Thermodynamically Stable Conducting Films of Intermetallic PtGa2 on Gallium Arsenide

1988 ◽  
Vol 144 ◽  
Author(s):  
Larry P. Sadwick ◽  
Kang L. Wang ◽  
David K. Shuh ◽  
Young K. Kim ◽  
R. Stanley Williams
Keyword(s):  
Gallium Arsenide ◽  
Photoelectron Spectroscopy ◽  
Electron Spectroscopy ◽  
Auger Electron ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
X Ray Diffraction ◽  
X Ray ◽  
Gaas Substrates ◽  
Suitable Temperature

ABSTRACTThe first epitaxial platinum gallium two (PtGa2) films have been grown on gallium arsenide (GaAs) (100) by co-evaporation of the elements under ultra-high vacuum conditions. An electron beam evaporator and a Knudsen cell were used to produce the platinum and gallium beams, respectively. The resulting films and bulk PtGa2 have been characterized by x-ray diffraction, Auger electron spectroscopy, and x-ray photoelectron spectroscopy. The data confirm the PtGa2 stoichiometry and crystal structure of the films, and demonstrate their chemical stability on GaAs (100). This study supports the contention that PtGa2 can be a suitable, temperature stable contact material on GaAs substrates.

Atomic Structure and Spectra

2021 ◽  
pp. 68-146
Author(s):  
Kannan M. Krishnan
Keyword(s):  
Photoelectron Spectroscopy ◽  
Electron Spectroscopy ◽  
Auger Electron ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
X Rays ◽  
X Ray ◽  
Spatially Resolved ◽  
Excitation Processes ◽  
Shell Ionization

We review the structure of atoms to describe allowed intra-atomic electronic transitions following dipole selection rules. Inner shell ionization is followed by characteristic X-ray emission or non-radiative de-excitation processes leading to Auger electrons that involve three atomic levels. Photon incidence also results in characteristic photoelectron emission, reflecting the energy distribution of the electrons in the solid. We present details of laboratory and synchrotron sources of X-rays, and discuss their detection by wavelength or energy-dispersive spectrometers, as well as microanalysis with X-ray (XRF), or electron (EPMA) incidence. Characteristic X-ray intensities are quantified in terms of composition using corrections for atomic number (Z), absorption (A), and fluorescence (F). Electron detectors use electrostatic or magnetic dispersing fields; two common designs are electrostatic hemispheric or mirror analyzers. Auger electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS), used for surface analysis, require ultra-high vacuum. AES is a weak signal, best resolved in a derivative spectrum, shows sensitivity to the chemical state and the atomic environment, provides a spatially-resolved signal for composition mapping, and can be quantified for chemical analysis using sensitivity factors. Finally, we introduce the basics of XPS, a photon-in, electron-out technique, discussed further in §3.

The Nature of Surface Oxides on Magnesium Diboride

2001 ◽  
Vol 689 ◽  
Author(s):  
Chandana Meegoda ◽  
Yu. Paderno ◽  
Michael Trenary
Keyword(s):  
Photoelectron Spectroscopy ◽  
Electron Spectroscopy ◽  
Auger Electron ◽  
Magnesium Diboride ◽  
Line Broadening ◽  
X Ray Diffraction ◽  
X Ray ◽  
Surface Oxides ◽  
Auger Spectra ◽  
Major Surface

ABSTRACTSurface oxides present on polycrystalline MgB2 were characterized by high-resolution x-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES). X-ray diffraction (XRD) measurements were used to determine the MgB2 phases. XRD line broadening analysis reveals a grain size of 40 nm. XPS results show that MgO and B2O3 are the major surface oxides. Auger spectra provide further evidence of the presence of MgO. The B 1s and Mg 2p peaks have been used to quantify the amount of the surface oxides.

The Use of Tris(Trimethylsilyl)Arsine to Deposit GaAs by OMCVD

1990 ◽  
Vol 204 ◽  
Author(s):  
Alan D. Berry ◽  
Andrew P. Purdy ◽  
Richard L. Wells ◽  
James W. Pasterczyk ◽  
James D. Johansen ◽  
...  
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Electron Spectroscopy ◽  
Auger Electron ◽  
Ambient Pressure ◽  
Chemical Vapor ◽  
X Ray Diffraction ◽  
X Ray ◽  
Gaas Substrates ◽  
Low Pressures

ABSTRACTChemical vapor deposition experiments using (Me3Si)3As with either GaCl3 or Me3Ga at ambient pressure have produced films of GaAs on Si and semi-conducting GaAs substrates. The films have been characterized by X-ray diffraction and Auger electron spectroscopy, and each have small amounts of C and O impurities. No desired films were deposited from (C6F5)3GaAs(SiMe3)3 at 500°C and low pressures.

Interaction of Copper With Single Crystal Sapphire

1985 ◽  
Vol 60 ◽  
Author(s):  
A. G. Schrott ◽  
R. D. Thompson ◽  
K. N. Tu
Keyword(s):  
Photoelectron Spectroscopy ◽  
Electron Spectroscopy ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Initial State ◽  
Xps Spectra ◽  
Similar Treatment ◽  
X Ray ◽  
Energy Location ◽  
Single Crystal Sapphire

AbstractThe effect of small coverages of Cu evaporated in ultra-high vacuum (UHV) on A12O3 (0001) surfaces has been investigated by X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES). These surfaces were cleaned either by annealing at 1000°C in O2 or by Ar sputtering. They differ both in their initial state and their interaction with Cu. The XPS spectra from as-deposited Cu on sputtered samples exhibit small shifts in the energy location of the various peaks as compared to those from a Cu standard. Annealing the Cu/sputtered A12O3 structure at 500°C produces a shoulder on the Cu 3d peak as well as a new Cu (L3 M4.5 M4.5) Auger feature. Neither of these effects are observed after similar treatment of the Cu/annealed A12O3 structure. An influence of this different bonding situation on the Cu-sapphire interfacial energy is observed.

Heteroepitaxy and Characterisation Of Ge-Rich SiGe Alloys on GaAs

1990 ◽  
Vol 198 ◽  
Author(s):  
R. Venkatasubramanian ◽  
M.L. Timmons ◽  
M. Mantini ◽  
C.T. Kao ◽  
N.I. Parikh
Keyword(s):  
Electron Spectroscopy ◽  
Silicon Content ◽  
Auger Electron ◽  
Alloy Composition ◽  
X Ray Diffraction ◽  
High Quality ◽  
X Ray ◽  
Gaas Substrates ◽  
Type Conduction

ABSTRACTGrowth of SiGe alloys on GaAs substrates at temperatures as low as 590 °C is described. The growth has been accomplished using the pyrolysis of disilane (Si2H6) and Germane (GeH4) at such temperatures. The layers were characterized electrically and show n-type conduction with a carrier concentration of ~ 1 × 1018 cm−3. The high quality of the SiGe layers are evident in the Rutherford backscattering (RBS) channeling results on SiGe/GaAs structures. A Xmin of 5.6% has been obtained for a Si0.05Ge0 95 layer on GaAs. Xmin increases with increasing silicon content in the SiGe layers. The SiGe alloy layers were studied by x-ray diffraction, and the composition was determined assuming coherent, but tetragonally-distorted growth of SiGe on GaAs. The distortion calculations, based on theoretical elastic-constants, were confirmed using Auger electron spectroscopy to check alloy composition.

Sol-Gel AL2O3 Coatings on SiC Fiber

1991 ◽  
Vol 249 ◽  
Author(s):  
Youming Xiao ◽  
Beng Jit Tan ◽  
Steven L. Suib ◽  
Francis S. Galasso
Keyword(s):  
Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Electron Spectroscopy ◽  
Auger Electron ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Sic Fiber ◽  
Sol Gel Process ◽  
Scanning Electron

ABSTRACTCoating of SiC (BP-SIGMA) fibers with alumina by a sol-gel process did not cause degradation even after heating to 1000°C in air for 24 h. X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Auger electron spectroscopy (AES) and scanning electron microscopy (SEM ) methods were used to study the coating fiber interface.

Sign in / Sign up

Export Citation Format

Share Document