A semiconductor substrate includes a base portion, an auxiliary layer and a surface layer. The auxiliary layer is formed on the base portion. The surface layer is formed on the auxiliary layer. The surface layer is in contact with a first main surface of the semiconductor substrate. The auxiliary layer has a different electrochemical dissolution efficiency than the base portion and the surface layer. At least a portion of the auxiliary layer and at least a portion of the surface layer are converted into a porous structure. Subsequently, an epitaxial layer is formed on the first main surface.

A composite substrate is provided in some embodiments of the present disclosure, which includes a substrate, an insulation layer, a first silicon-containing layer and a first epitaxial layer. The insulation layer is disposed on the substrate. The first silicon-containing layer is disposed on the insulation layer, in which the first silicon-containing layer includes a plurality of group V atoms. The first epitaxial layer is disposed on the first silicon-containing layer, in which the first epitaxial layer includes a plurality of group III atoms. A distribution concentration of the group V atoms in the first silicon-containing layer increases as getting closer to the first epitaxial layer, and a distribution concentration of the group III atoms in the first epitaxial layer increases as getting closer to the first silicon-containing layer. A method of manufacturing a composite substrate is also provided in some embodiments of the present disclosure.

The present disclosure relates to the technical field of silicon carbide processing, and discloses a method and device for preferential etching of dislocation of a silicon carbide wafer. According to the method and device of the present disclosure, a concentration of the etchant is effectively reduced while the high-temperature etching activity is guaranteed, the dislocations on the carbon surface and the silicon surface of the silicon carbide wafer are exposed, and dislocation etching pits with high distinguishing degree are obtained on the carbon surface and the silicon surface of the silicon carbide wafer and thus identified clearly.

The substrate is doped with P, has a resistivity adjusted to 1.05 mΩ.Math.cm or less, and includes defects, formed in the crystal by the aggregation of P, which are Si—P crystal defects substantially. The method includes a step of forming a silicon oxide film on the backside of the substrate with a thickness of 300 nm or more and 700 nm or less, a step of mirror-polishing the substrate, and after the mirror-polishing step, a heat treatment step of the substrate mounted on a substrate holder made of Si or SiC, on the holder surface a silicon oxide film is formed with the thickness between 200 nm and 500 nm, wherein the thickness X of the silicon oxide film of the holder and the thickness Y of that on the backside of the substrate satisfy a relational expression Y=C−X, where C is a constant between 800 and 1000.

A method for manufacturing epitaxial films with multiple stress states, comprising steps of: providing a first single crystal substrate, and forming a sacrificial layer and a first epitaxial film on the first single crystal substrate, wherein the first epitaxial film is made of a first material;

removing the sacrificial layer to separate the first epitaxial film from the first single crystal substrate; transferring the first epitaxial film to a second single crystal substrate, wherein the second single crystal substrate is made of a second material, a partial surface of the second single crystal substrate being overlapped by the first epitaxial film; applying epitaxies onto the first epitaxial film and the second single crystal substrate to form a second epitaxial film on the first epitaxial film and the second single crystal substrate.

An AlN monocrystal plate disclosed herein may include: a first surface in a thickness direction; and a second surface opposing the first surface. A metal component containing region may be disposed substantially parallel to the first surface in an intermediate portion between the first surface and the second surface. In the metal component containing region, a plurality of metal components may be introduced and distributed. A type of the metal components may be Ga.

A method of forming a semiconductor-on-insulator (SOI) substrate includes: forming a first dielectric layer on a first substrate; forming a buffer layer on a second substrate; forming a semiconductor cap on the buffer layer over the second substrate; forming a cleavage plane in the buffer layer; forming a second dielectric layer on the semiconductor cap after forming the cleavage plane; bonding the second dielectric layer on the second substrate to the first dielectric layer on the first substrate; performing a splitting process along the cleavage plane in the buffer layer; removing a first split buffer layer from the semiconductor cap; and removing a second split buffer layer from the second substrate.

A semiconductor device has a substrate. The substrate can be multiple layers. A first semiconductor layer made of a first semiconductor material is disposed over the substrate. The first semiconductor material can be substantially defect-free silicon carbide. A second semiconductor layer made of a second semiconductor material dissimilar from the first semiconductor material is disposed over the first semiconductor layer. The second semiconductor material is silicon. A third layer can be disposed between the first semiconductor layer and second semiconductor layer. A semiconductor device is formed in the second semiconductor layer. The semiconductor device can be a power MOSFET or diode. The second semiconductor layer with the electrical component provides a first portion of a breakdown voltage for the semiconductor device and the first semiconductor layer and substrate provide a second portion of the breakdown voltage for the semiconductor device.

A semiconductor device has a substrate made of a first semiconductor material. The first semiconductor material is silicon carbide. A first semiconductor layer made of the first semiconductor material is disposed over the substrate. A second semiconductor layer made of a second semiconductor material dissimilar from the first semiconductor material is disposed over the first semiconductor layer. The first semiconductor material is substantially defect-free silicon carbide, and the second semiconductor material is silicon. A semiconductor device is formed in the second semiconductor layer. The semiconductor device can be a power MOSFET, diode, insulated gate bipolar transistor, cluster trench insulated gate bipolar transistor, and thyristor. The second semiconductor layer with the electrical component provides a first portion of a breakdown voltage for the semiconductor device and the first semiconductor layer and substrate provide a second portion of the breakdown voltage for the semiconductor device.

A semiconductor device according to one or more embodiments is disclosed that may include a first substrate comprising a single-crystalline SiC substrate; a second substrate comprising a polycrystalline SiC substrate; and an interface layer sandwiched between the first substrate and the second substrate and comprising at least elements of phosphorus and chromium.