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Title: Planar Ohmic Contacts to Al 0.45 Ga 0.55 N/Al 0.3 Ga 0.7 N High Electron Mobility Transistors

Abstract

Here, we present a low resistance, straightforward planar ohmic contact for Al 0.45Ga 0.55N/Al 0.3Ga 0.7N high electron mobility transistors. Five metal stacks (a/Al/b/Au; a = Ti, Zr, V, Nb/Ti; b = Ni, Mo, V) were evaluated at three individual annealing temperatures (850, 900, and 950°C). The Ti/Al/Ni/Au achieved the lowest specific contact resistance at a 900°C anneal temperature. Transmission electron microscopy analysis revealed a metal-semiconductor interface of Ti-Al-Au for an ohmic (900°C anneal) and a Schottky (850°C anneal) Ti/Al/Ni/Au stack. HEMTs were fabricated using the optimized recipe with resulting contacts that had room-temperature specific contact resistances of ρ c = 2.5 × 10 -5 Ω cm², sheet resistances of R SH = 3.9 kΩ/$$\blacksquare$$, and maximum current densities of 75 mA/mm (at VGATE of 2 V). Electrical measurements from -50 to 200°C had decreasing specific contact resistance and increasing sheet resistance, with increasing temperature. These contacts enabled state-of-the-art performance of Al 0.45Ga 0.55N/Al 0.3Ga 0.7N HEMTs.

Authors:
 [1];  [1];  [1];  [1];  [1];  [1];  [1];  [1];  [1];  [1];  [1]
  1. Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)
Publication Date:
Research Org.:
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA)
OSTI Identifier:
1429630
Report Number(s):
[SAND2017-10223J]
[Journal ID: ISSN 2162-8769; 657184]
Grant/Contract Number:  
[AC04-94AL85000; NA- 0003525]
Resource Type:
Accepted Manuscript
Journal Name:
ECS Journal of Solid State Science and Technology
Additional Journal Information:
[ Journal Volume: 6; Journal Issue: 11]; Journal ID: ISSN 2162-8769
Publisher:
Electrochemical Society
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; Electron Devices; Microelectronics-Semiconductor Processing; Semiconductors

Citation Formats

Klein, Brianna A., Baca, Albert G., Armstrong, Andrew M., Allerman, Andrew A., Sanchez, Carlos A., Douglas, Erica A., Crawford, Mary H., Miller, Mary A., Kotula, Paul G., Fortune, Torben R., and Abate, Vincent M. Planar Ohmic Contacts to Al 0.45 Ga 0.55 N/Al 0.3 Ga 0.7 N High Electron Mobility Transistors. United States: N. p., 2017. Web. doi:10.1149/2.0181711jss.
Klein, Brianna A., Baca, Albert G., Armstrong, Andrew M., Allerman, Andrew A., Sanchez, Carlos A., Douglas, Erica A., Crawford, Mary H., Miller, Mary A., Kotula, Paul G., Fortune, Torben R., & Abate, Vincent M. Planar Ohmic Contacts to Al 0.45 Ga 0.55 N/Al 0.3 Ga 0.7 N High Electron Mobility Transistors. United States. doi:10.1149/2.0181711jss.
Klein, Brianna A., Baca, Albert G., Armstrong, Andrew M., Allerman, Andrew A., Sanchez, Carlos A., Douglas, Erica A., Crawford, Mary H., Miller, Mary A., Kotula, Paul G., Fortune, Torben R., and Abate, Vincent M. Sat . "Planar Ohmic Contacts to Al 0.45 Ga 0.55 N/Al 0.3 Ga 0.7 N High Electron Mobility Transistors". United States. doi:10.1149/2.0181711jss. https://www.osti.gov/servlets/purl/1429630.
@article{osti_1429630,
title = {Planar Ohmic Contacts to Al 0.45 Ga 0.55 N/Al 0.3 Ga 0.7 N High Electron Mobility Transistors},
author = {Klein, Brianna A. and Baca, Albert G. and Armstrong, Andrew M. and Allerman, Andrew A. and Sanchez, Carlos A. and Douglas, Erica A. and Crawford, Mary H. and Miller, Mary A. and Kotula, Paul G. and Fortune, Torben R. and Abate, Vincent M.},
abstractNote = {Here, we present a low resistance, straightforward planar ohmic contact for Al0.45Ga0.55N/Al0.3Ga0.7N high electron mobility transistors. Five metal stacks (a/Al/b/Au; a = Ti, Zr, V, Nb/Ti; b = Ni, Mo, V) were evaluated at three individual annealing temperatures (850, 900, and 950°C). The Ti/Al/Ni/Au achieved the lowest specific contact resistance at a 900°C anneal temperature. Transmission electron microscopy analysis revealed a metal-semiconductor interface of Ti-Al-Au for an ohmic (900°C anneal) and a Schottky (850°C anneal) Ti/Al/Ni/Au stack. HEMTs were fabricated using the optimized recipe with resulting contacts that had room-temperature specific contact resistances of ρc = 2.5 × 10-5 Ω cm², sheet resistances of RSH = 3.9 kΩ/$\blacksquare$, and maximum current densities of 75 mA/mm (at VGATE of 2 V). Electrical measurements from -50 to 200°C had decreasing specific contact resistance and increasing sheet resistance, with increasing temperature. These contacts enabled state-of-the-art performance of Al0.45Ga0.55N/Al0.3Ga0.7N HEMTs.},
doi = {10.1149/2.0181711jss},
journal = {ECS Journal of Solid State Science and Technology},
number = [11],
volume = [6],
place = {United States},
year = {2017},
month = {9}
}

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