JP2828983B2 - Surface acoustic wave filter and method of manufacturing the same - Google Patents
Surface acoustic wave filter and method of manufacturing the sameInfo
- Publication number
- JP2828983B2 JP2828983B2 JP63033867A JP3386788A JP2828983B2 JP 2828983 B2 JP2828983 B2 JP 2828983B2 JP 63033867 A JP63033867 A JP 63033867A JP 3386788 A JP3386788 A JP 3386788A JP 2828983 B2 JP2828983 B2 JP 2828983B2
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- JP
- Japan
- Prior art keywords
- acoustic wave
- surface acoustic
- wave filter
- back surface
- substrate
- 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 - Lifetime
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- Surface Acoustic Wave Elements And Circuit Networks Thereof (AREA)
Description
【発明の詳細な説明】 〔発明の目的〕 （産業上の利用分野） 本発明は、弾性表面波フィルタおよびその製造方法に
関するものである。DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a surface acoustic wave filter and a method of manufacturing the same.
（従来の技術） 近年、圧電基板の表面を伝搬する弾性表面波を利用し
た表面波フィルタが開発されている。(Prior Art) In recent years, a surface acoustic wave filter using a surface acoustic wave propagating on the surface of a piezoelectric substrate has been developed.
この表面波フィルタは、第６図に示すように圧電基板
（１）の表面上にくし状電極（２），（３）により構成
される入出力トラスデューサ（６），（７）において加
えられた電気信号が圧電基板（１）の表面を伝搬する弾
性表面波に変換され、出力トランスデューサ（７）によ
って再び電気信号に変換されるものである。しかし、こ
の弾性表面波フィルタは入力トランスデューサ（６）か
ら弾性表面波のほかにも圧電基板（１）の中を伝わるバ
ルク波をも放射する。そしてこのバルク波が圧電基板
（１）の平らな裏面で反射されることにより、再び表面
において出力トランスデューサ（７）に到達して検出さ
れる。そのため、弾性表面波フィルタの特性にスプリア
スやリップルを生じ、テレビに組み込んだ場合、画像に
ゴーストを発生させたり、画像を不安定にして、セット
の性能を悪化させていた。This surface acoustic wave filter is applied to input / output transducers (6) and (7) composed of comb electrodes (2) and (3) on the surface of a piezoelectric substrate (1) as shown in FIG. The electric signal is converted into a surface acoustic wave propagating on the surface of the piezoelectric substrate (1), and is again converted into an electric signal by the output transducer (7). However, this surface acoustic wave filter radiates not only a surface acoustic wave but also a bulk wave transmitted through the piezoelectric substrate (1) from the input transducer (6). Then, this bulk wave is reflected by the flat back surface of the piezoelectric substrate (1), and reaches the output transducer (7) again on the front surface to be detected. For this reason, spurious and ripples are generated in the characteristics of the surface acoustic wave filter, and when the filter is incorporated into a television, a ghost is generated in the image or the image becomes unstable, thereby deteriorating the performance of the set.
そこで、これらを防止するために、従来は実公昭57−
33627号公報等が知られ、第７図に示すように、圧電基
板（１）の裏面に溝や穴（８）を不規則で、かつ多数設
けることを行っていた。Therefore, in order to prevent these, the conventional
No. 33627 is known, and as shown in FIG. 7, irregular and many grooves and holes (8) are provided on the back surface of the piezoelectric substrate (1).
（発明が解決しようとする課題） しかしながら従来の裏面加工は、ランダムに粗したり
していたため機械的強度が十分得られなかった。さらに
バルク波の抑制についても改善の余地があった。(Problems to be Solved by the Invention) However, in the conventional back surface processing, mechanical strength was not sufficiently obtained due to random roughening. There is also room for improvement in the suppression of bulk waves.
本発明の目的は、上記問題点を解決しバルク波の発生
を低下させ、かつ弾性表面波用基板の強度を保つことの
できる弾性表面波フィルタおよびその製造方法を提供す
ることにある。SUMMARY OF THE INVENTION An object of the present invention is to provide a surface acoustic wave filter capable of solving the above problems, reducing the generation of bulk waves, and maintaining the strength of the surface acoustic wave substrate, and a method of manufacturing the same.
（課題を解決するための手段） 本発明は、圧電性酸化物単結晶からなる基板に形成さ
れたくし形電極を有する面に対し反対の面である裏面に
くぼみを形成してなる弾性表面波フィルタにおいて、裏
面の表面粗さRaを0.5μｍ≦Ra≦3.0μｍとし、かつくぼ
みの深さｄと基板の厚さｔとの関係が0.1≦d/t≦0.6,ピ
ッチp0.3≦ｐ≦5.0mmである弾性表面波フィルタであ
る。また、この弾性表面波フィルタの弾性表面波用基板
の裏面をウレタンゴム膜でマスクし、その後ホーニング
することによりくぼみを形成する弾性表面波フィルタの
製造方法にある。(Means for Solving the Problems) The present invention provides a surface acoustic wave filter having a depression formed on a back surface opposite to a surface having a comb-shaped electrode formed on a substrate made of a piezoelectric oxide single crystal. In the above, the surface roughness Ra of the back surface is 0.5 μm ≦ Ra ≦ 3.0 μm, and the relationship between the depth d of the recess and the thickness t of the substrate is 0.1 ≦ d / t ≦ 0.6, and the pitch p0.3 ≦ p ≦ 5.0. mm is a surface acoustic wave filter. Also, there is provided a method of manufacturing a surface acoustic wave filter in which a back surface of a surface acoustic wave substrate of the surface acoustic wave filter is masked with a urethane rubber film and then horned to form a depression.
（作用） このように構成された弾性表面波フィルタは、弾性表
面波と同時に入出力トランスデューサから圧電基板中へ
放射されたバルク波が、表面に形成された一定のピッチ
及び寸法を有するくぼみと表面粗さRaを施すことによ
り、乱反射され、それぞれ乱反射されたバルク波相互の
位相差を発生により、お互いに打消し合うように働き、
出力トランスデューサへ到達するバルク波は大幅に減少
する。このため、特性上スプリアスやリップル波は生じ
なくなる。(Operation) In the surface acoustic wave filter configured as described above, the bulk wave radiated from the input / output transducer into the piezoelectric substrate at the same time as the surface acoustic wave is formed by the depression and the surface having a constant pitch and size formed on the surface. By applying the roughness Ra, irregularly reflected, each irregularly reflected bulk wave generates a phase difference between each other, and works to cancel each other out,
Bulk waves reaching the output transducer are greatly reduced. For this reason, spurious and ripple waves do not occur due to characteristics.
第２図に不要波レベルと表面粗さとの関係を示し、同
図から明らかなように、表面粗さRaが0.5μｍ以上にな
ると不要波レベルが低下し、効果がある。また、第３図
は不要波レベルと（くぼみの深さ）d/（基板の厚さ）ｔ
との関係を示し、この値が0.1乃至0.6の範囲であれば不
要波レベルの低下を実現することができる。なお、歩留
りを考慮すると、第４図からわかるように、0.1に近い
値の方がより好ましい。さらに、くぼみのピッチは第５
図に示す通り、0.3mm乃至5.0mmの範囲であれば不要波レ
ベルを低下させる効果があるが、0.3mmに近い値の方が
より好ましいことがわかる。FIG. 2 shows the relationship between the spurious wave level and the surface roughness. As is clear from FIG. 2, when the surface roughness Ra is 0.5 μm or more, the spurious wave level is reduced, which is effective. FIG. 3 shows an unnecessary wave level and (depth of a hollow) d / (thickness of a substrate) t.
When this value is in the range of 0.1 to 0.6, the unnecessary wave level can be reduced. In consideration of the yield, a value closer to 0.1 is more preferable, as can be seen from FIG. Furthermore, the pitch of the depression is 5th.
As shown in the figure, if it is in the range of 0.3 mm to 5.0 mm, there is an effect of lowering the unnecessary wave level, but it is understood that a value closer to 0.3 mm is more preferable.
（実 施 例） 以下、本発明の弾性表面波フィルタの実施例を図面を
参照して詳細に説明する。第１図は、厚さ（ｔ）である
基板（１）の裏面に表面粗さ（５）とピッチ（ｐ），深
さ（ｄ）を有するくぼみ（４）を形成し、くし状電極
（２），（３）を備えている弾性表面波フィルタを示
し、基板（１）や裏面加工の条件を変えて以下の通り評
価した。(Example) Hereinafter, an example of a surface acoustic wave filter of the present invention will be described in detail with reference to the drawings. FIG. 1 shows that a depression (4) having a surface roughness (5), a pitch (p) and a depth (d) is formed on the back surface of a substrate (1) having a thickness (t), and a comb-shaped electrode ( A surface acoustic wave filter having 2) and (3) is shown, and was evaluated as follows by changing the conditions for processing the substrate (1) and the back surface.
実施例−１ 両面ラップされた128゜Ｙ−LiNbO3の厚さ0.55mmtのウ
エハの裏面にスクリーン印刷でウレタンゴム液により、
ピッチ0.5mmでくぼみの寸法0.25mm×0.25mmのマスク印
刷をする。Example-1 A double-sided wrapped 128 ° Y-LiNbO 3 wafer having a thickness of 0.55 mmt was screen-printed with a urethane rubber liquid on the back surface.
Print a mask with a pitch of 0.5mm and a recess size of 0.25mm x 0.25mm.
マスクはオリエンテーションフラットに対し45゜の傾
きの配列でセットする。次いで、印刷終了後、裏面をア
ランダム♯240の砥粒でホーニング操作を施し、深さ120
μｍのくぼみを形成する。ホーニング後、マスクを剥離
してフッ硝酸エッチングを30分間行う。エッチング後
は、さらに裏面をアランダム♯100の砥粒でホーニング
して表面を粗らし、フッ硝酸でエッチングする。最終的
に裏面の表面粗さRaは2.0μｍであった。その後、表面
側をポリッシングして仕上げる。The mask is set at an inclination of 45 ° with respect to the orientation flat. Next, after printing, the back surface is subjected to a honing operation with Alundum # 240 abrasive grains to a depth of 120.
Form a depression of μm. After honing, the mask is peeled off and etching with hydrofluoric nitric acid is performed for 30 minutes. After the etching, the back surface is further honed with Alundum # 100 abrasive grains to roughen the surface, and then etched with hydrofluoric nitric acid. Finally, the surface roughness Ra of the back surface was 2.0 μm. Then, the surface side is polished and finished.
このウエハを用い、テレビ用IFフィルタを試作したと
ころ、従来フィルタの高帯域にバルク波によるノイズが
−40dBまであったが、本発明は−51dBまで低下した。ま
た、デバイスの歩留りが30％から75％まで向上し、強度
についても向上がみられた。When a TV IF filter was prototyped using this wafer, the noise due to bulk waves was up to −40 dB in the high band of the conventional filter, but the present invention was reduced to −51 dB. In addition, device yields have increased from 30% to 75%, and strength has also improved.
実施例−２ 両面ラップされた128゜Ｙ−LiNbO3の厚さ0.55mmtのウ
エハの裏面をアランダム♯100の砥粒で全面をホーニン
グ加工する。その後、フッ硝酸エッチングを30分間行
う。ウエハの裏面にスクリーン印刷でウレタンゴム膜を
ピッチ0.5mmで、くぼみの寸法0.25mm×0.25mmのマスク
印刷をする。マスクは、オリテンテーションフラットに
対し45゜の傾きの配列でセットする。印刷終了後、裏面
をアランダム♯240の砥粒でホーニング操作を施し、深
さ120μｍのくぼみを形成する。ホーニング後、マスク
を剥離してフッ硝酸エッチングを30分間行う。最終的
に、裏面の表面粗さRaは2.5μｍであった。その後、表
面側をポリッシングして仕上げる。Example 2 The back surface of a double-sided wrapped 128 ° Y-LiNbO 3 wafer having a thickness of 0.55 mmt is entirely honed with abrasive grains of Alundum # 100. Then, hydrofluoric-nitric acid etching is performed for 30 minutes. A urethane rubber film is printed on the back surface of the wafer by screen printing at a pitch of 0.5 mm and a mask with a recess size of 0.25 mm x 0.25 mm. The mask is set at an inclination of 45 ° with respect to the orientation flat. After the printing is completed, a honing operation is performed on the back surface with Alundum # 240 abrasive grains to form a recess having a depth of 120 μm. After honing, the mask is peeled off and etching with hydrofluoric nitric acid is performed for 30 minutes. Finally, the surface roughness Ra of the back surface was 2.5 μm. Then, the surface side is polished and finished.
このウエハを、実施例−１と同様にして評価したとこ
ろ、従来のフィルタの高帯域にバルク波によるノイズが
−40dBまであったが、本発明のフィルタは−51dBまで低
下した。また、デバイスの歩留りが30％から85％まで向
上し、実施例−１と同様の効果が得られた。When this wafer was evaluated in the same manner as in Example 1, the noise due to the bulk wave was up to −40 dB in the high band of the conventional filter, but the filter of the present invention was reduced to −51 dB. Further, the yield of the device was improved from 30% to 85%, and the same effect as that of Example-1 was obtained.
実施例−３ 両面ラップされたＸ−LiTaO3の厚さ0.55mmtのウエハ
の裏面にスクリーン印刷により、ウレタンゴム液で、ピ
ッチ0.5mmでくぼみの寸法0.25mm×0.25mmのマスク印刷
をする。このマスクは、オリエンテーションフラットに
対し45゜の傾きの配列でセットする。印刷終了後は、裏
面をアランダム♯240の砥粒でホーニング操作を施し、
深さ120μｍのくぼみを形成する。ホーニング後、マス
クを剥離してフッ硝酸エッチングを30分間行う。エッチ
ング後、さらに裏面をアランダム♯100の砥粒でホーニ
ングして粗らし、フッ硝酸でエッチングする。最終的
に、表面の表面粗さRaは2.0μｍであった。その後、裏
面側をポリッシングして仕上げる。By screen printing on the rear surface of the wafer thickness 0.55mmt of X-LiTaO 3 which are examples -3 double side lapping, a urethane rubber solution, the mask printing size 0.25 mm × 0.25 mm of the recess at a pitch 0.5 mm. This mask is set in an array having an inclination of 45 ° with respect to the orientation flat. After printing, the back side is subjected to honing operation with Alundum # 240 abrasive grains,
A depression having a depth of 120 μm is formed. After honing, the mask is peeled off and etching with hydrofluoric nitric acid is performed for 30 minutes. After the etching, the back surface is further honed with Alundum # 100 abrasive grains to roughen the surface, and then etched with hydrofluoric nitric acid. Finally, the surface roughness Ra of the surface was 2.0 μm. Then, the back side is polished and finished.
このウエハを実施例−１と同様にして評価したとこ
ろ、従来のフィルタの高帯域にバルク波によるノイズが
−40dBまであったが、本発明のフィルタでは−50dBまで
低下した。When this wafer was evaluated in the same manner as in Example 1, the noise due to the bulk wave was up to -40 dB in the high band of the conventional filter, but was reduced to -50 dB in the filter of the present invention.
また、デバイスの歩留りが、50％から85％まで向上
し、実施例−１と同様の効果が得られた。Further, the yield of the device was improved from 50% to 85%, and the same effect as in Example-1 was obtained.
実施例−４ 両面ラップされたＸ−LiTaO3の厚さ0.55mmtのウエハ
の裏面をアランダム♯100の砥粒で全面をホーニング加
工する。その後、フッ硝酸エッチングを30分間行う。ウ
エハの表面はスクリーン印刷によりウレタンゴム液でピ
ッチ0.5mm、くぼみの寸法0.25mm×0.25mmのマスク印刷
をする。マスクは、オリエンテーションフラットに対し
45゜の傾きの配列でセットする。印刷終了後、裏面にア
ランダム♯240の砥粒でホーニング操作を施し、深さ120
μｍのくぼみを形成する。ホーニング後マスクを剥離し
てフッ硝酸エッチングを30分間行う。最終的に裏面の表
面粗さRaは2.1μｍとなった。Example-4 The back surface of a double-sided wrapped X-LiTaO 3 wafer having a thickness of 0.55 mmt is entirely honed with Alundum # 100 abrasive grains. Then, hydrofluoric-nitric acid etching is performed for 30 minutes. The surface of the wafer is screen-printed with a urethane rubber solution to print a mask with a pitch of 0.5 mm and the dimensions of the recesses of 0.25 mm x 0.25 mm. Mask is oriented flat
Set in a 45 ° tilt array. After printing, perform honing operation on the back side with Arandom # 240 abrasive grains to a depth of 120
Form a depression of μm. After the honing, the mask is peeled off and hydrofluoric-nitric acid etching is performed for 30 minutes. Finally, the surface roughness Ra of the back surface was 2.1 μm.
その後、表面側をポリッシングして仕上げる。 Then, the surface side is polished and finished.
このウエハを実施例−１と同様にして評価したとこ
ろ、従来のフィルタの高帯域にバルク波によるノイズが
−42dBまであったが、本発明のフィルタでは、−52dBま
で低下した。When this wafer was evaluated in the same manner as in Example 1, the noise due to the bulk wave was up to -42 dB in the high band of the conventional filter, but was reduced to -52 dB in the filter of the present invention.
また、デバイス歩留りが、45％から85％まで向上し、
実施例−１と同様の効果が得られた。In addition, device yield increased from 45% to 85%,
The same effect as in Example 1 was obtained.
実施例−５ 両面ラップされた128゜Ｙ−LiNbO3の厚さ0.55mmtのウ
エハの裏面に紫外線硬化型のウレタンゴム液を均一に塗
布する。そしてその上にピッチ0.5mm、くぼみの寸法0.2
5mm×0.25mmのパターンを形成したフィルムを置き、数
分間紫外線による露光を行う。くぼみのパターンは、オ
リエンテーションフラットに対し45゜の傾きの配列でセ
ットする。その後、裏面をアランダム♯240の砥粒でホ
ーニング操作を施し、深さ120μｍのくぼみを形成す
る。ホーニング後は、実施例−１と同様の方法で行っ
た。Example-5 A UV curable urethane rubber solution is uniformly applied to the back surface of a double-sided wrapped 128 ° Y-LiNbO 3 wafer having a thickness of 0.55 mmt. And on top of that, pitch 0.5mm, recess size 0.2
A film on which a pattern of 5 mm × 0.25 mm is formed is placed and exposed to ultraviolet light for several minutes. The depression pattern is set in an array with a 45 ° inclination to the orientation flat. Thereafter, the back surface is subjected to a honing operation using abrasive grains of Alundum # 240 to form a recess having a depth of 120 μm. After honing, the same procedure as in Example 1 was performed.
最終的な裏面の表面粗さRaは2.0μｍとなった。その
結果、従来のフィルタの高帯域にバルク波によるノイズ
が−40dBまであったが、本発明のフィルタは−51dBまで
低下した。また、デバイス歩留りが30％から80％まで向
上し、実施例−１と同様の効果が得られた。The final surface roughness Ra of the back surface was 2.0 μm. As a result, the noise due to the bulk wave was up to -40 dB in the high band of the conventional filter, but was reduced to -51 dB in the filter of the present invention. Further, the device yield was improved from 30% to 80%, and the same effect as in Example 1 was obtained.
実施例−６ 両面ラップされたＸ−LiTaO3の厚さ0.55mmtのウエハ
の裏面に紫外線硬化型のウレタンゴム液を均一に塗布す
る。その上に、ピッチ0.5mm,くぼみの寸法を0.25mm×0.
25mmのパターンを形成したフィルムを置き、数分間紫外
線による露光を行う。くぼみのパターンは、オリエンテ
ーションフラットに対し45゜の傾きの配列でセットす
る。その後、裏面をアランダム♯240の砥粒でホーニン
グ操作を施し、深さ120μｍのくぼみを形成する。ホー
ニング後は、実施例−３と同様の方法で行った。裏面の
表面粗さRaは2.0μｍとなり、ノイズも−40dBから−50d
Bまで低下した。さらに、デバイス歩留りが50％から87
％まで向上した。Example -6 An ultraviolet-curable urethane rubber liquid is uniformly applied to the back surface of a 0.55-mm-thick wafer of X-LiTaO 3 wrapped on both sides. On top of that, the pitch is 0.5 mm and the size of the recess is 0.25 mm x 0.
A film having a pattern of 25 mm is placed and exposed to ultraviolet light for several minutes. The depression pattern is set in an array with a 45 ° inclination to the orientation flat. Thereafter, the back surface is subjected to a honing operation using abrasive grains of Alundum # 240 to form a recess having a depth of 120 μm. After honing, the same method as in Example 3 was performed. The surface roughness Ra of the back side is 2.0 μm, and the noise is also -40 dB to -50 d
It dropped to B. In addition, device yield from 50% to 87
%.
なお、本実施例では一定のピッチ及び寸法を有するく
ぼみを形成するものに限ったが、一定の長さを有する連
続したくぼみまたは溝を形成したものであっても良い。Although the present embodiment is limited to the formation of the pits having a constant pitch and size, the pits may be formed of continuous pits or grooves having a fixed length.
本発明によれば、弾性表面波用基板の裏面に一定の表
面粗さと一定のピッチ，寸法を有するくぼみを形成する
ので、バルク波を有効に抑制することができると共に機
械的強度も十分保たれる。According to the present invention, since a depression having a constant surface roughness and a constant pitch and size is formed on the back surface of the surface acoustic wave substrate, the bulk wave can be effectively suppressed and the mechanical strength is sufficiently maintained. It is.
第１図は本発明の弾性表面波フィルタを示す要部拡大断
面図、第２図は本発明の弾性表面波フィルタを用いて得
られた不要波レベルと表面粗さとの関係をグラフで示す
図、第３図は本発明の評価として不要波レベルとくぼみ
の深さ（ｄ）／基板の厚さ（ｔ）との関係をグラフで示
す図、第４図は本発明の評価として歩留りとくぼみの深
さ（ｄ）／基板の厚さ（ｔ）との関係をグラフで示す
図、第５図は本発明の評価として不要波レベルとピッチ
（ｐ）との関係をグラフで示す図、第６図は従来の弾性
表面波フィルタを示す平面図、第７図は従来の弾性表面
波フィルタを示す縦断面図である。 （１）……基板、（２），（３）……くし状電極 （４）……くぼみ、（５）……表面粗さ （ｐ）……ピッチ、（ｄ）……深さ （ｔ）……厚さFIG. 1 is an enlarged sectional view of a principal part showing a surface acoustic wave filter of the present invention, and FIG. 2 is a graph showing a relationship between an unnecessary wave level and a surface roughness obtained by using the surface acoustic wave filter of the present invention. FIG. 3 is a graph showing the relationship between the spurious wave level and the depth of the hollow (d) / the thickness of the substrate (t) as an evaluation of the present invention, and FIG. 4 is the yield and the hollow as the evaluation of the present invention. FIG. 5 is a graph showing the relationship between the depth (d) / thickness (t) of the substrate, and FIG. 5 is a graph showing the relationship between the unwanted wave level and the pitch (p) as an evaluation of the present invention. FIG. 6 is a plan view showing a conventional surface acoustic wave filter, and FIG. 7 is a longitudinal sectional view showing a conventional surface acoustic wave filter. (1) ... substrate, (2), (3) ... comb-shaped electrode (4) ... recess, (5) ... surface roughness (p) ... pitch, (d) ... depth (t) )……thickness
───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特開 昭59−47822（ＪＰ，Ａ) 特開 昭60−104939（ＪＰ，Ａ) 特開 昭54−75290（ＪＰ，Ａ) 特開 昭55−105427（ＪＰ，Ａ) 特開 昭60−153616（ＪＰ，Ａ) 特開 昭50−56224（ＪＰ，Ａ) 実開 昭61−189621（ＪＰ，Ｕ) ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-59-47822 (JP, A) JP-A-60-104939 (JP, A) JP-A-54-75290 (JP, A) 105427 (JP, A) JP-A-60-153616 (JP, A) JP-A-50-56224 (JP, A) Japanese Utility Model Application Sho 61-189621 (JP, U)
Claims (2)
れたくし形電極を有する面に対し反対の面である裏面に
くぼみを形成してなる弾性表面波フィルタにおいて、 前記裏面の表面粗さRaを0.5μｍ≦Ra≦3.0μｍとし、か
つ前記くぼみの深さｄと基板の厚さｔとの関係が0.1≦d
/t≦0.6、ピッチp0.3mm≦ｐ≦5.0mmであることを特徴と
する弾性表面波フィルタ。1. A surface acoustic wave filter having a depression formed on a back surface opposite to a surface having a comb-shaped electrode formed on a substrate made of a piezoelectric oxide single crystal, wherein the surface roughness of the back surface is Ra is 0.5 μm ≦ Ra ≦ 3.0 μm, and the relationship between the depth d of the depression and the thickness t of the substrate is 0.1 ≦ d.
A surface acoustic wave filter wherein /t≦0.6 and a pitch p0.3 mm ≦ p ≦ 5.0 mm.
でマスクし、その後ホーニングすることによりくぼみを
形成することを特徴とする請求項１記載の弾性表面波フ
ィルタの製造方法。2. A method for manufacturing a surface acoustic wave filter according to claim 1, wherein the back surface of the surface acoustic wave substrate is masked with a urethane rubber film, and then the recess is formed by honing.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63033867A JP2828983B2 (en) | 1988-02-18 | 1988-02-18 | Surface acoustic wave filter and method of manufacturing the same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63033867A JP2828983B2 (en) | 1988-02-18 | 1988-02-18 | Surface acoustic wave filter and method of manufacturing the same |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01209811A JPH01209811A (en) | 1989-08-23 |
| JP2828983B2 true JP2828983B2 (en) | 1998-11-25 |
Family
ID=12398457
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63033867A Expired - Lifetime JP2828983B2 (en) | 1988-02-18 | 1988-02-18 | Surface acoustic wave filter and method of manufacturing the same |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2828983B2 (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0897675A (en) | 1994-09-28 | 1996-04-12 | Canon Inc | Surface acoustic wave element and its manufacture and communication equipment using it |
| US7382081B2 (en) | 2006-02-27 | 2008-06-03 | Matsushita Electric Industrial Co., Ltd. | Electronic component package |
| JP2008283337A (en) * | 2007-05-09 | 2008-11-20 | Epson Toyocom Corp | Surface acoustic wave device, and manufacturing method of surface acoustic wave device and wafer |
| JP6247054B2 (en) * | 2013-09-02 | 2017-12-13 | 日本碍子株式会社 | Elastic wave device and manufacturing method thereof |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1438777A (en) * | 1973-09-04 | 1976-06-09 | Mullard Ltd | Electromechanical propagation devices and the manufacture thereof |
| JPS5475290A (en) * | 1977-11-29 | 1979-06-15 | Fujitsu Ltd | Linbo3 substrate for elastic surface wave |
| JPS55105427A (en) * | 1979-02-06 | 1980-08-13 | Kyocera Corp | Surface wave device |
| JPS60104939A (en) * | 1983-11-14 | 1985-06-10 | Asahi Chem Ind Co Ltd | Mask transfer material for sand blast |
| JPS60153616A (en) * | 1984-01-24 | 1985-08-13 | Toshiba Corp | Manufacture of surface acoustic wave element |
| JPS61189621U (en) * | 1985-05-15 | 1986-11-26 |
-
1988
- 1988-02-18 JP JP63033867A patent/JP2828983B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH01209811A (en) | 1989-08-23 |
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