Patent ID: 7906442

Claim:
A gas processing method in an apparatus comprising a chamber for accommodating a target substrate, an in-chamber member disposed inside the chamber, a gas supply system that supplies a process gas containing NH 3 gas and H 2 gas into the chamber, wherein a certain component of the chamber and/or the in-chamber member that is exposed to the process gas contains nickel (Ni), the method comprising: deriving a reference formula representing a relationship between a process temperature inside the chamber and a flow rate ratio of H 2 /NH 3 in the process gas on condition of a certain set threshold of the number of particles generated by supplying the process gas into the process chamber while heating an interior of the process chamber; and then, performing a gas process on the target substrate by supplying the process gas into the process chamber while setting the process temperature at a selected value and setting the flow rate ratio at an application value, wherein the application value of the flow rate ratio is higher than a calculated value of the flow rate ratio obtained by substituting the selected value of the process temperature into the reference formula.