Development and characterization of a new instrument for the traceable measurement of areal surface texture

Abstract

Modern manufacturing industry is beginning to benefit greatly from the ability to control the three-dimensional, or areal, structure of a surface. To underpin areal surface manufacturing, a traceable measurement infrastructure is required. In this paper, the development of a new traceable instrument for the measurement of areal surface texture is presented. The instrument uses a two-axis coplanar air-bearing slideway to move the measured surface beneath a stylus probe. The motion of the slideway is measured using linear and angular interferometers. The key to the new instrument is a novel probing system incorporating a cylindrical air-bearing guideway and an electromagnetic system to maintain a constant stylus force on the surface. The deflection of the stylus is measured using a differential plane mirror interferometer thereby minimizing the effect of any error motion in the metrology frame. The uncertainties of the instrument are calculated using a Monte Carlo approach and are evaluated to be 5 nm in the z axis and 16 nm in the x and y axes (all at k = 2). The results are given for the instrument and are compared to results from a traceable profile measuring instrument and a coherence scanning interferometer.