Mechanism of current flow and temperature dependence of contact resistivity in Au-Pd-Ti-Pd-n⁺ -GaN ohmic contacts

• Published in: Semiconductor Physics Quantum Electronics & Optoelectronics
• Date: 2013
• Main Authors: Sachenko, A.V., Belyaev, A.E., Boltovets, N.S., Kapitanchuk, L.M., Klad’ko, V.P., Konakova, R.V., Kuchuk, A.V., Korostinskay, T.V., Pilipchuk, A.S., Sheremet, V.N., Mazur, Yu.I., Ware, M.E., Salamo, G.J.
• Format: Article
• Language: English
• Published: Інститут фізики напівпровідників імені В.Є. Лашкарьова НАН України 2013
• Online Access: https://nasplib.isofts.kiev.ua/handle/123456789/117817
• Journal Title: Digital Library of Periodicals of National Academy of Sciences of Ukraine
• Cite this: Mechanism of current flow and temperature dependence of contact resistivity in Au-Pd-Ti-Pd-n⁺ -GaN ohmic contacts / A.V. Sachenko, A.E. Belyaev, N.S. Boltovets, L.M. Kapitanchuk, V.P. Klad’ko, R.V. Konakova, A.V. Kuchuk, T.V. Korostinskaya, A.S. Pilipchuk, V.N. Sheremet, Yu.I. Mazur, M.E. Ware, G.J. Salamo // Semiconductor Physics Quantum Electronics & Optoelectronics. — 2013. — Т. 16, № 4. — С. 313-321. — Бібліогр.: 32 назв. — англ.

We present the results of structural and morphological investigations of
 interactions between phases in the layers of Au-Pd-Ti-Pd-n⁺-GaN contact metallization that appear at rapid thermal annealing (RTA). It is shown that formation of ohmic contact
 occurs in the course of RTA at Т = 900°C due to formation of titanium nitride. We
 studied experimentally and explained theoretically the temperature dependence of
 contact resistivity ρс(Т) of ohmic contacts in the 4.2-380 K temperature range. The ρс(Т)
 curve was shown to flatten out in the 4.2-50 K range. As temperature grew, ρс decreased
 exponentially. The results obtained enabled us to conclude that current flow has field
 nature at saturation of ρс(Т) and the thermofield nature in the exponential part of ρс(Т)
 curve.