Substrate processing method and substrate processing system using the same

A substrate processing system comprising:

• a nozzle head unit comprising a plurality of nozzles that eject ink droplets on a substrate using an inkjet method;
• and
• an inspection device determining an ink ejection speed of each of the plurality of nozzles based on impacts of ink droplets ejected from the nozzle head unit to the substrate, wherein the inspection device;
• determines a first impact of an ink droplet ejected toward a substrate moving at a first speed;
• determines a second impact of an ink droplet ejected toward the substrate moving at a second speed;
• determines a reference ejection speed based on the first impact and the second impact;
• determines a plurality of third impacts of a plurality of ink droplets respectively ejected from a plurality of nozzles toward the substrate moving at a third speed;
• determines an ink ejection speed of each of the plurality of nozzles based on the first impact and the plurality of third impacts;
• and
• compares the ink ejection speeds of the plurality of nozzles with the reference ejection speed and determining whether ink ejection performance of the plurality of nozzles is abnormal,
• wherein the inspection device, after the determining of whether the ink ejection performance of the plurality of nozzles is abnormal, the inspection device corrects the ink ejection performance by changing voltages applied to each of the plurality of nozzles.