Electrical characteristics of Cu-doped In 2O 3/Sb-doped SnO 2 ohmic contacts for high-performance GaN-based light-emitting diodes

Joon Ho Oh, Tae Yeon Seong, H. G. Hong, Kyoung Kook Kim, S. W. Yoon, J. P. Ahn

Research output: Contribution to journalArticle

5 Citations (Scopus)


We characterized the electrical and chemical properties of Cu-doped In 2O 3(CIO) (2.5 nm thick)/Sb-doped SnO 2(ATO) (250 nm thick) contacts to p-type GaN by means of current-voltage measurement, scanning transmission electron microscope (STEM) and x-ray photoemission spectroscopy (XPS). The CIO/ATO contacts show ohmic behaviors, when annealed at 530 and 630°C. The effective Schottky barrier heights on diodes made with Ni (5 nm)/Au (5 nm) contacts decrease with increasing annealing temperature. STEM/energy dispersive x-ray (EDX) profiling results exhibit the formation of interfacial In-Ga-Sn-Cu-oxide. XPS results show a shift of the surface Fermi level toward the lower binding energy side upon annealing. Based on the STEM and XPS results, the ohmic formation mechanisms are described and discussed.

Original languageEnglish
Pages (from-to)109-113
Number of pages5
JournalJournal of Electroceramics
Issue number3-4
Publication statusPublished - 2011 Dec 1



  • Light emitting diode
  • Ohmic contact
  • SnO
  • Transparent electrode

ASJC Scopus subject areas

  • Ceramics and Composites
  • Electronic, Optical and Magnetic Materials
  • Materials Chemistry
  • Condensed Matter Physics
  • Electrical and Electronic Engineering
  • Mechanics of Materials

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