Abstract: A substrate characterised in that it is at least partially surface-coated with a coating containing at least one so-called “barrier” layer having silica and one or more material(s) X selected from among SiC, Si, Si3N4, in which layer the amount of X varies between 25-wt. % and 50.-wt. % in relation to the total weight of the barrier layer, the barrier layer being formed by grains of one or more materials X covered at least partially in a silica shell, and the barrier layer being in direct contact with the substrate.

Abstract: A substrate, in particular intended for contact with liquid silicon, wherein it is at least partially surface-coated with a multilayer coating formed by: at least one layer, known as the adhesion layer, contiguous with the substrate, having an open porosity of at least 30%, and formed of a material comprising silica and silicon nitride, said material having a silica content of between 10 wt.-% and 55 wt.-% in relation to the total weight thereof; and a layer different from the adhesion layer, known as the release layer, located on the surface of the adhesion layer and formed of a material including silica and silicon nitride, said material having a silica content of between 2 wt.-% and 10 wt.-% in relation to the total weight thereof.

Abstract: A substrate, in particular intended for contact with liquid silicon, wherein it is at least partially surface-coated with a multilayer coating formed by: at least one layer, known as the adhesion layer, contiguous with the substrate, having an open porosity of at least 30%, and formed of a material comprising silica and silicon nitride, said material having a silica content of between 10 wt.-% and 55 wt.-% in relation to the total weight thereof; and a layer different from the adhesion layer, known as the release layer, located on the surface of the adhesion layer and formed of a material including silica and silicon nitride, said material having a silica content of between 2 wt.-% and 10 wt.-% in relation to the total weight thereof.

Abstract: A substrate characterised in that it is at least partially surface-coated with a coating containing at least one so-called “barrier” layer having silica and one or more material(s) X selected from among SiC, Si, Si3N4, in which layer the amount of X varies between 25-wt. % and 50.-wt. % in relation to the total weight of the barrier layer, the barrier layer being formed by grains of one or more materials X covered at least partially in a silica shell, and the barrier layer being in direct contact with the substrate.

Abstract: The present invention relates to novel materials intended for being contacted with liquid silicon and having a multilayer architecture, the intermediate layer of which is formed by a silicon carbide matrix containing at least one carbon nodule. The invention also relates to the method for preparing said materials.

Abstract: The present invention relates to a method of assembling carbon parts using a braze based on silicon carbide. The invention also relates to the parts assembled using such a method.

Abstract: The present invention relates to a method for forming, on the surface of one of the sides of a silicon substrate, a fibrous layer having a mean lattice pitch of no more than 2 ?m, without requiring soaking. The invention also relates to devices, in particular photovoltaic cells, comprising a silicon substrate produced by means of such a method.

Abstract: The present invention relates to novel materials intended for being contacted with liquid silicon and having a multilayer architecture, the intermediate layer of which is formed by a silicon carbide matrix containing at least one carbon nodule. The invention also relates to the method for preparing said materials.

Abstract: A silicon wafer for a photovoltaic cell is produced by a debinding step of a self-supported film formed of at least one main thin layer comprising at least 50% volume of silicon particles, devoid of silicon oxide and encapsulated in a polymer matrix protecting them against oxidation, followed by a sintering step to form the silicon wafer.

Abstract: The present invention relates to a process for forming a nonstick coating, said coating being formed from grains of silicon carbide, which are surface-coated with a layer of silicon oxide. It also targets the materials having a coating formed by this process.

Abstract: The present invention relates to a method of assembling carbon parts using a braze based on silicon carbide. The invention also relates to the parts assembled using such a method.

Abstract: The invention relates to a method for preparing a self-supporting crystallized silicon thin film having a grain size of more than 1 mm. The invention also relates to the use of said method for preparing self-supporting silicon bands and to the bands thus obtained.

Abstract: The method enables metallurgical silicon to be purified by directional solidification to obtain solar or photovoltaic grade silicon. A crystallization step uses at least one silicon seed, preference of solar grade or even microelectronic grade, having for example a purity substantially equal to or greater than a predetermined purity of the solar-grade silicon. The silicon seed which covers the bottom of the crucible can come from a previous crystallization or be formed by a silicon wafer. The use of a single-crystal or textured multi-crystal seed enables crystallographic orientation of the solar-grade silicon. An intermediate layer of solid metallurgical silicon can be arranged on the silicon seed and a metallurgical silicon feedstock is arranged on the intermediate layer.

Abstract: The method enables metallurgical silicon to be purified by directional solidification to obtain solar or photovoltaic grade silicone. A crystallization step uses at least one silicon seed, preference of solar grade or even microelectronic grade, having for example a purity substantially equal to or greater than a predetermined purity of the solar-grade silicon. The silicon seed which covers the bottom of the crucible can come from a previous crystallization or be formed by a silicon wafer. The use of a single-crystal or textured multi-crystal seed enables crystallographic orientation of the solar-grade silicon. An intermediate layer of solid metallurgical silicon can be arranged on the silicon seed and a metallurgical silicon feedstock is arranged on the intermediate layer.

Abstract: Self-supported film and silicon wafer obtained by sintering. A silicon wafer for a photovoltaic cell is produced by a debinding step of a self-supported film formed of at least one main thin layer comprising at least 50% volume of silicon particles, devoid of silicon oxide and encapsulated in a polymer matrix protecting them against oxidation, followed by a sintering step to form the silicon wafer.

Abstract: Wafers of semi-conducting material are formed by moulding and directional crystallization from a liquid mass of this material. A seed, situated at the bottom of the crucible, presents an orientation along non-dense crystallographic planes. The mould is filled with the molten semi-conducting material by means of a piston or by creation of a pressure difference in the device. The mould is preferably coated with a non-wettable anti-adhesive deposit.

Abstract: The invention relates to a thin film having a thickness of less than 10 nm, made of oxidizable semi-conductor material and patterned in the form of patterns. To prevent the dewetting phenomenon of said patterns, lateral oxidized zones are arranged at the periphery of each pattern of the thin film so as to form an anchoring. This anchoring can be achieved by forming an oxide layer over the whole of the thin film and then depositing a nitride layer. Then the nitride and oxide layers and the thin film are patterned and the thin film is laterally oxidized so that each pattern of the thin film comprises, at the periphery thereof, an oxidized zone of predetermined width. The nitride and oxide layers are then removed so as to release the patterns oxidized at their periphery.

Abstract: Wafers of semi-conducting material are formed by moulding and directional crystallization from a liquid mass of this material. A seed, situated at the bottom of the crucible, presents an orientation along non-dense crystallographic planes. The mould is filled with the molten semi-conducting material by means of a piston or by creation of a pressure difference in the device. The mould is preferably coated with a non-wettable anti-adhesive deposit.

Abstract: The invention relates to a thin film having a thickness of less than 10 nm, made of oxidizable semi-conductor material and patterned in the form of patterns. To prevent the dewetting phenomenon of said patterns, lateral oxidized zones are arranged at the periphery of each pattern of the thin film so as to form an anchoring. This anchoring can be achieved by forming an oxide layer over the whole of the thin film and then depositing a nitride layer. Then the nitride and oxide layers and the thin film are patterned and the thin film is laterally oxidized so that each pattern of the thin film comprises, at the periphery thereof, an oxidized zone of predetermined width. The nitride and oxide layers are then removed so as to release the patterns oxidized at their periphery.