WO2022158085A1 - 半導体基板及びその製造方法、及び半導体装置 - Google Patents
半導体基板及びその製造方法、及び半導体装置 Download PDFInfo
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Definitions
- the present embodiment relates to a semiconductor substrate, its manufacturing method, and a semiconductor device.
- SiC silicon carbide
- a method of forming a SiC wafer for example, a method of forming a SiC epitaxial growth layer by a chemical vapor deposition (CVD) method on a SiC single crystal substrate by a sublimation method, or a method of forming a SiC epitaxial growth layer on a SiC CVD polycrystalline substrate
- CVD chemical vapor deposition
- SiC devices such as Schottky Barrier Diodes (SBDs), MOSFETs (Metal Oxide Semiconductor Field Effect Transistors), and IGBTs (Insulated Gate Bipolar Transistors) have been provided for power control applications.
- SBDs Schottky Barrier Diodes
- MOSFETs Metal Oxide Semiconductor Field Effect Transistors
- IGBTs Insulated Gate Bipolar Transistors
- SiC semiconductor substrates on which such SiC-based devices are formed are produced by bonding a single-crystal SiC semiconductor substrate to a polycrystalline SiC semiconductor substrate in order to reduce manufacturing costs and provide desired physical properties. It was made.
- the high-quality single-crystal SiC semiconductor substrate is bonded to the polycrystalline SiC semiconductor substrate without defects. I needed it.
- polishing to ensure the surface roughness necessary for bonding a single-crystal SiC semiconductor substrate to a polycrystalline SiC semiconductor substrate by room temperature bonding or diffusion bonding is costly, and defects occurring at the bonding interface reduce yield. sometimes decreased.
- the present embodiment provides a low-cost, high-quality semiconductor substrate, its manufacturing method, and a semiconductor device.
- a SiC single crystal layer comprising a SiC polycrystalline growth layer.
- a semiconductor device including the above semiconductor substrate is provided.
- forming a hydrogen ion implanted layer on the C-plane of a SiC single crystal substrate forming a SiC polycrystalline growth layer on the C-plane of the SiC single crystal substrate; Along with the step of forming the SiC polycrystalline growth layer, the step of embrittlement of the hydrogen ion-implanted layer to form a single-crystal SiC thinned layer; removing a first laminate of SiC polycrystalline growth layers; smoothing the surface of the separated single-crystal SiC thinned layer; and growing SiC epitaxially on the smoothed surface of the single-crystal SiC thinned layer. and forming a layer.
- forming a hydrogen ion implanted layer on a Si surface of a SiC single crystal substrate forming a SiC epitaxially grown layer on the Si surface of the SiC single crystal substrate;
- the step of embrittlement of the hydrogen ion implanted layer to form a single crystal SiC thinned layer the step of attaching a temporary substrate to the Si surface of the SiC epitaxial growth layer, the SiC single layer a step of peeling off the single-crystal SiC thinned layer, the SiC epitaxially grown layer, and the second laminate of the temporary substrate from the crystal substrate; and a step of smoothing the surface of the peeled single-crystal SiC thinned layer; and forming a SiC polycrystalline growth layer on the smoothed surface of the single-crystal SiC thinned layer.
- the present embodiment it is possible to provide a low-cost, high-quality semiconductor substrate, its manufacturing method, and a semiconductor device.
- FIG. 1 is a method of manufacturing a semiconductor substrate according to the first embodiment, and shows a cross-sectional view of a structure in which a hydrogen ion-implanted layer and a phosphorus ion-implanted layer are formed on the C-plane of a SiC single crystal substrate.
- FIG. 2 is a method of manufacturing a semiconductor substrate according to the first embodiment, and shows a cross-sectional view of a structure in which a SiC polycrystalline growth layer is formed on the C-plane of the phosphorus ion-implanted layer by CVD.
- FIG. 1 is a method of manufacturing a semiconductor substrate according to the first embodiment, and shows a cross-sectional view of a structure in which a hydrogen ion-implanted layer and a phosphorus ion-implanted layer are formed on the C-plane of a SiC single crystal substrate.
- FIG. 2 is a method of manufacturing a semiconductor substrate according to the first embodiment, and shows a cross-sectional view of
- FIG. 3A shows a method of manufacturing a semiconductor substrate according to the first embodiment, in which the single-crystal SiC thinned layer is separated from the SiC single-crystal substrate via the peeling surface, and the SiC polycrystalline growth layer and the SiC multi-layer are separated from the SiC single-crystal substrate.
- FIG. 4 shows a cross-sectional view of a structure in which a SiC single crystal layer is formed on a crystal growth layer;
- FIG. 3B shows a cross-sectional view of the structure of the SiC single crystal substrate that has been peeled and separated.
- FIG. 4 is a method of manufacturing a semiconductor substrate according to the first embodiment, and shows a cross-sectional view of a structure in which the Si surface of the SiC single crystal layer is polished.
- FIG. 5 is a method of manufacturing a semiconductor substrate according to the first embodiment, showing a cross-sectional view of a structure in which a SiC epitaxial growth layer is formed on a SiC thinned layer.
- FIG. 6 is a method of manufacturing a semiconductor substrate according to the second embodiment, and shows a cross-sectional view of a structure in which a hydrogen ion-implanted layer is formed on the Si surface of a SiC single crystal substrate.
- FIG. 7 shows a method of manufacturing a semiconductor substrate according to the second embodiment.
- FIG. 4 shows a cross-sectional view of a structure in which a SiC epitaxial growth layer is formed on the Si surface of the thinned layer.
- FIG. 8 shows a method of manufacturing a semiconductor substrate according to the second embodiment, in which an adhesive layer is applied to the Si surface of the SiC epitaxial growth layer, a graphite substrate is attached, and then weakening annealing is performed to form a single unit.
- FIG. 9 shows a method of manufacturing a semiconductor substrate according to the second embodiment. After smoothing the peeled surface of the single-crystal SiC thin layer, P ions are implanted onto the C-plane of the single-crystal SiC thin layer.
- 1 shows a cross-sectional view of a structure in which a phosphorus ion-implanted layer is formed.
- FIG. 10 shows a cross-sectional view of a structure in which a C-plane is exposed facing upward and a SiC polycrystalline growth layer is formed on the same surface by a CVD method.
- FIG. 11 shows a cross-sectional view of the structure from which the carbon tray is removed in the method of manufacturing a semiconductor substrate according to the second embodiment.
- FIG. 12 shows a cross-sectional view of a Schottky barrier diode manufactured using the semiconductor substrate according to the embodiment.
- FIG. 13 shows a cross-sectional view of a trench gate type MOSFET manufactured using the semiconductor substrate according to the embodiment.
- FIG. 14 shows a cross-sectional view of a planar gate type MOSFET manufactured using the semiconductor substrate according to the embodiment.
- FIG. 15A shows a plan view for explaining crystal planes of SiC.
- FIG. 15B shows a side view illustrating crystal planes of SiC.
- FIG. 16 shows a bird's-eye view of a semiconductor substrate (wafer) according to the embodiment.
- FIG. 17A shows a bird's-eye view of a 4H—SiC crystal unit cell applicable to the SiC epitaxial substrate of the semiconductor substrate according to the embodiment.
- FIG. 17B shows a configuration diagram of the two-layer portion of the 4H—SiC crystal.
- FIG. 17C shows a configuration diagram of a four-layer portion of 4H—SiC crystal.
- FIG. 18 shows a configuration diagram of the unit cell of the 4H—SiC crystal
- [C] indicates the C face of SiC
- [S] indicates the Si face of SiC
- the semiconductor substrate 1 includes a hexagonal SiC single crystal layer 13I and a SiC epitaxial growth layer (SiC- epi) 12E, and a SiC polycrystalline growth layer (SiC-poly CVD) 18PC arranged on the C plane facing the Si plane of the SiC single crystal layer 13I.
- SiC- epi SiC epitaxial growth layer
- SiC-poly CVD SiC polycrystalline growth layer
- the SiC single crystal layer 13I includes a thin single crystal SiC layer 10HE, as shown in FIG.
- the monocrystalline SiC thinned layer 10HE comprises a first ion-implanted layer.
- the first ion-implanted layer comprises a hydrogen ion-implanted layer 10HI, as shown in FIG.
- the monocrystalline SiC thinned layer 10HE comprises an embrittlement layer of the hydrogen ion implanted layer 10HI.
- the SiC single crystal layer 13I may include a second ion-implanted layer.
- the second ion-implanted layer is arranged between the single-crystal SiC thin layer 10HE and the SiC polycrystalline growth layer 18PC, as shown in FIG.
- the second ion-implanted layer may comprise a phosphorus ion-implanted layer 10PI, as shown in FIG.
- the Si plane of the SiC single crystal layer 13I is, for example, the [0001] oriented plane of 4H-SiC
- the C plane of the SiC single crystal layer 13I is the [000-1] oriented plane of 4H-SiC. is.
- the SiC single crystal substrate 10SB can be reused by being separated from the SiC epitaxial growth layer 12E.
- FIG. 1 A cross-sectional view of a structure in which a hydrogen ion-implanted layer 10HI and a phosphorus ion-implanted layer 10PI are sequentially formed on the C-plane of a SiC single crystal substrate (SiCSB) 10SB in the semiconductor substrate manufacturing method according to the first embodiment is shown in FIG. 1 is represented.
- SiCSB SiC single crystal substrate
- the single crystal SiC thinned layer 10HE is separated from the SiC single crystal substrate 10SB via the separation plane BP, and the SiC polycrystalline growth layer 18PC and the SiC thinned layer 10HE are separated from the SiC single crystal substrate 10SB.
- a cross-sectional view of the structure in which the SiC single crystal layer 13I is formed on the polycrystalline growth layer 18PC is represented as shown in FIG. 3A.
- FIG. 3B a cross-sectional view of the structure of the peeled/separated SiC single crystal substrate 10SB is shown in FIG. 3B.
- FIG. 4 shows a cross-sectional view of a structure obtained by polishing the Si surface of the SiC single crystal layer 13I in the semiconductor substrate manufacturing method according to the first embodiment.
- FIG. 1 A cross-sectional view of a structure in which a SiC epitaxial growth layer 12E is formed on the Si surface of the SiC single crystal layer 13I in the semiconductor substrate manufacturing method according to the first embodiment is shown in FIG. .
- an ion implantation delamination method is applied.
- a single-crystal SiC thinned layer 10HE can be formed on the surface of the SiC single-crystal substrate 10SB by ion implantation delamination.
- the ion implantation delamination method has the following steps.
- an annealing process is performed to weaken the hydrogen ion-implanted layer 10HI to form a thin single-crystal SiC layer 10HE.
- the embrittled hydrogen ion-implanted layer 10HI becomes the single-crystal SiC thinned layer 10HE.
- the annealing treatment is embrittlement thermal annealing treatment. This is a process for generating hydrogen microbubbles after hydrogen ion implantation to facilitate breaking of the single-crystal SiC thin layer 10HE.
- a delamination surface BP is formed in the single crystal SiC thinned layer 10HE when a stress such as a shear stress is applied.
- the method of manufacturing a semiconductor substrate according to the first embodiment is a method of manufacturing a semiconductor substrate 1 having a single crystal SiC thin layer 10HE and a SiC epitaxial growth layer 12E on a SiC polycrystalline growth layer 18PC.
- the substrate bonding method is not used for the interface bonding of the first surface and the second surface.
- the method for manufacturing a semiconductor substrate according to the first embodiment includes a step of thinning the (000-1)C plane of the hexagonal SiC single crystal substrate 10SB by an ion implantation delamination method.
- the manufacturing method of the semiconductor substrate according to the first embodiment has the following steps. That is, a step of forming the hydrogen ion implanted layer 10HI on the C-plane of the SiC single-crystal substrate 10SB, a step of forming the SiC polycrystalline growth layer 18PC on the C-plane of the SiC single-crystal substrate 10SB, and a step of forming the SiC polycrystalline growth layer Along with the step of forming 18PC, the step of embrittlement of the hydrogen ion-implanted layer 10HI to form a thin single-crystal SiC layer 10HE, and the thin single-crystal SiC layer 10HE and the SiC polycrystalline growth layer from the SiC single-crystal substrate 10SB.
- a hydrogen ion-implanted layer 10HI having a prescribed depth is formed by implanting hydrogen ions by an ion implantation delamination method.
- the acceleration energy is, for example, about 100 keV
- the dose amount is, for example, about 2.0 ⁇ 10 17 /cm 2 .
- the depth of the phosphorus ion-implanted layer 10PI is, for example, about 0.01 ⁇ m to 0.5 ⁇ m.
- the acceleration energy is, for example, approximately 10 keV to 180 keV
- the dose amount is, for example, approximately 4.times.10.sup.15/ cm.sup.2 to 6.times.10.sup.16 / cm.sup.2 .
- a SiC polycrystalline growth layer 18PC is formed on the C plane of the SiC single crystal substrate 10SB.
- the SiC polycrystalline growth layer 18PC can be deposited on the C-plane of the SiC single crystal substrate 10SB by, for example, the CVD method.
- the thickness of the SiC polycrystalline growth layer 18PC is desirably about 150 ⁇ m to 500 ⁇ m, for example.
- the thickness of the semiconductor substrate 1 (see FIG. 5) is adjusted to about 150 ⁇ m to 500 ⁇ m as required.
- the thickness of the semiconductor substrate 1 is the sum of the layers of the SiC polycrystalline growth layer 18PC, the SiC single crystal layer 13I, and the SiC epitaxial growth layer 12E.
- the hydrogen ion-implanted layer 10HI can be embrittled at the same time as the high-temperature treatment during deposition of the SiC polycrystalline growth layer 18PC. At the same time, activation annealing for hydrogen ions, P ions, etc. is performed. The hydrogen ion-implanted layer 10HI is weakened at the same time as the heat treatment during the formation of the SiC polycrystalline growth layer 18PC, thereby forming the single crystal SiC thinned layer 10HE.
- the first is hydrogen ion implantation for the ion implantation separation method.
- hydrogen ions protons
- hydrogen microbubbles are generated to embrittle the hydrogen ion implanted layer 10HI.
- the hydrogen ions accumulate at a depth of about 1 ⁇ m.
- thermal annealing is performed, hydrogen ions are gasified to form a porous layer inside the SiC single crystal substrate 10SB. This porous layer embrittles the SiC single-crystal substrate 10SB to form a fragile layer of the hydrogen ion-implanted layer 10HI, that is, a thin single-crystal SiC layer 10HE.
- the thin single-crystal SiC layer 10HE is made easier to break at the broken surface BP. Due to the weakening of the hydrogen ion-implanted layer 10HI, it is possible to avoid the occurrence of crystal defects and warpage due to the difference in coefficient of thermal expansion (CTE) between the SiC single crystal substrate 10SB and the SiC polycrystalline growth layer 18PC. can.
- CTE coefficient of thermal expansion
- the second ion implantation is P ion implantation for reducing the ohmic contact resistance at the contact interface between the SiC single crystal substrate 10SB and the SiC polycrystalline growth layer 18PC, and the donor density near the implantation surface is about 1 ⁇ 10 18 /.
- Multistage P ion implantation is performed so that the concentration is cm 3 to 1 ⁇ 10 20 /cm 3 .
- an activation thermal anneal is required to activate the P ions and improve the donor density.
- Both of these annealings are simultaneously achieved by heating the substrate during the deposition of the SiC polycrystalline growth layer 18PC by the CVD method.
- a laminate (18PC, 10PI, 10HE) of a single-crystal SiC thin layer 10HE, a phosphorus ion-implanted layer 10HP, and a SiC polycrystalline growth layer 18PC is formed from the SiC single-crystal substrate 10SB. exfoliate.
- the peeling step is performed on the peeled surface BP of the single-crystal SiC thinned layer 10HE subjected to the embrittlement treatment.
- the uneven structure of the single-crystal SiC thinned layer 10HE is exposed on the C-plane of the separated SiC single-crystal substrate 10SB.
- the uneven structure of the thin single-crystal SiC layer 10HE is subjected to a mechanical polishing method and a mechanical-chemical polishing method in order to smooth the Si surface of the SiC single-crystal substrate 10SB.
- the C plane of the SiC single crystal substrate 10SB has an average surface roughness Ra of, for example, about 1 nm or less due to the above process. As a result, the SiC single crystal substrate 10SB can be reused.
- the SiC single crystal substrate 10SB becomes reusable.
- the surface of the separated single-crystal SiC thin layer 10HE is smoothed by sequentially using a mechanical polishing method and a mechanical-chemical polishing method.
- the Si surface of the thin single-crystal SiC layer 10HE has an average surface roughness Ra of, for example, about 1 nm or less due to the above process.
- a SiC epitaxial growth layer 12E having good crystallinity is formed on the smoothed surface by homoepitaxial growth by CVD.
- the CVD apparatus for forming the SiC epitaxial growth layer 12E by homoepitaxial growth may be the same CVD apparatus as the CVD apparatus for forming the SiC polycrystalline growth layer 18PC on the C-plane of the SiC single crystal substrate 10SB. They may be configured as separate dedicated devices.
- the semiconductor substrate according to the first embodiment can be formed.
- a single-crystal SiC thinned layer is formed by ion implantation delamination to the C-plane of a hexagonal SiC single-crystal substrate, and furthermore, the C-plane of the single-crystal SiC thinned layer is By combining the direct growth of the SiC polycrystalline layer, it is possible to provide a semiconductor substrate and its manufacturing method that do not use a substrate bonding method for the SiC epitaxially grown layer and the SiC polycrystalline layer.
- a single-crystal SiC thin layer is formed on the C surface of a SiC single-crystal substrate by an ion implantation delamination method, and the single-crystal SiC thin layer is subjected to a CVD method to form a polycrystalline SiC layer.
- a laminate of SiC epitaxial growth layers and SiC polycrystalline growth layers is produced by combining the ion implantation delamination method and the CVD direct deposition technology without bonding the substrates. of semiconductor substrates can be produced.
- a hexagonal SiC single crystal substrate is thinned and an epitaxial growth layer is formed on the single crystal SiC thinned layer by homoepitaxial growth.
- the Si face of the SiC epitaxially grown layer of the crystal system is obtained.
- a SiC single crystal substrate which is more expensive than a Si substrate, is used as a seed substrate, the seed substrate can be reused several tens of times or more. not much change.
- the thin single crystal SiC layer is basically formed by the ion implantation delamination method, but it is not necessary to remove the holding substrate by polishing or etching. Since a hexagonal SiC epitaxial growth layer can be obtained, it can be used as a semiconductor substrate for a SiC-based power device.
- the first embodiment is a method for manufacturing a semiconductor substrate having a SiC epitaxial growth layer on a SiC polycrystalline substrate, wherein the (000-1) C plane of a hexagonal single crystal SiC substrate is subjected to an ion implantation delamination method.
- the following effects (1) to (6) are obtained.
- Interfacial contact resistance can be reduced by pre-implanting ions on one side of the contact surface between the SiC polycrystalline growth layer and the single-crystal SiC epitaxial growth layer, and performing high-concentration doping control on the other side during film formation. , the ohmic contact resistance can be reduced, and the driving voltage peculiar to the composite substrate can be reduced.
- Thermal CVD enables high-concentration autodoping during the deposition of the SiC polycrystalline growth layer, so the bulk electrical resistance value can be reduced to a level comparable to that of SiC single crystal substrates produced by the sublimation method.
- the first is hydrogen ion implantation for the ion implantation delamination method, and after the ion implantation, hydrogen microbubbles are generated to break the thinned layer.
- An embrittlement thermal anneal is required to facilitate
- the second ion implantation is P ion implantation for reducing the contact interface resistance (ohmic contact) between single crystal SiC and polycrystalline SiC.
- Annealing is required. Both of these annealings are simultaneously achieved by heating the substrate during deposition of the SiC polycrystalline growth layer by CVD, so there is no need to perform these annealing steps separately, making it possible to reduce manufacturing costs.
- (6) Prior to deposition of a thick SiC polycrystalline growth layer by CVD, a delamination phenomenon occurs due to the embrittlement annealing effect. could be suppressed.
- the semiconductor substrate 1 (Second embodiment) (semiconductor substrate) As shown in FIG. 11, the semiconductor substrate 1 according to the second embodiment includes a hexagonal SiC single crystal layer 13I, a SiC epitaxial growth layer 12E arranged on the Si surface of the SiC single crystal layer 13I, A SiC polycrystalline growth layer 18PC is arranged on the C plane facing the Si plane of the SiC single crystal layer 13I.
- the SiC single crystal layer 13I includes a single crystal SiC thinned layer 10HE.
- the monocrystalline SiC thinned layer 10HE comprises a first ion-implanted layer.
- the first ion-implanted layer comprises a hydrogen ion-implanted layer 10HI.
- the monocrystalline SiC thinned layer 10HE comprises an embrittlement layer of the hydrogen ion implanted layer 10HI.
- the SiC single crystal layer 13I may include a second ion-implanted layer.
- the second ion-implanted layer is arranged between the first ion-implanted layer and the SiC polycrystalline growth layer.
- the second ion-implanted layer may comprise a phosphorus ion-implanted layer 10PI.
- the Si plane of the SiC single crystal layer 13I is, for example, the plane of [0001] orientation of 4H-SiC
- the C plane of the SiC single crystal layer 13I is, for example, the [000-1] orientation of 4H-SiC. is the aspect of
- the SiC single crystal substrate 10SB can be reused by being separated from the SiC epitaxial growth layer 12E.
- FIG. 6 shows a cross-sectional view of a structure in which a hydrogen ion-implanted layer 10HI is formed on the Si surface of a SiC single crystal substrate 10SB in the semiconductor substrate manufacturing method according to the second embodiment.
- the hydrogen ion-implanted layer 10HI is weakened by annealing treatment of the hydrogen ion-implanted layer 10HI to form the single-crystal SiC thinned layer 10HE.
- a cross-sectional view of a structure in which a SiC epitaxial growth layer 12E is formed on the Si surface of the thinned layer 10HE is represented as shown in FIG.
- the adhesive 17PI is removed, and the laminate of the single-crystal SiC thinned layer 10HE and the SiC epitaxial growth layer 12E is separated from the graphite substrate 19GS.
- the laminate of the single-crystal SiC thinned layer 10HE and the SiC epitaxial growth layer 12E is mounted so that the Si surface is in contact with the carbon tray 20CT, the C surface is exposed facing upward, and SiC polycrystal growth is performed on the same surface by the CVD method.
- a cross-sectional view of the structure forming layer 18PC is represented as shown in FIG.
- FIG. 1 A cross-sectional view of the structure from which the carbon tray 20CT is removed in the semiconductor substrate manufacturing method according to the second embodiment is shown in FIG.
- an ion implantation delamination method is applied.
- a single crystal SiC thinned layer 10HE is formed from a SiC single crystal substrate 10SB by an ion implantation delamination method.
- the ion implantation delamination method has the following steps.
- the second embodiment is a method of manufacturing a semiconductor substrate 1 having a single crystal SiC thin layer 10HE and a SiC epitaxial growth layer 12E on a SiC polycrystalline growth layer 18PC.
- the substrate bonding method is not used for the interface bonding of the first surface and the second surface.
- the method for manufacturing a semiconductor substrate according to the second embodiment has a step of thinning the (0001) Si plane of the hexagonal SiC single crystal substrate 10SB by an ion implantation delamination method.
- the laminate structure of the SiC single crystal substrate 10SB and the SiC polycrystalline growth layer 18PC is formed without bonding the substrates by a combination technique of the ion implantation delamination method and the CVD direct deposition technique.
- a method for manufacturing a semiconductor substrate can be provided.
- a method for manufacturing a semiconductor substrate according to the second embodiment has the following steps. That is, a step of forming a hydrogen ion-implanted layer 10HI on the Si surface of the SiC single crystal substrate 10SB, a step of forming a SiC epitaxial growth layer 12E on the Si surface of the SiC single crystal substrate 10SB, and embrittlement of the hydrogen ion implanted layer 10HI.
- a step of forming a thin single crystal SiC layer 10HE a step of attaching a temporary substrate to the Si surface of the SiC epitaxial growth layer 12E; , smoothing the surface of the single-crystal SiC thinned layer 10HE that has been stripped, and forming a SiC polycrystalline growth layer 18PC on the surface of the smoothed single-crystal SiC thinned layer 10HE.
- the Si surface of the hexagonal SiC single crystal substrate 10SB is implanted with hydrogen ions for the ion implantation delamination method to have a specified depth (about 1 ⁇ m).
- a hydrogen ion-implanted layer 10HI is formed.
- the acceleration energy is, for example, about 100 keV
- the dose amount is, for example, about 2.0 ⁇ 10 17 /cm 2 .
- the hydrogen ion-implanted layer 10HI is subjected to high temperature treatment to embrittle the hydrogen ion-implanted layer 10HI.
- embrittlement thermal annealing is necessary to generate hydrogen microbubbles and make the thin single-crystal SiC layer 10HE easier to fracture.
- a SiC epitaxial growth layer 12E is formed by homoepitaxial growth on the Si surface of the single-crystal SiC thinned layer 10HE by CVD.
- a temporary substrate is attached to the Si surface of the SiC epitaxial growth layer 12E with an adhesive 17PI.
- a silicon substrate such as a graphite substrate 19GS or a sintered silicon substrate can be applied.
- an organic adhesive such as polyimide is used.
- an organic adhesive such as epoxy or acrylic may be used.
- the C-plane of the single crystal SiC thinned layer 10HE has an average surface roughness Ra of, for example, about 1 nm or less due to the above process.
- the uneven structure of the thin single crystal SiC layer 10HE is exposed.
- the uneven structure of the thin single-crystal SiC layer 10HE is subjected to a mechanical polishing method and a mechanical-chemical polishing method in order to smooth the Si surface of the SiC single-crystal substrate 10SB.
- the Si surface of the SiC single crystal substrate 10SB has an average surface roughness Ra of, for example, about 1 nm or less due to the above process. As a result, the SiC single crystal substrate 10SB can be reused.
- the SiC single crystal substrate 10SB becomes reusable.
- P (phosphorous) ions are implanted into the smoothed surface to reduce the electric resistance value of the contact interface of the stack, forming a phosphorus ion-implanted layer 10PI.
- the depth of the phosphorus ion-implanted layer 10PI is, for example, about 0.01 ⁇ m to 0.5 ⁇ m.
- the acceleration energy is, for example, approximately 10 keV to 180 keV
- the dose amount is, for example, approximately 4.times.10.sup.15/ cm.sup.2 to 6.times.10.sup.16 / cm.sup.2 .
- the adhesive 17PI is removed by wet etching, an organic solvent, or the like to separate the laminate of the thin single-crystal SiC layer 10HE and the SiC epitaxial growth layer 12E from the graphite substrate 19GS. .
- the laminate of the separated single-crystal SiC thinned layer 10HE and the SiC epitaxial growth layer 12E is mounted so that the Si surface is in contact with the carbon tray 20CT, and the C surface faces upward.
- a SiC polycrystalline growth layer 18PC is deposited on the same surface by CVD, and at the same time activation and crystal damage recovery annealing are performed.
- the laminate of the thin single-crystal SiC layer 10HE, the SiC epitaxial growth layer 12E, and the SiC polycrystalline growth layer 18PC is separated from the carbon tray 20CT, and the outer peripheral portion and the substrate are separated. Both sides are processed into a predetermined shape and surface condition.
- the CVD apparatus for forming 18PC may be the same CVD apparatus, or may be configured as separate dedicated apparatuses.
- the semiconductor substrate 1 according to the second embodiment can be formed.
- the substrate bonding method is performed by combining the thinning of the single crystal SiC substrate by the ion implantation delamination method to the Si surface of the hexagonal single crystal SiC substrate and the direct growth of the polycrystalline SiC layer by CVD.
- a single crystal SiC layer and a single crystal SiC layer are obtained by directly depositing a polycrystalline SiC support layer by a CVD method on a single crystal SiC layer thinned to a single crystal layer by using an ion implantation delamination method on the Si surface of a single crystal SiC substrate.
- the manufacturing cost is reduced by eliminating the bonding process of the polycrystalline SiC substrate and simplifying the manufacturing process.
- the second embodiment is a method for manufacturing a SiC composite substrate having a single-crystal SiC epitaxial growth layer on a polycrystalline SiC substrate, wherein the hexagonal single-crystal SiC substrate (000-1) C plane is ion-implanted and delaminated.
- the following effects (1) to (6) are obtained.
- the interfacial contact resistance value can be reduced.
- the driving voltage peculiar to the substrate could be reduced.
- Thermal CVD enables high-concentration autodoping during the deposition of the SiC polycrystalline growth layer, making it possible to reduce the bulk electrical resistance to a level comparable to that of single-crystal substrates produced by sublimation. did.
- the first is hydrogen ion implantation for the ion implantation delamination method, and after the ion implantation, hydrogen microbubbles are generated to form a thin layer.
- An embrittlement thermal anneal is required to facilitate fracturing.
- the second ion implantation is P ion implantation for reducing the contact interface resistance (ohmic contact) between the SiC single crystal substrate and the SiC polycrystalline growth layer.
- An activation thermal anneal is required. Both of these annealings are accomplished simultaneously by heating the substrate during deposition of the SiC polycrystalline growth layer by CVD, so there is no need to perform these annealing steps separately, making it possible to reduce manufacturing costs.
- the semiconductor substrate according to the embodiment can be used, for example, for manufacturing various SiC-based semiconductor devices.
- SiC-SBDs SiC trench gate (T: Trench) type MOSFETs
- SiC planar gate type MOSFETs will be described below.
- the SiC-SBD 21 includes a semiconductor substrate 1 composed of a SiC polycrystalline growth layer (CVD) 18PC and a SiC epitaxial growth layer 12E, as shown in FIG. .
- a SiC single crystal layer 13I may be interposed between the SiC polycrystalline growth layer 18PC and the SiC epitaxial growth layer 12E.
- the SiC single crystal layer 13I suppresses the spread of the depletion layer spreading in the SiC epitaxial growth layer 12E and facilitates the ohmic contact with the SiC polycrystalline growth layer 18PC formed on the C-plane of the SiC epitaxial growth layer 12E. can be formed.
- the SiC epitaxial growth layer 12E becomes a drift layer
- the SiC single crystal layer 13I becomes a buffer layer
- the SiC polycrystalline growth layer 18PC becomes a substrate layer.
- the SiC polycrystalline growth layer 18PC is doped n + type (impurity density is, for example, about 1 ⁇ 10 18 cm ⁇ 3 to about 1 ⁇ 10 21 cm ⁇ 3 ), and the SiC epitaxial growth layer 12E is n ⁇ type ( The impurity density is, for example, about 5 ⁇ 10 14 cm ⁇ 3 to about 5 ⁇ 10 16 cm ⁇ 3 ).
- SiC single crystal layer 13I is doped at a higher concentration than SiC epitaxial growth layer 12E.
- the SiC epitaxial growth layer 12E may have a crystal structure of 4H-SiC, 6H-SiC, or 2H-SiC.
- n-type doping impurities for example, N (nitrogen), P (phosphorus), As (arsenic), etc. can be applied.
- p-type doping impurities for example, B (boron), Al (aluminum), TMA, etc. can be applied.
- the back surface ((000-1)C plane) of the SiC polycrystalline growth layer 18PC is provided with a cathode electrode 22 so as to cover the entire area thereof, and the cathode electrode 22 is connected to the cathode terminal K.
- a surface 100 (for example, (0001) Si plane) of the SiC epitaxial growth layer 12 has a contact hole 24 that exposes a part of the SiC epitaxial growth layer 12E as an active region 23, and a field region 25 surrounding the active region 23. , a field insulating film 26 is formed.
- the field insulating film 26 is made of SiO 2 (silicon oxide), but may be made of other insulators such as silicon nitride (SiN).
- An anode electrode 27 is formed on the field insulating film 26, and the anode electrode 27 is connected to the anode terminal A. As shown in FIG.
- a p-type JTE (Junction Termination Extension) structure 28 is formed in the vicinity of the surface 100 (surface layer portion) of the SiC epitaxial growth layer 12 so as to be in contact with the anode electrode 27 .
- the JTE structure 28 is formed along the contour of the contact hole 24 so as to straddle the inside and outside of the contact hole 24 of the field insulating film 26 .
- trench gate type MOSFET 31 includes semiconductor substrate 1 composed of SiC polycrystalline growth layer 18PC and SiC epitaxial growth layer 12E, as shown in FIG.
- a SiC single crystal layer 13I may be interposed between the SiC polycrystalline growth layer 18PC and the SiC epitaxial growth layer 12E.
- the SiC single crystal layer 13I suppresses the spread of the depletion layer spreading in the SiC epitaxial growth layer 12E and facilitates the ohmic contact with the SiC polycrystalline growth layer 18PC formed on the C-plane of the SiC epitaxial growth layer 12E. can be formed.
- the SiC epitaxial growth layer 12E becomes a drift layer
- the SiC single crystal layer 13I becomes a buffer layer
- the SiC polycrystalline growth layer 18PC becomes a substrate layer.
- the SiC polycrystalline growth layer 18PC is doped n + type (impurity density is, for example, about 1 ⁇ 10 18 cm ⁇ 3 to about 1 ⁇ 10 21 cm ⁇ 3 ), and the SiC epitaxial growth layer 12E is n ⁇ type ( The impurity density is, for example, about 5 ⁇ 10 14 cm ⁇ 3 to about 5 ⁇ 10 16 cm ⁇ 3 ).
- SiC single crystal layer 13I is doped at a higher concentration than SiC epitaxial growth layer 12E.
- the SiC epitaxial growth layer 12E may have a crystal structure of 4H-SiC, 6H-SiC, or 2H-SiC.
- n-type doping impurities for example, N (nitrogen), P (phosphorus), As (arsenic), etc. can be applied.
- p-type doping impurities for example, B (boron), Al (aluminum), TMA, etc. can be applied.
- the back surface ((000-1) C plane) of the SiC polycrystalline growth layer 18PC is provided with a drain electrode 32 so as to cover the entire area thereof, and the drain electrode 32 is connected to the drain terminal D.
- p-type (impurity density is, for example, about 1 ⁇ 10 16 cm ⁇ 3 to about 1 ⁇ 10 19 cm ⁇ 3 ).
- a body region 33 is formed.
- the portion on the side of the SiC polycrystalline growth layer 18PC with respect to the body region 33 is the n ⁇ -type drain region 34 (12E), which remains as the SiC epitaxial growth layer RE.
- a gate trench 35 is formed in the SiC epitaxial growth layer 12E. Gate trench 35 penetrates body region 33 from surface 100 of SiC epitaxial growth layer 12E, and its deepest portion reaches drain region 34 (12E).
- a gate insulating film 36 is formed on the inner surface of the gate trench 35 and the surface 100 of the SiC epitaxial growth layer 12E so as to cover the entire inner surface of the gate trench 35 .
- Gate electrode 37 is buried in gate trench 35 by filling the inside of gate insulating film 36 with, for example, polysilicon.
- a gate terminal G is connected to the gate electrode 37 .
- n + -type source region 38 forming part of the side surface of the gate trench 35 is formed in the surface layer portion of the body region 33 .
- p + -type (impurity density is, for example, about 1 ⁇ 10 18 cm ⁇ 3 to about 1 ⁇ 10 21 cm -3 ) of body contact region 39 is formed.
- An interlayer insulating film 40 made of SiO 2 is formed on the SiC epitaxial growth layer 12E.
- a source electrode 42 is connected to the source region 38 and the body contact region 39 through a contact hole 41 formed in the interlayer insulating film 40 .
- a source terminal S is connected to the source electrode 42 .
- the gate electrode A channel can be formed near the interface with the gate insulating film 36 in the body region 33 by the electric field from 37 . Thereby, a current can flow between the source electrode 42 and the drain electrode 32, and the SiC-TMOSFET 31 can be turned on.
- a planar gate type MOSFET 51 includes a semiconductor substrate 1 composed of a SiC polycrystalline growth layer 18PC and a SiC epitaxial growth layer 12E, as shown in FIG.
- a SiC single crystal layer 13I may be interposed between the SiC polycrystalline growth layer 18PC and the SiC epitaxial growth layer 12E.
- the SiC single crystal layer 13I suppresses the spread of the depletion layer spreading in the SiC epitaxial growth layer 12E and facilitates the ohmic contact with the SiC polycrystalline growth layer 18PC formed on the C-plane of the SiC epitaxial growth layer 12E. can be formed.
- the SiC epitaxial growth layer 12E becomes a drift layer
- the SiC single crystal layer 13I becomes a buffer layer
- the SiC polycrystalline growth layer 18PC becomes a substrate layer.
- the SiC polycrystalline growth layer 18PC is doped n + type (impurity density is, for example, about 1 ⁇ 10 18 cm ⁇ 3 to about 1 ⁇ 10 21 cm ⁇ 3 ), and the SiC epitaxial growth layer 12 is n ⁇ type ( The impurity density is, for example, about 5 ⁇ 10 14 cm ⁇ 3 to about 5 ⁇ 10 16 cm ⁇ 3 ).
- the SiC epitaxial growth layer 12 may have a crystal structure of either 4H-SiC, 6H-SiC, or 2H-SiC.
- n-type doping impurities for example, N (nitrogen), P (phosphorus), As (arsenic), etc. can be applied.
- p-type doping impurities for example, B (boron), Al (aluminum), TMA, etc. can be applied.
- a drain electrode 52 is formed on the back surface ((000-1) C plane) of the SiC single crystal substrate 10SB so as to cover the entire area, and a drain terminal D is connected to the drain electrode 52.
- p-type (impurity density is, for example, about 1 ⁇ 10 16 cm ⁇ 3 to about 1 ⁇ 10 19 cm ⁇ 3 ).
- a body region 53 is formed in a well shape.
- the portion on the SiC single crystal substrate 10SB side with respect to the body region 53 is the n ⁇ -type drain region 54 (12E), which is maintained as it is after the epitaxial growth.
- n + -type source region 55 is formed in the surface layer portion of the body region 53 with a gap from the periphery of the body region 53 .
- a p + -type (impurity density is, for example, about 1 ⁇ 10 18 cm ⁇ 3 to about 1 ⁇ 10 21 cm ⁇ 3 ) body contact region 56 is formed inside the source region 55.
- Body contact region 56 penetrates source region 55 in the depth direction and is connected to body region 53 .
- a gate insulating film 57 is formed on the surface 100 of the SiC epitaxial growth layer 12E.
- the gate insulating film 57 covers the portion of the body region 53 surrounding the source region 55 (periphery of the body region 53 ) and the outer periphery of the source region 55 .
- the gate electrode 58 faces the peripheral portion of the body region 53 with the gate insulating film 57 interposed therebetween.
- a gate terminal G is connected to the gate electrode 58 .
- An interlayer insulating film 59 made of SiO 2 is formed on the SiC epitaxial growth layer 12E.
- a source electrode 61 is connected to the source region 55 and the body contact region 56 through a contact hole 60 formed in the interlayer insulating film 59 .
- a source terminal S is connected to the source electrode 61 .
- the gate electrode A channel can be formed near the interface with the gate insulating film 57 in the body region 53 by the electric field from 58 . Thereby, a current can flow between the source electrode 61 and the drain electrode 52, and the planar gate type MOSFET 51 can be turned on.
- MOS capacitor can also be manufactured using the semiconductor substrate 1 according to the embodiment. MOS capacitors can improve yield and reliability.
- a bipolar transistor can also be manufactured using the semiconductor substrate 1 according to the embodiment.
- the semiconductor substrate 1 according to the embodiment can also be used for manufacturing SiC-pn diodes, SiCIGBTs, SiC complementary MOSFETs, and the like.
- the semiconductor substrate 1 of the present embodiment can also be applied to other types of devices such as LEDs (light emitting diodes) and semiconductor optical amplifiers (SOAs).
- crystal plane 15A and 15B are diagrams illustrating crystal planes of SiC.
- the plan view of FIG. 15A shows the Si surface 211 of the SiC wafer 200 on which the primary orientation flat 201 and the secondary orientation flat 202 are formed.
- the Si plane 211 with the [0001] orientation is formed on the upper surface
- the C plane 212 with the [000 ⁇ 1] orientation is formed on the lower surface.
- a schematic bird's-eye view configuration of a semiconductor substrate (wafer) 1 includes, as shown in FIG. 16, a SiC polycrystalline growth layer 18PC and a SiC epitaxial growth layer 12E.
- the thickness of the SiC polycrystalline growth layer 18PC is, for example, approximately 200 ⁇ m to approximately 500 ⁇ m, and the thickness of the SiC epitaxial growth layer 12E is, for example, approximately 4 ⁇ m to approximately 100 ⁇ m.
- FIG. 17A A schematic bird's-eye view configuration of a 4H—SiC crystal unit cell applicable to the SiC epitaxial growth layer 12E is shown in FIG. 17A, and a schematic configuration of a two-layer portion of the 4H—SiC crystal is shown in FIG. , and the schematic configuration of the four-layer portion of the 4H—SiC crystal is represented as shown in FIG. 17C.
- FIG. 17A A schematic configuration of the unit cell of the 4H—SiC crystal structure shown in FIG. 17A viewed from directly above the (0001) plane is represented as shown in FIG.
- the crystal structure of 4H-SiC can be approximated by a hexagonal system, and four C atoms are bonded to one Si atom.
- the four C atoms are located at the four vertices of a regular tetrahedron centered on the Si atom.
- These four C atoms are arranged such that one Si atom is located on the [0001] axis direction with respect to the C atom and the other three C atoms are located on the [000-1] axis side with respect to the Si atom.
- the off angle ⁇ is, for example, about 4 degrees or less.
- the [0001] axis and [000-1] axis are along the axial direction of the hexagonal prism, and the plane normal to the [0001] axis (the top surface of the hexagonal prism) is the (0001) plane (Si plane). On the other hand, the plane normal to the [000-1] axis (the lower surface of the hexagonal prism) is the (000-1) plane (C plane).
- the directions that are perpendicular to the [0001] axis and pass through non-adjacent vertices of the hexagonal prism when viewed from directly above the (0001) plane are the a1 axis [2-1-10] and the a2 axis, respectively. [-12-10] and a3 axis [-1-120].
- the direction passing through the vertices between the a1 and a2 axes is the [11-20] axis
- the direction passing through the vertices between the a2 and a3 axes is the [-2110] axis
- the direction passing through the vertex between the a3 axis and the a1 axis is the [1-210] axis.
- each of the six axes passing through each vertex of the hexagonal prism the axes that are inclined at an angle of 30° with respect to the axes on both sides thereof and that are normal to each side surface of the hexagonal prism are respectively a1 [10-10] axis, [1-100] axis, [0-110] axis, [-1010] axis, [-1100] axis and [01-10] axis.
- Each plane (side surface of the hexagonal prism) normal to these axes is a crystal plane perpendicular to the (0001) plane and the (000-1) plane.
- the epitaxial growth layer 12E may comprise at least one or more selected from the group of IV group element semiconductors, III-V group compound semiconductors, and II-VI group compound semiconductors.
- the SiC single crystal substrate 10SB and the SiC epitaxial growth layer 12E may be made of any material of 4H-SiC, 6H-SiC, or 2H-SiC.
- the SiC single crystal substrate 10SB and the SiC epitaxial growth layer 12E are selected from the group of GaN, BN, AlN, Al2O3 , Ga2O3 , diamond, carbon, and graphite as materials other than SiC. It may be provided with at least one type that can be used.
- the semiconductor device including the semiconductor substrate according to the embodiment may include any one of GaN-based, AlN-based, and gallium oxide-based IGBTs, diodes, MOSFETs, and thyristors other than SiC-based ones.
- a semiconductor device having a semiconductor substrate has a configuration of one-in-one module, two-in-one module, four-in-one module, six-in-one module, seven-in-one module, eight-in-one module, twelve-in-one module, or four-in-one module. It's okay to be prepared.
- a low-cost SiC polycrystalline growth layer can be used as the substrate material.
- the present embodiment includes various embodiments and the like that are not described here.
- the semiconductor substrate of the present embodiment and the semiconductor device having this semiconductor substrate can be used in various semiconductor module technologies such as IGBT modules, diode modules, and MOS modules (SiC, GaN, AlN, gallium oxide).
- Power modules for inverter circuits that drive electric motors used as power sources for automobiles (including hybrid vehicles), trains, industrial robots, etc. Solar cells, wind power generators and other power generation devices (especially private power generation devices) It can be applied to a wide range of application fields, such as a power module for an inverter circuit that converts the power generated by a power source into the power of a commercial power supply.
- Reference Signs List 1 Semiconductor substrate 10SB SiC single crystal substrate 10HI Hydrogen ion implanted layer 10HE Single crystal SiC thin layer 10PI Phosphorus ion implanted layer 12E SiC epitaxial growth layer 13I SiC single crystal layer 18PC SiC polycrystal growth layer 19GS Graphite Substrate 20CT...Carbon tray 21...Semiconductor device (SiC-SBD) Reference Signs List 22 Cathode electrode 23 Active region 24 Contact hole 25 Field region 26 Field insulating film 27 Anode electrode 28 JTE structure 31 Semiconductor device (SiC-TMOSFET) 32, 52... drain electrodes 33, 53... body regions 34, 54... drain regions 35... gate trenches 36, 57...
- SiC-MOSFET Semiconductor device
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Abstract
Description
(半導体基板)
第1の実施の形態に係る半導体基板1は、図5に示すように、六方晶系のSiC単結晶層13Iと、SiC単結晶層13IのSi面上に配置されたSiCエピタキシャル成長層(SiC-epi)12Eと、SiC単結晶層13IのSi面と対向するC面上に配置されたSiC多結晶成長層(SiC-poly CVD)18PCとを備える。
第1の実施の形態に係る半導体基板の製造方法であって、SiC単結晶基板(SiCSB)10SBのC面に水素イオン注入層10HI及びリンイオン注入層10PIを順次形成した構造の断面図は、図1に示すように表される。
第1の実施の形態に係る半導体基板の製造方法においては、イオン注入剥離法を適用している。イオン注入剥離法により、SiC単結晶基板10SBの表面に単結晶SiC薄化層10HEを形成可能である。イオン注入剥離法は、以下の工程を有する。
(1)従来のイオン注入剥離法を用いた複合基板の製造に必要な基板接合を用いないため、接合起因の接合欠陥やボイドによる歩留り低下を解消できた。また、工数削減及び不良起因の固定費と変動費損失の削減、並びに生産性と品質が向上した。
(2)接合性を確保するための精密な研磨加工が不要となり、不良損失や加工コスト増加による高コスト化が解消し、安価なSiC複合基板の提供が可能となった。
(3)SiC多結晶成長層と単結晶SiCエピタキシャル成長層の接触面の片側に予めイオン注入を行い、もう一方には成膜時に高濃度ドーピング制御を行うことにより、界面接触抵抗値を低減できるため、オーミックコンタクト抵抗を低減可能であり、複合基板特有の駆動電圧を低減できた。
(4)熱CVD法はSiC多結晶成長層の堆積中に、高濃度オートドーピングが可能なため、バルクの電気抵抗値が、昇華法で作製したSiC単結晶基板に匹敵する低抵抗化を可能にした。
(5)SiC単結晶基板C面への2回のイオン注入のうち、1回目はイオン注入剥離法のための水素イオン注入であり、イオン注入後には水素マイクロバブルを発生させ薄化層を破断しやすくするための脆化熱アニールが必要である。2回目のイオン注入は、単結晶SiCと多結晶SiCの接触界面抵抗低減(オーミックコンタクト)のためのPイオン注入であり、注入後にはPイオンを活性化しドナー密度を向上するための活性化熱アニールが必要である。この双方のアニールは、CVDによるSiC多結晶成長層の堆積時の基板加熱により同時に達成されるので、これらアニール工程を別途行う必要が無く、製造コスト低減が可能となった。
(6)CVDによるSiC多結晶成長層の厚膜堆積前に、脆化アニール効果による剥離現象が発生するため、SiC単結晶基板とSiC多結晶成長層の熱膨張係数ミスマッチを緩和し、反りを抑制することができた。
(半導体基板)
第2の実施の形態に係る半導体基板1は、図11に示すように、六方晶系のSiC単結晶層13Iと、SiC単結晶層13IのSi面上に配置されたSiCエピタキシャル成長層12Eと、SiC単結晶層13IのSi面と対向するC面上に配置されたSiC多結晶成長層18PCとを備える。
第2の実施の形態に係る半導体基板の製造方法であって、SiC単結晶基板10SBのSi面に水素イオン注入層10HIを形成した構造の断面図は、図6に示すように表される。
第2の実施の形態に係る半導体基板の製造方法においては、イオン注入剥離法を適用している。イオン注入剥離法により、SiC単結晶基板10SBから単結晶SiC薄化層10HEを形成している。イオン注入剥離法は、以下の工程を有する。
(1)従来のイオン注入剥離法を用いた複合基板の製造に必要な基板接合を用いないため、接合起因の接合欠陥やボイドによる歩留り低下を解消できた。また、工数削減及び不良起因の固定費と変動費損失の削減、並びに生産性と品質が向上した。
(2)接合性を確保するための精密な研磨加工が不要となり、不良損失や加工コスト増加による高コスト化が解消し、安価なSiC複合基板の提供が可能となった。
(3)SiC多結晶成長層とSiCエピタキシャル成長層の接触面の片側に予めイオン注入を行い、もう一方には成膜時に高濃度ドーピング制御を行うことにより、界面接触抵抗値を低減できるため、複合基板特有の駆動電圧を低減できた。
(4)熱CVD法はSiC多結晶成長層の堆積中に、高濃度オートドーピングが可能なため、バルクの電気抵抗値が、昇華法で作製した単結晶基板に匹敵する低抵抗化を可能にした。
(5)SiC単結晶基板のC面への2回のイオン注入のうち、1回目はイオン注入剥離法のための水素イオン注入であり、イオン注入後には水素マイクロバブルを発生させ薄化層を破断しやすくするための脆化熱アニールが必要である。2回目のイオン注入は、SiC単結晶基板とSiC多結晶成長層の接触界面抵抗低減(オーミックコンタクト)のためのPイオン注入であり、注入後にはPイオンを活性化しドナー密度を向上するための活性化熱アニールが必要である。この双方のアニールは、CVDによるSiC多結晶成長層の堆積時の基板加熱により同時に達成されるので、これらアニール工程を別途行う必要が無く、製造コスト低減が可能となった。
(6)Si面をイオン注入剥離法で薄化する第2の実施の形態において、SiC多結晶成長層の堆積の際にSiC単結晶基板自体をCVD反応室に入れる必要がないため、SiC単結晶基板の再利用回数を増加できるため、さらなるコスト低減が可能となった。
実施の形態に係る半導体基板を用いて作製した半導体装置として、SiC-SBD21は、図12に示すように、SiC多結晶成長層(CVD)18PCとSiCエピタキシャル成長層12Eとからなる半導体基板1を備える。尚、SiC多結晶成長層18PCとSiCエピタキシャル成長層12Eとの間に、SiC単結晶層13Iを介在させても良い。ここで、SiC単結晶層13Iにより、SiCエピタキシャル成長層12E中に広がる空乏層の広がりを抑制し、かつSiCエピタキシャル成長層12EのC面に形成されるSiC多結晶成長層18PCとのオーミックコンタクトを容易に形成することができる。SiCエピタキシャル成長層12Eはドリフト層、SiC単結晶層13Iはバッファ層、SiC多結晶成長層18PCはサブストレート層となる。
実施の形態に係る半導体基板を用いて作製した半導体装置として、トレンチゲート型MOSFET31は、図13に示すように、SiC多結晶成長層18PCとSiCエピタキシャル成長層12Eとからなる半導体基板1を備える。尚、SiC多結晶成長層18PCとSiCエピタキシャル成長層12Eとの間に、SiC単結晶層13Iを介在させても良い。ここで、SiC単結晶層13Iにより、SiCエピタキシャル成長層12E中に広がる空乏層の広がりを抑制し、かつSiCエピタキシャル成長層12EのC面に形成されるSiC多結晶成長層18PCとのオーミックコンタクトを容易に形成することができる。SiCエピタキシャル成長層12Eはドリフト層、SiC単結晶層13Iはバッファ層、SiC多結晶成長層18PCはサブストレート層となる。
実施の形態に係る半導体基板1を用いて作製した半導体装置として、プレーナゲート型MOSFET51は、図14に示すように、SiC多結晶成長層18PCとSiCエピタキシャル成長層12Eとからなる半導体基板1を備える。尚、SiC多結晶成長層18PCとSiCエピタキシャル成長層12Eとの間に、SiC単結晶層13Iを介在させても良い。ここで、SiC単結晶層13Iにより、SiCエピタキシャル成長層12E中に広がる空乏層の広がりを抑制し、かつSiCエピタキシャル成長層12EのC面に形成されるSiC多結晶成長層18PCとのオーミックコンタクトを容易に形成することができる。SiCエピタキシャル成長層12Eはドリフト層、SiC単結晶層13Iはバッファ層、SiC多結晶成長層18PCはサブストレート層となる。
図15A及び図15Bは、SiCの結晶面を説明する図である。図15Aの平面図には1次オリフラ(orientation flat)201及び2次オリフラ202が形成されたSiCウェハ200のSi面211が示されている。図15Bの[-1100]の方位から見た側面図では、上面に[0001]の方位のSi面211が形成され、下面に[000-1]の方位のC面212が形成されている。
SiCエピタキシャル成長層12Eに適用可能な4H-SiC結晶のユニットセルの模式的鳥瞰構成は、図17Aに示すように表され、4H-SiC結晶の2層部分の模式的構成は、図17Bに示すように表され、4H-SiC結晶の4層部分の模式的構成は、図17Cに示すように表される。
上記のように、いくつかの実施の形態について記載したが、開示の一部をなす論述及び図面は例示的なものであり、限定するものであると理解すべきではない。この開示から当業者には様々な代替実施の形態、実施例及び運用技術が明らかとなろう。
10SB…SiC単結晶基板
10HI…水素イオン注入層
10HE…単結晶SiC薄化層
10PI…リンイオン注入層
12E…SiCエピタキシャル成長層
13I…SiC単結晶層
18PC…SiC多結晶成長層
19GS…黒鉛基板
20CT…カーボントレイ
21…半導体装置(SiC-SBD)
22…カソード電極
23…活性領域
24…コンタクトホール
25…フィールド領域
26…フィールド絶縁膜
27…アノード電極
28…JTE構造
31…半導体装置(SiC-TMOSFET)
32、52…ドレイン電極
33、53…ボディ領域
34、54…ドレイン領域
35…ゲートトレンチ
36、57…ゲート絶縁膜
37、58…ゲート電極
38、55…ソース領域
39、56…ボディコンタクト領域
40、59…層間絶縁膜
41、60…コンタクトホール
42、61…ソース電極
51…半導体装置(SiC-MOSFET)
100…SiCエピタキシャル成長層の表面
200…SiCウェハ
201…1次オリフラ
202…2次オリフラ
211、[S]…Si面
212、[C]…C面
S…ソース端子
D…ドレイン端子
G…ゲート端子
A…アノード端子
K…カソード端子
Claims (18)
- 六方晶系のSiC単結晶層と、
前記SiC単結晶層のSi面上に配置されたSiCエピタキシャル成長層と、
前記SiC単結晶層のSi面と対向するC面上に配置されたSiC多結晶成長層と
を備える、半導体基板。 - 前記SiC単結晶層は、単結晶SiC薄化層を備える、請求項1に記載の半導体基板。
- 前記単結晶SiC薄化層は、第1イオン注入層を備える、請求項2に記載の半導体基板。
- 前記第1イオン注入層は、水素イオン注入層を備える、請求項3に記載の半導体基板。
- 前記単結晶SiC薄化層は、前記水素イオン注入層の脆化層を備える、請求項4に記載の半導体基板。
- 前記SiC単結晶層は、第2イオン注入層を備える、請求項3に記載の半導体基板。
- 前記第2イオン注入層は、前記第1イオン注入層と、前記SiC多結晶成長層との間に配置される、請求項6に記載の半導体基板。
- 前記第2イオン注入層は、リンイオン注入層を備える、請求項6又は7に記載の半導体基板。
- 前記SiC単結晶層の前記Si面は、4H-SiCの[0001]方位の面であり、前記SiC単結晶層の前記Si面に対向するC面は、4H-SiCの[000-1]方位の面である、請求項1~8のいずれか1項に記載の半導体基板。
- 前記SiC単結晶層は、前記SiCエピタキシャル成長層から剥離することで、再利用可能である、請求項1~9のいずれか1項に記載の半導体基板。
- 請求項1~10のいずれか1項に記載の半導体基板を備える、半導体装置。
- 前記半導体装置は、SiCショットキーバリアダイオード、SiC-MOSFET、SiCバイポーラトランジスタ、SiCダイオード、SiCサイリスタ、及びSiC絶縁ゲートバイポーラトランジスタの群から選ばれる少なくとも1種類もしくは複数種類を備える、請求項11に記載の半導体装置。
- SiC単結晶基板のC面に、水素イオン注入層を形成する工程と、
前記SiC単結晶基板のC面に、SiC多結晶成長層を形成する工程と、
前記SiC多結晶成長層を形成する工程と共に、前記水素イオン注入層を脆化して、単結晶SiC薄化層を形成する工程と、
前記SiC単結晶基板から、前記単結晶SiC薄化層及び前記SiC多結晶成長層の第1の積層体を剥離する工程と、
剥離した前記単結晶SiC薄化層の表面を平滑化する工程と、
前記単結晶SiC薄化層の平滑化した表面にSiCエピタキシャル成長層を形成する工程とを有する、半導体基板の製造方法。 - 前記SiC単結晶基板の前記C面に、前記SiC単結晶基板よりも高不純物濃度の高濃度ドープ層を形成する工程を有する、請求項13に記載の半導体基板の製造方法。
- 前記高濃度ドープ層を形成する工程は、リンイオン注入層を形成する工程を有する、請求項14に記載の半導体基板の製造方法。
- SiC単結晶基板のSi面に、水素イオン注入層を形成する工程と、
前記SiC単結晶基板の前記Si面に、SiCエピタキシャル成長層を形成する工程と、
前記SiCエピタキシャル成長層を形成する工程と共に、前記水素イオン注入層を脆化して、単結晶SiC薄化層を形成する工程と、
前記SiCエピタキシャル成長層のSi面に仮基板を貼り付ける工程と、
前記SiC単結晶基板から、前記単結晶SiC薄化層、前記SiCエピタキシャル成長層及び前記仮基板の第2の積層体を剥離する工程と、
剥離した前記単結晶SiC薄化層の表面を平滑化する工程と、
平滑化した前記単結晶SiC薄化層の前記表面にSiC多結晶成長層を形成する工程とを有する、半導体基板の製造方法。 - 前記単結晶SiC薄化層の前記表面に、前記SiC単結晶基板よりも高不純物濃度の高濃度ドープ層を形成する工程を有する、請求項16に記載の半導体基板の製造方法。
- 前記高濃度ドープ層を形成する工程は、リンイオン注入層を形成する工程を有する、請求項17に記載の半導体基板の製造方法。
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Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2002280531A (ja) * | 2001-03-19 | 2002-09-27 | Denso Corp | 半導体基板及びその製造方法 |
WO2012157679A1 (ja) * | 2011-05-18 | 2012-11-22 | ローム株式会社 | 半導体装置およびその製造方法 |
WO2015064256A1 (ja) * | 2013-10-28 | 2015-05-07 | 富士電機株式会社 | 炭化シリコン半導体装置及びその製造方法 |
JP2017055022A (ja) * | 2015-09-11 | 2017-03-16 | 信越化学工業株式会社 | SiC複合基板の製造方法及び半導体基板の製造方法 |
JP2017057102A (ja) * | 2015-09-15 | 2017-03-23 | 信越化学工業株式会社 | SiC複合基板の製造方法 |
JP2017059626A (ja) * | 2015-09-15 | 2017-03-23 | 信越化学工業株式会社 | SiC複合基板の製造方法 |
US20180047619A1 (en) * | 2016-08-11 | 2018-02-15 | Infineon Technologies Ag | Method of manufacturing a template wafer |
JP2018107303A (ja) * | 2016-12-27 | 2018-07-05 | 三菱電機株式会社 | 半導体装置、電力変換装置および半導体装置の製造方法 |
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Patent Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2002280531A (ja) * | 2001-03-19 | 2002-09-27 | Denso Corp | 半導体基板及びその製造方法 |
WO2012157679A1 (ja) * | 2011-05-18 | 2012-11-22 | ローム株式会社 | 半導体装置およびその製造方法 |
WO2015064256A1 (ja) * | 2013-10-28 | 2015-05-07 | 富士電機株式会社 | 炭化シリコン半導体装置及びその製造方法 |
JP2017055022A (ja) * | 2015-09-11 | 2017-03-16 | 信越化学工業株式会社 | SiC複合基板の製造方法及び半導体基板の製造方法 |
JP2017057102A (ja) * | 2015-09-15 | 2017-03-23 | 信越化学工業株式会社 | SiC複合基板の製造方法 |
JP2017059626A (ja) * | 2015-09-15 | 2017-03-23 | 信越化学工業株式会社 | SiC複合基板の製造方法 |
US20180047619A1 (en) * | 2016-08-11 | 2018-02-15 | Infineon Technologies Ag | Method of manufacturing a template wafer |
JP2018107303A (ja) * | 2016-12-27 | 2018-07-05 | 三菱電機株式会社 | 半導体装置、電力変換装置および半導体装置の製造方法 |
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