Substrate treating apparatus and substrate treating method using the same

An apparatus for treating a substrate, comprising:

• a stage extending in a first direction, configured to move a substrate in the first direction, and having an air floating system;
• a gripper installed on one side of the stage to grip the substrate;
• a gantry arranged on the stage to extend in a second direction crossing the first direction;
• a head module installed on the gantry and movable in the second direction;
• and
• a displacement sensor installed in the head module and configured to measure a separation distance between the substrate and the stage,
• wherein at a first position, the head module ejects ink to the substrate and the displacement sensor measures a first separation distance between the substrate and the stage,
• at a second position that is different from the first position, the head module ejects ink to the substrate and the displacement sensor measures a second separation distance between the substrate and the stage, and
• at a third position that is different from the first position and the second position, the displacement sensor measures a flatness of the gripper.

A method of treating a substrate, the method comprising:

• providing a stage extending in a first direction and moving a substrate in the first direction;
• providing a head module arranged on the stage to be movable in a second direction crossing the first direction;
• causing, at a first position, a displacement sensor that is installed in the head module to measure a first separation distance between the substrate and the stage;
• causing, at a second position different from the first position, the displacement sensor to measure a second separation distance between the substrate and the stage;
• and
• monitoring a difference between the first separation distance and the second separation distance.