Abstract: A silicon carbide ingot manufacturing method and a silicon carbide ingot manufacturing system are provided. The silicon carbide ingot manufacturing method and the silicon carbide ingot manufacturing system may change a temperature gradient depending on the growth of an ingot by implementing a guide which has a tilted angle to an external direction from the interior of a reactor, in an operation to grow an ingot during a silicon carbide ingot manufacturing process.

Abstract: A method for preparing a SiC ingot includes preparing a crucible assembly comprising a crucible body having an internal space, loading a raw material into the internal space of the crucible body and placing a plurality of SiC seed in the internal space of the crucible body at regular intervals spaced apart from the raw material, and growing the SiC ingot from the plurality of SiC seed by adjusting the internal space of the crucible body to a crystal growth atmosphere such that the raw material is vapor-transported and deposited to the plurality of SiC seed. A density of the crucible body may be 1.70 to 1.92 g/cm3.

Abstract: A silicon carbide ingot manufacturing method and a silicon carbide ingot manufacturing system are provided. The silicon carbide ingot manufacturing method and the silicon carbide ingot manufacturing system may change a temperature gradient depending on the growth of an ingot by implementing a guide which has a tilted angle to an external direction from the interior of a reactor, in an operation to grow an ingot during a silicon carbide ingot manufacturing process.

Abstract: A method in which a carbonaceous protective film is formed on a rear surface of a single crystal SiC seed, the seed is placed in a reaction container without adhesion, and then single crystal SiC is grown from a SiC raw material on a front surface of the seed allows the seed to grow to a single crystal ingot having a large diameter since the absence of adhesion of the seed to a holder prevents the generation of warps or cracks attributed to a difference in thermal expansion coefficient between the seed and the holder during heating.

Abstract: The wafer having a retardation distribution measured with a light having a wavelength of 520 nm, wherein an average value of the retardation is 38 nm or less, wherein the wafer comprises a micropipe, and wherein a density of the micropipe is 1.5/cm2 or less, is disclosed.

Abstract: The wafer having a retardation distribution measured with a light having a wavelength of 520 nm, wherein an average value of the retardation is 38 nm or less, wherein the wafer comprises a micropipe, and wherein a density of the micropipe is 1.5/cm2 or less, is disclosed.

Abstract: The method of preparing a silicon carbide ingot includes: disposing a raw material and a silicon carbide seed crystal to be separated in a reactor having an internal space; adjusting a temperature, a pressure, and an atmosphere of the internal space for sublimating the raw material and growing the silicon carbide ingot on the silicon carbide seed crystal; and cooling the reactor and retrieving the silicon carbide ingot, wherein the adjusting proceeds in a first inert gas atmosphere having a flow quantity of 100 sccm to 300 sccm, the cooling proceeds in a second inert gas atmosphere having a flow quantity of 1 sccm to 250 sccm, and the reactor has a thermal conductivity of 120 W/mK or less.

Abstract: A method of cleaning a wafer comprises: a scrubbing operation comprising treating a target wafer to be cleaned with a brush at a rotation rate of 200 rpm or less to prepare a brush cleaned wafer; and a cleaning operation comprising cleaning the brush cleaned wafer with a cleaning solution to prepare a cleaned bare wafer, wherein the cleaning operation comprises a first cleaning operation and a second cleaning operation sequentially.

Abstract: A method for preparing a seed crystal including a protective film includes preparing i) a first layer composition of a first binder resin and a first solvent and ii) a second layer composition of a second binder resin, a filler, and a second solvent, applying the first layer composition to the rear surface of a seed crystal to form a first coating layer on the rear surface of the seed crystal and drying the first coating layer to form a first layer on the rear surface of the seed crystal, and applying the second layer composition onto the first layer to form a second coating layer on the first layer, followed by heat treating to form a second layer on the first layer wherein the first layer and the second layer are sequentially disposed on the rear surface of the seed crystal, and wherein the first layer has a thickness corresponding to 30% or less of the distance from the bottom surface of the first layer to the top surface of the second layer.

Abstract: A silicon carbide ingot manufacturing method and a silicon carbide ingot manufacturing system are provided. The silicon carbide ingot manufacturing method and the silicon carbide ingot manufacturing system may change a temperature gradient depending on the growth of an ingot by implementing a guide which has a tilted angle to an external direction from the interior of a reactor, in an operation to grow an ingot during a silicon carbide ingot manufacturing process.

Abstract: The wafer having a retardation distribution measured with a light having a wavelength of 520 nm, wherein an average value of the retardation is 38 nm or less, wherein the wafer comprises a micropipe, and wherein a density of the micropipe is 1.5/cm2 or less, is disclosed.

Abstract: A method for producing an ingot includes loading a raw material comprising a raw material powder having a D50 of 80 ?m or more into a reactor (loading step), controlling the internal temperature of the reactor such that adjacent particles of the raw material powder are interconnected to form a necked raw material (necking step), and sublimating components of the raw material from the necked raw material to grow an ingot (ingot growth step).

Abstract: A wafer having relaxation moduli different by 450 GPa or less, as determined by dynamic mechanical analysis, when loaded to 1 N and 18 N with a loading rate of 0.1 N/min at a temperature of 25° C.

Abstract: A wafer manufacturing method, an epitaxial wafer manufacturing method, and a wafer and epitaxial wafer manufactured thereby, are provided. The wafer manufacturing method enables the manufacture of a wafer with a low density of micropipe defects and minimum numbers of particles and scratches. The epitaxial wafer manufacturing method enables the manufacture of an epitaxial wafer that has low densities of defects such as downfall, triangular, and carrot defects, exhibits excellent device characteristics, and improves the yield of devices.

Abstract: A method of manufacturing a silicon carbide ingot, includes a preparing operation of adjusting internal space of a reactor in which silicon carbide raw materials and a seed crystal are disposed to have a high vacuum atmosphere, a proceeding operation of injecting an inert gas into the internal space, heating the internal space by moving a heater surrounding the reactor to induce the silicon carbide raw materials to sublimate, and growing the silicon carbide ingot on the seed crystal, and a cooling operation of cooling the temperature of the internal space to room temperature. The moving of the heater has a relative position which becomes more distant at a rate of 0.1 mm/hr to 0.48 mm/hr based on the seed crystal.

Abstract: The embodiment relates to a method for preparing a graphite sheet having a high thermal conductivity at a low cost without using an expensive polyimide film.

Abstract: A method of growing a semi-insulating SiC single crystal ingot, the method comprising the steps of: (1) placing a dopant coated with silicon carbide (SiC) and a carbon-based material into a reaction vessel containing a seed crystal fixed thereto; and (2) growing a SiC single crystal on the seed crystal, thereby yielding a high-quality semi-insulating SiC single crystal ingot with a uniform thickness-based doping concentration. In addition, another embodiment relates to a method of growing a semi-insulating silicon carbide single crystal ingot, the method comprising the steps of: (a) placing in a reaction vessel, a composition comprising a carbon-containing polymer resin, a solvent, a dopant, and silicon carbide (SiC); (b) solidifying the composition; and (c) growing a SiC single crystal ingot on a seed crystal fixed to the reaction vessel, thereby yielding a high-quality semi-insulating SiC single crystal ingot with a uniform thickness-based doping concentration.

Abstract: A silicon carbide ingot producing method is provided. The method produces a silicon carbide ingot in which an internal space of a reactor is depressurized and heated to create a predetermined difference in temperature between upper and lower portions of the internal space. The method produces a silicon carbide ingot in which a plane of a seed crystal corresponding to the rear surface of the silicon carbide ingot is lost minimally. Additionally, the method produces a silicon carbide ingot with few defects and good crystal quality.

Abstract: An epitaxial wafer including a wafer having one surface and an other surface, and an epitaxial layer formed on the one surface of the wafer, wherein a roughness skewness (Rsk) of the one surface is ?3 nm to 3 nm, and a roughness average (Ra) of an edge area of the one surface is different from that of a central area of the one surface by ?2 nm to 2 nm when the edge area of the one surface is defined as an area between 13.3% and 32.1% of the radius of the wafer in a direction from the edge of the one surface toward the center thereof and the central area of the one surface is defined as an area at 9.4% of the radius of the wafer from the center of the one surface.

Abstract: An apparatus for producing an ingot includes a crucible body having an opening and in which raw materials are accommodated, and a lid assembly located at the opening and having a portion fixed to the crucible body. The lid assembly includes a placement hole having open upper and lower ends, a frame member arranged along a periphery of the opening while surrounding a periphery of the placement hole, and a core member located in the placement hole and movable upward and downward with respect to the frame member.