US3775630A - Electron gun device of field emission type - Google Patents

Electron gun device of field emission type Download PDF

Info

Publication number
US3775630A
US3775630A US00272809A US3775630DA US3775630A US 3775630 A US3775630 A US 3775630A US 00272809 A US00272809 A US 00272809A US 3775630D A US3775630D A US 3775630DA US 3775630 A US3775630 A US 3775630A
Authority
US
United States
Prior art keywords
anode
electron gun
gun device
electrode
field emission
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US00272809A
Other languages
English (en)
Inventor
Y Minamikawa
T Komoda
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hitachi Ltd
Original Assignee
Hitachi Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hitachi Ltd filed Critical Hitachi Ltd
Application granted granted Critical
Publication of US3775630A publication Critical patent/US3775630A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J3/00—Details of electron-optical or ion-optical arrangements or of ion traps common to two or more basic types of discharge tubes or lamps
    • H01J3/02—Electron guns
    • H01J3/021—Electron guns using a field emission, photo emission, or secondary emission electron source

Definitions

  • ABSTRACT An electron gun device of the field emission type comprising an electron emitting cathode tip, a filament for heating the cathode tip, an anode, and a charged particle emitting electrode, in which charged particles are emitted from the electrode and bombard the anode surface to outgas the anode.
  • This invention relates to an improvement in the anode heating system of a field emission type electron gun device and more particularly to a field emission type electron gun device in which the anode is outgassed by a beam of charged particles.
  • FIG. 1 A conventional electron gun device of the field emission type is shown in FIG. 1 in cross-sectional view.
  • a flashing filament l is arranged to heat a cathode tip of a needle shape 2 for improving the electron emission efficiency.
  • the cathode tip of needle shape 2 has a sharpened head and is fixed to the flashing filament 1.
  • An anode is indicated by numeral 3.
  • Electrons 4 are emitted from the top end of the cathode tip 2 by applying a high voltage between the cathode tip 2 and the anode 3 from a high voltage source (not shown).
  • a part of the electrons 5 transmits through an aperture 6 of the anode 3 and is introduced into the lower part of the device, and will be referred to as effective electrons.
  • a support 7 supports the flashing filament I.
  • An infrared lamp 8 is supported by a support 9 and heats the anode 3.
  • the lamp 8 is supplied power from a source 10. It is required for emitting electrons from the cathode tip 2 that the inside of the device is maintained at an ultra high vacuum in the order of l X 10" Torr and that a high electric field in the order of 3 to 6 X 10 V/cm is applied to the top end of the cathode tip 2.
  • a high electric field in the order of 3 to 6 X 10 V/cm is applied to the top end of the cathode tip 2.
  • those except the effective electrons bombard the anode 3. If there are absorbed gas molecules on said anode, the absorbed gas molecules are released and ionized by said electrons 4.
  • an infrared lamp 8 has been conventionally provided near the anode 3 and preliminarily excited to heat the anode 3 to remove absorbed gas molecules.
  • a current is directly allowed to flow through the anode 3. In these cases, an infrared lamp of large capacity or a large current is necessary for this heating since the heat capacity of a field emission type electron gun device is large.
  • An object of this invention is to provide in an electron gun device of the field emission type including a cathode tip of needle shape, a filament for heating said cathode tip, an anode, and means for applying an electric voltage between said cathode tip and said anode to establish an electric field therebetween which causes electrons to be emitted from said cathode tip toward said anode, an improvement comprising means for emitting a beam of charged particles toward the surface of said anode, means for supporting said charged particle emission means, and power source means for supplying a heating current to said charged particle emission means.
  • a field emission type electron gun device of an excellent electron emission efficiency and stable operation in which the electron source is prevented from being damaged with only a small heating power by heating the anode with charged particles emitted from a charged particle emitting electrode.
  • An embodiment comprises an electron source, an anode, and a charged particle emitting electrode, in which charged particles emitted from said charged particle emitting electrode are accelerated by the electric voltage applied between the anode and said electrode and heat said anodeby the collision.
  • FIG. 1 is a cross-sectional view of a conventional electron gun device of the field emission type.
  • FIG. 2 is a cross-sectional view of an embodiment of an electron gun device of the field emission type according to the invention.
  • FIG. 3 is a cross-sectional view of another embodiment of an electron gun device of the field emission type according to the invention.
  • FIG. 2 An embodiment of a field emission type electron gun device according to the invention is shown in FIG. 2, in which in place of the infrared lamp 8 of the conventional device shown in FIG. 1 a hot cathode such :as a thermal electron emitting filament 11 is mounted on a supporting member 9 opposing to the anode 3.
  • a current is supplied from a souce 10 to said hot cathode to heat the cathode.
  • a negative voltage V is applied between the anode 3 and the hot cathode 11 by a dc. source 12.
  • the portion of the anode 3 which is to be bombarded by electrons 4 is locally heated by electrons emitted from said hot cathode 11 and accelerated by the voltage V to exhaust the gas absorbed on the anode 3.
  • FIG. 3 shows another embodiment in which a thermal electron emitting filament 11 is mounted unitarily to the same base 13 as the flashing filament 1 to enhance the replacement of the thermal electron emitting filament 11 in case of a cut of the filament 11.
  • a thermal electron emitting filament can be provided for each flashing filament or tip portion even in case of a field emission type electron gun device having a plurality of flashing filaments or tips.
  • a hot cathode is used as the charged particle emitting electrode, but an ion source may also be employed in place of said hot cathode to obtain similar effects.
  • the anode surface can be effectively and locally heated by charged particles.
  • the total dimension of a device can be reduced and also gas molecules absorbed on the anode can be preliminarily and effectively removed. Therefore, the number of ions colliding with the tip decreases, hence the lifetime of the tip is elongated and simultaneously the stability of the field emission of electrons is improved.
  • an electron gun device of the field emission type including a cathode tip of a needle shape, a filament for heating said cathode tip, an anode, and means for applying an electric voltage between said cathode tip and said anode to establish an electric field therebetween which causes electrons to be emitted from said cathode tip toward said anode, the improvement comprising means for emitting a beam of charged particles toward the surface of said anode, means for supporting said charged particle emission means, and power source means for supplying a required power to said charged particle emitting means.
  • said charged particle emitting means includes an electrode for emitting electrons.
  • An electron gun device further comprising a voltage source connected between said electrode and said anode for applying accelerating voltage for electrons emitted from said electrode therebetween.

Landscapes

  • Electron Sources, Ion Sources (AREA)
US00272809A 1971-07-19 1972-07-18 Electron gun device of field emission type Expired - Lifetime US3775630A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP5315971A JPS5318862B1 (enrdf_load_stackoverflow) 1971-07-19 1971-07-19

Publications (1)

Publication Number Publication Date
US3775630A true US3775630A (en) 1973-11-27

Family

ID=12935051

Family Applications (1)

Application Number Title Priority Date Filing Date
US00272809A Expired - Lifetime US3775630A (en) 1971-07-19 1972-07-18 Electron gun device of field emission type

Country Status (2)

Country Link
US (1) US3775630A (enrdf_load_stackoverflow)
JP (1) JPS5318862B1 (enrdf_load_stackoverflow)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2417179A1 (fr) * 1978-02-08 1979-09-07 Hitachi Ltd Canon electronique a emission de champ
US4467240A (en) * 1981-02-09 1984-08-21 Hitachi, Ltd. Ion beam source
US4560907A (en) * 1982-06-25 1985-12-24 Hitachi, Ltd. Ion source
US4596942A (en) * 1983-06-17 1986-06-24 National Institute For Researches In Inorganic Materials Field emission type electron gun
US5587720A (en) * 1991-11-08 1996-12-24 Fujitsu Limited Field emitter array and cleaning method of the same
CN102651295A (zh) * 2011-02-22 2012-08-29 Fei公司 稳定冷场发射电子源
WO2023117173A1 (en) * 2021-12-21 2023-06-29 ICT Integrated Circuit Testing Gesellschaft für Halbleiterprüftechnik mbH Electron microscope, electron source for electron microscope, and methods of operating an electron microscope

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3678333A (en) * 1970-06-15 1972-07-18 American Optical Corp Field emission electron gun utilizing means for protecting the field emission tip from high voltage discharges

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5854441B2 (ja) * 1976-07-01 1983-12-05 株式会社東芝 着色投光装置

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3678333A (en) * 1970-06-15 1972-07-18 American Optical Corp Field emission electron gun utilizing means for protecting the field emission tip from high voltage discharges

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2417179A1 (fr) * 1978-02-08 1979-09-07 Hitachi Ltd Canon electronique a emission de champ
US4467240A (en) * 1981-02-09 1984-08-21 Hitachi, Ltd. Ion beam source
US4560907A (en) * 1982-06-25 1985-12-24 Hitachi, Ltd. Ion source
US4596942A (en) * 1983-06-17 1986-06-24 National Institute For Researches In Inorganic Materials Field emission type electron gun
US5587720A (en) * 1991-11-08 1996-12-24 Fujitsu Limited Field emitter array and cleaning method of the same
CN102651295A (zh) * 2011-02-22 2012-08-29 Fei公司 稳定冷场发射电子源
EP2492949A3 (en) * 2011-02-22 2014-01-22 FEI Company Stable cold field emission electron source
US8736170B1 (en) 2011-02-22 2014-05-27 Fei Company Stable cold field emission electron source
CN102651295B (zh) * 2011-02-22 2016-08-10 Fei公司 稳定冷场发射电子源
WO2023117173A1 (en) * 2021-12-21 2023-06-29 ICT Integrated Circuit Testing Gesellschaft für Halbleiterprüftechnik mbH Electron microscope, electron source for electron microscope, and methods of operating an electron microscope

Also Published As

Publication number Publication date
JPS5318862B1 (enrdf_load_stackoverflow) 1978-06-17

Similar Documents

Publication Publication Date Title
US4061944A (en) Electron beam window structure for broad area electron beam generators
US4019077A (en) Field emission electron gun
JPS60170141A (ja) イオン源装置
US3775630A (en) Electron gun device of field emission type
US20020185607A1 (en) Ion source filament and method
EP4372782A2 (en) Ion source cathode
US3610985A (en) Ion source having two operative cathodes
TW202027119A (zh) 具有圓柱狀電弧室的間接加熱式陰極離子源
US3448315A (en) Ion gun improvements for operation in the micron pressure range and utilizing a diffuse discharge
CN106508075B (zh) 热阴极等离子体电子枪
US2919380A (en) Electron discharge devices
US4596942A (en) Field emission type electron gun
JP2002318300A (ja) 電子線発生装置
US3748365A (en) Electron beam heating system
RU2035790C1 (ru) Полый катод плазменного эмиттера ионов
US3846663A (en) Electron gun device having a field emission cathode tip protected from destruction due to ion impingement
JPH0766760B2 (ja) 収束性高速原子線源
US4886992A (en) Electron source with magnetic means
JPS5823164Y2 (ja) デンカイホウシユツガタデンシジユウ
US3521113A (en) Electron beam apparatus incorporating a hollow pyramidal indirectly heated cathode member
JPH01248446A (ja) 電界放射形電子銃
RU2159478C2 (ru) Способ изготовления катода с автоэлектронной эмиссией, катод с автоэлектронной эмиссией и устройство автоэлектронной эмиссии
JP2007317491A (ja) クラスターのイオン化方法及びイオン化装置
JP3154018B2 (ja) イオン源
JPS594045Y2 (ja) 薄膜生成用イオン化装置