Thickness/depth measuring apparatus and method for measuring the thickness of a film and the depth of a groove

摘要

A thickness/depth measuring apparatus and method for measuring the thickness of a film forming a lattice-shaped mask and the depth of a groove formed on a workpiece during processing of the workpiece. The thickness/depth measuring apparatus and method provide for irradiating the workpiece with a coherent light beam, controlling the direction for linear polarization of the coherent light beam irradiated onto the workpiece, adjusting the incident angle of the coherent light beam irradiated onto the workpiece in a predetermined angular range, receiving and detecting reflected light reflected by the workpiece at different irradiated incident angles and including higher-order diffracted light; and calculating the thickness of the film and the depth of the groove in accordance with the intensity of the diffracted light detected.