Enhancement-mode Al0.85Ga0.15N/Al0.7Ga0.3N high electron mobility transistor with fluorine treatment

Klein, Brianna A.; Douglas, Erica A.; Armstrong, Andrew M.; Allerman, Andrew A.; Abate, Vincent M.; Fortune, Torben R.; Baca, Albert G.

doi:10.1063/1.5064543

Title: Enhancement-mode Al_0.85Ga_0.15N/Al_0.7Ga_0.3N high electron mobility transistor with fluorine treatment

Abstract

Enhancement-mode Al_0.7Ga_0.3N-channel high electron mobility transistors (HEMTs) were achieved here through a combination of recessed etching and fluorine ion deposition to shift the threshold voltage (V_TH) relative to depletion-mode devices by +5.6 V to V_TH = +0.5 V. Accounting for the threshold voltage shift (ΔV_TH), current densities of approximately 30 to 35 mA/mm and transconductance values of 13 mS/mm were achieved for both the control and enhancement mode devices at gate biases of 1 V and 6.6 V, respectively. Little hysteresis was observed for all devices, with voltage offsets of 20 mV at drain currents of 1.0 × 10^-3 mA/mm. Enhancement-mode devices exhibited slightly higher turn-on voltages (+0.38 V) for forward bias gate currents. Piecewise evaluation of a threshold voltage model indicated a ΔV_TH of +3.3 V due to a gate recess etching of 12 nm and an additional +2.3 V shift due to fluorine ions near the AlGaN surface.

Authors:

Klein, Brianna A. ^[1];

^[1];

^[1]; Allerman, Andrew A. ^[1]; Abate, Vincent M. ^[1];

^[1]; Baca, Albert G. ^[1]

Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

Publication Date:: Tue Mar 19 00:00:00 EDT 2019

Research Org.:: Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

Sponsoring Org.:: USDOE National Nuclear Security Administration (NNSA)

OSTI Identifier:: 1507744

Alternate Identifier(s):: OSTI ID: 1501722

Report Number(s):: SAND2019-2413J
Journal ID: ISSN 0003-6951; 673155

Grant/Contract Number:: NA0003525

Resource Type:: Accepted Manuscript

Journal Name:: Applied Physics Letters

Additional Journal Information:: Journal Volume: 114; Journal Issue: 11; Journal ID: ISSN 0003-6951

Publisher:: American Institute of Physics (AIP)

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE; transconductance; electric measurements; secondary ion mass spectroscopy; semiconductors; two-dimensional electron gas; field effect transistors; electric currents; electrical properties and parameters

Citation Formats


                    Klein, Brianna A., Douglas, Erica A., Armstrong, Andrew M., Allerman, Andrew A., Abate, Vincent M., Fortune, Torben R., and Baca, Albert G. Enhancement-mode Al0.85Ga0.15N/Al0.7Ga0.3N high electron mobility transistor with fluorine treatment.  United States: N. p., 2019. 
Web.  doi:10.1063/1.5064543.

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                    Klein, Brianna A., Douglas, Erica A., Armstrong, Andrew M., Allerman, Andrew A., Abate, Vincent M., Fortune, Torben R., & Baca, Albert G. Enhancement-mode Al0.85Ga0.15N/Al0.7Ga0.3N high electron mobility transistor with fluorine treatment.  United States.  https://doi.org/10.1063/1.5064543

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                    Klein, Brianna A., Douglas, Erica A., Armstrong, Andrew M., Allerman, Andrew A., Abate, Vincent M., Fortune, Torben R., and Baca, Albert G. Tue .  
"Enhancement-mode Al0.85Ga0.15N/Al0.7Ga0.3N high electron mobility transistor with fluorine treatment".  United States.  https://doi.org/10.1063/1.5064543.  https://www.osti.gov/servlets/purl/1507744.

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@article{osti_1507744,

  title        = {Enhancement-mode Al0.85Ga0.15N/Al0.7Ga0.3N high electron mobility transistor with fluorine treatment},

  author       = {Klein, Brianna A. and Douglas, Erica A. and Armstrong, Andrew M. and Allerman, Andrew A. and Abate, Vincent M. and Fortune, Torben R. and Baca, Albert G.},

  abstractNote = {Enhancement-mode Al0.7Ga0.3N-channel high electron mobility transistors (HEMTs) were achieved here through a combination of recessed etching and fluorine ion deposition to shift the threshold voltage (VTH) relative to depletion-mode devices by +5.6 V to VTH = +0.5 V. Accounting for the threshold voltage shift (ΔVTH), current densities of approximately 30 to 35 mA/mm and transconductance values of 13 mS/mm were achieved for both the control and enhancement mode devices at gate biases of 1 V and 6.6 V, respectively. Little hysteresis was observed for all devices, with voltage offsets of 20 mV at drain currents of 1.0 × 10-3 mA/mm. Enhancement-mode devices exhibited slightly higher turn-on voltages (+0.38 V) for forward bias gate currents. Piecewise evaluation of a threshold voltage model indicated a ΔVTH of +3.3 V due to a gate recess etching of 12 nm and an additional +2.3 V shift due to fluorine ions near the AlGaN surface.},

  doi          = {10.1063/1.5064543},

  journal      = {Applied Physics Letters},

  number       = 11,

  volume       = 114,

  place        = {United States},

  year         = {Tue Mar 19 00:00:00 EDT 2019},

  month        = {Tue Mar 19 00:00:00 EDT 2019}

}

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Works referencing / citing this record:

High‐Temperature Operation of Al _x Ga _{1− x} N ( x > 0.4) Channel Metal Oxide Semiconductor Heterostructure Field Effect Transistors with High‐ k Atomic Layer Deposited Gate Oxides
journal, February 2020

Mollah, Shahab; Hussain, Kamal; Floyd, Richard
physica status solidi (a), Vol. 217, Issue 7
DOI: 10.1002/pssa.201900802

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Title: Enhancement-mode Al0.85Ga0.15N/Al0.7Ga0.3N high electron mobility transistor with fluorine treatment

Abstract

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