To provide a method of manufacturing semiconductor wafer capable of improving yield by designing a clamping structure of a semiconductor wafer.

In an epitaxial processing process, an annular first wafer holder 2 and a ring plate 3 are used. The first wafer holder 2 is attached coaxially with a susceptor 11 and has a first circular opening 2a provided with a first edge part 21 which is brought into pressing contact with the wafer 1 over the whole periphery of peripheral edge of the main surface 1a of the wafer 1. The ring plate 3 has a second circular opening 3a provided with a second edge part 31 which is brought into pressing contact with the wafer 1 over the whole periphery of the peripheral edge of the back surface 1b of the wafer 1. Therein, the ring plate 3 clamps the wafer 1 in engagement with the first wafer holder 2. In a shrinkage process, the peripheral edge of the wafer 1 is removed such that the wafer 1 becomes a predetermined diameter.