Objectif MATERIAL COST IS THE MAIN DRAWBACK OF GAAS SOLAR CELLS, FOR THIS REASON MAINLY CONCENTRATOR CELLS HAVE BEEN PREVIOUSLY STUDIED AND EXPERIMENTED. HOWEVER ANOTHER POSSIBILITY TO REDUCE THE COST CONTRIBUTION IS THE FABRICATION OF MONOCRYSTALLINE GAAS CELLS WITH A THICKNESS RANGING FROM 5 TO 10 MICROMETRES AND SUITABLE FOR FLAT PANEL SOLAR ARRAYS. AIM OF THIS WORK IS THE FABRICATION OF SINGLE CRYSTAL GAAS HOMOJUNCTION SOLAR CELLS, FEW MICROMETERS THIN WITH A CONVERSION EFFICIENCY SIMILAR TO THAT OF THICK DEVICES. THE OPTIMAL GROWTH DIRECTIONS ON THE GAAS SUBSTRATE SURFACE, CORRESPONDING TO THE MAXIMUM LATERAL GROWTH, HAVE BEEN IDENTIFIED USING A CIRCULAR TEST PATTERN. SEVERAL EPITAXIAL STRUCTURES HAVE BEEN DEPOSITED USING THE VPE SYSTEM, ON (110) OREINTED SUBSTRATES MASKED WITH A SIO2 SLITMASK. BEFORE THE EPITAXIAL FILM BECOMES CONTINUOUS, THE SHPE OF THE GROWING FILM IS CHARACTERIZED BY FOUR GROWTH DIRECTIONS. THE RELATIONSHIP BETWEEN THE GROWTH CONDITIONS (E.G. TEMPERATURE, AS MOLAR FRACTION, ETC.) AND THE FILM MORPHOLOGY HAVE BEEN STUDIED AND IDENTIFIED. THE LATERAL TO VERTICAL GROWTH RATE IS ABOUT ONE TO FIVE. SEVERAL FILMS, 10 UM THICK, HAVE BEEN SEPARATED FROM THE GAAS SUBSTRATE AND CHARACTERIZED FROM THE MORPHOLOGICAL POINT OF VIEW. CONTINUOUS FILMS UP TO 1CM2 HAVE BEEN SUCCESSFULLY OBTAINED SUITABLE TO MAKE HIGH EFFICIENCY, LIGHT-WIGHT, LOW-COST GAAS SOLAR CELLS. THE FABRICATION AND SEPARATION OF THIN GAAS FILMS FROM THE SUBSTRATE HAS BEEN SUCCESSFULLY ACHIEVED AND THE GAAS FILMS FROM THE SUBSTRATE HAS BEEN SUCCESSFULLY ACHIEVED AND THE GAAS SUBSTRATES HAVE BEEN REUTILIZED FOR FURTHER GROWTH PROCESSES. THIS IS THE FIRST TIME, TO OUR KNOWLEDGE, THAT THE CLEFT PROCESS DEVELOPED BY MIT HAS BEEN REPRODUCED IN AN ANOTHER LABORATORY. Champ scientifique engineering and technologymaterials engineeringcoating and films Programme(s) FP1-ENNONUC 3C - Research and development programme (EEC) in the field of Non-Nuclear Energy, 1985-1988 Thème(s) Data not available Appel à propositions Data not available Régime de financement CSC - Cost-sharing contracts Coordinateur CISE - Centro Informazioni Studi ed Esperienze SpA Contribution de l’UE Aucune donnée Adresse Via Reggio Emilia 39 20090 Segrate Milano Italie Voir sur la carte Coût total Aucune donnée
