Degradation mechanisms of Ti/Al/Ni/Au-based Ohmic contacts on AlGaN/GaN HEMTs

Hwang, Ya-Hsi; Ahn, Shihyun; Dong, Chen; Zhu, Weidi; Kim, Byung-Jae; Le, Lingcong; Ren, Fan; Lind, Aaron G.; Dahl, James; Jones, Kevin S.; Pearton, Stephen J.; Kravchenko, Ivan I.; Zhang, Ming-Lan

doi:10.1116/1.4919237

Title: Degradation mechanisms of Ti/Al/Ni/Au-based Ohmic contacts on AlGaN/GaN HEMTs

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Abstract

We investigated the degradation mechanism of Ti/Al/Ni/Au-based Ohmic metallization on AlGaN/GaN high electron mobility transistors upon exposure to buffer oxide etchant (BOE). The major effect of BOE on the Ohmic metal was an increase of sheet resistance from 2.89 to 3.69 Ω/ₜafter 3 min BOE treatment. The alloyed Ohmic metallization consisted 3–5 μm Ni-Al alloy islands surrounded by Au-Al alloy-rings. The morphology of both the islands and ring areas became flatter after BOE etching. Lastly, we used energy dispersive x-ray analysis and Auger electron microscopy to analyze the compositions and metal distributions in the metal alloys prior to and after BOE exposure.

Authors:

Hwang, Ya-Hsi ^[1]; Ahn, Shihyun ^[1]; Dong, Chen ^[1]; Zhu, Weidi ^[1]; Kim, Byung-Jae ^[1]; Le, Lingcong ^[1]; Ren, Fan ^[1]; Lind, Aaron G. ^[2]; Dahl, James ^[2]; Jones, Kevin S. ^[2]; Pearton, Stephen J. ^[2]; Kravchenko, Ivan I. ^[3]; Zhang, Ming-Lan ^[4]

Univ. of Florida, Gainesville, FL (United States). Dept. of Chemical Engineering
Univ. of Florida, Gainesville, FL (United States). Dept. of Materials Science and Engineering
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Science (CNMS)
Hebei Univ. of Technology, Tianjing (China). Dept. of Electronic Science and Technology

Publication Date:: Mon Apr 27 00:00:00 EDT 2015

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:: 1265486

Grant/Contract Number:: AC05-00OR22725

Resource Type:: Accepted Manuscript

Journal Name:: Journal of Vacuum Science and Technology. B, Nanotechnology and Microelectronics

Additional Journal Information:: Journal Volume: 33; Journal Issue: 3; Journal ID: ISSN 2166-2746

Publisher:: American Vacuum Society/AIP

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE

Citation Formats


                    Hwang, Ya-Hsi, Ahn, Shihyun, Dong, Chen, Zhu, Weidi, Kim, Byung-Jae, Le, Lingcong, Ren, Fan, Lind, Aaron G., Dahl, James, Jones, Kevin S., Pearton, Stephen J., Kravchenko, Ivan I., and Zhang, Ming-Lan. Degradation mechanisms of Ti/Al/Ni/Au-based Ohmic contacts on AlGaN/GaN HEMTs.  United States: N. p., 2015. 
Web.  doi:10.1116/1.4919237.

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                    Hwang, Ya-Hsi, Ahn, Shihyun, Dong, Chen, Zhu, Weidi, Kim, Byung-Jae, Le, Lingcong, Ren, Fan, Lind, Aaron G., Dahl, James, Jones, Kevin S., Pearton, Stephen J., Kravchenko, Ivan I., & Zhang, Ming-Lan. Degradation mechanisms of Ti/Al/Ni/Au-based Ohmic contacts on AlGaN/GaN HEMTs.  United States.  https://doi.org/10.1116/1.4919237

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                    Hwang, Ya-Hsi, Ahn, Shihyun, Dong, Chen, Zhu, Weidi, Kim, Byung-Jae, Le, Lingcong, Ren, Fan, Lind, Aaron G., Dahl, James, Jones, Kevin S., Pearton, Stephen J., Kravchenko, Ivan I., and Zhang, Ming-Lan. Mon .  
"Degradation mechanisms of Ti/Al/Ni/Au-based Ohmic contacts on AlGaN/GaN HEMTs".  United States.  https://doi.org/10.1116/1.4919237.  https://www.osti.gov/servlets/purl/1265486.

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@article{osti_1265486,

  title        = {Degradation mechanisms of Ti/Al/Ni/Au-based Ohmic contacts on AlGaN/GaN HEMTs},

  author       = {Hwang, Ya-Hsi and Ahn, Shihyun and Dong, Chen and Zhu, Weidi and Kim, Byung-Jae and Le, Lingcong and Ren, Fan and Lind, Aaron G. and Dahl, James and Jones, Kevin S. and Pearton, Stephen J. and Kravchenko, Ivan I. and Zhang, Ming-Lan},

  abstractNote = {We investigated the degradation mechanism of Ti/Al/Ni/Au-based Ohmic metallization on AlGaN/GaN high electron mobility transistors upon exposure to buffer oxide etchant (BOE). The major effect of BOE on the Ohmic metal was an increase of sheet resistance from 2.89 to 3.69 Ω/ₜafter 3 min BOE treatment. The alloyed Ohmic metallization consisted 3–5 μm Ni-Al alloy islands surrounded by Au-Al alloy-rings. The morphology of both the islands and ring areas became flatter after BOE etching. Lastly, we used energy dispersive x-ray analysis and Auger electron microscopy to analyze the compositions and metal distributions in the metal alloys prior to and after BOE exposure.},

  doi          = {10.1116/1.4919237},

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

  number       = 3,

  volume       = 33,

  place        = {United States},

  year         = {Mon Apr 27 00:00:00 EDT 2015},

  month        = {Mon Apr 27 00:00:00 EDT 2015}

}

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