CN105371832A - Disc multi-ring inner double-beam isolated ring resonator gyro and preparation method thereof - Google Patents

Abstract

The invention provides a double-beam isolated circular ring resonator in a disc multi-ring and a preparation method thereof. A circular ring and a plurality of concentric circular rings, wherein: the central cylinder is connected with the base, the concentric circular rings are connected by a plurality of spokes, and the two ends of the multiple double-beam isolated circular rings are respectively connected with the central cylinder and the concentric circular rings The inner side of the smallest ring is connected; a group of electrodes distributed on the peripheral edge of the double-beam isolated ring resonator in the multi-ring of the disk, and each electrode is connected to the base respectively. The invention has the advantages of small size, stable structure, sensitive response, etc., and has good symmetry, so it can achieve higher performance.

Description

A double-beam isolated circular ring resonant gyroscope in a disc multi-ring and its preparation method

technical field

The invention relates to a gyroscope in the field of micro-electromechanical technology, in particular to a double-beam isolated circular ring resonant gyroscope in a disc multi-ring and a preparation method thereof.

Background technique

Gyroscope is an inertial device that can sensitively detect the angle or angular velocity of the carrier, and plays a very important role in the fields of attitude control, navigation and positioning. With the development of national defense technology and aviation and aerospace industries, the requirements of inertial navigation systems for gyroscopes are also developing in the direction of low cost, small size, high precision, multi-axis detection, high reliability, and adaptability to various harsh environments. The micro gyroscope based on MEMS technology is processed by micro-nano batch manufacturing technology, its cost, size, and power consumption are very low, and its environmental adaptability, working life, reliability, and integration are greatly improved compared with traditional technologies. Therefore, MEMS-level micro-gyroscopes have become an important direction in the extensive research and application development of MEMS technology in recent years.

With the application and development of MEMS gyroscopes in navigation systems, the hemispherical resonant gyroscope developed by foreign scientists in 1994 has higher performance. With the help of the study of this hemispherical resonator gyroscope, the researchers have a better understanding of the design of MEMS resonators with high Q value and symmetrical structure. However, since the rod part of the early rod-structure resonators needs to be assembled on the micromechanical mechanism, higher dynamic loads and imprecise connections at the joints will lead to larger deflection of the hemispherical resonator in the long run. Therefore, I thought of designing a MEMS gyroscope with good symmetry, small and compact planar structure, that is, double-beam isolated circular ring resonant gyroscope in a disc multi-ring.

Contents of the invention

The purpose of the present invention is to provide a double-beam isolated circular ring resonant gyroscope in a disc multi-ring and its preparation method, which has the advantages of small size, stable structure, sensitive response, etc., and has good symmetry, so it can achieve higher performance .

According to one aspect of the present invention, there is provided a double-beam isolated circular ring resonant gyroscope in a disc multi-ring, including:

a base;

A double-beam isolated ring resonator in a disk multi-ring, including a central cylinder, multiple double-beam isolated rings, and multiple concentric rings, wherein: the central cylinder is connected to the base, and the concentric rings are connected by multiple spokes , both ends of multiple double-beam isolated rings are respectively connected to the inner side of the smallest ring among the central cylinder and the concentric rings;

A group of electrodes distributed on the peripheral edge of the double-beam isolated circular ring resonator in the disk multi-ring, and each electrode is connected to the base respectively.

Preferably, a protruding part is provided on the base, and the protruding part includes a central cylinder and n discrete fan ring parts on the peripheral edge, n≥8 and n is an even number, wherein: the central cylinder and n peripheral The heights of the fan ring parts with discrete edges are all equal; the n peripheral edge discrete fan ring parts are equally spaced and the width of each fan ring part is equal;

The outermost peripheral edge on the substrate is n electrode sheets distributed at equal intervals, wherein: the n electrode sheets correspond to the positions of the discrete fan ring parts of the n peripheral edges respectively, and the n electrode sheets correspond to the n discrete fan ring parts of the peripheral edges respectively. The fan ring parts are connected by wires, and the distances between the n electrode pieces and the n discrete fan ring parts on the outer edge are equal; the width and thickness of each electrode piece are equal;

A lead wire will be drawn from the central cylinder on the base for grounding or zero potential.

More preferably, a layer of conductive thin film is distributed on the central cylinder and the n discrete fan ring parts on the peripheral edge, and then the substrate is bonded to the single crystal silicon wafer.

Preferably, the material of the substrate is fused silica or heat-resistant glass or single crystal silicon.

Preferably, in the double-beam isolated circular ring resonator in the disc multi-ring: the central cylinder is located at the center of the double-beam isolated circular ring resonator in the disc multi-ring;

The central axes of the plurality of concentric rings coincide with the central axis of the central cylinder; the widths of the plurality of concentric rings are all equal; the gap widths between the concentric rings are all equal;

Each set of spokes between the concentric rings is evenly spaced; the number of each set of spokes is m, m≥8 and m is an even number; the interval angle of each set of spokes is 360°/m; the width of each spoke is equal;

In order to improve the sensitivity of the disc multi-ring resonator, multiple double-beam isolated rings are added between the central cylinder and the smallest ring among the multiple concentric rings, and the number of the double-beam isolated rings is n, n ≥8 and n is an even number, n double-beam isolated rings are equally spaced, and the centers of n double-beam isolated rings are located on the same circumference; n double-beam isolated rings are located on the same horizontal plane as the central cylinder.

More preferably, each of the double-beam isolated circular rings is centrally symmetrical, and is composed of two flexible beams and a circular ring, wherein:

The dimensions of the two flexible beams are the same, and the length and width are equal;

The diameter of the outer circle and the diameter of the inner circle of the ring are equal.

Preferably, the material of the double-beam isolated ring resonator in the disc multi-ring is single crystal silicon.

Preferably, the electrodes are n fan-shaped electrodes, n≥8 and n is an even number; the positions of the n electrodes correspond to the positions of the n double-beam isolated rings one by one, and the central axis of each electrode is It coincides with the central axis of the double-beam isolated ring resonator in the disc multi-ring; the gap distance between the n electrodes and the largest ring in the concentric ring is equal;

The n electrodes include n/2 driving electrodes and n/2 detecting electrodes, and the n/2 driving electrodes and n/2 detecting electrodes are evenly spaced along the outer edge of the double-beam isolated circular ring resonator in the disc multi-ring .

Preferably, the material of the electrodes is single crystal silicon.

According to another aspect of the present invention, a method for preparing a double-beam isolated circular ring resonant gyroscope in a disc multi-ring is provided, the method includes the following steps:

(1) Using MEMS microfabrication technology, the substrate is etched to form grooves and protruding parts, and a conductive film is plated on the protruding parts;

(2) Using bonding technology, the substrate obtained in step (1) is bonded to the monocrystalline silicon wafer;

(3) Using Deep Reactive Ion Etching (DeepReactiveIonEtching) method to etch the single crystal silicon wafer to obtain the double-beam isolated circular ring resonator in the multi-ring of the disc and the electrodes on the peripheral edge, and finally obtain the inner ring of the disc multi-ring Double beam isolated ring resonant gyroscope.

Compared with the prior art, the present invention has the following advantages:

1. The processing steps are simple, using mature micro-machining technology and etching methods, which is conducive to mass production;

2. The double-beam isolated circular ring resonant gyroscope in the disc multi-ring has a high degree of symmetry, and the structure is relatively stable, impact-resistant, and has excellent performance;

3. The electrodes distributed on the peripheral edge of the double-beam isolated ring resonator in the disk multi-ring can improve the disc The Q value of the double-beam isolated circular ring resonant gyroscope in the multi-ring, so the response is more sensitive.

The invention has the advantages of small size, stable structure, sensitive response, etc., and has good symmetry, so it can achieve higher performance.

Description of drawings

Other characteristics, objects and advantages of the present invention will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings:

FIG. 1A is a top view of a double-beam isolated circular ring resonator gyroscope in a disc multi-ring in an embodiment of the present invention;

Fig. 1B is a three-dimensional view of a double-beam isolated circular ring resonant gyroscope in a disc multi-ring in an embodiment of the present invention;

Figure 1C is a cross-sectional view of a double-beam isolated circular ring resonant gyroscope in a disc multi-ring in an embodiment of the present invention;

Figure 2A is a top view of a substrate in an embodiment of the present invention;

Figure 2B is a three-dimensional view of the substrate in one embodiment of the present invention;

Figure 2C is a cross-sectional view of a substrate in an embodiment of the present invention;

3A is a top view of a double-beam isolated circular ring resonator in a disc multi-ring in an embodiment of the present invention;

Fig. 3B is a three-dimensional view of a double-beam isolated circular ring resonator in a disc multi-ring in an embodiment of the present invention;

3C is a front view of a double-beam isolated circular ring resonator in a disc multi-ring in an embodiment of the present invention;

4A is a top view of the relative positions of the double-beam isolated circular ring resonator and its peripheral edge electrodes in the multi-ring of the disk in an embodiment of the present invention;

4B is a three-dimensional view of the relative positions of the double-beam isolated circular ring resonator and its peripheral edge electrodes in the multi-ring of the disk in an embodiment of the present invention;

4C is a cross-sectional view of the relative positions of the double-beam isolated circular ring resonator and its peripheral edge electrodes in the multi-ring of the disk in an embodiment of the present invention;

Fig. 5A is the drive mode diagram of the four-antinode vibration of the double-beam isolated circular ring resonator in the disk multi-ring when the double-beam isolated circular-ring resonator in the disk multi-ring works;

Fig. 5B is the detection mode shape diagram of four antinode vibrations done by the double-beam isolated circular ring resonator in the disc multi-ring when the double-beam isolated circular ring resonator in the disc multi-ring is working;

6A-6C are schematic diagrams of the manufacturing process flow of the substrate in an embodiment of the present invention;

Fig. 7A is a schematic diagram before the substrate and the single crystal silicon wafer are bonded in an embodiment of the present invention;

Fig. 7B is a schematic diagram of the bonding of the substrate and the single crystal silicon wafer in an embodiment of the present invention;

Fig. 8 shows that in an embodiment of the present invention, a deep reactive ion etching (DeepReactiveIonEtching) method is used to etch a single crystal silicon wafer, and finally a double-beam isolated circular ring resonant gyroscope in a multi-ring disc is obtained;

In the figure: a substrate 100 , a double-beam isolated ring resonator 102 in a disk multi-ring, and an electrode 104 .

detailed description

The present invention will be described in detail below in conjunction with specific embodiments. The following examples will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

As shown in Fig. 1A, Fig. 1B, and Fig. 1C, this embodiment provides a double-beam isolated circular ring resonant gyroscope in a disc multi-ring, including:

A base 100, comprising a central cylinder, 8 protruding fan ring parts on the secondary periphery, and 8 electrode sheets on the outermost periphery;

A double-beam isolated ring resonator 102 in a disk multi-ring, including a central cylinder, 8 double-beam isolated rings and multiple concentric rings, wherein: the central cylinder is connected to the base, and the concentric rings are connected by multiple The spokes are connected, and the two ends of the 8 double-beam isolated rings are respectively connected to the inner side of the smallest ring among the central cylinder and the concentric rings;

Eight electrodes 104 are distributed on the peripheral edge of the double-beam isolated circular ring resonator 102 in the disk multi-ring, and each electrode 104 is connected to the substrate 100 respectively.

Descriptions about length, width, height, etc. involved in the embodiments are as follows:

As shown in FIG. 2A , the center of the base 100 is a central cylinder with a bottom circle diameter of D ₁ (the value of D ₁ is 20 μm to 2 mm), and the widths of the eight fan ring parts on the second periphery are all W ₂ (W ₂ The value of 10μm～50μm), the width of the outermost 8 electrode pieces is W ₃ (the value of W ₃ is 10μm～100μm), the distance between the electrode piece and the fan ring is W ₄ (the value of W ₄ 10 μm to 100 μm).

As shown in FIG. 2C , the height of the protruding parts of the base 100 (that is, the central cylinder and the eight discrete sector ring parts on the peripheral edges) is H1 ₍ the value of H1 is ₁ μm to 100 μm), and the height of the protruding Deposit a layer of conductive film on the part, the thickness of the conductive film is H ₂ (the value of H ₂ is 100nm~1μm), and the thickness of the outermost 8 electrode sheets is H ₃ (the value of H ₃ is 100nm~1μm).

As shown in Figure 3A, the center of the double-beam isolated ring resonator 102 in the multi-ring of the disk is a central cylinder with a diameter of D2 (the value of D2 is ₂₀ μm ~ _2mm ); the width of each concentric ring is equal to W ₅ (the value of W ₅ is 5 μm to 50 μm); the width of the gap between concentric rings is W ₆ (the value of W ₆ is 5 μm to 50 μm); the width of each spoke is W ₇ (the value of W ₇ value of 5 μm to 50 μm); each double-beam isolated ring is centrally symmetrical, and is composed of two flexible beams and a ring, and the two flexible beams have the same size and the length is W ₈ (the value of W ₈ 10μm-100μm), the width is W ₉ (the value of W ₉ is 5μm-50μm), the outer diameter of the ring is D ₃ (the value of D ₃ is 10μm-100μm), and the inner diameter is D ₄ ( _The value of D4 is 10 μm to 100 μm).

As shown in FIG. 4A, the width of the eight electrodes 104 is W ₁ (the value of W ₁ is 10 μm to 50 μm), and the gap distance between each electrode 104 and the largest ring in the concentric rings is W ₁₀ ( The value of W ₁₀ is 5 μm to 50 μm).

As shown in Figures 2A, 2B, and 2C, in this embodiment, the eight discrete fan rings on the peripheral edge of the base 100 are equally spaced and each fan ring has the same width W ₂ , and the protruding center of the base 100 The height H1 _of the cylinder and the discrete fan ring parts of the eight peripheral edges is the same, the thickness _H2 of a layer of conductive film deposited on the protruding part is also the same, and the thickness H3 _of the eight electrode sheets on the outermost peripheral edge is also the same.

As shown in Figures 3A, 3B, and 3C, in this embodiment, the center of the double-beam isolated circular ring resonator 102 in the disc multi-ring is a cylindrical structure, and surrounding the central cylinder is a plurality of concentric rings and 8 double-beam isolated rings, wherein: the width W ₅ of each concentric ring is the same, and the gap width W ₆ between the concentric rings is the same; 8 spokes are evenly arranged between each concentric ring, and each spoke The width W ₇ is the same; the length W ₈ and width W ₉ of the two flexible beams in each double-beam isolated ring are the same, the outer diameter D ₃ of the ring is the same, and the inner diameter D ₄ is the same.

As shown in Figures 4A, 4B, and 4C, in this embodiment, the eight electrodes 104 are evenly distributed along the outer edge of the double-beam isolated circular ring resonator 102 in the disc multi-ring, and the central axis of each electrode 104 is in line with the The central axes of the double-beam isolated ring resonators 102 in the disc multi-ring coincide, the width W ₁ of each electrode 104 is the same, and the gap distance W ₁₀ between each electrode 104 and the largest ring in the concentric rings is also the same.

In this embodiment, in the double-beam isolated ring resonator 102 in the disc multi-ring: the width of each concentric ring is W ₅ , the width of the gap between the concentric rings is W ₆ , and the width of each spoke is W ₇ , the angle difference θ between the spokes, and the length W ₈ and width W ₉ of the two flexible beams in each double-beam isolated ring, as well as the outer diameter D ₃ and inner diameter D ₄ of the ring, can be processed Appropriate adjustments are made to achieve the desired modal match.

In this embodiment, the electrodes 104 on the peripheral edge of the double-beam isolated circular ring resonator 102 in the multi-ring of the disk are 8 sector ring electrodes, which are respectively 4 driving electrodes and 4 detecting electrodes; wherein: 4 driving electrodes and the four detection electrodes are evenly spaced, the positions of adjacent drive electrodes are spaced at 90°, the positions of adjacent detection electrodes are spaced at 90°, and the positions of adjacent drive electrodes and detection electrodes are spaced at 45°.

As shown in Figures 5A and 5B, in this embodiment, the plane four-antinode vibration mode of the double-beam isolated circular ring resonator 102 in the disc multi-ring is used as a reference vibration, and the disc multi-ring The double-beam isolated circular ring resonator 102 in the ring vibrates radially. The specific working principle is:

The double-beam isolated circular ring resonator 102 in the disc multi-ring is grounded with the central cylinder of the base 100 to ensure that the same potential is 0V; The antinode vibration mode is used as a reference vibration. When the driving electrode in the electrode 104 is applied with an AC voltage, radial vibration is generated by the inverse piezoelectric effect, thereby driving the double-beam isolated circular ring resonator 102 in the multi-ring of the disk. Vibration; when there is an angular velocity input in the direction of the central axis of the double-beam isolated circular ring resonator 102 in the multi-ring of the disk, under the action of the Coriolis force, the double-beam isolated circular ring resonator 102 in the multi-ring of the disk The vibration mode changes to the detection mode, driving the electrode 104 to vibrate, and the electric signal is obtained on the detection electrode in the electrode 104 by the positive piezoelectric effect, thereby obtaining the double-beam isolated circular ring resonance in the multi-ring of the disc The amplitude of the detector 102 in the detection mode, since the resonance amplitude of the detection mode is proportional to the magnitude of the input angular velocity, and thus the magnitude of the input angular velocity can be obtained. The driving mode and detection mode of Fig. 5A, 5B are different by 45°.

In this embodiment, the substrate 100 has a thickness of 300 μm to 800 μm and a diameter of 2 mm to 8 mm; the material of the substrate 100 is fused silica, and the quartz material has characteristics such as high temperature resistance, small thermal expansion coefficient, corrosion resistance, and resonance, and can be So that the finished gyroscope can work in harsh environments.

In this embodiment, the thickness of the double-beam isolated circular ring resonator 102 in the disk multi-ring is 100 μm-500 μm, and the diameter is 2 mm-8 mm; the thickness of the electrode 104 is 100 μm-500 μm; the disk multi-ring The materials of the inner double-beam isolated ring resonator 102 and the electrodes 104 on the peripheral edge are all monocrystalline silicon, which has semiconductor properties, which can make the gyroscope achieve higher performance.

This embodiment provides a method for preparing a double-beam isolated circular ring resonant gyroscope in a disc multi-ring, including the following steps:

(1) Using MEMS microfabrication technology, wet or dry etching is carried out on the fused silica block to obtain the groove and the protruding part of the substrate 100, and then deposit a layer of conductive film on the protruding part on the substrate , and finally obtain the substrate 100 (as shown in Figures 6A, 6B, and 6C);

(2) Using bonding technology, the substrate 100 is bonded to the single crystal silicon wafer (as shown in FIGS. Schematic diagram of single crystal silicon wafer after bonding):

(3) Using Deep Reactive Ion Etching (DeepReactiveIonEtching) method, the monocrystalline silicon wafer is etched to obtain the double-beam isolated circular ring resonator 102 in the disc multi-ring and the electrodes 104 on the peripheral edge, and finally the disc multi-ring is obtained. Double-beam isolated circular resonant gyroscope in the ring (as shown in Fig. 8).

The advantages of the gyroscope in this embodiment: 1. Smaller size; 2. Good performance; 3. Good impact resistance; 4. Simple process steps, which is conducive to mass production, thereby reducing manufacturing costs.

Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art may make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention.

Claims (10)

1. in the many rings of disk, twin beams isolates an annulus resonant gyroscope, it is characterized in that, comprising:

A substrate;

In a many ring of disk, twin beams isolates annulus resonator, comprise central cylindrical, multiple twin beams isolates annulus and multiple donut, wherein: central cylindrical is connected with described substrate, be connected by multiple spoke between donut, the two ends that multiple twin beams isolates annulus are connected with inside central cylindrical and minimum annulus in donut respectively;

One group is distributed in twin beams in the many rings of described disk and isolates the electrode of annulus resonator peripheral edge, and each electrode is connected with described substrate respectively.

2. in the many rings of a kind of disk according to claim 1, twin beams isolates annulus resonant gyroscope, it is characterized in that, described substrate is provided with the part of protrusion, the part of described protrusion comprises central cylindrical and the discrete fan loop section of n peripheral edge, n >=8 and n is even number, wherein: the height of central cylindrical and the discrete fan loop section of n peripheral edge is all equal; The discrete fan loop section of n peripheral edge equidistantly distributes and each fan loop section wide all equal;

In substrate, outermost peripheral edge is n the electrode slice equidistantly distributed, wherein: the position one_to_one corresponding of the fan loop section that n electrode slice is discrete with n peripheral edge respectively, discrete with n peripheral edge respectively fan loop section wire of n electrode slice is connected, and distance between discrete with n peripheral edge respectively fan loop section of n electrode slice is all equal; Width, the thickness of each electrode slice are all equal;

By extraction one lead-in wire on suprabasil central cylindrical, for ground connection or connecting to neutral electromotive force.

3. in the many rings of a kind of disk according to claim 2, twin beams isolates annulus resonant gyroscope, it is characterized in that, layer of conductive film is distributed with, then by described substrate and monocrystalline silicon piece bonding on described central cylindrical and the discrete fan loop section of n peripheral edge.

4. in the many rings of a kind of disk according to claim 1, twin beams isolates annulus resonant gyroscope, it is characterized in that, the material of described substrate is fused quartz or pyroceram or monocrystalline silicon.

5. in the many rings of a kind of disk according to claim 1, twin beams isolates annulus resonant gyroscope, and it is characterized in that, in the many rings of described disk, twin beams isolates in annulus resonator: central cylindrical is positioned at the center that the many ring twin beams of disk isolate annulus resonator;

The central shaft of multiple donut all overlaps with the central shaft of central cylindrical; The width of multiple donut is all equal; Relief width between donut is all equal;

Often group spoke uniform intervals arrangement between donut; The number often organizing spoke is m, m >=8 and m is even number; The interval angles often organizing spoke is 360 °/m; The width of each spoke is all equal;

The number that twin beams isolates annulus is n, n >=8 and n is even number, and n twin beams isolates annulus and equidistantly distribute, and n twin beams to isolate being centrally located at of annulus circumferentially same; N twin beams isolates annulus and central cylindrical is positioned at same level.

6. in the many rings of a kind of disk according to claim 5, twin beams isolates annulus resonant gyroscope, and it is characterized in that, each described twin beams isolates annulus and is all centrosymmetric, and forms by two flexible beams and an annulus, wherein:

Two flexible beams measure-alike, length, width are all equal;

The outside diameter of annulus, interior circular diameter homogeneous phase etc.

7. in the many rings of a kind of disk according to any one of claim 1-6, twin beams isolates annulus resonant gyroscope, it is characterized in that, in the many rings of described disk, twin beams isolates the material of annulus resonator is monocrystalline silicon.

8. in the many rings of a kind of disk according to any one of claim 1-6, twin beams isolates annulus resonant gyroscope, it is characterized in that, described electrode is n the annular electrode of fan, n >=8 and n is even number; The position of n electrode and n twin beams isolate the position one_to_one corresponding of annulus, and the central shaft that in all many with the disk rings of the central shaft of each electrode, twin beams isolates annulus resonator overlaps; N electrode is all equal with the clearance distance between annulus maximum in donut;

N electrode comprises n/2 drive electrode and n/2 detecting electrode, and n/2 drive electrode and n/2 detecting electrode isolate the arrangement of annulus resonator peripheral edge uniform intervals along twin beams in the many rings of disk.

9. in the many rings of a kind of disk according to claim 8, twin beams isolates annulus resonant gyroscope, it is characterized in that, the material of described electrode is monocrystalline silicon.

10. in the many rings of the disk described in any one of claim 1-9, twin beams isolates a preparation method for annulus resonant gyroscope, and described method comprises the steps:

(1) adopt MEMS fine process, substrate is etched, form groove and projection, projection plates layer of conductive film;

(2) bonding techniques is adopted, by the substrate of step (1) gained and monocrystalline silicon piece bonding;

(3) adopt deep reaction ion etching method, monocrystalline silicon piece is etched, obtains twin beams in the many rings of disk and isolate the electrode of annulus resonator and peripheral edge thereof, finally obtain twin beams in the many rings of disk and isolate annulus resonant gyroscope.