MEMS anchor point structure for isolating stress and inhibiting anchor point loss and carrier thereof

Abstract

The utility model relates to an MEMS anchor point structure for isolating stress and inhibiting anchor point loss and a carrier thereof, the MEMS anchor point structure for isolating stress and inhibiting anchor point loss comprises a central support block and an outer frame, and a plurality of stress isolation beam assemblies and a plurality of stress wave reflection rings are arranged between the central support block and the outer frame. A plurality of stress isolation supporting columns are arranged at the bottom of the center supporting block. According to the MEMS anchor point structure, the influence of stress generated by packaging and temperature change on the performance of a device is effectively reduced, meanwhile, the anchor point loss is reduced, and the quality factor is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of MEMS, in particular to a MEMS anchor point structure and a carrier thereof capable of isolating stress and suppressing anchor point loss. Background Art

[0002] Anchor loss, also known as support loss, is one of the primary energy dissipation mechanisms in micro-electro-mechanical systems (MEMS). It occurs when a resonant body periodically deforms at its anchor point during vibration, generating cyclic forces and torques. These forces then serve as excitation sources for acoustic and elastic waves. The energy of these stress waves is not fully reflected at the boundary, but instead propagates through the anchor point toward the substrate and beyond, causing energy dissipation.

[0003] Devices such as gyroscopes, resonators, and accelerometers based on MEMS technology can be viewed as an oscillating system consisting of an anchor point, an elastic beam, and a mass block. There are usually many anchor points connecting the elastic beams in the structure. Using conventional anchor point structures often results in high anchor point damping, affecting the quality factor of the device.

[0004] During the packaging process, due to the mismatch of thermal expansion coefficients between the chip, substrate, and epoxy adhesive (or the difference in thermal expansion coefficients between the chip substrate, insulation layer, structural layer, and cover), temperature changes will generate stress. This stress can be transmitted to the elastic beam through the anchor point, affecting the stiffness of the beam and causing sensitivity errors.

[0005] In order to reduce anchor point damping and mitigate the impact of stress caused by packaging and temperature changes on device performance, it is necessary to provide a MEMS anchor point structure that isolates stress and suppresses anchor point loss. Utility Model Content

[0006] The technical problem to be solved by the present invention is to provide a MEMS anchor structure that isolates stress and suppresses anchor loss. The MEMS anchor structure not only effectively reduces the impact of stress caused by packaging and temperature change on device performance, but also reduces anchor loss and improves the quality factor.

[0007] The technical solution adopted by the utility model to solve its technical problems is: a MEMS anchor structure that isolates stress and suppresses anchor loss, including a central support block and an outer frame, a plurality of stress isolation beam assemblies and a plurality of stress wave reflection rings are arranged between the central support block and the outer frame, and a plurality of stress isolation support columns are arranged at the bottom of the central support block.

[0008] In one embodiment, the stress isolation beam assembly of the MEMS anchor structure that isolates stress and suppresses anchor loss includes a first stress isolation beam and a second stress isolation beam, one end of the first stress isolation beam is vertically connected to the outer frame, the other end of the first stress isolation beam is vertically connected to the side end of the central support block, one end of the second stress isolation beam is connected to the end corner of the central support block, and the other end of the second stress isolation beam is connected to the end corner of the outer frame.

[0009] In one embodiment, the stress isolation beam assembly of the MEMS anchor structure for isolating stress and suppressing anchor loss further includes a reinforcement beam, which is coupled to the middle portion of the first stress isolation beam and the second stress isolation beam respectively.

[0010] In one embodiment, the stress wave reflection ring of the MEMS anchor structure for isolating stress and suppressing anchor loss is an arc-shaped structure.

[0011] A MEMS anchor structure carrier includes several MEMS anchor structures that isolate stress and suppress anchor loss, and also includes a substrate, several elastic beams and a mass block. The mass block is provided with a groove to accommodate the elastic beams and the MEMS anchor structure. One end of the elastic beam is connected to one end of the MEMS anchor structure outer frame provided with a stress wave reflection ring, and the other end of the elastic beam is connected to the bottom of the groove of the mass block. One end of the stress isolation support column is connected to the bottom of the central support block, and the other end of the stress isolation support column is connected to the substrate.

[0012] The beneficial effects of this application are:

[0013] The present application provides a MEMS anchor structure that isolates stress and suppresses anchor loss. The MEMS anchor structure adopts a design method of stress isolation beam assembly plus stress isolation support column to form double stress isolation, which can effectively reduce the impact of stress caused by packaging and temperature change on device performance.

[0014] The MEMS anchor structure also uses a stress wave reflection ring to reflect most of the acoustic and elastic wave energy propagating toward the anchor during device operation back to the resonator, reducing anchor loss and improving the quality factor.

[0015] The MEMS anchor structure can be realized synchronously with the main structure of MEMS chips such as gyroscopes, resonators, and accelerometers using etching technology without adding additional process steps. It also has the advantages of easy processing technology, suitability for mass manufacturing, and low cost.

[0016] The present application also provides a MEMS anchor structure carrier, which can maximize the beneficial effects of the MEMS anchor structure of the present application on the device by using the MEMS anchor structure in combination with an elastic beam, a mass block, and a substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A front view schematic diagram of a MEMS anchor structure for isolating stress and suppressing anchor loss according to an embodiment of the present application;

[0018] Figure 2 A schematic back view of a MEMS anchor structure for isolating stress and suppressing anchor loss according to an embodiment of the present application;

[0019] Figure 3 A schematic diagram of a MEMS anchor structure and its carrier for isolating stress and suppressing anchor loss according to an embodiment of the present application;

[0020] Figure 4 This is a left view of a MEMS anchor structure and its carrier for isolating stress and suppressing anchor loss according to an embodiment of the present application;

[0021] in:

[0022] 1. Central support block; 2. Stress isolation beam assembly; 201. First stress isolation beam; 202. Second stress isolation beam; 3. Stress isolation support column; 4. Stress wave reflection ring; 5. Reinforcement beam; 6. Outer frame; 7. Substrate; 8. Elastic beam; 9. Mass block. DETAILED DESCRIPTION

[0023] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0024] like Figure 1 and Figure 2 As shown, an embodiment of the present application provides a MEMS anchor structure that isolates stress and suppresses anchor loss, including a central support block 1 and an outer frame 6, a plurality of stress isolation beam assemblies 2 and a plurality of stress wave reflection rings 4 are arranged between the central support block 1 and the outer frame 6, and a plurality of stress isolation support columns 3 are arranged at the bottom of the central support block 1.

[0025] Specifically, the central support block 1 and the outer frame 6 are each a square structure. The outer frame 6 is located outside the central support block 1. Three stress isolation beam assemblies 2 are provided between the outer frame 6 and the three corresponding end faces of the central support block 1. The first stress isolation beam 201 of the stress isolation beam assembly 2 is respectively connected perpendicularly to the outer frame 6 and the central support block 1, and the second stress isolation beam 202 of the stress isolation beam assembly 2 is respectively connected to the outer frame 6 and the end corners of the central support block 1. A stress wave reflection ring 4 is provided between the outer frame 6 and the fourth corresponding end face of the central support block 1. Five stress isolation support columns 3 are provided in an array at the bottom of the central support block 1, and the other ends of the five stress isolation support columns 3 are connected to the substrate 7.

[0026] In the above structure, a stress isolation beam assembly 2 plus a stress isolation support column 3 are used to create dual stress isolation, effectively reducing the impact of stress caused by packaging and temperature changes on device performance. A stress wave reflection ring 4 is also used to reflect most of the acoustic and elastic wave energy propagating toward the anchor point during device operation back to the resonator, reducing anchor point losses and improving the quality factor. This MEMS anchor point structure can also be implemented using etching technology simultaneously with the main structure of MEMS chips such as gyroscopes, resonators, and accelerometers, without adding additional process steps. It also has the advantages of easy processing, suitability for mass production, and low cost.

[0027] like Figure 1 and Figure 2 As shown, in one embodiment, the stress isolation beam assembly 2 of the MEMS anchor structure for isolating stress and suppressing anchor loss includes a first stress isolation beam 201 and a second stress isolation beam 202, one end of the first stress isolation beam 201 is vertically connected to the outer frame 6, the other end of the first stress isolation beam 201 is vertically connected to the side end of the central support block 1, one end of the second stress isolation beam 202 is connected to the end corner of the central support block 1, and the other end of the second stress isolation beam 202 is connected to the end corner of the outer frame 6.

[0028] Specifically, three first stress-isolating beams 201 and two second stress-isolating beams 202 are provided between the outer frame 6 and the central support block 1. The first stress-isolating beams 201 are perpendicularly connected to the middle portions of the outer frame 6 and the central support block 1, respectively. The second stress-isolating beams 202 are connected to the corners of the outer frame 6 and the central support block 1, respectively. This arrangement facilitates stress isolation and effectively reduces the impact of stress caused by packaging and temperature fluctuations on device performance.

[0029] like Figure 1 and Figure 2 As shown, in one embodiment, the stress isolation beam assembly 2 of the MEMS anchor structure for isolating stress and suppressing anchor loss also includes a reinforcement beam 5, which is coupled to the middle parts of the first stress isolation beam 201 and the second stress isolation beam 202 respectively.

[0030] Specifically, three reinforcement beams 5 are provided between the outer frame 6 and the central support block 1, and the reinforcement beams 5 are respectively coupled to the middle portions of the first stress isolation beam 201 and the second stress isolation beam 202. This arrangement strengthens the anchor structure and improves stability during use.

[0031] like Figure 1 and Figure 2As shown, in one embodiment, the stress wave reflection ring 4 of the MEMS anchor structure, which isolates stress and suppresses anchor loss, is an arc-shaped structure. This stress wave reflection ring 4 is composed of multiple arc-shaped reflection rings of different diameters. The reflection rings near the central support block 1 are connected to two reinforcement beams 5. This arrangement can reflect most of the acoustic and elastic wave energy propagating toward the anchor point during device operation back to the resonator, reducing anchor point damping and improving the quality factor.

[0032] like Figure 3 and Figure 4 As shown, an embodiment of the present application also provides a MEMS anchor structure carrier, including several MEMS anchor structures that isolate stress and suppress anchor loss, and also includes a substrate 7, several elastic beams 8 and a mass block 9. The mass block 9 is provided with a groove to accommodate the elastic beam 8 and the MEMS anchor structure. One end of the elastic beam 8 is connected to one end of the MEMS anchor structure outer frame 6 provided with a stress wave reflection ring 4, and the other end of the elastic beam 8 is connected to the bottom of the groove of the mass block 9. One end of the stress isolation support column 3 is connected to the bottom of the central support block 1, and the other end of the stress isolation support column 3 is connected to the substrate 7.

[0033] Specifically, two MEMS anchor structures and two elastic beams 8 can be provided, with a mass block 9 positioned above a substrate 7. The two MEMS anchor structures are respectively connected to the grooves of the mass block 9 via two elastic beams 8, and the stress isolation support columns 3 of the two anchor structures are respectively connected to the substrate 7. This arrangement can maximize the beneficial effects of the MEMS anchor structures on the device.

[0034] The above-described embodiments merely represent several implementations of the present invention. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that a person skilled in the art would be able to make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements fall within the scope of protection of the present invention. Therefore, the scope of protection of the present utility model patent shall be determined by the appended claims.

Claims

1. A MEMS anchor structure that isolates stress and suppresses anchor loss, characterized in that: It comprises a central support block (1) and an outer frame (6), a plurality of stress isolation beam assemblies (2) and a plurality of stress wave reflection rings (4) are arranged between the central support block (1) and the outer frame (6), and a plurality of stress isolation support columns (3) are arranged at the bottom of the central support block (1); The stress isolation beam assembly (2) comprises a first stress isolation beam (201) and a second stress isolation beam (202); one end of the first stress isolation beam (201) is vertically connected to the outer frame (6); the other end of the first stress isolation beam (201) is vertically connected to the side end of the central support block (1); one end of the second stress isolation beam (202) is connected to the end corner of the central support block (1); and the other end of the second stress isolation beam (202) is connected to the end corner of the outer frame (6).

2. The MEMS anchor structure for isolating stress and suppressing anchor loss according to claim 1, characterized in that: The stress isolation beam assembly (2) further comprises a reinforcement beam (5), wherein the reinforcement beam (5) is coupled to the middle portions of the first stress isolation beam (201) and the second stress isolation beam (202), respectively.

3. The MEMS anchor structure for isolating stress and suppressing anchor loss according to claim 1, characterized in that: The stress wave reflection ring (4) is an arc-shaped structure.

4. A MEMS anchor structure carrier, comprising a plurality of MEMS anchor structures for isolating stress and suppressing anchor loss according to any one of claims 1 to 3, characterized in that: The invention also includes a substrate (7), a plurality of elastic beams (8) and a mass block (9); a groove for accommodating the elastic beam (8) and the MEMS anchor structure is provided on the mass block (9); one end of the elastic beam (8) is connected to one end of the MEMS anchor structure outer frame (6) provided with a stress wave reflection ring (4); the other end of the elastic beam (8) is connected to the bottom of the groove of the mass block (9); one end of the stress isolation support column (3) is connected to the bottom of the central support block (1); and the other end of the stress isolation support column (3) is connected to the substrate (7).

Images