JP2001024470A - Extremely high frequency at cut crystal oscillatory - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an extremely high frequency oscillator for maintaining a Q-value to be large and avoiding deterioration of a capacity ratio by depositing a two sides-opposed electrode to a crystal substrate having a recess on one main surface to specify the shape size of the electrode. SOLUTION: A recess 2 is formed on one main surface of a crystal substrate 1, and electrodes 3a, 3b of different sizes are opposed to each other nearly in the center of the recess 2 so as to match the center part of each. In addition, a reed electrode 4a is pulled out along the X' axis of a coordinate axis from an electrode 3a on a front surface and it is bent at a right angle and extended in the direction of an X-axis to be connected with a pad electrode 5a provided at the end of the substrate 1. A reed electrode 4b is extended along the X axis from an electrode 3b on a rear side surface over a level difference part 6-1 to be connected with a pad electrode 5b provided at the end of the substrate 1. In setting the shape size of the electrode 3a on the front surface to be La×Wa and the shape size of the electrode 3b on the rear side surface to be Lb×Wb, 2La<=Lb<=4La, 2Wa<=Wb<=4Wa.

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ＡＴカット水晶振動
子の構造に関し、特に基本波の超高周波ＡＴカット水晶
振動子の構造に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of an AT-cut quartz resonator, and more particularly to a structure of an ultra-high-frequency AT-cut quartz resonator having a fundamental wave.

【０００２】[0002]

【従来の技術】近年、通信機器の高周波化に伴って、そ
の機器に用いられる圧電デバイスの高周波化が強く要望
されている。図３（ａ）、（ｂ）は超高周波ＡＴカット
水晶振動子の構成を示す斜視図であって、水晶基板11
（以下、基板と称す）の一方の主面に凹陥部12を形成
し、該凹陥部12のほぼ中央に基板11を介して対向する電
極13a、13bを付着すると共に、それぞれの電極からリー
ド電極14a、14bを図３（ａ）、（ｂ）中の左隅に示す座
標軸のＸ軸に沿って基板11の端部まで延在し、その端部
に設けたパッド電極15a、15bと接続する。ここで、主面
が平面である面を表面、凹陥部を有する面を裏面と称す
ことにする。2. Description of the Related Art In recent years, with the increase in the frequency of communication devices, there has been a strong demand for higher frequency piezoelectric devices used in such devices. FIGS. 3A and 3B are perspective views showing the configuration of an ultra-high frequency AT-cut quartz resonator, and show a quartz substrate 11.
A concave portion 12 is formed on one main surface of the substrate (hereinafter, referred to as a substrate). Opposite electrodes 13a and 13b are attached to the substantially central portion of the concave portion 12 with the substrate 11 interposed therebetween. The wires 14a and 14b extend to the end of the substrate 11 along the X axis of the coordinate axes shown at the left corners in FIGS. 3A and 3B, and are connected to the pad electrodes 15a and 15b provided at the ends. Here, the surface having a flat main surface is referred to as a front surface, and the surface having a concave portion is referred to as a back surface.

【０００３】周知のように、ＡＴカット水晶振動子の振
動モードは厚みすべり振動であって、その周波数は水晶
基板の厚さに反比例するため、高周波化を図るには水晶
基板の厚さを薄くする必要がある。しかし、ＡＴカット
水晶基板を通常の平板で作成する場合、基板のマウン
ト、基板の耐衝撃性等の機械的強度を考慮すると、基本
波振動で約５５ＭＨｚ（厚さで約３０μｍ）が上限の周
波数であると考えられる。As is well known, the vibration mode of an AT-cut crystal resonator is thickness-shear vibration, and its frequency is inversely proportional to the thickness of the crystal substrate. There is a need to. However, when an AT-cut quartz substrate is made of a normal flat plate, the upper limit of the frequency is about 55 MHz (about 30 μm in thickness) in the fundamental wave vibration in consideration of the mechanical strength such as the mounting of the board and the impact resistance of the board. It is considered to be.

【０００４】この基本波周波数の上限を上げるために開
発された超高周波ＡＴカット水晶振動子の基板は、フォ
トリソグラフィ技法とエッチングとを用いて製作する。
超高周波ＡＴカット水晶基板の作り方を簡単に説明する
と、厚さ約８０μｍのポリッシュ仕上げしたＡＴカット
水晶基板11の一方の主面の一部をフォトリソグラフィ技
法とエッチングとを用いて凹陥せしめ、該凹陥部12の底
面の厚さを所定の厚さまでエッチングして、超薄肉の振
動部とするとともに、該振動部の周囲を支持する厚肉の
環状囲繞部を一体的に形成する。A substrate of an ultra-high frequency AT-cut crystal resonator developed to raise the upper limit of the fundamental frequency is manufactured by using a photolithography technique and etching.
A method of manufacturing an ultra-high-frequency AT-cut quartz substrate will be briefly described. A part of one main surface of a polished AT-cut quartz substrate 11 having a thickness of about 80 μm is recessed by using a photolithography technique and etching. The thickness of the bottom surface of the portion 12 is etched to a predetermined thickness to form an ultra-thin vibrating portion, and a thick annular surrounding portion supporting the periphery of the vibrating portion is integrally formed.

【０００５】上記の電極13a、13b、リード電極14a、14
b、パッド電極15a、15bをフォトリソグラフィ技術で形
成する場合、凹陥部12の周囲に形成される段差部16−1
〜16−4により電極膜の断線が生ずるおそれがある。そ
こで、図３（ｃ）に示すように裏面全体に電極膜13b'を
付着して、段差部における導通の信頼性向上を図った超
高周波ＡＴカット水晶振動子もある。The above electrodes 13a, 13b and lead electrodes 14a, 14
b, when the pad electrodes 15a and 15b are formed by photolithography, a step 16-1 formed around the recess 12
~ 16-4 may cause disconnection of the electrode film. Therefore, as shown in FIG. 3C, there is an ultra-high-frequency AT-cut crystal resonator in which an electrode film 13b 'is attached to the entire back surface to improve the reliability of conduction at the step.

【０００６】ところで、ＡＴカット振動子の主振動とス
プリアスとなるインハーモニック振動モードとの振る舞
いを、所謂エネルギー閉じ込め理論で論ずるのが一般的
である。インハーモニックモード（スプリアス）を抑圧
したＡＴカット水晶振動子の設計法として、次式がよく
知られている。 Ｌi×√Δ／Ｈ＝α （１） ここでＬi（ｉ=1,2）は部分電極13a、13bのそれぞれ
Ｚ’軸方向、Ｘ軸方向の寸法、Ｈは振動部11の厚さ、Δ
は周波数低下量である。閉じ込め係数αは厚みすべり振
動では2.8となる。周波数低下量Δは振動部のカットオ
フ周波数をｆｓ、電極を付着した場合のカットオフ周波
数をｆｅとすると、次式で表される。 Δ＝（ｆｓ−ｆｅ）／ｆｓ （２）Incidentally, the behavior of the main vibration of the AT-cut vibrator and the inharmonic vibration mode as spurs is generally discussed by the so-called energy confinement theory. The following equation is well known as a method of designing an AT-cut crystal resonator in which the inharmonic mode (spurious) is suppressed. Li × √Δ / H = α (1) where Li (i = 1, 2) is the dimension in the Z′-axis direction and the X-axis direction of each of the partial electrodes 13a and 13b, H is the thickness of the vibrating portion 11, and Δ
Is the frequency drop. The confinement coefficient α is 2.8 for the thickness shear vibration. The frequency decrease amount Δ is represented by the following equation, where fs is the cutoff frequency of the vibrating portion, and fe is the cutoff frequency when the electrode is attached. Δ = (fs−fe) / fs (2)

【０００７】[0007]

【発明が解決しようとする課題】しかしながら、上記の
図３（ａ）、（ｂ）に示した表面、裏面とも部分電極を
用いた超高周波ＡＴカット水晶振動子においては、周波
数低下量Δが表面と裏面の電極（13a、13b）の膜厚h
（質量）で決まるため、エネルギー閉じ込め条件を満た
すには電極膜厚hを薄くしなければならない。その結
果、リード電極14a、14bの幅狭と相まってそのオーミッ
クロスが大きくなるため、Ｑ値が低下し、該振動子を発
振器等に用いる場合に周波数の安定性が劣化するという
問題があった。一方、裏面の電極を全面電極とした振動
子においては周波数低下量Δは表面の電極質量のみで決
まるため、Δは表裏両面が部分電極の場合の２倍程度ま
で厚くすることができるが、リード電極14a、パッド電
極15aと全面電極13b'とが基板11を誘電体として形成す
る不要な静電容量C0'が大きくなり、容量比γ（水晶振
動子のモーショナル容量C1に対する静電容量（C0+C0'）
の比（C0+C0'）／C1）を劣化させるという問題があっ
た。周知のように、水晶振動子を電圧制御発振器に用い
る場合、該発振器の周波数可変範囲は容量比γに逆比例
するため、容量比γは小さいことが望ましい。本発明は
上記問題を解決するためになされたものであって、Ｑ値
を大きく維持すると共に、容量比を劣化させない超高周
波ＡＴカット水晶振動子を提供することを目的とする。However, in the ultrahigh-frequency AT-cut quartz resonator using partial electrodes on both the front and back surfaces shown in FIGS. 3A and 3B, the frequency reduction Δ And the thickness h of the backside electrodes (13a, 13b)
(Mass), the electrode thickness h must be reduced to satisfy the energy confinement condition. As a result, since the ohmic cross becomes large in combination with the narrow width of the lead electrodes 14a and 14b, there is a problem that the Q value is reduced and the frequency stability is deteriorated when the vibrator is used for an oscillator or the like. On the other hand, in the case of the vibrator having the back electrode as the whole electrode, the frequency reduction amount Δ is determined only by the mass of the front electrode, so that Δ can be made about twice as thick as when the front and back surfaces are partial electrodes. The unnecessary capacitance C0 ′ formed by the electrode 14a, the pad electrode 15a, and the full-surface electrode 13b ′ using the substrate 11 as a dielectric becomes large, and the capacitance ratio γ (the capacitance (C0 + with respect to the motional capacitance C1 of the crystal unit) C0 ')
(C0 + C0 ') / C1). As is well known, when a crystal resonator is used for a voltage-controlled oscillator, the frequency variable range of the oscillator is inversely proportional to the capacitance ratio γ, so that the capacitance ratio γ is desirably small. The present invention has been made to solve the above-described problem, and has as its object to provide an ultra-high-frequency AT-cut crystal resonator that maintains a large Q value and does not degrade the capacitance ratio.

【０００８】[0008]

【課題を解決するための手段】上記目的を達成するため
に本発明に係る超高周波ＡＴカット水晶振動子の請求項
１記載の発明は、一方の主面に凹陥部を有する水晶基板
に表裏対向する電極を付着した超高周波ＡＴカット水晶
振動子において、前記電極の一方の形状寸法をＬｂ×Ｗ
ｂとし、他方の電極寸法をＬａ×Ｗａとしたとき、２Ｌ
ａ≦Ｌｂ≦４Ｌａ、２Ｗａ≦Ｗｂ≦４Wａであることを
特徴とする超高周波ＡＴカット水晶振動子である。請求
項２記載の発明は、一方の主面に凹陥部を有する水晶基
板に表裏対向する電極を付着した超高周波ＡＴカット水
晶振動子において、前記表面の電極から引き出すリード
電極はＺ'方向に引き出し、裏面のリード電極はＸ軸方
向に引き出したことを特徴とする請求項１記載の超高周
波ＡＴカット水晶振動子である。According to a first aspect of the present invention, there is provided an ultra-high-frequency AT-cut quartz resonator according to the present invention, wherein a quartz substrate having a concave portion on one main surface is opposed to a quartz substrate. In an ultra-high frequency AT-cut quartz resonator to which an electrode to be attached is attached, one dimension of the electrode is Lb × W
b and the other electrode dimension is La × Wa, 2L
An ultra-high-frequency AT-cut crystal resonator, wherein a ≦ Lb ≦ 4La and 2Wa ≦ Wb ≦ 4Wa. According to a second aspect of the present invention, in a super-high frequency AT-cut quartz resonator in which electrodes facing each other are attached to a quartz substrate having a concave portion on one main surface, a lead electrode pulled out from the electrode on the front surface is drawn in the Z ′ direction. 2. The ultrahigh-frequency AT-cut crystal resonator according to claim 1, wherein the lead electrode on the back surface is drawn in the X-axis direction.

【０００９】[0009]

【発明の実施の形態】以下本発明を図面に示した実施の
形態に基づいて詳細に説明する。図１（ａ）、（ｂ）は
本発明に係る超高周波ＡＴカット水晶振動子の構成を示
す斜視図であって、水晶基板1の一方の主面に凹陥部2を
形成し、該凹陥部2のほぼ中央に大きさの異なる電極3
a、3bをそれぞれの中心部が一致するように対向させる
と共に、表面の電極3aからは図の左隅に示した座標軸の
Z'軸に沿ってリード電極4aを引き出し、それを直角に曲
げてX軸方向に延在し、基板1の端部に設けたパッド電極
5aと接続する。さらに、裏面の電極3bからX軸に沿って
リード電極4bを段差部6−1を越えて延在し、基板1の端
部に設けたパッド電極5bと接続する。本発明の特徴は表
面の電極3a（Ｘ軸、Ｚ'軸方向の寸法をそれぞれLa、W
a）と裏面の電極3b（Ｘ軸、Ｚ'軸方向の寸法をそれぞれ
Lb、Wb）の大きさを異ならせたことと、表面のリード電
極4aをZ'方向に引き出し、裏面のリード4bをX軸方向に
引き出して、リード電極の長さを短くすると共に、リー
ド電極同士が互いに交叉しないようにしたことである。DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail based on an embodiment shown in the drawings. FIGS. 1A and 1B are perspective views showing the configuration of an ultra-high frequency AT-cut crystal resonator according to the present invention, in which a concave portion 2 is formed on one main surface of a quartz substrate 1 and the concave portion 2 is formed. Electrodes 3 of different sizes almost in the center of 2
a and 3b are opposed to each other so that their respective center portions coincide with each other, and the coordinate axes shown in the left corner of the figure are viewed from the surface electrode 3a.
A lead electrode 4a is pulled out along the Z 'axis, bent at a right angle, extended in the X axis direction, and provided with a pad electrode provided at an end of the substrate 1.
Connect with 5a. Further, a lead electrode 4b extends from the electrode 3b on the back surface along the X axis beyond the step 6-1 and is connected to a pad electrode 5b provided at an end of the substrate 1. The feature of the present invention is that the dimensions of the surface electrode 3a (X-axis and Z'-axis directions are La and W, respectively).
a) and backside electrode 3b (dimensions in X-axis and Z'-axis directions
Lb, Wb), the lead electrode 4a on the front surface is pulled out in the Z 'direction, the lead 4b on the back surface is pulled out in the X-axis direction, and the length of the lead electrode is shortened. That is, they do not cross each other.

【００１０】図１のように表面の電極3aと裏面の電極3b
との互いの中心を一致させると共に、電極3aと電極3bの
形状寸法を異ならせると、振動モードの変位分布を表面
の電極3aの大きさ（La、Wa）とその電極膜厚h、即ち質
量のみに依存させることが後述するように可能となる。As shown in FIG. 1, the front electrode 3a and the back electrode 3b
When the centers of the electrodes 3a and 3b are made different from each other and the shapes and dimensions of the electrodes 3a and 3b are made different from each other, the displacement distribution of the vibration mode is represented by the size (La, Wa) of the electrode 3a on the surface and its electrode thickness h, It is possible to rely only on this as described later.

【００１１】即ち、裏面の電極が全面電極である場合、
所望の周波数が設定されると、それに応じて振動部の厚
さHが決まり、エネルギー閉じ込めの式（１）より、ス
プリアスを抑圧するのに最適な電極3aの形状寸法（La、
Wa）とその電極膜厚h（周波数低下量Δ）が求まる。こ
の状態から、表面の電極3aの中心に対応する裏面の全面
電極（電極膜厚h'）の中心からＸ軸、Ｚ'軸方向とも両
側に対称に少しずつ全面電極を除去しながら、振動モー
ドの変位分布の変化をシミュレーションにより求める。
裏面の電極3bの寸法（Lb、Wb）がLb＜２・La及びWb＜２
・Waとなると、変位分布が元の状態、即ち裏面電極が全
面電極であったときの変位分布から少し変化をはじめ
る。これはエネルギー閉じ込め現象が裏面の電極の寸法
とその電極膜厚h'の影響を受けることを示している。裏
面の電極3bをさらに小さくしていくと変位分布は元の分
布から変化し、主振動以外にスプリアスモードの振幅も
大きくなる。さらに裏面の電極を小さくして表裏の電極
3a、3bが全く等しくなると、電極膜厚は（h+h'）であ
り、エネルギー閉じ込め理論より求まる電極膜厚の最適
値hに対し（h+h'）／hとなり、約２倍の膜厚となり、ス
プリアスの数も多くなりその振幅も大きくなる。That is, when the electrode on the back surface is a full surface electrode,
When the desired frequency is set, the thickness H of the vibrating part is determined according to the desired frequency, and from the energy trapping equation (1), the optimal shape (La,
Wa) and its electrode thickness h (frequency reduction amount Δ) are obtained. From this state, while removing the whole electrode little by little symmetrically on both sides in the X-axis and Z′-axis directions from the center of the whole surface electrode (electrode thickness h ′) corresponding to the center of the front surface electrode 3a, The change in the displacement distribution is determined by simulation.
The dimensions (Lb, Wb) of the back electrode 3b are Lb <2 · La and Wb <2
When Wa is reached, the displacement distribution slightly changes from the original state, that is, the displacement distribution when the back surface electrode is the entire surface electrode. This indicates that the energy confinement phenomenon is affected by the size of the back electrode and the thickness h ′ of the electrode. When the electrode 3b on the back surface is further reduced, the displacement distribution changes from the original distribution, and the amplitude of the spurious mode as well as the main vibration increases. Further reduce the size of the electrode on the back and make the electrode on the front and back
When 3a and 3b are completely equal, the electrode thickness is (h + h '), which is (h + h') / h with respect to the optimum value h of the electrode thickness obtained from the energy confinement theory, and the film thickness is about twice as large. As the thickness increases, the number of spurious components increases and the amplitude thereof also increases.

【００１２】本発明は全面電極の特徴、即ち表面の電極
3aの大きさとその電極膜厚hのみにエネルギー閉じ込め
が依存するという特徴を活かすことにある。この場合、
裏面の電極の膜厚h'は基板1の周波数のみを低下させる
ように作用するだけである。裏面の電極の形状寸法（L
b、Wb）を上述した特徴が活かせる最小の形状寸法まで
小さくすることにより、表面のリード電極4aと裏面の電
極3bの重なる面積を最小にすることにより、不要な静電
容量C0'を小さくし、超高周波ＡＴカット水晶振動子の
容量比γを小さくすることが可能となる。The present invention is characterized by the characteristics of the entire surface electrode, that is, the surface electrode.
The advantage is that the energy confinement depends only on the size of 3a and its electrode thickness h. in this case,
The thickness h ′ of the back electrode only acts to reduce only the frequency of the substrate 1. Back electrode shape (L
b, Wb) is reduced to the minimum shape and dimension that can take advantage of the above-described features, thereby minimizing the overlapping area between the lead electrode 4a on the front surface and the electrode 3b on the back surface, thereby reducing unnecessary capacitance C0 ′. However, it is possible to reduce the capacitance ratio γ of the ultrahigh frequency AT-cut crystal resonator.

【００１３】図２は超高周波ＡＴカット水晶振動子用の
基板1であり、（ａ）は平面図、（ｂ）はP−Pにおける
断面図を示したものである。図２（ａ）はＡＴカット水
晶基板にＸ軸方向に対して台形の凹陥部を形成した例で
あるが、結晶軸方向により段差部6−1〜6−4の傾斜がそ
れぞれ異なり、特に同図（ｂ）の断面図に示すように段
差部6−2はなだらかな傾斜ではなく、楔状に逆方向に折
り曲がった断面となっている。このような段差部6−2に
蒸着等の手段でリード電極を付着しても電極膜の導通が
とれないのは明らかである。従って、段差部6−1かある
いは段差部6−4を経て引き出すのがよいが、リード電極
の長さを最短にするには段差部6−1を経て引き出すのが
最適である。2A and 2B show a substrate 1 for an ultra-high-frequency AT-cut quartz resonator, wherein FIG. 2A is a plan view and FIG. 2B is a cross-sectional view taken along line PP. FIG. 2A shows an example in which a trapezoidal recess is formed in the AT-cut quartz substrate in the X-axis direction. The inclinations of the steps 6-1 to 6-4 are different depending on the crystal axis direction. As shown in the cross-sectional view of FIG. 13B, the step portion 6-2 has a cross section bent in the opposite direction in a wedge shape instead of a gentle inclination. Obviously, even if a lead electrode is attached to such a step portion 6-2 by means such as vapor deposition, conduction of the electrode film cannot be obtained. Accordingly, it is preferable that the lead electrode is drawn through the step portion 6-1 or the step portion 6-4, but it is optimal to draw the lead electrode through the step portion 6-1 in order to minimize the length of the lead electrode.

【００１４】本発明は以上説明したように、表面の電極
３ａの形状寸法（La、Wa）とその電極膜厚hのみで超高
周波ＡＴカット水晶振動子の特性が決まるように、対向
した裏面の電極３ｂの形状寸法（Lb、Wb）を設定すると
共に、電極3aからのリード電極4aはZ'軸方向に引き出
し、電極3bからのリード電極4bはＸ軸方向に引き出して
いる。その結果、リード電極4a、4bの長さを短くし、導
通の信頼性を高めると共に、リード電極4aと電極3bとで
形成する不要な静電容量C0'を極力小さくすることが可
能となり、超高周波ＡＴカット水晶振動子のQ値を大き
く維持したまま、容量比を小さくできるようになった。As described above, according to the present invention, the characteristics of the ultra-high-frequency AT-cut quartz resonator are determined only by the shape and dimensions (La, Wa) of the electrode 3a on the front surface and the electrode thickness h thereof. The shape and dimensions (Lb, Wb) of the electrode 3b are set, the lead electrode 4a from the electrode 3a is drawn out in the Z'-axis direction, and the lead electrode 4b from the electrode 3b is drawn out in the X-axis direction. As a result, it is possible to shorten the lengths of the lead electrodes 4a and 4b, improve the reliability of conduction, and minimize unnecessary capacitance C0 'formed by the lead electrodes 4a and the electrodes 3b. The capacitance ratio can be reduced while maintaining a high Q value of the high-frequency AT-cut quartz resonator.

【００１５】[0015]

【発明の効果】本発明は、以上説明したように構成した
ので、高Qであると共に、容量比の小さな超高周波ＡＴ
カット水晶振動子が得られるようになり、該振動子を高
周波の電圧制御発振器等に用いれば可変範囲の広く、且
つ周波数の安定した発振器が実現するという優れた効果
を奏す。According to the present invention, as described above, an ultra-high frequency AT having a high Q and a small capacity ratio is provided.
A cut crystal resonator can be obtained, and when this resonator is used for a high-frequency voltage-controlled oscillator, an excellent effect of realizing an oscillator having a wide variable range and a stable frequency is achieved.

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

【図１】（ａ）、（ｂ）は本発明に係る超高周波ＡＴカ
ット水晶振動子の表面及び裏面の斜視図である。FIGS. 1A and 1B are perspective views of a front surface and a back surface of an ultra-high frequency AT-cut crystal resonator according to the present invention.

【図２】（ａ）は超高周波ＡＴカット水晶振動子用の水
晶基板の平面図、（ｂ）は断面図である。FIG. 2A is a plan view of a quartz substrate for an ultra-high frequency AT-cut quartz resonator, and FIG. 2B is a cross-sectional view.

【図３】従来の超高周波ＡＴカット水晶振動子の斜視図
であり、（ａ）は表面の斜視図、（ｂ）は裏面の斜視
図、（ｃ）は全面電極を付着した場合の斜視図である。3A and 3B are perspective views of a conventional ultra-high-frequency AT-cut crystal resonator, wherein FIG. 3A is a front perspective view, FIG. 3B is a rear perspective view, and FIG. It is.

【符号の説明】[Explanation of symbols]

１・・基板 ２・・凹陥部（振動部） ３ａ、３ｂ・・電極 ４ａ、４ｂ・・リード電極 ５ａ、５ｂ・・パッド電極 6−1、6−2、6−3、6−4・・段差部 Ｌａ、Ｌｂ、Ｗａ、Ｗｂ・・電極の形状寸法 1. Substrate 2. Depressed part (vibrating part) 3a, 3b .. Electrode 4a, 4b .. Lead electrode 5a, 5b .. Pad electrode 6-1, 6-2, 6-3, 6-4 .. Steps La, Lb, Wa, Wb: Shapes and dimensions of electrodes

Claims (2)

【特許請求の範囲】[Claims] 【請求項１】 一方の主面に凹陥部を有する水晶基板に
表裏対向する電極を付着した超高周波ＡＴカット水晶振
動子において、前記電極の一方の形状寸法をＬｂ×Ｗｂ
とし、他方の電極寸法をＬａ×Ｗａとしたとき、２Ｌａ
≦Ｌｂ≦４Ｌａ、２Ｗａ≦Ｗｂ≦４Wａであることを特
徴とする超高周波ＡＴカット水晶振動子。1. An ultra-high-frequency AT-cut quartz resonator in which electrodes facing each other are attached to a quartz substrate having a recess on one main surface, and one of the electrodes has a shape of Lb × Wb.
And when the other electrode dimension is La × Wa, 2La
≦ Lb ≦ 4La, 2Wa ≦ Wb ≦ 4Wa, an ultra-high frequency AT-cut crystal resonator. 【請求項２】 一方の主面に凹陥部を有する水晶基板に
表裏対向する電極を付着した超高周波ＡＴカット水晶振
動子において、前記表面の電極から引き出すリード電極
はＺ'方向に引き出し、裏面のリード電極はＸ軸方向に
引き出したことを特徴とする請求項１記載の超高周波Ａ
Ｔカット水晶振動子。2. In an ultra-high-frequency AT-cut quartz resonator in which electrodes facing each other are attached to a quartz substrate having a concave portion on one main surface, a lead electrode drawn from the electrode on the front surface is drawn in the Z ′ direction, 2. The ultrahigh frequency A according to claim 1, wherein the lead electrode is drawn in the X-axis direction.
T-cut crystal oscillator.