Low Temperature Preparation of Gallium Nitride Thin Films

1992 ◽  
Vol 242 ◽  
Author(s):  
Roy G. Gordon ◽  
David M. Hoffman ◽  
Umar Riaz
Keyword(s):  
Thin Films ◽  
Gallium Nitride ◽  
Photoelectron Spectroscopy ◽  
Rutherford Backscattering Spectrometry ◽  
Chemical Vapor ◽  
Transmission Electron ◽  
Low Temperature Preparation ◽  
Pressure Chemical ◽  
Substrate Temperatures ◽  
Temperature Preparation

ABSTRACTGallium nitride thin films were prepared by atmospheric pressure chemical vapor deposition from hexakis(dimethylamido)digallium, Ga2(NMe2)6, and ammonia precursors at substrate temperatures of 100–400 °C with growth rates up to 1000 Å/min. The films were characterized by transmission electron microscopy, X-ray photoelectron spectroscopy, Rutherford backscattering spectrometry and forward recoil spectrometry. The N/Ga ratio varied from 1.05 for films deposited at 400 °C to 1.5 at 100 °C. The hydrogen concentration increased from 10 atom % for films deposited at 400 °C to 24 atom % at 100 °C. Films deposited at 100 °C were amorphous but films deposited at higher temperatures were polycrystalline. Bandgaps of the films varied from 3.8 eV for films deposited at 400 °C to 4.2 eV at 100 °C.

Atmospheric Pressure Chemical Vapor Deposition of Gallium Nitride Thin Films

1990 ◽  
Vol 204 ◽  
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.

A STUDY OF ALUMINA THIN FILMS GROWN BY LOW PRESSURE MOCVD: XPS AND AES

2002 ◽  
Vol 16 (08) ◽  
pp. 1261-1267 ◽  
Author(s):  
M. P. SINGH ◽  
S. A. SHIVASHANKAR ◽  
T. SHRIPATHI
Keyword(s):  
Vapor Deposition ◽  
Photoelectron Spectroscopy ◽  
Metalorganic Chemical Vapor Deposition ◽  
Chemical Vapor ◽  
Alumina Film ◽  
Cross Sectional ◽  
X Ray ◽  
Transmission Electron ◽  
Low Pressure Mocvd ◽  
Substrate Temperatures

We have studied the chemical composition of alumina ( Al 2 O 3) films grown on Si(100) at different substrate temperatures by metalorganic chemical vapor deposition (MOCVD) using aluminium acetylactonate { Al(acac) 3} as the precursor. We have found that the resulting films of Al 2 O 3 contain substantial amounts of carbon. X-ray photoelectron spectroscopy (XPS) was employed to study the chemical state of carbon present in such films. The XPS spectrum reveals that the carbon present in Al 2 O 3 film is graphitic in nature. Auger electron spectroscopy (AES) was employed to study the distribution of carbon in the Al 2 O 3 films. The AES depth profile reveals that carbon is present throughout the film. The AES study on Al 2 O 3 films corroborates the XPS findings. An investigation of the Al 2 O 3/ Si (100) interface was carried out using cross-sectional transmission electron microscopy (XTEM). The TEM study reveals textured growth of alumina film on Si(100), with very fine grains of alumina embedded in an amorphous carbon-containing matrix.

Chemical Vapor Deposition of Nickel Ferrite Using Ni C5H5 2 and Fe C5H4C4H9 C5H5

2010 ◽  
Vol 3 (1) ◽  
Author(s):  
Rachel Walker ◽  
M. Singh ◽  
Y. Yang ◽  
C.G. Takoudis
Keyword(s):  
Thin Films ◽  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Photoelectron Spectroscopy ◽  
Nickel Ferrite ◽  
Chemical Vapor ◽  
Silicon Substrates ◽  
Pressure Chemical ◽  
Oxygen Gas ◽  
The Individual

Chemical vapor deposition was used to deposit thin films of nickel oxide (NiO) and iron oxide (Fe2O3) on silicon substrates. Precursors chosen for this process were nickelocene,Ni(C5H5)2 and n-butylferrocene, Fe(C5H4C4H9)(C5H5), which were oxidized with oxygen gas in a low-pressure chemical vapor deposition system. Following the deposition of the individual metal oxides, the two precursors were used together with the goal of depositing a thin film of nickel ferrite (NiFe2O4). Both co-deposition and cyclic deposition were carried out, and the resulting thin films were analyzed using x-ray photoelectron spectroscopy. This study found that the resulting thin films did not contain NiFe2O4, but were composed of NiO and Fe2O3 in a different ratio. It is suggested that changing various parameters in this experiment can be used to vary this ratio.

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

1993 ◽  
Vol 335 ◽  
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.

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

1990 ◽  
Vol 204 ◽  
Author(s):  
Wayne L. Gladfelter ◽  
Jen-Wei Hwang ◽  
Everett C. Phillips ◽  
John F. Evans ◽  
Scott A. Hanson ◽  
...  
Keyword(s):  
Gallium Nitride ◽  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Photoelectron Spectroscopy ◽  
Chemical Vapor ◽  
Cubic Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Pressure Chemical ◽  
Elemental Arsenic

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.

Heteroepitaxial Growth of A1203 Thin Films on Si By Lpcvd

1988 ◽  
Vol 116 ◽  
Author(s):  
M. Ishida ◽  
I. Katakabe ◽  
N. Ohtake ◽  
T. Nakamura
Keyword(s):  
Thin Films ◽  
Chemical Vapor ◽  
Interface State ◽  
State Density ◽  
Gate Insulator ◽  
Heteroepitaxial Growth ◽  
Mos Capacitors ◽  
Pressure Chemical ◽  
Relationship Of ◽  
Substrate Temperatures

AbstractHeteroepitaxial A1203 thin films were grown successfully on Si(lO0) substrates by low—pressure chemical vapor deposition (LP—CVD). The growth was performed at a pressure of 30 Torr by pyrolysis of N2 bubbled AI(CH3)3 and N20 at substrate temperatures above 1000ºC.RHEED patterns indicated that the grown films were ɤ—Al203 single crystals with an orientation relationship of ɤ—Al203(l00)//Si(l00). The ɤ—A1203 films were stable and did not show phase transition after a 1140ºC heat—treatment for 2hr. MOS capacitors with 500—Å—thick A1203 films as a gate insulator showed highfrequency capacitance—voltage (C—V) curves without hysteresis. The A1203 interface state density determined from quasi—static C—V measurements was 1.7 X 1011cm-2eV-1. It can be seen that ɤ—Al203 film is a promising new insulator for Si on Insulator (SOI) structures.

On the Role of the Underlying Microstructure on the Mechanical Properties of Microelectromechanical Systems (MEMS) Materials

2000 ◽  
Vol 657 ◽  
Author(s):  
G. F. Dirras ◽  
G. Coles ◽  
A. J. Wagner ◽  
S. Carlo ◽  
C. Newman ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Mechanical Properties ◽  
Microelectromechanical Systems ◽  
Chemical Vapor ◽  
Xrd Analysis ◽  
Transmission Electron ◽  
Columnar Grains ◽  
Pressure Chemical ◽  
20 Nm

ABSTRACTThe microstructure of Low Pressure Chemical Vapor Deposition (LPCVD) Polycrystalline silicon (Polysilicon) thin films was investigated by means of scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), atomic force microscopy (AFM) and Auger electron spectroscopy (AES). SEM characterization of tensile tested samples showed a brittle like-rupture, along with grooves located at the surface sides of the sample. TEM investigations of as-deposited samples showed equiaxed or fully columnar grains bridging from the bottom to the top of the films. A microstructural coarsening was observed with annealing. In the as-deposited state, the films exhibited a {110} texture as showed by the XRD analysis. The films' top and bottom surfaces were observed to be smooth with a roughness (standard deviation) of about 11nm and 20 nm respectively. A chemical analysis of the thin films showed the presence of carbon and oxygen impurities on the surface and oxygen through the sample as observed in the depth profile. The hypothetical influence of these findings is subsequently discussed in relation to the measured mechanical properties.

Chemical vapor deposition of aluminum nitride thin films

1992 ◽  
Vol 7 (7) ◽  
pp. 1679-1684 ◽  
Author(s):  
Roy G. Gordon ◽  
Umar Riaz ◽  
David M. Hoffman
Keyword(s):  
Chemical Vapor Deposition ◽  
Aluminum Nitride ◽  
Vapor Deposition ◽  
Photoelectron Spectroscopy ◽  
Visible Region ◽  
Chemical Vapor ◽  
Rutherford Backscattering ◽  
Transmission Electron ◽  
Pressure Chemical ◽  
Quartz Substrates

The atmospheric pressure chemical vapor deposition of aluminum nitride coatings from hexakis(dimethylamido)dialuminum, Al2(N(CH3)2)6, and ammonia precursors is reported. The films were characterized by ellipsometry, transmission electron microscopy, x-ray photoelectron spectroscopy, Rutherford backscattering, and forward recoil spectrometry. The films were deposited at 100–500 °C with growth rates up to 1500 Å/min. The films showed good adhesion to silicon, glass, and quartz substrates and were chemically inert. Rutherford backscattering analysis revealed that the N/Al ratio was 1.15 ± 0.05 for films deposited at 100–200 °C and 1.05 ± 0.05 for those deposited at 300–500 °C. Films deposited at 100–200 °C had refractive indexes in the range 1.65–1.80 whereas indexes for films deposited at 300–400 °C were 1.86–2.04. The films were transparent in the visible region. The optical bandgap varied from 5.0 eV for films deposited at 100 °C to 5.77 eV for those deposited at 500 °C. Films deposited at 100–200 °C were amorphous whereas those deposited at 300–500 °C were polycrystalline.

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