The Low Specific Ohmic Contact Resistivity of Alloyed Ge—LOW—Content Au on Si—Implanted Electrically—Active GaAs Crystal Layers

ABSTRACTThe author did experiments on ohmic contacts between alloyed goldgerumanium (AuGe) thin film systems and Si–implanted n–type GaAs crystal conductive layers on semi–insulating wafers in order to obtain stable ohmic contacts for source–drain electrodes of Si–implanted metal–semiconductor field–effect–transistor arrays as the tools of investigating semi-insulating GaAs crystallographic–characteristics uniformity. Hot–stage–alloyed low–Ge–content (content in charged AuGe wire: < a few wt.%) AuGe/Au films and GaAs crystal n–type Si–implanted layers showed smooth metallic surface morphology (like gold reflection) and low specific ohmic resistivity (≃10exp.−6 Ω/cm2) (by G.S.Marlow and M.B.Mukunda method) at Room temperature on the condition of typical 0.25 X 10exp.13/cm2− 1 X 10exp.13/cm2 Si dosage at 100keV–200keV and 850°C-15 min capless annealing in 2.7 Torr AsH3+Ar atmosphere for S.I GaAs crystal wafers.