ON THE LOW-RESISTANCE AU GE/PD OHMIC CONTACT TO N-GAAS/

We report that a Au/Ge/Pd layered structure can result in low contact resistivities (similar to 10(-6) Omega cm(2)) to n-GaAs processed in t hree temperature ranges (175-200, 340-350, and 425-450 degrees C). The contacts processed below the Au-Ge eutectic temperature (361 degrees C) show good surface and interface morphology, thermal stability, Au w ire bondability, and reproducibility. The ohmic contact formation mech anisms are also presented. (C) 1996 American Institute of Physics.