JPH04325459A - Dielectric ceramics and production thereof - Google Patents
Dielectric ceramics and production thereofInfo
- Publication number
- JPH04325459A JPH04325459A JP3097744A JP9774491A JPH04325459A JP H04325459 A JPH04325459 A JP H04325459A JP 3097744 A JP3097744 A JP 3097744A JP 9774491 A JP9774491 A JP 9774491A JP H04325459 A JPH04325459 A JP H04325459A
- Authority
- JP
- Japan
- Prior art keywords
- tio2
- mgo
- titanate
- mixed
- excess
- 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
Links
- 239000000919 ceramic Substances 0.000 title claims abstract description 25
- 238000004519 manufacturing process Methods 0.000 title claims description 4
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 claims abstract description 44
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 claims abstract description 7
- 229910052749 magnesium Inorganic materials 0.000 claims abstract description 7
- 239000011777 magnesium Substances 0.000 claims abstract description 7
- 239000000203 mixture Substances 0.000 claims abstract description 7
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims abstract description 5
- 239000000843 powder Substances 0.000 claims abstract description 5
- 239000013078 crystal Substances 0.000 claims abstract description 4
- 238000002156 mixing Methods 0.000 claims abstract description 4
- AOWKSNWVBZGMTJ-UHFFFAOYSA-N calcium titanate Chemical compound [Ca+2].[O-][Ti]([O-])=O AOWKSNWVBZGMTJ-UHFFFAOYSA-N 0.000 claims abstract 4
- 238000010304 firing Methods 0.000 claims abstract 2
- 229910003080 TiO4 Inorganic materials 0.000 claims description 6
- 239000002253 acid Substances 0.000 abstract description 10
- 238000007747 plating Methods 0.000 abstract description 9
- 238000010306 acid treatment Methods 0.000 abstract description 4
- 239000011230 binding agent Substances 0.000 abstract description 3
- 238000000465 moulding Methods 0.000 abstract description 3
- 239000011347 resin Substances 0.000 abstract description 2
- 229920005989 resin Polymers 0.000 abstract description 2
- 239000011163 secondary particle Substances 0.000 abstract description 2
- 239000007858 starting material Substances 0.000 abstract 2
- 239000000463 material Substances 0.000 description 8
- 230000000052 comparative effect Effects 0.000 description 6
- 239000002994 raw material Substances 0.000 description 6
- 238000002441 X-ray diffraction Methods 0.000 description 5
- 239000010408 film Substances 0.000 description 5
- 238000012360 testing method Methods 0.000 description 4
- 238000002474 experimental method Methods 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 229910010413 TiO 2 Inorganic materials 0.000 description 1
- 238000001354 calcination Methods 0.000 description 1
- 238000012790 confirmation Methods 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000010298 pulverizing process Methods 0.000 description 1
- 238000001694 spray drying Methods 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 description 1
Abstract
Description
【０００１】0001
【産業上の利用分野】本発明は、チタン酸マグネシウム
−チタン酸カルシウム系誘電体セラミックスの製造方法
に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing magnesium titanate-calcium titanate dielectric ceramics.
【０００２】0002
【従来の技術】近年、誘電体セラミックスをマイクロ波
に応用したものとして、ディレイライン、フィルター回
路、マイクロ波回路、誘電体フィルター等のマイクロ波
回路（ＭＩＣ）に用いられる基板や、導波回路、導波線
路、アンテナの媒体用セラミック等があげられる。[Prior Art] In recent years, dielectric ceramics have been applied to microwaves, such as substrates used in microwave circuits (MIC) such as delay lines, filter circuits, microwave circuits, dielectric filters, waveguide circuits, etc. Examples include waveguide lines, ceramics for antenna media, etc.
【０００３】その中で、回路形成時の膜付けは、Ａｇ−
Ｐｄ、Ｃｕでの厚膜や薄膜の手法がとられていた。しか
し、Ａｇペーストでは高周波数域での損失が大きく、通
常１ＧＨｚが限界であることや、小型化の傾向から、誘
電損失の小さいＣｕの膜付けが主流になりつつある。Among these, Ag-
Thick film and thin film methods using Pd and Cu have been used. However, Ag paste has a large loss in a high frequency range, and the limit is usually 1 GHz, and due to the trend toward miniaturization, the use of a Cu film with low dielectric loss is becoming mainstream.
【０００４】また、従来よりチタン酸マグネシウム（以
下ＭＴという）−チタン酸カルシウム（以下ＣＴという
）系誘電体セラミックスが広く用いられてきた。この誘
電体セラミックスを製造するには、ＭｇＯ／ＴｉＯ２
のモル比が１であるＭＴと、ＣａＯ／ＴｉＯ２ のモル
比が１であるＣＴとを混合し、噴霧乾燥後、仮焼し、さ
らに所定の粒度になるように微粉砕した後、バインダー
を加えて噴霧乾燥し、得られた原料を所定の形状にプレ
ス成形して、焼成するようになっていた。さらに、上記
ＭＴとＣＴとの混合比を変えることで、誘電率εｒ の
値を調整することができた。また、このようなＭＴ−Ｃ
Ｔ系の誘電体セラミックスにおいては、Ｃｕの厚膜を形
成する際に還元雰囲気で処理をすると、抵抗値が急激に
低下するなどの問題があることから、Ｃｕメッキによる
膜付けが検討されている。Furthermore, magnesium titanate (hereinafter referred to as MT)-calcium titanate (hereinafter referred to as CT) dielectric ceramics have been widely used. To produce this dielectric ceramic, MgO/TiO2
MT in which the molar ratio of CaO/TiO2 is 1 is mixed with CT in which the molar ratio of CaO/TiO2 is 1. After spray drying, calcining, and further pulverizing to a predetermined particle size, a binder is added. The resulting raw material was then press-molded into a predetermined shape and fired. Furthermore, by changing the mixing ratio of MT and CT, the value of the dielectric constant εr could be adjusted. Also, such MT-C
For T-based dielectric ceramics, there are problems such as a sudden drop in resistance when processing in a reducing atmosphere when forming a thick Cu film, so film deposition by Cu plating is being considered. .
【０００５】[0005]
【発明が解決しようとする課題】ところが、ＭＴ−ＣＴ
系誘電体セラミックスにＣｕメッキを施す場合、表面を
酸処理する工程でセラミックスが浸食されててしまい、
メッキしたＣｕが内部まで浸透して、絶縁抵抗値を低下
させてしまうという問題点があった。[Problem to be solved by the invention] However, MT-CT
When applying Cu plating to dielectric ceramics, the ceramics are eroded during the process of acid treatment of the surface.
There was a problem in that the plated Cu penetrated into the interior and lowered the insulation resistance value.
【０００６】[0006]
【課題を解決するための手段】そこで、本発明は、ＭＴ
−ＣＴ系誘電体セラミックスにおいてＭｇ２ ＴｉＯ４
の結晶構造を含まないようにしたことを特徴とする。[Means for Solving the Problems] Therefore, the present invention provides MT
-Mg2 TiO4 in CT-based dielectric ceramics
It is characterized by not containing any crystal structure.
【０００７】即ち、本発明者等が種々実験の結果、従来
のＭＴ−ＣＴ系誘電体セラミックスにはＭｇ２ ＴｉＯ
４ が存在しており、このＭｇ２ ＴｉＯ４ が特に耐
酸性が悪いため、上記Ｃｕメッキ時の酸処理工程で腐食
しやすいことを見出したのである。したがって、Ｍｇ２
ＴｉＯ４ を含まないＭＴ−ＣＴ系誘電体セラミック
スとすることで、耐酸性を高め、Ｃｕメッキを好適に行
うことができる。なお、本発明において、Ｍｇ２ Ｔｉ
Ｏ４ を含まないとは、セラミックス表面をＸ線回折に
よって分析したときに、Ｍｇ２ ＴｉＯ４ のピークが
検出されないことを意味する。That is, as a result of various experiments conducted by the present inventors, conventional MT-CT dielectric ceramics contain Mg2TiO.
They found that this Mg2TiO4 has particularly poor acid resistance and is easily corroded in the acid treatment step during the Cu plating. Therefore, Mg2
By using MT-CT dielectric ceramics that do not contain TiO4, acid resistance can be improved and Cu plating can be suitably performed. In addition, in the present invention, Mg2Ti
Not containing O4 means that no Mg2TiO4 peak is detected when the ceramic surface is analyzed by X-ray diffraction.
【０００８】また、このようにＭｇ２ ＴｉＯ４ の存
在しないＭＴ−ＣＴ系誘電体セラミックスを製造するた
めには、あらかじめ原料中において、ＭｇＯに対するＴ
ｉＯ２ のモル量を過剰としておけばよい。具体的には
、ＣＴと、ＭｇＯ／ＴｉＯ２ のモル比が１より小さい
ＭＴとを混合し、この原料を用いて成形、焼成すればよ
い。あるいは、ＣＴと、ＭｇＯ／ＴｉＯ２ のモル比が
１以上のＭＴとを混合した後、さらにＴｉＯ２ を添加
してＴｉＯ２ 量を過剰とし、この原料を用いて成形、
焼成することもできる。[0008] Furthermore, in order to produce MT-CT dielectric ceramics in which Mg2TiO4 is not present, T
The molar amount of iO2 may be in excess. Specifically, CT and MT having a MgO/TiO2 molar ratio of less than 1 may be mixed, and this raw material may be used to mold and fire. Alternatively, after mixing CT and MT having a MgO/TiO2 molar ratio of 1 or more, TiO2 is further added to make the amount of TiO2 excessive, and this raw material is used for molding.
It can also be baked.
【０００９】[0009]
【実施例】以下本発明の実施例を説明する。[Examples] Examples of the present invention will be described below.
【００１０】ＭＴ−ＣＴ系誘電体セラミックスにおいて
、ＭＴ、ＣＴの組成比と誘電率εｒ との関係を調べた
ところ、図１のような結果であった。また、誘電率εｒ
の温度係数τｆ が０ｐｐｍ／℃となる組成はεｒ
＝２１付近にあることが実験により得られた。そこで、
以下εｒ ＝２１、２４、２７となる組成のものについ
て実験を行った。When we investigated the relationship between the composition ratio of MT and CT and the dielectric constant εr in MT-CT dielectric ceramics, we found the results shown in FIG. Also, the dielectric constant εr
The composition for which the temperature coefficient τf of is 0 ppm/℃ is εr
It was experimentally found that the value is around 21. Therefore,
Experiments were conducted on the following compositions with εr =21, 24, and 27.
【００１１】実験例１
ＭＴ材として、表１に示すようにＭｇＯ／ＴｉＯ２ の
モル比が異なる３種類の原料を用意した。また、ＣＴ材
としてＣａＯ／ＴｉＯ２ のモル比が１．００のものを
用意した。Experimental Example 1 Three types of raw materials having different MgO/TiO2 molar ratios as shown in Table 1 were prepared as MT materials. In addition, a CT material with a CaO/TiO2 molar ratio of 1.00 was prepared.
【００１２】0012
【表１】[Table 1]
【００１３】これら３種類のＭＴ材と１種類のＣＴ材を
用いて、それぞれ、誘電率εｒ ＝２１、２４、２７と
なるような組成比とした。これらの原料粉末を樹脂ミル
中に入れ、ジルコニアボールで混合した後、噴霧乾燥し
、さらに所定の粒度になるように微粉砕した後、バイン
ダーを加えて噴霧乾燥し、得られた２次粒子を成形圧力
１ｔｏｎ／ｃｍ２ でプレス成形し、焼成して、直径１
０ｍｍで１ｃｍ３ の大きさのテストピース、直径２０
ｍｍで厚み５ｍｍのテストピース、および２×２インチ
で厚み０．６ｍｍのテストピースを得た。これらのテス
トピースを用いて、Ｘ線回折によるＭｇ２ ＴｉＯ４
の存在の確認、誘電率εｒ の測定、耐酸性評価、Ｃｕ
メッキ後の抵抗値低下の有無を調べた。結果は表２に示
す通りである。Using these three types of MT materials and one type of CT material, the composition ratios were set such that the dielectric constant εr=21, 24, and 27, respectively. These raw material powders are placed in a resin mill, mixed with zirconia balls, spray-dried, finely pulverized to a predetermined particle size, then a binder is added and spray-dried, and the resulting secondary particles are Press molded at a molding pressure of 1 ton/cm2 and fired to a diameter of 1
0mm and 1cm3 size test piece, diameter 20
A test piece measuring 2 mm and 5 mm thick and a test piece measuring 2×2 inches and 0.6 mm thick were obtained. Using these test pieces, Mg2TiO4 by X-ray diffraction
Confirmation of existence of Cu, measurement of dielectric constant εr, evaluation of acid resistance, Cu
The presence or absence of a decrease in resistance value after plating was investigated. The results are shown in Table 2.
【００１４】表２中の、Ｎｏ．１、４、７に示したもの
は、ＭｇＯ／ＴｉＯ２ のモル比が１以上の材料（ＭＴ
−Ａ）を用いた比較例である。これらの比較例は、いず
れもＭｇ２ ＴｉＯ４ が存在し、耐酸性が０．３〜０
．５ｍｇ／ｃｍ・１０ｍｉｎと悪く、Ｃｕメッキ後の抵
抗値低下があった。[0014] In Table 2, No. 1, 4, and 7 are materials with a MgO/TiO2 molar ratio of 1 or more (MT
This is a comparative example using -A). In all of these comparative examples, Mg2TiO4 is present and the acid resistance is 0.3 to 0.
．． It was poor at 5 mg/cm for 10 min, and the resistance value decreased after Cu plating.
【００１５】これに対し、Ｎｏ．２、３、５、６、８、
９に示したものは、ＭｇＯ／ＴｉＯ２ のモル比が１よ
り小さい材料（ＭＴ−Ｂ、ＭＴ−Ｃ）を用いた本発明実
施例である。これらの実施例は、いずれもＭｇ２ Ｔｉ
Ｏ４ が存在せず、耐酸性が０．０１ｍｇ／ｃｍ・１０
ｍｉｎ以下と優れており、Ｃｕメッキ後の抵抗値低下が
なかった。したがって、Ｍｇ２ ＴｉＯ４ の存在をな
くすことで、耐酸性を向上できることがわかる。On the other hand, No. 2, 3, 5, 6, 8,
9 is an example of the present invention using materials (MT-B, MT-C) in which the MgO/TiO2 molar ratio is less than 1. In both of these examples, Mg2Ti
No O4, acid resistance 0.01mg/cm・10
It was excellent, being less than min, and there was no decrease in resistance value after Cu plating. Therefore, it can be seen that the acid resistance can be improved by eliminating the presence of Mg2TiO4.
【００１６】なお、比較例であるＮｏ．１と、本発明実
施例であるＮｏ．３について、Ｘ線回折を行ったときの
チャート図をそれぞれ図２、図３に示すように、比較例
では明確にＭｇ２ ＴｉＯ４ のピークが検出されるの
に対し、本発明実施例ではＭｇ２ ＴｉＯ４ のピーク
が全く検出されなかった。[0016] As a comparative example, No. 1 and No. 1, which is an embodiment of the present invention. As shown in FIG. 2 and FIG. 3, respectively, the chart diagrams obtained when X-ray diffraction was performed for No. 3, the peak of Mg2 TiO4 was clearly detected in the comparative example, whereas the peak of Mg2 TiO4 was clearly detected in the example of the present invention. No peaks were detected.
【００１７】[0017]
【表２】[Table 2]
【００１８】実験例２
次に、上記表２中の比較例であるＮｏ．１に対し、Ｔｉ
Ｏ２ を添加して、同様の実験を行った。結果は表３に
示すように、ＴｉＯ２ を添加することによって、耐酸
性を向上できることがわかる。これは、もともとＴｉＯ
２ 量の少なかったＭＴ材（ＭＴ−Ａ）に対し、ＴｉＯ
２ を添加することによって、結果的にＭｇＯに対する
ＴｉＯ２ のモル量を過剰にできたためであると考えら
れる。Experimental Example 2 Next, No. 2, which is a comparative example in Table 2 above, was tested. 1, Ti
A similar experiment was performed with the addition of O2. As shown in Table 3, the results show that acid resistance can be improved by adding TiO2. This was originally TiO
2 Compared to the MT material (MT-A), which had a small amount, TiO
This is thought to be because the addition of TiO2 resulted in an excess molar amount of TiO2 relative to MgO.
【００１９】[0019]
【表３】[Table 3]
【００２０】[0020]
【発明の効果】このように、本発明によれば、ＭＴ−Ｃ
Ｔ系誘電体セラミックスにおいて、Ｍｇ２ ＴｉＯ４
の結晶構造を含まないようにしたことによって、耐酸性
を優れたものとできる。そのため、Ｃｕメッキ時に酸処
理を行っても腐食せず、良好にＣｕ膜付けができる。[Effects of the Invention] As described above, according to the present invention, MT-C
In T-based dielectric ceramics, Mg2 TiO4
By not including the crystal structure, it is possible to achieve excellent acid resistance. Therefore, even if acid treatment is performed during Cu plating, corrosion does not occur, and a Cu film can be satisfactorily attached.
【００２１】また、このようなＭＴ−ＣＴ系誘電体セラ
ミックスを製造するには、ＭｇＯに対するＴｉＯ２ の
モル量が過剰となるように、ＭＴとＣＴとを混合し、こ
の原料を用いて成形、焼成すればよく、高品質の誘電体
セラミックスを容易に得ることができる。[0021] In addition, in order to manufacture such MT-CT dielectric ceramics, MT and CT are mixed so that the molar amount of TiO2 is in excess of MgO, and this raw material is molded and fired. High quality dielectric ceramics can be easily obtained.
【図１】ＭＴ−ＣＴ系誘電体セラミックスにおける組成
比と誘電率εｒ との関係を示すグラフである。FIG. 1 is a graph showing the relationship between composition ratio and dielectric constant εr in MT-CT dielectric ceramics.
【図２】比較例のＭＴ−ＣＴ系誘電体セラミックスにお
ける、Ｘ線回折チャート図である。FIG. 2 is an X-ray diffraction chart of an MT-CT dielectric ceramic of a comparative example.
【図３】本発明実施例のＭＴ−ＣＴ系誘電体セラミック
スにおける、Ｘ線回折チャート図である。FIG. 3 is an X-ray diffraction chart of the MT-CT dielectric ceramic according to the example of the present invention.
Claims (2)
、チタン酸マグネシウム−チタン酸カルシウム系の組成
からなることを特徴とする誘電体セラミックス。1. A dielectric ceramic characterized by having a magnesium titanate-calcium titanate composition that does not contain a Mg2 TiO4 crystal structure.
となるように、チタン酸マグネシウムとチタン酸カルシ
ウムの粉末を混合し、成形、焼成する工程からなる誘電
体セラミックスの製造方法。2. A method for producing dielectric ceramics, which comprises the steps of mixing powders of magnesium titanate and calcium titanate so that the molar amount of TiO2 is in excess of MgO, and then forming and firing the powder.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3097744A JP3034073B2 (en) | 1991-04-26 | 1991-04-26 | Dielectric ceramic having plated layer and method of manufacturing the same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3097744A JP3034073B2 (en) | 1991-04-26 | 1991-04-26 | Dielectric ceramic having plated layer and method of manufacturing the same |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04325459A true JPH04325459A (en) | 1992-11-13 |
| JP3034073B2 JP3034073B2 (en) | 2000-04-17 |
Family
ID=14200399
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3097744A Expired - Lifetime JP3034073B2 (en) | 1991-04-26 | 1991-04-26 | Dielectric ceramic having plated layer and method of manufacturing the same |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3034073B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004168579A (en) * | 2002-11-19 | 2004-06-17 | Tdk Corp | Dielectric porcelain composition and dielectric resonator |
-
1991
- 1991-04-26 JP JP3097744A patent/JP3034073B2/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004168579A (en) * | 2002-11-19 | 2004-06-17 | Tdk Corp | Dielectric porcelain composition and dielectric resonator |
| JP4569857B2 (en) * | 2002-11-19 | 2010-10-27 | Ｔｄｋ株式会社 | Dielectric ceramic composition and dielectric resonator |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3034073B2 (en) | 2000-04-17 |
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