The wafer now contains p-region and
n-region and a metallurgical junction between p-, and n- region Two important processes occur during the formation of a p-n junction:
diffusion and drift We know that in an n-type semiconductor, the
concentration of electrons (number of electrons per unit volume) is more
compared to the concentration of holes Similarly, in a p-type
semiconductor, the concentration of holes is more than the concentration
of electrons