Contamination control method of vapor deposition apparatus and method of producing epitaxial silicon wafer

A contamination control method of a vapor deposition apparatus, comprising:

• loading a monitor wafer into an interior of a chamber of the vapor deposition apparatus;
• consecutively repeating a heat treatment for thermally treating the monitor wafer loaded into the interior of the chamber for a predetermined number of times without unloading the monitor wafer from the chamber;
• unloading the monitor wafer after experiencing the repetition of the heat treatment from the interior of the chamber;
• and
• evaluating a metal-contamination degree of the monitor wafer unloaded out of the chamber,
• wherein the heat treatment comprises:
• a first heat-treatment, in which a hydrogen-chloride-containing gas is not fed into the interior of the chamber but a hydrogen-containing gas is fed into the chamber to thermally treat the monitor wafer in an atmosphere of the hydrogen-containing gas to reduce a vaporized amount of metal adhered on a surface of the monitor wafer and to remove a natural oxide film present on the surface of the monitor wafer;
• and
• a second heat-treatment, in which the hydrogen-chloride-containing gas and the hydrogen-containing gas are fed into the interior of the chamber to thermally treat the monitor wafer in an atmosphere of the hydrogen-chloride-containing gas and the hydrogen-containing gas to activate the surface of the monitor wafer.