Abstract: The present disclosure provides methodologies for manufacturing high efficiency silicon photovoltaic devices using hydrogen passivation to improve performance. The processing techniques disclosed use tailored thermal processes, sometimes coupled with exposure to radiation to enable the use of cheaper silicon material to manufacture high efficiency photovoltaic devices.

Abstract: The present disclosure provides methodologies for manufacturing high efficiency silicon photovoltaic devices using hydrogen passivation to improve performance. The processing techniques disclosed use tailored thermal processes, sometimes coupled with exposure to radiation to enable the use of cheaper silicon material to manufacture high efficiency photovoltaic devices.

Abstract: A photovoltaic device includes a first semiconducting area having an N-doped silicon base and a second semiconducting area having a P-doped silicon base. The two semiconducting areas are configured to form a PN junction. The first semiconducting area is devoid of boron and includes a concentration of P-type doping impurities that is at least equal to 20% of the concentration of N-type doping impurities.

Abstract: A feedstock of semiconductor material is placed in a crucible. A closed sacrificial recipient containing a dopant material is placed in the crucible. The content of the crucible is melted resulting in incorporation of the dopant in the molten material bath. The temperature increase is performed under a reduced pressure.

Abstract: A feedstock of semiconductor material is placed in a crucible. A closed sacrificial recipient containing a dopant material is placed in the crucible. The content of the crucible is melted resulting in incorporation of the dopant in the molten material bath. The temperature increase is performed under a reduced pressure.

Abstract: The device for melting and purifying of a silicon feedstock comprises a crucible arranged inside a sealed chamber. A thermal gradient can be applied to the crucible by an arranged heat exchanger and a heating device. The device likewise comprises a device for reducing the pressure inside the chamber to a value lower than 10?2 mbar and a device for stirring the silicon in the crucible. The silicon feedstock successively undergoes degassing and pre-heating to atmospheric temperature, and then melting and low pressure, high temperature purification. Once the low-pressure purification step has been completed, directed crystallization is carried out.

Abstract: A temperature gradient is established in a crystallization crucible by means of a heat source and a cooling system. The cooling system comprises a heat exchanger and an adjustable additional heat source. The cooling system is preferably formed by an induction coil cooled by a coolant liquid circulating in the induction coil and by an electrically conductive induction susceptor positioned between the crucible and induction coil. The fabrication process comprises heating the crucible via the top and controlling heat extraction from the crucible downwards by means of the heat exchanger and by means of regulation of the adjustable additional heat source.

Abstract: A temperature gradient is established in a crystallization crucible by means of a heat source and a cooling system. The cooling system comprises a heat exchanger and an adjustable additional heat source. The cooling system is preferably formed by an induction coil cooled by a coolant liquid circulating in the induction coil and by an electrically conductive induction susceptor positioned between the crucible and induction coil. The fabrication process comprises heating the crucible via the top and controlling heat extraction from the crucible downwards by means of the heat exchanger and by means of regulation of the adjustable additional heat source.

Abstract: Production of photovoltaic grade crystalline silicon is achieved by crystallization of a molten silicon feedstock, the sum of the initial donor doping element and acceptor doping element concentrations whereof is greater than 0.1 ppma, and both the acceptor and donor doping element concentrations whereof are less than 25 ppma. At least a predefined quantity of a doping material having a segregation coefficient of less than 0.1 is added to the feedstock. This addition enables a crystallized silicon to be produced the difference between the donor and acceptor doping profiles whereof is comprised between 0.1 and 5 ppma over at least 50% of the solidified silicon. A silicon presenting a concentration of at least one of the dopants is greater than or equal to 5 ppma and a difference less than or equal to 5 ppma between these two types of dopant is integrated in a photovoltaic cell.

Abstract: The device for producing a sheet of crystalline material by directional solidification of a material in liquid phase composed of a crucible provided with a bottom, side walls and at least one horizontal outlet slot arranged on a bottom part of a side wall. On its external surface in immediate proximity to the slot, the crucible presents electromagnetic means for creating magnetic repulsion forces on the material in liquid phase, at least at the level of the slot. An alternating current with a frequency comprised between 10 kHz and 300 kHz flows through the electromagnetic means. To foster stirring of the material in liquid phase, a low frequency can be used in addition to the above frequencies.

Abstract: A temperature gradient is established in a crystallization crucible by means of a heat source and a cooling system. The cooling system comprises a heat exchanger and an adjustable additional heat source. The cooling system is preferably formed by an induction coil cooled by a coolant liquid circulating in the induction coil and by an electrically conductive induction susceptor positioned between the crucible and induction coil. The fabrication process comprises heating the crucible via the top and controlling heat extraction from the crucible downwards by means of the heat exchanger and by means of regulation of the adjustable additional heat source.

Abstract: The device comprises a crucible (1) having a bottom (2) and side walls (3). The crucible (1) comprises at least one lateral slit (4) arranged horizontally at a bottom part of the side walls (3). The lateral slit (4) presents a width of more than 50 mm and preferably comprised between 100 mm and 500 mm. The height (H) of the slit (4) is comprised between 50 and 1000 micrometers. The crystalline material is output from the crucible via the lateral slit (4) so as to form a crystalline ribbon (R). The method comprises a step of bringing a crystallization seed into contact with the material output via the lateral slit (4) and a horizontal displacement step of the ribbon (R).

Abstract: The bottom of the crucible has much greater thermal transfer properties, parallel to an axis substantially perpendicular to the bottom, than those of the side walls. The bottom and side walls are formed by materials having the same main chemical constituents. The bottom can be transparent to infrared radiation and the side walls opaque to infrared radiation. The bottom can be made of amorphous silica and the side walls of opaque quartz ceramic. The crucible can also be made of graphite. The device can comprise a graphite felt, arranged between the bottom of the crucible and cooling means, and compression means of the graphite felt. It is thus possible to define a temperature gradient comprised between 8° C./cm and 30° C./cm in the liquid phase.

Abstract: The photovoltaic module comprises front and rear plates. An organic seal is arranged between the plates and delineates a tight internal volume, kept at a pressure lower than atmospheric pressure, wherein the photovoltaic cells are arranged. The seal is an organic seal, for example of thermoplastic nature, for example of the polybutylene family. The production method comprises formation of a negative pressure by suction. The method can comprise sweeping by neutral gases, establishment of the negative pressure and sealing by compression. The method can also comprise partial sealing of the module so as to leave two openings in the seal, sweeping of the internal volume by neutral gases by means of the two openings, establishment of the negative pressure and closing of the openings.

Abstract: The photovoltaic module comprises front and rear plates. An organic seal is arranged between the plates and delineates a tight internal volume, kept at a pressure lower than atmospheric pressure, wherein the photovoltaic cells are arranged. The seal is an organic seal, for example of thermoplastic nature, for example of the polybutylene family. The production method comprises formation of a negative pressure by suction. The method can comprise sweeping by neutral gases, establishment of the negative pressure and sealing by compression. The method can also comprise partial sealing of the module so as to leave two openings in the seal, sweeping of the internal volume by neutral gases by means of the two openings, establishment of the negative pressure and closing of the openings.

Abstract: The bottom of the crucible has much greater thermal transfer properties, parallel to an axis substantially perpendicular to the bottom, than those of the side walls. The bottom and side walls are formed by materials having the same main chemical constituents. The bottom can be transparent to infrared radiation and the side walls opaque to infrared radiation. The bottom can be made of amorphous silica and the side walls of opaque quartz ceramic. The crucible can also be made of graphite. The device can comprise a graphite felt, arranged between the bottom of the crucible and cooling means, and compression means of the graphite felt. It is thus possible to define a temperature gradient comprised between 8° C./cm and 30° C./cm in the liquid phase.

Abstract: The solar cell in the semiconductor substrate includes at least a radiation receiving front surface and a second surface. The substrate includes a first region of one type of conductivity and a second region of the opposite conductivity type with at least a first part located adjacent to the front surface and a second part located adjacent to the second surface. The front surface includes conductive contacts to the second region and the second surface has separated contacts to the first region and to the second region. The contacts to the second region at the second surface are connected to the contacts at the front surface through a limited number of vias.