DEVICE AND METHOD FOR DETECTING SUBSTRATE ON POLISHING PAD

• Main Authors: KUBO TOMIO, TAKAOKA KAZUHIRO, KATSUMA MICHIO
• Format: Patent
• Language: English
• Published: 03.08.2006
• Subjects: BASIC ELECTRIC ELEMENTS; DRESSING OR CONDITIONING OF ABRADING SURFACES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS; GRINDING; MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; PERFORMING OPERATIONS; POLISHING; SEMICONDUCTOR DEVICES; TRANSPORTING

PROBLEM TO BE SOLVED: To provide a method for detecting a silicon substrate dislocated from a carrier on a polishing cloth even if the polishing cloth used for polishing the substrate is black. SOLUTION: A predetermined position S1on the polishing cloth 11 is irradiated with first inspection light from a first reflection sensor A apparatus at an angle of 15° from the upper face side of the polishing pad. A first light receiving element signal P1of the quantity of reflected light is compared with a threshold Lw, and an on/off signal is transmitted from a first relay A. At the same time, the predetermined position S1on the polishing cloth 11 is irradiated with second inspection light from a second reflection sensor B apparatus at an angle of 5° from the upper face side of the polishing pad. A second light quantity signal P2of the quantity of reflected light is compared with a threshold Lb, and an on/off signal is transmitted from a second relay B. When the combination of the on/off signals transmitted from the respective relays A, B is the same (on and on), an "on" alarm signal meaning the occurrence of dislocation of the substrate on the polishing pad is output to a sequence of an index head type polishing device 30. COPYRIGHT: (C)2006,JPO&NCIPI