Determining valence band offsets in heterojunctions using a single core-level x-ray photoelectron spectrum

Le Wang; Yingge Du; Scott A. Chambers

doi:10.1116/6.0001103

Compositionally Dependent Band Offsets In Aln/AlxGa1-xN Heterojunctions Measured By Using X-Ray Photoelectron Spectroscopy

MRS Proceedings ◽

10.1557/proc-482-775 ◽

1997 ◽

Vol 482 ◽

Cited By ~ 6

Author(s):

R.A. Beach ◽

E.C. Piquette ◽

R.W. Grant ◽

T.C. McGill

Keyword(s):

Valence Band ◽

Photoelectron Spectroscopy ◽

Valence Band Maximum ◽

Core Level ◽

Band Offset ◽

Valence Band Offset ◽

Band Offsets ◽

Band Maximum ◽

X Ray ◽

Al Content

AbstractAlthough GaN has been extensively studied for applications in both light emitting and high power devices, the AlN/GaN valence band offset remains an area of contention. Values quoted in the literature range from 0.8eV (Martin)[1] to 1.36eV (Waldrop)[2]. This paper details an investigation of the AIN/AlxGa1-xN band offset as a function of alloy composition. We find an AlN/AlxGa1-xN valence band offset that is nearly linear with Al content and an end point offset for AlN/GaN of 1.36 ± 0.1 eV. Samples were grown using radio frequency plasma assisted molecular beam epitaxy and characterized with x-ray photoelectron spectroscopy(XPS). Core-level and valence-band XPS data for AIN (0001) and AlxGa1-xN (0001) samples were analyzed to determine core-level to valence band maximum (VBM) energy differences. In addition, oxygen contamination effects were tracked in an effort to improve accuracy. Energy separations of core levels were obtained from AlN/AlxGa1-xN(0001) heterojunctions. From this and the core-level to valence band maximum separations of the bulk materials, valence band offsets were calculated.

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DICHROISM IN ANGLE-RESOLVED PHOTOEMISSION FROM Pt(111)

Surface Review and Letters ◽

10.1142/s0218625x0200310x ◽

2002 ◽

Vol 09 (02) ◽

pp. 883-888 ◽

Cited By ~ 1

Author(s):

G. H. FECHER ◽

J. BRAUN ◽

A. OELSNER ◽

CH. OSTERTAG ◽

G. SCHÖNHENSE

Keyword(s):

Circular Dichroism ◽

Band Structure ◽

Valence Band ◽

Single Step ◽

Core Level ◽

X Ray ◽

Photoelectron Diffraction ◽

Band Emission ◽

First Results ◽

Circular Dichroïsm

The angular dependence of the circular dichroism in photoemission from Pt(111) was investigated for excitation with VUV and soft X-ray radiation. VUV excitation was used to probe band structure and the circular dichroism for valence band emission. The measurements are compared to full relativistic single step photoemission calculations. XPS was used to investigate the circular dichroism in emission from the 4f core level. In this case, the dichroism is induced by photoelectron diffraction. First results from single step core level calculations are compared to the experimental observations.

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O 1s Core-Level Positions of Bi2Sr2CaCu2O8-x by OKα-Ray Emission

Zeitschrift für Naturforschung A ◽

10.1515/zna-1989-0902 ◽

1989 ◽

Vol 44 (9) ◽

pp. 780-784

Author(s):

F. Burgäzy ◽

C. Politis ◽

P. Lamparter ◽

S. Steeb

Keyword(s):

Binding Energy ◽

Energy Level ◽

Photoelectron Spectrum ◽

Local Density ◽

Binding Energies ◽

Core Level ◽

X Ray ◽

Band Structure Calculations ◽

Density Band ◽

Structure Calculations

Abstract The measured O Kα X-ray emission spectrum of the high-Tc superconductor Bi2Sr2CaCu2O8-x is compared with a spectrum based on local density band structure calculations. By taking also into account the shape of the measured O 1s X-ray photoelectron spectrum an energy level diagram for the O 1s core-level binding energies of the three different oxygen sites is constructed. The O 1s binding energy in the Bi2O2-layers is found to be about the same as that one in the SrO-layers, whereas the binding energy in the CuO2-layers is lower by about 0.5 eV.

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Core-level and valence-band X-ray photoelectron diffraction in UO2(100)

Solid State Communications ◽

10.1016/0038-1098(91)90124-e ◽

1991 ◽

Vol 78 (12) ◽

pp. 1033-1037 ◽

Cited By ~ 4

Author(s):

L.E. Cox ◽

W.P. Ellis

Keyword(s):

Valence Band ◽

Core Level ◽

X Ray ◽

Photoelectron Diffraction

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Valence band and core level X-ray photoelectron spectroscopy of lead sulfide nanoparticle–polymer composites

Surface Science ◽

10.1016/j.susc.2007.08.002 ◽

2007 ◽

Vol 601 (19) ◽

pp. 4648-4656 ◽

Cited By ~ 15

Author(s):

Daniel J. Asunskis ◽

Luke Hanley

Keyword(s):

Polymer Composites ◽

Valence Band ◽

Lead Sulfide ◽

Photoelectron Spectroscopy ◽

Core Level ◽

X Ray

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Determination of the valence band offsets at HfO2 /InN(0001) and InN/In0.3 Ga0.7 N(0001) heterojunctions using X-ray photoelectron spectroscopy

physica status solidi (a) ◽

10.1002/pssa.200983544 ◽

2010 ◽

Vol 207 (6) ◽

pp. 1335-1337 ◽

Cited By ~ 2

Author(s):

Anja Eisenhardt ◽

Andreas Knübel ◽

Ralf Schmidt ◽

Marcel Himmerlich ◽

Joachim Wagner ◽

...

Keyword(s):

Valence Band ◽

Photoelectron Spectroscopy ◽

Band Offsets ◽

X Ray

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Core-level photoemission measurements of valence-band offsets in highly strained heterojunctions: Si-Ge system

Physical Review B ◽

10.1103/physrevb.39.1235 ◽

1989 ◽

Vol 39 (2) ◽

pp. 1235-1241 ◽

Cited By ~ 80

Author(s):

G. P. Schwartz ◽

M. S. Hybertsen ◽

J. Bevk ◽

R. G. Nuzzo ◽

J. P. Mannaerts ◽

...

Keyword(s):

Valence Band ◽

Core Level ◽

Band Offsets ◽

Highly Strained

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Absorption and optical conduction in InSe/ZnSe/InSe thin film transistors

Functional Materials Letters ◽

10.1142/s1793604716500193 ◽

2016 ◽

Vol 09 (02) ◽

pp. 1650019 ◽

Cited By ~ 8

Author(s):

S. E. Al Garni ◽

A. F. Qasrawi

Keyword(s):

Thin Film ◽

Valence Band ◽

Electric Fields ◽

Optical Conductivity ◽

Thin Film Transistor ◽

Free Carrier Absorption ◽

Band Offsets ◽

Dielectric Spectra ◽

X Ray ◽

Alternating Electric Fields

In this work, (n)InSe/(p)ZnSe and (n)InSe/(p)ZnSe/(n)InSe heterojunction thin film transistor (TFT) devices are produced by the thermal evaporation technique. They are characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersion X-ray spectroscopy and optical spectroscopy techniques. While the InSe films are found to be amorphous, the ZnSe and InSe/ZnSe films exhibited polycrystalline nature of crystallization. The optical analysis has shown that these devices exhibit a conduction band offsets of 0.47 and valence band offsets of 0.67 and 0.74[Formula: see text]eV, respectively. In addition, while the dielectric spectra of the InSe and ZnSe displayed resonance peaks at 416 and 528[Formula: see text]THz, the dielectric spectra of InSe/ZnSe and InSe/ZnSe/InSe layers indicated two additional peaks at 305 and 350[Formula: see text]THz, respectively. On the other hand, the optical conductivity analysis and modeling in the light of free carrier absorption theory reflected low values of drift mobilities associated with incident alternating electric fields at terahertz frequencies. The drift mobility of the charge carrier particles at femtoseconds scattering times increased as a result of the ZnSe sandwiching between two InSe layers. The valence band offsets, the dielectric resonance at 305 and 350[Formula: see text]THz and the optical conductivity values nominate TFT devices for use in optoelectronics.

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