We report the fabrication of ScN/GaN isotype (n-n) heterojunctions by plasma-assisted physical vapor deposition (PAPVD) of ScN onto metal-organic chemical vapor deposited (MOCVD) GaN. Two types, corresponding to different temperature growth conditions (900 and 1000 K) for ScN were used. The samples grown at 900 K. display rectifying current-voltage (I-V) behavior with turn on voltage between 1.26 and 1.56 V and ideality factors of 4.61 and 5.90. From capacitance-voltage (C-V) measurements, the "built-in" potential values of approximately 0.06 and 1.00 V on each side of the junction were obtained.