New Insights into the Role of Weak Electron–Phonon Coupling in Nanostructured ZnO Thin Films

High-quality crystalline nanostructured ZnO thin films were grown on sapphire substrates by reactive sputtering. As-grown and post-annealed films (in air) with various grain sizes (2 to 29 nm) were investigated by scanning electron microscopy, X-ray diffraction, and Raman scattering. The electron–phonon coupling (EPC) strength, deduced from the ratio of the second- to the first-order Raman scattering intensity, diminished by reducing the ZnO grain size, which mainly relates to the Fröhlich interactions. Our finding suggests that in the spatially quantum-confined system the low polar nature leads to weak EPC. The outcome of this study is important for the development of nanoscale high-performance optoelectronic devices.

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Raman scattering from impurities in semiconductors. II. Special cases

Canadian Journal of Physics ◽

10.1139/p78-073 ◽

1978 ◽

Vol 56 (5) ◽

pp. 560-564

Author(s):

Robert Barrie ◽

H. -C. Chow

Keyword(s):

Raman Scattering ◽

General Result ◽

Phonon Scattering ◽

Phonon Coupling ◽

Strong Electron ◽

Impurities In Semiconductors ◽

Electron Phonon Coupling ◽

Special Cases ◽

Weak Electron

Special cases of the general result for Raman scattering from an impurity in a semiconductor are discussed. For weak electron–phonon coupling the zero-phonon and one-phonon scattering intensities are derived. For strong electron–phonon coupling a comparison is made between two different approximations that have been previously used.

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Anomalous low-temperature Raman scattering in a–Si1−xHx

Journal of Materials Research ◽

10.1557/jmr.1995.1362 ◽

1995 ◽

Vol 10 (6) ◽

pp. 1362-1370 ◽

Cited By ~ 3

Author(s):

D.M. Bhusari ◽

Alka Kumbhar ◽

S.T. Kshirsagar

Keyword(s):

Thin Films ◽

Low Temperature ◽

Raman Scattering ◽

Cross Section ◽

Hydrogenated Amorphous Silicon ◽

Phonon Coupling ◽

Scattered Intensity ◽

Electron Phonon Coupling ◽

Scattering Measurements ◽

Hydrogenated Amorphous

We have reported here on low-temperature Raman scattering measurements on thin films of hydrogenated amorphous silicon (α-Si:H) alloys having different H contents. The Stoke's intensity, 77KITO, scattered at 77 K by the TO-phonon is found to be several times greater than its corresponding magnitude (300KITO) at 300 K. The ratio (77KITO/300KITO) is observed to vary exponentially with an increase in H concentration of the film. After eliminating various possible contributions to the scattering cross section, and therefore to the scattered intensity, this anomalous light scattering at 77 K is attributed to the possibility of polarizability modulation, which is believed to be caused due to a possible reduction in light-induced migration of H in α-Si:H and to the charge-carrier-induced enhancement of electron phonon coupling at 77 K.

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Large electronic sputtering yield of nanodimensional Au thin films: Dominant role of thermal conductivity and electron phonon coupling factor

Journal of Applied Physics ◽

10.1063/1.4977845 ◽

2017 ◽

Vol 121 (9) ◽

pp. 095308 ◽

Cited By ~ 13

Author(s):

Udai B. Singh ◽

Compesh Pannu ◽

Dinesh C. Agarwal ◽

Sunil Ojha ◽

Saif A. Khan ◽

...

Keyword(s):

Thin Films ◽

Thermal Conductivity ◽

Dominant Role ◽

Coupling Factor ◽

Phonon Coupling ◽

Electron Phonon Coupling ◽

Sputtering Yield ◽

Au Thin Films

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Raman Scattering and Superconductivity of Alkali-Fullerene Materials

MRS Proceedings ◽

10.1557/proc-270-179 ◽

1992 ◽

Vol 270 ◽

Author(s):

J. S. Lannin ◽

M. G. Mitch ◽

W. Bacsa ◽

S. J. Chase

Keyword(s):

Thin Films ◽

Raman Scattering ◽

Raman Spectra ◽

Solid Solutions ◽

Thick Films ◽

Ultrathin Film ◽

Phonon Coupling ◽

Electron Phonon Coupling ◽

Scattering Measurements ◽

Different Thickness

ABSTRACTRaman scattering measurements in alkali—fullerene alloys in ultrathin and thin films provide evidence for variations in electron—phonon coupling. For x — 3similar behavior of Rb3 C60 films of different thickness support substantial electron—phonon induced damping of specific Hg(i) modes derived from intramolecular modes of C60. In 400A thick films a reduction of induced scattering from Raman inactive C60 modes substantiates the importance ofHg(2), but not Hg(3) modes for phonon—mediated superconductivity. In contrast to RbxC60 and KxC60 ultrathin film solid solutions, similar Raman spectra for NaxC60 indicate substantially reduced coupling consistent with the absence of superconductivity in this system.

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Size dependent electron–phonon coupling in N, Li, In, Ga, F and Ag doped ZnO thin films

Spectrochimica Acta Part A Molecular and Biomolecular Spectroscopy ◽

10.1016/j.saa.2012.08.076 ◽

2012 ◽

Vol 98 ◽

pp. 453-456 ◽

Cited By ~ 14

Author(s):

S.S. Shinde ◽

C.H. Bhosale ◽

K.Y. Rajpure

Keyword(s):

Thin Films ◽

Zno Thin Films ◽

Phonon Coupling ◽

Size Dependent ◽

Electron Phonon Coupling ◽

Doped Zno

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Resonance and antiresonance in Raman scattering in GaSe and InSe crystals

Scientific Reports ◽

10.1038/s41598-020-79411-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

M. Osiekowicz ◽

D. Staszczuk ◽

K. Olkowska-Pucko ◽

Ł. Kipczak ◽

M. Grzeszczyk ◽

...

Keyword(s):

Raman Scattering ◽

Temperature Effect ◽

Band Gap ◽

Raman Spectra ◽

Quantum Interference ◽

Optical Band Gap ◽

Phonon Coupling ◽

Phonon Modes ◽

Electron Phonon Coupling ◽

Resonant Raman

AbstractThe temperature effect on the Raman scattering efficiency is investigated in $$\varepsilon$$ ε -GaSe and $$\gamma$$ γ -InSe crystals. We found that varying the temperature over a broad range from 5 to 350 K permits to achieve both the resonant conditions and the antiresonance behaviour in Raman scattering of the studied materials. The resonant conditions of Raman scattering are observed at about 270 K under the 1.96 eV excitation for GaSe due to the energy proximity of the optical band gap. In the case of InSe, the resonant Raman spectra are apparent at about 50 and 270 K under correspondingly the 2.41 eV and 2.54 eV excitations as a result of the energy proximity of the so-called B transition. Interestingly, the observed resonances for both materials are followed by an antiresonance behaviour noticeable at higher temperatures than the detected resonances. The significant variations of phonon-modes intensities can be explained in terms of electron-phonon coupling and quantum interference of contributions from different points of the Brillouin zone.

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Depositing High-Performance Conductive Thin Films by Using Atomic Layer Deposition

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.764-765.138 ◽

2015 ◽

Vol 764-765 ◽

pp. 138-142 ◽

Cited By ~ 1

Author(s):

Fa Ta Tsai ◽

Hsi Ting Hou ◽

Ching Kong Chao ◽

Rwei Ching Chang

Keyword(s):

Thin Films ◽

Atomic Layer Deposition ◽

High Performance ◽

Atomic Layer ◽

Electric Properties ◽

X Ray Diffraction ◽

Layer Deposition ◽

Azo Thin Film ◽

Aluminum Doped Zinc Oxide ◽

Conductive Thin Films

This work characterizes the mechanical and opto-electric properties of Aluminum-doped zinc oxide (AZO) thin films deposited by atomic layer deposition (ALD), where various depositing temperature, 100, 125, 150, 175, and 200 °C are considered. The transmittance, microstructure, electric resistivity, adhesion, hardness, and Young’s modulus of the deposited thin films are tested by using spectrophotometer, X-ray diffraction, Hall effect analyzer, micro scratch, and nanoindentation, respectively. The results show that the AZO thin film deposited at 200 °C behaves the best electric properties, where its resistance, Carrier Concentration and mobility reach 4.3×10-4 Ωcm, 2.4×1020 cm-3, and 60.4 cm2V-1s-1, respectively. Furthermore, microstructure of the AZO films deposited by ALD is much better than those deposited by sputtering.

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