| 摘要 |
PURPOSE:To measure trace impurities contained in an extremely shallow part of a sample by setting the energy region of an ion beam at an intermediate region and detecting scattered particles with a semiconductor detector. CONSTITUTION:The output of a semiconductor detector 33 is connected to a high-voltage cable 34 and a current introducing terminal 35 fixed to the wall section of an analysis chamber 13 and further connected to a preamplifier through a high-voltage signal cable 36. The detector 33 is fitted to a rotatable arm 39 and, as the arm 39 is rotated in accordance with a prefixed program, the detector 33 measures energy spectra at every prescribed angle. When the current amount of an ion beam 31 is maintained at a fixed level by monitoring the beam 31 with a charge integrator during the measurement, the intensity distribution of scattered particles around the center of a sample 16 and the two-dimensional information about the energy spectra at each point can be measured in a short time. When the energy of the beam 31 is lowered to a 200keV area, the detector 33 which receives particles scattered by the sample can detect trace impurities contained in an extremely shallow part of the sample 16 near the surface in a short time even when the content is very small. |
