2D-Numerical Simulation of Illuminated I-V Characteristic in PIN (NIP) pc-Si Solar Cells Deposited by LPCVD Technique
Résumé
In order to investigate the performance of polycrystalline silicon (pc-Si) p(+)in(+) or n(+)ip(+) solar cells deposited by LPCVD technique, two-dimensional numerical resolution of transport equations in semiconductors devices (Poisson's and continuity equations of electrons and holes) is used. The geometrical model assumes that the pc-Si layer is composed by single crystalline grains separated by amorphous silicon transition zones commonly called grain boundaries which are perpendicular to the growth surface and which include the usual density of states (DOS) with exponential band-tails and Gaussian distributed deep levels. From the simulated results of the illuminated I-V characteristics under AM 1.5 solar spectrum, it is found that the photovoltaic parameters (short circuit current J(SC), conversion efficiency eta, open circuit voltage V-OC and fill factor FF) are strongly sensitive to pc-Si quality layer in terms of grain size, intrinsic layer.