SECONDARY ION MASS SPECTROMETER

摘要

PURPOSE:To maintain the potential on the surface of a sample constant and to improve the accuracy of quantitative performance by detecting the deflecting quantity of an electron beam from an electron gun and then controlling the potential on the surface of a sample to be analyzed by means of a D.C. power source on the basis of a detected output signal. CONSTITUTION:A sample 12 to be analyzed being held in a sample holder 13 is arranged in a vacuum container 15 of an analyzer, then an electron beam is emitted in parallel to the vicinity of the surface of the sample 12 from an electron gun 17. An electron beam detector 18 for detecting the deflecting quan tity of the electron beam 23 is arranged opposing to said electron gun 17 and then a detected signal from said detector 18 is amplified 19 to control a D.C. power source and regulate the output from the power source 20. The primary ions 21 are irradiated from an ion source 11 onto the sample 12 and the mass spectrometry of the secondary ions 22 from the sample 12 is executed by means of a mass spectrometer 14. Here, the potential on the surface of the sample 12 is maintained constant by means of the power source 20 and the accuracy of quantitative performance of the mass spectrometer 14 is improved.