Substrate thickness measuring device, substrate processing system, and substrate thickness measuring method

A substrate thickness measuring device, comprising:

• a substrate holder configured to hold a substrate;
• a thickness measurer configured to measure a thickness of the substrate held by the substrate holder;
• a housing accommodating therein the substrate holder and at least a part of the thickness measurer;
• a temperature measurer configured to measure a temperature inside the housing;
• and
• a controller and a storage storing a computer program, wherein the storage and the computer program are configured, with the controller, to perform operations including:
• when the temperature measured by the temperature measurer is within a preset allowable range:
• carry the substrate into the housing,
• measure the thickness of the substrate by the thickness measurer, and
• calculate, as a corrected thickness, a product of the thickness measured by the thickness measurer and a preset correction coefficient;
• and
• when the temperature measured by the temperature measurer is outside the preset allowable range;
• carry a calibration substrate into the housing instead of the substrate, and
• change a setting of the correction coefficient based on a thickness of the calibration substrate measured by the thickness measurer.