OPTICAL OPTIMIZATION OF MULTIJUNCTION THIN FILM SILICON: HYDROGEN SOLAR CELLS

TO ACHIEVE THE PREDICTED HIGH POWER CONVERSION EFFICIENCIES OF MULTIJUNCTION AMORPHOUS SILICON SOLAR CELLS (A:SI), EFFICIENT USE OF ALL INCOMING SOLAR RADIATION IS NECESSARY. MULTIJUNCTION SOLAR CELL DEVICES ARE EFFICIENT COLLECTORS OFINCIDENT LIGHT, IN THEORY, BECAUSE LIGHT WITH ENERGY LESS THAN THE BANDGAP EDGE OF THE FIRST JUNCTION MAY BE EFFECTIVELY ABSORBED BY THE JUNCTION BELOW. IN PRACTICE, SIGNIFICANT REFLECTANCE LOSSES OCCUR BECAUSE OF OPTICALLY MISMATCHED LAYERS. AN INNOVATIVE SOLUTION TO THIS PROBLEM IS THE USE OF OPTICALLY OPTIMIZED, THIN FILM MULTILAYER FRONT AND BACK CONTACT DESIGNS. THE OBJECTIVE OF THE PROJECT IS TO INVESTIGATE A NOVEL DESIGN APPROACH FOR OPTICALLY OPTIMIZED FRONT AND BACK CONTACT CONFIGURATIONS FOR A TANDEM A:SI SOLAR CELL DEVICE. THE OPTIMIZED THIN FILM STACKS SERVE TO REDUCE REFLECTION LOSSES AS WELL AS TO MAXIMIZE THE TRANSMISSION OF INCIDENT LIGHT TO THE DEVICE BELOW.