| 摘要 |
PURPOSE: To improve the limit of detection of a minute amount of element by irradiating a silicon wafer with W-Mαcharacteristics X-ray separated by an X-ray diffraction means for X-ray generated by an X-ray generating means and detecting fluorescent X-ray generated from pollutant. CONSTITUTION: When electron beam generated from a filament 12 enters a rotary pair cathode 11, Lα-ray which is characteristic X-ray of W, Mα-ray, and white X-ray are generated. When such a characteristic X-ray 3 enters, for example, an analyzing crystal 13 composed of LiF at an angleθ, only W- Mα-ray, for example, is reflected at the angleθand separated on a crystal plane. The separated W-MαX-ray 4 passes through collimators 14, 15 and enters a silicon wafer 2 at an extremely low angle. Fluorescent X-ray 5 generated from polluted element of the wafer 2 is detected by an X-ray detector 20 to obtain energy spectrum. A proportional amplifier 22 converts it into a pulse signal which is proportional to rise width of a voltage pulse of a preamplifier 21. A pulse-height analyzer 23 performs counting per specific channel to store it in a memory.
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