APPARATUS FOR CHECKING MARKING CONDITION

摘要

PURPOSE: An apparatus for checking a marking condition is provided to check a marking condition in real time when a wanted information is marked on a rear surface of a wafer by using a laser. CONSTITUTION: A circuit pattern is formed on a rear surface of a wafer by using a laser beam oscillated in a laser oscillator. A scanner(14) guides the laser beam to reach a predetermined field of the rear surface of the wafer. A dichroic mirror(12) guides the laser beam oscillated in the laser oscillator(10) to be emitted to the scanner(14). A contents marked on the rear surface of the wafer(20) is emitted to a CCD camera(24) by being reflected through the scanner. The CCD camera(24) is arranged in a straight line with the scanner and the dichroic mirror, takes a picture of the contents marked in the rear surface of the wafer(20), converts the same into corresponding image data and outputs the same. A memory(28) stores reference image data of the marked information. A computer(26) compares the image data output from the CCD camera and the reference image data of the memory to check whether the marking quality is good or not. If the quality is bad, the computer(26) stops the oscillation of the laser beam.