Determination of subband energies and 2DEG characteristics of Al{sub x}Ga{sub 1−x}N/GaN heterojunctions using variational method

Manouchehri, Farzin; Valizadeh, Pouya

doi:10.1116/1.4865562

Title: Determination of subband energies and 2DEG characteristics of Al{sub x}Ga{sub 1−x}N/GaN heterojunctions using variational method

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Abstract

A physics-based model based on the variational method for analyzing the two dimensional electron gas (2DEG) characteristics of polar AlGaN/GaN heterojunctions is developed. The 2DEG carrier concentration, the first and second energy subbands, and the position of the Fermi energy level are calculated for various barrier thicknesses, Al mole fractions, background dopant concentrations, and gate voltages for gated AlGaN/GaN heterojunctions. The results are in good agreement with the data reported based on self-consistent method. Whereas the aforementioned report has dealt with specific values of Al mole fraction, barrier thickness, and unintentional doping level, the present work provides a basis for calculating the 2DEG characteristics for the full range of these parameters. Furthermore, according to the proposed model, the applicability of the triangular approximation of the quantum well in AlGaN/GaN heterojunctions is evaluated.

Authors:: Manouchehri, Farzin; Valizadeh, Pouya

Publication Date:: Sat Mar 15 00:00:00 EDT 2014

OSTI Identifier:: 22258639

Resource Type:: Journal Article

Journal Name:: Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films

Additional Journal Information:: Journal Volume: 32; Journal Issue: 2; Other Information: (c) 2014 American Vacuum Society; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0734-2101

Country of Publication:: United States

Language:: English

Subject:: 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ALUMINIUM NITRIDES; APPROXIMATIONS; ELECTRIC POTENTIAL; ELECTRON GAS; ENERGY LEVELS; GALLIUM NITRIDES; HETEROJUNCTIONS; QUANTUM WELLS; THICKNESS; TWO-DIMENSIONAL CALCULATIONS; VARIATIONAL METHODS

Citation Formats


                    Manouchehri, Farzin, Valizadeh, Pouya, and Kabir, M. Z., E-mail: kabir@encs.concordia.ca. Determination of subband energies and 2DEG characteristics of Al{sub x}Ga{sub 1−x}N/GaN heterojunctions using variational method.  United States: N. p., 2014. 
        Web.  doi:10.1116/1.4865562.

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                    Manouchehri, Farzin, Valizadeh, Pouya, & Kabir, M. Z., E-mail: kabir@encs.concordia.ca. Determination of subband energies and 2DEG characteristics of Al{sub x}Ga{sub 1−x}N/GaN heterojunctions using variational method.  United States.  https://doi.org/10.1116/1.4865562

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                    Manouchehri, Farzin, Valizadeh, Pouya, and Kabir, M. Z., E-mail: kabir@encs.concordia.ca. 2014.  
        "Determination of subband energies and 2DEG characteristics of Al{sub x}Ga{sub 1−x}N/GaN heterojunctions using variational method".  United States.  https://doi.org/10.1116/1.4865562.

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@article{osti_22258639,

  title        = {Determination of subband energies and 2DEG characteristics of Al{sub x}Ga{sub 1−x}N/GaN heterojunctions using variational method},

  author       = {Manouchehri, Farzin and Valizadeh, Pouya and Kabir, M. Z., E-mail: kabir@encs.concordia.ca},

  abstractNote = {A physics-based model based on the variational method for analyzing the two dimensional electron gas (2DEG) characteristics of polar AlGaN/GaN heterojunctions is developed. The 2DEG carrier concentration, the first and second energy subbands, and the position of the Fermi energy level are calculated for various barrier thicknesses, Al mole fractions, background dopant concentrations, and gate voltages for gated AlGaN/GaN heterojunctions. The results are in good agreement with the data reported based on self-consistent method. Whereas the aforementioned report has dealt with specific values of Al mole fraction, barrier thickness, and unintentional doping level, the present work provides a basis for calculating the 2DEG characteristics for the full range of these parameters. Furthermore, according to the proposed model, the applicability of the triangular approximation of the quantum well in AlGaN/GaN heterojunctions is evaluated.},

  doi          = {10.1116/1.4865562},

  url          = {https://www.osti.gov/biblio/22258639},
  journal      = {Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films},

  issn         = {0734-2101},

  number       = 2,

  volume       = 32,

  place        = {United States},

  year         = {Sat Mar 15 00:00:00 EDT 2014},

  month        = {Sat Mar 15 00:00:00 EDT 2014}

}

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