Low-resistivity and transparent indium-oxide-doped ZnO ohmic contact to p-type GaN

Jae-Hong Lim; Dae-Kue Hwang; Hyun-Sik Kim; Jin-Yong Oh; Jin-Ho Yang; R. Navamathavan; Seong-Ju Park
December 2004
Applied Physics Letters;12/20/2004, Vol. 85 Issue 25, p6191
Academic Journal
We report on the indium-oxide-doped ZnO (IZO) transparent ohmic contact to the p-GaN. The IZO transparent ohmic contact layer was deposited on p-GaN by e-beam evaporation. The transmittance of an IZO film with a thickness of 250 nm was 84%–92% for the light in the wavelength range of 400 and 600 nm. In addition, the IZO contact film yielded a low specific contact resistance of 3.4×10-4 Ω cm2 on p-GaN when annealed at 600 °C for 5 min under a nitrogen ambient. Auger electron spectroscopy and x-ray photoemission spectroscopy analyses of the IZO and p-GaN interface indicated that Ga atoms had out-diffused and an InN phase was formed at the interface region after the thermal annealing process, resulting in a decrease in contact resistance. The light output power of a light-emitting diode (LED) with an IZO ohmic contact layer was increased by 34% at 83 mW of electrical input power compared to that of a LED with a Ni/Au ohmic contact layer.


Related Articles

  • Mechanism of current flow in alloyed ohmic In/GaAs contacts. Blank, T.; Gol’dberg, Yu.; Konstantinov, O.; Nikitin, V.; Posse, E. // Technical Physics;Feb2007, Vol. 52 Issue 2, p285 

    A mechanism of current flow in an alloyed ohmic In contact to low-doped gallium arsenide ( n = 4 × 1015 cm−3) is studied. From the temperature dependence of the contact resistance per unit surface area, it is found that the basic mechanism of current flow is thermionic emission through...

  • The mechanism of current flow in an alloyed In-GaN ohmic contact. Blank, T.; Gol'dberg, Yu.; Konstantinov, O.; Nikitin, V.; Posse, E. // Semiconductors;Oct2006, Vol. 40 Issue 10, p1173 

    The resistance of alloyed In-GaN ohmic contact is studied experimentally. In the temperature range 180–320 K, the resistance per unit area increases with temperature, which is typical of metallic conduction and disagrees with current flow mechanisms associated with thermionic,...

  • Highly low resistance and transparent Ni/ZnO ohmic contacts to p-type GaN. Song, June O; Kim, Kyoung-Kook; Park, Seong-Ju; Seong, Tae-Yeon // Applied Physics Letters;7/21/2003, Vol. 83 Issue 3, p479 

    We report on a promising Ni (5 nm)/Al-doped ZnO (AZO) (450 nm) metallization scheme for low resistance and transparent ohmic contacts to p-GaN (5 × 10[SUP17]cm[SUP-3]). It is shown that the as-deposited Ni/AZO contact shows a nonohmic characteristic due to the insulating nature of the...

  • Comment on “Contact mechanisms and design principles for alloyed Ohmic contacts to n-GaN” [J. Appl. Phys. 95, 7940 (2004)]. Yow-Jon Lin // Journal of Applied Physics;10/1/2006, Vol. 100 Issue 7, p073707 

    The contact mechanism and design principles for alloyed Ohmic contacts to n-GaN were investigated in Mohammad’s paper [J. Appl. Phys. 95, 7940 (2004)]. Mohammad’s study demonstrated that both tunneling and thermionic emission were equally important for low resistivity at the...

  • Thermally driven defect formation and blocking layers at metal-ZnO interfaces. Mosbacker, H. L.; Zgrabik, C.; Hetzer, M. J.; Swain, A.; Look, D. C.; Cantwell, G.; Zhang, J.; Song, J. J.; Brillson, L. J. // Applied Physics Letters;8/13/2007, Vol. 91 Issue 7, p072102 

    The authors used depth-resolved cathodoluminescence spectroscopy and current-voltage measurements to probe the temperature-dependent formation of native point defects and reaction layers at metal-ZnO interfaces and their effect on transport properties. These results identify characteristic...

  • Preparation of Ohmic contacts to GaAs/AlGaAs-core/shell-nanowires. Wirths, S.; Mikulics, M.; Heintzmann, P.; Winden, A.; Weis, K.; Volk, Ch.; Sladek, K.; Demarina, N.; Hardtdegen, H.; Grützmacher, D.; Schäpers, Th. // Applied Physics Letters;1/23/2012, Vol. 100 Issue 4, p042103 

    Ohmic contacts to GaAs/AlGaAs core/shell nanowires are prepared by using a Ni/AuGe/Ni/Au layer system. In contrast to Ohmic contacts to planar GaAs/AlGaAs layer systems here, relatively low alloying temperatures are used in cylindrical geometry. Lowest resistances are found for annealing...

  • Contact mechanisms and design principles for nonalloyed ohmic contacts to n-GaN. Mohammad, S. Noor // Journal of Applied Physics;5/1/2004, Vol. 95 Issue 9, p4856 

    The contact mechanism and design principles for nonalloyed ohmic contacts are investigated. Illustrative studies of various contacts show wide validity of the design principles. Experimental measurement suggests that reactive ion etching (RIE) of the n-GaN surface creates extra electrons. There...

  • Dependence of the mechanism of current flow in the in- n-GaN alloyed ohmic contact on the majority carrier concentration. Bessolov, V. N.; Blank, T. V.; Goldberg, Yu. A.; Konstantinov, O. V.; Posse, E. A. // Semiconductors;Nov2008, Vol. 42 Issue 11, p1315 

    Based on the study of the temperature dependence of resistance of the In- n-GaN alloyed ohmic contacts, it is found that the mechanism of current flow in them substantially depends on the concentration N of uncompensated donors in GaN. At N = 5 × 1016 − 1 × 1018 cm−3, current...

  • Contacts to p-type ZnMgO. Kim, Suku; Kang, B.S.; Ren, F.; Heo, Y.W.; Ip, K.; Norton, D.P.; Pearton, S.J. // Applied Physics Letters;3/15/2004, Vol. 84 Issue 11, p1904 

    Ohmic and Schottky contacts to p-type Zn[sub 0.9]Mg[sub 0.1]O are reported. The lowest specific contact resistivity of 3×10[sup -3] Ω cm[sup 2] was obtained for Ti/Au annealed at 600 °C for 30 s. Ni/Au was less thermally stable and showed severe degradation of contact morphology at...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics