A semiconductor processing system includes: a semiconductor processing chamber including an electrostatic chuck disposed in a chamber housing, and a first power supplier for supplying first radio frequency (RF) power to an internal electrode disposed in the electrostatic chuck; a voltage measuring device for measuring a voltage corresponding to the first RF power to output a digital signal; and a control device for outputting an interlock control signal to the semiconductor processing chamber, when it is determined that the voltage increases to be within a predetermined reference range based on the digital signal. The electrostatic chuck is configured to enable a wafer to be seated on a surface of the electrostatic chuck.