Density comparison measurement of silicon by pressure of flotation method

We have developed a new density comparison measurement system for silicon c rystals using the pressure of flotation method (PFM) to evaluate the consis tency in the absolute densities and to study defect and impurity effects on silicon single crystals. We have carried out density comparison measuremen ts for the density standard and Avogadro constant silicon spheres of the Na tional Research Laboratory of Metrology (NRLM), Ibaraki, Japan. We have cal culated the adjusted densities from our comparison and absolute measurement s based on a least-squares analysis using a matrix formulation.