Low resistivity ohmic contacts on lightly doped n-type -Ga2O3 using Mg/Au

Mg/Au stacks were introduced to prepare ohmic contact at different annealing temperatures on Sn lightly doped -Ga2O3. Linear current-voltage characteristics were realized when the annealing temperatures were 300, 400 and 500 degrees C. The transmission line measurements were used to extract the specific contact resistance ((c)) of the annealed samples. The (c) decreased as annealing temperature increased and a minimum (c) of 2.1x10(-5)cm(2) was obtained for the sample annealed at 500 degrees C. However, the contact electrodes with the (c) of 1.3x10(-4)cm(2) after annealing at 400 degrees C had better surface profile and stability. The ohmic contact mechanism and stability of electrodes were discussed in details.