Patent ID: 8651135

Claim:
A mass flow controller comprising: a gas passageway forming member that forms a gas passageway; a flow rate adjusting unit that is disposed in the gas passageway and includes a valve adjusting a flow rate of a gas and an actuator adjusting an opening degree of the valve; an opening degree setting information storage unit that stores opening degree setting information in which an opening degree setting value of the valve, used when a gas flows into the gas passageway with a flow rate defined according to a process procedure before performing the process procedure, is obtained in advance for each process procedure; and a setting unit that acquires the opening degree setting value corresponding to the process procedure from the opening degree setting information storage unit and controls the actuator on the basis of the acquired opening degree setting value, wherein the gas passageway forming member further includes: a gas inlet port, a gas outlet port, a plurality of independent gas passageways that connects the gas inlet port and the gas outlet port to each other, a gas exhaust port that is provided in each gas passageway, a three-way valve that is provided at the position where each gas exhaust port is provided in the gas passageway, and a synchronization unit that synchronizes an opening and closing control of the three-way valves of the gas passageways, wherein each gas passageway is provided with the flow rate adjusting unit and the setting unit, when the three-way valve of the first gas passageway is opened and the three-way valve of another gas passageway is closed, the setting unit of the first gas passageway adjusts the flow rate adjusting unit of the first gas passageway using a first opening degree setting value corresponding to one process procedure acquired from the opening degree setting information storage unit so as to become a first gas flow rate in accordance with the one process procedure, the setting unit of the second gas passageway adjusts the flow rate adjusting unit of the second gas passageway using a second opening degree setting value corresponding to the next process procedure acquired from the opening degree setting information storage unit so that the gas flowing through the second gas passageway has a second gas flow rate, and when the process procedure is switched, the synchronization unit allows only the three-way vale of the second gas passageway to be opened and allows the three-way valve of another gas passageway including the first gas passageway to be closed.