An improved forward I-V method for nonideal Schottky diodes with high series resistance

Abstract

Two methods are described to obtain the value of the series resistance(R)of a Schottky diode from its forward I-V characteristic. The value ofRis then used to plot the curve ln (I) versusV_{D} (= V - IR)which becomes a straight line even if ln(I)versusVdoes not. The ideality factornand the Schottky-barrier height\Phi_{B0}of the diode then follow from the standard procedure. The main advantages of the methods are: 1) a linear regression can be used to calculate the value ofR, 2) many data points are used over the whole data range which raises the accuracy of the results, and 3) the validity of constantRassumption can be checked by the linearity of the ln(I)versus VDcurve. The methods are illustrated on the experimental data of a real diode.