Abstract
Indium tin oxide (ITO) thin films doped with Au, Ni, or Pt (3.5 at.% to 10.5 at.%) were deposited on p-GaN epilayers (Mg ~4 × 1019 cm−3) using direct-current (DC) sputter codeposition. It was found that undoped ITO con- tacts to p-GaN exhibited leaky Schottky behavior, whereas the incorporation of a small amount of Au (3.5 at.% to 10.5 at.%) significantly improved their ohmic characteristics. Compared with standard Ni/ITO contacts, the Au-doped ITO contacts had a similar specific contact resistance in the low 10−2 Ω cm−2 range, but were more stable above 600°C and more transparent at blue wavelengths. These results provide support for the use of Au-doped ITO ohmic contact to p-type GaN in high-brightness blue light-emitting diodes.
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Guo, H., Andagana, H.B. & Cao, X.A. Au-Doped Indium Tin Oxide Ohmic Contacts to p-Type GaN. J. Electron. Mater. 39, 494–498 (2010). https://doi.org/10.1007/s11664-010-1133-4
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DOI: https://doi.org/10.1007/s11664-010-1133-4