Resonator structure and sensor

Abstract

The utility model discloses a resonator structure which comprises a glass substrate, a DEFT resonant beam is arranged on the upper end face of the glass substrate, and the two ends of the DEFT resonant beam are connected with the glass substrate through heat insulation spring units. Comb tooth units are arranged on the two sides of the DEFT resonant beam; and a heat insulation layer is arranged on the DEFT resonant beam. The two ends of the DEFT resonant beam are connected with the glass substrate through the heat insulation spring units, the heat insulation spring units reduce the contact area between the connecting pieces and the glass substrate, heat insulation can be well conducted on the resonator, and when the resonator generates thermal strain, the heat insulation spring units can play a certain buffering role so as to reduce the influence of temperature on the frequency of the resonator. And the problem that the measurement precision is influenced by temperature drift generated by the MEMS silicon resonator structure under the condition that the temperature change is relatively large is avoided.

Description

TECHNICAL FIELD

[0001] The utility model belongs to MEMS resonator technical field relates to a resonator structure and sensor. BACKGROUND

[0002] MEMS silicon resonator (silicon resonator) as a frequency control element in various MEMS sensors, can ensure that the signal output by the sensor has stable frequency characteristics. When the MEMS sensor senses external physical quantities (such as pressure, temperature, acceleration, etc.), the vibration frequency of the silicon resonator will change. By measuring this frequency change, accurate measurement and signal processing of external physical quantities can be achieved.

[0003] The development of MEMS processing technology has driven the miniaturization of sensors. Although micro-machining technology can control process precision within a very small range, it is still difficult to accurately control the doping concentration of diffused silicon, which directly leads to the existence of zero temperature drift and sensitivity temperature drift. In particular, as the operating temperature range of the resonator continues to increase, temperature compensation becomes increasingly important.

[0004] The main purpose of studying the MEMS silicon resonator structure with low temperature drift is to solve the temperature drift problem caused by large temperature changes, to enable the MEMS silicon resonator to continue to work normally in a large operating temperature range, to achieve more accurate and effective measurement, and to obtain more accurate data, thereby improving the accuracy, safety and reliability of the equipment. Therefore, there is an urgent need for a method that can effectively reduce the temperature drift of the MEMS resonator. UTILITY MODEL CONTENTS

[0005] The utility model aims at solving the temperature drift problem of the MEMS silicon resonator structure in the prior art under large temperature changes, which affects the measurement accuracy, and provides a resonator structure.

[0006] To achieve the above-mentioned purpose, the utility model adopts the following technical solutions:

[0007] A resonator structure, comprising a glass substrate, a DEFT resonator beam is arranged on the upper end face of the glass substrate, and the two ends of the DEFT resonator beam are connected with the glass substrate through a heat insulation spring unit.

[0008] Comb tooth units are arranged on both sides of the DEFT resonator beam.

[0009] A heat insulation layer is arranged on the DEFT resonator beam.

[0010] Further, the further improvement of the utility model lies in, the heat insulation spring unit includes heat insulation spring, the heat insulation spring is connected with DEFT harmonic beam, and the heat insulation spring is connected glass base through anchor point.

[0011] Further, the further improvement of the utility model lies in, the side wall of heat insulation spring is connected with the end of DEFT harmonic beam;

[0012] Both ends of heat insulation spring are connected anchor point.

[0013] Further, the further improvement of the utility model lies in, the anchor point is connected with glass base through insulating silicon oxide layer.

[0014] Further, the further improvement of the utility model lies in, the heat insulation layer is SIO2 layer.

[0015] Further, the further improvement of the utility model lies in, the comb tooth unit includes oppositely arranged comb tooth moving tooth and comb tooth fixed tooth.

[0016] Further, the further improvement of the utility model lies in, the comb tooth fixed tooth includes first comb tooth fixed tooth and second comb tooth fixed tooth;

[0017] The first comb tooth fixed tooth is arranged at the side of comb tooth moving tooth away from DEFT harmonic beam,

[0018] Second comb tooth fixed tooth is arranged at the side of comb tooth moving tooth close to DEFT harmonic beam.

[0019] Further, the further improvement of the utility model lies in, the second comb tooth fixed tooth is sequentially provided with two in axial direction.

[0020] Further, the further improvement of the utility model lies in, the tooth number of second comb tooth fixed tooth is 11, and the tooth number of first comb tooth fixed tooth is 22.

[0021] A sensor, characterized in that, including the resonator structure of any one of the utility model.

[0022] Compared with the prior art, the utility model has the following beneficial effects:

[0023] The utility model discloses a resonator structure, DEFT harmonic beam both ends are connected with glass base through heat insulation spring unit, and heat insulation spring unit reduces the contact area of connecting piece and glass base, can good to the heat insulation of resonator, when resonator generates thermal strain, heat insulation spring unit can play certain buffering effect to reduce the influence of temperature on resonator frequency, avoid the temperature drift of MEMS silicon resonator structure under the condition that temperature changes greatly, influence the problem of measurement accuracy.

[0024] Further, the heat insulation layer is an SIO2 layer, a composite resonant beam is formed by covering an SIO2 layer on the surface of the resonant beam, the thermal expansion coefficients of silicon and silicon dioxide are opposite before 600 DEG C, stress opposite to the resonant beam can be generated, when the two are combined together, the expansion or contraction trend of the SIO2 can offset part of the deformation of the resonant beam, the stress change can adjust the overall rigidity of the resonant beam, so that the resonant frequency of the resonator is stabilized, and then the temperature drift phenomenon is effectively reduced. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the technical scheme of the embodiments of the present application, the drawings needed in the embodiments will be briefly introduced as follows, and it should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation on the scope, and for those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0026] Figure 1 is the overall schematic diagram of the resonator structure provided by the embodiments of the present application;

[0027] Figure 2 is the plane schematic diagram of the resonator structure provided by the embodiments of the present application;

[0028] Figure 3 is the plane structure schematic diagram of the heat insulation spring in the resonator structure provided by the embodiments of the present application;

[0029] Figure 4 is the structure schematic diagram of the second comb tooth fixed tooth provided by the embodiments of the present application;

[0030] Figure 5 is the structure schematic diagram of the first comb tooth fixed tooth provided by the embodiments of the present application;

[0031] Figure 6 is the mutual meshing diagram of the comb tooth movable tooth, the first comb tooth fixed tooth and the second comb tooth fixed tooth provided by the embodiments of the present application;

[0032] Wherein: 1-anchor point; 2-heat insulation spring; 3-DEFT resonant beam; 4-comb tooth movable tooth; 5-first comb tooth fixed tooth; 6-second comb tooth fixed tooth; 7-glass substrate. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme of the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are some embodiments of the present application, rather than all the embodiments of the present application. The components of the embodiments of the present application described and shown in the drawings can be arranged and designed in various different configurations.

[0034] Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of the present application.

[0035] It should be noted that: similar reference numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0036] In the description of the embodiments of the present application, it should be noted that if the terms "upper", "lower", "horizontal", "inner" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship of the present application product when it is usually placed, only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the indicated device or element must have a particular orientation, structure and operation, therefore cannot be understood as limiting the present application. In addition, the terms "first", "second" and the like are only used for differentiation, and cannot be understood as indicating or implying relative importance.

[0037] In addition, if the term "horizontal" appears, it does not mean that the component must be absolutely horizontal, but can be slightly inclined. For example, "horizontal" only means that its direction is relatively more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined.

[0038] In the description of the embodiments of the present application, it should also be noted that unless otherwise explicitly specified and limited, if the terms "set", "mount", "connected", "connected" appear, they should be understood in a broad sense, for example, they can be fixedly connected, or can be detachably connected, or integrally connected; can be mechanically connected, or can be electrically connected; can be directly connected, or can be indirectly connected through an intermediate medium; can be the communication inside two elements. For those of ordinary skill in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0039] The present application will be described in further detail below in conjunction with the drawings:

[0040] Referring to Figures 1 to 6 The utility model discloses a resonator structure, concretely is a novel resonator structure capable of effectively reducing resonator temperature drift.

[0041] Including following structure:

[0042] Embodiment 1

[0043] The utility model discloses a resonator structure, including glass base 7, DEFT resonator beam 3 is arranged on the upper end surface of glass base 7, and the both ends of DEFT resonator beam 3 are connected with glass base 7 through heat insulation spring unit, and the both sides of DEFT resonator beam 3 are provided with comb tooth unit, and heat insulation layer is arranged on DEFT resonator beam 3.

[0044] The utility model discloses DEFT resonator beam both ends are connected with glass base through heat insulation spring unit, and heat insulation spring unit reduces the contact area of connecting piece and glass base, can very good to the resonator is heat insulated, when resonator generates thermal strain, heat insulation spring unit can play certain buffer effect to reduce the influence of temperature on resonator frequency, avoid the temperature drift of MEMS silicon resonator structure under the condition of the temperature change of big, influence the problem of measurement accuracy.

[0045] Further, in the embodiment, glass base 7 is Pyrex7740 glass, and the thermal expansion coefficient thereof is similar to that of silicon, so that the influence of thermal stress can be reduced, the residual stress exists in the structure in the high temperature and planing process in processing, and the residual stress can be released to some extent after aging, so that the influence of thermal expansion mismatch and thermal stress caused by temperature change is effectively reduced. This design makes the sensitive part (such as the MEMS resonator) close to the free thermal expansion state when the temperature changes, reduces the measurement error caused by the temperature change, and significantly reduces the temperature drift.

[0046] Embodiment 2

[0047] The utility model discloses a resonator structure, including glass base 7, DEFT resonator beam 3 is arranged on the upper end surface of glass base 7, and the both ends of DEFT resonator beam 3 are connected with glass base 7 through heat insulation spring unit, and the both sides of DEFT resonator beam 3 are provided with comb tooth unit, and heat insulation layer is arranged on DEFT resonator beam 3, the heat insulation spring unit includes heat insulation spring 2, and the side wall of heat insulation spring 2 is connected with the end of heat insulation spring 2, and the both ends of heat insulation spring 2 are connected anchor point 1.

[0048] Specifically, four anchor points 1 are arranged on the glass base 7, and the glass base 7 and the anchor points 1 are bonded and connected through the intermediate insulating silicon oxide layer.

[0049] Specifically, the heat insulation spring 2 is distributed in four, two on the top and two on the bottom, and one end of the two heat insulation springs is connected through a cantilever beam and then connected with the end of the DEFT resonant beam 3.

[0050] The heat insulation spring structure between the anchor point and the resonant beam has a small cross section, and such a silicon structure can become a good thermal insulation structure and can act as a support device and a fixing device of the beam.

[0051] Embodiment 3

[0052] The utility model discloses a resonator structure, including glass substrate 7, DEFT resonant beam 3 is provided on the upper end surface of glass substrate 7, and the both ends of DEFT resonant beam 3 are connected with glass substrate 7 through heat insulation spring unit, and the both sides of DEFT resonant beam 3 are provided with comb tooth unit, and DEFT resonant beam 3 is provided with heat insulation layer, and the heat insulation layer is SIO2 layer, and SIO2 layer covers DEFT resonant beam.

[0053] Specifically, a layer of SIO2 is covered on the surface of the resonant beam to form a composite resonant beam, and the thermal expansion coefficients of silicon and silicon dioxide are opposite before 600 DEG C, can produce the stress that is opposite with resonant beam, when combining together, the trend that SIO2 expands or shrinks can offset part of the deformation of resonant beam, and this stress change can adjust the overall stiffness of resonant beam, thereby stabilizing the resonant frequency of resonator, and further effectively reducing the temperature drift phenomenon.

[0054] Embodiment 4

[0055] The utility model discloses a resonator structure, including glass substrate 7, DEFT resonant beam 3 is provided on the upper end surface of glass substrate 7, and the both ends of DEFT resonant beam 3 are connected with glass substrate 7 through heat insulation spring unit, and the both sides of DEFT resonant beam 3 are provided with comb tooth unit, and DEFT resonant beam 3 is provided with heat insulation layer, and the comb tooth unit includes oppositely arranged comb tooth moving tooth 4 and comb tooth fixed tooth, and the comb tooth fixed tooth includes first comb tooth fixed tooth 5 and second comb tooth fixed tooth 6, and the first comb tooth fixed tooth 5 is arranged on the side of comb tooth moving tooth 4 away from DEFT resonant beam 3, and the second comb tooth fixed tooth 6 is arranged on the side of comb tooth moving tooth 4 close to DEFT resonant beam 3.

[0056] Further, the second comb tooth fixed tooth 6 is sequentially provided with two in the axial direction.

[0057] Further, the second comb tooth fixed tooth 6 is sequentially provided with two in the axial direction.

[0058] Further, when being installed, the movable comb teeth 4, the first fixed comb teeth 5 and the second fixed comb teeth 6 are all nested with each other and have the same interval.

[0059] Further, the movable comb teeth 4, the first fixed comb teeth 5 and the second fixed comb teeth 6 are all bonded on the glass substrate 7.

[0060] Further, the utility model discloses an embodiment discloses that when working, the fundamental frequency of MEMS resonator is:

[0061]

[0062] In the formula, E is the Young's modulus of monocrystalline silicon, w is the width of resonator side beam, L is the length of resonator side beam, rho is the density of monocrystalline silicon, A1 is the surface area of MEMS resonator, A f In the specific embodiment, when the resonator side beam is subjected to tension or pressure, the resonant frequency changes, and the resonant frequency of a single side beam can be expressed as:

[0063]

[0064] In the formula, E is the Young's modulus of monocrystalline silicon, w is the width of resonator side beam, L is the length of resonator side beam, h is the thickness of resonator side beam, F is the magnitude of force that a single resonator side beam is subjected to, and f0 is the fundamental frequency of the resonator.

[0065] The utility model discloses an embodiment discloses a kind of sensors, including the resonator structure described in the utility model embodiment.

[0066] The above is only preferred embodiment of the utility model, and is not used to limit the utility model, for the person skilled in the art, the utility model can have various changes and changes. Any modification, equivalent replacement, improvement etc. that is made within the spirit and principles of the utility model should be included in the protection scope of the utility model.

Claims

1. A resonator structure, characterized by The DEFT resonator structure comprises a glass substrate (7), a DEFT resonator beam (3) is arranged on the upper end surface of the glass substrate (7), and the two ends of the DEFT resonator beam (3) are connected with the glass substrate (7) through a thermal insulation spring unit. A comb tooth unit is arranged on the two sides of the DEFT resonator beam (3). A thermal insulation layer is arranged on the DEFT resonator beam (3).

2. A resonator structure according to claim 1, characterised in that The thermal insulation spring unit comprises a thermal insulation spring (2) connected with the DEFT resonator beam (3), and the thermal insulation spring (2) is connected with the glass substrate (7) through an anchor point (1).

3. A resonator structure according to claim 2, characterised in that The side wall of the thermal insulation spring (2) is connected with the end of the DEFT resonator beam (3). The two ends of the thermal insulation spring (2) are connected with the anchor point (1).

4. A resonator structure according to claim 3, characterised in that The anchor point (1) is connected with the glass substrate (7) through a bonding connection of an insulating silicon oxide layer.

5. A resonator structure as claimed in claim 1, characterised in that The thermal insulation layer is an SIO2 layer.

6. A resonator structure as claimed in claim 1, characterised in that The comb tooth unit comprises oppositely arranged comb tooth moving teeth (4) and comb tooth fixed teeth.

7. A resonator structure according to claim 6, characterised in that The comb tooth fixed teeth comprise a first comb tooth fixed tooth (5) and a second comb tooth fixed tooth (6). The first comb tooth fixed tooth (5) is arranged on the side of the comb tooth moving tooth (4) away from the DEFT resonator beam (3), The second comb tooth fixed tooth (6) is arranged on the side of the comb tooth moving tooth (4) close to the DEFT resonator beam (3).

8. A resonator structure according to claim 7, characterised in that The second comb tooth fixed tooth (6) is axially sequentially provided with two.

9. A resonator structure as claimed in claim 8, characterised in that The number of teeth of the second comb tooth fixed tooth (6) is 11, and the number of teeth of the first comb tooth fixed tooth (5) is 22.

10. A sensor, characterized by The DEFT resonator structure comprises a glass substrate (7), a DEFT resonator beam (3) is arranged on the upper end surface of the glass substrate (7), and the two ends of the DEFT resonator beam (3) are connected with the glass substrate (7) through a thermal insulation spring unit. A comb tooth unit is arranged on the two sides of the DEFT resonator beam (3). A thermal insulation layer is arranged on the DEFT resonator beam (3). The thermal insulation spring unit comprises a thermal insulation spring (2) connected with the DEFT resonator beam (3), and the thermal insulation spring (2) is connected with the glass substrate (7) through an anchor point (1). The side wall of the thermal insulation spring (2) is connected with the end of the DEFT resonator beam (3). The two ends of the thermal insulation spring (2) are connected with the anchor point (1). The anchor point (1) is connected with the glass substrate (7) through a bonding connection of an insulating silicon oxide layer. The thermal insulation layer is an SIO2 layer. The comb tooth unit comprises oppositely arranged comb tooth moving teeth (4) and comb tooth fixed teeth. The comb tooth fixed teeth comprise a first comb tooth fixed tooth (5) and a second comb tooth fixed tooth (6). The first comb tooth fixed tooth (5) is arranged on the side of the comb tooth moving tooth (4) away from the DEFT resonator beam (3), The second comb tooth fixed tooth (6) is arranged on the side of the comb tooth moving tooth (4) close to the DEFT resonator beam (3). The second comb tooth fixed tooth (6) is axially sequentially provided with two. The number of teeth of the second comb tooth fixed tooth (6) is 11, and the number of teeth of the first comb tooth fixed tooth (5) is 22. The DEFT resonator structure comprises a glass substrate (7), a DEFT resonator beam (3) is arranged on the upper end surface of the glass substrate (7), and the two ends of the DEFT resonator beam (3) are connected with the glass substrate (7) through a thermal insulation spring unit.

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