Atomic layer deposition TiO2-Al2O3 stack: An improved gate dielectric on Ga-polar GaN metal oxide semiconductor capacitors

Wei, Daming; Edgar, James H.; Briggs, Dayrl P.; Srijanto, Bernadeta R.; Retterer, Scott T.; Meyer, III, Harry M.

doi:10.1116/1.4897919

Title: Atomic layer deposition TiO₂-Al₂O₃ stack: An improved gate dielectric on Ga-polar GaN metal oxide semiconductor capacitors

Abstract

This research focuses on the benefits and properties of TiO₂-Al₂O₃ nano-stack thin films deposited on Ga₂O₃/GaN by plasma-assisted atomic layer deposition (PA-ALD) for gate dielectric development. This combination of materials achieved a high dielectric constant, a low leakage current, and a low interface trap density. Correlations were sought between the films’ structure, composition, and electrical properties. The gate dielectrics were approximately 15 nm thick and contained 5.1 nm TiO₂, 7.1 nm Al₂O₃ and 2 nm Ga₂O₃ as determined by spectroscopic ellipsometry. The interface carbon concentration, as measured by x-ray photoelectron spectroscopy (XPS) depth profile, was negligible for GaN pretreated by thermal oxidation in O₂ for 30 minutes at 850°C. The RMS roughness slightly increased after thermal oxidation and remained the same after ALD of the nano-stack, as determined by atomic force microscopy. The dielectric constant of TiO₂-Al₂O₃ on Ga2O3/GaN was increased to 12.5 compared to that of pure Al₂O₃ (8~9) on GaN. In addition, the nano-stack's capacitance-voltage (C-V) hysteresis was small, with a total trap density of 8.74 × 10¹¹ cm^-2. The gate leakage current density (J=2.81× 10^-8 A/cm²) was low at +1 V gate bias. These results demonstrate the promising potential of plasma ALD deposited TiO₂/Al₂O₃ for serving asmore »« less

Authors:

Wei, Daming ^[1]; Edgar, James H. ^[1]; Briggs, Dayrl P. ^[2]; Srijanto, Bernadeta R. ^[2]; Retterer, Scott T. ^[2]; Meyer, III, Harry M. ^[2]

Kansas State Univ., Manhattan, KS (United States)
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Publication Date:: Wed Oct 15 00:00:00 EDT 2014

Research Org.:: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Sciences (CNMS)

Sponsoring Org.:: USDOE Office of Science (SC)

OSTI Identifier:: 1265723

Alternate Identifier(s):: OSTI ID: 1420511

Grant/Contract Number:: AC05-00OR22725; CNMS2013-334

Resource Type:: Accepted Manuscript

Journal Name:: Journal of Vacuum Science and Technology B

Additional Journal Information:: Journal Volume: 32; Journal Issue: 6; Journal ID: ISSN 2166-2746

Publisher:: American Vacuum Society/AIP

Country of Publication:: United States

Language:: English

Subject:: 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY

Citation Formats


                    Wei, Daming, Edgar, James H., Briggs, Dayrl P., Srijanto, Bernadeta R., Retterer, Scott T., and Meyer, III, Harry M. Atomic layer deposition TiO2-Al2O3 stack: An improved gate dielectric on Ga-polar GaN metal oxide semiconductor capacitors.  United States: N. p., 2014. 
Web.  doi:10.1116/1.4897919.

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                    Wei, Daming, Edgar, James H., Briggs, Dayrl P., Srijanto, Bernadeta R., Retterer, Scott T., & Meyer, III, Harry M. Atomic layer deposition TiO2-Al2O3 stack: An improved gate dielectric on Ga-polar GaN metal oxide semiconductor capacitors.  United States.  https://doi.org/10.1116/1.4897919

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                    Wei, Daming, Edgar, James H., Briggs, Dayrl P., Srijanto, Bernadeta R., Retterer, Scott T., and Meyer, III, Harry M. Wed .  
"Atomic layer deposition TiO2-Al2O3 stack: An improved gate dielectric on Ga-polar GaN metal oxide semiconductor capacitors".  United States.  https://doi.org/10.1116/1.4897919.  https://www.osti.gov/servlets/purl/1265723.

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@article{osti_1265723,

  title        = {Atomic layer deposition TiO2-Al2O3 stack: An improved gate dielectric on Ga-polar GaN metal oxide semiconductor capacitors},

  author       = {Wei, Daming and Edgar, James H. and Briggs, Dayrl P. and Srijanto, Bernadeta R. and Retterer, Scott T. and Meyer, III, Harry M.},

  abstractNote = {This research focuses on the benefits and properties of TiO2-Al2O3 nano-stack thin films deposited on Ga2O3/GaN by plasma-assisted atomic layer deposition (PA-ALD) for gate dielectric development. This combination of materials achieved a high dielectric constant, a low leakage current, and a low interface trap density. Correlations were sought between the films’ structure, composition, and electrical properties. The gate dielectrics were approximately 15 nm thick and contained 5.1 nm TiO2, 7.1 nm Al2O3 and 2 nm Ga2O3 as determined by spectroscopic ellipsometry. The interface carbon concentration, as measured by x-ray photoelectron spectroscopy (XPS) depth profile, was negligible for GaN pretreated by thermal oxidation in O2 for 30 minutes at 850°C. The RMS roughness slightly increased after thermal oxidation and remained the same after ALD of the nano-stack, as determined by atomic force microscopy. The dielectric constant of TiO2-Al2O3 on Ga2O3/GaN was increased to 12.5 compared to that of pure Al2O3 (8~9) on GaN. In addition, the nano-stack's capacitance-voltage (C-V) hysteresis was small, with a total trap density of 8.74 × 1011 cm-2. The gate leakage current density (J=2.81× 10-8 A/cm2) was low at +1 V gate bias. These results demonstrate the promising potential of plasma ALD deposited TiO2/Al2O3 for serving as the gate oxide on Ga2O3/GaN based MOS devices.},

  doi          = {10.1116/1.4897919},

  journal      = {Journal of Vacuum Science and Technology B},

  number       = 6,

  volume       = 32,

  place        = {United States},

  year         = {Wed Oct 15 00:00:00 EDT 2014},

  month        = {Wed Oct 15 00:00:00 EDT 2014}

}

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Works referencing / citing this record:

Effect of Composition, Interface, and Deposition Sequence on Electrical Properties of Nanolayered Ta2O5-Al2O3 Films Grown on Silicon by Atomic Layer Deposition
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Li, Junpeng; Wu, Jianzhuo; Liu, Junqing
Nanoscale Research Letters, Vol. 14, Issue 1
DOI: 10.1186/s11671-019-2907-0

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Similar Records

Title: Atomic layer deposition TiO2-Al2O3 stack: An improved gate dielectric on Ga-polar GaN metal oxide semiconductor capacitors

Abstract

Citation Formats

Effect of Composition, Interface, and Deposition Sequence on Electrical Properties of Nanolayered Ta2O5-Al2O3 Films Grown on Silicon by Atomic Layer Deposition journal, March 2019

Title: Atomic layer deposition TiO₂-Al₂O₃ stack: An improved gate dielectric on Ga-polar GaN metal oxide semiconductor capacitors

Effect of Composition, Interface, and Deposition Sequence on Electrical Properties of Nanolayered Ta2O5-Al2O3 Films Grown on Silicon by Atomic Layer Deposition
journal, March 2019