Abstract: An engineered substrate comprises: a seed layer made of a first semiconductor material for growth of a solar cell; a support substrate comprising a base and a surface layer epitaxially grown on a first side of the base, the base and the surface layer made of a second semiconductor material; a direct bonding interface between the seed layer and the surface layer; wherein a doping concentration of the surface layer is higher than a predetermined value such that the electrical resistivity at the direct bonding interface is below 10 mOhm·cm2, preferably below 1 mOhm·cm2; and wherein a doping concentration of the base as well as the thickness of the engineered substrate are such that absorption of the engineered substrate is less than 20%, preferably less than 10%, and total area-normalized series resistance of the engineered substrate is less than 10 mOhm·cm2, preferably less than 1 mOhm·cm2.

Abstract: An engineered substrate comprises: a seed layer made of a first semiconductor material for growth of a solar cell; a support substrate comprising a base and a surface layer epitaxially grown on a first side of the base, the base and the surface layer made of a second semiconductor material; a direct bonding interface between the seed layer and the surface layer; wherein a doping concentration of the surface layer is higher than a predetermined value such that the electrical resistivity at the direct bonding interface is below 10 mOhm·cm2, preferably below 1 mOhm·cm2; and wherein a doping concentration of the base as well as the thickness of the engineered substrate are such that absorption of the engineered substrate is less than 20%, preferably less than 10%, and total area-normalized series resistance of the engineered substrate is less than 10 mOhm·cm2, preferably less than 1 mOhm·cm2.

Abstract: This disclosure relates to a solar cell assembly structure for supporting a concentrator photovoltaic cell comprising a semiconducting structure and a diode, wherein the semiconducting structure comprises a first semiconducting region at least a part of which for placing the concentrator photovoltaic cell structure, and a second semiconducting region for realizing the diode within or on the second semiconducting region and wherein the part of the first semiconducting region for placing the concentrator photovoltaic cell structure and the second semiconducting region are not vertically overlapping.

Abstract: The present disclosure relates to a method for the manufacture of a wafer by providing a doped layer on a semiconductor substrate; providing a first semiconductor layer on the doped layer; providing a buried oxide layer on the first semiconductor layer; and providing a second semiconductor layer on the buried oxide layer to form a wafer having a buried oxide layer and a doped layer beneath the buried oxide layer. The disclosure also relates to the wafer that is produced by the new method.

Abstract: The present invention relates to a method for the manufacture of a wafer by providing a doped layer on a semiconductor substrate; providing a first semiconductor layer on the doped layer; providing a buried oxide layer on the first semiconductor layer; and providing a second semiconductor layer on the buried oxide layer to form a wafer having a buried oxide layer and a doped layer beneath the buried oxide layer. The invention also relates to the wafer that is produced by the new method.

Abstract: A method for reducing roughness of an exposed surface of an insulator layer on a substrate, by depositing an insulator layer on a substrate wherein the insulator layer includes an exposed rough surface opposite the substrate, and then smoothing the exposed rough surface of the insulator layer by exposure to a gas plasma in a chamber. The chamber contains therein a gas at a pressure of greater than 0.25 Pa but less than 30 Pa, and the gas plasma is created using a radiofrequency generator applying to the insulator layer a power density greater than 0.6 W/cm2 but less than 10 W/cm2 for at least 10 seconds to less than 200 seconds. Substrate bonding and layer transfer may be carried out subsequently to transfer the thin layer of substrate and the insulator layer to a second substrate.

Abstract: A method for forming a semiconductor structure that includes a thin layer of semiconductor material on a receiver wafer is disclosed. The method includes removing a thickness of material from a donor wafer, which comprises a support substrate and an epitaxial layer, for surface preparation and transferring a portion of the epitaxial layer from the donor wafer to the receiver wafer. The thickness removed during the surface preparation is adapted to enable formation of a new semiconductor structure from the remaining epitaxial portion of the donor wafer.

Abstract: A method for forming a semiconductor structure that includes a thin layer of semiconductor material on a receiver wafer is disclosed. The method includes removing a thickness of material from a donor wafer, which comprises a support substrate and an epitaxial layer, for surface preparation and transferring a portion of the epitaxial layer from the donor wafer to the receiver wafer. The thickness removed during the surface preparation is adapted to enable formation of a new semiconductor structure from the remaining epitaxial portion of the donor wafer.

Abstract: The invention relates to a recyclable donor wafer that includes a substrate and a formed layer thereon, wherein the formed layer has a thickness sufficient to provide (a) at least two useful layers for detachment therefrom and (b) additional material that can be removed to planarize exposed surfaces of the useful layers prior to detachment from the donor wafer.

Abstract: The invention relates to a method of producing a film intended for applications in electronics, optics or optronics starting from an initial wafer, which includes a step of implanting atomic species through one of the faces of the wafer. This method includes forming a step of defined height around the periphery of the wafer, with the step having a mean thickness that is less than that of the wafer; and selectively implanting atomic species through a face of the wafer but not through the step to form an implanted zone at a defined implant depth with the film being defined between the face of the wafer and the implanted zone. The implantation of atomic species into the step can be prevented by forming a protective layer at least over the step or by masking the step. The invention also relates to a wafer obtainable by the method.

Abstract: A semiconductor heterostructure that includes a support substrate with a first in-plane lattice parameter, a buffer structure formed on the support substrate and having on top in a relaxed state a second in-plane lattice parameter, and a multi-layer stack of ungraded layers formed on the buffer structure. This semiconductor hetero-structure possess a lower surface roughness than other heterostructures. In the heterostructure, the ungraded layers are strained layers that comprise at least one strained smoothing layer of a semiconductor material having in a relaxed state a third in-plane lattice parameter which has a value between the first and the second lattice parameter.

Abstract: A method for manufacturing a semiconductor heterostructure by first manufacturing a donor wafer having a first substrate with a first in-plane lattice parameter, a spatially graded buffer layer having a second in-plane lattice parameter, and a strained smoothing layer of a semiconductor material having a third in-plane lattice parameter which has a value between that of the first and second lattice parameters. A top layer is formed on the ungraded layer a top layer of a semiconductor material having a top surface, optionally with a superficial layer present on the top surface and having a thickness that is equal to or smaller than 10 nanometers. Next, a handle wafer of a second substrate having an insulator layer thereon is bonded with the donor wafer in such way that (a) the insulator layer of the handle wafer is bonded directly onto the top surface of the top layer of the donor wafer, or (b) the insulator layer of the handle wafer is bonded onto the superficial layer.

Abstract: A method for reducing roughness of an exposed surface of an insulator layer on a substrate, by depositing an insulator layer on a substrate wherein the insulator layer includes an exposed rough surface opposite the substrate; treating the first substrate to form a zone of weakness beneath the insulator layer; and smoothing the exposed rough surface of the insulator layer by exposure to a gas plasma in a chamber. The chamber contains therein a gas at a pressure of greater than 0.25 Pa but less than 30 Pa, and the gas plasma is created using a radio frequency generator applying to the insulator layer a power density greater than 0.6 W/cm2 but less than 10 W/cm2 for at least 10 seconds to less than 200 seconds. Substrate bonding and layer transfer may be carried out subsequently to transfer the thin layer of substrate to the insulator layer and to a second substrate.

Abstract: A method for producing a semiconductor structure that includes at least one useful layer on a substrate.

Abstract: A donor wafer resulting from a method of recycling the wafer after detaching at least one useful layer. The donor wafer includes a substrate; a buffer structure on the substrate; a protective layer associated with the buffer structure; and a post detachment layer located above the buffer structure and presenting projections or rough portions on its surface. The protective layer prevents removal of the entire buffer structure when the post detachment layer is removed.

Abstract: The invention relates to a method of re-forming a useful layer on a donor wafer after taking off a useful layer formed of a material chosen from among semiconductor materials. The donor wafer includes in succession a substrate and a taking-off structure, the taking-off structure includes the taken-off useful layer before taking-off. The method includes a removal of material involving a portion of the donor wafer on the side where the useful layer has been taken off. The material is removed by mechanical means so as to preserve a portion of the taking-off structure to form at least one other useful layer which can be taken off after re-forming, without adding additional material to the wafer.

Abstract: The invention relates to a method of transferring useful layers from a donor wafer which includes a multi-layer structure on the surface of the donor wafer that has a thickness sufficient to form multiple useful layers for subsequent detachment. The layers may be formed of materials having sufficiently different properties such that they may be selectively removed. The layers of material may also include sub-layers that can be selectively removed from each other.

Abstract: A method for fabricating a semiconductor structure having a high-strained crystalline layer with a low crystal defect density is disclosed. The structure includes a substrate having a first material comprising germanium or a Group(III)-Group(V)-semiconductor or alloy thereof. In addition, a crystalline epitaxial first layer, comprising a graded buffer layer and a substantially relaxed layer, is provided. The buffer layer is sufficiently relaxed to provide relaxation of the substantially relaxed layer deposited thereon. A further layer may be provided on the first layer, and the transfer of at least the further layer is facilitated by providing a weakened zone in the first layer.

Abstract: A method for concurrently producing at least a pair of semiconductor structures that each include at least one useful layer on a substrate. The method includes providing an initial structure that includes a useful layer having a front face on a support substrate. Atomic species are implanted into the useful layer to a controlled mean implantation depth to form a zone of weakness within the useful layer that defines first and second useful layers. Next, a stiffening substrate is bonded to the front face of the initial structure. The first useful layer is then detached from the second useful layer along the zone of weakness to obtain a pair of semiconductor structures with a first structure including the stiffening substrate and the first useful layer and a second structure including the support substrate and the second useful layer. The structures obtained can be used in the fields of electronics, optoelectronics or optics.

Abstract: The invention provides a method of producing a structure of a thin layer of semiconductor material on a support substrate. The thin layer is obtained from a donor substrate and includes an upper layer of semiconductor material. The method includes forming on the upper layer a bonding layer of a material that accepts diffusion from an element of the material of the upper layer, bonding the donor substrate from the side on which the bonding layer is formed on the upper layer to the support substrate, and diffusing the element from the upper layer into the bonding layer to homogenize the concentration of the element in the bonding layer and the upper layer. The result is that the thin layer of the structure is joined by the bonding layer to the upper layer.