EP0702388A1 - Eine Verzögerungsleitung enthaltende Schaltungsanordnung für eine Wanderfeldröhre und Verfahren zum Herstellen einer, eine Verzögerungsleitung enthaltenden Schaltungsanordnung - Google Patents

Eine Verzögerungsleitung enthaltende Schaltungsanordnung für eine Wanderfeldröhre und Verfahren zum Herstellen einer, eine Verzögerungsleitung enthaltenden Schaltungsanordnung Download PDF

Info

Publication number
EP0702388A1
EP0702388A1 EP95112960A EP95112960A EP0702388A1 EP 0702388 A1 EP0702388 A1 EP 0702388A1 EP 95112960 A EP95112960 A EP 95112960A EP 95112960 A EP95112960 A EP 95112960A EP 0702388 A1 EP0702388 A1 EP 0702388A1
Authority
EP
European Patent Office
Prior art keywords
dielectric support
slow
wave
base material
support rod
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.)
Granted
Application number
EP95112960A
Other languages
English (en)
French (fr)
Other versions
EP0702388B1 (de
Inventor
Katsuhiro c/o Intellectual Property Div. Gonpei
Hirotshi c/o Intellectual Property Div. Hirata
Katutoshi c/o Intellectual Property Div. Fujita
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.)
Toshiba Corp
Original Assignee
Toshiba Corp
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 Toshiba Corp filed Critical Toshiba Corp
Publication of EP0702388A1 publication Critical patent/EP0702388A1/de
Application granted granted Critical
Publication of EP0702388B1 publication Critical patent/EP0702388B1/de
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
    • H01J23/00—Details of transit-time tubes of the types covered by group H01J25/00
    • H01J23/16—Circuit elements, having distributed capacitance and inductance, structurally associated with the tube and interacting with the discharge
    • H01J23/165—Manufacturing processes or apparatus therefore
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J23/00—Details of transit-time tubes of the types covered by group H01J25/00
    • H01J23/16—Circuit elements, having distributed capacitance and inductance, structurally associated with the tube and interacting with the discharge
    • H01J23/24—Slow-wave structures, e.g. delay systems
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2223/00—Details of transit-time tubes of the types covered by group H01J2225/00
    • H01J2223/16—Circuit elements, having distributed capacitance and inductance, structurally associated with the tube and interacting with the discharge
    • H01J2223/24—Slow-wave structures, e.g. delay systems
    • H01J2223/26—Helical slow-wave structures; Adjustment therefor

Definitions

  • the present invention relates to a slow-wave circuit assembly of a traveling-wave tube known as an electron tube for amplifying a microwave and, more particularly, to a dielectric support rod for supporting a slow-wave line of a slow-wave circuit assembly and a method of manufacturing the dielectric support rod.
  • a traveling-wave tube is an electron tube using an interaction between a focused electron beam and, for example, a microwave propagating through a spiral slow-wave line. More specifically, when the microwave is propagating through the spiral slow-wave line, the microwave interacts with the electron beam adjacent to the spiral slow-wave line to partially transmit the energy of the electron beam to the microwave, thereby amplifying the microwave. For this reason, the microwave applied to the input terminal of the spiral slow-wave line adjacent to a cathode is amplified and appears at the output terminal of the spiral slow-wave line. The microwave is extracted to an external circuit as an amplified microwave output. The electron beam interacting with the microwave is caught by a collector electrode and converted into heat.
  • the elongated spiral slow-wave line is generally inserted in an elongated pipe-like metal vacuum vessel and electrically connected to a conductor, e.g., the central conductor of a coaxial line, having both the ends which respectively receive and output a microwave.
  • a conductor e.g., the central conductor of a coaxial line
  • the spiral slow-wave line is stably supported by, e.g., three dielectric support rods and arranged on the central axis of the vacuum vessel. Therefore, these dielectric support rods are in contact with the inner surface of the vacuum vessel and the outer surface of the spiral slow-wave line at once.
  • beryllium oxide As the material of the dielectric support rods, for the sake of electrical characteristics, mechanical characteristics, thermal characteristics, and the like, beryllium oxide, aluminum oxide, silica or the like is used. Of these materials, although beryllium oxide is poisonous and mechanically brittle, beryllium oxide having good electrical insulation properties, a small dielectric loss, high heat withstanding characteristic, and good heat conduction characteristics is popularly used.
  • boron nitride is being practically used as a dielectric support rod.
  • pyrolytic boron nitride (to be referred to as PBN hereinafter) is used.
  • PBN is mechanically more flexible than beryllium oxide, and has a small dielectric constant and good assembling properties.
  • PBN has a small secondary electron emission coefficient which is 1 or less, the surface of the PBN support rod is easily charged when electrons passing through the PBN support rod partially collide with PBN.
  • An electron beam emitted from the cathode of the traveling-wave tube passes through a hollow space of the spiral slow-wave line by the focusing effect of a magnet arranged outside the traveling-wave tube to reach a collector electrode.
  • the electron beam has a velocity distribution and travels with limited spread, a small number of electrons inevitably collide with the spiral slow-wave line and the dielectric support rods.
  • the collision of electrons and the emission of secondary electrons positively or negatively charge the surface of each dielectric support rod. If the charge amount is considerably large, the traveling-wave tube cannot be normally operated.
  • the traveling path of electron beam is varied by an electrostatic focusing effect or an electrostatic deflection effect, and electrons colliding with the spiral slow-wave line or the dielectric support rod increase in number.
  • the interaction between the microwave and the electron beam is insufficient, and the microwave is not sufficiently amplified.
  • Collision of electrons with the spiral slow-wave line and the dielectric support rod causes increases in charge amount and a current flowing in the spiral slow-wave line.
  • a temperature in the traveling-wave tube increases, and the traveling-wave tube may be broken.
  • the oxide coating for suppressing the surface of the dielectric support rod from being charged is effective in a traveling-wave tube in which a microwave output power is relatively low.
  • the coating when the coating is applied to a high-power traveling-wave tube in which a temperature easily becomes high and the energy of collision of electrons with the dielectric support rod is large, the coating cannot have high reliability.
  • oxide coating When an oxide coating is formed on the surface of the dielectric support rod, changes in oxide coating, e.g., changes in physical and chemical states such as a change in reduction and thickness of the oxide coating or formation of cracks, easily occur due to a high-temperature operation for a long time and an abrupt change in temperature. Therefore, the charge prevention effect may be changed or degraded.
  • the oxide coating may be peeled from the surface of dielectric support rod, and the oxide coating cannot be controlled at high accuracy or stabilized when the oxide coating is formed.
  • a slow-wave circuit assembly for a traveling-wave tube in which an element different from a base material of dielectric support rods for supporting a slow-wave line is implanted into base material surfaces of the support rods to a predetermined depth at a predetermined concentration to decrease a surface electrical resistance to a value smaller than an electrical resistance of the base material.
  • a method of manufacturing a slow-wave circuit assembly comprising the steps of ion-implanting an element different from a base material of dielectric support rods from base material surfaces of the dielectric support rods into the base material to a predetermined depth at a predetermined concentration, and performing annealing for the dielectric support rods in a non-oxidizing atmosphere.
  • the element ion-implanted into the base material of the dielectric support rods to a predetermined depth at a predetermined concentration sets the surface electrical resistance of each dielectric support rod to be lower than the electrical resistance of the base material of the support rod itself, thereby preventing the surface of the support rod in operation from being charged.
  • a stable bond between the base element of the dielectric support rod and the ion-implanted element can be obtained, a change in surface resistance is small, and a stable operation of the traveling-wave tube can be kept.
  • the slow-wave circuit assembly can be manufactured at high accuracy with good reproducibility.
  • FIG. 1A is a schematic sectional side view showing the spiral slow-wave circuit assembly for the traveling-wave tube
  • FIG. 1B is a view illustrating the cross section of a dielectric support rod of the spiral slow-wave circuit assembly.
  • a dielectric support rod of the spiral slow-wave circuit assembly In an elongated pipe-like stainless vacuum vessel 11 in which a vacuum state is set, three dielectric support rods 12 are arranged around the center of the stainless vacuum vessel 11 at an angular interval of 120°, and a slow-wave line 13 obtained by spirally winding, e.g., a molybdenum tape, is supported and fixed inside the dielectric support rods 12.
  • the contact portions of the vacuum vessel, the dielectric support rods, and the slow-wave line are in tight mechanical contact with each other or are brazed to each other to form a heat-conductive path.
  • an electron beam e travels in the central space of the spiral slow-wave line 13 to interact with an electromagnetic wave, i.e., a microwave, thereby amplifying the microwave.
  • each dielectric support rod 12 for supporting the slow-wave line an element different from the base material of the dielectric support rod 12 is implanted into the base material surface to a predetermined depth at a predetermined concentration.
  • An area in which the element is implanted is represented by reference symbol M in FIG. 1B. This area extends from a surface 12a which is in contact with the slow-wave line of the dielectric support rod 12 and both side surfaces 12b to a predetermined depth.
  • various dielectrics ceramics such as a boron nitride (BN) such as the above PBN, beryllia (BeO), alumina (Al2O3), aluminum nitride (AlN), and silicon nitride (Si3N4); quartz (SiO2); and other heat-resistant glass materials, each of which is known as a dielectric for supporting the slow-wave line of a traveling-wave tube can be used.
  • BN boron nitride
  • BeO beryllia
  • Al2O3 aluminum nitride
  • Si3N4 silicon nitride
  • quartz SiO2
  • other heat-resistant glass materials each of which is known as a dielectric for supporting the slow-wave line of a traveling-wave tube
  • an element ion-implanted to decrease a surface electric resistance is an element different from the element constituting the base material of the dielectric support rod.
  • an element except for hydrogen and inert gases such as argon is
  • the first embodiment will be described below in accordance with a preferable manufacturing method.
  • PBN is prepared by the same pyrolytic method as described above.
  • This PBN, as described above, has a hexagonal system, and is layered boron nitride having strong anisotropy as mechanical, thermal, and electrical characteristics.
  • the PBN has a high electrical resistance and a small dielectric loss as characteristic features.
  • the PBN has good heat conductivity and is so mechanically flexible that it is not easily bent.
  • the dielectric support rod 12 using the PBN as a base material is processed into an elongated rod having the cross section shown in FIG. 1A, one side having a width of about 1 mm, and a length of about 150 mm.
  • magnesium (Mg) which is a Group II element in the periodic table, and Mg ions are implanted into the base material surface of the dielectric support rod 12 to a predetermined depth.
  • An ion implantation apparatus is constituted by an ion source, a mass separator, a subsequent acceleration tube, a beam scanner, and an implantation chamber. Mg is evaporated in the ion chamber of the ion source, and the Mg vapor collides with electrons to be ionized. The resultant ions are extracted from the ion chamber to form an ion beam by a focusing effect. Thereafter, the ion beam is guided to the mass separator, and only Mg ions are extracted from the mass separator.
  • the Mg ions are implanted in the PBN base material at an ion acceleration voltage of, e.g., 180 kV, and a dose of 2.0 ⁇ 1014 (atoms/cm2).
  • the concentration is maximum in an area having a depth of 1 ⁇ m or less in the PBN base material surface, and the concentration gradually decreases as the depth increases.
  • the PBN support rod 12 in which Mg ions were implanted was subjected to annealing in a vacuum state at a temperature of about 900°C for an hour. It was confirmed that this annealing activated the Mg ions implanted in the PBN base material surface portion, the electrical resistance of the PBN base material surface decreases to a value of 109 ( ⁇ -cm2) by about 100 times, compared with the electrical resistance obtained before the annealing. This is because the crystallinity of the PBN base material is recovered by the annealing, and Mg is partially substituted for boron (B) to exhibit hole conduction. It was confirmed that the surface resistance rarely changed by a high-temperature operation in a vacuum state for a long time.
  • the maximum Mg concentration in the annealed PBN base material surface is lower than the original value indicated by the dotted line A, and the concentrations of the surface increase by about 10 times, as indicated by a solid line B in FIG. 2.
  • the Mg ions were diffused in a deeper area and widely distributed.
  • the surface electrical resistance of the PBN support rod having a surface in which Mg ions are implanted is decreased by annealing.
  • a change in surface resistance in a high-temperature operation for a long time can be prevented by the annealing, and a stable operation can be assured. In this manner, a slow-wave circuit support rod having the ion-implanted area M of a predetermined element extending in the dielectric base material surface to a predetermined depth can be obtained.
  • the dielectric support rod manufactured as described above was set in an electron microscope, electrons were kept irradiated on the dielectric support rod under conditions of acceleration voltages of 10 kV, 15 kV, and 20 kV for five minutes, the presence/absence of electrons charged on the surface of the dielectric support rod was quantatively examined. As a result, under any conditions, it was rarely detected that the dielectric support rod according to the present invention was charged.
  • an ion species to be implanted can be freely selected, and the ions can be implanted while counting the ions. For this reason, the number of ions can be set at high accuracy, and the electrical resistance of the surface can be accurately controlled.
  • the thermal, chemical, and mechanical resistances of the support rod of the present invention are good more than those of a conventional support rod having a surface on which a coating is plated or deposited. Since the present invention has an arrangement in which no resistive coating layer adheres to the surface of the dielectric support rod, the size of the dielectric support rod does not change, design and assembling can be performed at high accuracy.
  • Mg which is a Group II element is ion-implanted in the PBN base material
  • the element to be implanted is not limited to Mg.
  • At least one selected from other Group II elements (Be, Ca, Sr, Ba, Zn, Cd, Hg) may be ion-implanted at a proper dose in the BN base material serving as the dielectric support rod.
  • At least one selected from Group IV elements (Ti, Zr, Hf, C, Si, Ge, Sn, Pb) or Group VI elements (Cr, Mo, W, O, S, Se, Po) may be implanted at a proper dose.
  • Si as a Group IV element is ion-implanted in a dielectric support rod consisting of PBN.
  • a silicon fluoride (SiF4) gas is used as an ion species. The gas is ionized by discharging, and an Si element is implanted in a PBN base material.
  • a sample obtained by implanting Si ions in the surface of the PBN base material at a dose of 1 ⁇ 1014 (atoms/cm2) and a sample obtained by implanting Si ions at a dose of 2 ⁇ 1014 (atom/cm2), and a sample obtained by implanting Si ions at a dose of 5 ⁇ 1014 (atoms/cm2) were subjected to annealing in a vacuum state at about 900°C for about an hour.
  • the surface potentials of these samples obtained as described above were measured with an electron microscope. As a result, when the beam acceleration voltage of the electron microscope was set to be 10 kV, the surface potentials of the samples became 6.6 kV, 8.0 kV, and 9.7 kV, respectively. It was confirmed that an amount of charge is in inverse proportion to the number of implanted Si ions. Note that, in this measuring method, the charge amount becomes zero when the surface potential is equal to the acceleration voltage, i.e., 10 kV.
  • an element which causes the surface of the support rod after the annealing to have electrical conductivity at a predetermined high resistance can be arbitrarily selected in accordance with the relationship between the base material of the dielectric support rod and the element.
  • a metal element which easily obtains physical and chemical stability is preferably used.
  • the base material of the dielectric support rod is a Group III-IV compound such as boron nitride (BN)
  • at least one element selected from Group II, IV, or VI elements is preferably used as an ion species to be implanted.
  • the dielectric support rod in which ions are implanted is subjected to annealing in a non-oxidizing atmosphere, and an element constituting the base material is partially substituted for the implanted element to electrically, stably activate the implanted element.
  • the electrical resistance of the surface of the BN support rod is preferably decreased and stabilized.
  • the number of ions to be implanted preferably falls within the range of 1.0 ⁇ 1012 (atoms/cm2) to 1.0 ⁇ 1016 (atoms/cm2).
  • annealing performed after ion implantation may be performed in not only a vacuum state, but also a nitrogen atmosphere, inert gas (argon or the like) atmosphere, or another non-oxidizing atmosphere.
  • the temperature of the annealing is preferably set to be relatively high because the high temperature can stabilize a reaction within a short time. However, in practice, the temperature is preferably set to be a temperature falling within the range of 600°C to 1,200°C. When the annealing is performed at a temperature higher than the above temperature, the implanted element is abruptly evaporated and eliminated, and a required concentration cannot be obtained.
  • a high-frequency attenuator provided in a part of the BN dielectric support rod, for attenuating a high-frequency wave is also formed by ion implantation. More specifically, the concentration of a metal element implanted in the surface of the dielectric support rod 12 is set to be highest in a maximum attenuation area ATT in which a high-frequency wave propagating through a slow-wave line 13 is maximally attenuated, and the concentration gradually decreases at both the sides of the maximum attenuation area ATT, thereby obtaining a concentration distribution for a charge prevention effect as described above. Therefore, the surface resistance of the dielectric support rod has a distribution, as indicated by a lower curve R in FIG. 3B, such that the surface resistance is set to be a value at which a high-frequency wave is sufficiently absorbed in the maximum attenuation area ATT, and gradually increases in both the sides of the maximum attenuation area ATT.
  • the surface resistance of a high-frequency attenuation portion can be considerably accurately distributed by controlling the number of ions to be implanted.
  • peeling or a change in property rarely occurs.
  • the electrical discontinuity of the boundary between the high-frequency attenuation portion and other areas can be prevented. Since the high-frequency attenuation portion can also be formed in the step of implanting ions for preventing charging, the manufacturing process can be simplified.
  • a slow-wave line to which the present invention can be applied is not limited to a spiral slow-wave line.
  • a slow-wave line such as a double-ladder slow-wave line or a ring-and-bar-shaped slow-wave line which is supported by dielectric support rods can be used.
  • the surface of a dielectric support rod consisting of boron nitride can be prevented from being charged, and the dielectric support rod can be manufactured with good reproducibility and high accuracy. Peeling and a change in property rarely occurs, and a stable operation of a traveling-wave tube for a long period of time can be assured.

Landscapes

  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Microwave Tubes (AREA)
EP19950112960 1994-08-17 1995-08-17 Verfahren zum Herstellen einer, eine Verzögerungsleitung enthaltenden Schaltungsanordnung für eine Wanderfeldröhre Expired - Lifetime EP0702388B1 (de)

Applications Claiming Priority (6)

Application Number Priority Date Filing Date Title
JP19296294 1994-08-17
JP19296294 1994-08-17
JP192962/94 1994-08-17
JP12997795A JPH08111182A (ja) 1994-08-17 1995-05-29 進行波管の遅波回路構体及びその製造方法
JP129977/94 1995-05-29
JP12997794 1995-05-29

Publications (2)

Publication Number Publication Date
EP0702388A1 true EP0702388A1 (de) 1996-03-20
EP0702388B1 EP0702388B1 (de) 2002-02-27

Family

ID=26465215

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19950112960 Expired - Lifetime EP0702388B1 (de) 1994-08-17 1995-08-17 Verfahren zum Herstellen einer, eine Verzögerungsleitung enthaltenden Schaltungsanordnung für eine Wanderfeldröhre

Country Status (3)

Country Link
EP (1) EP0702388B1 (de)
JP (1) JPH08111182A (de)
DE (1) DE69525582T2 (de)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2003081628A1 (en) * 2002-03-21 2003-10-02 Sun-Shin Jung An unsymmetrical-dielectric loaded helical structure with negative dispersion characteristics and a wideband travelling-wave tube using the same
FR2883409A1 (fr) * 2005-03-18 2006-09-22 Thales Sa Procede de fabrication d'un top avec effet de charge reduit
CN103474312A (zh) * 2013-09-09 2013-12-25 电子科技大学 一种行波管夹持杆及其制备方法

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3235753A1 (de) 1982-09-27 1984-03-29 Siemens AG, 1000 Berlin und 8000 München Wanderfeldroehre mit einer wendelartigen verzoegerungsleitung
FR2646732A1 (fr) * 1989-05-04 1990-11-09 Raytheon Co Amplificateur a haute frequence possedant une structure a ondes lentes
JPH0359929A (ja) * 1989-07-28 1991-03-14 Toshiba Corp マイクロ波減衰器及びその製造方法
US5071055A (en) 1984-12-18 1991-12-10 Thomson Csf Travelling wave tube with a helix-tube delay line attached to a sleeve through the use of boron nitride dielectric supports
JPH0589788A (ja) 1991-09-27 1993-04-09 Nec Corp 進行波管用誘電体支柱

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3235753A1 (de) 1982-09-27 1984-03-29 Siemens AG, 1000 Berlin und 8000 München Wanderfeldroehre mit einer wendelartigen verzoegerungsleitung
US5071055A (en) 1984-12-18 1991-12-10 Thomson Csf Travelling wave tube with a helix-tube delay line attached to a sleeve through the use of boron nitride dielectric supports
FR2646732A1 (fr) * 1989-05-04 1990-11-09 Raytheon Co Amplificateur a haute frequence possedant une structure a ondes lentes
US5038076A (en) 1989-05-04 1991-08-06 Raytheon Company Slow wave delay line structure having support rods coated by a dielectric material to prevent rod charging
JPH0359929A (ja) * 1989-07-28 1991-03-14 Toshiba Corp マイクロ波減衰器及びその製造方法
JPH0589788A (ja) 1991-09-27 1993-04-09 Nec Corp 進行波管用誘電体支柱

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 015, no. 209 (E - 1072) 28 May 1991 (1991-05-28) *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2003081628A1 (en) * 2002-03-21 2003-10-02 Sun-Shin Jung An unsymmetrical-dielectric loaded helical structure with negative dispersion characteristics and a wideband travelling-wave tube using the same
FR2883409A1 (fr) * 2005-03-18 2006-09-22 Thales Sa Procede de fabrication d'un top avec effet de charge reduit
CN103474312A (zh) * 2013-09-09 2013-12-25 电子科技大学 一种行波管夹持杆及其制备方法
CN103474312B (zh) * 2013-09-09 2016-08-10 电子科技大学 一种行波管夹持杆及其制备方法

Also Published As

Publication number Publication date
DE69525582T2 (de) 2002-10-10
DE69525582D1 (de) 2002-04-04
JPH08111182A (ja) 1996-04-30
EP0702388B1 (de) 2002-02-27

Similar Documents

Publication Publication Date Title
US5656820A (en) Ion generation device, ion irradiation device, and method of manufacturing a semiconductor device
US6134300A (en) Miniature x-ray source
US8052884B2 (en) Method of fabricating microchannel plate devices with multiple emissive layers
US20040174956A1 (en) Apparatus and method for shaping high voltage potentials on an insulator
WO2009148643A2 (en) Microchannel plate devices with multiple emissive layers
JPH06243822A (ja) 多層多重極
US5038076A (en) Slow wave delay line structure having support rods coated by a dielectric material to prevent rod charging
US4361742A (en) Vacuum power interrupter
EP0702388B1 (de) Verfahren zum Herstellen einer, eine Verzögerungsleitung enthaltenden Schaltungsanordnung für eine Wanderfeldröhre
Gilmour Jr Microwave and millimeter-wave vacuum electron devices: inductive output tubes, klystrons, traveling-wave tubes, magnetrons, crossed-field amplifiers, and gyrotrons
EP1465232B1 (de) Leitendes Rohr als Reflektronlinse.
McCaughan et al. Low‐energy ion bombardment of silicon dioxide films on silicon
US3891884A (en) Electron discharge device having electron multipactor suppression coating on window body
JP2861968B2 (ja) 冷陰極を使用した電子銃およびマイクロ波管
Goebel et al. Gain stability of traveling wave tubes
Curren et al. Traveling-wave tube efficiency improvement with textured pyrolytic graphite multistage depressed collector electrodes
Zhang et al. S-band klystron with 300 MHz bandwidth at 850 kW peak power and 20 kW average power
US3474284A (en) High frequency tantalum attenuation in traveling wave tubes
US5619091A (en) Diamond films treated with alkali-halides
Pignatel et al. Electron and ion beam effects in Auger electron spectroscopy on insulating materials
JP3075752B2 (ja) 高周波導波管の気密窓
CA1221468A (en) Plasma cathode electron beam generating system
Mita An accelerated life test method for highly reliable on-board TWT's with a coated impregnated cathode
JPS63149901A (ja) マイクロ波装置
EP0276933A1 (de) Strahlungskollektor mit geringen elektrischen Verlusten

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 19950914

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE FR GB

17Q First examination report despatched

Effective date: 19960605

RIC1 Information provided on ipc code assigned before grant

Free format text: 7H 01J 23/24 A, 7H 01J 9/00 B

RTI1 Title (correction)

Free format text: METHOD OF MANUFACTURING A SLOW-WAVE CIRCUIT ASSEMBLY FOR TRAVELING-WAVE TUBE

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

REG Reference to a national code

Ref country code: GB

Ref legal event code: IF02

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE FR GB

REF Corresponds to:

Ref document number: 69525582

Country of ref document: DE

Date of ref document: 20020404

RIN2 Information on inventor provided after grant (corrected)

Free format text: GONPEI, KATSUHIRO, C/O INTELLECTUAL PROPERTY DIV. * HIRATA, HITOSHI, C/O INTELLECTUAL PROPERTY DIV. * FUJITA, KATUTOSHI, C/O INTELLECTUAL PROPERTY DIV.

ET Fr: translation filed
PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20020821

Year of fee payment: 8

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed

Effective date: 20021128

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20030808

Year of fee payment: 9

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20030813

Year of fee payment: 9

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20040302

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20040817

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20040817

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20050429

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST