Patent ID: 7652224

Claim:
A semiconductor wafer marking apparatus for marking an identification mark on a semiconductor wafer to identify the semiconductor wafer, the apparatus comprising: a laser head unit comprising: a flowcell having a laser radiation region on an upper surface thereof; and a laser source radiating laser energy on the laser radiation region in response to an input current; an optical system focusing the laser energy radiated from the laser source in response to an input current to form a laser beam and radiating the laser beam on the semiconductor wafer; a cooling water reservoir storing cooling water; a pipe that is disposed in the flowcell and connected to an inlet and an outlet of the cooling water reservoir and through which the cooling water flows to maintain the laser radiation region of the flowcell at a constant temperature; a marking interlock system that detects leakage of cooling water from the pipe, an abnormal temperature of the laser radiation region, and an abnormal input current supplied to the laser source, and generates a marking interlock signal to terminate a marking operation of the semiconductor wafer when the marking interlock system detects at least one of the leakage of cooling water from the pipe, the abnormal temperature of the laser radiation region, and the abnormal input current supplied to the laser source; and a marking unit that turns off the laser source to terminate the marking of the semiconductor wafer in response to the marking interlock signal generated by the marking interlock system.