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  • H10D62/83—Semiconductor bodies, or regions thereof, of devices having potential barriers characterised by the materials being Group IV materials, e.g. B-doped Si or undoped Ge
  • H10D62/832—Semiconductor bodies, or regions thereof, of devices having potential barriers characterised by the materials being Group IV materials, e.g. B-doped Si or undoped Ge being Group IV materials comprising two or more elements, e.g. SiGe
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  • H10P14/34—Deposited materials, e.g. layers
  • H10P14/3402—Deposited materials, e.g. layers characterised by the chemical composition
  • H10P14/3404—Deposited materials, e.g. layers characterised by the chemical composition being Group IVA materials
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  • H10P14/20—Formation of materials, e.g. in the shape of layers or pillars of semiconductor materials
  • H10P14/34—Deposited materials, e.g. layers
  • H10P14/3438—Doping during depositing
  • H10P14/3441—Conductivity type
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  • H10P14/34—Deposited materials, e.g. layers
  • H10P14/3438—Doping during depositing
  • H10P14/3441—Conductivity type
  • H10P14/3444—P-type

Definitions

• the invention relates to a method for manufacturing a semiconductor structure comprising a support substrate of polycrystalline silicon carbide and an active layer of monocrystalline silicon carbide, as well as such a structure and an electronic device comprising such a structure, in particular for power applications or radio frequency applications.
• Silicon carbide is a material of interest in microelectronics, in particular for the fabrication of substrates for electronic devices intended for power applications.
• microelectronic devices comprise an active layer of single-crystal SiC, in or on which transistors and other electronic components adapted to perform the required functions are formed.
• the active layer is arranged on a polycrystalline SiC support substrate doped to have good electrical conductivity. Indeed, in these devices, the electric current applied to the transistors and other electric components of the active layer passes through the substrate, in the direction of its rear face, which is the face opposite the active layer.
• the formation of a semiconductor structure comprising the active layer and the support substrate can be carried out by the Smart CutTM process.
• the Smart CutTM process by implantation of atomic species in a monocrystalline SiC donor substrate, an embrittlement zone delimiting the active layer is formed, the donor substrate is bonded to a polycrystalline SiC support substrate, then the donor substrate is detached along the embrittlement zone so as to transfer the active layer onto the support substrate.
• the detachment can be initiated by a mechanical action, a heat treatment or any other suitable means, said means possibly being able to be combined.
• SiC has several polytypes, i.e. different crystalline structures.
• the main polytypes used in the field of microelectronics are the 3C polytype, of cubic structure, and the 4H and 6H polytypes, of hexagonal structure. These polytypes differ in particular by their lattice parameter, by their electronic band diagrams and by their coefficient of thermal expansion.
• polycrystalline SiC substrates are commercially available in the 3C form. Indeed, this polytype can be obtained by chemical vapor deposition on a seed substrate, generally made of graphite, at a relatively low temperature, that is to say typically less than or equal to 1400° C., so that the manufacturing process is relatively energy efficient.
• single-crystal SiC substrates are commercially available, in dimensions useful in industry, that is to say typically of the order of 150 to 200 mm in diameter, with a hexagonal structure, of the 4H or 6H.
• the assembly of an active layer of type 4H polycrystalline SiC and a support substrate of polycrystalline SiC involves the formation of an interface with two types of discontinuities: a discontinuity in terms of crystalline quality (monocrystalline / polycrystalline ) and a discontinuity in terms of crystal structure (hexagonal/cubic).
• the difference in thermal expansion coefficient can generate a deformation of the structure when it is subjected to a high thermal budget.
• Such a thermal budget can be applied to the structure during annealing intended to reinforce the bonding interface.
• the known methods do not allow direct bonding of the donor substrate on the support substrate, and require the use of a bonding layer, for example of doped silicon. Bonding is then frequently followed by stabilization annealing carried out at a temperature of around 1700°C.
• a high thermal budget typically between 1500 and 2000°C, can also be applied during a subsequent phase of manufacturing the electronic device, for example when epitaxy is carried out on the active layer to form other parts of the electronic device. , or during a heat treatment for activating dopants.
• the deformation due to the difference in thermal expansion coefficient can degrade the flatness of the structure, which is detrimental to the implementation of the subsequent manufacturing steps of the electronic device, and reduce the mechanical strength of the bonding.
• the difference in crystalline quality which does not allow an alignment of the crystalline grains on either side of the bonding interface, can cause a loss of electrical conductivity at the interface.
• An object of the invention is to design a method for manufacturing a semiconductor structure comprising an active layer of monocrystalline SiC on a support substrate of polycrystalline SiC, which makes it possible to minimize the disadvantages linked to the difference in crystalline quality and polytype at the interface between the active layer and the supporting substrate.
• the invention proposes a method for manufacturing a semiconductor structure comprising a support substrate of polycrystalline silicon carbide (SiC) and an active layer of monocrystalline silicon carbide, comprising: - the formation of a support substrate comprising a stack of a first layer of polycrystalline SiC mainly of the 3C polytype and a second layer of polycrystalline SiC mainly of the 4H and/or 6H polytype,
• the interface between the layers of different crystalline qualities has been separated (which remains at the bonding interface between the active layer and the support substrate), and the interface between the layers of different polytypes (which is buried in the support substrate, at a distance from the bonding interface).
• the term "mainly of the 3C polytype” means that the volume proportion of grains of 3C structure in the first layer is greater than or equal to 60%, preferably greater than or equal to 70%, or even greater than or equal to 80 %.
• the expression “mainly of the 4H and/or 6H polytype” means that the volume proportion of grains of 4H and/or 6H structure in the second layer is greater than or equal to 60%, preferably greater than or equal to 70% , and even more preferably greater than or equal to 80%.
• first and second designate the two layers of polycrystalline SiC of different polytypes of the support substrate, without inducing a particular order of formation of said layers.
• the first layer is grown on a seed substrate then the second layer is grown on the first layer, so that the support substrate directly presents a free surface mainly of the 4H and/or 6H polytype for bonding the donor substrate.
• the second layer is grown on a seed substrate, then the first layer is grown on the second layer.
• the seed substrate is removed in order to free the face of the second layer situated on the side of the seed substrate.
• the formation of the support substrate comprises the growth of the first layer on a seed substrate then the growth of the second layer on the first layer;
• the formation of the support substrate successively comprises the growth of the second layer on a seed substrate, the growth of the first layer on the second layer, and the removal of the seed substrate to expose one face of the second layer for the bonding of the donor substrate ;
• the seed substrate is a monocrystalline or polycrystalline SIC substrate mainly of the 4H and/or 6H polytype;
• the first layer is grown to a thickness of between 1 and 20 ⁇ m
• the second layer is grown to a thickness of between 80 and 350 ⁇ m
• the first layer is grown to a thickness of between 80 and 200 ⁇ m
• the second layer is grown to a thickness of between 150 and 270 ⁇ m
• CVD chemical vapor deposition
• the growth of the first layer is carried out at a temperature between 1100 and 1500° C., preferably between 1200 and 1400° C.;
• the growth of the second layer is carried out at a temperature comprised between 1500 and 2600°C, preferably comprised between 1700 and 1900°C or between 1800 and 2400°C, or even comprised between 2000 and 2250°C;
• the method further comprises the introduction of dopants during the growth of the first and of the second layer;
• the donor substrate is bonded directly to the face of the 4H and/or 6H polytype of the support substrate;
• the donor substrate is bonded to the face of the 4H and/or 6H polytype of the support substrate via a bonding layer;
• the bonding layer comprises silicon or tungsten
• the method comprises, before bonding, a step of implanting atomic species in the donor substrate to form a zone of weakness delimiting the active layer and, after bonding, a step of detaching the donor substrate along the zone embrittlement to transfer the active layer onto the support substrate;
• the first layer is grown to a thickness of between 1 and 20 ⁇ m, after the transfer of the active layer to the support substrate, the first layer is removed.
• Another object of the invention relates to a semiconductor structure comprising successively, from its rear face to its front face:
• the term “successively” specifies a spatial order of the layers but does not necessarily induce a direct contact between said layers.
• the first layer has a thickness between 80 and 350 ⁇ m and the second layer has a thickness between 1 and 20 ⁇ m. In other embodiments, the first layer has a thickness between 80 and 200 ⁇ m and the second layer has a thickness between 150 and 270 ⁇ m.
• Another object of the invention relates to an electronic device, in particular for power applications or radio frequency applications, comprising a structure as described above and at least one electronic component, such as a transistor, a diode, an electronic component power, and / or a radio frequency electronic component, arranged in or on the active layer.
• an electronic component such as a transistor, a diode, an electronic component power, and / or a radio frequency electronic component, arranged in or on the active layer.
• FIG. 1 shows a sectional view of a semiconductor structure according to a first embodiment
• FIG. 2 shows a sectional view of a structure according to a second embodiment
• Figures 3A to 3D schematically represent steps of a method of manufacturing the semiconductor structure of Figure 1;
• FIG. 4A to 4D schematically represent steps of a method of manufacturing the semiconductor structure of Figure 2;
• FIG. 5A to 5D schematically represent steps of a variant of the processes of Figures 3A-3D and 4A-4D.
• the present description relates to a semiconductor structure comprising a support substrate of polycrystalline SiC and an active layer of monocrystalline SiC extending over the support substrate.
• the support substrate comprises two layers of polycrystalline SiC of different polytypes: a first layer mainly of the 3C polytype and a second layer mainly of the 4H and/or 6H polytype.
• the first and the second layer of polycrystalline SiC can have different configurations in the structure, which will be described below.
• the active layer is made of monocrystalline SiC to present optimal electrical properties.
• the active layer has a hexagonal structure, mainly of the 4H or 6H polytype.
• the active layer is attached by bonding to the support substrate, on one face of the 4H and/or 6H polytype. This bonding can be direct or indirect, by means of a bonding layer.
• the active layer is bonded to a layer of polycrystalline SiC of a polytype which is also hexagonal.
• the materials present at the bonding interface have band structures that are closer than in the case of bonding between a material with a hexagonal structure and a material with a cubic structure, which can be favorable to better electrical conductivity at the interface level.
• this similarity between the hexagonal structures present at the interface makes it possible to reduce the difference in thermal expansion coefficient on either side of the interface. As a result, it is possible to avoid the risks of plastic deformation during the high-temperature manufacturing steps, as well as focusing defects due to curvatures of the structure during the lithography steps implemented subsequently for the manufacture of electronic devices.
• a first interface is the interface between the monocrystalline active layer and the polycrystalline support substrate, which is an interface between layers of different crystalline qualities but of similar polytypes.
• a second interface is the interface between the first and the second polycrystalline SiC layer of the support substrate, which is an interface between layers of different polytypes but of similar crystalline qualities. This second interface is located in the thickness of the support substrate and is therefore distant from the first interface.
• the second interface does not necessarily mark an abrupt passage from the cubic polytype to the hexagonal polytype, but may comprise a transition zone presenting a certain thickness, which can typically go up to 20 ⁇ m. However, considering the thickness of the second layer, even with such a transition zone, the first interface is far enough from the second interface.
• the structure comprises successively, from its rear face towards its front face, a seed substrate 10, the first layer 11 of polycrystalline SiC mainly of the polytype 3C, the second layer 12 of SiC polycrystalline mainly of the 4H and/or 6H polytype (the seed substrate and the layers 11 and 12 together forming the support substrate 1) and the active layer 2 of monocrystalline SiC of the 4H or 6H polytype.
• the seed substrate 10 is used for the growth of the first layer 11. It can therefore be removed from the structure when its presence is no longer necessary.
• the first layer 11 is substantially thicker than the second layer 12.
• the first layer 11 has a thickness of between 80 and 350 ⁇ m while the second layer 12 has a thickness of between between 1 and 20 pm.
• the 3C polytype being likely to be obtained at a lower temperature than the 4H or 6H polytypes, the manufacture of this first embodiment of the structure is more energy efficient.
• a rear part of the first layer 11 can optionally be removed.
• Said structure has a first interface 11 between the active layer 2 which is monocrystalline and the support substrate 1 which is polycrystalline.
• the active layer 2 is represented in direct contact with the second layer of polycrystalline SiC 12, but it would also be possible to have a bonding layer (of the type of the layer referenced 3 in FIG. 2) at the interface between these two layers.
• a bonding layer can typically be made of silicon or tungsten, so as to promote the mechanical strength of the bonding while ensuring electrical conduction between the active layer 2 and the support substrate 1 .
• the structure has a second interface I2 between the first layer 11 which is mainly of the 3C polytype and the second layer 12 which is mainly of the 4H and/or 6H polytype.
• the interfaces 11 and I2 are therefore separated by the thickness of the second layer 12.
• the structure successively comprises, from its rear face to its front face, a seed substrate 10, the first layer 11 of polycrystalline SiC mainly of the 3C polytype, the second layer 12 of SiC polycrystalline mainly of the 4H and/or 6H polytype (the seed substrate and the layers 11 and 12 together forming the support substrate 1), a bonding layer 3 and the active layer 2 of monocrystalline SiC of the 4H or 6H polytype.
• the seed substrate 10 is used for the growth of the first layer 11. It can therefore be removed from the structure when its presence is no longer necessary.
• the first layer 11 is substantially thinner than the second layer 12.
• the first layer 11 has a thickness of between 80 and 200 ⁇ m while the second layer 12 has a thickness of between between 150 and 270 pm.
• the fact that the structure layer cubic is thinner makes it possible to limit the deformations due to the difference in coefficient of thermal expansion between the 3C and 4H/6H structures.
• Said structure has a first interface 11 between the active layer 2 which is monocrystalline and the support substrate 1 which is polycrystalline.
• a bonding layer 3 is shown between the active layer 2 and the second layer of polycrystalline SiC 12, but this bonding layer is optional and it would also be possible to achieve direct bonding between layers 2 and 12.
• the bonding layer 3 can typically be made of silicon or tungsten, so as to promote the mechanical strength of the bonding while ensuring electrical conduction between the active layer 2 and the support substrate 1.
• the structure has a second interface I2 between the first layer 11 which is mainly of the 3C polytype and the second layer 12 which is mainly of the 4H and/or 6H polytype.
• the interfaces 11 and I2 are therefore separated by the thickness of the second layer 12.
• the first layer 11 can be removed, in which case the second interface is no longer present in the final structure.
• the structure still benefits from the first interface 11 between two layers of hexagonal structure, which, as explained above, is favorable both due to a reduced difference in coefficients of thermal expansion and a greater proximity of the band structures.
• Figures 3A to 3D schematically illustrate the steps of a method of manufacturing the structure of Figure 1.
• the first layer 11 of polycrystalline SiC is formed on the seed substrate 10.
• the seed substrate 10 is typically a graphite substrate, but any other material whose coefficient of thermal expansion is close to that of polycrystalline SiC and which preferably has a low cost and/or is reusable can be used.
• Alternative materials to graphite are thus sintered polycrystalline SiC and monocrystalline SiC (non-exhaustive list).
• the first layer 11 can be formed by chemical vapor deposition (CVD, acronym of the Anglo-Saxon term “Chemical Vapor Deposition”). This deposition may involve the following precursors (non-limiting examples):
• silane silane, tetrachlorosilane, trichlorosilane, or dichlorosilane
• a carrier gas which may be chosen from nitrogen, argon, helium and dihydrogen.
• a person skilled in the art is able to define the deposition parameters, in particular the temperature, according to the precursors used and the installation used to carry out the deposition.
• a relatively low deposition temperature is used, typically between 1100 and 1500°C, preferably between 1200 and 1400°C.
• Said first layer 11 is grown to a thickness of between 80 and 350 ⁇ m. The growth usually takes place on both sides of the seed substrate, so that a layer of polycrystalline SiC mainly of the 3C polytype also forms on the back side of the seed substrate. As this layer is not intended to be kept in the structure, it has not been shown for the sake of simplifying the drawings.
• the second layer 12 of polycrystalline SiC is formed on the first layer 11, to obtain the support substrate 1.
• the second layer 12 can also be formed by chemical deposition in the vapor phase but, to obtain a hexagonal structure, a relatively high deposition temperature is used, typically between 1500 and 2600°C, preferably between 1700 and 1900°C or between 1800 and 2400°C, or even between 2000 and 2250°C.
• the growth temperature depends in particular on the deposition technique, the precursors used and the other operating conditions and is therefore given only as an indication, the person skilled in the art being able to define a growth process adapted to the desired polytype.
• the precursors can be chosen from the same list as that presented above for the deposition of the first layer.
• the second layer can be formed by high temperature chemical vapor deposition (HTCVD, acronym for the English term “High Temperature Chemical Vapor Deposition), by liquid phase growth (known technique under the acronym TSSG of the Anglo-Saxon term “Top Seeded Solution Growth”, or else by physical vapor deposition (PVD or PVT).
• HTCVD high temperature chemical vapor deposition
• TSSG liquid phase growth
• PVD physical vapor deposition
• the deposition at such a temperature requires very high energy, the fact that the second layer is formed over a small thickness (between 1 ⁇ m and 20 ⁇ m) makes it possible to limit the overall energy consumption and the cost of the process.
• the deposition of the second layer is advantageously carried out in the same frame as the first layer, in which the deposition temperature is increased to modify the polytype of the SiC deposited.
• the first layer 11 is formed by a sintering process before being transferred to a deposition chamber in which the second layer 12 is then deposited on the first layer 11 by one of the techniques of deposition or growth mentioned previously.
• the transition between the cubic structure of the first layer and the hexagonal structure of the second layer of polycrystalline SiC may not be straightforward but may present a transition zone comprising a mixture of type 3C grains and type 4H and/or 6H grains. , over a thickness of up to 20 ⁇ m. However, insofar as this transition zone is distant from the bonding interface between the active layer and the support substrate, it is not detrimental to the performance of the structure.
• the first and the second layer are doped by introducing dopants during their growth, according to a known technique.
• the dopants can typically be nitrogen, boron, phosphorus or aluminum, depending on the type of doping desired.
• the dopant content is generally between 10 18 and 10 21 at/cm 3 .
• a donor substrate 20 is provided in which, by implantation of atomic species (typically hydrogen and/or helium), a zone of weakness 21 delimiting the active layer 2 to be transferred is formed.
• the donor substrate 20 is a 4H or 6H polytype monocrystalline SiC substrate, commercially available in a suitable size, typically of the order of 150 to 200 mm in diameter.
• the donor substrate 20 is glued to the support substrate 1 .
• any suitable surface treatment is applied to ensure that the surfaces in contact are as little rough as possible, that is to say in particular have a roughness less than 1 nm RMS, preferably less than 0.5 nm RMS, and more preferably less than 0.2 nm RMS.
• the surfaces are advantageously rendered hydrophobic.
• the donor substrate is detached along the embrittlement zone 21 so as to transfer the active layer 2 onto the support substrate 1 and obtain the structure of FIG.
• Figures 4A to 4D schematically illustrate the steps of a method of manufacturing the structure of Figure 2.
• the first layer 11 of polycrystalline SiC is formed on the seed substrate 10.
• Seed substrate 10 is typically a graphite substrate.
• the first layer 11 is formed by chemical vapor deposition (CVD, acronym of the Anglo-Saxon term “Chemical Vapor Deposition”). To obtain a cubic structure, a relatively low deposition temperature is used, typically between 1100 and 1500°C, preferably between 1200 and 1400°C. Said first layer 11 is grown to a thickness of between 1 and 20 ⁇ m.
• the second layer 12 of polycrystalline SiC is formed on the first layer 11 , to obtain the support substrate 1 .
• the second layer 12 is also formed by chemical vapor deposition but, to obtain a hexagonal structure, a relatively high deposition temperature is used, typically between 1500 and 2600° C., preferably between 1700 and 1900°C or between 1800 and 2400°C, or even between 2000 and 2250°C. As indicated above, those skilled in the art are able to determine the growth conditions for the desired polytype depending on the technique employed and the precursors used.
• the second layer is formed to a thickness of between 80 and 350 ⁇ m.
• the deposition of the second layer is advantageously carried out in the same frame as the first layer, in which the deposition temperature is increased to modify the polytype of the SiC deposited.
• the transition between the cubic structure of the first layer and the hexagonal structure of the second layer of polycrystalline SiC may not be straight but present a transition zone comprising a mixture of type 3C grains and type grains 4H and/or 6H.
• the first and the second layer are doped by introducing dopants during their growth, according to a known technique.
• the dopants can typically be nitrogen, boron, phosphorus or aluminum, depending on the type of doping desired.
• the dopant content is generally between 10 18 and 10 21 at/cm 3 .
• a donor substrate 20 is provided in which, by implantation of atomic species (typically hydrogen and/or helium), a zone of weakness 21 delimiting the active layer 2 to be transferred is formed.
• the donor substrate 20 is a 4H or 6H polytype monocrystalline SiC substrate, commercially available in a suitable size, typically of the order of 150 to 200 mm in diameter.
• the donor substrate 20 is bonded to the support substrate 1 via the bonding layer 3.
• the bonding layer 3 can be deposited beforehand either on the donor substrate 20, or on the second layer 12 of the support substrate 1.
• a prior treatment of the surfaces to be bonded can be implemented so as to obtain a very low roughness, typically less than 1 nm RMS, preferably less than 0.5 nmRMS.
• the donor substrate is detached along the weakened zone 21 so as to transfer the active layer 2 onto the support substrate 1 and obtain the structure of FIG. 2.
• the second layer (4H and/or 6H polytype) is sufficiently thick, i.e. it has a thickness greater than or equal to 100 ⁇ m, it is possible to remove the first layer (3C polytype ), in particular after the formation of an electronic component in the active layer.
• This removal of the first layer can be carried out by grinding or any other means. It makes it possible to expose, on the rear face of the structure, a surface of the 4H and/or 6H polytype, on which an electrical contact can then be deposited in cases where the geometry of the component requires a contact on the rear face.
• the methods described above are based on the successive growth, on a seed substrate, of the first layer of polycrystalline SiC, mainly of the 3C polytype, then of the second layer of polycrystalline SiC, mainly of the 4H and/or 6H polytype.
• To transfer the monocrystalline active layer of type 4H or 6H onto a surface of the polytype 4H and/or 6H (which, as indicated above, is more favorable due to the proximity of the coefficients of thermal expansion and of the band structures), it is It is then necessary to remove the seed substrate to expose the face of the second layer of polycrystalline SiC, and to invert the support substrate to bond the donor substrate to said second layer.
• FIGS. 5A to 5D This variant is illustrated in FIGS. 5A to 5D. This process can be used to form the semiconductor structure of Figure 1 or the semiconductor structure of Figure 2.
• the second layer 12 of polycrystalline SiC is formed on the seed substrate 10.
• seed substrate 10 is preferably a monocrystalline or polycrystalline SiC substrate mainly of the 4H and/or 6H polytype.
• the second layer 12 is formed by chemical vapor deposition with a relatively high deposition temperature is used, typically between 1500 and 2600°C, preferably between 1700 and 1900°C or between 1800 and 2400°C, or even between 2000 and 2250°C. As indicated above, those skilled in the art are able to determine the growth conditions for the desired polytype depending on the technique employed and the precursors used.
• the first layer 11 is formed by chemical vapor deposition at a relatively low deposition temperature, typically between 1100 and 1500°C, preferably between 1200 and 1400°C.
• the filing of the first layer is advantageously made in the same frame as that of the second layer, by lowering the deposition temperature to promote a change of polytype of the deposited SiC.
• the first and the second layer are doped by introducing dopants during their growth, according to a known technique.
• the dopants can typically be nitrogen, boron, phosphorus or aluminum, depending on the type of doping desired.
• the dopant content is generally between 10 18 and 10 21 at/cm 3 .
• the seed substrate 10 is removed so as to expose the rear face of the second layer 12, which is mainly of the 4H and/or 6H polytype.
• the support substrate 1 therefore only consists of layers 11 and 12.
• a donor substrate 20 is also provided in which atomic species (typically hydrogen and/or helium ) a zone of weakness 21 delimiting the active layer 2 to be transferred.
• the donor substrate 20 is a 4H or 6H polytype monocrystalline SiC substrate, commercially available in a suitable size, typically of the order of 150 to 200 mm in diameter.
• the donor substrate 20 is bonded to the support substrate 1 either directly or via the bonding layer described above.
• the support substrate is reversed so that the second layer 12, which was on the rear side during the manufacture of the support substrate, is oriented towards the front to receive the donor substrate 20.
• the donor substrate is detached along the zone of weakness 21 so as to transfer the active layer 2 onto the support substrate 1 and obtain a semiconductor structure similar to that of FIGS. 1 and 2, in which the support substrate 1 lacks the seed substrate 10.
• the semiconductor structure obtained can advantageously be used for the manufacture of electronic devices for power applications and/or radio frequency applications.
• one or more additional semi-conducting layers can be formed by epitaxial recovery on the active layer, intended for the formation of electronic components.
• the electronic components formed in or on the active layer can comprise: one or more transistors, one or more diodes, one or more power components, one or more radio frequency components (non-limiting list).
• a radiofrequency component typically comprises a line for transmitting a radiofrequency electrical signal and optionally one or more transistors.
• a power component is defined as being a component adapted to carry an electric current having a power of 50 W or more.

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• 2021
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