On the low resistance Au/Ge/Pd ohmic contact to n-GaAs

Abstract
We report that a Au/Ge/Pd layered structure can result in low contact resistivities (∼10−6 Ω cm2) to n‐GaAs processed in three temperature ranges (175–200, 340–350, and 425–450 °C). The contacts processed below the Au–Ge eutectic temperature (361 °C) show good surface and interface morphology, thermal stability, Au wire bondability, and reproducibility. The ohmic contact formation mechanisms are also presented.