Ebara Corporation

Toshimitsu Sasaki

Keita Yagi

Yuki Watanabe

Yoichi Shiokawa

Nachiketa Chauhan

A cleaning method capable of removing abrasive grains adhering to a light passage provided in a polishing table is disclosed. The cleaning method includes: while supplying slurry containing abrasive grains onto a polishing pad supported by a polishing table, placing a substrate in sliding contact with the polishing pad to polish the substrate; during polishing of the substrate, directing light to the substrate through a light passage provided in the polishing table, and causing reflected light from the substrate to pass through the light passage; removing the polished substrate from the polishing pad; and supplying a chemical liquid into the light passage when the substrate is not present on the polishing pad to remove the abrasive grains adhering to the light passage by the chemical liquid.

Cleaning method for optical surface monitoring device

A substrate polishing method capable of reducing an influence of variation in spectrum of reflected light from a substrate, such as a wafer, and determining an accurate film thickness is disclosed. The method includes: polishing a surface of a substrate by pressing the substrate against a polishing pad on a rotating polishing table; producing a spectrum of reflected light from the surface of the substrate each time the polishing table makes one rotation; creating a three-dimensional data containing a plurality of spectra arranged along polishing time; and determining a film thickness of the substrate based on the three-dimensional data.

Polishing method and polishing apparatus

A polishing method capable of improving a spatial resolution of a film-thickness measurement without changing a measuring cycle of a film-thickness sensor and without increasing an amount of measurement data is disclosed. The polishing method includes: rotating a first film-thickness sensor and a second film-thickness sensor together with a polishing table, the first film-thickness sensor and the second film-thickness sensor being located at the same distance from a center of the polishing table; causing the first film-thickness sensor and the second film-thickness sensor to generate signal values indicating film thicknesses at measurement points on a surface of a substrate, while a polishing head is pressing the substrate against a polishing pad on the rotating polishing table, the measurement points being located at different distances from a center of the substrate; and controlling polishing pressure applied from the polishing head to the substrate based on the signal values generated by the first film-thickness sensor and the second film-thickness sensor.

A polishing method which can acquire an actual position of a film-thickness measurement point, and can therefore apply an optimum polishing pressure to a substrate such as a wafer is disclosed. The method includes: causing a substrate detection sensor to generate substrate detection signals in a preset cycle and causing a film-thickness sensor to generate a film-thickness signal at a predetermined measurement point during polishing of the substrate while the substrate detection sensor and the film-thickness sensor are moving across the surface of the substrate; calculating an angle of eccentricity of a center of the substrate relative to a center of the polishing head from the number of substrate detection signals; correcting a position of the predetermined measurement point based on the angle of eccentricity; and controlling polishing pressure at which the polishing head presses the substrate based on the film-thickness signal and the corrected position of the predetermined measurement point.

Growing community of inventors

Tokyo, Japan

Toshimitsu Sasaki