Abstract: Substrates for microelectronic radiofrequency devices may include a substrate comprising a semiconductor material. Trenches may be located in an upper surface of the substrate, at least some of the trenches including a filler material located within the respective trench. A resistivity of the filler material may be 10 kOhms·cm or greater. A piezoelectric material may be located on or above the upper surface of the substrate. Methods of making substrates for microelectronic radiofrequency devices may involve forming trenches in an upper surface of a substrate including a semiconductor material. A filler material may be placed in at least some of the trenches, and a piezoelectric material may be placed on or above the upper surface of the substrate.

Abstract: A method for producing a semiconductor structure comprises: a) providing a working layer of a semiconductor material; b) providing a carrier substrate of a semiconductor material; c) depositing a thin film of a semiconductor material different from that or those of the working layer and the carrier substrate on a free face to be joined of the working layer and/or the carrier substrate; d) directly joining the free faces of the working layer and the carrier substrate, e) annealing the joined structure at an elevated temperature to bring about segmentation of the encapsulated thin film and form a semiconductor structure comprising an interface region between the working layer and the carrier substrate, the interface region comprising: —regions of direct contact between the working layer and the carrier substrate; and —agglomerates comprising the semiconductor material of the thin film adjacent the regions of direct contact.

Abstract: The present disclosure relates to a method for mechanically separating layers, in particular in a double layer transfer process. The present disclosure relates more in particular to a method for mechanically separating layers, comprising the steps of providing a semiconductor compound comprising a layer of a handle substrate and an active layer with a front main side and a back main side opposite the front main side, wherein the layer of the handle substrate is attached to the front main side of the active layer, then providing a layer of a carrier substrate onto the back main side of the active layer, and then initiating mechanical separation of the layer of the handle substrate, wherein the layer of the handle substrate and the layer of the carrier substrate are provided with a substantially symmetrical mechanical structure.

Abstract: A substrate for a surface acoustic wave device or bulk acoustic wave device, comprising a support substrate and an piezoelectric layer on the support substrate, wherein the support substrate comprises a semiconductor layer on a stiffening substrate having a coefficient of thermal expansion that is closer to the coefficient of thermal expansion of the material of the piezoelectric layer than that of silicon, the semiconductor layer being arranged between the piezoelectric layer and the stiffening substrate.

Abstract: The present invention relates to a heterostructure, in particular, a piezoelectric structure, comprising a cover layer, in particular, a layer of piezoelectric material, the material of the cover layer having a first coefficient of thermal expansion, assembled to a support substrate, the support substrate having a second coefficient of thermal expansion substantially different from the first coefficient of thermal expansion, at an interface wherein the cover layer comprises at least a recess extending from the interface into the cover layer, and its method of fabrication.

Abstract: The present disclosure relates to a method for mechanically separating layers, in particular in a double layer transfer process. The present disclosure relates more in particular to a method for mechanically separating layers, comprising the steps of providing a semiconductor compound comprising a layer of a handle substrate and an active layer with a front main side and a back main side opposite the front main side, wherein the layer of the handle substrate is attached to the front main side of the active layer, then providing a layer of a carrier substrate onto the back main side of the active layer, and then initiating mechanical separation of the layer of the handle substrate, wherein the layer of the handle substrate and the layer of the carrier substrate are provided with a substantially symmetrical mechanical structure.

Abstract: A method of producing a composite structure comprising a thin layer of monocrystalline silicon carbide arranged on a carrier substrate of silicon carbide comprises: a) a step of provision of an initial substrate of monocrystalline silicon carbide, b) a step of epitaxial growth of a donor layer of monocrystalline silicon carbide on the initial substrate, to form a donor substrate, c) a step of ion implantation of light species into the donor layer, to form a buried brittle plane delimiting the thin layer, d) a step of formation of a carrier substrate of silicon carbide on the free surface of the donor layer, comprising a deposition at a temperature of between 400° C. and 1100° C., e) a step of separation along the buried brittle plane, to form the composite structure and the remainder of the donor substrate, and f) a step of chemical-mechanical treatment(s) of the composite structure.

Abstract: A production method for a surface acoustic wave device comprises the following steps: a step of providing a piezoelectric substrate comprising a transducer arranged on the main front face; a step of depositing a dielectric encapsulation layer on the main front face of the piezoelectric substrate and on the transducer; and a step of assembling the dielectric encapsulation layer with the main front face of a support substrate having a coefficient of thermal expansion less than that of the piezoelectric substrate. In additional embodiments, a surface acoustic wave device comprises a layer of piezoelectric material equipped with a transducer on a main front face, arranged on a substrate support of which the coefficient of thermal expansion is less than that of the piezoelectric material. The transducer is arranged in a dielectric encapsulation layer, between the layer of piezoelectric material and the support substrate.

Abstract: A substrate for a surface acoustic wave device or bulk acoustic wave device, comprising a support substrate and an piezoelectric layer on the support substrate, wherein the support substrate comprises a semiconductor layer on a stiffening substrate having a coefficient of thermal expansion that is closer to the coefficient of thermal expansion of the material of the piezoelectric layer than that of silicon, the semiconductor layer being arranged between the piezoelectric layer and the stiffening substrate.

Abstract: A composite substrate includes a final substrate, and a piezoelectric material directly molecularly bonded to the final substrate at a first interface. The piezoelectric material comprises an epitaxial layer, but does not comprise a seed layer. Additional composite substrates include a final substrate, and a piezoelectric material directly molecularly bonded to the final substrate at a first interface. The piezoelectric material comprises an epitaxial layer. The composite substrate further includes a seed layer on which the piezoelectric material has been epitaxially grown. The seed layer is disposed on a side of the epitaxial layer opposite the final substrate. An acoustic wave device comprises such a composite substrate with at least one electrode on a surface of the piezoelectric layer opposite the substrate.

Abstract: A method for manufacturing a composite structure comprising a thin layer made of monocrystalline silicon carbide arranged on a carrier substrate made of silicon carbide, the method comprising: a) a step of providing a donor substrate made of monocrystalline SiC, the donor substrate comprising a donor layer produced by epitaxial growth on an initial substrate, the donor layer exhibiting a density of crystal defects that is lower than that of the initial substrate; b) a step of ion implantation of light species into the donor layer, in order to form a buried brittle plane delimiting the thin layer between the buried brittle plane and a free face of the donor layer; c) a succession of n steps of formation of carrier layers, with n greater than or equal to 2, the n carrier layers being arranged on the donor layer successively on one another and forming the carrier substrate, each step of formation comprising a chemical vapor deposition, at a temperature of between 400° C. and 1100° C.

Abstract: A production method for a surface acoustic wave device comprises the following steps: a step of providing a piezoelectric substrate comprising a transducer arranged on the main front face; a step of depositing a dielectric encapsulation layer on the main front face of the piezoelectric substrate and on the transducer; and a step of assembling the dielectric encapsulation layer with the main front face of a support substrate having a coefficient of thermal expansion less than that of the piezoelectric substrate. In additional embodiments, a surface acoustic wave device comprises a layer of piezoelectric material equipped with a transducer on a main front face, arranged on a substrate support of which the coefficient of thermal expansion is less than that of the piezoelectric material. The transducer is arranged in a dielectric encapsulation layer, between the layer of piezoelectric material and the support substrate.

Abstract: The present invention relates to a heterostructure, in particular, a piezoelectric structure, comprising a cover layer, in particular, a layer of piezoelectric material, the material of the cover layer having a first coefficient of thermal expansion, assembled to a support substrate, the support substrate having a second coefficient of thermal expansion substantially different from the first coefficient of thermal expansion, at an interface wherein the cover layer comprises at least a recess extending from the interface into the cover layer, and its method of fabrication.

Abstract: A method for manufacturing a monocrystalline piezoelectric material layer includes providing a donor substrate made of the piezoelectric material, providing a receiving substrate, transferring a so-called “seed layer” of the donor substrate onto the receiving substrate, and using epitaxy of the piezoelectric material on the seed layer until the desired thickness for the monocrystalline piezoelectric layer is obtained.

Abstract: The present invention relates to a heterostructure, in particular, a piezoelectric structure, comprising a cover layer, in particular, a layer of piezoelectric material, the material of the cover layer having a first coefficient of thermal expansion, assembled to a support substrate, the support substrate having a second coefficient of thermal expansion substantially different from the first coefficient of thermal expansion, at an interface wherein the cover layer comprises at least a recess extending from the interface into the cover layer, and its method of fabrication.

Abstract: Substrates for microelectronic radiofrequency devices may include a substrate comprising a semiconductor material. Trenches may be located in an upper surface of the substrate, at least some of the trenches including a filler material located within the respective trench. A resistivity of the filler material may be 10 kOhms·cm or greater. A piezoelectric material may be located on or above the upper surface of the substrate. Methods of making substrates for microelectronic radiofrequency devices may involve forming trenches in an upper surface of a substrate including a semiconductor material. A filler material may be placed in at least some of the trenches, and a piezoelectric material may be placed on or above the upper surface of the substrate.

Abstract: Substrates for microelectronic radiofrequency devices may include a substrate comprising a semiconductor material. Trenches may be located in an upper surface of the substrate, at least some of the trenches including a filler material located within the respective trench. A resistivity of the filler material may be 10 kOhms·cm or greater. A piezoelectric material may be located on or above the upper surface of the substrate. Methods of making substrates for microelectronic radiofrequency devices may involve forming trenches in an upper surface of a substrate including a semiconductor material. A filler material may be placed in at least some of the trenches, and a piezoelectric material may be placed on or above the upper surface of the substrate.

Abstract: A method for manufacturing a structure comprising a first substrate comprising at least one electronic component likely to be damaged by a temperature higher than 400° C. and a semiconductor layer extending on the first substrate comprises: (a) providing a first bonding metal layer on the first substrate, (b) providing a second substrate comprising successively: a semiconductor base substrate, a stack of a plurality of semiconductor epitaxial layers, a layer of SixGe1-x, with 0?x?1 being located at the surface of said stack opposite to the base substrate, and a second bonding metal layer, (c) bonding the first substrate and the second substrate through the first and second bonding metal layers at a temperature lower than or equal to 400° C., and (d) removing a part of the second substrate so as to transfer the layer of SixGe1-x on the first substrate using a selective etching process.

Abstract: The disclosure relates to a process for locating devices, the process comprising the following steps: a) providing a carrier substrate comprising: a device layer; and alignment marks; b) providing a donor substrate; c) forming a weak zone in the donor substrate, the weak zone delimiting a useful layer; d) assembling the donor substrate and the carrier substrate; and e) fracturing the donor substrate in the weak zone so as to transfer the useful layer to the device layer; wherein the alignment marks are placed in cavities formed in the device layer, the cavities having an aperture flush with the free surface of the device layer.

Abstract: Substrates for microelectronic radiofrequency devices may include a substrate comprising a semiconductor material. Trenches may be located in an upper surface of the substrate, at least some of the trenches including a filler material located within the respective trench. A resistivity of the filler material may be 10 kOhms·cm or greater. A piezoelectric material may be located on or above the upper surface of the substrate. Methods of making substrates for microelectronic radiofrequency devices may involve forming trenches in an upper surface of a substrate including a semiconductor material. A filler material may be placed in at least some of the trenches, and a piezoelectric material may be placed on or above the upper surface of the substrate.