| 摘要 |
PURPOSE:To prevent the decrease in the accuracy of analysis by forming a crater in the circumferential edge part in the region for scanning the surface of a sample. CONSTITUTION:The ion beam released from an ion source 1 is accelerated by an accelerating power source 2 and is converged to a sample by means of lenses 6, 7 of an electrostatic type on which a suitable voltage is impressed from voltage dividers 4, 5. A deflector 9 scans the surface of the sample 8 by deflecting the ion beam. The secondary ion generated from the sample 9 passes an electrode 11 and a magnetic pole 12 and is dispersed according to mass so as to be made incident to a secondary ion detector 13. The ion beam is irradiated to the circumferential edge of the scanning region prior to analysis to form preliminarily a crater in the circumferential edge part, then the secondary ion generated from the circumferential edge part of the scanning region does not stick on the scanning region and therefore the accuracy in analysis is improved. |
