Apparatus and method for measuring shape

摘要

A shape measuring apparatus and a shape measuring method suited for measuring an edge profile of a thin sample such as a semiconductor wafer or the like is provided. A distribution of surface angle and an edge profile of a measurement site is calculated by emitting light at sequentially different angle to the measurement site of a wafer by sequentially switching and lighting a plurality of LEDs each disposed at one of plurality of positions in one plane by an LED driving circuit, obtaining an image data showing a luminance distribution of the reflected light form the measurement site through a camera by a calculator each time light is emitted and, estimating an emitting angle of the light when the luminance of the reflected light becomes peak based on image data and emitting angle of the light corresponding to each LED by the calculator.