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Your search keyword '"Kumar, Manish"' showing total 3 results
Start Over Author "Kumar, Manish" Topic aluminum Publisher american institute of physics
3 results on '"Kumar, Manish"'

1. Simultaneous enhancement of carrier mobility and concentration via tailoring of Al-chemical states in Al-ZnO thin films.

Author

Kumar, Manish, Long Wen, Sahu, Bibhuti B., and Jeon Geon Han

Subjects
*ZINC oxide films, *CHARGE carrier mobility, *SEMICONDUCTOR thin films, *ALUMINUM, *DOPED semiconductors, *CRYSTAL grain boundaries
Abstract

Simultaneously achieving higher carriers concentration and mobility is a technical challenge against up-scaling the transparent-conductive performances of transparent-conductive oxides. Utilizing one order higher dense (~1 × 1011 cm-3) plasmas (in comparison to the conventional direct current plasmas), highly c-axis oriented Al-doped ZnO films have been prepared with precise control over relative composition and chemical states of constituting elements. Tailoring of intrinsic (O vacancies) and extrinsic (ionic Al and zero-valent Al) dopants provide simultaneous enhancement in mobility and concentration of charge carriers. Room-temperature resistivity as low as 4.89 × 10-4 Ω cm along the carrier concentration 5.6 × 1020 cm-3 is obtained in 200 nm thick transparent films. Here, the control of atomic Al reduces the charge trapping at grain boundaries and subdues the effects of grain boundary scattering. A mechanism based on the correlation between electron-hole interaction and carrier mobility is proposed for degenerately doped wide band-gap semiconductors. [ABSTRACT FROM AUTHOR]

Published
2015
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2. Electronic Study of Al substituted La0.7Ca0.3MnO3 Using Photoemission Spectroscopy.

Author

Phase, D. M., Kumar, Manish, Wadikar, A. D., and Choudhary, R. J.

Subjects
*ALUMINUM, *MANGANESE oxides, *PHOTOELECTRON spectroscopy, *SUBSTITUTION reactions, *POLYCRYSTALS, *SOLID state chemistry, *OXIDATION
Abstract

Polycrystalline samples of La0.7Ca0.3Mn1-XAlXO3 (X=0, 0.05, 0.15) are prepared using solid state reaction route. Photoemission spectroscopy measurements were performed on these samples to investigate their electronic properties. Al shows 3+ oxidation state in both Al doped samples while no effect of Al doping is found on the core level spectrum of La 4d and Ca 2p orbitals and they were found in 3+ and 2+ oxidation state respectively in all the samples . Mn 2p core level photoemission measurements indicates that for 5% Al doped sample (lower doping) Al ions replaces the Mn3+ ions while they substitute Mn4+ in 15 % Al doped sample ((higher doping). [ABSTRACT FROM AUTHOR]

Published
2014
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3. Soft X-ray Absorption Spectroscopy of La0.7Ca0.3Mn1-XAlXO3 Thin Films.

Author

Kumar, Manish, Choudhary, R. J., and Phase, D. M.

Subjects
*X-ray absorption, *SPECTRUM analysis, *CALCIUM, *ALUMINUM, *THIN films, *SURFACE phenomenon, *ELECTRONIC structure
Abstract

Epitaxial thin films of rare earth manganites have generated much attention recently due to their rich phase diagram. The electronic structure of these films is playing a very crucial role and demands a fundamental understanding prior to device fabrication. We have investigated the electronic structure of La0.7Ca0.3Mn1-XAlXO3 (X=0, 0.15) epitaxial thin films by soft X-ray absorption spectroscopy technique using the surface sensitive total electron yield (TEY) mode. [ABSTRACT FROM AUTHOR]

Published
2014
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