A method of controlling a semiconductor process includes performing a semiconductor process using plasma in a chamber including an electrostatic chuck (ESC) on which a wafer is seated, obtaining an ESC voltage supplied to the ESC, an ESC current detected from the ESC, and bias power supplied to a bias electrode in the chamber, while the semiconductor process is being performed in the chamber, and determining whether a discharge has occurred between the ESC and the wafer using at least one of the ESC voltage, the ESC current, and the bias power.