A method for manufacturing a semiconductor wafer includes a carbon layer formation step, a through hole formation step, a feed layer formation step, and an epitaxial layer formation step. In the carbon layer formation step, a carbon layer (71) is formed on a surface of a substrate (70) made of polycrystalline SiC. In the through hole formation step, through holes (71c) are formed in the carbon layer (71) formed on the substrate (70). In the feed layer formation step, a Si layer (72) and a 3C—SiC polycrystalline layer (73) are formed on a surface of the carbon layer (71). In the epitaxial layer formation step, the substrate (70) is heated so that a seed crystal made of 4H—SiC single crystal is formed on portions of the surface of the substrate (70) that are exposed through the through holes (71c), and a close-spaced liquid-phase epitaxial growth of the seed crystal is caused to form a 4H—SiC single crystal layer.