摘要 |
PURPOSE:To enable the accurate measurement of the distribution of impurity concentration in the part of a semiconductor layer by detecting the variation in the amount of ions reflected from the sputtering surface in irradiating ions. CONSTITUTION:A substrate is set up in a microanalyzer: when an SiO2 layer 12 in the substrate surface is irradiated with irradiating ions of constant energy and constant current density, e.g. O<+> by the action of an ion source 1, acceleration tube 2, and ion sorter 3, Si<n+> ions, O<n+> ions, and B<n+> ions are released out of the sputtering surface of the SiO2 layer 12. The O<n+> ions consist of those sputtered from the layer 12 and those of reflected probe ions. These ions are detected by a semiconductor detector 6, and then the distribution of ions at each energy is detected. The distribution of concentration of impurity B<+> from the surface of an Si layer 11 toward the depth can be accurately measured by assuming that the surface under sputtering transfers from the SiO2 layer 12 to the Si layer 11 at a time t0 at which the rate of ion count is varied by a single channel analyzer 20. |