Surface measuring device, processing device, and surface measuring method

A surface measuring device comprising:

• a stage configured to allow a measurement object to be placed;
• a sensor unit disposed above the stage and configured to be movable relative to the stage;
• a supply unit configured to supply gas to the sensor unit;
• and
• a control unit,
• wherein the sensor unit includes
• first to N-th air sensors each configured to measure a flow rate of the gas supplied from the supply unit when the gas flows through an internal flow path, where N being a natural number of 2 or more,
• a base portion configured to hold the first to N-th air sensors arranged in a row in a first direction along a horizontal direction, and
• first to N-th nozzles communicating with the internal flow paths of the first to N-th air sensors respectively and each provided with a blow-out hole opened toward the stage, and
• wherein the control unit is configured to execute
• first processing of operating the supply unit such that the gas that has flowed through the internal flow paths is blown downward from the blow-out holes of the first to N-th nozzles,
• second processing of operating at least one of the stage and the sensor unit such that the sensor unit scans a surface of the measurement object during operation of the supply unit by the first processing, and
• third processing of calculating a separation distance between each of the first to N-th nozzles and the surface of the measurement object based on a flow rate of the gas measured in each of the first to N-th air sensors during scanning of the sensor unit by the second processing.