FLEXIBLE, LIGHTWEIGHT AMORPHOUS SILICON SOLAR CELLS TUNED FOR AMO SPECTRUM.

THERE IS A NEED IN SPACE POWER SYSTEM TECHNOLOGIES FOR FLEXIBLE, LIGHTWEIGHT SOLAR ARRAYS WITH SPECIFIC PERFORMANCEIN W/KG EXCEEDING BASELINE THIN SI DESIGN. A NEW TYPE OF AMORPHOUS SILICON SOLAR CELL IS PROPOSED IN WHICH THE DEVICES ARE FABRICATED AND MONOLITHICALLY INTERCONNECTED ON POLYIMIDE FILM, USING CONTINUOUS ROLL-TO-ROLL PROCESSES DDEVELOPED SPECIFICALLY FOR POLYIMIDE. THIS TECHNOLOGY, TAILORED FOR SPACE USE, WILL PROVIDE A GREAT IMPROVEMENT OVER CURRENT TECHNOLOGIES IN BOTH POWER TO WEIGHT RATIO AND COST. THE DEVICE STRUCTURE CONSISTS OF AN A-SI P-I-N DIODE DEPOSITED ON 2 MIL METALIZED POLYIMIDE. A TRANSPARENT CONDUCTOR IS DEPOSITED ON TOP OF THE DIODE STRUCTURE, GIVINGA TOTAL DEVICE THICKNESS OF LESS THAN 1 MICRON. IN PHASE I,WE PROPOSE SEVERAL INNOVATIONS TO ENSURE DEVICE STABILITY AND IMPROVEMENT OF THE DEVICE EFFICIENCY IN THE SPACE ENVIRONMENT. THESE CHANGES INVOLVE (1) MODIFYING THE TOP LAYER TO IMPROVE BLUE AND NEAR UV RESPONSES, (2) ESTABLISHING DEPOSITION PROCEDURES FOR FABRICATING TANDEM JUNCTION DEVICES WITH DIFFERENT BANDGAP A-SI I-LAYERS, AND (3) DEVELOPING A LOWER BANDGAP SIGE BOTTOM LAYER IN THE TANDEM CELL.