A semiconductor wafer includes a silicon carbide wafer and an epitaxial layer, which is disposed at a surface of the silicon carbide wafer and made of silicon carbide. The semiconductor wafer satisfies a condition that a waviness value is equal to or smaller than 1 micrometer. The waviness value is a sum of an absolute value of a value α and an absolute value of a value β. A highest height among respective heights of a plurality of points with reference to a surface reference plane within a light exposure area is denoted as the value α. A lowest height among the respective heights of the points at the epitaxial layer with reference to the surface reference plane within the light exposure area is denoted as the value β.