METHOD FOR DETECTING END POINT OF CHEMICAL MECHANICAL POLISHING(CMP) PROCESS

摘要

PURPOSE: A method for detecting the end point of a CMP(Chemical Mechanical Polishing) process is provided to be capable of improving the reproducibility of the CMP process. CONSTITUTION: The concentration gradation of material of an initial polishing layer or a polishing stop layer is capable of being checked by sensing polishing waste water(16) using a sensor(15). The checked information of the sensor is transformed into data at an EPD(End Point Detection) system(14). When the first material concentration of the initial polishing layer is constant, a polishing process is carried out with an initial polishing process condition. When the first material concentration of the initial polishing layer is reduced, and the second material concentration of the polishing stop layer is increased, the polishing process is carried out under low polishing pressure. When, the first and second material concentration are constant, the polishing process is ended.