Method and apparatus for forming silicon nitride film

An apparatus for forming a silicon nitride film, comprising:

• a process container having a process field configured to accommodate a target substrate;
• a support member configured to support the target substrate inside the process field;
• a heater configured to heat the target substrate inside the process field;
• an exhaust system configured to exhaust gas inside the process field;
• a first process gas supply circuit configured to supply a first process gas containing a silane family gas to the process field;
• a second process gas supply circuit configured to supply a second process gas containing a nitriding gas to the process field;
• a surface-treatment gas supply circuit configured to supply a surface-treatment gas containing a nitriding gas to the process field;
• and
• a control section configured to control an operation of the apparatus,
• wherein the control section executes
• depositing a silicon nitride film on a target substrate by CVD in the process field, while supplying the first process gas and the second process gas to the process field, and setting the process field at a first temperature and a first pressure, for a first time period;
• and
• nitriding a surface of the silicon nitride film in the process field, while supplying the surface-treatment gas to the process field without supplying the first process gas, and setting the process field at a second temperature and a second pressure, for a second time period shorter than the first time period.