Title:
PLASMA ELECTRON GUN
Document Type and Number:
Japanese Patent JP3032380
Kind Code:
B2
Abstract:
PURPOSE: To provide a high output plasma electron gun by drastically reducing the degree of ion collision with a screen electrode and whereby preventing sputtering of the electrode.
CONSTITUTION: Ions are accelerated in reverse to the direction where an electron beam is extracted, and are advanced to a screen electrode 12 and an orifice 30. The ions collide with a shield electrode 33 provided on the front surface of the screen electrode 12. The shield electrode 33 is sputtered by the ion collision, and the particles thus sputtered of the material of the shield electrode are adhered to the inner surface of an acceleration part wall 26. Since the material of the shield electrode 33 is the same as that of the acceleration part wall 26, the inner surface of a discharging part wall 25 is not contaminated. Since the sputtered particles are not adhered to an insulator 32, the shield electrode 33 and the acceleration part wall 26 are always insulated from a screen electrode, and an electrically floating condition is thus maintained.
More Like This:
| JPH04196039 | ELECTRON GUN |
| JPH02265150 | SHEET PLASMA ION AND ELECTRON SOURCE BY URAMOTO METHOD |
Inventors:
Tadayoshi Otani
Application Number:
JP17424892A
Publication Date:
April 17, 2000
Filing Date:
July 01, 1992
Export Citation:
Assignee:
JEOL Ltd.
International Classes:
H01J37/077; H05H7/08; (IPC1-7): H01J37/077
Domestic Patent References:
| JP63221540A | ||||
| JP458445A |
Attorney, Agent or Firm:
Fujishima Ijima (1 outside)