A substrate processing method and a semiconductor manufacturing device

A substrate processing method is provided to control the thickness of a layer formed on a substrate by controlling pressure based upon a pressure value after a correction process. A first difference between measurement values of first and second detection parts is obtained wherein the first detection part detects a state of the peripheral part of a substrate and the second detection part detects a state of the central part of the substrate. A second difference between previously stored measurement values of the first and second detection parts is compared with the first difference. When the second difference is different from the first difference, a pressure correction value of a pressure value is calculated based upon the first difference in a coolant gas flow path installed between a process chamber(3) for processing the substrate and a heating apparatus. The pressure value is corrected by the pressure correction value. While the process chamber is heated by the heating apparatus, coolant gas flows to the inside of the coolant gas flow path by a cooling apparatus. Based upon the pressure value after the correction process, a control part(2) controls the heating apparatus and the cooling apparatus to process the substrate. The pressure value can be corrected to control the layer quality of the substrate.