Objetivo
Material deposition techniques have been developed to produce amorphous silicon modules with sizes up to 1 x 0.6 m and production problems such as high throughput and machine cleaning have been solved.
Studies on the physics of amorphous silicon devices have been conducted with a strong emphasis on stability.
Module integration on a monolithic glass substrate was achieved by a set of flexible techniques compatible with any module pattern. All losses related to the making of a module were introduced into a model allowing size optimization. All assumptions and predictions of the model were confirmed by a systematic scanning procedure of a series of 30 x 30 cm modules.
Studies on plasma and deposition science have included:
comparison of the many deposition techniques;
basic research on deposition;
large machine development;
the design of a 30 x 30 cm machine;
design of production machines.
Studies on pin development have included:
electrode development;
control of punctual defects;
photovoltaic performances;
trimethyl baron as a new doping gas.
Studies on module technology have included:
module design;
interconnection technology.
FOR THE FIRST 3 MONTHS OF THE CONTRACT, EMPHASIS WAS PUT ON THE IMPROVEMENT OF THE REAR CONTACT IN THE CELL STRUCTURE AND, INDEPENDANTLY, ON THE DEPOSITION OF VERY LARGE SURFACES. A LARGE CHAMBER WAS BUILT, IT ALLOWS SIMULTANEOUS DEPOSITION ON TWO 60 X 110 CM2 SUBSTRATE. SYSTEMATIC ANALYSIS OF THE DEPOSITION UNIFORMITY HAS DEMONSTRATED THAT THE FINITE FREE SPACE WAVE LENGHT OF THE 13,5 MHZ DRIVING FREQUENCY SETS A LIMIT ON UNIFORMITY FOR VERY LARGE SUBSTRATE DUE TO THE APPEARANCE OF A STANDING WAVE PATTERN. A GOOD UNIFORMITY WAS RECOVERED BY USING A LOWER FREQUENCY GENERATOR (5MHZ). FOR THE DEVELOPMENT OF THE INTERFERENCE MIRROR AT THE REAR ELECTRODE, A REACTIVE SPUTTERING PROCESS WAS OPTIMIZED FOR DEPOSITION OF SNO2 FROM A METALLIC TIN MAGNETRON CATHODE (MRC) WITH A SPECIAL EMPHASIS ON MATERIAL UNIFORMITY ON THE 30 X 30 CM2 SUBSTRATE. DOPING BY OXYGEN VACANCIES AND ANTIMONY WERE TESTED. THIS SNO2 EXTRA LAYER WAS DEMONSTRATED TO BE AN EXCELLENT REFLECTIVITY BOOSTER FOR RED LIGHT. IT WILL BE TESTED LATER WITHIN A TEXTURED PHOTODIODE FOR LIGHT TRAPPING. ANOTHER POTENTIAL BENEFIT FROM THIS SNO2 LAYER COULD BE BUFFERING OF PIN HOLE IF IT COULD BE MADE RESISTIVE ENOUGH.
HOWEVER PRELIMINARY RESULTS INDICATE DAMAGING NON OHMIC BEHAVIOUR FROM THE UNDOPED SNO2 LAYER.
Ámbito científico
Programa(s)
Tema(s)
Data not availableConvocatoria de propuestas
Data not availableRégimen de financiación
CSC - Cost-sharing contractsCoordinador
91124 Palaiseau
Francia