PURPOSE: To prevent that fine dust particles fly down to the surface of a semiconductor wafer when the supply and evacuation operation for a gas inside a closed chamber is executed ragarding a supply and evacuation apparatus and method which prevent dust particles from being produced inside the closed chamber when the supply and evacuation operation of the closed chamber is executed during the manufacturing process or the like of a semiconductor device by the use of an epitaxial growth apparatus or the like.

CONSTITUTION: An apparatus which evacuates a gas from the inside of a hermetically sealed chamber 1 or which supplies the gas into the inside of the hermetically sealed chamber 1 is constituted so as to be provided with the following: a main supply and evacuation pipe 2 provided with a main supply and evacuation valve 3; an assistant supply and evacuation pipe 4 provided with an assistant supply and evacuation valve 5; a flow-rate adjustment pipe 9 provided with a flow-rate adjustment valve 10; a pump 6 connected individually to the main supply and evacuation pipe 2, the assistant supply and evacuation pipe 4 and the flow-rate adjustment pipe 9; a pressure sensor 7 installed inside the closed chamber 1; and a control device 8 which controls the main supply and evacuation valve 3, the assistant supply and evacuation valve 5 and the flow-rate adjustment valve 10 on the basis of the detection data of the pressure sensor 7.