a lower oxide of vanadium. Annealing a film deposited on Corning 7059 glass in air converted the material to a yellow film. X-ray diffraction of the yellow film revealed the presence of V2O5. Optical spectra of the films are presented. Glass substrates previously coated with conductive fluorine doped tin oxide were coated with V2O5 and evaluated for electrochromic activity.

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Texture Evolution in Si/SiC Layered Structures Deposited on Si(001) by Chemical Vapor Deposition

Journal of Materials Research ◽

10.1557/jmr.1998.0367 ◽

1998 ◽

Vol 13 (9) ◽

pp. 2632-2642 ◽

Cited By ~ 12

Author(s):

L-O. Björketun ◽

L. Hultman ◽

O. Kordina ◽

J-E. Sundgren

Keyword(s):

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Texture Evolution ◽

Chemical Vapor ◽

Columnar Structure ◽

Layer Growth ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Pressure Chemical

Texture evolution in Si/SiC multilayers deposited by atmospheric pressure chemical vapor deposition on carbonized Si(001) substrates was investigated using x-ray diffraction and transmission electron microscopy. SiC layers were epitaxial and (001)-oriented. Si layers deposited on the SiC exhibited a columnar structure with predominantly (110) orientation which could be related to the nucleation. Orientational relationships were Si[111] ║ SiC[110] and Si[112] ║ SiC[110]. Also, a low density of (112)-oriented columns was present. Extensive twinning on the vertical {111} planes within the Si columns led to domains of hexagonal stacking up to 10 nm in size with the presence of 2H-Si and 4H-Si. Subsequent SiC layer growth on the (110)-oriented Si layer resulted in a (110)-oriented SiC layer if the Si layer was carbonized prior to growth.

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Thermal Oxidation of Amorphous Silicon-Boron Alloy

MRS Proceedings ◽

10.1557/proc-105-163 ◽

1987 ◽

Vol 105 ◽

Cited By ~ 6

Author(s):

W. M. Lau ◽

R. Yang ◽

B. Y. Tong ◽

S. K. Wong

Keyword(s):

Chemical Vapor Deposition ◽

Amorphous Silicon ◽

Thermal Oxidation ◽

Vapor Deposition ◽

Photoelectron Spectroscopy ◽

Silicon Oxide ◽

Crystalline Silicon ◽

Chemical Vapor ◽

X Ray ◽

Pressure Chemical

AbstractThe thermal oxidation of amorphous silicon-boron alloy (prepared by low pressure chemical vapor deposition) with boron contents ranged from 0–40% at a temperature range of 25- 700 °C has been carried out. Crystalline silicon and polycrystalline boron have also been studied for comparison purposes. The resultant thin oxide overlayers were characterized by X-ray photoelectron spectroscopy. It was found that both the oxidation of Si and of B are enhanced by mixing of the two elements. The oxidation of boron is significantly slower than silicon. During oxidation of silicon-boron alloy, preferential oxidation of silicon occurs at the oxide/bulk interface and the silicon oxide overlayer advances into the bulk faster than the boron oxide.

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Atmospheric Pressure Chemical Vapor Deposition of Gallium Nitride Thin Films

MRS Proceedings ◽

10.1557/proc-204-95 ◽

1990 ◽

Vol 204 ◽

Cited By ~ 7

Author(s):

Roy G. Gordon ◽

David M. Hoffman ◽

Umar Riaz

Keyword(s):

Gallium Nitride ◽

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Photoelectron Spectroscopy ◽

Atmospheric Pressure ◽

Rutherford Backscattering Spectrometry ◽

Chemical Vapor ◽

Rutherford Backscattering ◽

Transmission Electron ◽

Pressure Chemical

ABSTRACTThe atmospheric-pressure chemical vapor deposition of gallium nitride films from hexakis(dimethylamido)digallium, Ga2(NMe2)6, and ammonia precursors at 200 °C with growth rates up to 1000 Å/min is described. The films were characterized by transmission electron microscopy, X-ray photoelectron spectroscopy and Rutherford backscattering spectrometry. Rutherford backscattering analysis showed that the N/Ga ratio was 1.12–1.17. The films were crystalline with ≃ 5–15 nm crystallites.

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Compositional, Structural, and Optical Characterizations of In1-XGaxN Epilayers Grown by High Pressure Chemical Vapor Deposition

Himalayan Physics ◽

10.3126/hj.v3i0.7267 ◽

2012 ◽

Vol 3 ◽

pp. 6-9 ◽

Cited By ~ 1

Author(s):

Ananta R. Acharya ◽

Brian D. Thoms

Keyword(s):

High Pressure ◽

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Electron Spectroscopy ◽

Auger Electron ◽

Optical Transmission ◽

Chemical Vapor ◽

X Ray Diffraction ◽

X Ray ◽

Pressure Chemical

The compositional, structural and optical characterizations of In1-xGaxN epilayers grown by high pressure chemical vapor deposition have been carried out using Auger electron spectroscopy, x-ray diffraction and optical transmission spectroscopy. Auger electron spectroscopy revealed 14% gallium and 86% indium composition of the total metal contents in the In1-xGaxN epilayers. X-ray diffraction pattern showed three prominent peaks centered at 31.4?, 32.86? and 34.5? which are assigned to In1-xGaxN (0002), In (101) and GaN (0002) Bragg reflexes respectively. These results indicate no macroscopic observable phase separation in the analyzed In1-xGaxN sample. The optical transmission spectroscopy and the Beer-Lambert’s law quatified the absorption band edge to be 1.6 eV for the analyzed In1-xGaxN epilayers.The Himalayan PhysicsVol. 3, No. 32012Page: 6-9

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Synthesis and Characterization of Calcium Phosphate Coatings by Metalorganic Chemical Vapor Deposition

MRS Proceedings ◽

10.1557/proc-550-361 ◽

1998 ◽

Vol 550 ◽

Cited By ~ 2

Author(s):

Y. Gao

Keyword(s):

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Photoelectron Spectroscopy ◽

Metalorganic Chemical Vapor Deposition ◽

Calcium Phosphates ◽

Chemical Vapor ◽

Calcium Pyrophosphate ◽

X Ray Diffraction ◽

X Ray ◽

Metalorganic Chemical

AbstractThin coatings of various calcium phosphates including tricalcium phosphate (TCP), calcium pyrophosphate, and hydroxyapatite were synthesized by plasma-enhanced metalorganic chemical vapor deposition (MOCVD). Structure, composition, and surface morphology of the coatings were characterized by x-ray diffraction, x-ray photoelectron spectroscopy, scanning electron microscopy, and atomic force microscopy. All coatings were very dense and free of cracks. X- ray diffraction showed that the as-grown coatings with the Ca/P ratio of 1.5±0.5 and 1.0±0.5 were crystalline μ- TCP and pyrophosphate, respectively. However, hydroxyapatite coatings with the Ca/P ratio of ∼1.67 were amorphous. The crystalline μ-TCP and pyrophosphate coatings exhibited strong growth texture. The textured orientations varied with different growth temperatures. In addition, the microstructure of the μ-TCP coatings strongly depended on the growth temperatures.

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Chemical Vapor Deposition of Copper Oxide Thin Films

MRS Proceedings ◽

10.1557/proc-250-291 ◽

1991 ◽

Vol 250 ◽

Cited By ~ 2

Author(s):

Yuneng Chang ◽

Glenn L. Schrader

Keyword(s):

Chemical Vapor Deposition ◽

Copper Oxide ◽

Vapor Deposition ◽

Photoelectron Spectroscopy ◽

Chemical Vapor ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Organometallic Precursor ◽

Copper Acetylacetonate

AbstractCopper oxide films were prepared by organometallic chemical vapor deposition of copper acetylacetonate in an oxygen-rich environment. The films were characterized by X-ray diffraction, Auger electron spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy. At 360 °C, Cu2O films were formed for an oxygen pressure of 150 torr and a copper acetylacetonate vapor pressure of 0.2 torr). The Cu2O film was polycrystalline, but the orientation was primarily [111]. Differential scanning calorimetry indicated that O2 assists decomposition of the organometallic precursor during pyrolysis.

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Growth of Hexagonal Gallium Nitride Films On The (111) Surfaces of Silicon with Zinc Oxide Buffer Layers

MRS Proceedings ◽

10.1557/proc-449-367 ◽

1996 ◽

Vol 449 ◽

Cited By ~ 4

Author(s):

Y. Kim ◽

C. G. Kim ◽

K-W. Lee ◽

K-S. Yu ◽

J. T. Park ◽

...

Keyword(s):

Zinc Oxide ◽

Gallium Nitride ◽

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Photoelectron Spectroscopy ◽

Lattice Mismatch ◽

Chemical Vapor ◽

High Energy ◽

Buffer Layers ◽

X Ray

ABSTRACTThe growth of gallium nitride films on sapphire substrates has not been straightforward because of the large lattice mismatch between gallium nitride and sapphire. Zinc oxide is structurally the closest material to gallium nitride and therefore is finding use as the substrate for gallium nitride. Single crystal wafers of zinc oxide are hard to obtain and very expensive. However, a thin layer of zinc oxide on a suitable substrate might solve this problem. In this work, highly c-axis oriented zinc oxide buffer layers were grown on Si(lll) substrates at temperatures 410–540 °C by chemical vapor deposition of bis(2,2,6,6-tetramethyl–3,5-heptanedionato)zinc, Zn(tmhd)2, and the hexagonal GaN films were subsequently deposited on them at 500 °C using the single precursor tris(diethyl -μ-amido-gallium), [(C2H5)2 GaNH2]3. The compound Zn(tmhd)2 was found to require oxygen for the deposition of zinc oxide. In the case of gallium nitride, low pressure chemical vapor deposition of tris(diethyl-μ-amido-gallium) worked reasonably well with or without a carrier gas. The buffer layers and the GaN films were characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), scanning electron microscopy (SEM), and reflection high energy elctron diffraction (RHEED).

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