Modeling real junctions by a series combination of two ideal diodes with parallel resistance and its parameter extraction

A technique is proposed to extract the reverse saturation current parameter and ideality factor of semiconductor junctions from the low forward voltag e region of the device's characteristics, even under the presence of signif icant parallel resistance effects. The series combination of two ideal diod es is proposed for modeling real devices with a nonlinear contact resistanc e, in which case, the effective ideality factor at high voltage is higher t han that of low voltage. It is proved, under certain physical assumptions, that the series combination of two ideal diodes can be modeled as a single effective diode for low voltage and another effective diode for high voltag e. Both techniques were tested and their accuracy verified on experimental and simulated I V characteristics. (C) 2001 Published by Elsevier Science L td.