X-ray photoelectron spectroscopy study on the CrN surface grown on sapphire substrate to control the polarity of ZnO by plasma-assisted molecular beam epitaxy

AbstractDysprosium oxide (Dy2O3) films are grown epitaxially on high mobility Ge(100) substrates by molecular beam epitaxy system. Reflection high energy electron diffraction patterns and X-ray diffraction spectra show that single crystalline cubic Dy2O3 films are formed on Ge(100) substrates. The epitaxial-relationship is identified as Dy2O3 (110)║Ge(100) and Dy2O3 [001]║Ge[011]. Atomic force microscopy results show that the surface of the Dy2O3 film is uniform, flat and smooth with root mean square surface roughness of about 4.6Å. X-ray photoelectron spectroscopy including depth profiles confirms the composition of the films being close to Dy2O3. TEM measurements reveal a sharp, crystalline interface between the oxide and Ge.

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Structural and Optical Properties of Zn1-XCoXO Thin Films Fabricated by Laser Molecular Beam Epitaxy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.295-297.1958 ◽

2011 ◽

Vol 295-297 ◽

pp. 1958-1963

Author(s):

Jing Zhi Yang ◽

Li Juan Fu ◽

Xiao Peng Qi ◽

Hong Yun Li

Keyword(s):

Thin Films ◽

Molecular Beam Epitaxy ◽

Photoelectron Spectroscopy ◽

Molecular Beam ◽

Ambient Pressure ◽

Visible Region ◽

Hexagonal Structure ◽

Axis Orientation ◽

X Ray ◽

Laser Molecular Beam Epitaxy

Zn1-xCoxO thin films on sapphire (0001) substrates were synthesized by laser molecular beam epitaxy (LMBE) method at various temperatures under a work ambient pressure of 5.0 x 10-5Pa condition. X-ray diffraction (XRD) spectra, UV–visible transmission spectra and X-ray photoelectron spectroscopy (XPS), photoluminescence (PL) spectra were employed to characterize the properties of samples. All samples were of wurtzite hexagonal structure with the preferential c-axis-orientation. Co2+ions incorporated into ZnO lattice and substituted for Zn2+ions. ZnLMM Auger spectrum implied Zn interstitials existed in sample. The optical transmission of all samples was relatively high in visible region. Two PL emission peaks located at 418 nm and 490 nm were assigned to the electron transition from the Zn interstitials to the top of the valence band and from the Zn interstitials to the Zn vacancies, respectively.

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Changes in Optical Properties of GaAsN During Annealing

MRS Proceedings ◽

10.1557/proc-0891-ee11-05 ◽

2005 ◽

Vol 891 ◽

Author(s):

Ting Liu ◽

Sandeep Chandril ◽

Eric D. Schires ◽

Nianqiang Wu ◽

Xinqi Chen ◽

...

Keyword(s):

Optical Properties ◽

Molecular Beam Epitaxy ◽

Quantum Dot ◽

Photoelectron Spectroscopy ◽

Molecular Beam ◽

Annealing Temperature ◽

Emission Spectra ◽

X Ray ◽

Annealing Temperatures ◽

Gaas Substrates

ABSTRACTGaAs1−xNx layers and quantum dot-like structures were grown on (100) GaAs substrates by molecular beam epitaxy. The dependence of photoluminescence emission spectra on annealing temperature is consistent with literature at lower temperatures but after annealing at 750 °C a net red-shift is consistently observed. X-ray photoelectron spectroscopy measurements indicate that for different annealing times and temperatures, the nitrogen and arsenic surface concentrations changed compared to that of as-grown samples, specifically arsenic is lost from the material. Raman measurements are consistent with the trends in photoluminescence and also suggest the loss of arsenic occurs at higher annealing temperatures in both samples capped with GaAs and uncapped samples.

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