This paper describes the separation between the area and the perimeter current density components of 4H-SiC vertical p+-in diode with a circular Al+ implanted emitter of different diameters in the range 150–$1000~\mu\text {m} $ and for temperatures of measurement in the range 30–290° C. It is shown that before the diode series resistances become dominant, the forward current is given by the sum of an area plus a perimeter component, both of exponential trend with ideality factor 2; while toward high voltages, an area component with exponential trend and ideality factor 1 adds to the previous components. Moreover, this paper shows that forward area and perimeter current density components can be used for a straightforward identification of the parameters controlling the current transport, provided that they can be fit by the pn junction equations in the frame of the abrupt junction …