Polishing method, polishing apparatus, and computer-readable storage medium

A polishing apparatus comprising:

• a polishing table configured to support a polishing tool having a polishing surface;
• a table motor configured to rotate the polishing table;
• a polishing head configured to press a substrate against the polishing surface;
• a sensor configured to measure physical quantity;
• and
• a processing system configured to determine whether each of multiple measurement data points is an effective data point during polishing of the substrate and determine a representative measurement value of the physical quantity based on a measurement value of a measurement data point that has been determined to be the effective data point each time the polishing table makes one revolution, the multiple measurement data points being indicative of measurement values of the physical quantity and measuring times at multiple measurement points measured during one revolution of the polishing table,
• wherein the processing system is configured to count the number of measurement data points within a search area and is configured to determine that a determination-target measurement data point is the effective data point when the number of measurement data points within the search area is equal to or more than a threshold value, and
• the search area is defined by a measurement-value range and a time range, the measurement-value range has a predetermined width including a measurement value of the determination-target measurement data point, and the time range has a predetermined width including a measuring time of the determination-target measurement data point.

A computer-readable storage medium storing a program for causing a computer to perform:

• during polishing of a substrate, determining whether each of multiple measurement data points is an effective data point, the multiple measurement data points being indicative of measurement values of physical quantity and measuring times at the multiple measurement points measured by a sensor during one revolution of a polishing table, the sensor being installed in the polishing table supporting a polishing tool having a polishing tool;
• and
• determining a representative measurement value of the physical quantity based on a measurement data point that has been determined to be the effective data point each time the polishing table makes one revolution,
• wherein determining whether each of the multiple measurement data points is the effective data point is performed by counting the number of measurement data points within a search area and determining that a determination-target measurement data point is the effective data point when the number of measurement data points within the search area is equal to or more than a threshold value, and
• the search area is defined by a measurement-value range and a time range, the measurement-value range has a predetermined width including a measurement value of the determination-target measurement data point, and the time range has a predetermined width including a measuring time of the determination-target measurement data point.