DARK CURRENT-VOLTAGE CHARACTERISTICS OF TRANSVERSE ASYMMETRIC HYDROGENATED AMORPHOUS-SILICON DIODES

The aim of this work is to provide the basis for the interpretation, u nder steady state and in the low-voltage regime of the dark current-de nsity-voltage (J-V) characteristics of transverse asymmetric amorphous silicon (a-Si:H) p-i-n and n-i-p diodes. The transverse asymmetric a- Si:H diodes present ratios between the metal contact and the underneat h doped layer areas larger than five, leading to the inclusion, in the diode equation, of a lateral leakage current, responsible for the hig h saturation current density and the forward shape of the J-V curves r ecorded. The leakage current depends on the lateral spatial potential developed with which varies following a power-law dependence. The expe rimental J-V curves in diodes with the doped layer around the metal co ntact unetched and etched prove the role and origin of this lateral le akage current and, thus, the proposed model. (C) 1995 American Institu te of Physics.