JP2006303558A - Mems resonator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a MEMS (Micro Elecrtro Mechanical System) resonator adopting a simple structure for forming a vibrator support beam at both side faces of a vibrator and realizing vibration for a high frequency band. <P>SOLUTION: The MEMS resonator 10 includes: the disk-shaped vibrator 20; a pair of vibration electrodes 30 arranged opposite to each other to both sides of the vibrator 20 at an air gap 35 with respect to an outer circumferential part of the vibrator 20; a pair of vibrator support beams 21 extended between both the side faces of the vibrator 20 and a pair of the vibration electrodes 30; a feeding circuit 40 for applying AC powers in phase to each other to a pair of the vibration electrodes 30; and an output circuit 20 for providing an output corresponding to the static capacitance caused between the vibrator 20 and a pair of the vibration electrodes 30, and a desired frequency is obtained by selectively setting a diameter of the vibrator 20 and a width of each of the vibrator support beams 21. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a MEMS resonator, and more particularly to a vibrating body support structure for a disk-shaped vibrating body of a MEMS resonator.

  In recent years, with the advent of the world's advanced information society, the communication and multimedia markets have undergone tremendous development, such as the spread of personal use mobile phones and the birth of new businesses using the Internet. Therefore, a communication field, particularly a mobile phone, is a field in which MEMS (Micro Electro Mechanical System) is attracting attention. Passive components such as an antenna changeover switch and a band changeover switch increase due to the progress of multiband use using Bluetooth and wireless LAN. In order to promote downsizing and low power consumption, it is effective to make these components into one chip and shorten the wiring distance. Also, since the MEMS element operates mechanically, it is affected by signal noise. Performance is expected to decrease.

  Conventionally, a high-frequency element using MEMS technology has a MEMS resonator that excites mechanical vibration of a vibrating body by electrostatic force based on AC power and detects a change in capacitance caused by the mechanical vibration of the vibrating body. is there. However, high frequency is required for the applications as described above. In order to increase the frequency of a MEMS resonator, a structure using expansion / contraction vibration from a conventionally employed bending vibration (beam shape or the like) has been adopted.

  As one of the structures that use expansion and contraction vibration, a disk-center support structure is known in which a support part is formed at the center of a disk-shaped vibration body and the vibration body expands and contracts in the radial direction to realize high-frequency band vibration. (For example, refer to Patent Document 1).

  As another example of a structure using expansion and contraction vibration, a disk that realizes vibration in a high frequency band by forming vibration body support beams on both side surfaces of a disk-shaped vibration body and expanding and contracting the vibration body in the radial direction. -Side support structure is known (for example, refer nonpatent literature 1).

  Further, as a conventional structure, a simple beam structure is known in which a beam is bent or stretched and contracted to obtain a high frequency band vibration (see, for example, Non-Patent Document 2).

US Pat. No. 6,628,177 Mohamed A. Abedelmonium, Jing Wang, Mustafa U. Demirci, Clark T .; C. Nguyen, “STEMLESS WIN-GLASS-MODE DISK MICROME CHANCIAL RESONATORS”, 16th Int. IEEE Micro Mechanical Systems Conf. Kyoto, Japan, Jan. 19-23, 2003, pp698-701 www. fyslab. hut. fi / kurssit / Tfy-3.480 / Spring2004 / Feb04 Mattilla / lecture04Feb2004. pdf

  In such a disk-center support structure of Patent Document 1, a support part is formed at the center part of a disk-shaped vibrating body, and the vibrating body is expanded and contracted to vibrate. In the proposed conventional structure, Although it is possible to obtain a high frequency band, it is known that a predetermined frequency cannot be obtained even with a slight shift in the alignment accuracy of the central support portion, and there is a problem that it is difficult to manufacture.

  In addition, according to the disk-side support structure of Non-Patent Document 1, since the resistance component when the characteristic of the MEMS resonator is replaced with an equivalent circuit component is low, the impedance support is easy and the vibrating body support portion is optimized. Therefore, it is generally considered more useful than the central support structure because it has the advantages that the Q value can be increased and the DC bias voltage can be suppressed low.

  In addition, the conventional simple beam structure according to Non-Patent Document 2 has an advantage of being easy to design because the structure is simple, but the frequency is lower than the structure according to Patent Document 1 or Non-Patent Document 1 described above. However, since the electrode crossing area is small, the output is small.

  From the above-mentioned patent documents and non-patent documents, it is described that the frequency becomes higher as the diameter or length of the beam is smaller (shorter) in any structure. However, these are applied only when it is assumed that there is no influence of the support part when the vibration part (disk or beam) is very large with respect to the support part. It is expected that the length becomes very short, and as a result, the influence of the connecting portion between the support portion and the vibrating portion cannot be ignored.

  The object of the present invention is to solve the above-mentioned problems, and in the structure in which the vibrating body supporting beams are formed on both side surfaces of the vibrating body, the diameter of the vibrating body, the shape of the vibrating body supporting beam and their connecting portions are set. An optimum design is to provide a MEMS resonator that realizes vibrations in a high frequency band.

  The MEMS resonator of the present invention includes a disk-shaped vibrating body, a pair of electrodes disposed on both sides of the vibrating body so as to face each other with a gap with respect to an outer peripheral portion of the vibrating body, and both side surfaces of the vibrating body. A pair of vibrating body support beams extending between the pair of electrodes, a power feeding means for applying in-phase AC power to the pair of electrodes, and between the vibrating body and the pair of electrodes Detecting means for obtaining an output corresponding to the capacitance, and selectively setting the diameter of the band vibrator and the width of the vibrator support beam to obtain a desired frequency.

  According to the present invention, the conventional disk-side support structure can be obtained by using a general semiconductor manufacturing process with a simple structure by adjusting the diameter of the vibrator and the width of the vibrator support beam to an appropriate range. It is possible to obtain vibration in a high frequency band that is difficult to be obtained.

  In the structure of the present invention, it is preferable that a distance between the pair of electrodes and the vibrating body support beam is set larger than a gap between the vibrating body and the pair of electrodes.

  Since the MEMS resonator of the present invention has a structure for detecting a change in capacitance of the gap between the vibrating body and the pair of electrodes, the distance between the vibrating body support beam and the vibrating body should be larger than the gap. Thus, it is possible to eliminate the influence on the capacitance change due to the provision of the vibrating body support beam, and to obtain a stable detection value.

  Further, according to the above-described structure, the diameter of the vibrating body is set in the range of 20 μm to 40 μm, and the width of the connecting portion of the vibrating body support beam to the vibrating body is set in the range of 0.2 μm to 5 μm. It is desirable.

  Specifically, as will be described later in the embodiment, the disk-shaped vibrating body has a region where the frequency band obtained in the range of 20 μm to 40 μm is maximized, and the width of the vibrating body supporting beam is then Since the higher the frequency, the higher the frequency, the higher the vibration in the range of 0.2 μm to 5 μm in consideration of the structural strength of the vibrating body support beam. .

Moreover, it is desirable that the vibrating body is made of a silicon layer or a silicon compound formed on a silicon substrate.
Here, the silicon substrate is, for example, a semiconductor substrate, and the silicon compound is, for example, polysilicon (Poly-Si) or silicon nitride (SiN) used in a semiconductor process.

In this way, by having the vibrating body composed of the silicon layer on the silicon substrate, the vibrating body can be easily formed by a normal silicon semiconductor manufacturing process.
In addition, by using a silicon substrate as a semiconductor substrate, a power feeding means for applying AC power for driving the vibrating body and a detection means for obtaining an output can be built in, and it can be made into one chip. There is an effect that power consumption can be reduced by shortening the wiring distance.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 5 are graphs showing the relationship between the structure of a MEMS resonator according to an embodiment of the present invention and the shape and frequency of a vibrator, and FIG. 6 is the relationship between the diameter and frequency of a disk by a central support structure according to the prior art. FIG. 7 is a graph showing the relationship between the beam length and the frequency of the simple beam structure according to the prior art.
(Embodiment)

First, in order to clarify the characteristics of the MEMS resonator of the present invention, the frequency characteristics according to the above-described prior art will be described with reference to the drawings.
FIG. 6 is a graph showing the relationship between the diameter and the frequency of the vibrating body according to the central support structure in the prior art. This structure is a structure in which the central part of the disk-shaped vibrating body is connected by a support part. In FIG. 6, the horizontal axis indicates the diameter (unit: μm) of the vibrating body (sometimes referred to as a disk), and the vertical axis indicates the frequency (unit: MHz).

As calculation conditions, the material constant is Young's modulus: 169 GPa, Poisson's ratio: 0.3, density: 2500 kg / m ³ , the diameter of the central support is 1 μm, the thickness of the vibrator is 2 μm, and the diameter of the vibrator is And the frequency relationship was calculated.

  As this graph shows, in the disc-center support structure, the frequency increases as the disc diameter decreases. In addition, there is no frequency peak region on this graph, and the diameter of the disk from which the desired frequency can be obtained is only one point.

  FIG. 7 shows a graph showing the relationship between the beam length and the frequency by the simple beam structure in the prior art. This graph shows each frequency when the length of the beam is changed in a state where the beam width is 10 μm, the thickness is 2 μm, and the support beam width is 20 μm. In FIG. 7, the horizontal axis indicates the length of the beam (unit: μm), and the vertical axis indicates the frequency (unit: MHz). The material constant is the same constant as the disk-center support structure described above.

  As shown in this graph, under the above conditions, the frequency increases as the length of the beam decreases, but it is assumed that the frequency does not increase even when the beam length is 20 μm or less, and the maximum frequency reaches 84 MHz. do not do.

Subsequently, an embodiment according to the present invention will be described with reference to the drawings.
FIG. 1 shows an example of the structure of the MEMS resonator 10 according to the present embodiment. FIG. 1 (a) is a plan view, and FIG. 1 (b) is an A-G-A in FIG. 1 (a). It is sectional drawing. 1A and 1B, the MEMS resonator 10 according to the present embodiment may be represented as a disc-shaped vibrating body 20 (a disc portion 20) formed on the surface of the silicon substrate 11 as a basic configuration. ) And a vibrating electrode 20 that surrounds the vibrating body 20 and has an air gap 35 between the outer periphery of the vibrating body 20 and a pair of excitation electrodes 30 that are formed with the vibrating body 20 interposed therebetween. Yes.

  An insulating layer 12 is formed on the surface of the silicon substrate 11, and a vibrating body 20 and a vibrating electrode 30 are formed on the upper surface thereof. The vibrating body 20 is made of a silicon compound such as a silicon layer or polysilicon, and a pair of vibrating body support beams 21 are extended from both side surfaces of the vibrating body 20.

  A support portion 22 connected to the silicon substrate 11 is formed at the end of the vibration body support beam 21, and a gap is provided between the silicon substrate 11 and the lower portion of the vibration body 20, and elastic vibration is generated in the radial direction. It is a shape that can be done. In addition, an electrode layer 23 is formed on the lower surface of the vibrating body 20 and the vibrating body support beam 21, and is connected to an output circuit 50 as detection means via an output line 51.

  The excitation electrode 30 is formed in a pair with a gap 35 having a certain distance L1 in the planar direction from the vibrating body 20, and each shape is symmetrical with the vibrating body 20 in between. The distance L2 of the gap 36 between the extended vibrating body support beam 21 and the excitation electrode 30 is set to be larger than the gap 35, and in this embodiment, L2> 3 × L1. It is preferable.

  The MEMS resonator 10 according to the present embodiment has a structure that detects and outputs a change in capacitance generated between the vibrating body 20 and the excitation electrode 30 when the vibrating body 20 expands and contracts. Is inversely proportional to the square of the distance between the vibrating body 20 and the excitation electrode 30 facing each other, and is proportional to the facing area. Therefore, by setting L2> 3 × L1, the capacitance generated in the gap 36 is Compared to the capacitance generated at 35, it is smaller by one digit or more and can be suppressed to a value that does not affect the output.

  An electrode layer 31 is also formed on the lower surface of the excitation electrode 30. The MEMS resonator 10 is provided with a power feeding circuit 40 as power feeding means for applying in-phase AC power to the pair of excitation electrodes 30. The power supply circuit 40 is provided with an AC power supply 41 and a supply line 42 that connects the AC power supply 41 and the electrode layer 31 formed on the excitation electrode 30.

  In the present embodiment, the power supply circuit 40 is monolithically configured inside the silicon substrate 11, but may be configured separately from the silicon substrate 11, or only a wiring structure for supplying AC power from the outside. May be formed.

  Further, in the present embodiment, the vibrating body support beam 21 is an output electrode, and an output circuit 50 is provided as a detecting means for outputting an output signal (detection signal) corresponding to the stretching vibration of the vibrating body 20. Yes.

  The output circuit 50 includes an inductance 52 connected between the power supply potential 53 and the output potential of the output line 51, and a load resistor 54 connected between the output potential and the ground potential. Is provided with an output terminal 55.

  In the present embodiment, the disk-shaped vibrating body 20 generates vibration in a mode in which it expands and contracts in the radial direction between the pair of excitation electrodes 30, and the distance L <b> 1 of the gap 35 changes according to the expansion and contraction vibration. By doing so, the electrostatic capacitance between the vibrating body 20 and the excitation electrode 30 increases or decreases. The increase / decrease in capacitance appears as an output current io generated in the output circuit 50, so that the output current io and the output potential Vo generated in the load resistor 54 are output to the output terminal 55. This output potential Vo has a vibration waveform corresponding to the natural vibration frequency of the vibrating body 20.

  The expansion and contraction vibration of the vibrating body 20 is a radial vibration accompanied by a shape change of the contour (outer peripheral portion) of the planar shape of the disk-shaped vibrating body 20, and the static vibration between the vibrating body 20 and the pair of excitation electrodes 30. This is due to electric power. In this vibration mode, the vibrating body 20 has a natural vibration frequency determined by its planar shape, thickness, density of constituent materials, and elastic characteristics (for example, Young's modulus, Poisson's ratio, etc.).

Next, the relationship between the natural vibration frequencies of the vibrating body 20 resulting from the shapes of the vibrating body 20 and the vibrating body support beam 21 of the MEMS resonator 10 according to the present embodiment will be described with reference to the drawings.
Note that eigenvalue analysis was performed on the basic shape shown in FIG. The material constants of the vibrator 20 used for this calculation were Young's modulus: 169 GPa, Poisson's ratio: 0.3, and density: 2500 kg / m ³ .

  FIG. 2 is a graph showing the relationship between the thickness of the disk-shaped portion of the vibrating body 20 and the frequency. Here, the diameter of the vibrating body 20 is 30 μm, and the width of the vibrating body support beam 21 is 10 μm. In FIG. 2, the horizontal axis represents the thickness of the disk portion of the vibrating body 20 (unit: μm), and the vertical axis represents the calculated frequency (unit: MHz).

  As shown in this graph, in the range where the thickness of the vibrating body 20 is 0.5 μm to 3.0 μm, the frequency is almost constant at 88 MHz, and in this thickness range, the thickness does not affect the frequency. ing. It is presumed that the thickness of the vibrating body 20 does not greatly affect the frequency even in a range of 0.5 μm or less and 3.0 μm or more, not shown.

Next, the relationship between the diameter of the vibrating body 20 and the frequency will be described with reference to the drawings.
FIG. 3 is a graph showing the relationship between the diameter and the frequency of the vibrating body 20 based on the shape according to the present embodiment. Here, the material constants are the same as those described above, and the calculation results are shown assuming that the thickness of the vibrating body 20 is 2 μm and the width of the vibrating body support beam 21 is 10 μm. In FIG. 3, the horizontal axis indicates the diameter (unit: μm) of the vibrating body 20, and the vertical axis indicates the frequency (unit: MHz).

  As shown in this graph, in the above-mentioned shape and material constant, the peak of the frequency is at the position where the diameter of the disk portion is 32 μm, and the frequency decreases even if the diameter is made smaller or larger than this. The maximum value of the frequency is 88 MHz. The calculation results shown in FIG. 3 are the results under the above-mentioned calculation conditions. Depending on these calculation conditions, the maximum frequency value and the diameter of the disk portion representing the peak value also change. It can be inferred that the diameter of the curve shows the same tendency as in the illustrated graph.

Next, the relationship between the width of the vibrating body support beam 21 and the frequency will be described with reference to the drawings.
FIG. 4 shows a graph showing the relationship between the width and the frequency of the vibrating body support beam 21 based on the shape according to the present embodiment. Here, the material constants are the same as those described above, and the calculation results are shown assuming that the thickness of the vibrating body 20 is 2 μm and the diameter of the vibrating body 20 is 30 μm. In FIG. 4, the horizontal axis represents the width (unit: μm) of the vibrator support beam, and the vertical axis represents the frequency (unit: MHz).

  As shown in this graph, the frequency increases as the width of the vibrating body support beam 21 decreases. In addition, in the range in which the width of the vibrator support beam 21 is illustrated, the frequency is 110 MHz or more, and when the width is 5 μm or more, the change in the frequency is reduced. Therefore, it is preferable that the width of the vibrating body support beam 21 for obtaining the frequency in the high frequency band in the disk-side support structure which is the object of the present invention is set in the range of 0.2 μm to 5 μm.

Here, the frequency and the shape dependence of the vibrating body according to the prior art and the present embodiment will be summarized (refer to FIGS. 1 to 4 and FIGS. 6 and 7 for comparison).
(1) According to the central support structure (see FIG. 6), it is possible to obtain vibrations in a high frequency band of 100 MHz or more by reducing the diameter of the disk portion, but there is no frequency peak region as described above. In addition, there is a problem that the shift of the center support portion position affects the vibration mode (frequency fluctuation) and is difficult to manufacture.

  (2) The simple beam structure (see FIG. 7) has the advantage that the structure is simple and easy to manufacture, but there is a problem that high frequency is difficult.

(3) According to the disk-side support structure of this embodiment (see FIGS. 1 to 4), the frequency depends on the diameter of the vibrating body and the width of the vibrating body support beam, and a high frequency band can be realized. Become.
From these facts, by designing the diameter of the vibrating body 20 and the width of the vibrating body support beam 21 optimally, it is possible to find a specification that realizes a desired high-frequency region. Therefore, a combination of optimum values of the diameter of the vibrating body 20 and the width of the vibrating body support beam 21 will be considered.

  FIG. 5 shows a graph showing the relationship among the frequency, the diameter of the vibrating body 20 and the width of the vibrating body support beam 21 according to the present embodiment. In FIG. 5, the horizontal axis indicates the width (unit: μm) of the vibrator support beam 21, the vertical axis indicates the frequency (unit: MHz), and the diameter of the vibrator 20 indicates the frequency peak of 32 μm. Is set to a range of 20 μm to 40 μm, and the relationship between each frequency and the width of the vibrating body support beam 21 is shown. The thickness of the vibrating body 20 is set to 2 μm.

  As shown in this graph, in the range where the diameter of the vibrating body 20 is 20 μm to 40 μm, the frequency increases as the width of the vibrating body support beam 21 decreases. In addition, as the width of the vibrating body support beam 21 is smaller, the frequency expression range due to the diameter of the vibrating body 20 becomes wider, and at 1 μm width, the disk diameter is about 10 MHz when the diameter is 32 μm and when the diameter is 40 μm. It shows that there is a difference.

  Further, it is presumed that the smaller the width of the vibrating body support beam 21 is, the smaller the connection area with the vibrating body 20 is. As a result, the vibration leakage to the silicon substrate 11 is reduced and the Q value is high.

  From these, the simple structure of the simple structure can be obtained by selecting the appropriate combination of the diameter of the vibrator 20 in the range of 20 μm to 40 μm and the width of the vibrator support beam in the range of 0.2 μm to 5 μm. It is possible to obtain vibration in a higher frequency band.

  Therefore, according to the above-described embodiment, by adjusting the diameter of the vibrating body 20 and the width of the vibrating body support beam 21 to an appropriate range, a conventional disk can be obtained using a general semiconductor manufacturing process with a simple structure. -It is possible to obtain vibration in a high frequency band that is difficult to obtain with the side support structure.

  Further, since the MEMS resonator 10 of the present invention has a structure for detecting a change in the capacitance of the gap 35 between the vibrating body 20 and the pair of excitation electrodes 30, the gap between the vibrating body support beam 21 and the vibrating body 20. By making the distance L2 of 36 larger than the distance L1 of the gap 35 described above, it is possible to eliminate the influence on the capacitance change due to the provision of the vibrating body support beam 21, and to obtain a stable detection output.

  In addition, since the frequency band obtained in the range of 20 μm to 40 μm in the diameter of the vibrating body 20 has a maximum region, and at that time, a higher frequency is obtained as the width of the vibrating body support beam 21 is reduced, In consideration of the structural strength of the vibrating body support beam 21, vibration in the highest high frequency region can be obtained in the range of 0.2 μm to 5 μm as this type of MEMS resonator.

  Furthermore, by forming the vibrating body 20 made of polysilicon on the silicon substrate 11, the vibrating body 20 can be easily formed by a normal silicon semiconductor manufacturing process. Further, by using the silicon substrate 11 as a semiconductor substrate, a power feeding circuit 40 for applying AC power for driving the vibrating body 20 and an output circuit 50 for outputting a detection signal can be incorporated into a single chip. There is an effect that power consumption can be reduced by downsizing and shortening the wiring distance.

It should be noted that the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.
For example, in the above-described embodiment, the power feeding circuit 40 and the output circuit 50 are configured as separate circuits, but the power feeding circuit 40 and the output circuit 50 are realized by a common circuit unit according to the mode of the vibrating body. Various configurations can be employed.

  In the above-described embodiment, the vibrating body support beam 21 extends in the same straight line with respect to the vibrating body 20, but the structure of the vibrating body support beam 21 is not necessarily formed in a straight line. Rather, it can be freely set by making the relative relationship with the excitation electrode symmetrical (meaning that the vibration mode becomes symmetrical).

In this embodiment, the material of the vibrating body 20 is exemplified as polysilicon, and the material constant is calculated with Young's modulus: 169 GPa, Poisson's ratio: 0.3, and density: 2500 kg / m ³ , but these are different. The material can be selected, and the frequency can be further increased by changing the material constant. At this time, the frequency peak is not always at the position where the diameter of the vibrating body is 32 μm.

  Therefore, according to the above-described embodiment, it is possible to provide a MEMS resonator that realizes vibration in a high frequency band with a simple structure in the structure in which the vibrating body support beams are formed on both side surfaces of the vibrating body.

  The MEMS resonator according to the present invention can be employed as a resonator or a filter in addition to a vibrator. It can also be used as an actuator driven at high frequency.

The structure of the MEMS resonator which concerns on embodiment of this invention is shown, (a) is a top view, (b) is AGA sectional drawing of Fig.1 (a). The graph which shows the relationship between the thickness of the disc part of the vibrating body which concerns on embodiment of this invention, and a frequency. The graph which shows the relationship between the diameter of the disc part of the vibrating body which concerns on embodiment of this invention, and a frequency. The graph which shows the relationship between the width | variety and frequency of a vibrating body support beam which concern on embodiment of this invention. The graph which shows the relationship between the frequency which concerns on embodiment of this invention, a disc part diameter, and the width | variety of a vibrating body support beam. The graph which shows the relationship between the diameter of the disk by the center support structure which concerns on a prior art, and a frequency. The graph which shows the relationship between the length of the beam by the simple beam structure based on a prior art, and a frequency.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... MEMS resonator, 20 ... Vibrating body, 21 ... Vibrating body support beam, 30 ... Excitation electrode, 35 ... Air gap, 40 ... Feeding circuit, 50 ... Output circuit.

Claims (4)

A disk-shaped vibrating body, and a pair of electrodes disposed opposite to each other with a gap with respect to the outer periphery of the vibrating body on both sides of the vibrating body;
A pair of vibrating body support beams extending between the pair of electrodes from both sides of the vibrating body;
Power supply means for applying in-phase AC power to the pair of electrodes;
Detection means for obtaining an output corresponding to a capacitance between the vibrating body and the pair of electrodes;
With
A MEMS resonator, wherein a desired frequency is obtained by selectively setting a diameter of the vibrator and a width of the vibrator support beam. The MEMS resonator according to claim 1,
A MEMS resonator, wherein a distance between the pair of electrodes and the vibrating body support beam is set to be larger than a gap between the vibrating body and the pair of electrodes. The MEMS resonator according to claim 1 or 2,
A MEMS resonator, wherein a diameter of the vibrating body is set in a range of 20 μm to 40 μm, and a width of a connecting portion of the vibrating body support beam to the vibrating body is set in a range of 0.2 μm to 5 μm. The MEMS resonator according to any one of claims 1 to 3,
2. The MEMS resonator according to claim 1, wherein the vibrator is made of a silicon layer or a silicon compound formed on a silicon substrate.

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