END POINT DETECTOR OF CHEMICAL MECHANICAL POLISHING EQUIPMENT

摘要

PURPOSE: An end point detector of chemical mechanical polishing equipment is provided to precisely detect an etch end point, by installing a vacuum pipe on the back surface of a window confronting a refraction mirror so that deionized water is absorbed to change a refractive index of light. CONSTITUTION: A light emitting device(151) irradiates light to detect a predetermined thickness of a layer. The refraction mirror reflects the light irradiated from the light emitting device to a polishing pad(120). The window(155) is formed in a portion of the polishing pad corresponding to the refractive mirror(153) to transmit the light to the outside of the polishing pad. A slurry introducing path is formed on the upper surface facing a wafer carrier. A detecting unit detects the light reflected from a wafer(10) and an etch end point. A deionized water absorbing pipe absorbs drops of the deionized water at a vacuum pressure, penetrating a polishing table(110). One end of the deionized water absorbing pipe is installed on the back surface of the window facing the refractive mirror. A vacuum pump generates vacuum pressure in the deionized water absorbing pipe, connected to the other end of the deionized water absorbing pipe.