| 摘要 |
PURPOSE:To enable to sharply change the flow rate of gas sent from a bubbler sharply by a method wherein the first gas flowing path connected to the bubbler and the second gas flowing path, whereon a fixed quantity of gas is flowed at all times, are provided and the second gas flowing path is connected to the flow-in side and the flow-out side of the valve of the first gas flowing path through the intermediary of the valve. CONSTITUTION:The first gas flowing path 3 connected to a bubbler 1 and the second gas flowing path 4, whereon a fixed quantity of gas flows at all times, are provided and the second gas flowing path 4 connected to the flow-in side and the flow-out side of the bubbler 1 of the first gas flowing path 3 through the intermediary of valves 7 and 8 respectively. The flow rate of gas sent from the bubbler 1 can be sharply changed by switching the valves 7 and 8. For example, when the carrier gas flow rate of the first gas flowing path 3 is set at D and the carrier gas flow rate of the second gas flowing path 4 is set at E, the flow rate of gas sent from the bubbler 1 becomes D during the period F when the valve 7 is closed and the valve 8 is opened. Then, when the valve 7 is opened and the valve 8 is closed, the flow rate of gas sent from the bubbler 1 becomes D+E. Moreover, when the valve 7 is closed and the valve 8 is opened, the flow rate of gas sent from the bubbler 1 becomes D instantaneously. |
