METHOD FOR IDENTIFYING SURFACE SHAPE OF SPECIMEN, SYSTEMATIC ERROR OF SYSTEM FOR MEASURING THE SAME, AND MOVEMENT ERROR OF MOVING MECHANISM

摘要

PROBLEM TO BE SOLVED: To identify the surface shape of a specimen, systematic error of a measuring system, and movement error of a mechanism for moving the specimen through the use of an area sensor of the measuring system as a shape data acquisition means without using another acquisition means together.;SOLUTION: An integral-degree polynomial z(x,y) is used as a shape true value model indicating the height z of the surface 12 of the specimen at the locations x and y of observation on the surface 12 of the specimen. When the amounts of movements in the x-axis directions and the y-axis direction for moving the specimen in the x-y plane relative to the measuring system are each α and β, computation information on shape computation values z(0,0,x,y) and z(α,β,x,y) before and after the movement from measurement values containing systematic error E(x, y) in the z-direction at the locations x and y of observation of the measuring system is obtained. Such small α and β that movement error is within allowable error are provided to identify all coefficients A_k(y) and b_k of the model, determine the surface shape, and identify E(x,y). Then large α and β are provided to identify the movement error and identify the surface shape after the movement.;COPYRIGHT: (C)2003,JPO