POLISHING LIQUID THICKNESS MEASUREMENT APPARATUS, METHOD AND CHEMICAL MECHANICAL POLISHING DEVICE

摘要

A polishing liquid thickness measurement apparatus used for a chemical mechanical polishing (CMP) device is disclosed. The CMP device comprises a polishing head (10), a rotating table (20), a polishing disc (30) disposed on the upper surface of the rotating table (20), and a polishing pad (40) disposed on the upper surface of the polishing disc (30),wherein the polishing pad (40) is opposite to the polishing head (10). The polishing liquid thickness measurement apparatus comprises a distance sensor (50), which is positioned in the polishing disc (30) and used for measuring the distance between the distance sensor (50) and the wafer held on the polishing head (10); a distance transmitter (60), which is arranged in the rotating table (20) and connected with the distance sensor (50), and used for transforming the signal measured by the distance sensor (50) into a standard electric signal; and a processing unit (70), which is connected with the distance transmitter (60) and used for obtaining the standard electric signal so as to achieve the polishing liquid thickness between the polishing head (10) and the polishing pad (40). A chemical mechanical polishing device comprising the polishing liquid thickness measurement apparatus and a measurement method utilizing the polishing liquid thickness measurement apparatus are also disclosed.