Abstract: A method of forming an epitaxially grown layer by forming a region of weakness in a support substrate to define a support portion and a remainder portion on opposite sides of the region of weakness, epitaxially growing an epitaxially grown layer on the support portion after forming the region of weakness but prior to detachment of the support portion from the remainder portion; bonding the epitaxially grown layer to an acceptor substrate before detaching the remainder portion from the support portion; and detaching the remainder portion from the support portion at the region of weakness. The epitaxially grown layer may be removed from the support portion as a free-standing structure.

Abstract: The present invention relates to a method for the formation of an at least partially relaxed strained material layer, the method comprising the steps of providing a seed substrate; patterning the seed substrate; growing a strained material layer on the patterned seed substrate; transferring the strained material layer from the patterned seed substrate to an intermediate substrate; and at least partially relaxing the strained material layer by a heat treatment.

Abstract: A method of fabricating a device by providing an auxiliary substrate having a metal nitride layer disposed thereon where the nitride layer has a nitrogen face and an opposite face and a dislocation density that is less than about 106, with the nitrogen face of the nitride layer facing the auxiliary substrate; depositing at least one epitaxial nitride layer on the exposed opposite face of the nitride layer of the structure; depositing a further metal layer over at least a portion of the epitaxial nitride layer(s); bonding a final substrate on the deposited metal layer; and removing the auxiliary substrate to form the device from the final substrate and deposited layers. Preferably, the device that is formed includes a LED or laser.

Abstract: The present invention provides methods for forming at least partially relaxed strained material layers on a target substrate. The methods include forming islands of the strained material layer on an intermediate substrate, at least partially relaxing the strained material islands by a first heat treatment, and transferring the at least partially relaxed strained material islands to the target substrate. The at least partial relaxation is facilitated by the presence of low-viscosity or compliant layers adjacent to the strained material layer. The invention also provides semiconductor structures having an at least partially relaxed strained material layer, and semiconductor devices fabricated using an at least partially relaxed strained material layer.

Abstract: The present invention provides methods for forming at least partially relaxed strained material layers on a target substrate. The methods include forming islands of the strained material layer on an intermediate substrate, at least partially relaxing the strained material islands by a first heat treatment, and transferring the at least partially relaxed strained material islands to the target substrate. The at least partial relaxation is facilitated by the presence of low-viscosity or compliant layers adjacent to the strained material layer. The invention also provides semiconductor structures having an at least partially relaxed strained material layer, and semiconductor devices fabricated using an at least partially relaxed strained material layer.

Abstract: The present invention relates to a method for relaxing a strained material layer by providing a strained material layer and a low-viscosity layer formed on a first face of the strained material layer; forming a stiffening layer on at least one part of a second face of the strained material layer opposite to the first face thereby forming a multilayer stack; and subjecting the multilayer stack to a heat treatment thereby at least partially relaxing the strained material layer.

Abstract: A method for making substrates for use in optics, electronics, or opto-electronics. The method may include transferring a seed layer onto a receiving substrate and depositing a useful layer onto the seed layer. The thermal expansion coefficient of the receiving support may be identical to or slightly larger than the thermal expansion coefficient of the useful layer and the thermal expansion coefficient of the seed layer may be substantially equal to the thermal expansion coefficient of the receiving support. Preferably, the nucleation layer and the intermediate support have substantially the same chemical composition.

Abstract: A method for making substrates for use in optics, electronics, or opto-electronics. The method may include transferring a seed layer onto a receiving substrate and depositing a useful layer onto the seed layer. The thermal expansion coefficient of the receiving support may be identical to or slightly larger than the thermal expansion coefficient of the useful layer and the thermal expansion coefficient of the seed layer may be substantially equal to the thermal expansion coefficient of the receiving support. Preferably, the nucleation layer and the intermediate support have substantially the same chemical composition.

Abstract: A method for making substrates for use in optics, electronics, or opto-electronics. The method may include transferring a seed layer onto a receiving support and depositing a useful layer onto the seed layer. The thermal expansion coefficient of the receiving support may be identical to or slightly larger than the thermal expansion coefficient of the useful layer and the thermal expansion coefficient of the seed layer may be substantially equal to the thermal expansion coefficient of the receiving support. Preferably, the nucleation layer and the intermediate support have substantially the same chemical composition.

Abstract: A method of fabricating a composite structure that has at least one thin film bonded to a support substrate and a bonding layer of oxide formed by deposition between the support substrate and the thin film. The thin film and the support substrate have a mean thermal expansion coefficient of 7×10?6 K?1 or more. The bonding layer of oxide is formed by low pressure chemical vapor deposition (LPCVD) of a layer of oxide on the bonding face of the support substrate or on the bonding face of the thin film. The thin film has a thickness of 5 micrometers or less while the thickness of the layer of oxide is equal to or greater than the thickness of the thin film.

Abstract: A method of fabricating materials by epitaxy by epitaxially growing at least one layer of a material upon a composite structure that has at least one thin film bonded to a support substrate and a bonding layer of oxide formed by deposition between the support substrate and the thin film. The thin film and the support substrate have a mean thermal expansion coefficient of 7×10?6 K?1 or more. The bonding layer is formed by low pressure chemical vapor deposition (LPCVD) of a layer of silicon oxide on the bonding face of the support substrate or on the bonding face of the thin film. The thin film has a thickness of 5 micrometers or less while the thickness of the layer of oxide is equal to or greater than the thickness of the thin film. The method also includes a heat treatment carried out at a temperature that is higher than the temperature for deposition of the layer of oxide of silicon and for a predetermined period.

Abstract: Methods of fabricating relaxed layers of semiconductor materials include forming structures of a semiconductor material overlying a layer of a compliant material, and subsequently altering a viscosity of the compliant material to reduce strain within the semiconductor material. The compliant material may be reflowed during deposition of a second layer of semiconductor material. The compliant material may be selected so that, as the second layer of semiconductor material is deposited, a viscosity of the compliant material is altered imparting relaxation of the structures. In some embodiments, the layer of semiconductor material may comprise a III-V type semiconductor material, such as, for example, indium gallium nitride. Methods of fabricating semiconductor structures and devices are also disclosed. Novel intermediate structures are formed during such methods.

Abstract: The present invention provides, in part, methods producing multilayer semiconductor structures having one or more at least partially relaxed strained layers, where the strained layer is at least partially relaxed by annealing. In particular, the invention forms diffusion barriers that prevent diffusion of contaminants during annealing. The invention also includes embodiments where the at least partially relaxed strained layer is patterned into islands by etching trenches and the like. The invention also provides semiconductor structures resulting from these methods, and further, provides such structures where the semiconductor materials are suitable for application to LED devices, laser devices, photovoltaic devices, and other optoelectronic devices.

Abstract: A method of fabricating a thin film from a substrate includes implantation into the substrate, for example made of silicon, of ions of a non-gaseous species, for example gallium, the implantation conditions and this species being chosen, according to the material of the substrate, so as to allow the formation of precipitates confined in a certain depth, distributed within a layer, these precipitates being made of a solid phase having a melting point below that of the substrate. The method optionally further including intimate contacting of this face of the substrate with a stiffener, and detachment of a thin film by fracturing the substrate at the layer of precipitates by applying a mechanical and/or chemical detachment stress under conditions in which the precipitates are in the liquid phase.

Abstract: The present invention provides, in part, methods producing multilayer semiconductor structures having one or more at least partially relaxed strained layers, where the strained layer is at least partially relaxed by annealing. In particular, the invention forms diffusion barriers that prevent diffusion of contaminants during annealing. The invention also includes embodiments where the at least partially relaxed strained layer is patterned into islands by etching trenches and the like. The invention also provides semiconductor structures resulting from these methods, and further, provides such structures where the semiconductor materials are suitable for application to LED devices, laser devices, photovoltaic devices, and other optoelectronic devices.

Abstract: The present invention provides methods for forming at least partially relaxed strained material layers on a target substrate. The methods include forming islands of the strained material layer on an intermediate substrate, at least partially relaxing the strained material islands by a first heat treatment, and transferring the at least partially relaxed strained material islands to the target substrate. The at least partial relaxation is facilitated by the presence of low-viscosity or compliant layers adjacent to the strained material layer. The invention also provides semiconductor structures having an at least partially relaxed strained material layer, and semiconductor devices fabricated using an at least partially relaxed strained material layer.

Abstract: The invention relates to a process for fabricating a heterostructure. This process is noteworthy in that it comprises the following steps: a) a strained crystalline thin film is deposited on, or transferred onto, an intermediate substrate; b) a strain relaxation layer, made of crystalline material capable of being plastically deformed by a heat treatment at a relaxation temperature, at which the material constituting the thin film deforms by elastic deformation is deposited on the thin film; c) the thin film and the relaxation layer are transferred onto a substrate; and d) a thermal budget is applied at at least the relaxation temperature, so as to cause the plastic deformation of the relaxation layer and the at least partial relaxation of the thin film by elastic deformation, and thus to obtain the final heterostructure.

Abstract: The invention relates to a process for making a GaN substrate (60), characterized in that it comprises the following steps: (a) transferring a first monocrystal GaN layer (50) onto a supporting substrate (40); (b) applying crystal growth for a second monocrystal GaN layer on the first layer (50); the first and second GaN layers thereby forming together said GaN substrate (60), said GaN substrate (60) having a thickness of at least 10 micrometers, (c) removing at least one portion of the supporting substrate (40).

Abstract: An efficient method of fabricating a high-quality heteroepitaxial microstructure having a smooth surface. The method includes detaching a layer from a base structure to provide a carrier substrate having a detached surface, and then forming a heteroepitaxial microstructure on the detached surface of the carrier substrate by depositing an epitaxial layer on the detached surface of a carrier substrate. Also included is a heteroepitaxial microstructure fabricated from such method.

Abstract: A method of forming an epitaxially grown layer, preferably by providing a region of weakness in a support substrate and transferring a nucleation portion to the support substrate by bonding. A remainder portion of the support substrate is detached at the region of weakness and an epitaxial layer is grown on the nucleation portion. The remainder portion is separated or otherwise removed from the support portion.