The aim of this work is to provide the basis for the interpretation, under steady state and in the low‐voltage regime of the dark current‐density–voltage (J–V) characteristics of transverse asymmetric amorphous silicon (a‐Si:H)p‐i‐nandn‐i‐pdiodes. The transverse asymmetrica‐Si:H diodes present ratios between the metal contact and the underneath doped layer areas larger than five, leading to the inclusion, in the diode equation, of a lateral leakage current, responsible for the high saturation current density and the forward shape of theJ–Vcurves recorded. The leakage current depends on the lateral spatial potential developed with which varies following a power‐law dependence. The experimentalJ–Vcurves in diodes with the doped layer around the metal contact unetched and etched prove the role and origin of this lateral leakage current and, thus, the proposed model. ©1995 American Institute of Physics.