摘要:
A single crystal silicon carbide substrate has a 4H-polytype crystal structure, has with nitrogen atoms doped as a conduction impurity with an atomic concentration of more than 1×1016/cm3, and has a main surface containing a circle having a diameter of 5 cm. The single crystal silicon carbide substrate includes only one of a facet region and a non-facet region. Thus, variation in nitrogen atom concentration in the single crystal silicon carbide substrate can be suppressed.
摘要:
A connected substrate having a supporting portion and first and second silicon carbide substrates is prepared. The first silicon carbide substrate has a first backside surface connected to the supporting portion, a first front-side surface, and a first side surface connecting the first backside surface and the first front-side surface to each other. The second silicon carbide substrate has a second backside surface connected to the supporting portion, a second front-side surface, and a second side surface connecting the second backside surface and the second front-side surface to each other and forming a gap between the first side surface and the second side surface. A filling portion for filling the gap is formed. Then, the first and second front-side surfaces are polished. Then, the filling portion is removed. Then, a closing portion for closing the gap is formed.
摘要:
A first silicon carbide substrate has a first backside surface connected to a supporting portion, a first front-side surface opposite to the first backside surface, and a first side surface connecting the first backside surface and the first front-side surface to each other. A second silicon carbide substrate has a second backside surface connected to the supporting portion, a second front-side surface opposite to the second backside surface, and a second side surface connecting the second backside surface and the second front-side surface to each other and forming a gap between the first side surface and the second side surface. A closing portion closes the gap. Thereby, foreign matters can be prevented from remaining in a gap between a plurality of silicon carbide substrates provided in a combined substrate.
摘要:
A silicon carbide crystal ingot having a surface greater than or equal to 4 inches, having an n-type dopant concentration greater than or equal to 1×1015 atoms/cm3 and less than or equal to 1×1020 atoms/cm3, a metal atom concentration greater than or equal to 1×1014 atoms/cm3 and less than or equal to 1×1018 atoms/cm3, and not exceeding the n-type dopant concentration, and a metal atom concentration gradient less than or equal to 1×1017 atoms/(cm3·mm), a silicon carbide single crystal wafer produced using the ingot, and a method for fabricating the silicon carbide crystal ingot.
摘要:
A method of manufacturing silicon carbide crystal includes the steps of forming silicon carbide crystal on a main surface of a base composed of carbon and removing the base from silicon carbide crystal by oxidizing carbon. According to the manufacturing method, by gasifying the base integrated with the silicon carbide crystal by oxidizing carbon forming the base, the base is removed from the silicon carbide crystal. Therefore, since it is not necessary to apply physical force to the silicon carbide crystal or the base for separating them from each other, occurrence of a defect involved with removal of the base can be suppressed. Therefore, high-quality silicon carbide crystal having fewer defects can be manufactured.
摘要:
A first vertex of a first single-crystal silicon carbide substrate and a second vertex of a second single-crystal silicon carbide substrate abut each other such that a first side of the first single-crystal silicon carbide substrate and a second side of the second single-crystal silicon carbide substrate are aligned. In addition, at least a part of the first side and at least a part of the second side abut on a third side of a third single-crystal silicon carbide substrate. Thus, in manufacturing a semiconductor device including a composite substrate, process fluctuations caused by a gap between the single-crystal silicon carbide substrates can be suppressed.
摘要:
A first single crystal substrate has a first side surface and it is composed of silicon carbide. A second single crystal substrate has a second side surface opposed to the first side surface and it is composed of silicon carbide. A bonding portion connects the first and second side surfaces to each other between the first and second side surfaces, and it is composed of silicon carbide. At least a part of the bonding portion has polycrystalline structure. Thus, a large-sized silicon carbide substrate allowing manufacturing of a semiconductor device with high yield can be provided.
摘要:
A silicon carbide substrate includes a base layer made of silicon carbide, silicon carbide layers made of single-crystal silicon carbide and arranged side by side on the base layer when viewed in plan view, and a filling portion made of silicon carbide and filling a gap formed between the adjacent silicon carbide layers. The filling portion has a surface roughness of not more than 50 μm in RMS value.
摘要:
A method for producing a silicon carbide single crystal substrate according to the present invention includes steps of: (A) preparing a silicon carbide single crystal substrate having a mechanically polished main face; (B) performing chemical mechanical polishing on the main face of the silicon carbide single crystal substrate using a polishing slurry containing abrasive grains dispersed therein to finish the main face as a mirror surface; (C′1) oxidizing at least a part of the main face finished as a mirror surface by a gas phase to form an oxide; and (C′2) removing the oxide.