Method for manufacturing silicon epitaxial wafer

A silicon epitaxial wafer manufacturing method in which a vapor phase growth of a silicon epitaxial layer is performed on a front surface of a silicon single crystal substrate which is subjected to a mirror polishing finished on a rear surface, while heating the silicon single crystal substrate introduced into a reaction chamber comprising:

• etching an inside of the reaction chamber with a hydrogen chloride gas to remove a silicon deposit deposited in the reaction chamber in a state that a silicon single crystal substrate is not introduced in the reaction chamber;
• thereafter performing a primary cooling in the reaction chamber;
• subsequently performing a secondary heating of an inside of the reaction chamber;
• subsequently performing a secondary cooling of the inside of the reaction chamber;
• and
• thereafter introducing a silicon single crystal substrate into the reaction chamber to perform the vapor phase growth;
• and forming a silicon thin film in the reaction chamber by introducing a silicon material gas in the reaction chamber after the etching, which is followed by the primary cooling,
• wherein the hydrogen chloride gas does not exist in the reaction chamber during both of the secondary heating and the secondary cooling.