JP2000169225A - Piezoelectric parts and their production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a piezoelectric part that has excellent resistance to heat and humidity and can reduce the deviation of resonance frequency due to the temperature cycle by substituting a part of lead titanate zirconate with other components, then adding Mn3O4 to the resultant main component of a specific chemical composition, and providing a counter electrode on the surface of the piezoelectric porcelain plate. SOLUTION: Mn3O4, as a sub-component, is added to the main components in an amount of 0.3-0.8 pt.wt., based on 100 pts.wt. of the main components that comprises PbO, TiO2, ZrO2, La2O3, Bi2O3, WO3, and Mn3O4 and is represented by the formula (0.02<=α<=-0.08; 0.01<=β<=0.05; 0.002<=r<=0.01; 9.01<=<=0.05; 0.50<=B<=0.74; 0.25<=C<=0.48; A+B+C=1). Then, resultant mixture is molded and fired to give a sintered product. The direct electric field of 2.5-3.5 KV/mm is loaded to the sintered product at 130-180 deg.C for polarization. The sintered product is cut vertically to the polarization direction so that the resonance frequency may become the desired number. The resonance electrode 2 is formed on both of the cut faces of the sintered product whereby the objective piezoelectric part is obtained.

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【０００１】[0001]

【発明の属する技術分野】本発明は、特に厚みすべりモ
ード共振を利用したフィルタ、発振子等の圧電部品およ
びその製造方法に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piezoelectric component such as a filter and an oscillator using thickness-shear mode resonance, and a method of manufacturing the same.

【０００２】[0002]

【従来の技術】従来、圧電部品に用いる圧電磁器組成物
としてはチタン酸ジルコン酸鉛磁器、マグネシウムニオ
ブ酸チタン酸ジルコン酸鉛磁器および亜鉛ニオブ酸チタ
ン酸ジルコン酸鉛磁器などがあり、使用目的に応じて種
々の改良がなされてきた。2. Description of the Related Art Conventionally, piezoelectric ceramic compositions used for piezoelectric components include lead zirconate titanate porcelain, lead zirconate porcelain magnesium niobate and lead zirconate zinc niobate porcelain. Various improvements have been made accordingly.

【０００３】[0003]

【発明が解決しようとする課題】フィルタ、発振子等の
圧電部品は、半田付け実装温度に耐えうる耐熱性（脱分
極が少ない）と耐熱後の共振周波数変化が小さいことお
よび電子機器の過酷な環境下での使用を前提とした信頼
性（特に耐湿性）が要求されている。Piezoelectric components such as filters and oscillators have heat resistance (less depolarization) that can withstand the soldering mounting temperature, small changes in resonance frequency after heat resistance, and severe conditions in electronic equipment. There is a demand for reliability (especially moisture resistance) assuming use in an environment.

【０００４】しかしながら従来の圧電部品は実用上に重
要な信頼性の一つである温度サイクル前後で共振周波数
が変化するという問題を有していた。However, the conventional piezoelectric component has a problem that the resonance frequency changes before and after a temperature cycle, which is one of the reliability which is important in practical use.

【０００５】そこで本発明は、温度サイクルによる共振
周波数変化の少ない圧電部品を提供することを目的とす
るものである。SUMMARY OF THE INVENTION It is an object of the present invention to provide a piezoelectric component in which a change in resonance frequency due to a temperature cycle is small.

【０００６】[0006]

【課題を解決するための手段】この目的を達成するため
に本発明の圧電部品は、圧電磁器板と、この圧電磁器板
の表面に設けた対向電極とを備え、前記圧電磁器板は一
般式（化２）で表される主成分１００重量％に対して、
副成分としてＭｎ₃Ｏ₄を０．３〜０．８重量％添加して
形成したものである。In order to achieve this object, a piezoelectric component according to the present invention comprises a piezoelectric ceramic plate and a counter electrode provided on the surface of the piezoelectric ceramic plate, wherein the piezoelectric ceramic plate is of a general type. With respect to 100% by weight of the main component represented by the chemical formula 2,
The Mn ₃ O ₄ as a sub-component are those formed by adding 0.3 to 0.8 wt%.

【０００７】[0007]

【化２】 Embedded image

【０００８】この構成によると、本発明の圧電部品はＰ
ＺＴの一部を適当量のＰｂ（Ｍｎ_{1/ 2}Ｗ_1/2）Ｏ₃で置換
し、さらにＰｂの適当量をＢｉで置換するとともにＭｎ
₃Ｏ₄の添加で半田耐熱後の共振周波数の変化を低減する
ことができる。また、Ｐｂの適当量をＬａで置換するこ
とにより温度サイクルによる共振周波数変化を低減でき
る。According to this structure, the piezoelectric component of the present invention has a P
Mn with partially substituted ZT an appropriate amount of _{Pb (Mn 1/2 W 1/2} ) O 3, further substituting an appropriate amount of Pb in Bi
_By adding ₃ O ₄ , a change in resonance frequency after heat resistance of the solder can be reduced. Further, by replacing an appropriate amount of Pb with La, it is possible to reduce a change in resonance frequency due to a temperature cycle.

【０００９】[0009]

【発明の実施の形態】本発明の請求項１に記載の発明
は、圧電磁器板と、この圧電磁器板の表面に設けた対向
電極とを備え、前記圧電磁器板は、一般式（化３）で表
される主成分１００重量％に対して、副成分としてＭｎ
₃Ｏ₄を０．３〜０．８重量％添加して形成した圧電部品
であり、耐熱性、耐湿性に優れ、熱衝撃印加後の共振周
波数変化が小さく、温度サイクルによる共振周波数変化
の少ないものである。DETAILED DESCRIPTION OF THE INVENTION The invention according to claim 1 of the present invention comprises a piezoelectric ceramic plate and a counter electrode provided on the surface of the piezoelectric ceramic plate, wherein the piezoelectric ceramic plate has a general formula (Chemical Formula 3). ), 100% by weight of the main component
Piezoelectric component formed by adding 0.3 to 0.8% by weight of ₃ O ₄ , excellent in heat resistance and moisture resistance, little change in resonance frequency after applying thermal shock, and little change in resonance frequency due to temperature cycle Things.

【００１０】請求項２に記載の発明は、一般式（化３）
で表される主成分１００重量％に対して、副成分として
Ｍｎ₃Ｏ₄を０．３〜０．８重量％添加して成形体を得る
第１の工程と、次にこの成形体を焼成して焼結体を得る
第２の工程と、次いでこの焼結体を１３０〜１８０℃の
温度範囲において２．５〜３．５ｋＶ／ｍｍの範囲内の
直流電界を印加して分極する第３の工程と、次に所望の
共振周波数となるように前記焼結体を分極方向に対して
垂直に切断する第４の工程と、その後前記焼結体の切断
面に対向電極を形成する第５の工程を備えた圧電部品の
製造方法であり、耐熱性、耐湿性に優れ、熱衝撃印加後
の共振周波数変化が少なく、温度サイクルによる共振周
波数変化の少ない圧電部品を得ることができる。The invention according to claim 2 is a compound of the general formula (3)
A first step of adding 0.3 to 0.8% by weight of Mn ₃ O ₄ as an auxiliary component to 100% by weight of the main component represented by A second step of obtaining a sintered body by applying a DC electric field in the range of 2.5 to 3.5 kV / mm in a temperature range of 130 to 180 ° C. A fourth step of cutting the sintered body perpendicularly to the polarization direction so as to have a desired resonance frequency, and a fifth step of forming a counter electrode on the cut surface of the sintered body. This is a method for producing a piezoelectric component having the steps of (1) to (3), and it is possible to obtain a piezoelectric component having excellent heat resistance and moisture resistance, having a small change in resonance frequency after application of a thermal shock, and having a small change in resonance frequency due to a temperature cycle.

【００１１】以下本発明の実施の形態について厚みすべ
りモード共振子を例に図面を参照しながら説明する。Hereinafter, embodiments of the present invention will be described with reference to the drawings, taking a thickness-shear mode resonator as an example.

【００１２】図１は本実施の形態における厚みすべりモ
ード共振器の斜視図であり、圧電磁器板１の上，下両面
に共振用の対向電極２を形成したものである。まず原料
としてＰｂＯ，ＴｉＯ₂，ＺｒＯ₂，Ｌａ₂Ｏ₃，Ｂｉ
₂Ｏ₃，ＷＯ₃，Ｎｂ₂Ｏ₅，Ｍｎ₃Ｏ ₄を（表１）の組成と
なるように正確に秤量し、ボールミルによりよく混合し
た。FIG. 1 shows a thickness sliding mode according to the present embodiment.
FIG. 3 is a perspective view of a piezoelectric resonator, showing both upper and lower piezoelectric ceramic plates 1.
And a counter electrode 2 for resonance. First raw materials
As PbO, TiO_Two, ZrO_Two, La_TwoO_Three, Bi
_TwoO_Three, WO_Three, Nb_TwoO_Five, Mn_ThreeO _FourWith the composition of (Table 1)
Weigh accurately and mix well with a ball mill.
Was.

【００１３】[0013]

【表１】 [Table 1]

【００１４】なお、原料はこれらのみに限られるもので
なく化学反応により上記の酸化物を生成するものであれ
ば他の化合物を使用しても良い。次に前記混合物を９０
０℃の温度で仮焼し、さらにボールミルにより粉砕し
た。これを乾燥した後結合剤としてのポリビニールアル
コール水溶液に加え、造粒した後１ｔｏｎ／ｃｍ²の圧
力で加圧成形し、縦５０ｍｍ、横４５ｍｍ、高さ７ｍｍ
の成形体を得た。ここで得られた成形体を閉炉中で１０
５０〜１２７０℃の温度で１時間焼成し、得られた圧電
磁器矩形板より厚みすべりモード共振子を以下のように
して作製した。The raw materials are not limited to these, and other compounds may be used as long as they produce the above-mentioned oxide by a chemical reaction. The mixture is then
The mixture was calcined at a temperature of 0 ° C. and further pulverized by a ball mill. This was dried, then added to a polyvinyl alcohol aqueous solution as a binder, granulated, and then molded under pressure at a pressure of 1 ton / cm ² , 50 mm long, 45 mm wide, and 7 mm high.
Was obtained. The molded body obtained here was placed in a closed furnace for 10 minutes.
It was fired at a temperature of 50 to 1270 ° C. for 1 hour, and a thickness-shear mode resonator was manufactured from the obtained piezoelectric ceramic rectangular plate as follows.

【００１５】まず圧電磁器矩形板を研磨して厚み５ｍｍ
の圧電磁器板１とした後、両面に銀電極を焼き付け、１
２５〜１８５℃のシリコンオイル中で２．４〜３．６０
ｋＶ／ｍｍの直流電界を３０分間印加して分極処理し
た。次に厚みが０．５ｍｍ厚みになるように切断し、下
層が厚み０．０５μｍのＣｒ層、上層が厚み１μｍのＡ
ｕ層の二層蒸着膜よりなる対向電極２を対向する両切断
面に形成し、さらに分極方向に切断することにより図１
に示した矩形板状厚みすべりモード共振子を得た。First, a piezoelectric ceramic rectangular plate is polished to a thickness of 5 mm.
After baking silver electrodes on both sides,
2.4 to 3.60 in silicone oil at 25 to 185 ° C.
Polarization treatment was performed by applying a DC electric field of kV / mm for 30 minutes. Next, it is cut to a thickness of 0.5 mm, and the lower layer is a 0.05 μm thick Cr layer, and the upper layer is a 1 μm thick A layer.
A counter electrode 2 made of a two-layer vapor-deposited film of a u-layer is formed on both cut surfaces facing each other, and further cut in the polarization direction.
A rectangular plate-shaped thickness shear mode resonator shown in FIG.

【００１６】このようにして作製した厚みすべりモード
共振子につき密度ρ、比誘電率ε₁₁ ^T/ε₀、電気機械結
合係数ｋ₁₅を測定した。耐熱性は厚みすべりモード共振
子を２８０℃のホットプレート上で１分間保持した後の
電気機械結合係数ｋ₁₅および共振周波数の変化率を測定
した。ｋ₁₅≧０．３、｜ｋ₁₅変化率｜≦５％、｜共振周
波数変化率｜≦０．２％のものを耐熱性良好と判定し
た。The thickness-slip mode thus produced
Density ρ, relative permittivity ε per resonator₁₁ ^{T /}ε₀, Electromechanical tying
Coefficient k₁₅Was measured. Heat resistance is thickness-shear mode resonance
After the child was kept on a hot plate at 280 ° C. for 1 minute.
Electromechanical coupling coefficient k₁₅And rate of change of resonance frequency
did. k₁₅≧ 0.3, | k₁₅Rate of change | ≤ 5% | Resonance circumference
It is judged that the heat resistance is good when the wave number change rate | ≦ 0.2%
Was.

【００１７】以下上記耐熱試験を半田耐熱試験と記載す
る。測定結果の内で本発明の範囲内の分極（１５０℃，
３．０ｋＶ／ｍｍ，３０分）を施したものを圧電磁器焼
成温度（密度最大）とともに（表２）に示す。Hereinafter, the heat resistance test is referred to as a solder heat resistance test. The polarization within the range of the present invention (150 ° C.,
(3.0 kV / mm, 30 minutes) are shown in Table 2 together with the piezoelectric ceramic firing temperature (maximum density).

【００１８】[0018]

【表２】 [Table 2]

【００１９】また、（表３）に同上の矩形板状厚みすべ
りモード共振子の−４０℃で３０分間と８０℃で３０分
間保つ温度サイクル前後での共振周波数の変化率（（ｆ
_r−ｆ_ro）／ｆ_roの値；％）と耐湿性（温度６０℃、相
対湿度９０〜９５％の雰囲気下に２００時間さらした後
の共振周波数変化率とｋ₁₅変化率）を示す。Table 3 shows the rate of change of the resonance frequency ((f) before and after the temperature cycle of the above-described rectangular plate-shaped thickness shear mode resonator kept at -40 ° C. for 30 minutes and at 80 ° C. for 30 minutes.
_(r- f _ro ) / f _ro value;%) and moisture resistance (resonance frequency change rate and k ₁₅ change rate after exposure to an atmosphere of a temperature of 60 ° C. and a relative humidity of 90 to 95% for 200 hours).

【００２０】[0020]

【表３】 [Table 3]

【００２１】[0021]

【外１】 [Outside 1]

【００２２】ここで温度サイクルによる共振周波数変動
については｜共振周波数変化率｜≦０．２％のものを良
品と判定した。Here, with respect to the resonance frequency variation due to the temperature cycle, those having | resonance frequency change rate | ≦ 0.2% were determined to be non-defective.

【００２３】また、耐湿性についてはｋ₁₅≧０．３、｜
ｋ₁₅変化率｜≦５％、｜共振周波数変化率｜≦０．２％
のものを良品と判定した。Also, regarding the moisture resistance, k ₁₅ ≧ 0.3, |
k ₁₅ change rate | ≦ 5%, | resonance frequency change rate | ≦ 0.2%
Was determined to be good.

【００２４】以下本実施の形態について表を参照しなが
ら説明する。（表１）〜（表３）によるとα（Ｐｂの一
部をＬａで置換する量）＜０．０２の試料Ｎｏ．２は耐
湿試験で共振周波数変化が大きく（｜共振周波数変化率
｜＞０．２％）、α＞０．０８の試料Ｎｏ．５はキュー
リー温度が低下し、半田耐熱後の脱分極が大きく（｜ｋ
₁₅変化率｜＞５％）かつ共振周波数変化も大きく（｜共
振周波数変化率｜＞０．２％）なるため、αは０．０２
≦α≦０．０８の範囲に限定した。Hereinafter, the present embodiment will be described with reference to a table. According to (Table 1) to (Table 3), sample No. of α (the amount of replacing a part of Pb with La) <0.02. Sample No. 2 showed a large change in resonance frequency in the moisture resistance test (| resonance frequency change rate |> 0.2%) and α> 0.08. In No. 5, the Curie temperature decreases and the depolarization after solder heat resistance is large (| k
₁₅ change rate |> 5%) and a large change in resonance frequency (| resonance frequency change rate |> 0.2%), α is 0.02
≦ α ≦ 0.08.

【００２５】また、β（Ｐｂの一部をＢｉで置換する
量）＜０．０１の試料Ｎｏ．６は半田耐熱後の共振周波
数変化が大きく（｜共振周波数変化率｜＞０．２％）、
β＞０．０５の試料Ｎｏ．９は耐湿性が低下（｜共振周
波数変化率｜＞０．２％）したためβは０．０１≦β≦
０．０５の範囲に限定した。Further, in the case of Sample No. where β (the amount of replacing a part of Pb with Bi) <0.01. No. 6 shows a large change in resonance frequency after solder heat resistance (| resonance frequency change rate |> 0.2%),
Sample No. of β> 0.05. In No. 9, β was 0.01 ≦ β ≦ because the moisture resistance was reduced (| resonance frequency change rate> 0.2%).
The range was limited to 0.05.

【００２６】さらにγ（Ｐｂを化学量論比より過剰に添
加する量）＜０．００２の試料Ｎｏ．１０は耐湿性が劣
る（｜共振周波数変化率｜＞０．２％）ため、γ＞０．
０１の試料Ｎｏ．１３は温度サイクルによる共振周波数
変化が大きくなるため（｜共振周波数変化率｜＞０．２
％）、γは０．００２≦γ≦０．０１の範囲に限定し
た。Further, when the sample No. of γ (the amount of Pb added in excess of the stoichiometric ratio) <0.002, 10 is inferior in moisture resistance (| resonance frequency change rate |> 0.2%), so that γ> 0.
Sample No. 01 No. 13 has a large change in the resonance frequency due to the temperature cycle (| resonance frequency change rate |> 0.2
%) And γ are limited to the range of 0.002 ≦ γ ≦ 0.01.

【００２７】さらにまた、Ａ（ＰＺＴの一部をＰｂ（Ｍ
ｎ_1/2Ｗ_1/2）Ｏ₃で置換する量）＜０．０１である試料
Ｎｏ．１４は半田耐熱前後での共振周波数変化が大きく
（｜共振周波数変化率｜＞０．２％）、Ａ＞０．０５で
ある試料Ｎｏ．１７はキューリー温度の低下が顕著で耐
熱後の脱分極が大きい（ｋ₁₅変化率＞５％）ことからＡ
は０．０１≦Ａ≦０．０５の範囲に限定した。Further, A (part of PZT is replaced with Pb (M
n _1/2 W _1/2 ) Amount to be replaced by O ₃ ) <0.01. Sample No. 14 has a large change in resonance frequency before and after solder heat resistance (| resonance frequency change rate |> 0.2%) and A> 0.05. 17 has a large depolarization after the heat resistance remarkably decrease in the Curie temperature (k ₁₅ change ratio> 5%) since A
Is limited to the range of 0.01 ≦ A ≦ 0.05.

【００２８】また、Ｂ（主成分中のＴ₁量）＜０．５０
である試料Ｎｏ．１８は半田耐熱前後での共振周波数変
化が大きい（｜共振周波数変化率｜＞０．２％）ため、
Ｂ＞０．７４である試料Ｎｏ．２１は圧電性が低下して
いる（ｋ₁₅＜０．３）ため、Ｂは０．５０≦Ｂ≦０．７
４の範囲に限定した。B (the amount of T ₁ in the main component) <0.50
Sample No. No. 18 has a large change in resonance frequency before and after solder heat resistance (| resonance frequency change rate |> 0.2%),
Sample No. B with B> 0.74 In No. 21, B is 0.50 ≦ B ≦ 0.7 because the piezoelectricity is reduced (k ₁₅ <0.3).
4 range.

【００２９】Ｃ（主成分中のＺｒ量）＜０．２５である
試料Ｎｏ．２２は焼結性および圧電性が低下している
（ｋ₁₅＜０．３）ため、Ｃ＞０．４８である試料Ｎｏ．
２５は半田耐熱前後での共振周波数変化が大きい（｜共
振周波数変化率｜＞０．２％）とともに温度サイクルに
よる共振周波数変化率が大きい（｜共振周波数変化率｜
＞０．２％）ため、Ｃは０．２５≦Ｃ≦０．４８の範囲
に限定した。Sample No. C in which C (the amount of Zr in the main component) <0.25. Sample No. 22 in which C> 0.48 was obtained because the sinterability and piezoelectricity were reduced (k ₁₅ <0.3).
No. 25 has a large change in resonance frequency before and after solder heat resistance (| resonance frequency change rate> 0.2%) and a large change rate in resonance frequency due to temperature cycling (| resonance frequency change rate |
> 0.2%), C was limited to the range of 0.25 ≦ C ≦ 0.48.

【００３０】つまり、Ｐｂの一部をＬａで本発明の範囲
内で置換することにより、耐湿性の改善および温度サイ
クルによる共振周波数変化を低減でき、比誘電率ε₁₁ ^T/
ε₀を上昇させることができる。また、Ｐｂの一部をＢ
ｉで本発明の範囲内で置換することにより、半田耐熱後
の共振周波数の変化がさらに低減する。さらに、Ｐｂを
本発明の範囲内で化学量論比より多くすることにより焼
成時のＰｂＯ飛散の影響を低減すると同時に焼結性を高
めることができる。更にまた、ＰＺＴの一部をＰｂ（Ｍ
ｎ_1/2Ｗ_1/2）Ｏ₃で本発明の範囲内で置換することによ
り、焼結温度の低下とｋ₁₅の増加かつ半田耐熱後の共振
周波数経時変化の減少という効果が得られる。That is, by substituting a part of Pb with La within the range of the present invention, it is possible to improve the moisture resistance and reduce the change in the resonance frequency due to the temperature cycle, and the relative dielectric constant ε ₁₁ ^{T /}
ε ₀ can be increased. Also, a part of Pb is B
By substituting i within the range of the present invention, the change in resonance frequency after heat resistance of solder is further reduced. Further, by making Pb larger than the stoichiometric ratio within the range of the present invention, it is possible to reduce the influence of PbO scattering at the time of firing, and at the same time, to enhance sinterability. Furthermore, a part of PZT is converted to Pb (M
By substituting n _1/2 W _1/2 ) O ₃ within the range of the present invention, the effects of lowering the sintering temperature, increasing k ₁₅ , and decreasing the change over time in the resonance frequency after solder heat resistance can be obtained.

【００３１】また、副成分であるＭｎ₃Ｏ₄の添加量につ
いては０．３重量％以下の試料Ｎｏ．２６では半田耐熱
前後での共振周波数変化が大きく（｜共振周波数変化率
｜＞０．２％）かつ温度サイクルによる共振周波数変化
が大きい（０．２％以上）ことから、０．８重量％以上
の試料Ｎｏ．２９では焼結性および圧電性が低下してい
る。（ｋ₁₅＜０．３）ため０．３〜０．８重量％の範囲
に限定した。この範囲でＭｎ₃Ｏ₄を添加することによ
り、半田耐熱後の共振周波数の変化をさらに低減するこ
とができる。The additive amount of Mn ₃ O ₄ as a sub-component was not more than 0.3% by weight. In No. 26, the resonance frequency change before and after solder heat resistance was large (| resonance frequency change rate |> 0.2%) and the resonance frequency change due to temperature cycle was large (0.2% or more), so that it was 0.8% by weight or more. Sample No. In No. 29, sinterability and piezoelectricity are reduced. (K ₁₅ <0.3), the content is limited to the range of 0.3 to 0.8% by weight. By adding Mn ₃ O ₄ in this range, the change in resonance frequency after heat resistance of the solder can be further reduced.

【００３２】分極条件については（表４）に示したよう
に分極温度１３０℃以下（分極条件ア）では分極未飽和
で、分極温度１８０℃以上（分極条件エ）では磁器の比
抵抗が低下し２．５ｋＶ／ｍｍ以上の直流電圧が印加で
きなくなり、また分極電圧２．５ｋＶ／ｍｍ以下（分極
条件オ）では分極未飽和で、分極電圧３．５ｋＶ／ｍｍ
以上（分極条件ケ）では分極中の圧電磁器の歪みが大き
く、圧電磁器割れが多発すると同時に半田耐熱直後の共
振周波数変化率が大きくなる（｜共振周波数変化率｜＞
０．２％）ことから本発明の範囲から除外した。As shown in Table 4, as shown in Table 4, the polarization is not saturated when the polarization temperature is 130 ° C. or less (polarization condition a), and the specific resistance of the porcelain decreases when the polarization temperature is 180 ° C. or more (polarization condition d). A DC voltage of 2.5 kV / mm or more cannot be applied, and when the polarization voltage is 2.5 kV / mm or less (polarization condition 3), the polarization is not saturated and the polarization voltage is 3.5 kV / mm.
In the above (polarization condition), the distortion of the piezoelectric ceramic during polarization is large, and the piezoelectric ceramic cracks frequently occur, and at the same time, the resonance frequency change rate immediately after solder heat resistance increases (| resonance frequency change rate |>).
0.2%) was excluded from the scope of the present invention.

【００３３】[0033]

【表４】 [Table 4]

【００３４】以上のことから本発明の圧電部品に用いる
圧電磁器板１は比較的大きな電気機械結合係数ｋ₁₅と比
誘電率ε₁₁ ^T/ε₀を実現すると同時に良好な耐熱性、耐
湿性と耐熱前後での共振周波数変化と温度サイクル試験
前後での共振周波数変化が小さなものであることがわか
る。From the above, the piezoelectric ceramic plate 1 used for the piezoelectric component of the present invention realizes a relatively large electromechanical coupling coefficient k ₁₅ and a relative dielectric constant ε ₁₁ ^{T /} ε ₀ , and at the same time has good heat resistance and moisture resistance. It can be seen that the change in the resonance frequency before and after the heat resistance and the change in the resonance frequency before and after the temperature cycle test are small.

【００３５】また、上記実施の形態においては、厚みす
べりモード共振子について説明したが、これを用いて形
成したフィルタや発振子等についても同様の効果が得ら
れるものである。In the above-described embodiment, the thickness-shear mode resonator has been described. However, similar effects can be obtained with a filter, an oscillator, and the like formed using the same.

【００３６】[0036]

【発明の効果】以上本発明によると、比較的大きな電気
機械結合係数Ｋ₁₅と比誘電率ε₁₁ ^T/ε ₀を有すると同時
に良好な耐熱性、耐湿性と耐熱前後での共振周波数変化
と温度サイクル試験前後での共振周波数変化が小さな圧
電部品を得ることができる。またこの圧電部品は温度サ
イクル前後での共振周波数変化が小さいので、これを組
み込んだ電子機器の動作は安定したものとなる。また本
発明の圧電部品に用いる圧電磁器板は特に比誘電率ε₁₁
^T/ε₀が大きいことから広帯域のセラミックトラップに
好適なものである。As described above, according to the present invention, relatively large electricity
Mechanical coupling coefficient K₁₅And relative permittivity ε₁₁ ^{T /}ε ₀At the same time as having
Good heat resistance, moisture resistance and resonance frequency change before and after heat resistance
And small change in resonance frequency before and after temperature cycle test
Electrical parts can be obtained. Also, this piezoelectric component
Since the change in resonance frequency before and after the cycle is small,
The operation of the embedded electronic device becomes stable. Also book
The piezoelectric ceramic plate used for the piezoelectric component of the present invention is particularly suitable for the relative dielectric constant ε.₁₁
^{T /}ε₀For large-bandwidth ceramic traps
It is suitable.

【図面の簡単な説明】[Brief description of the drawings]

【図１】本発明の一実施の形態における厚みすべりモー
ド共振子の斜視図FIG. 1 is a perspective view of a thickness-shear mode resonator according to an embodiment of the present invention.

【符号の説明】[Explanation of symbols]

１ 圧電磁器板 ２ 共振電極 1 piezoelectric ceramic plate 2 resonance electrode

───────────────────────────────────────────────────── フロントページの続き (51)Int.Cl.⁷ 識別記号 ＦＩ テーマコート゛(参考） Ｈ０３Ｈ 9/17 Ｈ０１Ｌ 41/22 Ｚ ──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H03H 9/17 H01L 41/22 Z

Claims (2)

【特許請求の範囲】[Claims] 【請求項１】 圧電磁器板と、この圧電磁器板の表面に
設けた対向電極とを備え、前記圧電磁器板は、一般式
（化１）で表される主成分１００重量％に対して、副成
分としてＭｎ₃Ｏ₄を０．３〜０．８重量％添加して形成
した圧電部品。 【化１】 1. A piezoelectric ceramic plate comprising: a piezoelectric ceramic plate; and a counter electrode provided on a surface of the piezoelectric ceramic plate, wherein the piezoelectric ceramic plate is based on 100% by weight of a main component represented by the general formula (Formula 1). the Mn ₃ O ₄ as a sub-component piezoelectric component formed by adding 0.3 to 0.8 wt%. Embedded image 【請求項２】 一般式（化１）で表される主成分１００
重量％に対して、副成分としてＭｎ₃Ｏ₄を０．３〜０．
８重量％添加して成形体を得る第１の工程と、次にこの
成形体を焼成して焼結体を得る第２の工程と、次いでこ
の焼結体を１３０〜１８０℃の温度範囲において２．５
〜３．５ｋＶ／ｍｍの範囲内の直流電界を印加して分極
する第３の工程と、次に所望の共振周波数となるように
前記焼結体を分極方向に対して垂直に切断する第４の工
程と、その後前記焼結体の切断面に対向電極を形成する
第５の工程とを備えた圧電部品の製造方法。2. The main component 100 represented by the general formula (Formula 1)
By weight%, the Mn ₃ O ₄ as a sub-component 0.3 to 0.
A first step of adding a 8% by weight to obtain a molded body, a second step of sintering the molded body to obtain a sintered body, and then heating the sintered body in a temperature range of 130 to 180 ° C. 2.5
A third step of applying a DC electric field in the range of ~ 3.5 kV / mm to polarize, and a fourth step of cutting the sintered body perpendicularly to the polarization direction so as to have a desired resonance frequency. And a fifth step of subsequently forming a counter electrode on the cut surface of the sintered body.