Patent ID: 9233347
Filing Date: 2016-01-12
CPC Classification: B01J,G05D,H01L,Y10T

Claim Text:
1. A mixed gas supply device comprising: (a) a plurality of first gas supply lines including flow rate control devices and outlet side switching valves, wherein the plurality of first gas supply lines are arranged in parallel, in which gas outlets of the respective outlet side switching valves communicate with a manifold, wherein the plurality of first gas supply lines supply a relatively high flow rate of gas; and (b) a second gas supply line having a flow rate, the second gas supply line being a single gas line, wherein a gas outlet of the second gas supply line is connected at a position nearer to a mixed gas outlet of the manifold than a gas outlet of any one of the plurality of first gas supply lines such that the flow rate of gas flowing in the second gas supply line is less than the flow rate of gas flowing in any one of the plurality of first gas supply lines, wherein a gas outlet of the first gas supply line has a maximum flow rate of gas greater than the maximum flow rate of gas among the plurality of first gas supply lines and wherein the gas outlet having the maximum flow rate is connected at a position furthest from the mixed gas outlet of the manifold than any one of the plurality of first gas supply lines, wherein an outlet side of a flow rate control device of the second gas supply line and an inlet side of a corresponding outlet side switching valve of the second gas supply line are hermetically connected via an outlet side connecting fitting of the flow rate control device of the second gas supply line and a mounting table having a gas passage, wherein a hole portion is provided at a part of a flow passage at the outlet side connecting fitting, or at a flow passage of the manifold, or the hole portion is provided at a part of the flow passage at the outlet side connecting fitting and at the flow passage of the manifold, and arranged to make the outlet side switching valve of the second gas supply line and a mixed gas flow passage in the manifold communicate with one another to prevent back-diffusion of another gas to an upstream side of the outlet side switching valve of the second gas supply line, or to an upstream side of the flow rate control device of the second gas supply line, and a process chamber connected to the mixed gas outlet of the manifold arranged to perform a gas displacement at a speed sufficient to prevent gas back-diffusion.