| 摘要 |
PURPOSE:To lengthen the lifetime of a target, by using the various sections of the identical target. CONSTITUTION:The position of a rotary target 10 can be changed in the axial direction. When the position of the target is altered to another one shown by a dotted line in the figure, the position of a ray source to a sample 20 is changed from C to C'. An applied voltage to a deflection plate 17 is set at an appropriate level to change the incident angle of an electron beam 3 to the target as shown by another dotted line to maintain an identical straight path from the position of the ray source toward the sample 20. The track on the target 10 irradiated with the electron beam 3 can thus be changed to lengthen the lifetime of the target. |
