We propose a steady-state empirical activation model for the prediction of the electrical activation efficiency of silicon-implanted gallium nitride. Our model has been implemented into Silvaco’s Victory Process simulator which we utilize to perform an accurate prediction of the dopant activation profiles. The dopant activation strongly influences the device characteristics, which is demonstrated by device simulations of a state-of-the-art junction barrier Schottky rectifier. Our results show that increasing the annealing temperature by fifty degrees Celsius reduces the device’s on-state resistance by one order of magnitude.