Accurate determination of the thickness or mass per unit area of thin foils and single-crystal wafers for x-ray attenuation measurements

Abstract

The measurement of thickness and a closely related quantity, the mass per unit area of thin specimens was discussed. It was found that the thickness determined by this method which calibrates both the micrometer map and the x-ray map to the reference value obtained from the mass of a known area, is a direct measurement of the amount of material seen by the incident beam. The derived mass attenuation coefficient was independent of the value used for density of the specimen. The technique was demonstrated by absolute measurements of the x-ray mass attenuation coefficient of copper and silver.