Abstract:
One of the promising methods to enhance the performance of
third generation solar cells is to use compositionally graded layers. The
aim of this work is to study the effect of grading in composition on the
performance of solar cells based on AlGaAs and CZTSSe via numerical
simulation with SCAPS 1D software. The gradient is simultaneously in
the composition and in doping concentration. To attain this goal, we have
optimized the uniform devices as a first step. Then, we have optimized
the usual front, back, double and fully graded device. The most important
observation in AlGaAs is that the open circuit-voltage Voc is much higher
than that of with uniform composition. In the case of KS/ST-CZTSSe The
effect of tow grading profile was investigated fully graded (a) and double
graded (b). Cells with profile (a) has better parameters than all uniform
kesterite and stannite cells. It was found that front grading has a
destroying effect on solar cell parameters. In contrary, cell with profile
(b) with only back grading ameliorates extremely the solar cell
parameters. We showed that a grading strategy with fully graded device
can indeed lead to more favorable trade-off between Jsc and Voc .
