Ni/W/Ni ohmic contacts for both n- and p-type 4H-SiC


In this study, we used a Ni/W/Ni-layered structure to provide low-resistive ohmic contacts with good thermal stability for both n-type and p-type 4H-SiC. As reference, we used Ni and Ni/Ti/Ni as control groups with specific contact resistivities, and we verified the thermal stability of the structures by specific contact resistivity measurements and thermal duration tests. We found that for both n-type and p-type semiconductors, Ni/W/Ni is superior in terms of thermal stability and specific contact resistivity. Using XRD, we also analyzed the components involved in ohmic contact and thermal stability tests.

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This research was supported by the KIAT (Korea Institute for the Advancement of Technology) and supervised by MOTIE (Ministry of Trade, Industry and Energy) (N0001594).

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Correspondence to Kwangsoo Kim.

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Bae, D., Ahn, G., Jeong, C. et al. Ni/W/Ni ohmic contacts for both n- and p-type 4H-SiC. Electr Eng 100, 2431–2437 (2018).

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  • 4H-SiC
  • Ohmic contact
  • Specific contact resistivity
  • Ni/W/Ni
  • Thermal stability