[فيزيائي 2009]

INTRODUCTION
The two-diode model [1-4], which aims at describing
the dark and illuminated I-V characteristics of p-n junction
solar cells, is widely used to extract relevant device
parameters such as the light-induced current density JL,
the shunt resistance Rsh, the lumped series resistance Rs
and the saturation current densities J01 and J02 of the two
diodes (D1 and D2) [1, 5-8]. Two-diode model fits to
experimentally measured Suns-Voc [9] curves are
particularly useful since metal contacts are not required
and the measurements can thus be performed during
early stages of the cell fabrication sequence [6, 8].
However, in many cases this standard model is not
sufficient to understand the characteristics of real devices
due to non-idealities and three-dimensional current flows
within the cells [2, 3, 10]. In this work we use a simple
distributed series resistance (DSR) model to simulate
Suns-Voc, m-Voc and Jsc-Suns [7] curves. We show that
the presented DSR model is able to explain deviations
between measured and two-diode modelled data that are
frequently observed in these measurements.