| 摘要 |
PURPOSE: To evaluate the crystal quality of a silicon wafer by a method wherein the heights of measuring points on the primary surface of the silicon wafer are measured by an atomic force microscope so as to obtain auto-correlation functions represented by a specific formula, values high in correlation are selected out of them, and the surface micro-roughness of the silicon wafer is analyzed. CONSTITUTION: The heights xi (i=1, 2,...N) of measuring points on the primary surface of a silicon wafer from a reference plane are measured by an atomic force microscope to obtain auto-correlation functions Rj represented by a formula I (j=0, 1, 2,...N) (bar x denotes formula II). An optional number of values high in correlation are selected out of auto-correlation functions Rj , and the surface micro-roughness of the silicon wafer is analyzed based on the distances between point Rj0 and selected point Rj of high correlation, whereby the crystal quality of the silicon wafer is evaluated. By this setup, an evaluation is capable of being quickly made in a comparatively short time. |
