A dynamic velocity at the n-p junction interface has been introduced.
Solar cell structures have been used as diode models. The relationship
of the dynamic velocity with the technological parameters of solar ce
lls and with the junction operating conditions has been considered, Th
e variations of this dynamic velocity with the potential at the juncti
on point out the influence of the base doping level and of the base wi
dth, and allow to differentiate the nature of the cell back contact.