PURPOSE: To realize uniform characteristics by providing a plurality of gas supply controllers which control the flow rates or pressures of gas supplied inside a chamber separately at a central area and a peripheral area.

CONSTITUTION: A plurality of gas supply controllers 9A, 9B are provided which control the flow rates or pressures of gas supplied inside a chamber separately at the central area and the peripheral area of the chamber to make the flow rate of the gas supplied inside the chamber 1 uniform at the central area and the peripheral area of the chamber. That is, by providing a plurality of gas supply controllers 9A, 9B which control a flow rate of gas supplied inside the chamber, the amount of supplied gas changes according to the position in the chamber and the amount of gas supplied to a semiconductor wafer 8 becomes equivalent at the central area and the peripheral area. According to this constitution, uniformity of etching of a semiconductor wafer in the chamber can be improved, thus providing a high-precision semiconductor manufacturing device.