[17p-W2_401-1~17] 15.4 III-V-group nitride crystals

3:00 PM - 3:15 PM JST(6:00 AM - 6:15 AM UTC)

[17p-W2_401-6] Quantum injection crossover in ultra-degenerate GaN/metal interfaces

〇Kohei Ueno¹, Kohei Okabe¹, Aiko Naito¹, Hiroshi Fujioka¹ (1.IIS, UTokyo)

Keywords:

contact resistivity,GaN

Conventional metal/semiconductor contacts have been described by TFE/FE models, which predict intrinsically high contact resistivity for wide-bandgap semiconductors due to unfavorable tunneling parameters. We demonstrated an extremely low contact resistivity of 5.8×10^-9 Ωcm² on heavily Ge-doped GaN (n = 4×10²⁰ cm^-3), approaching within one order of the Landauer quantum injection limit and comparable to InAs/InGaAs despite very different material properties. By re-plotting ρ_C as a function of the normalized tunneling parameter E₀₀/k_BT, we found that while wide-gap materials show higher resistivity in the TFE/FE transition region, GaN reaches a high-E₀₀/k_BT regime where a plateau appears. This suggests a transition of the limiting mechanism from depletion-layer tunneling to a quantum injection limit at the metal/semiconductor interface.