Abstract
Thin p-doped InGaN layers on p-doped GaN were successfully used to demonstrate a new type of low-resistance ohmic contact. A significant reduction of specific contact resistance can be achieved by increasing the free-hole concentration and the probability for hole tunneling through the Schottky barrier as a consequence of polarization-induced band bending. As obtained from the transmission-line method, the specific contact resistances of Ni (10 nm)/Au (30 nm) contacts deposited on InGaN capping layers were 1.2×10−2 Ωcm2 and 6×10−2 Ωcm2 for capping layer thicknesses of 20 nm and 2 nm, respectively.
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Gessmann, T., Li, Y.L., Waldron, E.L. et al. Novel type of ohmic contacts to p-doped GaN using polarization fields in thin InxGa1−xN capping layers. J. Electron. Mater. 31, 416–420 (2002). https://doi.org/10.1007/s11664-002-0094-7
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DOI: https://doi.org/10.1007/s11664-002-0094-7