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JP4111731B2 - Method for forming excitation electrode on quartz piece - Google Patents

Method for forming excitation electrode on quartz piece Download PDF

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Publication number
JP4111731B2
JP4111731B2 JP2002082292A JP2002082292A JP4111731B2 JP 4111731 B2 JP4111731 B2 JP 4111731B2 JP 2002082292 A JP2002082292 A JP 2002082292A JP 2002082292 A JP2002082292 A JP 2002082292A JP 4111731 B2 JP4111731 B2 JP 4111731B2
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Japan
Prior art keywords
side plate
plate surface
electrode
crystal piece
forming
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 - Fee Related
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JP2002082292A
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Japanese (ja)
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JP2003282985A (en
Inventor
金 真 栄 土
葉 亜 紀 雄 千
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nihon Dempa Kogyo Co Ltd
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Nihon Dempa Kogyo Co Ltd
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  • Piezo-Electric Or Mechanical Vibrators, Or Delay Or Filter Circuits (AREA)

Description

【0001】
【産業上の利用分野】
本発明は、光透過性を有する水晶片の表裏板面(一側及び他側板面)に対面して同じ形状の励振電極を正確に形成することのできる水晶片に対する励振電極の形成方法に関する。
【0002】
【従来の技術】
従来たとえばモノリシック水晶フィルタ等では、板状に成形した水晶片の表裏板面に相対面して、水晶片を励振する励振電極を形成することが行われている。
【0003】
このような励振電極を形成する場合、一般的には水晶片の上に所望の電極形状に対応した透孔を形成した蒸着マスクを載せる。そして、真空中に置いた蒸着源に蒸着マスクを介在して水晶片を対向させて、蒸着マスクに対応した形状に電極を蒸着するようにしている。 蒸着源は、たとえばアルミ、銀等の蒸着金属を加熱して金属蒸気を発生させるようにしている。
【0004】
しかしながら、たとえばモノリシック水晶フィルタの場合、著しく高周波化、小型化の傾向がある。このため、たとえば周波数130MHzの小型のフィルタでは、表面実装型の容器の外形形状は2.5mmx2.0mm、この容器に納める水晶片の大きさは1.5mmx0.8mm程度のものがある。
【0005】
さらにこのように小さな水晶片の板面に0.4mm角程度の電極を正確に対面させて形成する必要があり、蒸着マスクのわずかなズレによって電極位置がズレて所望のフィルタ特性を得られなくなる。
【0006】
一般に蒸着マスクは水晶片の外形形状に対応した多数の透孔を穿設した金属板からなる中枠の両側に、金属薄板に蒸着で形成する電極形状に対応した透孔を穿設したマスク板を添設する。そして中枠の透孔に、それぞれ水晶片を配置して、両側からマスク板で挟み込み、中枠とマスク板を重ね合わせた状態で、複数箇所をネジ止めして蒸着を行うようにしている。
【0007】
しかしながら、このような構造では形状が極めて小さな水晶片を所定位置に正確に保持し、かつマスク板を所定の位置に正確に置くことは極めて困難であり、蒸着を行う際の工数もかかり、しかも電極位置がズレて、設計段階で予定した所望のフィルタ特性を得られず、不良品が多発する問題があった。
【0008】
【発明が解決しようとする課題】
本発明は上記の事情に鑑みてなされたもので、光透過性を有する水晶片の表裏板面(一側及び他側版面)に相対面して同じ形状の励振電極を正確に形成することのできる電極の形成方法を提供することを目的とするものである。
【0009】
【課題を解決するための手段】
本発明の請求項1は、一側及び他側板面に相対面した第1と第2の励振電極を有する光透過性とした水晶片前記一側板面に蒸着によって所望の形状の前記第1励振電極を形成する工程と、
前記水晶片前記他側板面に感光性のレジスト膜を形成する工程と、
前記レジスト膜に前記水晶片前記一側板面から前記第1励振電極の形成部位をフォトマスクとして光を照射する工程と、
前記レジスト膜の感光部分又は非感光部分を除去して前記第1励振電極に対向した前記水晶片の前記他側板面を露出する工程と、
前記水晶片前記他側板面に残ったレジスト膜を含めて、前記他側板面の全面に蒸着によって電極を形成する工程と、
前記水晶片前記他側板面のレジスト膜及び前記レジスト膜上の電極を除去して、前記他側板面に前記第2励振電極を形成する工程と、
からなることを特徴とする水晶片に対する励振電極の形成方法である。
【0010】
そして請求項2は、請求項1に記載のものにおいて、前記レジスト膜は感光部分が硬化し、前記他側板面の非感光部分に電極を蒸着したことを特徴とする水晶片に対する励振電極の形成方法であり、請求項3は請求項1に記載のものにおいて、前記レジスト膜は非感光部分が硬化し、前記他側板面の感光部分に電極を蒸着により形成したことを特徴とする水晶片に対する励振電極の形成方法である。
【0011】
さらに請求項4は請求項1に記載のものにおいて、前記水晶片はモノリシック水晶フィルタであることを特徴とする水晶片に対する励振電極の形成方法である。
【0012】
【発明の実施の形態】
以下、本発明の実施の形態をモノリシック水晶フィルタ用の水晶片に対する励振電極の形成方法を例として図1に示すフローチャート、図2に示す厚みを誇張した側面図を参照して詳細に説明する。まず1で「START」し、続いて2で光透過性を有する水晶片11の「一側板面に第1例振電極12を蒸着」する。
【0013】
この第1例振電極12は、たとえばアルミ、銀等の金属薄膜のため光を遮断するのに対して第1例振電極の非形成部位は水晶であり光を透過する。そして3で水晶片11の「他側板面の全面にレジストを塗布」する。この場合、レジストの光学的特性に応じて他側板面に形成する第2例振電極の形成位置が定まる。
【0014】
すなわち、他側板面の第2励振電極は、レジスト膜の感光部分が硬化するものを用いた場合は非感光部位に形成され、レジスト膜の非感光部分が硬化するものを用いた場合は感光部位に形成される。したがってモノリシック水晶フィルタの場合は、表裏板面(一側及び他側板面)第1及び第2の励振電極を正確に対面して形成する必要があり、レジスト膜は感光部分が硬化するものを用いる。
【0015】
そして4で「一側板面から光を照射」し、光が透過した他側板面の領域を硬化レジストとし、第1例振電極に対向した他側板面の領域を非硬化レジストとする。続いて5で第1例振電極に対向した他側板面の「非硬化レジストの除去」を行う。そして6で「他側板面に電極を蒸着」し、7で「硬化したレジストの除去」を行う。この場合、他側板面の全面に電極を蒸着するが、これによって形成した金属薄膜のうち、硬化したレジストの上に蒸着した部分は、この硬化したレジストを除去する際に同時に除去される。
【0016】
このようにすれば、水晶片11の一側板面に形成した第1例振電極をマスクとして他側板面のレジストを露光し、レジスト膜の非硬化部分を除去して他側板面に電極を蒸着している。 そして他側板面に残った硬化したレジスト膜及びその上の電極を除去するようにしている。 したがって、一側板面の第1例振電極の電極形状に正確に対応した形状の第2例振電極を他側板面に形成することができる。
【0017】
さらには、微小な寸法の水晶片を蒸着マスクに納める作業も不要になり、作業を大幅に簡素化することができる。 したがって製造コストを低減し、しかも正確に所望の位置に第1及び第2の励振電極を形成することができ、たとえばモノリシック水晶フィルタの場合は設計時に予定した電気的特性を実現することが出来る。
【0018】
しかして、上記実施例によれば、特に形状の小さな、光透過性を有する水晶片の表裏板面に、正確に対面した状態に、第1及び第2の励振電極を形成することができ、しかも加工も容易で高い寸法精度を容易に実現することができる。
【0019】
【発明の効果】
以上詳述したように本発明によれば、光透過性を有する水晶片の表裏板面(一側及び他側板面)に相対面して同じ形状の第1及び第2の電極を正確に形成することができる水晶片に対する励振電極の形成方法を提供することができる。
【図面の簡単な説明】
【図1】 本発明の一実施形態のフローチャートである。
【図2】 本発明の一実施態様の厚みを誇張した側面図である。
【符号の説明】
11 ・・ 水晶片
12 ・・ 電極
[0001]
[Industrial application fields]
The present invention relates to a method for forming an excitation electrode for a crystal piece that can accurately form an excitation electrode having the same shape by facing the front and back plate surfaces (one side and the other side plate surface) of the crystal piece having optical transparency.
[0002]
[Prior art]
Conventionally, for example, in a monolithic crystal filter, an excitation electrode for exciting the crystal piece is formed so as to face the front and back plate surfaces of the crystal piece formed into a plate shape.
[0003]
When such an excitation electrode is formed, a vapor deposition mask in which a through hole corresponding to a desired electrode shape is generally placed on a crystal piece. Then, an electrode is deposited in a shape corresponding to the deposition mask, with the crystal piece facing the deposition source placed in a vacuum with a deposition mask interposed therebetween. For example, the vapor deposition source heats a vapor deposition metal such as aluminum or silver to generate a metal vapor.
[0004]
However, for example, in the case of a monolithic crystal filter, there is a tendency for remarkably high frequency and miniaturization. For this reason, for example, in a small filter having a frequency of 130 MHz, the surface mount type container has an outer shape of 2.5 mm × 2.0 mm, and the size of a crystal piece accommodated in the container is about 1.5 mm × 0.8 mm.
[0005]
Furthermore , it is necessary to form electrodes with a size of about 0.4 mm square on the plate surface of such a small crystal piece so that the electrode position is shifted due to slight displacement of the vapor deposition mask, and desired filter characteristics can be obtained. Disappear.
[0006]
In general, a vapor deposition mask is a mask in which through holes corresponding to the electrode shape formed by vapor deposition on a metal thin plate are formed on both sides of an inner frame made of a metal plate having a large number of through holes corresponding to the outer shape of a crystal piece. Attach a board. Then, crystal pieces are respectively disposed in the through holes of the inner frame, sandwiched between the mask plates from both sides, and in a state where the inner frame and the mask plate are overlapped with each other, a plurality of positions are screwed to perform vapor deposition.
[0007]
However, in such a structure, it is extremely difficult to accurately hold a crystal piece having a very small shape in a predetermined position and to accurately place a mask plate in a predetermined position, and it takes a lot of man-hours for vapor deposition. There is a problem in that the electrode position is shifted, the desired filter characteristics planned in the design stage cannot be obtained, and defective products occur frequently.
[0008]
[Problems to be solved by the invention]
The present invention has been made in view of the above circumstances, and is capable of accurately forming excitation electrodes having the same shape facing the front and back plate surfaces (one side and the other side plate surfaces) of a light-transmitting crystal piece . An object of the present invention is to provide a method for forming an electrode that can be formed.
[0009]
[Means for Solving the Problems]
Claims of the present invention 1, one side and the desired first shape by vapor deposition on the one side plate surface of the light transmitting and the quartz piece having first and second excitation electrodes facing relative to the other side plate surface Forming an excitation electrode ;
Forming a photosensitive resist layer on the other side plate surface of the quartz crystal piece,
Irradiating the light as a photomask to form portions of the first excitation electrode from said one side plate surface of the crystal piece in the resist film,
A step of exposing the another side plate surface of the resist film of the photosensitive portion or the non-photosensitive portion is removed first the crystal piece facing the excitation electrode,
Forming an electrode including the remaining resist layer on the other side plate surface of the quartz piece, by vapor deposition on the entire surface of the other side plate surface,
By removing the resist film and the electrode on the resist film of the other side plate surface of the quartz piece, and forming the second excitation electrode on the other side plate surface,
A method for forming an excitation electrode for a crystal piece, comprising:
[0010]
Then, claim 2 is the one described in claim 1, wherein the resist film is photosensitive portion is cured and the excitation electrodes with respect to the crystal piece, characterized in that the deposited electrode in the non-photosensitive portion of the other side plate surface a forming method, in claim 3 as described in claim 1, wherein the resist film is cured non-photosensitive portion, the crystal piece, characterized in that the formation of the electrodes by vapor deposition on the photosensitive portion of the other side plate surface This is a method of forming an excitation electrode for .
[0011]
Furthermore, claim 4 is in what according to claim 1, wherein the crystal blank is a method of forming the excitation electrodes with respect to the crystal piece, characterized in that it is used for monolithic crystal filter.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to a flowchart shown in FIG. 1 and a side view exaggerated in thickness shown in FIG. 2 by taking as an example a method of forming excitation electrodes for a crystal piece for a monolithic crystal filter. First, “START” is performed at 1, and subsequently, “ the first example vibration electrode 12 is vapor-deposited on one side plate surface” of the crystal piece 11 having optical transparency at 2.
[0013]
The first example vibrating electrode 12 is a metal thin film made of aluminum or silver, for example, and blocks light, whereas the non-formation portion of the first example vibrating electrode is quartz and transmits light. Then, "the entire surface coated with a resist of other side plate surface" of the crystal piece 11 by three. In this case, the formation position of the second example vibration electrode formed on the other side plate surface is determined according to the optical characteristics of the resist.
[0014]
That is, the second excitation electrode on the other side plate surface is formed at a non-photosensitive portion when a resist film that cures a photosensitive portion is used, and a photosensitive portion when a resist film that cures a non-photosensitive portion is used. Formed. Therefore , in the case of a monolithic crystal filter, it is necessary to form the first and second excitation electrodes on the front and back plate surfaces (one side and the other side plate surfaces) so as to face each other accurately. Is used.
[0015]
Then , in 4, “irradiate light from one side plate surface”, the region of the other side plate surface through which the light has passed is set as a hardened resist, and the region of the other side plate surface facing the first example vibration electrode is set as a non-hardened resist. Subsequently, in 5, “removal of non-cured resist” is performed on the other side plate surface facing the first example vibration electrode . Then , 6 “deposits the electrode on the other side plate surface” and 7 performs “removal of the cured resist”. In this case, an electrode is vapor-deposited on the entire surface of the other side plate. Of the metal thin film formed thereby, a portion vapor-deposited on the hardened resist is removed at the same time when the hardened resist is removed.
[0016]
If it does in this way, the resist of the other side plate surface will be exposed by using the first example vibration electrode formed on the one side plate surface of the crystal piece 11 as a mask, and the non-cured portion of the resist film will be removed to deposit the electrode on the other side plate surface. is doing. Then , the cured resist film remaining on the other side plate surface and the electrode thereon are removed. Therefore, the second example vibration electrode having a shape that accurately corresponds to the electrode shape of the first example vibration electrode on the one side plate surface can be formed on the other side plate surface.
[0017]
Furthermore, it is not necessary to store a crystal piece with a minute size in a vapor deposition mask, and the operation can be greatly simplified. Accordingly , the manufacturing cost can be reduced and the first and second excitation electrodes can be accurately formed at desired positions. For example, in the case of a monolithic crystal filter, the electrical characteristics planned at the time of design can be realized. .
[0018]
Thus, according to the above-described embodiment, the first and second excitation electrodes can be formed in a state where they face each other accurately on the front and back plate surfaces of the crystal piece having a small shape and light transmittance, Moreover, processing is easy and high dimensional accuracy can be easily realized.
[0019]
【The invention's effect】
As described above in detail, according to the present invention, the first and second electrodes having the same shape are accurately formed so as to face the front and back plate surfaces ( one side and the other side plate surfaces) of the light transmitting crystal piece. It is possible to provide a method of forming an excitation electrode for a crystal piece that can be used.
[Brief description of the drawings]
FIG. 1 is a flowchart of an embodiment of the present invention.
FIG. 2 is a side view exaggerating the thickness of an embodiment of the present invention.
[Explanation of symbols]
11 .. Crystal piece 12 .. Electrode

Claims (4)

一側及び他側板面に相対面した第1と第2の励振電極を有する光透過性とした水晶片前記一側板面に蒸着によって所望の形状の前記第1励振電極を形成する工程と、
前記水晶片前記他側板面に感光性のレジスト膜を形成する工程と、
前記レジスト膜に前記水晶片前記一側板面から前記第1励振電極の形成部位をフォトマスクとして光を照射する工程と、
前記レジスト膜の感光部分又は非感光部分を除去して前記第1励振電極に対向した前記水晶片の前記他側板面を露出する工程と、
前記水晶片前記他側板面に残ったレジスト膜を含めて、前記他側板面の全面に蒸着によって電極を形成する工程と、
前記水晶片前記他側板面のレジスト膜及び前記レジスト膜上の電極を除去して、前記他側板面に前記第2励振電極を形成する工程と、
からなることを特徴とする水晶片に対する励振電極の形成方法。
Forming a first excitation electrode having a desired shape by vapor deposition on the one side plate surface of the light transmitting and the quartz piece having first and second excitation electrodes facing relative to one side and the other side plate surface,
Forming a photosensitive resist layer on the other side plate surface of the quartz crystal piece,
Irradiating the light as a photomask to form portions of the first excitation electrode from said one side plate surface of the crystal piece in the resist film,
A step of exposing the another side plate surface of the resist film of the photosensitive portion or the non-photosensitive portion is removed first the crystal piece facing the excitation electrode,
Forming an electrode including the remaining resist layer on the other side plate surface of the quartz piece, by vapor deposition on the entire surface of the other side plate surface,
By removing the resist film and the electrode on the resist film of the other side plate surface of the quartz piece, and forming the second excitation electrode on the other side plate surface,
A method of forming an excitation electrode for a crystal piece, comprising :
特許請求の範囲第1項に記載のものにおいて、前記レジスト膜は感光部分が硬化し、前記他側板面の非感光部分に電極を蒸着したことを特徴とする水晶片に対する励振電極の形成方法。In those described in Patent Claim 1, wherein the resist film is photosensitive portion is cured and the method of forming the excitation electrodes with respect to the crystal piece, characterized in that the deposited electrode in the non-photosensitive portion of the other side plate surface. 特許請求の範囲第1項に記載のものにおいて、前記レジスト膜は非感光部分が硬化し、前記他側板面の感光部分に電極を蒸着により形成したことを特徴とする水晶片に対する励振電極の形成方法。In those described in Patent Claim 1, formation of the resist film is cured non-photosensitive portion, the excitation electrode with respect to the crystal piece, characterized in that formed by depositing an electrode on the light-sensitive portion of the other side plate surface Method. 特許請求の範囲第1項に記載のものにおいて、前記水晶片はモノリシック水晶フィルタであることを特徴とする水晶片に対する励振電極の形成方法。In those described in paragraph 1 claims, the method of forming the excitation electrodes with respect to the crystal piece, characterized in that said crystal piece is for monolithic crystal filter.
JP2002082292A 2002-03-25 2002-03-25 Method for forming excitation electrode on quartz piece Expired - Fee Related JP4111731B2 (en)

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