JPH0136219B2 - - Google Patents
Info
- Publication number
- JPH0136219B2 JPH0136219B2 JP55004167A JP416780A JPH0136219B2 JP H0136219 B2 JPH0136219 B2 JP H0136219B2 JP 55004167 A JP55004167 A JP 55004167A JP 416780 A JP416780 A JP 416780A JP H0136219 B2 JPH0136219 B2 JP H0136219B2
- Authority
- JP
- Japan
- Prior art keywords
- cathode
- electron
- electron radioactive
- impregnated
- radioactive material
- 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
Links
- 239000012857 radioactive material Substances 0.000 claims description 15
- 239000000941 radioactive substance Substances 0.000 claims description 14
- 229910052751 metal Inorganic materials 0.000 claims description 13
- 239000002184 metal Substances 0.000 claims description 13
- 230000001681 protective effect Effects 0.000 claims description 9
- 238000004519 manufacturing process Methods 0.000 claims description 6
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 claims description 6
- 229910052721 tungsten Inorganic materials 0.000 claims description 6
- 239000010937 tungsten Substances 0.000 claims description 6
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 claims description 5
- 229910052750 molybdenum Inorganic materials 0.000 claims description 5
- 239000011733 molybdenum Substances 0.000 claims description 5
- 238000000034 method Methods 0.000 claims description 4
- 239000000843 powder Substances 0.000 claims description 4
- 238000005245 sintering Methods 0.000 claims description 3
- 239000011195 cermet Substances 0.000 claims description 2
- 239000000203 mixture Substances 0.000 claims description 2
- 239000010408 film Substances 0.000 description 8
- 239000000758 substrate Substances 0.000 description 7
- 150000002500 ions Chemical class 0.000 description 6
- 239000000126 substance Substances 0.000 description 4
- 230000008020 evaporation Effects 0.000 description 3
- 238000001704 evaporation Methods 0.000 description 3
- 238000005498 polishing Methods 0.000 description 3
- 238000004544 sputter deposition Methods 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- 238000000151 deposition Methods 0.000 description 2
- 238000010849 ion bombardment Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 238000007517 polishing process Methods 0.000 description 2
- ZNOKGRXACCSDPY-UHFFFAOYSA-N tungsten trioxide Chemical compound O=[W](=O)=O ZNOKGRXACCSDPY-UHFFFAOYSA-N 0.000 description 2
- 230000002159 abnormal effect Effects 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- 150000001768 cations Chemical class 0.000 description 1
- 238000005229 chemical vapour deposition Methods 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 229910003460 diamond Inorganic materials 0.000 description 1
- 239000010432 diamond Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000005470 impregnation Methods 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 125000004430 oxygen atom Chemical group O* 0.000 description 1
- 238000007747 plating Methods 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
- 239000011800 void material Substances 0.000 description 1
Classifications
-
- 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
Landscapes
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
Description
【発明の詳細な説明】
本発明は熱電子放射型陰極の製造方法に係り、
特に含浸型陰極、マツシユ陰極または電子放射性
物質と金属粉末を混合したものを陰極基体に焼結
するサーメツト型陰極で、動作時の電子逆衝撃や
イオン衝撃に対して電子放射性物質を有効に保護
するに適した熱電子放射型陰極の製造方法に関す
る。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a thermionic emission cathode,
In particular, impregnated cathodes, matte cathodes, or cermet cathodes in which a mixture of electron radioactive material and metal powder is sintered onto the cathode substrate effectively protect the electron radioactive material from electron back impact and ion bombardment during operation. The present invention relates to a method of manufacturing a thermionic emission type cathode suitable for
従来、例えばマグネトロンの陰極で電子逆衝撃
やイオン衝撃の強いマグネトロンまたは、長寿命
用のマグネトロンの陰極として、高融点多孔質金
属基体に電子放射性物質を含浸した含浸型陰極や
多孔質の金属基体にオキサイドと呼ばれる電子放
射性物質を有機溶剤に溶かして充填したマツシユ
陰極などが利用されている。これらの陰極は普通
のオキサイド陰極に比べて衝撃に耐え、長寿命の
効果を有しているが、高電圧のマグネトロンでは
これらの陰極をもつて電子逆衝撃やイオン衝撃の
エネルギーによる電子放射性物質の蒸発、飛散に
より、電子放射性物質が減つて寿命が短かくなる
のみならず、蒸発、飛散した電子放射性物質が陰
極以外の他の部分に付着して、アーキングやモー
ドジヤンプ等の原因となり、異常動作を起し好ま
しくない。 Conventionally, for example, as a magnetron cathode with strong electron back impact and ion impact, or as a long-life magnetron cathode, an impregnated cathode with a high melting point porous metal substrate impregnated with an electron radioactive substance or a porous metal substrate has been used. Matsushi cathodes, which are filled with an electron-emitting substance called oxide dissolved in an organic solvent, are used. These cathodes are more resistant to impact and have a longer lifespan than ordinary oxide cathodes, but in high-voltage magnetrons, these cathodes are used to prevent electrons from emitting radioactive materials due to the energy of electron reverse impact and ion impact. Evaporation and scattering not only reduce the amount of electron radioactive material and shorten its lifespan, but also cause the evaporated and scattered electron radioactive material to adhere to other parts other than the cathode, causing arcing and mode jumps, resulting in abnormal operation. This is undesirable because it causes
この原因を考察してみると、例えば含浸型陰極
ではタングステンやモリブデンの高融点金属粉末
を焼結させて陰極基体を構成しているが、粉末の
間〓がいわゆる電子放射性物質を含浸させる領域
で、この間〓は陰極の表面においても存在し、お
およそ直径３〜5μの穴となる。この穴の大きさ
は陰極全体から見れば非常に小さいが、電子やイ
オンの大きさと比較すると非常に大きく、この穴
部に存在する電子放射性物質はまともに電子やイ
オンによる衝撃を受けることになり、前述の如く
電子放射性物質の蒸発や飛散を起させることにな
る。 If we consider the cause of this, for example, in an impregnated cathode, the cathode base is constructed by sintering high-melting point metal powder such as tungsten or molybdenum, but the space between the powders is the area where the so-called electron radioactive substance is impregnated. , during this period, also exists on the surface of the cathode, forming holes with a diameter of approximately 3 to 5 μm. The size of this hole is very small when viewed from the whole cathode, but it is very large compared to the size of electrons and ions, and the electron radioactive material existing in this hole is directly bombarded by electrons and ions. As mentioned above, this causes evaporation and scattering of the electron radioactive material.
例えば含浸型陰極の製造方法で、陰極基体を形
成する際の研磨加工や電子放射性物質を含浸させ
た後の余剰の電子放射性物質を除去する研磨加工
において、陰極表面の粒子間空〓（穴）をつぶさ
ないように、応力の加わらないサンドペーパやダ
イヤモンドペースト等で研磨することが電子放射
特性に非常に効果のあることが特願昭53−74607
号（特公昭58−26769号公報）に開示されている。
前記の如く電子逆衝撃やイオン衝撃から電子放射
性物質を保護するためには、むしろ研磨時にこの
穴をつぶした方が良いように考えられがちであ
る。しかし電子放射性物質の含浸前にこの穴を機
械的につぶすと、電子放射性物質の含浸が完全に
できず、結果的に電子放射性物質の量が減るし、
また電子放射性物質の含浸後の研磨で穴をつぶし
ても、例えば穴の3/4がつぶれて1/4が電子放射性
物質の露出部分となり、電子放射性物質の露出部
分が全体の割合として減るだけで、露出部分は各
穴に連続的に存在しており、電子やイオンの衝撃
の保護には何ら役立たず、電子放射に寄与する面
積が減るだけで結果は良くない。 For example, in the manufacturing method of an impregnated cathode, in the polishing process when forming the cathode substrate or the polishing process to remove excess electron radioactive substance after impregnating it with an electron radioactive substance, interparticle spaces (holes) on the cathode surface are formed. Patent Application No. 1974-74607 shows that polishing with stress-free sandpaper, diamond paste, etc. to avoid crushing the material is very effective for improving electron emission characteristics.
No. (Special Publication No. 58-26769).
As mentioned above, in order to protect the electron radioactive material from electron back impact and ion impact, it is often thought that it is better to close up these holes during polishing. However, if this hole is mechanically crushed before impregnating with electron radioactive material, impregnation with electron radioactive material will not be completed, and as a result, the amount of electron radioactive material will decrease.
Furthermore, even if the hole is crushed by polishing after being impregnated with an electron radioactive substance, for example, 3/4 of the hole will be crushed and 1/4 will become an exposed part of the electron radioactive substance, and the exposed part of the electron radioactive substance will only decrease as a percentage of the total. In this case, the exposed part exists continuously in each hole, and does not provide any protection from electron or ion bombardment, but only reduces the area contributing to electron emission, which is not a good result.
本発明は上記ような欠点を解決するため、タン
グステンまたはモリブデンで形成した陰極基体に
電子放射性物質を含浸、充填、または焼結した後
の陰極の表面に、タングステンもしくはモリブデ
ンまたはこれらの酸化物をスパツタなどで付着す
ることにより、非常に細かい粒子で電子放射性物
質の表面を覆つて、動作時の電子やイオンの衝撃
から有効に保護される陰極の製造方法を提供する
ことにある。 In order to solve the above-mentioned drawbacks, the present invention has been made by sputtering tungsten or molybdenum or their oxides onto the surface of the cathode after impregnating, filling, or sintering a cathode base made of tungsten or molybdenum with an electron radioactive substance. It is an object of the present invention to provide a method for producing a cathode which is effectively protected from the impact of electrons and ions during operation by covering the surface of an electron-emitting substance with very fine particles.
第１図は本発明の一実施例である酸化タングス
テン（WO3）を陰極表面に付着させる装置の概
略図を示したもので、１は電子放射性物質を含浸
させた含浸型陰極で、陰極筒２と組み合せた状態
で治具３に挿入して陰極１が露出するように設置
し正の電極４に接続する。５は他方の負の電極で
ターゲツト６を保持しており、この実施例ではタ
ーゲツトを酸化タングステン（WO3）にしてい
る。７は例えばアルゴン（Ar）の不活性ガス雰
囲気で、８は高周波電圧を印加する電源である。
この装置により高周波の高電圧を印加するとAr
ガスは非常に高エネルギーをもつた陽イオンAr+
に電離し、これが電極の負側すなわちWO3面に
飛び込み、WO3がAr+の持つていた高エネルギー
を得て飛び出し、陰極１の表面に付着する。その
付着厚さは高電圧の印加時間にほぼ比例し、陰極
を使用するマグネトロン等の動作条件により調整
できるが、余り厚くなると電子放射特性に悪影響
するため3000Åから1μｍ以下に調整することが
望ましい。このWO3の性質は1400℃位で分解し
てタングステン（Ｗ）になるが、実際の陰極で
は、陰極に使用する材質、電子放射性物質等の影
響で1200℃以上に上げることができず、1200℃以
下では一部は分解してＷになるものもあるが
WO3の状態で存在するものもある。しかし一部
分解に伴うＯ原子の蒸発による空〓、更には真空
管にしてからの昇温による金属Ｗ自体または
WO3自体の収縮により保護膜内に空〓が生じ保
護膜全体に対する空〓の割合は、多孔質陰極基体
と同程度の20〜30％になる。そのためその間〓か
ら電子放射性物質は浸み出し、電子放射特性には
悪影響を及ぼさない。またWO3が一部残存する
ため抵抗率が増大するが保護膜の厚さが1μｍ以
下であれば実験的に電流特性に影響しない。 FIG. 1 shows a schematic diagram of an apparatus for depositing tungsten oxide (WO 3 ) on the cathode surface, which is an embodiment of the present invention. 1 is an impregnated cathode impregnated with an electron radioactive substance; 2 is inserted into a jig 3, installed so that the cathode 1 is exposed, and connected to the positive electrode 4. The other negative electrode 5 holds a target 6, and in this embodiment, the target is tungsten oxide (WO 3 ). 7 is an inert gas atmosphere such as argon (Ar), and 8 is a power source for applying a high frequency voltage.
When a high frequency high voltage is applied with this device, Ar
The gas is a cation Ar + with very high energy.
This ionizes and jumps into the negative side of the electrode, that is, the WO 3 surface, and the WO 3 gains the high energy of Ar + and jumps out, adhering to the surface of the cathode 1. The thickness of the deposit is approximately proportional to the high voltage application time and can be adjusted by the operating conditions of the magnetron using the cathode, but if it becomes too thick it will have a negative effect on the electron emission characteristics, so it is desirable to adjust it from 3000 Å to 1 μm or less. The property of WO 3 is that it decomposes into tungsten (W) at around 1400℃, but in actual cathodes, it is not possible to raise the temperature above 1200℃ due to the influence of the material used for the cathode, the electron radioactive substance, etc. At temperatures below ℃, some of it decomposes into W.
Some exist in the WO 3 state. However, due to the evaporation of O atoms due to partial decomposition, there is a void, and furthermore, the metal W itself is
Due to the shrinkage of WO 3 itself, voids are created in the protective film, and the percentage of voids in the entire protective film is 20 to 30%, which is about the same as that of the porous cathode substrate. Therefore, electron radioactive substances seep out from between them and do not adversely affect the electron emission characteristics. Further, resistivity increases because some WO 3 remains, but as long as the thickness of the protective film is 1 μm or less, it does not affect the current characteristics experimentally.
この保護膜として付着する物質は金属単体でも
良く、上記実施例のように酸化物でも良いが、金
属としては1200℃以下で蒸発せず、しかも陰極基
体に用いる金属と熱膨張係数がほぼ同じ金属を用
いれば、熱膨張係数の差による剥離等の心配も生
ぜず、真空管の動作中有効に電子放射性物質を保
護することができる。その結果この方法により製
造した陰極を50kWのマグネトロンに使用した場
合、従来は平均で1500時間の寿命であつたものが
2000時間に延びた。また上述のようにスパツタに
より保護膜を付着させるため、陰極の上面のみな
らず側面および陰極表面の凹凸部の影の部分（陰
極の表面はマクロ的にみると平らに形成されてい
るが、ミクロ的にみると非常に凹凸がある。）に
も有効に付着し、非常に効果がある。また付着さ
せる工程は電子放射性物質を含浸、充填もしくは
固着した後のいずれの工程の状態でも行なうこと
ができる。 The substance attached as this protective film may be a single metal or an oxide as in the above example, but as a metal, it is a metal that does not evaporate below 1200℃ and has a coefficient of thermal expansion that is almost the same as the metal used for the cathode substrate. If this is used, there will be no fear of peeling due to differences in thermal expansion coefficients, and the electron radioactive material can be effectively protected during operation of the vacuum tube. As a result, when a cathode manufactured using this method is used in a 50kW magnetron, the lifespan of the cathode, which previously had an average of 1500 hours, has increased.
It was extended to 2000 hours. In addition, since the protective film is attached by sputtering as described above, it is necessary to apply the protective film not only to the top surface of the cathode but also to the side surfaces and the shadows of the uneven parts of the cathode surface (the surface of the cathode is flat from a macro perspective, but microscopically). It adheres effectively even to surfaces (which are very uneven when viewed from the outside) and is very effective. Further, the step of adhering can be performed in any step after impregnating, filling, or fixing the electron radioactive substance.
尚、上記の保護膜の付着は、スパツタでなくて
もCVD法によつても同様にできることは言う迄
もない。しかも電子放射性物質を含浸、充填等し
た後の陰極表面への処理のためメツキ法による付
着は不可能であり、また薄い膜で均一に付着する
必要があるため塗布等では適しない。 It goes without saying that the above-mentioned protective film can be attached not only by sputtering but also by CVD method. Furthermore, since the cathode surface is treated after being impregnated or filled with an electron-emitting substance, it is impossible to attach the cathode by a plating method, and it is not suitable for coating or the like because it needs to be attached uniformly with a thin film.
以上説明したように、本発明によれば、陰極基
体の金属と熱膨張係数が同程度の金属又はその酸
化物を使用の目的に応じた厚さだけ付着する工程
を付加するだけで、マグネトロンのアーキングや
モードジヤンプを有効に防ぐことができ、しかも
マグネトロンの寿命も大幅に向上することができ
る利点を有する。 As explained above, according to the present invention, by simply adding a step of attaching a metal having a thermal expansion coefficient similar to that of the metal of the cathode substrate or its oxide to a thickness corresponding to the purpose of use, the magnetron can be It has the advantage that arcing and mode jump can be effectively prevented, and the life of the magnetron can be greatly improved.
第１図は本発明による保護膜を付着させる装置
の一例の概略断面図である。
１……電子放射性物質を含浸した陰極、４，５
……電極、６……ターゲツト、７……Ar雰囲気、
８……電源。
FIG. 1 is a schematic cross-sectional view of an example of an apparatus for depositing a protective film according to the present invention. 1...Cathode impregnated with electron radioactive material, 4,5
... Electrode, 6 ... Target, 7 ... Ar atmosphere,
8...Power supply.
Claims (1)
くは充填した含浸型陰極もしくはマツシユ陰極ま
たは電子放射性物質と金属粉末を混合したものを
焼結したサーメツト陰極の製造方法において、タ
ングステンまたはモリブデンで形成した陰極基体
に、電子放射性物質を含浸、充填または焼結した
後の陰極の各工程のいずれかの工程で、動作時の
電子放射性物質を保護する保護膜として、タング
ステンもしくはモリブデンまたはこれらの酸化物
を陰極表面に付着させる工程を付加したことを特
徴とする熱電子放射型陰極の製造方法。1. A cathode base made of tungsten or molybdenum in a method for producing an impregnated cathode or matte cathode in which a porous metal base is impregnated or filled with an electron radioactive substance, or a cermet cathode in which a mixture of an electron radioactive substance and metal powder is sintered. After impregnating, filling, or sintering the cathode with an electron radioactive material, tungsten or molybdenum or their oxides are added to the surface of the cathode as a protective film to protect the electron radioactive material during operation. 1. A method for manufacturing a thermionic emission cathode, characterized by adding a step of adhering it to.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP416780A JPS56102036A (en) | 1980-01-17 | 1980-01-17 | Manufacture of thermionic emission type cathode |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP416780A JPS56102036A (en) | 1980-01-17 | 1980-01-17 | Manufacture of thermionic emission type cathode |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS56102036A JPS56102036A (en) | 1981-08-15 |
| JPH0136219B2 true JPH0136219B2 (en) | 1989-07-28 |
Family
ID=11577174
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP416780A Granted JPS56102036A (en) | 1980-01-17 | 1980-01-17 | Manufacture of thermionic emission type cathode |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS56102036A (en) |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5679830A (en) * | 1979-11-09 | 1981-06-30 | Thomson Csf | Hottcathode* method of manufacturing same and electron tube using same cathode |
-
1980
- 1980-01-17 JP JP416780A patent/JPS56102036A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5679830A (en) * | 1979-11-09 | 1981-06-30 | Thomson Csf | Hottcathode* method of manufacturing same and electron tube using same cathode |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS56102036A (en) | 1981-08-15 |
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