| 摘要 |
PURPOSE:To prevent incident primary ions from a complex deflection owing to the potential variation in the incidence, and from the variation of the incident angle, and to make the ions hit the sampling face with a good reproducible performance, by furnishing a metallic primary beam guide at the electric field variating area to the ion radiated portion. CONSTITUTION:To collect the secondary ions 6 radiated from a target 2 efficiently and to lead them to the analyzing portion, it is desired to make the target 2 in the ionizing room parallel to an electrode 4 which has a lead out slit, and to make the primary beams 1 project in at an angle about 20 deg. from the secondary ion radiating direction 6. In this case, since the primary particles pass through a lens 5 and the like to focus the secondary ions, they are deflected in the direction up and down. Therefore, a metallic guide 8 given with the same or equivalent potential to the secondary ion accelerating potential is furnished at the passage from the earth potential to a higher voltage portion, to reduce the deflection. The incident face to the guide portion is square to the incident direction of the primary ions as shown in the figure, to prevent the deflection in the incidence.
|
