RADIOACTIVE THICKNESS MASS MEASURING

Brand	Owner	Address	Description
GAMMAGAGE	VALMET AUTOMATION (CANADA) LTD.	4401 STEELES AVENUE WEST NORTH YORK, ONTARIO M3N 2S4 Canada	RADIOACTIVE THICKNESS AND MASS MEASURING GAUGES AND DEVICES;
	Where the owner name is not linked, that owner no longer owns the brand

Technical Examples

A thickness of a wafer during polishing operation is detected to accurately perform the polishing. A thickness measuring method, which measures the thickness of the wafer of wafer 7 in polishing a surface, comprises the steps of irradiating the thin film-like material during the surface polishing from a backside with probe light, measuring a reflectance spectrum with a dispersion type multi-channel spectroscope using a photodiode array which has particularly high sensitivity to light having a wavelength ranging from 1 to 2.4 ?m, and calculating the thickness on the basis of a wave form of the reflectance spectrum. The surface polishing is performed while the thickness of the wafer 7 is measured by the above-described thickness measuring method, and the polishing is finished when the thickness of the wafer 7 reaches a target thickness.