Procedure for determining diode parameters at very low forward voltage

A technique is proposed to extract the reverse saturation current parameter and ideality factor of semiconductor junctions from the low forward voltage region of the device’s characteristics. The method involves performing a mathematical operation on the experimental data that allows to calculate the parameters at values of forward current smaller than the reverse saturation current. The procedure was tested and its accuracy verified on synthetic I–V characteristics, with and without added simulated experimental error or noise. Good agreement is obtained between the parameters used in modeling and the extracted values. The procedure was also applied to experimentally measured I_B–V_BE characteristics of a real power BJT.