JP4965962B2 - Micromechanical resonator - Google Patents
Micromechanical resonator Download PDFInfo
- Publication number
- JP4965962B2 JP4965962B2 JP2006279356A JP2006279356A JP4965962B2 JP 4965962 B2 JP4965962 B2 JP 4965962B2 JP 2006279356 A JP2006279356 A JP 2006279356A JP 2006279356 A JP2006279356 A JP 2006279356A JP 4965962 B2 JP4965962 B2 JP 4965962B2
- Authority
- JP
- Japan
- Prior art keywords
- resonant beam
- electrode
- resonator
- gap
- resonant
- 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
Links
- 239000000758 substrate Substances 0.000 claims description 33
- 238000006073 displacement reaction Methods 0.000 claims description 8
- 230000003068 static effect Effects 0.000 claims description 3
- 229910052710 silicon Inorganic materials 0.000 description 13
- 239000010703 silicon Substances 0.000 description 13
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 9
- 229910052782 aluminium Inorganic materials 0.000 description 9
- 239000004020 conductor Substances 0.000 description 9
- 230000010355 oscillation Effects 0.000 description 8
- 238000004891 communication Methods 0.000 description 5
- 239000011521 glass Substances 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000004065 semiconductor Substances 0.000 description 2
- 238000004364 calculation method Methods 0.000 description 1
- 238000005094 computer simulation Methods 0.000 description 1
- 229910003460 diamond Inorganic materials 0.000 description 1
- 239000010432 diamond Substances 0.000 description 1
- 238000007667 floating Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H9/00—Networks comprising electromechanical or electro-acoustic elements; Electromechanical resonators
- H03H9/24—Constructional features of resonators of material which is not piezoelectric, electrostrictive, or magnetostrictive
- H03H9/2405—Constructional features of resonators of material which is not piezoelectric, electrostrictive, or magnetostrictive of microelectro-mechanical resonators
- H03H9/2447—Beam resonators
- H03H9/2463—Clamped-clamped beam resonators
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H9/00—Networks comprising electromechanical or electro-acoustic elements; Electromechanical resonators
- H03H9/02—Details
- H03H9/02244—Details of microelectro-mechanical resonators
- H03H9/02259—Driving or detection means
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H9/00—Networks comprising electromechanical or electro-acoustic elements; Electromechanical resonators
- H03H9/02—Details
- H03H9/02244—Details of microelectro-mechanical resonators
- H03H2009/02488—Vibration modes
- H03H2009/02496—Horizontal, i.e. parallel to the substrate plane
Landscapes
- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Micromachines (AREA)
- Piezo-Electric Or Mechanical Vibrators, Or Delay Or Filter Circuits (AREA)
Description
本発明は、入力された高周波信号を機械的な信号に変換した後に再び高周波信号に変換して出力する共振器に関し、特に、半導体分野における微細加工技術を利用して作製されるマイクロメカニカル共振器に関するものである。 The present invention relates to a resonator that converts an input high-frequency signal into a mechanical signal, and then converts it back into a high-frequency signal and outputs the same, and more particularly, a micromechanical resonator manufactured using a microfabrication technique in the semiconductor field. It is about.
近年、半導体分野における微細加工技術を利用して、微細な機械構造を電子回路と一体化して形成する、所謂マイクロエレクトロメカニカルシステム(MEMS)技術が開発されており、フィルターや共振器への応用が検討されている。 In recent years, so-called microelectromechanical system (MEMS) technology has been developed that uses microfabrication technology in the semiconductor field to form a fine mechanical structure integrated with an electronic circuit, and has been applied to filters and resonators. It is being considered.
図15は、MEMS技術を用いた従来のマイクロメカニカル共振器を表わしている(非特許文献1)。該マイクロメカニカル共振器は、図示の如く基板(96)上に共振子(90)を具え、該共振子(90)は、角柱状の共振ビーム(92)と、該共振ビーム(92)の両端部を支持すべき4本の角柱状の支持ビーム(91)〜(91)とから構成されており、各支持ビーム(91)の基端部はそれぞれアンカー(93)によって基板(96)上に固定されている。これによって、共振子(90)は、基板(96)の表面から僅かに浮上した位置に保持されている。 FIG. 15 shows a conventional micromechanical resonator using MEMS technology (Non-Patent Document 1). The micromechanical resonator includes a resonator (90) on a substrate (96) as illustrated, and the resonator (90) includes a prismatic resonance beam (92) and both ends of the resonance beam (92). It is composed of four prismatic support beams (91) to (91) to be supported, and the base ends of the support beams (91) are respectively mounted on the substrate (96) by anchors (93). It is fixed. Thus, the resonator (90) is held at a position slightly floating from the surface of the substrate (96).
又、共振子(90)の共振ビーム(92)の両側には、共振ビーム(92)の中央部を挟んで入力電極(94)と出力電極(95)が配備され、共振ビーム(92)と両電極(94)95)との間に所定のギャップ部Gが形成されている。
そして、入力電極(94)には高周波電源(6)が接続されると共に、1つのアンカー(93)には主電圧電源(7)が接続されている。
In addition, on both sides of the resonant beam (92) of the resonator (90), an input electrode (94) and an output electrode (95) are disposed across the center of the resonant beam (92), and the resonant beam (92) and A predetermined gap G is formed between the two electrodes (94) 95).
A high frequency power source (6) is connected to the input electrode (94), and a main voltage power source (7) is connected to one anchor (93).
アンカー(93)を介して共振子(90)に直流電圧Vpを印加した状態で、入力電極(94)に高周波信号Viを入力すると、入力電極(94)と共振ビーム(92)との間にギャップ部Gを介して交番静電気力が発生し、該静電気力によって共振子(90)が基板(96)の表面と平行な面内で振動する。この共振子(90)の振動により、共振ビーム(92)と両電極(95)(94)との間に形成される静電容量が変化し、該静電容量の変化が出力電極(95)から高周波信号Ioとして出力される。 When a high frequency signal Vi is input to the input electrode (94) in a state where the DC voltage Vp is applied to the resonator (90) through the anchor (93), the input electrode (94) and the resonant beam (92) are placed between them. An alternating electrostatic force is generated through the gap portion G, and the resonator (90) vibrates in a plane parallel to the surface of the substrate (96) by the electrostatic force. Due to the vibration of the resonator (90), the capacitance formed between the resonant beam (92) and both electrodes (95) (94) changes, and the change in the capacitance is caused by the change in the output electrode (95). Is output as a high-frequency signal Io.
又、図16は、従来の他のマイクロメカニカル共振器を表わしている(非特許文献2、特許文献1)。該マイクロメカニカル共振器は、基板(107)上に平板状の共振子(100)を具え、該共振子(100)は、両端部と中央部の3カ所に支持部(103)を有すると共に、隣接する2つの支持部(103)(103)間に共振ビーム(102)を有している。各支持部(103)には支持ビーム(101)が突設され、各支持ビーム(101)の基端部はそれぞれアンカー(104)によって基板(107)に固定されている。これによって、共振子(100)は、基板(107)の表面から僅かに浮上した位置に保持されている。
FIG. 16 shows another conventional micro mechanical resonator (Non-patent
又、基板(107)上には、共振子(100)の2つの共振ビーム(102)(102)との間に、入力電極(106)と出力電極(105)が配備され、一方の共振ビーム(102)と入力電極(106)の間、並びに他方の共振ビーム(102)と出力電極(105)との間に、所定のギャップ部が形成されている。
そして、入力電極(106)には高周波電源(6)が接続されると共に、1つのアンカー(104)には主電圧電源(7)が接続されている。
On the substrate (107), an input electrode (106) and an output electrode (105) are provided between the two resonant beams (102) and (102) of the resonator (100). A predetermined gap is formed between (102) and the input electrode (106) and between the other resonant beam (102) and the output electrode (105).
A high frequency power source (6) is connected to the input electrode (106), and a main voltage power source (7) is connected to one anchor (104).
アンカー(104)を介して共振子(100)に直流電圧Vpを印加した状態で、入力電極(106)に高周波信号Viを入力すると、入力電極(106)と共振ビーム(102)との間にギャップ部を介して交番静電気力が発生し、該静電気力によって共振子(100)が基板(107)の表面と垂直な面内で振動する。この共振子(100)の振動により、共振子(100)と両電極(106)(105)との間に形成される静電容量が変化し、該静電容量の変化が出力電極(105)から高周波信号Ioとして出力される。 When a high frequency signal Vi is input to the input electrode (106) in a state where the DC voltage Vp is applied to the resonator (100) via the anchor (104), the input electrode (106) and the resonant beam (102) are interposed between them. An alternating electrostatic force is generated through the gap, and the resonator (100) vibrates in a plane perpendicular to the surface of the substrate (107) by the electrostatic force. Due to the vibration of the resonator (100), the capacitance formed between the resonator (100) and both electrodes (106) (105) changes, and the change in the capacitance is the output electrode (105). Is output as a high-frequency signal Io.
上述の如きマイクロメカニカル共振器においては、図17(a)に示す1次の共振モードの他、同図(b)に示す2次の共振モードや同図(c)に示す3次の共振モード等の高次の共振モードが混在して発生するが、特にマイクロメカニカル共振器をGHz帯で動作する高周波無線通信機器に応用する場合、製造時の加工を容易にするため、共振器のサイズを大きく出来る、高次の共振モードを利用する必要がある。しかしながら、図18に示す如く、1次の共振モードの強度が最も高く、3次の共振モード、5次の共振モードと、高次になるほど強度が低くなるため、応用が進んでいないのが実状である。 In the micromechanical resonator as described above, in addition to the primary resonance mode shown in FIG. 17A, the secondary resonance mode shown in FIG. 17B and the tertiary resonance mode shown in FIG. However, when micromechanical resonators are applied to high-frequency wireless communication devices operating in the GHz band, the size of the resonators should be reduced in order to facilitate processing during manufacturing. It is necessary to use a higher-order resonance mode that can be increased. However, as shown in FIG. 18, the first-order resonance mode has the highest intensity, the third-order resonance mode, the fifth-order resonance mode, and the higher the order, the lower the intensity. It is.
そこで本発明の目的は、1次の共振モードの振動を抑えて高次の共振モードの振動を増大させることが可能なマイクロメカニカル共振器を提供することである。 Accordingly, an object of the present invention is to provide a micromechanical resonator capable of suppressing the vibration of the first-order resonance mode and increasing the vibration of the higher-order resonance mode.
本発明に係るマイクロメカニカル共振器は、基板(9)上に両端部が支持された共振ビーム(52)と、該共振ビーム(52)を挟んで両側に配置された2つの電極(1)(2)とを具え、共振ビーム(52)の両端部間にて、一方の電極(1)と共振ビーム(52)とが互いに対向して、1或いは複数のギャップ部が形成されると共に、他方の電極(2)と共振ビーム(52)とが互いに対向して、1或いは複数のギャップ部が形成され、高周波信号の入力により何れか一方若しくは両方の電極(1)(2)と共振ビーム(52)との間に交番静電気力を発生させて共振ビーム(52)に振動を与え、何れか一方若しくは両方の電極(1)(2)と共振ビーム(52)との間の静電容量の変化を高周波信号として出力するものであって、共振ビーム(52)に対して各ギャップ部を介して作用する静電気力の変動幅が、共振ビーム(52)の中央部近傍のギャップ部で最も小さく且つ両端部近傍のギャップ部で最も大きくなる様に設定されている。 The micromechanical resonator according to the present invention includes a resonant beam (52) whose both ends are supported on a substrate (9), and two electrodes (1) (1) disposed on both sides of the resonant beam (52). 2), one electrode (1) and the resonant beam (52) face each other between both ends of the resonant beam (52) to form one or a plurality of gaps, and the other The electrode (2) and the resonant beam (52) are opposed to each other to form one or a plurality of gaps, and one or both of the electrodes (1) (2) and the resonant beam ( 52) to generate an alternating electrostatic force between them and vibrate the resonant beam (52) so that the capacitance between one or both of the electrodes (1), (2) and the resonant beam (52) The change is output as a high-frequency signal, and the fluctuation range of the electrostatic force acting on the resonant beam (52) through each gap portion is Are smallest and most larger set as in the gap portion near both ends in the gap portion of the vicinity of the central portion of the vibration beam (52).
上記本発明のマイクロメカニカル共振器においては、共振ビーム(52)に対して各ギャップ部を介して作用する静電気力の変動幅が、共振ビーム(52)の中央部近傍のギャップ部で最も小さく且つ両端部近傍のギャップ部で最も大きくなる様に設定されているので、共振ビーム(52)に発生する高次共振モードの振動波形は、該波形に含まれる複数のピーク値が互いに等しくなる理想的なものに近づき、その結果、1次の共振モードの振動が抑えられて高次の共振モードの振動が増大することになる。 In the micromechanical resonator of the present invention, the fluctuation range of the electrostatic force acting on the resonance beam (52) through each gap portion is the smallest in the gap portion near the center portion of the resonance beam (52) and Since it is set to be the largest in the gap near both ends, the vibration waveform of the higher-order resonance mode generated in the resonant beam (52) is ideal in that the multiple peak values included in the waveform are equal to each other. As a result, the vibration in the first-order resonance mode is suppressed and the vibration in the higher-order resonance mode is increased.
共振ビーム(52)の両端部間に形成されている各ギャップ部を介して発生する静電気力の変動幅が、共振ビーム(52)の中央部近傍のギャップ部で最も小さく且つ両端部近傍のギャップ部で最も大きくなる様に設定するための具体的な構成としては、例えば次の構成を採用することが出来る。 The fluctuation range of the electrostatic force generated through each gap formed between both ends of the resonant beam (52) is the smallest in the gap near the center of the resonant beam (52) and the gap near both ends. For example, the following configuration can be adopted as a specific configuration for setting the maximum value in each section.
1.一方の電極(1)は共振ビーム(52)の中央部近傍にギャップ部を形成すると共に、他方の電極(2)は共振ビーム(52)の両端部近傍にギャップ部を形成するものであって、前記他方の電極(2)には、該電極(2)に一定のバイアス電圧を印加するためのバイアス電圧源が接続されている構成、
2.共振ビーム(52)の両端部間に形成されている各ギャップ部のギャップ長が、共振ビーム(52)の中央部近傍のギャップ部で最も大きく且つ両端部近傍のギャップ部で最も小さくなる様に設定されている構成、
3.共振ビーム(52)の両端部間に形成されている各ギャップ部の幅が、共振ビーム(52)の中央部近傍のギャップ部で最も小さく且つ両端部近傍のギャップ部で最も大きくなる様に設定されている構成。
1. One electrode (1) forms a gap near the center of the resonant beam (52), and the other electrode (2) forms a gap near both ends of the resonant beam (52). A configuration in which a bias voltage source for applying a constant bias voltage to the electrode (2) is connected to the other electrode (2);
2. The gap length of each gap formed between both ends of the resonant beam (52) is the largest in the gap near the center of the resonant beam (52) and the smallest in the gap near both ends. Configured configuration,
3. The width of each gap formed between both ends of the resonant beam (52) is set to be the smallest in the gap near the center of the resonant beam (52) and the largest in the gap near both ends. Configuration.
又、共振ビーム(52)の各ギャップ部に面する領域に作用させるべき交番静電気力の大きさを決定する具体的な方法としては、次の方法を採用することが出来る。
共振ビーム(52)の各領域に一定の静電気力を作用させることによって各領域に生じる共振ビーム(52)の静的変位量を求め、これらの領域における静的変位量が領域間で均等となる様、各領域での静電気力の領域間比率を決定する。そして、その静電気力の領域間比率と一致若しくは略一致する様に、共振ビーム(52)の各ギャップ部に面する領域に作用させるべき交番静電気力の領域間の比率を設定する。
Further, the following method can be adopted as a specific method for determining the magnitude of the alternating electrostatic force to be applied to the region facing each gap portion of the resonant beam (52).
The static displacement amount of the resonance beam (52) generated in each region is obtained by applying a constant electrostatic force to each region of the resonance beam (52), and the static displacement amount in these regions becomes uniform between the regions. In the same way, the ratio between the areas of the electrostatic force in each area is determined. Then, the ratio between the areas of the alternating electrostatic force to be applied to the areas facing the gap portions of the resonant beam (52) is set so as to match or substantially match the ratio between the areas of the electrostatic force.
これによって、共振ビーム(52)に対して各ギャップ部を介して作用する静電気力の変動幅が、共振ビーム(52)の中央部近傍のギャップ部で最も小さく且つ両端部近傍のギャップ部で最も大きくなって、共振ビーム(52)に発生する高次共振モードの振動波形が理想的なものとなる。 As a result, the fluctuation range of the electrostatic force acting on the resonant beam (52) through each gap is the smallest in the gap near the center of the resonant beam (52) and the smallest in the gap near both ends. As a result, the vibration waveform of the higher-order resonance mode generated in the resonance beam (52) becomes ideal.
具体的構成において、共振ビーム(52)には、振動の節となる複数の領域にそれぞれ、他の領域よりも断面積の小さなくびれ部(54)が凹設されている。
該具体的構成によれば、共振ビーム(52)が高次共振モードで振動するとき、共振ビーム(52)は断面積の小さなくびれ部(54)にて容易に屈曲するので、共振ビーム(52)には理想的な波形の振動が発生し易くなる。
In a specific configuration, the resonance beam (52) is provided with a constricted portion (54) having a smaller cross-sectional area than other regions in a plurality of regions serving as vibration nodes.
According to this specific configuration, when the resonant beam (52) vibrates in the higher-order resonance mode, the resonant beam (52) is easily bent at the constricted portion (54) having a small cross-sectional area. ) Is likely to generate ideal waveform vibration.
本発明に係るマイクロメカニカル共振器によれば、1次の共振モードの振動よりも高次の共振モードの振動が増大するので、該高次共振モードを利用することにより、従来よりも高い周波数帯域で動作する高周波無線通信機器を容易に構成することが出来る。 According to the micromechanical resonator according to the present invention, the vibration of the higher order resonance mode is increased than the vibration of the first order resonance mode. It is possible to easily configure a high-frequency wireless communication device that operates in
以下、本発明の実施の形態につき、図面に沿って具体的に説明する。
基本構成
図1は、本発明に係るマイクロメカニカル共振器の基本的な構成を表わしている。該マイクロメカニカル共振器においては、基板(9)上に共振ビーム(52)が配備され、該共振ビーム(52)の両端部はそれぞれアンカー(3)により基板(9)に固定されており、これによって、共振ビーム(52)は基板(9)の表面から僅かに浮上した位置に保持されている。
斯くして、共振ビーム(52)は、両アンカー(3)(3)が支持部(50)(50)となって、基板(9)の表面と平行な面内で振動が可能である。
Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings.
Basic Configuration FIG. 1 shows a basic configuration of a micromechanical resonator according to the present invention. In the micromechanical resonator, a resonant beam (52) is provided on a substrate (9), and both ends of the resonant beam (52) are fixed to the substrate (9) by anchors (3). Thus, the resonant beam (52) is held at a position slightly lifted from the surface of the substrate (9).
Thus, the resonant beam (52) can vibrate in a plane parallel to the surface of the substrate (9), with both anchors (3) and (3) serving as support portions (50) and (50).
共振ビーム(52)には、その両端部を含む4つの領域に、他の領域よりも断面積の小さなくびれ部(54)〜(54)が凹設されており、これによって形成される3つの非くびれ部(53)(53)(53)を挟んで両側には、1つの電極突出部(10)を有する第1の電極と2つの電極突出部(20)(20)を有する第2の電極とが対向配備され、3つの電極突出部(10)(20)(20)と3つの非くびれ部(53)(53)(53)との間にはそれぞれ所定のギャップ部が形成されている。
図1の例は3次共振モードを得るための構成を示し、共振ビーム(52)における3次共振モードの腹の部分に対応して電極突出部(10)(10)(10)が配置され、節の部分に対応してくびれ部(54)〜(54)が形成される。
In the resonant beam (52), constricted portions (54) to (54) having a smaller cross-sectional area than the other regions are recessed in four regions including both ends thereof. A first electrode having one electrode protrusion (10) and a second electrode having two electrode protrusions (20) (20) on both sides of the non-constricted part (53) (53) (53). The electrodes are arranged opposite to each other, and predetermined gap portions are formed between the three electrode protrusions (10), (20), and (20) and the three non-constricted portions (53), (53), and (53), respectively. Yes.
The example of FIG. 1 shows a configuration for obtaining the third-order resonance mode, and electrode protrusions (10), (10), (10) are arranged corresponding to the antinode portions of the third-order resonance mode in the resonance beam (52). The constricted portions (54) to (54) are formed corresponding to the node portions.
そして、2つの電極には高周波電源(図示省略)が接続されると共に、一方のアンカー(3)には主電圧電源(図示省略)が接続されて、他方のアンカー(3)から高周波信号が出力される。
この場合、一方のアンカー(3)を介して共振ビーム(52)に直流電圧を印加した状態で、2つの電極に高周波信号を入力すると、共振ビーム(52)と両電極の間にギャップ部を介して交番静電気力が発生し、該静電気力によって共振ビーム(52)が基板(9)の表面と平行な面内で振動する。この共振ビーム(52)の振動により、共振ビーム(52)と両電極の間の静電容量が変化し、該静電容量の変化が他方のアンカー(3)から高周波信号として出力される。
A high-frequency power source (not shown) is connected to the two electrodes, a main voltage power source (not shown) is connected to one anchor (3), and a high-frequency signal is output from the other anchor (3). Is done.
In this case, when a high frequency signal is input to the two electrodes with a DC voltage applied to the resonant beam (52) via one anchor (3), a gap is formed between the resonant beam (52) and both electrodes. Then, an alternating electrostatic force is generated, and the resonant beam (52) vibrates in a plane parallel to the surface of the substrate (9) by the electrostatic force. Due to the vibration of the resonance beam (52), the capacitance between the resonance beam (52) and both electrodes changes, and the change in capacitance is output as a high-frequency signal from the other anchor (3).
或いは、一方の電極には高周波電源(図示省略)が接続されると共に、一方のアンカー(3)には主電圧電源(図示省略)が接続されて、他方の電極から高周波信号が出力される。
この場合、一方のアンカー(3)を介して共振ビーム(52)に直流電圧を印加した状態で、一方の電極に高周波信号を入力すると、共振ビーム(52)と前記一方の電極との間にギャップ部を介して交番静電気力が発生し、該静電気力によって共振ビーム(52)が基板(9)の表面と平行な面内で振動する。この共振ビーム(52)の振動により、共振ビーム(52)と両電極の間の静電容量が変化し、該静電容量の変化が他方の電極から高周波信号として出力される。
Alternatively, a high frequency power source (not shown) is connected to one electrode, and a main voltage power source (not shown) is connected to one anchor (3), and a high frequency signal is output from the other electrode.
In this case, when a DC voltage is applied to the resonant beam (52) via one anchor (3) and a high frequency signal is input to one electrode, the resonant beam (52) and the one electrode are placed between each other. An alternating electrostatic force is generated through the gap portion, and the resonant beam (52) vibrates in a plane parallel to the surface of the substrate (9) by the electrostatic force. Due to the vibration of the resonance beam (52), the capacitance between the resonance beam (52) and both electrodes changes, and the change in capacitance is output as a high-frequency signal from the other electrode.
ここで、共振ビーム(52)に対して各ギャップ部を介して作用する静電気力は、その変動幅が共振ビーム(52)の中央部近傍のギャップ部で最も小さく且つ両端部近傍のギャップ部で最も大きくなる様に設定されている。
即ち、図1の場合、共振ビーム(52)の中央の非くびれ部(53)と電極突出部(10)との間に作用する交番静電気力の変動幅のピーク値をFa、両側の非くびれ部(53)(53)と電極突出部(20)(20)との間に作用する交番静電気力の変動幅のピーク値をFbとすると、Fa<Fbの大小関係となる様に設定されている。
Here, the electrostatic force acting on the resonant beam (52) through each gap portion has the smallest fluctuation width in the gap portion near the center portion of the resonant beam (52) and in the gap portions near both ends. It is set to be the largest.
That is, in the case of FIG. 1, the peak value of the fluctuation range of the alternating electrostatic force acting between the non-constricted portion (53) at the center of the resonant beam (52) and the electrode protruding portion (10) is Fa, and the non-constricted on both sides. When the peak value of the fluctuation range of the alternating electrostatic force acting between the parts (53) and (53) and the electrode protrusions (20) and (20) is Fb, the magnitude relationship is set so that Fa <Fb. Yes.
上記の大小関係を実現するための具体的な構成としては、図2に示す様に、1つの電極突出部(10)を有する第1の電極と2つの電極突出部(20)(20)を有する第2の電極の両方に高周波電源(6)を接続すると共に、第2の電極には、バイアス電圧電源(60)を接続する構成を採用することが出来る。 As a specific configuration for realizing the above-described magnitude relationship, as shown in FIG. 2, a first electrode having one electrode protrusion (10) and two electrode protrusions (20) (20) are provided. It is possible to adopt a configuration in which a high frequency power source (6) is connected to both of the second electrodes, and a bias voltage power source (60) is connected to the second electrode.
又、図3に示す様に、共振ビーム(52)の両端間に形成されている3つのギャップ部の内、中央の非くびれ部が面するギャップ部のギャップ長をGa、両端の非くびれ部が面するギャップ部のギャップ長をGbとすると、Ga>Gbの大小関係となる様に設定されている。 Further, as shown in FIG. 3, among the three gap portions formed between both ends of the resonant beam (52), the gap length of the gap portion facing the central non-constricted portion is Ga, and the non-constricted portions at both ends are formed. When the gap length of the gap portion facing is Gb, Ga> Gb is set so as to have a magnitude relationship.
或いは、図4に示す様に、共振ビーム(52)の両端間に形成されている3つのギャップ部の内、中央の非くびれ部が面するギャップ部の幅をWa、両端の非くびれ部が面するギャップ部の幅をWbとすると、Wa<Wbの大小関係となる様に設定されている。 Alternatively, as shown in FIG. 4, among three gap portions formed between both ends of the resonant beam (52), the width of the gap portion facing the central non-constricted portion is Wa, and the non-constricted portions at both ends are When the width of the facing gap portion is Wb, the size relationship is set such that Wa <Wb.
図1に示す本発明のマイクロメカニカル共振器と、従来のマイクロメカニカル共振器、即ち、共振ビーム(52)にくびれ部を有せず、且つ共振ビーム(52)の中央部に作用する交番静電気力のピーク値Faと両側部に作用する交番静電気力のピーク値Fbを同一(Fa=Fb)としたマイクロメカニカル共振器とを対象として、1次共振モード、3次共振モード及び5次共振モードのそれぞれについての周波数特性をコンピュータシミュレーションにより計算した。図5及び図6はそれぞれ従来のマイクロメカニカル共振器と本発明のマイクロメカニカル共振器についての計算結果を表わしている。 The micromechanical resonator of the present invention shown in FIG. 1 and the conventional micromechanical resonator, that is, the alternating electrostatic force acting on the central portion of the resonant beam (52) without the constricted portion in the resonant beam (52). The first resonance mode, the third resonance mode, and the fifth resonance mode are targeted for a micromechanical resonator having the same peak value Fa and the alternating electrostatic force peak value Fb acting on both sides (Fa = Fb). The frequency characteristics for each were calculated by computer simulation. 5 and 6 show the calculation results for the conventional micromechanical resonator and the micromechanical resonator of the present invention, respectively.
尚、従来のマイクロメカニカル共振器においては交番静電気力のピーク値Fa、Fbを共に0.01MPaに設定し、本発明のマイクロメカニカル共振器においては交番静電気力のピーク値FaとFbをそれぞれ0.0086MPaと0.01MPaに設定した。 In the conventional micromechanical resonator, the peak values Fa and Fb of the alternating electrostatic force are both set to 0.01 MPa, and in the micromechanical resonator of the present invention, the peak values Fa and Fb of the alternating electrostatic force are each set to 0.1 MPa. The pressure was set to 0086 MPa and 0.01 MPa.
従来のマイクロメカニカル共振器においては図5から明らかな様に、1次共振モードのハーモニック変位が最も大きく、3次共振モードのハーモニック変位や5次共振モードのハーモニック変位はそれよりも小さくなっているのに対し、本発明のマイクロメカニカル共振器においては図6から明らかな様に、1次共振モードのハーモニック変位が抑制されて、3次共振モードのハーモニック変位が最も大きくなっている。 In the conventional micromechanical resonator, as is clear from FIG. 5, the harmonic displacement in the primary resonance mode is the largest, and the harmonic displacement in the tertiary resonance mode and the harmonic displacement in the fifth resonance mode are smaller than that. On the other hand, in the micromechanical resonator of the present invention, as apparent from FIG. 6, the harmonic displacement in the primary resonance mode is suppressed and the harmonic displacement in the tertiary resonance mode is the largest.
この様に本発明に係るマイクロメカニカル共振器によれば、1次共振モードの振動が抑制されて、高次共振モードの振動が増大するので、その高次共振モードを利用することによって、従来よりも高い周波数帯域で動作する高周波無線通信機器を容易に構成することが出来る。 As described above, according to the micromechanical resonator according to the present invention, the vibration of the first-order resonance mode is suppressed and the vibration of the higher-order resonance mode is increased. In addition, it is possible to easily configure a high-frequency wireless communication device that operates in a high frequency band.
尚、4次モード共振モードや5次共振モードを得るため、共振ビーム(52)のくびれ部の数が図14(a)に示す様に4つから、同図(b)(c)に示す様に5つや6つに増加し、それぞれの非くびれ部に第1、第2の電極を配置した場合も同様に、共振ビーム(52)に対して作用する静電気力の変動幅が、共振ビーム(52)の中央部近傍で最も小さく且つ両端部近傍で最も大きくなる様に設定する。例えば、同図(b)の場合はFa<Fbに設定し、同図(c)の場合はFa<Fb<Fcに設定する。 In order to obtain the fourth-order mode resonance mode and the fifth-order resonance mode, the number of constricted portions of the resonant beam (52) is four as shown in FIG. 14 (a), and shown in FIGS. Similarly, when the first and second electrodes are arranged in the respective non-constricted portions, the fluctuation range of the electrostatic force acting on the resonant beam (52) is similar to that of the resonant beam. It is set so that it is the smallest in the vicinity of the center of (52) and the largest in the vicinity of both ends. For example, Fa <Fb is set in the case of FIG. 5B, and Fa <Fb <Fc is set in the case of FIG.
図7〜図13は、本発明に係るマイクロメカニカル共振器の具体的な実施例を示している。
第1実施例
図7及び図8に示すマイクロメカニカル共振器においては、シリコン或いはガラスからなる基板(9)上に、シリコン、アルミニウム等の導電材料からなる共振子(5)が配備されると共に、該共振子(5)の両側には、シリコン、アルミニウム等の導電材料からなる一対の駆動電極(1)(2)が配備されている。
7 to 13 show specific embodiments of the micromechanical resonator according to the present invention.
First Embodiment In the micromechanical resonator shown in FIGS. 7 and 8, a resonator (5) made of a conductive material such as silicon or aluminum is disposed on a substrate (9) made of silicon or glass, On both sides of the resonator (5), a pair of drive electrodes (1) and (2) made of a conductive material such as silicon and aluminum are provided.
共振子(5)は、長さが例えば10〜20μmの角柱状の共振ビーム(52)と、該共振ビーム(52)の両端部に互いに平行に突設された一対の支持ビーム(51)(51)とを具えて、全体がH字状に形成されている。共振ビーム(52)には、その長手方向の7カ所にくびれ部が等間隔に凹設されている。各支持ビーム(51)の両端部は、それぞれシリコン、アルミニウム等の導電材料からなるアンカー(3)によって、基板(9)の表面に固定されており、これによって、共振子(5)は、基板(9)の表面から僅かに浮上した位置に保持されている。
又、共振子(5)の両支持ビーム(51)(51)の外側には、それぞれ支持ビーム(51)の中央部に対向して、一対のバイアス電極(4)(4)が配備されており、支持ビーム(51)とバイアス電極(4)の間には所定(例えば0.1〜0.5μm)のギャップが形成されている。
The resonator (5) includes a prismatic resonant beam (52) having a length of, for example, 10 to 20 μm, and a pair of support beams (51) (51) (projected parallel to both ends of the resonant beam (52)). 51) and the whole is formed in an H shape. In the resonant beam (52), constricted portions are recessed at equal intervals at seven locations in the longitudinal direction. Both ends of each support beam (51) are fixed to the surface of the substrate (9) by anchors (3) made of a conductive material such as silicon and aluminum, whereby the resonator (5) It is held at a position slightly lifted from the surface of (9).
In addition, a pair of bias electrodes (4) and (4) are arranged outside the both support beams (51) and (51) of the resonator (5) so as to face the central portion of the support beam (51). A predetermined gap (for example, 0.1 to 0.5 μm) is formed between the
一対の駆動電極(1)(2)はそれぞれ、基部(11)(21)と、該基部(11)(21)から共振ビーム(52)へ向けて等間隔に突設された3つの電極突出部(10)(20)とを具えて、全体が櫛歯状を呈している。
一方の駆動電極(1)の3つの電極突出部(10)(10)(10)と他方の駆動電極(2)の3つの電極突出部(20)(20)(20)はそれぞれ、基板(9)の表面と平行な面内で、共振ビーム(52)の非くびれ部と交互に対向して、共振ビーム(52)の非くびれ部との間に所定(例えば0.1〜0.5μm)のギャップ部Gを形成している。
Each of the pair of drive electrodes (1) and (2) has a base part (11) (21) and three electrode protrusions protruding from the base part (11) (21) toward the resonance beam (52) at equal intervals. The parts (10) and (20) have a comb-like shape as a whole.
The three electrode protrusions (10), (10), and (10) of one drive electrode (1) and the three electrode protrusions (20), (20), and (20) of the other drive electrode (2) are each a substrate ( 9) In a plane parallel to the surface of the resonance beam (52), it is alternately opposed to the non-constricted portion of the resonant beam (52), and between the non-constricted portion of the resonant beam (52) (for example, 0.1 to 0.5 μm). ) Gap portion G is formed.
図8に示す如く、一対の駆動電極(1)(2)には高周波電源(6)が接続され、1つのアンカー(3)には主電圧電源(7)が接続されている。又、一対のバイアス電極(4)(4)にはバイアス電圧電源(8)が接続されている。
斯くして、図7及び図8に示すマイクロメカニカル共振器は、高周波電源(6)から2つの駆動電極(1)(2)に高周波信号が入力されて、1つのアンカー(3)から高周波信号Ioが出力される1ポート型の共振器を構成している。
As shown in FIG. 8, a high frequency power source (6) is connected to the pair of drive electrodes (1) and (2), and a main voltage power source (7) is connected to one anchor (3). A bias voltage power source (8) is connected to the pair of bias electrodes (4) (4).
Thus, in the micromechanical resonator shown in FIGS. 7 and 8, a high frequency signal is input from the high frequency power source (6) to the two drive electrodes (1) and (2), and the high frequency signal is output from one anchor (3). This constitutes a one-port type resonator that outputs Io.
上記のマイクロメカニカル共振器において、アンカー(3)を介して共振子(5)に直流電圧Vpを印加した状態で、両駆動電極(1)(2)に高周波信号を入力すると、電極突出部(10)(20)と支持ビーム(51)の非くびれ部との間に静電気力が発生し、この静電気力によって、共振子(5)の共振ビーム(52)は、その両端部を支持部(50)(50)として、基板(9)の表面と平行な面内で振動することになる。
電極突出部(10)(20)と共振ビーム(52)の非くびれ部との間に発生させるべき静電気力は、上述の如く、共振ビーム(52)の中央部近傍のギャップ部で最も小さく且つ両端部近傍のギャップ部で最も大きくなる様に設定される。
In the above micro mechanical resonator, when a DC voltage Vp is applied to the resonator (5) via the anchor (3) and a high frequency signal is input to both the drive electrodes (1) and (2), the electrode protrusion ( 10) An electrostatic force is generated between the (20) and the non-constricted portion of the support beam (51), and this electrostatic force causes the resonance beam (52) of the resonator (5) to be supported by the support portions ( 50) and 50) vibrate in a plane parallel to the surface of the substrate (9).
As described above, the electrostatic force to be generated between the electrode protrusions (10) and (20) and the non-constricted portion of the resonant beam (52) is the smallest in the gap near the center of the resonant beam (52) and The gap is set to be the largest in the gap near the both ends.
共振子(5)の共振ビーム(52)は、くびれ部が振動の節、非くびれ部が振動の腹となって振動し、この振動に伴って、共振ビーム(52)と両駆動電極(1)(2)との間に形成される静電容量が変化し、該静電容量の変化が他の1つのアンカー(3)から高周波信号Ioとして出力される。 The resonance beam (52) of the resonator (5) vibrates with the constricted portion as a vibration node and the non-constricted portion as an antinode of vibration. With this vibration, the resonant beam (52) and both drive electrodes (1) are vibrated. ) And (2) change in capacitance, and the change in capacitance is output as a high-frequency signal Io from the other anchor (3).
ここで、バイアス電極(4)(4)にバイアス電圧を印加することにより、共振子(5)の支持ビーム(51)(51)とバイアス電極(4)(4)との間に静電気力が発生し、これによって共振子(5)の共振ビーム(52)は、長手方向の引っ張り力を受けることになる。
従って、バイアス電圧電源(8)のバイアス電圧を調整することにより、共振ビーム(52)の共振周波数を変化させて、アンカー(3)から出力される高周波信号Ioの周波数を微調整することが出来る。
Here, by applying a bias voltage to the bias electrodes (4) and (4), an electrostatic force is generated between the support beams (51) and (51) of the resonator (5) and the bias electrodes (4) and (4). This causes the resonant beam (52) of the resonator (5) to receive a tensile force in the longitudinal direction.
Therefore, by adjusting the bias voltage of the bias voltage power supply (8), the resonant frequency of the resonant beam (52) can be changed to finely adjust the frequency of the high-frequency signal Io output from the anchor (3). .
上述のマイクロメカニカル共振器によれば、共振子(5)の共振ビーム(52)の長手方向に沿って、複数の電極突出部(10)(20)を交互に配置することにより、その電極突出部(10)(20)の数に応じた高次の共振モードで共振ビーム(52)を意図的に共振させて、GHz帯の発振周波数を得ることが出来る。 According to the above-described micromechanical resonator, the electrode protrusions are arranged by alternately arranging the plurality of electrode protrusions (10) and (20) along the longitudinal direction of the resonance beam (52) of the resonator (5). The resonant beam (52) can be intentionally resonated in a higher-order resonance mode corresponding to the number of sections (10) and (20), and an oscillation frequency in the GHz band can be obtained.
第2実施例
図9に示すマイクロメカニカル共振器においては、シリコン或いはガラスからなる基板(9)上に、シリコン、アルミニウム等の導電材料からなる共振子(5)が配備されると共に、該共振子(5)の両側には、シリコン、アルミニウム等の導電材料からなる入力電極(22)と出力電極(12)が配備されている。
Second Embodiment In the micromechanical resonator shown in FIG. 9, a resonator (5) made of a conductive material such as silicon or aluminum is disposed on a substrate (9) made of silicon or glass, and the resonator. On both sides of (5), an input electrode (22) and an output electrode (12) made of a conductive material such as silicon or aluminum are provided.
共振子(5)は、第1実施例と同じ構造を有し、共振子(5)の両支持ビーム(51)(51)の外側には、それぞれ支持ビーム(51)の中央部に対向して、一対のバイアス電極(4)(4)が配備されており、支持ビーム(51)とバイアス電極(4)の間には所定(例えば0.1〜0.5μm)のギャップが形成されている。 The resonator (5) has the same structure as that of the first embodiment. The resonator (5) is opposed to the central portion of the support beam (51) on the outside of the support beams (51) and (51) of the resonator (5). A pair of bias electrodes (4) and (4) is provided, and a predetermined gap (for example, 0.1 to 0.5 μm) is formed between the support beam (51) and the bias electrode (4). Yes.
入力電極(22)及び出力電極(12)はそれぞれ、基部(23)(13)と、該基部(23)(13)から共振ビーム(52)へ向けて等間隔に突設された3つの電極突出部(24)(14)とを具えて、全体が櫛歯状を呈している。
入力電極(22)の3つの電極突出部(24)(24)(24)と出力電極(12)の3つの電極突出部(14)(14)(14)はそれぞれ、基板(9)の表面と平行な面内で、共振ビーム(52)の非くびれ部と交互に対向して、共振ビーム(52)の非くびれ部との間に所定(例えば0.1〜0.5μm)のギャップ部Gを形成している。
Each of the input electrode (22) and the output electrode (12) includes a base (23) (13) and three electrodes projecting at equal intervals from the base (23) (13) toward the resonance beam (52). The projecting portions (24) and (14) are provided, and the whole has a comb-teeth shape.
The three electrode protrusions (24), (24) and (24) of the input electrode (22) and the three electrode protrusions (14), (14) and (14) of the output electrode (12) are the surfaces of the substrate (9), respectively. In a plane parallel to the non-necked portion of the resonant beam (52) and a predetermined gap (for example, 0.1 to 0.5 μm) between the non-necked portion of the resonant beam (52). G is formed.
入力電極(22)には高周波電源(6)が接続され、1つのアンカー(3)には主電圧電源(7)が接続されている。又、一対のバイアス電極(4)(4)にはバイアス電圧電源(8)が接続されている。
斯くして、図9に示すマイクロメカニカル共振器は、高周波電源(6)から入力電極(22)に高周波信号が入力されて、出力電極(12)から高周波信号Ioが出力される2ポート型の共振器を構成している。
A high frequency power source (6) is connected to the input electrode (22), and a main voltage power source (7) is connected to one anchor (3). A bias voltage power source (8) is connected to the pair of bias electrodes (4) (4).
Thus, the micromechanical resonator shown in FIG. 9 is a two-port type in which a high frequency signal is input from the high frequency power source (6) to the input electrode (22) and a high frequency signal Io is output from the output electrode (12). It constitutes a resonator.
上記のマイクロメカニカル共振器において、アンカー(3)を介して共振子(5)に直流電圧Vpを印加した状態で、入力電極(22)に高周波信号を入力すると、電極突出部(24)と支持ビーム(51)の非くびれ部との間に静電気力が発生し、この静電気力によって、共振子(5)の共振ビーム(52)は、その両端部を支持部(50)(50)として、基板(9)の表面と平行な面内で振動することになる。
電極突出部(10)と共振ビーム(52)の非くびれ部との間に発生させるべき静電気力は、上述の如く、共振ビーム(52)の中央部近傍のギャップ部で最も小さく且つ両端部近傍のギャップ部で最も大きくなる様に設定される。
In the above micro mechanical resonator, when a high frequency signal is input to the input electrode (22) with the DC voltage Vp applied to the resonator (5) via the anchor (3), the electrode protrusion (24) and the support are supported. An electrostatic force is generated between the beam (51) and the non-constricted portion, and the electrostatic force causes the resonant beam (52) of the resonator (5) to have both ends as support portions (50) and (50). It vibrates in a plane parallel to the surface of the substrate (9).
As described above, the electrostatic force to be generated between the electrode protrusion (10) and the non-constricted portion of the resonant beam (52) is the smallest in the gap near the center of the resonant beam (52) and near both ends. It is set to be the largest in the gap portion.
共振子(5)の共振ビーム(52)は、くびれ部が振動の節、非くびれ部が振動の腹となって振動し、この振動に伴って、共振ビーム(52)と出力電極(12)との間に形成される静電容量が変化し、該静電容量の変化が出力電極(12)から高周波信号Ioとして出力される。
The resonant beam (52) of the resonator (5) vibrates with the constricted part serving as a vibration node and the non-constricted part serving as an antinode, and along with this vibration, the resonant beam (52) and the output electrode (12). The electrostatic capacity formed between the
ここで、バイアス電極(4)(4)にバイアス電圧を印加することにより、共振子(5)の支持ビーム(51)(51)とバイアス電極(4)(4)との間に静電気力が発生し、これによって共振子(5)の共振ビーム(52)は、長手方向の引っ張り力を受けることになる。
従って、バイアス電圧電源(8)のバイアス電圧を調整することにより、共振ビーム(52)の共振周波数を変化させて、アンカー(3)から出力される高周波信号Ioの周波数を微調整することが出来る。
Here, by applying a bias voltage to the bias electrodes (4) and (4), an electrostatic force is generated between the support beams (51) and (51) of the resonator (5) and the bias electrodes (4) and (4). This causes the resonant beam (52) of the resonator (5) to receive a tensile force in the longitudinal direction.
Therefore, by adjusting the bias voltage of the bias voltage power supply (8), the resonant frequency of the resonant beam (52) can be changed to finely adjust the frequency of the high-frequency signal Io output from the anchor (3). .
上述のマイクロメカニカル共振器によれば、共振子(5)の共振ビーム(52)の長手方向に沿って、複数の電極突出部(14)(24)を交互に配置することにより、その電極突出部(14)(24)の数に応じた高次の共振モードで共振ビーム(52)を意図的に共振させて、GHz帯の発振周波数を得ることが出来る。 According to the above-described micromechanical resonator, the electrode protrusions are arranged by alternately arranging the plurality of electrode protrusions (14) and (24) along the longitudinal direction of the resonance beam (52) of the resonator (5). The resonant beam (52) can be intentionally resonated in a higher-order resonance mode corresponding to the number of the parts (14) and (24), and an oscillation frequency in the GHz band can be obtained.
第3実施例
図10に示すマイクロメカニカル共振器においては、シリコン或いはガラスからなる基板(9)上に、シリコン、アルミニウム等の導電材料からなる共振子(5)が配備されると共に、該共振子(5)の両側には、シリコン、アルミニウム等の導電材料からなる一対の駆動電極(15)(25)が配備されている。
Third Embodiment In the micromechanical resonator shown in FIG. 10, a resonator (5) made of a conductive material such as silicon or aluminum is disposed on a substrate (9) made of silicon or glass, and the resonator. On both sides of (5), a pair of drive electrodes (15), (25) made of a conductive material such as silicon or aluminum is provided.
共振子(5)は、第1実施例と同じ構造を有し、共振子(5)の両支持ビーム(51)(51)の外側には、それぞれ支持ビーム(51)の中央部に対向して、一対のバイアス電極(4)(4)が配備されており、支持ビーム(51)とバイアス電極(4)の間には所定(例えば0.1〜0.5μm)のギャップが形成されている。 The resonator (5) has the same structure as that of the first embodiment. The resonator (5) is opposed to the central portion of the support beam (51) on the outside of the support beams (51) and (51) of the resonator (5). A pair of bias electrodes (4) and (4) is provided, and a predetermined gap (for example, 0.1 to 0.5 μm) is formed between the support beam (51) and the bias electrode (4). Yes.
一方の駆動電極(15)は、共振ビーム(52)の下方、即ち共振ビーム(52)と基板(9)の間へ向けて等間隔に突出する3つの電極突出部(16)(16)(16)を具え、他方の駆動電極(25)は、共振ビーム(52)の上方へ向けて等間隔に突出する3つの電極突出部(26)(26)(26)を具えている。
一方の駆動電極(15)の3つの電極突出部(16)(16)(16)と他方の駆動電極(25)の3つの電極突出部(26)(26)(26)はそれぞれ、基板(9)の表面と垂直な面内で、共振ビーム(52)の非くびれ部と交互に対向して、共振ビーム(52)の非くびれ部との間に所定(例えば0.1〜0.5μm)のギャップ部を形成している。
One drive electrode (15) has three electrode protrusions (16), (16), which protrude at equal intervals below the resonance beam (52), that is, between the resonance beam (52) and the substrate (9). 16), and the other drive electrode (25) includes three electrode protrusions (26), (26), (26) protruding upward at equal intervals toward the resonance beam (52).
The three electrode protrusions (16), (16), (16) of one drive electrode (15) and the three electrode protrusions (26), (26), (26) of the other drive electrode (25) are each a substrate ( 9) In a plane perpendicular to the surface of the resonant beam (52), it is alternately opposed to the non-constricted portion of the resonant beam (52), and between the non-constricted portion of the resonant beam (52) (for example, 0.1 to 0.5 μm). ) Is formed.
一対の駆動電極(15)(25)には高周波電源(6)が接続され、1つのアンカー(3)には主電圧電源(7)が接続されている。又、一対のバイアス電極(4)(4)にはバイアス電圧電源(8)が接続されている。
斯くして、図10に示すマイクロメカニカル共振器は、高周波電源(6)から2つの駆動電極(15)(25)に高周波信号が入力されて、1つのアンカー(3)から高周波信号Ioが出力される1ポート型の共振器を構成している。
A high frequency power source (6) is connected to the pair of drive electrodes (15) and (25), and a main voltage power source (7) is connected to one anchor (3). A bias voltage power source (8) is connected to the pair of bias electrodes (4) (4).
Thus, the micromechanical resonator shown in FIG. 10 receives a high frequency signal from the high frequency power source (6) to the two drive electrodes (15) and (25) and outputs a high frequency signal Io from one anchor (3). This constitutes a 1-port type resonator.
上記のマイクロメカニカル共振器において、アンカー(3)を介して共振子(5)に直流電圧Vpを印加した状態で、両駆動電極(15)(25)に高周波信号を入力すると、電極突出部(16)(26)と支持ビーム(51)の非くびれ部との間に静電気力が発生し、この静電気力によって、共振子(5)の共振ビーム(52)は、その両端部を支持部(50)(50)として、基板(9)の表面と垂直な面内で振動することになる。
電極突出部(16)(26)と共振ビーム(52)の非くびれ部との間に発生させるべき静電気力は、上述の如く、共振ビーム(52)の中央部近傍のギャップ部で最も小さく且つ両端部近傍のギャップ部で最も大きくなる様に設定される。
In the above-described micromechanical resonator, when a high frequency signal is input to the
As described above, the electrostatic force to be generated between the electrode protrusions (16), (26) and the non-constricted portion of the resonant beam (52) is the smallest in the gap near the center of the resonant beam (52) and The gap is set to be the largest in the gap near the both ends.
共振子(5)の共振ビーム(52)は、図11に示す様に、くびれ部が振動の節、非くびれ部が振動の腹となって振動し、この振動に伴って、共振ビーム(52)と両駆動電極(1)(2)との間に形成される静電容量が変化し、該静電容量の変化が他の1つのアンカー(3)から高周波信号Ioとして出力される。 As shown in FIG. 11, the resonance beam (52) of the resonator (5) vibrates with the constricted portion serving as a vibration node and the non-constricted portion serving as an antinode of vibration. ) And the drive electrodes (1) and (2) change, and the change in capacitance is output as a high-frequency signal Io from the other anchor (3).
ここで、バイアス電極(4)(4)にバイアス電圧を印加することにより、共振子(5)の支持ビーム(51)(51)とバイアス電極(4)(4)との間に静電気力が発生し、これによって共振子(5)の共振ビーム(52)は、長手方向の引っ張り力を受けることになる。
従って、バイアス電圧電源(8)のバイアス電圧を調整することにより、共振ビーム(52)の共振周波数を変化させて、アンカー(3)から出力される高周波信号Ioの周波数を微調整することが出来る。
Here, by applying a bias voltage to the bias electrodes (4) and (4), an electrostatic force is generated between the support beams (51) and (51) of the resonator (5) and the bias electrodes (4) and (4). This causes the resonant beam (52) of the resonator (5) to receive a tensile force in the longitudinal direction.
Therefore, by adjusting the bias voltage of the bias voltage power supply (8), the resonant frequency of the resonant beam (52) can be changed to finely adjust the frequency of the high-frequency signal Io output from the anchor (3). .
上述のマイクロメカニカル共振器によれば、共振子(5)の共振ビーム(52)の長手方向に沿って、複数の電極突出部(16)(26)を交互に配置することにより、その電極突出部(16)(26)の数に応じた高次の共振モードで共振ビーム(52)を意図的に共振させて、GHz帯の発振周波数を得ることが出来る。 According to the above-described micromechanical resonator, the plurality of electrode protrusions (16) and (26) are alternately arranged along the longitudinal direction of the resonance beam (52) of the resonator (5), thereby forming the electrode protrusions. The resonant beam (52) can be intentionally resonated in a higher-order resonance mode corresponding to the number of the parts (16) and (26), and an oscillation frequency in the GHz band can be obtained.
第4実施例
図12に示すマイクロメカニカル共振器においては、シリコン或いはガラスからなる基板(9)上に、シリコン、アルミニウム等の導電材料からなる共振子(5)が配備されると共に、該共振子(5)の両側には、シリコン、アルミニウム等の導電材料からなる入力電極(27)と出力電極(17)が配備されている。
Fourth Embodiment In the micromechanical resonator shown in FIG. 12, a resonator (5) made of a conductive material such as silicon or aluminum is disposed on a substrate (9) made of silicon or glass, and the resonator. On both sides of (5), an input electrode (27) and an output electrode (17) made of a conductive material such as silicon or aluminum are provided.
共振子(5)は、第1実施例と同じ構造を有し、共振子(5)の両支持ビーム(51)(51)の外側には、それぞれ支持ビーム(51)の中央部に対向して、一対のバイアス電極(4)(4)が配備されており、支持ビーム(51)とバイアス電極(4)の間には所定(例えば0.1〜0.5μm)のギャップが形成されている。 The resonator (5) has the same structure as that of the first embodiment. The resonator (5) is opposed to the central portion of the support beam (51) on the outside of the support beams (51) and (51) of the resonator (5). A pair of bias electrodes (4) and (4) is provided, and a predetermined gap (for example, 0.1 to 0.5 μm) is formed between the support beam (51) and the bias electrode (4). Yes.
入力電極(27)及び出力電極(17)はそれぞれ、共振ビーム(52)の下方、即ち共振ビーム(52)と基板(9)の間へ向けて等間隔に突出する3つの電極突出部(28)(18)を具え、これらの電極突出部(28)(18)はそれぞれ、基板(9)の表面と垂直な面内で、共振ビーム(52)の非くびれ部と交互に対向して、共振ビーム(52)の非くびれ部との間に所定(例えば0.1〜0.5μm)のギャップ部を形成している。
The input electrode (27) and the output electrode (17) each have three electrode protrusions (28) protruding at equal intervals below the resonance beam (52), that is, between the resonance beam (52) and the substrate (9). ) (18), and these electrode protrusions (28) and (18) are alternately opposed to the non-constricted portions of the resonant beam (52) in a plane perpendicular to the surface of the substrate (9), A predetermined gap (for example, 0.1 to 0.5 μm) is formed between the
入力電極(27)には高周波電源(6)が接続され、1つのアンカー(3)には主電圧電源(7)が接続されている。又、一対のバイアス電極(4)(4)にはバイアス電圧電源(8)が接続されている。
斯くして、図12に示すマイクロメカニカル共振器は、高周波電源(6)から入力電極(27)に高周波信号が入力されて、出力電極(17)から高周波信号Ioが出力される2ポート型の共振器を構成している。
A high frequency power source (6) is connected to the input electrode (27), and a main voltage power source (7) is connected to one anchor (3). A bias voltage power source (8) is connected to the pair of bias electrodes (4) (4).
Thus, the micromechanical resonator shown in FIG. 12 is a two-port type in which a high frequency signal is input from the high frequency power source (6) to the input electrode (27) and a high frequency signal Io is output from the output electrode (17). It constitutes a resonator.
上記のマイクロメカニカル共振器において、アンカー(3)を介して共振子(5)に直流電圧Vpを印加した状態で、入力電極(27)に高周波信号を入力すると、電極突出部(28)と支持ビーム(51)の非くびれ部との間に静電気力が発生し、この静電気力によって、共振子(5)の共振ビーム(52)は、その両端部を支持部(50)(50)として、基板(9)の表面と垂直な面内で振動することになる。
電極突出部(28)と共振ビーム(52)の非くびれ部との間に発生させるべき静電気力は、上述の如く、共振ビーム(52)の中央部近傍のギャップ部で最も小さく且つ両端部近傍のギャップ部で最も大きくなる様に設定される。
In the above micro mechanical resonator, when a high frequency signal is input to the input electrode (27) with the DC voltage Vp applied to the resonator (5) via the anchor (3), the electrode protrusion (28) and the support are supported. An electrostatic force is generated between the beam (51) and the non-constricted portion, and the electrostatic force causes the resonant beam (52) of the resonator (5) to have both ends as support portions (50) and (50). It vibrates in a plane perpendicular to the surface of the substrate (9).
The electrostatic force to be generated between the electrode protrusion (28) and the non-constricted portion of the resonant beam (52) is the smallest in the gap near the center of the resonant beam (52) and near both ends as described above. It is set to be the largest in the gap portion.
共振子(5)の共振ビーム(52)は、図13に示す様に、くびれ部が振動の節、非くびれ部が振動の腹となって振動し、この振動に伴って、共振ビーム(52)と出力電極(17)との間に形成される静電容量が変化し、該静電容量の変化が出力電極(17)から高周波信号Ioとして出力される。 As shown in FIG. 13, the resonance beam (52) of the resonator (5) vibrates with the constricted portion serving as a vibration node and the non-constricted portion serving as an antinode of vibration. ) And the output electrode (17) change, and the change in capacitance is output from the output electrode (17) as a high-frequency signal Io.
ここで、バイアス電極(4)(4)にバイアス電圧を印加することにより、共振子(5)の支持ビーム(51)(51)とバイアス電極(4)(4)との間に静電気力が発生し、これによって共振子(5)の共振ビーム(52)は、長手方向の引っ張り力を受けることになる。
従って、バイアス電圧電源(8)のバイアス電圧を調整することにより、共振ビーム(52)の共振周波数を変化させて、アンカー(3)から出力される高周波信号Ioの周波数を微調整することが出来る。
Here, by applying a bias voltage to the bias electrodes (4) and (4), an electrostatic force is generated between the support beams (51) and (51) of the resonator (5) and the bias electrodes (4) and (4). This causes the resonant beam (52) of the resonator (5) to receive a tensile force in the longitudinal direction.
Therefore, by adjusting the bias voltage of the bias voltage power supply (8), the resonant frequency of the resonant beam (52) can be changed to finely adjust the frequency of the high-frequency signal Io output from the anchor (3). .
上述のマイクロメカニカル共振器によれば、共振子(5)の共振ビーム(52)の長手方向に沿って、複数の電極突出部(18)(28)を交互に配置することにより、その電極突出部(18)(28)の数に応じた高次の共振モードで共振ビーム(52)を意図的に共振させて、GHz帯の発振周波数を得ることが出来る。 According to the above-described micromechanical resonator, the plurality of electrode protrusions (18) and (28) are alternately arranged along the longitudinal direction of the resonance beam (52) of the resonator (5), whereby the electrode protrusions are arranged. The resonant beam (52) can be intentionally resonated in a higher-order resonance mode corresponding to the number of sections (18) and (28), and an oscillation frequency in the GHz band can be obtained.
上記の様に、本発明に係るマイクロメカニカル共振器によれば、共振子(5)の共振ビーム(52)に高次モードの振動を意図的に発生させることが出来るので、共振子(5)を作製容易な寸法に維持したまま、従来よりも高い発振周波数を得ることが出来る。又、バイアス電圧電源(8)の電圧調整により、共振子(5)の形状寸法を変更することなく、発振周波数の微調整を行なうことが出来る。 As described above, according to the micromechanical resonator of the present invention, the resonance beam (52) of the resonator (5) can intentionally generate vibrations of higher order modes, so that the resonator (5) Thus, an oscillation frequency higher than that of the prior art can be obtained while maintaining the dimensions that are easy to manufacture. Further, by adjusting the voltage of the bias voltage power source (8), the oscillation frequency can be finely adjusted without changing the shape and dimension of the resonator (5).
更に又、本発明に係るマイクロメカニカル共振器によれば、共振ビーム(52)に作用する静電気力を共振ビーム(52)の中央部から両端部に向かって増大させると共に、共振ビーム(52)の振動の節となる位置にくびれ部を凹設した構成により、共振ビーム(52)に発生する高次共振モードの振動波形は、該波形に含まれる複数のピーク値が互いに等しくなる理想的なものに近づき、その結果、1次の共振モードの振動が抑えられて高次の共振モードの振動が増大することになる。従って、発振周波数の高い高次共振モードを利用した無線通信装置への応用が可能となる。 Furthermore, according to the micromechanical resonator of the present invention, the electrostatic force acting on the resonant beam (52) is increased from the central portion toward both ends of the resonant beam (52), and the resonant beam (52) The vibration waveform of the higher-order resonance mode generated in the resonant beam (52) is ideal because the peak value contained in the waveform is equal to each other due to the constricted concavity at the position that becomes the vibration node. As a result, the vibration of the first-order resonance mode is suppressed, and the vibration of the higher-order resonance mode is increased. Therefore, application to a wireless communication device using a higher-order resonance mode having a high oscillation frequency is possible.
特に、本発明に係るマイクロメカニカル共振器は、出力される高周波信号の周波数を挺倍することなく、直接に必要な周波数を発振させることが出来るので、低位相ノイズが必要とされる装置、例えばリモートキーレスエントリーシステムや、スペクトラム拡散通信やソフトウエア無線等のRF無線装置に有効である。 In particular, the micromechanical resonator according to the present invention can oscillate a necessary frequency directly without multiplying the frequency of an output high-frequency signal, so that a device that requires low phase noise, for example, This is effective for remote keyless entry systems, RF wireless devices such as spread spectrum communication and software defined radio.
尚、本発明の各部構成は上記実施の形態に限らず、特許請求の範囲に記載の技術的範囲内で種々の変形が可能である。例えば、共振子(5)の材料として、ヤング率の高い材料、例えばダイアモンド等を用いることによって、更に高い発振周波数を実現することも可能である。又、上記実施例では電極の形状は何れも櫛歯状を呈しているが、複数の電極突出部(電極片)を互いに導電線路で接続した構成を採用することも可能である。 In addition, each part structure of this invention is not restricted to the said embodiment, A various deformation | transformation is possible within the technical scope as described in a claim. For example, it is possible to realize a higher oscillation frequency by using a material having a high Young's modulus, such as diamond, as the material of the resonator (5). In the above-described embodiments, the electrodes have a comb-like shape, but it is also possible to adopt a configuration in which a plurality of electrode protrusions (electrode pieces) are connected to each other by a conductive line.
(1) 駆動電極
(10) 電極突出部
(2) 駆動電極
(20) 電極突出部
(3) アンカー
(4) バイアス電極
(5) 共振子
(50) 支持部
(51) 支持ビーム
(52) 共振ビーム
(53) 非くびれ部
(54) くびれ部
(6) 高周波電源
(7) 主電圧電源
(8) バイアス電圧電源
(9) 基板
(1) Driving electrode
(10) Electrode protrusion
(2) Driving electrode
(20) Electrode protrusion
(3) Anchor
(4) Bias electrode
(5) Resonator
(50) Support part
(51) Support beam
(52) Resonant beam
(53) Non-constricted part
(54) Constriction
(6) High frequency power supply
(7) Main voltage power supply
(8) Bias voltage power supply
(9) Board
Claims (6)
されると共に、他方の電極(2)と共振ビーム(52)とが互いに対向して、1或いは複数のギャップ部が形成され、高周波信号の入力により何れか一方若しくは両方の電極(1)(2)と共振ビーム(52)との間に交番静電気力を発生させて共振ビーム(52)に振動を与え、何れか一方若しくは両方の電極(1)(2)と共振ビーム(52)との間の静電容量の変化を高周波信号として出力するマイクロメカニカル共振器において、共振ビーム(52)の各ギャップ部に面する領域に作用させるべき交番静電気力の領域間の比率は、各領域に一定の静電気力を作用させた場合において共振ビーム(52)の各領域の静的変位量が均等となるときの静電気力の領域間比率と同一、若しくは略同一となる様、調整されていることを特徴とするマイクロメカニカル共振器。 A resonant beam (52) having both ends supported on a substrate (9), and two electrodes (1) and (2) arranged opposite to the shaft between the both ends of the resonant beam (52). In addition, between the both ends of the resonant beam (52), one electrode (1) and the resonant beam (52) face each other to form one or a plurality of gaps, and the other electrode (2 ) And the resonant beam (52) are opposed to each other to form one or a plurality of gaps, and either or both of the electrodes (1) (2) and the resonant beam (52) are input by the input of a high frequency signal. An alternating electrostatic force is generated between them to vibrate the resonant beam (52), and the change in electrostatic capacitance between one or both of the electrodes (1), (2) and the resonant beam (52) is a high-frequency signal. In the micromechanical resonator that outputs as an alternating electrostatic force region to be applied to the region facing each gap part of the resonant beam (52) Rate becomes identical, or substantially the same as the area between the ratio of the electrostatic force when the static displacement of each region is equal to the resonant beam (52) when allowed to act constant electrostatic force in each area like A micromechanical resonator characterized by being adjusted.
6. The resonance beam (52) according to any one of claims 1 to 5, wherein a constricted portion (54) having a smaller cross-sectional area than each other region is recessed in each of a plurality of regions serving as vibration nodes. The micromechanical resonator as described.
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2006279356A JP4965962B2 (en) | 2006-10-13 | 2006-10-13 | Micromechanical resonator |
PCT/JP2007/069801 WO2008044720A1 (en) | 2006-10-13 | 2007-10-11 | Micromechanical resonator |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2006279356A JP4965962B2 (en) | 2006-10-13 | 2006-10-13 | Micromechanical resonator |
Publications (2)
Publication Number | Publication Date |
---|---|
JP2008099042A JP2008099042A (en) | 2008-04-24 |
JP4965962B2 true JP4965962B2 (en) | 2012-07-04 |
Family
ID=39282910
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP2006279356A Expired - Fee Related JP4965962B2 (en) | 2006-10-13 | 2006-10-13 | Micromechanical resonator |
Country Status (2)
Country | Link |
---|---|
JP (1) | JP4965962B2 (en) |
WO (1) | WO2008044720A1 (en) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP5081586B2 (en) * | 2007-11-08 | 2012-11-28 | 三洋電機株式会社 | Micromechanical resonator |
JP4690436B2 (en) * | 2008-05-01 | 2011-06-01 | 株式会社半導体理工学研究センター | MEMS resonator, MEMS oscillation circuit, and MEMS device |
JP5561959B2 (en) * | 2008-06-25 | 2014-07-30 | セイコーインスツル株式会社 | Electrostatic vibrator and electronic equipment |
CN114200223A (en) * | 2021-12-07 | 2022-03-18 | 浙江大学 | One is based on 1: 3 frequency ratio nonlinear electrostatic coupling MEMS resonant type electrometer |
Family Cites Families (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5976994A (en) * | 1997-06-13 | 1999-11-02 | Regents Of The University Of Michigan | Method and system for locally annealing a microstructure formed on a substrate and device formed thereby |
JP2001082964A (en) * | 1999-07-12 | 2001-03-30 | Murata Mfg Co Ltd | Resonant element |
JP3651671B2 (en) * | 2001-08-30 | 2005-05-25 | 株式会社東芝 | Micromechanical switch and manufacturing method thereof |
JP4121502B2 (en) * | 2002-10-03 | 2008-07-23 | シャープ株式会社 | Micro resonance device, micro filter device, micro oscillator, and wireless communication device |
JP4040475B2 (en) * | 2003-01-14 | 2008-01-30 | 株式会社東芝 | Micromechanical filter and portable information terminal |
JP4513366B2 (en) * | 2003-03-25 | 2010-07-28 | パナソニック株式会社 | Mechanical resonators, filters and electrical circuits |
JP2005167546A (en) * | 2003-12-02 | 2005-06-23 | Matsushita Electric Ind Co Ltd | Electromechanical filter |
JP2006222562A (en) * | 2005-02-08 | 2006-08-24 | Sony Corp | Minute resonator, band-pass filter, semiconductor device, and communications apparatus |
JP4645227B2 (en) * | 2005-02-28 | 2011-03-09 | セイコーエプソン株式会社 | Vibrator structure and manufacturing method thereof |
-
2006
- 2006-10-13 JP JP2006279356A patent/JP4965962B2/en not_active Expired - Fee Related
-
2007
- 2007-10-11 WO PCT/JP2007/069801 patent/WO2008044720A1/en active Application Filing
Also Published As
Publication number | Publication date |
---|---|
WO2008044720A1 (en) | 2008-04-17 |
JP2008099042A (en) | 2008-04-24 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP4977431B2 (en) | Micromechanical resonator | |
US7902942B2 (en) | Resonator and filter using the same | |
JP4690436B2 (en) | MEMS resonator, MEMS oscillation circuit, and MEMS device | |
KR20050101313A (en) | Micromechanical resonator device and method of making a micromechanical device | |
JP4087790B2 (en) | Micro-bridge structure with reduced central mass for very high frequency MEM resonators | |
JP6615191B2 (en) | Temperature compensated composite resonator | |
Chen et al. | A Novel Lamé Mode RF-MEMS resonator with high quality factor | |
TWI848234B (en) | Mems device | |
KR101534351B1 (en) | Coupled mems structure for motion amplification | |
JP4965962B2 (en) | Micromechanical resonator | |
JP2008103777A (en) | Micromechanical resonator | |
JP4760384B2 (en) | MEMS vibrator | |
JP2008259100A (en) | Micromechanical resonator | |
US20110068834A1 (en) | Electro-mechanical oscillating devices and associated methods | |
JP5081586B2 (en) | Micromechanical resonator | |
JP7453147B2 (en) | Configuration of MEMS resonator | |
JP2009147878A (en) | Variable filter | |
JP2008263493A (en) | Micromechanical resonator | |
JP5064155B2 (en) | Oscillator | |
Okada et al. | Silicon beam resonator utilizing the third-order bending mode | |
JP2010540266A (en) | Nanoscale or microscale vibratory electromechanical components with improved detection levels | |
JP2009171483A (en) | Electrostatic vibrator and oscillator | |
JP2009118331A (en) | Electric machine filter | |
Dong et al. | Anchor loss variation in MEMS Wine-Glass mode disk resonators due to fluctuating fabrication process | |
JP4930769B2 (en) | Oscillator |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20090909 |
|
A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20111213 |
|
A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20120203 |
|
TRDD | Decision of grant or rejection written | ||
A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20120306 |
|
A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 |
|
A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20120330 |
|
R150 | Certificate of patent or registration of utility model |
Ref document number: 4965962 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20150406 Year of fee payment: 3 |
|
S111 | Request for change of ownership or part of ownership |
Free format text: JAPANESE INTERMEDIATE CODE: R313117 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20150406 Year of fee payment: 3 |
|
R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
S531 | Written request for registration of change of domicile |
Free format text: JAPANESE INTERMEDIATE CODE: R313532 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20150406 Year of fee payment: 3 |
|
R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
LAPS | Cancellation because of no payment of annual fees |