JPS59203343A - Impregnated cathode - Google Patents
Impregnated cathodeInfo
- Publication number
- JPS59203343A JPS59203343A JP58077432A JP7743283A JPS59203343A JP S59203343 A JPS59203343 A JP S59203343A JP 58077432 A JP58077432 A JP 58077432A JP 7743283 A JP7743283 A JP 7743283A JP S59203343 A JPS59203343 A JP S59203343A
- Authority
- JP
- Japan
- Prior art keywords
- cathode
- impregnated cathode
- powder
- fine
- impregnated
- 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
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
- H01J1/20—Cathodes heated indirectly by an electric current; Cathodes heated by electron or ion bombardment
- H01J1/28—Dispenser-type cathodes, e.g. L-cathode
Landscapes
- Solid Thermionic Cathode (AREA)
Abstract
Description
【発明の詳細な説明】
〔発明の利用分野〕
本発明はブラウン管、撮像管等の陰極材料に係り、特に
高い電子放出が得られる高性能の含浸形陰極に関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to cathode materials for cathode ray tubes, image pickup tubes, etc., and particularly to a high-performance impregnated cathode that can provide high electron emission.
通常の含浸形陰極の飽和電流密度は１ｏｏｏｒで３〜４
Ａ／。２である。これに対して、ＳＣ酸化物を添加した
含浸形陰極の飽和電流密度は８００ＣでＩＯＡ／ｃｎ２
の値が得られる。しかし、ＳＣ酸化物添加の含浸形陰極
は空間電荷制限領域において、引き出し電圧に対する放
出電流値が低いため（Ａ、 Ｖａｎ Ｏｏｓｔｒｏｍ、
Ａｐｐｌ、 ５ｕｒｆ、Ｓｃｉ、 ２．１９７９゜１
７３）、低温下で使用するのに難があわ、実用化まで至
っていない。The saturation current density of a normal impregnated cathode is 3 to 4 at 1ooor.
A/. It is 2. On the other hand, the saturation current density of the impregnated cathode containing SC oxide is IOA/cn2 at 800C.
The value of is obtained. However, the impregnated cathode with SC oxide has a low emission current value with respect to the extraction voltage in the space charge limited region (A, Van Oostrom,
Appl, 5urf, Sci, 2.1979°1
73), it is difficult to use at low temperatures and has not been put into practical use.
本発明の目的はＳＣ酸化物添加の含浸形陰極の低温領域
における放出電流特性を改善することにある。An object of the present invention is to improve the emission current characteristics of an impregnated cathode containing SC oxide in a low temperature region.
ＳＣ酸化物添加の含浸形陰極は動作温度において、表面
に不均一なＳＣ酸化物の析出物を形成するため、表面準
位が不均一となり、低電界領域では電子放出しにくい欠
点があった。本発明はＳＣ酸化物添加の含浸形陰極の表
面上に、微細なＷ粉、スカンジウム酸化物、および電子
放出物質の均一層を設けて、表面準位を均一にし、高い
電子放出を可能にしたところに特徴がある。The impregnated cathode containing SC oxide has the drawback that non-uniform SC oxide precipitates are formed on the surface at operating temperatures, resulting in non-uniform surface states and difficulty in emitting electrons in a low electric field region. The present invention provides a uniform layer of fine W powder, scandium oxide, and electron-emitting material on the surface of an impregnated cathode containing SC oxide, making the surface level uniform and enabling high electron emission. The place has its characteristics.
上記微細なＷ粉、スカンジウム酸化物、電子放出物質の
均一層の作製方法は種々考えられるが、例えば陰極表面
上に微細なＷ粉あるいは多結晶体のＷ膜を設け、熱処理
法で微細なＷ粉、スカンジウム酸化物、電子放出物質の
均一層を作製することができる。Various methods can be considered for producing the above-mentioned uniform layer of fine W powder, scandium oxide, and electron-emitting material. A uniform layer of powder, scandium oxide, and electron-emitting material can be created.
以下、本発明の実施例を詳細に説明する。 Examples of the present invention will be described in detail below.
実施例１
第１図は従来の５Ｃ２０３含有の含浸形陰極の断面図を
示す。１はＷ粒、２は８ Ｃ２０ｉ１粒、３は電子放出
物質である。Ｗ粒は粒径が５〜１１０Ａ１である。Example 1 FIG. 1 shows a cross-sectional view of a conventional impregnated cathode containing 5C203. 1 is a W grain, 2 is one 8 C20i grain, and 3 is an electron emitting material. The W grains have a grain size of 5 to 110A1.
通常の含浸法、（Ｈ２気流中、１７００ＣＸ２分加熱）
で予じめ作製したｗ−ｓｃ２ｏ３の多孔質体の中に含浸
させた。この５Ｃ２０３添加の含浸形陰極の飽和電流特
性を測定して、従来の含浸形陰極およびＯｓ被覆の含浸
形陰極と比較した結果を第２図に示す。Normal impregnation method (heated at 1700CX for 2 minutes in H2 stream)
It was impregnated into a porous body of w-sc2o3 prepared in advance. The saturation current characteristics of this 5C203-added impregnated cathode were measured and compared with a conventional impregnated cathode and an Os-coated impregnated cathode, and the results are shown in FIG.
４は通常の含浸形陰極の特性、５はＯｓ被覆の含浸形陰
極の特性、６は５Ｃ２０３添加の含浸形陰極の特性であ
る。含浸形陰極に５Ｃ２０３を添加すると飽和電流密度
が著しく向上する。しかし、５Ｃ２０３添加の含浸形陰
極は低電圧の引き出し電圧下では放出電流が低い欠点が
ある。第３図はアノードにＭＯ板を用い、カソードとア
ノード間距離を１叫に設定し、８００Ｃの温度において
カソードから放出される電流を引き出し電圧の平方根で
プロットした結果である。７は８Ｃｘ０３添加の含浸形
陰極の特性を示し低い引き出し電圧下では放出電流が低
いのが分る。これは含浸形陰極の表面部構造が第１図に
示したように、５ｃ２ｏｓや壁孔の偏析などの表面上に
微細なＷ粉層を設けた場合の結果である。Ｗ粉層は下地
のＷ基体の粒径５〜１０μｍよシ小さい０．１〜１μｍ
の微細なものから成り、その厚さは０．５μｍ〜２μｍ
とした。このＷ粉密着の５ＣｚＯａ添加の含浸形陰極は
低い引き出し電圧下でも放出電流が高いのが分る。これ
はｓｃ、ｏ３添加の含浸形陰極の表面上に微細なＷ粉層
を設けた場合、高温の動作温度で下地のＳ Ｃ２０，成
分と電子放出物質が微細なＷ粉層の空孔部に浸透して、
表面に均一なＷ粒、５Ｃ２０３、電子放出物質の層を形
成しただめと考えられる。この構造の模式図を第４図に
示す。９は５Ｃ２０３添加の含浸形陰極、１０は表面上
に密着している微細なＷ粉、５Ｃ２０３、電子放出物質
からなる層である。Ｗ粉の粒径が０．１μｍ１１以下で
あると、高温で焼結時にＷ粉の局部的な粒成長を逆に生
じてしまうため、放出電流と電圧の関係が第３図の７の
特性に低下してしまった。4 is a characteristic of a normal impregnated cathode, 5 is a characteristic of an Os-coated impregnated cathode, and 6 is a characteristic of an impregnated cathode added with 5C203. Adding 5C203 to the impregnated cathode significantly improves the saturation current density. However, the 5C203-added impregnated cathode has the drawback of low emission current under low extraction voltage. FIG. 3 shows the results of plotting the current emitted from the cathode at a temperature of 800 C using the square root of the extraction voltage, using an MO plate as the anode and setting the distance between the cathode and the anode to 1. No. 7 shows the characteristics of an 8Cx03-added impregnated cathode, and it can be seen that the emission current is low under a low extraction voltage. This is the result when the surface structure of the impregnated cathode is such that a fine W powder layer is provided on the surface of 5c2os or wall hole segregation, as shown in FIG. The W powder layer has a particle size of 0.1 to 1 μm, which is smaller than the particle size of the underlying W substrate, which is 5 to 10 μm.
It consists of fine particles, and its thickness is 0.5 μm to 2 μm.
And so. It can be seen that this 5CzOa-added impregnated cathode in close contact with W powder has a high emission current even under a low extraction voltage. This is because when a fine W powder layer is provided on the surface of an impregnated cathode with SC, O3 added, the underlying SC20, components and electron-emitting substances are absorbed into the pores of the fine W powder layer at high operating temperatures. Penetrate,
This is thought to be due to the formation of a uniform layer of W grains, 5C203, and electron emitting material on the surface. A schematic diagram of this structure is shown in FIG. Reference numeral 9 is an impregnated cathode containing 5C203, and 10 is a layer consisting of fine W powder, 5C203, and an electron-emitting substance that is in close contact with the surface. If the particle size of the W powder is less than 0.1 μm11, local grain growth of the W powder will occur during sintering at high temperatures, and the relationship between the emission current and voltage will change to the characteristic 7 in Figure 3. It has declined.
父、〜や粒の粒径が２μｍ以上では下地の含浸形陰極の
〜・〜ｆ基体の一次粒径と近くなシすぎて、Ｗ粒の均一
分散が雄〃−シくなり、この場合も望ましい結果が得ら
れなかった。If the grain size of the W grains is 2 μm or more, it will be too close to the primary grain size of the underlying impregnated cathode, making it difficult to uniformly disperse the W grains. The desired results were not achieved.
実施例２
実施例１に記した微細なＷ粉の替υ、Ｗ膜の被覆層を設
けることを行った。Ｗ膜は通常のスパッター法で作製し
、膜厚を０．１〜５μｍとした。このＷ膜の被覆しであ
る５Ｃ２０３添加の含浸形陰極の特性を測定したところ
、飽和電流密度では第２図の６の特性、放出電流−電圧
の関係では第３図の８の特性が得られた。これはスパッ
ター法で作製したＷ膜は０．０５〜０，２μｍの多結晶
体であるため、熱処理を施すと、下地の含浸形陰極から
、５ｃ２０３と電子放出物質が拡散してきて、第４図に
示したような均一性の良い表面構造を形成したためであ
る。したがって、Ｗ膜被覆の５Ｃ２０３添加の含浸形陰
極も低い引き出し電圧下で高い電子放出をすることが理
解される。膜厚が０．１μｍ以下ではＷ膜の被覆が不十
分で、５μｍ以上では特性を安定化させるエージング時
間が長くなシすぎ、いずれの場合も望ましい結果を得る
ことができなかった。Example 2 The fine W powder described in Example 1 was replaced with a W film coating layer. The W film was produced by a normal sputtering method and had a film thickness of 0.1 to 5 μm. When we measured the characteristics of the 5C203-added impregnated cathode coated with this W film, we found that the saturation current density had the characteristic 6 in Figure 2, and the emission current-voltage relationship had the characteristic 8 in Figure 3. Ta. This is because the W film produced by the sputtering method is a polycrystalline material with a size of 0.05 to 0.2 μm, so when it is heat-treated, 5c203 and the electron-emitting substance diffuse from the underlying impregnated cathode, as shown in Figure 4. This is because a surface structure with good uniformity as shown in Figure 3 was formed. Therefore, it is understood that the 5C203-added impregnated cathode coated with a W film also emits high electrons under a low extraction voltage. When the film thickness is less than 0.1 μm, the W film coverage is insufficient, and when it is more than 5 μm, the aging time required to stabilize the characteristics is too long, and in either case, desired results could not be obtained.
〔発明の効果〕
本発明によればＳＣ添加の含浸形陰極の低電圧領域にお
ける電子放出を高めることができ、ブラウン管や撮像管
等の陰極材料の高電流密度化に寄与することができる。[Effects of the Invention] According to the present invention, electron emission in the low voltage region of an impregnated cathode added with SC can be enhanced, and it can contribute to increasing the current density of cathode materials such as cathode ray tubes and image pickup tubes.
第１図は５Ｃ２０３添加の含浸形陰極の縦断面図、第２
図は従来法で作製した含浸形陰極と５Ｃ２０３添加含浸
形陰極の飽和電流特性図、第３図は従来の５Ｃ２０３添
加含浸形陰極と本発明の陰極における放出電流と引き出
し電圧の関係図、第４図は本発明の含υ形陰極の縦断面
図である。
１・・・タングステン粒、２・・・酸化スカンジウム粒
、３・・・電子放出物質、４・・・従来の含浸形陰極の
飽和電流特性、５・・・オスミウム被覆含浸形陰極の飽
和電流特性、６・・・５Ｃ２０３添加含浸形陰極の飽和
電流重性、７・・・５Ｃ２０３添加含浸形陰極の放出電
流と電圧の関係、８・・・本発明の含浸形陰極の放出電
流と電圧の関係、９・・・５Ｃ２０３添加含浸形陰極の
拡大断閉 （図
鎖 ２ 図
第 ３ 図
、１−
７ｏ心ｊ２［Figure 1 is a longitudinal cross-sectional view of an impregnated cathode with 5C203 added.
The figure is a saturation current characteristic diagram of an impregnated cathode made by a conventional method and a 5C203-added impregnated cathode, Fig. 3 is a relationship between emission current and extraction voltage for a conventional 5C203-added impregnated cathode and the cathode of the present invention, and Fig. 4 The figure is a longitudinal cross-sectional view of the υ-shaped cathode of the present invention. 1... Tungsten grains, 2... Scandium oxide particles, 3... Electron-emitting material, 4... Saturation current characteristics of conventional impregnated cathode, 5... Saturation current characteristics of osmium-coated impregnated cathode , 6...5 Saturation current gravity of C203-added impregnated cathode, 7...5 Relationship between emission current and voltage of C203-added impregnated cathode, 8... Relationship between emission current and voltage of impregnated cathode of the present invention , 9...5 Expansion and disconnection of C203-added impregnated cathode (Fig. 2, Fig. 3, 1-7o core j2 [
Claims (1)
酸化物及びバリウム酸化物の電子放出物質とから成る含
浸形陰極において、陰極表面上に微細なＷ粉、スカンジ
ウム酸化物、電子放出物質からなる均一層を設けること
を特徴とする含浸形陰極。 ２、−ヒ記微細なＷ粉として、０．１μｍから２μｍの
範囲の粒径のものを用いる特許請求の範囲第１項記載の
含浸形陰極。[Claims] 1. In an impregnated cathode consisting of a porous W substrate and scandium oxide and barium oxide electron-emitting substances filled in the pores, fine W powder and scandium powder are formed on the surface of the cathode. An impregnated cathode characterized by providing a uniform layer of an oxide and an electron-emitting substance. 2.-The impregnated cathode according to claim 1, wherein the fine W powder has a particle size in the range of 0.1 μm to 2 μm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58077432A JPS59203343A (en) | 1983-05-04 | 1983-05-04 | Impregnated cathode |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58077432A JPS59203343A (en) | 1983-05-04 | 1983-05-04 | Impregnated cathode |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS59203343A true JPS59203343A (en) | 1984-11-17 |
Family
ID=13633839
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP58077432A Pending JPS59203343A (en) | 1983-05-04 | 1983-05-04 | Impregnated cathode |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS59203343A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0248417A2 (en) * | 1986-06-06 | 1987-12-09 | Kabushiki Kaisha Toshiba | Impregnated cathode |
| US4873052A (en) * | 1984-10-05 | 1989-10-10 | U.S. Philips Corporaton | Method of manufacturing a scandate dispenser cathode and scandate dispenser cathode manufactured according to the method |
| EP0651419A1 (en) * | 1993-10-28 | 1995-05-03 | Koninklijke Philips Electronics N.V. | Dispenser cathode and method of manufacturing a dispenser cathode |
| BE1007677A3 (en) * | 1993-10-28 | 1995-09-12 | Philips Electronics Nv | Method for manufacturing a dispenser cathode |
| EP0831512A1 (en) * | 1995-06-09 | 1998-03-25 | Kabushiki Kaisha Toshiba | Impregnated cathode structure, cathode substrate used for the structure, electron gun structure using the cathode structure, and electron tube |
-
1983
- 1983-05-04 JP JP58077432A patent/JPS59203343A/en active Pending
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4873052A (en) * | 1984-10-05 | 1989-10-10 | U.S. Philips Corporaton | Method of manufacturing a scandate dispenser cathode and scandate dispenser cathode manufactured according to the method |
| EP0248417A2 (en) * | 1986-06-06 | 1987-12-09 | Kabushiki Kaisha Toshiba | Impregnated cathode |
| EP0651419A1 (en) * | 1993-10-28 | 1995-05-03 | Koninklijke Philips Electronics N.V. | Dispenser cathode and method of manufacturing a dispenser cathode |
| BE1007677A3 (en) * | 1993-10-28 | 1995-09-12 | Philips Electronics Nv | Method for manufacturing a dispenser cathode |
| EP0831512A1 (en) * | 1995-06-09 | 1998-03-25 | Kabushiki Kaisha Toshiba | Impregnated cathode structure, cathode substrate used for the structure, electron gun structure using the cathode structure, and electron tube |
| EP0831512A4 (en) * | 1995-06-09 | 1999-02-10 | Toshiba Kk | Impregnated cathode structure, cathode substrate used for the structure, electron gun structure using the cathode structure, and electron tube |
| US6034469A (en) * | 1995-06-09 | 2000-03-07 | Kabushiki Kaisha Toshiba | Impregnated type cathode assembly, cathode substrate for use in the assembly, electron gun using the assembly, and electron tube using the cathode assembly |
| US6304024B1 (en) | 1995-06-09 | 2001-10-16 | Kabushiki Kaisha Toshiba | Impregnated-type cathode substrate with large particle diameter low porosity region and small particle diameter high porosity region |
| US6447355B1 (en) | 1995-06-09 | 2002-09-10 | Kabushiki Kaisha Toshiba | Impregnated-type cathode substrate with large particle diameter low porosity region and small particle diameter high porosity region |
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