CN104733267A - High ionization rate oxide cathode plasma source and preparation method thereof - Google Patents

High ionization rate oxide cathode plasma source and preparation method thereof Download PDF

Info

Publication number
CN104733267A
CN104733267A CN201510066212.4A CN201510066212A CN104733267A CN 104733267 A CN104733267 A CN 104733267A CN 201510066212 A CN201510066212 A CN 201510066212A CN 104733267 A CN104733267 A CN 104733267A
Authority
CN
China
Prior art keywords
plasma source
ionization rate
powder
high ionization
cathode plasma
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.)
Pending
Application number
CN201510066212.4A
Other languages
Chinese (zh)
Inventor
谢锦林
胡广海
金晓丽
袁林
张乔枫
杨尚川
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.)
University of Science and Technology of China USTC
Original Assignee
University of Science and Technology of China USTC
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 University of Science and Technology of China USTC filed Critical University of Science and Technology of China USTC
Priority to CN201510066212.4A priority Critical patent/CN104733267A/en
Publication of CN104733267A publication Critical patent/CN104733267A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J1/00—Details of electrodes, of magnetic control means, of screens, or of the mounting or spacing thereof, common to two or more basic types of discharge tubes or lamps
    • H01J1/02—Main electrodes
    • H01J1/13—Solid thermionic cathodes
    • H01J1/14—Solid thermionic cathodes characterised by the material
    • H01J1/142—Solid thermionic cathodes characterised by the material with alkaline-earth metal oxides, or such oxides used in conjunction with reducing agents, as an emissive material
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J9/00—Apparatus or processes specially adapted for the manufacture, installation, removal, maintenance of electric discharge tubes, discharge lamps, or parts thereof; Recovery of material from discharge tubes or lamps
    • H01J9/02—Manufacture of electrodes or electrode systems
    • H01J9/04—Manufacture of electrodes or electrode systems of thermionic cathodes

Abstract

The invention discloses a high ionization rate oxide cathode plasma source and a preparation method thereof. The high ionization rate oxide cathode plasma source comprises, by weight, one part of BaCO3, 0.6-0.8 part of SrCO3, 0.05-0.2 part of CaCO3 and 0.05-0.2 part of Sc2O3. The chemical purity of the BaCO3, the chemical purity of the SrCO3, the chemical purity of the CaCO3 and the chemical purity of the Sc2O3 are all 99.99%. The high ionization rate oxide cathode plasma source has the advantages that the emissive power of a cathode is improved while the ignition phenomenon is restrained.

Description

A kind of high ionization rate oxide coated cathode plasma source and preparation method thereof
Technical field
The present invention relates to a kind of high ionization rate oxide coated cathode plasma source and preparation method thereof.
Background technology
The LAPD device of UCLA university of the U.S. completes the design of large area oxide coated cathode the earliest, oxide coated cathode emissive material is alkaline earth oxide, but they in an atmosphere cannot stable existence, at high temperature must decompose generation by alkaline earth metal carbonate or hydroxide.Generally we use alkaline earth metal carbonate, and it is stable chemical nature in an atmosphere, and under vacuum conditions, pyrolysis produces oxide.Common alkaline earth oxide has CaO, SrO and BaO, and barytic work function is minimum, is good emissive material.BaO is by BaCO under high temperature 3decompose and produce, its reaction equation is as follows:
BaCO 3→BaO+CO 2
Under BaO high temperature, evaporation capacity is too large, and it can be combined with brium carbonate in thermal decomposition process, generates (BaOBaCO 3), this salt fusing point is low, fusing can generate hard close structure, be unfavorable for cathode activation and transmitting in decomposable process.Appropriate SrCO is added in carbonate 3, SrO than the more Zao generation of BaO and infusibility, can suppress the sintering of coating like this.CaCO 3coating can be made firmer, more resistance to Ions Bombardment, bond also more firm with negative electrode simultaneously.This is for extremely important as plasma source because Ions Bombardment sputtering can make coating thinning, emissivities decline and uneven.Also have a lot of people to think, SrO, CaO can adsorb more free barium, and can suppress the evaporation of free barium, form more launching centre.The reaction equation of the mixture of carbonate is:
Ba(Sr，Ca)CO 3→Ba(Sr，Ca)O+CO 2
This oxide coated cathode is relative to hot filament cathode, and its emission effciency has had significant lifting, but (normal operating discharge electric current is 0-10A/cm at big current launching condition 2) under easily sparking cause cathode impaired, the existence of sparking limits its emission effciency.
Why oxide coated cathode strikes sparks is because big current flows through coating and causes local overheating, and a large amount of free barium evaporation vaporizations, pile up ionization at cathode surface, then coating removes by a large amount of Ions Bombardment coating.If suppress sparking or reduce emission current, or increasing the conductivity of coating.The resistance of coating is divided into two parts, and one is powder coating resistance, and another part to form an intermediate layer between Base Metal and coating, and this part also has sizable resistance.The formation in intermediate layer is that reducing substances diffuses to based metal surfaces and barium monoxide generation reduction reaction because there is a large amount of reducing substanceses Base Metal inside, and reducing power the strongest be exactly elemental silicon, react as follows:
Si+2BaO→2Ba+SiO 2
2BaO+SiO 2→Ba 2SiO 4
The SiO that reaction generates 2(silicon dioxide) and Ba 2siO 4(BaOBaSiO 3) be the main component in intermediate layer, and they are non-conductive, at based metal surfaces skewness, certain local intermediate layer is thicker, resistance will be larger, may occur two kinds of results like this: one is that big current flows through intermediate layer and causes sparking, one is that intermediate layer forms compact texture for a long time and suppresses reduction reaction.The second situation generally there will not be, because this is a very very long process and requires that Base Metal silicone content is very high, and sparking is very possible.If inhibit the formation in intermediate layer, so from certain aspect, just inhibit sparking.
Summary of the invention
The invention provides a kind of high ionization rate oxide coated cathode plasma source and preparation method thereof, it can increase the emissivities of negative electrode while suppressing spark phenomenon to occur.
Technical problem to be solved by this invention realizes by the following technical solutions:
A kind of high ionization rate oxide coated cathode plasma source, it comprises the material of following parts by weight: brium carbonate BaCO 31 part, strontium carbonate SrCO 30.6-0.8 part, calcium carbonate CaCO 30.05-0.2 part, scandium oxide Sc 2o 30.05-0.2 part.
Described brium carbonate BaCO 3, strontium carbonate SrCO 3, calcium carbonate CaCO 3, scandium oxide Sc 2o 3chemical purity be all 99.99%.
The present invention also comprises a kind of preparation method of high ionization rate oxide coated cathode plasma source, and it comprises the steps:
A, by above-mentioned brium carbonate BaCO 3, strontium carbonate SrCO 3, calcium carbonate CaCO 3, scandium oxide Sc 2o 3proportional arrangement powder;
B, in the ratio of 1g powder 1 ~ 2ml acetic acid isoamyl fat to be added the powder that step a obtains, put into grinder and be ground to particle scale and be less than 3um, then add collodion in the ratio of 1g powder 1 ~ 2ml, after fully mixed, obtain suspension-turbid liquid for subsequent use;
C, use Al 2o 3sand paper clear base metallic plate, and the Base Metal plate of cleaning is fixed on electric turntable;
On the Base Metal plate that the suspension-turbid liquid even application that step b obtains by d obtains to step c;
E, volatilization naturally to be coated or baking are dry;
F, repetition steps d, e, until coating layer thickness reaches 40um-200um.
The invention has the beneficial effects as follows: the present invention adds the Sc of purity 99.99% in carbonate powder 2o 3(scandium oxide) powder increases the emissivities of negative electrode while just can suppressing to strike sparks.Non-conductive for intermediate layer medium reaction is generated Ba by scandium oxide 3sc 4o 9, this reaction condition is high temperature, and General Requirements is higher than 1000 DEG C.The scandium acid barium that reaction generates at high temperature (1000 DEG C ~ 1100 DEG C) has very strong emissivities (50A/cm 2), be the dominant emission material of immersion-type scandium acid negative electrode.Even if when oxide coated cathode working temperature is lower (about 900 DEG C), chemical reaction velocity is comparatively slow, but experiment proved response has still carried out, and significantly improves cathode emission ability and not sparking.
Embodiment
The technological means realized to make the present invention, creation characteristic, reaching object and effect is easy to understand, setting forth the present invention further below.
A kind of high ionization rate oxide coated cathode plasma source, it comprises the material of following parts by weight: brium carbonate BaCO 31 part, strontium carbonate SrCO 30.6-0.8 part, calcium carbonate CaCO 30.05-0.2 part, scandium oxide Sc 2o 30.05-0.2 part.
Brium carbonate BaCO 3, strontium carbonate SrCO 3, calcium carbonate CaCO 3, scandium oxide Sc 2o 3chemical purity be all 99.99%.
The present invention also comprises a kind of preparation method of high ionization rate oxide coated cathode plasma source, and it comprises the steps:
A, by above-mentioned brium carbonate BaCO 3, strontium carbonate SrCO 3, calcium carbonate CaCO 3, scandium oxide Sc 2o 3proportional arrangement powder;
B, in the ratio of 1g powder 1 ~ 2ml acetic acid isoamyl fat to be added the powder that step a obtains, put into grinder and be ground to particle scale and be less than 3um, then add collodion in the ratio of 1g powder 1 ~ 2ml, after fully mixed, obtain suspension-turbid liquid for subsequent use;
C, with 100 order Al 2o 3after sand papering Base Metal plate, then with nonwoven fabrics cleaning, after front surface is bright and clean, with 100 clean order Al 2o 3sand paper, at nickel plate surface paddle-tumble in the same direction, and is fixed on electric turntable by the Base Metal plate of cleaning;
The suspension-turbid liquid that step b obtains by d pours clean spray gun into, examination spray several times, after its tapered even vaporific knot, on the Base Metal plate that even application obtains to step c;
E, volatilization naturally to be coated or baking are dry;
F, repetition steps d, e, until coating layer thickness reaches 40um-200um, regulate spray time according to thickness.
The Sc of purity 99.99% is added in carbonate powder 2o 3(scandium oxide) powder increases the emissivities of negative electrode while just can suppressing to strike sparks, course of reaction is as follows:
20Ni+2Sc 2O 3→4ScNi 5+3O 2
9Ba 2SiO 4+16ScNi 5→4Ba 3Sc 4O 9+6Ba+9Si+80Ni
As can be seen from the above equation, non-conductive for intermediate layer medium reaction is generated Ba by scandium oxide 3sc 4o 9, this reaction condition is high temperature, and General Requirements is higher than 1000 DEG C.The scandium acid barium that reaction generates at high temperature (1000 DEG C ~ 1100 DEG C) has very strong emissivities (50A/cm 2), be the dominant emission material of immersion-type scandium acid negative electrode.Even if when oxide coated cathode working temperature is lower (about 900 DEG C), chemical reaction velocity is comparatively slow, but experiment proved response has still carried out, and significantly improves cathode emission ability and not sparking.
More than show and describe general principle of the present invention and principal character and advantage of the present invention.The technical staff of the industry should understand; the present invention is not restricted to the described embodiments; what describe in above-described embodiment and specification just illustrates principle of the present invention; without departing from the spirit and scope of the present invention; the present invention also has various changes and modifications, and these changes and improvements all fall in the claimed scope of the invention.Application claims protection range is defined by appending claims and equivalent thereof.

Claims (3)

1. a high ionization rate oxide coated cathode plasma source, it comprises the material of following parts by weight: brium carbonate BaCO 31 part, strontium carbonate SrCO 30.6-0.8 part, calcium carbonate CaCO 30.05-0.2 part, scandium oxide Sc 2o 30.05-0.2 part.
2. a kind of high ionization rate oxide coated cathode plasma source according to claim 1, is characterized in that: described brium carbonate BaCO 3, strontium carbonate SrCO 3, calcium carbonate CaCO 3, scandium oxide Sc 2o 3chemical purity be all 99.99%.
3. prepare a preparation method for a kind of high ionization rate oxide coated cathode plasma source described in any one of claim 1-2, it is characterized in that: it comprises the steps:
A, by above-mentioned brium carbonate BaCO 3, strontium carbonate SrCO 3, calcium carbonate CaCO 3, scandium oxide Sc 2o 3proportional arrangement powder;
B, in the ratio of 1g powder 1 ~ 2ml acetic acid isoamyl fat to be added the powder that step a obtains, put into grinder and be ground to particle scale and be less than 3um, then add collodion in the ratio of 1g powder 1 ~ 2ml, after fully mixed, obtain suspension-turbid liquid for subsequent use;
C, use Al 2o 3sand paper clear base metallic plate, and the Base Metal plate of cleaning is fixed on electric turntable;
On the Base Metal plate that the suspension-turbid liquid even application that step b obtains by d obtains to step c;
E, volatilization naturally to be coated or baking are dry;
F, repetition steps d, e, until coating layer thickness reaches 40um-200um.
CN201510066212.4A 2015-02-04 2015-02-04 High ionization rate oxide cathode plasma source and preparation method thereof Pending CN104733267A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201510066212.4A CN104733267A (en) 2015-02-04 2015-02-04 High ionization rate oxide cathode plasma source and preparation method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201510066212.4A CN104733267A (en) 2015-02-04 2015-02-04 High ionization rate oxide cathode plasma source and preparation method thereof

Publications (1)

Publication Number Publication Date
CN104733267A true CN104733267A (en) 2015-06-24

Family

ID=53457071

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201510066212.4A Pending CN104733267A (en) 2015-02-04 2015-02-04 High ionization rate oxide cathode plasma source and preparation method thereof

Country Status (1)

Country Link
CN (1) CN104733267A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105679624A (en) * 2016-03-03 2016-06-15 宁波凯耀电器制造有限公司 Bombardment-resistant electron emission material and preparation method thereof
CN108417470A (en) * 2018-03-19 2018-08-17 中国科学技术大学 A kind of high ionization rate large area oxide-coated cathode plasma source cathode and production method

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN86104753A (en) * 1985-07-19 1987-01-14 三菱电机株式会社 Cathod for electric valve
JPH03173035A (en) * 1989-11-09 1991-07-26 Samsung Electron Devices Co Ltd Dispenser cathode
CN1453809A (en) * 2002-04-25 2003-11-05 汤姆森许可贸易公司 Oxide cathode of high density thin emitting zone for eectronic gun
WO2005062334A1 (en) * 2003-12-23 2005-07-07 L.G. Philips Displays Netherlands B.V. Oxide cathode

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN86104753A (en) * 1985-07-19 1987-01-14 三菱电机株式会社 Cathod for electric valve
JPH03173035A (en) * 1989-11-09 1991-07-26 Samsung Electron Devices Co Ltd Dispenser cathode
CN1453809A (en) * 2002-04-25 2003-11-05 汤姆森许可贸易公司 Oxide cathode of high density thin emitting zone for eectronic gun
WO2005062334A1 (en) * 2003-12-23 2005-07-07 L.G. Philips Displays Netherlands B.V. Oxide cathode

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
姚宗熙等: ""用于CRT的氧化钪分散型阴极的试验研究"", 《真空科学与技术》 *
胡广海等: ""线性磁化装置氧化物阴极放电"", 《第十五届全国等离子体科学技术会议》 *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105679624A (en) * 2016-03-03 2016-06-15 宁波凯耀电器制造有限公司 Bombardment-resistant electron emission material and preparation method thereof
CN105679624B (en) * 2016-03-03 2017-08-25 宁波凯耀电器制造有限公司 A kind of electronic emission material of resistance to bombardment and preparation method thereof
CN108417470A (en) * 2018-03-19 2018-08-17 中国科学技术大学 A kind of high ionization rate large area oxide-coated cathode plasma source cathode and production method

Similar Documents

Publication Publication Date Title
EP1780749A2 (en) Plasma display panel and method for producing the same
JP5872998B2 (en) Alumina sintered body, member comprising the same, and semiconductor manufacturing apparatus
WO2011024821A1 (en) Electrode for discharge lamp, and process for production thereof
TW476974B (en) Getter, flat-panel display and method of production thereof
CN101383255A (en) Protecting layer, method for preparing the same and plasma display panel comprising the same
CN104733267A (en) High ionization rate oxide cathode plasma source and preparation method thereof
KR20110014713A (en) Emissive electrode materials for electric lamps and methods of making
CN105702542A (en) Rhenium doped tungsten-based alloy cathode and preparation method thereof
JPWO2011024924A1 (en) Discharge lamp electrode, discharge lamp electrode manufacturing method, and discharge lamp
US1552310A (en) Electrode for discharge tubes
US2476590A (en) Cathode coating
CN109935505B (en) Preparation method of low-temperature high-current-density scandium-containing oxide cathode
KR20020053857A (en) Cathode ray tube comprising a cathode of a composite material
Zhang et al. Influence of plasma spraying on the performance of oxide cathodes
JP2007056351A (en) Target for ion plating used for manufacturing of zinc oxide-based electroconductive film, its manufacturing method, and method for manufacturing zinc oxide-based electroconductive film
Wang et al. Progress on RE 2 O 3-Mo/W matrix secondary emitter materials
KR102123029B1 (en) Metal oxide-coated tungsten wires for highly efficient electron emitter and preparation method the same
JP3965298B2 (en) LIGHT EMITTING STRUCTURE, LIGHT EMITTING METHOD, AND LIGHTING BODY
US2579366A (en) Control circuit for multiple high resistance ignition electrode
US2533095A (en) Multiple gap arc starting ionizer
CN208478278U (en) A kind of high-power high-energy ignition gas discharging pipe
US20230202930A1 (en) Electron-emitting ceramic
Shang et al. Investigation on the conductivity-dependent performance in low voltage cathodoluminescence
JP2006193382A (en) Insulation structure, its production method, and field emission display device using the same
JP2007242624A (en) Luminescence structure, luminescence method, and lighting object

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
WD01 Invention patent application deemed withdrawn after publication

Application publication date: 20150624

WD01 Invention patent application deemed withdrawn after publication