WO2020080592A1 - Mems accelerometer and manufacturing method thereof - Google Patents

Abstract

In order to form a distance between MEMS electrodes to be d or lower, by using a process of manufacturing an MEMS structure, whose minimum line width is limited to d, at a silicon foundry, the present invention may provide an MEMS accelerometer comprising: a proof mass floating and moving in the horizontal direction, and including a plurality of first electrodes extending by a predetermined length in a direction perpendicular to the moving direction; a first elastic body for elastically supporting opposite ends of the proof mass; a fixed electrode including a plurality of second electrodes extending by a predetermined length toward the proof mass; and a movable electrode disposed between the proof mass and the fixed electrode and including third electrodes disposed to overlap the first electrodes and the second electrodes positioned in opposite sides thereof, respectively, wherein the movable electrode floats and moves in the horizontal direction such that the third electrodes are attached to the second electrodes to reduce a distance between the first electrodes and the third electrodes.

Description

MEMS accelerometer and manufacturing method thereof

The present invention relates to a MEMS (Microelectromechanical Syetem) accelerometer and a method for manufacturing the same. More specifically, in a MEMS structure manufacturing process in which the minimum line width is limited to d in mass production foundries, the gap between MEMS electrodes can be narrowed to d to be applied to a technical field that simultaneously satisfies high frequency response and sensor sensitivity.

In recent years, with the development of micro-machining technology using MEMS technology, it is possible to realize miniaturization, high performance and low cost.

In the development of ultra-compact accelerometer, the effect that can be obtained through MEMS technology can be selected first. In addition to miniaturization, the application fields of MEMS optical sensors aimed at lower cost are car navigation, vehicle airbag control, camera or video camera shake prevention, cell phone, robot posture control, game gesture input recognition, HDD rotation and shock detection. There is a lamp, and the displacement of the verification mass in the accelerometer is changed by the applied acceleration, and it is common to use a displacement accelerometer that measures the applied acceleration by changing it to a voltage.

1 is a view for explaining the basic operation principle of the MEMS accelerometer.

A schematic MEMS accelerometer is constructed with a proof-mase suspended in a reference frame. When external acceleration is applied through the micromechanical spring (K) and the damper (D), the reference frame moves toward a given direction (y), but the proof-mass is in its original position by inertia. (z). Due to this operation, a displacement difference (x) on the proof-mass and the reference frame occurs, which is equal to x = y-z.

The dynamic behavior of device motion can be expressed using Newton's second law of motion (Eq. (2-1)).

, 식 (2-1)

, Equation (2-1)

, 식 (2-2)

, Equation (2-2)

)을 가정하면, 변위는 식 (2-2)와 같이 인가된 가속도에 비례한다.Steady state conditions (

Assuming), the displacement is proportional to the applied acceleration as in equation (2-2).

)과 변위차(x) 사이의 전달 함수는 식 (2-3)과 같이 나타날 수 있다.Given external force (

) And the displacement difference (x) can be expressed as Equation (2-3).

, 식 (2-3)

, Equation (2-3)

에 의해 결정될 수 있다. 따라서, 넓은 주파수 범위에서 가속도 감지 기능을 얻으려면 높은 공진 주파수가 필요하다.The MEMS accelerometer is a secondary spring-mass-damper system, and the operating bandwidth is mostly resonant frequency.

It can be determined by. Therefore, a high resonance frequency is required to obtain an acceleration sensing function in a wide frequency range.

The piezoelectric accelerometer, the piezoresistive accelerometer, and the capacitive accelerometer may be classified according to a conversion mechanism for a method for converting proof-mass movement into an electrical signal.

However, the piezoresistive accelerometer is not commercially available because it is difficult to form a piezoelectric material in a thin film state having good characteristics without static characteristics.

In addition, since the piezo-resistive accelerometer has a large characteristic change due to temperature change, and its compensation is difficult, the recent technological trend of the accelerometer sensor is toward the capacitive type.

These capacitive accelerometers have excellent characteristics because they have a small change in characteristics with temperature, and the signal processing circuit can be configured as a field-effect transistor with excellent integration without a separate process. You can.

Capacitive accelerometers use a varying capacitance between the proof-mass and the sensing electrode to detect external acceleration. This type of sensing can achieve low power operation and reduce the silicon process. It has the advantage of being easy to implement.

2 is a conceptual diagram schematically illustrating a capacitive accelerometer.

결과를 얻을 수 있다. 여기서

는 유전율을, A는 전극 면적, d는 전기 용량 갭(gap)을 의미한다.In a static condition (Fig. 2 (a)), the distance between the proof-mass and the sensing electrode is d, and consequently, as shown in Equation (2-4).

You can get results. here

Is the dielectric constant, A is the electrode area, and d is the capacitive gap.

, 식 (2-4)

, Equation (2-4)

)은 식 (2-5)로 표현될 수 있다.The sensing electrode is configured such that changes in the gap size due to movement of the verification mass (Fig. 2 (b)) have opposite polarities, and the capacitance differential value (

) Can be expressed by equation (2-5).

, 식 (2-5)

, Equation (2-5)

, 식 (2-6)

, Equation (2-6)

)으로 표현되는 스케일 팩터(scale factor)는 식 (2-7)과 같이 표현될 수 있다.If the displacement difference (x) is much smaller than the gap size (d), Eq. (2-5) can be simplified to Eq. (2-6), and the capacitance differential value for acceleration (

The scale factor represented by) may be expressed as Equation (2-7).

, 식 (2-7)

, Equation (2-7)

)을 통해 가속도를 감지할 수 있다.That is, the capacitive accelerometer is a capacitance differential value (

) To detect the acceleration.

Sensitivity and frequency range will be the most important if you take an important priority in selecting an accelerometer sensor. The frequency response range uniquely refers to the frequency section of the area where the measurement is accurate. The frequency response range refers to a trusted area where the sensor can properly output a signal, and the trusted area can be expressed as a linear section.

)과 변위차(x)는 비선형 관계에 있기 때문에, 중파수 응답 범위와 센서 감도는 도 3과 같이 트레이드 오프(trade-off)되는 관계가 나타난다.However, as shown in equation (2-5), the differential value of capacitance (

) And the displacement difference (x) are in a non-linear relationship, so that the medium frequency response range and the sensor sensitivity are traded off as shown in FIG. 3.

That is, when the signal sensitivity of the sensor is increased, the width of the detectable frequency is narrowed, and when the frequency response range is increased, the signal sensitivity is reduced.

A method that can simultaneously satisfy high frequency response and sensor sensitivity in a limited chip size (c in FIG. 3) is to narrow the gap between MEMS electrodes.

As a related research, nanogap accelerometer of Ayazi Lab of Georig tech, USA, which discloses the process technique of FIG. 4, is representative.

Specifically, when looking at the process technique of FIG. 4, both planar and out-of-plane accelerometers use SOI (Silicon) using the high aspect-ratio combined poly- and single-crystal silicon micromachining technology (HARPSS). -on-insulartor) can be made on a wafer (Fig. 4 (a)).

A Deep Reactive-Ion Etching (DRIE) trench that forms the appearance of a mechanical structure on a silicon wafer is etched. And a side capacitive gap can be defined by thermally growing the sacrificial oxide layer (FIG. 4 (b)).

Subsequently, a poly-silicon may be filled into the trench using a low pressure chemical vapor deposition (LPCVD) method (FIG. 4 (c)).

Thereafter, it is further patterned to define the top and bridging electrodes, and a sacrificial oxide layer for positioning the gap between the planes can be further grown (FIG. 4 (d)).

Thereafter, a polysilicon layer is deposited and can be patterned to define the top electrode for out-of-plane orientation (FIG. 4 (e)).

Thereafter, the sacrificial oxide layer may be removed from hydrofluoric acid (HF) to form a MEMS accelerator structure.

Thereafter, the MEMS accelerometer is bonded to the capping wafer to perform sealed wafer level vacuum packaging (1-10 Torr). At this time, the capping wafer may be separately processed by filling with an insulator to define a groove and to implement a through-silicon-via (TSV). Because the waver has a low resistance, the silicon through electrode (TSV) provides a low resistance path between the envelope pad and the internal MEMS device. The depression is etched prior to the capping process, and the gold pattern is defined to eutecticly bond with the MEMS wafer. After sealing, a gold metal trace and pad can be deposited on top of the capping wafer. (Fig. 4 (g), Fig. 4 (h))

However, the process method of Ayazi Lab's nanogap acceleration sensor requires complex process such as deposition of oxide film and polysilicon, selective removal of oxide film, and currently, the manufacturing process of MEMS structures in mass production foundries is limited to a minimum line width of about 2um.

Therefore, in order to reduce the minimum line width to 2 µm or less in the manufacturing process of MEMS structures, a lot of effort and resources are required to improve process equipment and process techniques.

The present invention aims to solve the above-mentioned problems and other problems through the specification of the present invention.

It is an object of the present invention to provide a MEMS accelerometer with an inter-electrode spacing less than the minimum processable line width in silicon foundries.

An object of the present invention is to realize the performance of high sensitivity and high frequency response through a MEMS accelerometer by reducing the gap between electrodes.

SUMMARY OF THE INVENTION The present invention aims to reduce the spacing between electrodes of a MEMS accelerometer with a minimum of a processable line width in a MEMS accelerometer structure processing method in which the minimum processable line width is limited in silicon foundries, without design process improvement.

In order to achieve the above object, according to one embodiment of the present invention, the verification mass including a plurality of first electrodes floating and moving in the horizontal direction and extending a predetermined length in the vertical direction to the movement direction, both ends of the verification mass A first elastic body elastically supported, a fixed electrode including a plurality of second electrodes extending a predetermined length toward the verification mass, and the first electrode provided between the verification mass and the fixed electrode and located on both sides And a third electrode, each of which is disposed overlapping the second electrode, wherein the third electrode is attached to the second electrode to reduce a gap between the first electrode and the third electrode. It provides a MEMS accelerometer characterized in that it floats and moves in a horizontal direction.

In addition, according to an embodiment of the present invention to achieve the above object, the mobile electrode is moved by a constant power between the third electrode and the second electrode MEMS accelerometer, characterized in that fixed to the fixed electrode to provide.

In addition, according to an embodiment of the present invention to achieve the above object, the first electrode and the third electrode in one direction and the second electrode and the third electrode in the other direction are respectively disposed overlap, the first MEMS accelerometer, characterized in that the line width direction between the electrode and the one-way third electrode is parallel to the line width direction between the third electrode and the second electrode in the other direction.

In addition, according to an embodiment of the present invention to achieve the above object, the gap between the third electrode and the second electrode provides a MEMS accelerometer, characterized in that less than the gap between the third electrode and the first electrode do.

In addition, according to an embodiment of the present invention to achieve the above object, the MEMS accelerometer provides a MEMS accelerometer further comprising a second elastic body elastically supporting both ends of the mobile electrode.

In addition, according to an embodiment of the present invention to achieve the above object, the second elastic body provides a MEMS accelerometer characterized in that the third electrode provides an asymmetrical external force to maintain the attachment state to the second electrode. to provide.

In addition, according to an embodiment of the present invention to achieve the above object, the verification mass forms one body, and is provided to surround each of the fixed electrodes provided symmetrically on one plane, and the movement MEMS accelerometer, characterized in that two electrodes are provided symmetrically between the two fixed electrodes and the verification mass.

In addition, according to another embodiment of the present invention to achieve the above object, in a method of manufacturing a MEMS accelerometer with a minimum line width processable in silicon foundries limited to d, a plurality of verification masses floating and moving horizontally in the process. The line width between the first electrode and the third electrode in one direction of the movable electrode floating and moving horizontally is formed by d + a (a <d), the second electrode of the fixed fixed electrode and the third of the other electrode of the mobile electrode Forming a line width between electrodes to a minimum d, moving the moving electrode during the design process to attach the second electrode and the third electrode in the other direction, and a minimum line width between the first electrode and the one-way third electrode a It provides a method of manufacturing a MEMS accelerometer comprising the step of forming.

In addition, according to another embodiment of the present invention to achieve the above object, the design process comprises moving the moving electrode by a constant power between the third electrode and the second electrode in the other direction. Provided is a method of manufacturing a MEMS accelerometer.

In addition, according to another embodiment of the present invention to achieve the above object, the process step of the first electrode and the one-way third electrode and the second electrode and the other electrode in the third direction are overlapped, respectively Provided is a method of manufacturing a MEMS accelerometer, wherein the line width direction between the second electrode and the third electrode in the other direction is parallel to the line width direction between the third electrode and the second electrode in the other direction.

Further, according to another embodiment of the present invention to achieve the above object, the design process elastically supports both ends of the verification mass by a first elastic body, and both ends of the movable electrode are burnt by a second elastic body. It provides a method of manufacturing a MEMS accelerometer characterized in that it is designed to be sexually supported.

In addition, according to another embodiment of the present invention to achieve the above object, the design process provides an asymmetrical external force such that the second elastic body maintains an attachment state between the third electrode and the second electrode in the other direction. It provides a method of manufacturing a MEMS accelerometer, characterized in that.

In addition, according to another embodiment of the present invention to achieve the above object, the process process is such that the verification mass forms one body, and is formed to surround each of the fixed electrodes symmetrically provided on one plane. And, it provides a method of manufacturing a MEMS accelerometer, characterized in that the moving electrode is formed to be provided symmetrically between the two fixed electrodes and the verification mass.

When explaining the effect of the MEMS accelerometer and the manufacturing method according to the present invention are as follows.

The present invention can fabricate MEMS accelerometers with inter-electrode spacing smaller than the minimum line width processable in silicon foundries.

The present invention can realize high-sensitivity and high-frequency response performance through a MEMS accelerometer by reducing the gap between electrodes.

The present invention can reduce the gap between the electrodes of the MEMS accelerometer using only the design technology through the existing process technology, without the effort and resources required to reduce the minimum processable line width in the silicon foundry process.

Further scope of applicability of the present invention will become apparent from the following detailed description. However, various changes and modifications within the spirit and scope of the present invention can be clearly understood by those skilled in the art, and thus, specific embodiments such as detailed description and preferred embodiments of the present invention are to be understood as examples only. Should be.

1 is a view for explaining the basic operation principle of the MEMS accelerometer.

2 is a conceptual diagram schematically illustrating a capacitive accelerometer.

3 is a diagram for explaining a correlation between a signal sensitivity and a frequency response range in a capacitive accelerometer.

4 is a view showing an embodiment of a MEMS accelerometer process method.

5 is a view for explaining a conventional capacitive accelerometer.

6 is a view for explaining a capacitive accelerometer according to the present invention.

FIG. 7 is an enlarged view of FIG. 6B, and is a view for explaining a method of reducing the inter-electrode spacing in the capacitive accelerometer according to the present invention.

8 is a view for explaining an embodiment of the capacitive accelerometer according to the present invention.

Hereinafter, exemplary embodiments disclosed herein will be described in detail with reference to the accompanying drawings, but the same or similar elements are assigned the same reference numbers regardless of the reference numerals, and overlapping descriptions thereof will be omitted. The suffixes "modules" and "parts" for the components used in the following description are given or mixed only considering the ease of writing the specification, and do not have meanings or roles distinguished from each other in themselves. In addition, in describing the embodiments disclosed in the present specification, when it is determined that detailed descriptions of related known technologies may obscure the gist of the embodiments disclosed herein, detailed descriptions thereof will be omitted. In addition, the accompanying drawings are only for easy understanding of the embodiments disclosed in the present specification, and the technical spirit disclosed in the specification is not limited by the accompanying drawings, and all modifications included in the spirit and technical scope of the present invention , It should be understood to include equivalents or substitutes.

Terms including ordinal numbers such as first and second may be used to describe various components, but the components are not limited by the terms. The terms are used only for the purpose of distinguishing one component from other components.

When an element is said to be "connected" or "connected" to another component, it is understood that other components may be directly connected to or connected to the other component, but other components may exist in the middle. It should be. On the other hand, when a component is said to be "directly connected" or "directly connected" to another component, it should be understood that no other component exists in the middle.

Singular expressions include plural expressions unless the context clearly indicates otherwise.

In this application, the terms "comprises" or "have" are intended to indicate the presence of features, numbers, steps, actions, components, parts or combinations thereof described herein, one or more other features. It should be understood that the existence or addition possibilities of fields or numbers, steps, operations, components, parts or combinations thereof are not excluded in advance.

5 is a view for explaining a conventional capacitive accelerometer.

Before looking at the features of the present invention, the basic structure of the existing capacitive MEMS accelerometer is outlined as follows.

Existing capacitive MEMS accelerometers are supported by the first elastic body 514 and the first elastic body elastically supporting both ends of the verification mass 511, which is a movable structure that can be floated and moved. The first anchor 513, a plurality of first electrodes 512, fixed fixed electrodes 521, which are warranted to the outer surface of the verification mass 511 in a direction perpendicular to the direction of movement of the verification mass 511, and The fixed electrode 521 may include a second electrode 522 extending in the direction of the verification mass 511 and overlapping the first electrode.

In the conventional MEMS accelerometer having the above configuration, when an inertial force is applied from the outside, the verification mass 511 moves in a direction in which the inertial force acts, and the first electrode 512 connected to the verification mass moves in the same direction. , Accordingly, the distance from the second electrode 522 of the fixed electrode 521 is reduced. (Part A of FIG. 5)

Accordingly, the capacitance between the first electrode 512 and the second electrode 522 changes, and the change in the capacitance induces a change in the sense voltage applied to the classic electrode 521, It is amplified and measured through an amplifier (not shown) connected to the first electrode 512 to measure the applied acceleration.

The MEMS accelerometer may be provided by intersecting the first electrode 512 and the second electrode 522 in a comb type in order to further enlarge the amount of change in the capacitance output with respect to acceleration.

The signal sensitivity and frequency response range of the MEMS accelerometer may be determined at intervals of the portion A in FIG. 5.

As described in FIG. 3, in order to simultaneously satisfy the signal sensitivity and frequency response range having a trade-off relationship, it is necessary to reduce the interval of part A of FIG. 5, considering the conventional MEMS accelerometer process technique as described in FIG. In the process of reducing the spacing of part A of FIG. 5 in the process of lower surface, a lot of effort and resources are required.

Therefore, using the existing process technique, the features of the present invention to reduce the spacing of part A of FIG. 5 in the design process will be described below.

6 is a view for explaining a capacitive accelerometer according to the present invention.

The MEMS accelerometer according to the present invention is suspended, moves in a horizontal direction, and includes a verification mass 511 including a plurality of first electrodes 612 extending in a vertical direction in the movement direction, and both ends of the verification mass 611. The first elastic body 614 to elastically support, the fixed electrode 621 including a plurality of second electrodes 622 extending a predetermined length toward the verification mass 611, and the verification mass 611 The movable electrode 631 is provided between the fixed electrodes 621 and includes a third electrode 632 overlapping the first electrode 612 and the second electrode 622 positioned on both sides. Including, the mobile electrode 631 is suspended so that the third electrode 632 is attached to the second electrode 622 to reduce the gap between the first electrode 611 and the third electrode 632. It can move in the horizontal direction.

The moving electrode 621 may be suspended in a direction parallel to the direction in which the verification mass 611 moves, and may be elastically supported at both ends through the second elastic body 631. Specifically, the verification mass 611 and the moving electrode 621 may be elastically supported by the first elastic body 614 and the second elastic body connected to the first anchor 613 and the second anchor 633, respectively. .

In addition, the moving electrode 621 may include a third electrode 632a in one direction and a third electrode 632b in the other direction extending in a predetermined length in both directions vertically in the moving direction, and the third electrode ( 632a) may be overlapped with the first electrode 612, and the third electrode 632a in the other direction may be overlapped with the second electrode 612.

Specifically, the first electrode 612 and the third electrode 632a in one direction, and the second electrode 621 and the third electrode 632b in the other direction are overlapped, respectively, and the first electrode 612 and the The line width direction between the third electrode 632a in one direction may be parallel to the line width direction between the third electrode 632b and the second electrode 622 in the other direction.

In this case, an interval between the third electrode 632b in the other direction and the second electrode 622 may be smaller than an interval between the third electrode 632a and the first electrode 612 in one direction. This is characterized in that the feature of the present invention is to reduce the gap between the first electrode 612 and the third electrode 632a in one direction. In this regard, it will be described in detail in FIG. 7.

FIG. 7 is an enlarged view of FIG. 6B, and is a view for explaining a method of reducing the inter-electrode spacing in the capacitive accelerometer according to the present invention.

7 (a) is a method of manufacturing a MEMS accelerometer in which the minimum line width processable in silicon foundries is limited to d, a plurality of first electrodes 612 and suspensions of the verification mass 611 suspended and horizontally moved in the process. The line width between the one-way third electrode 632a of the movable electrode 631 moving horizontally is formed as d + a, and the second electrode 622 of the fixed fixed electrode 621 and the other of the movable electrode 631 An embodiment in which the line width between the third electrodes 632b in the direction is minimum d (d ′> = d in FIG. 7 (a)) is illustrated.

Subsequently, in the design process as shown in FIG. 7 (b), the moving electrode 631 is moved in the C direction to attach the second electrode 622 and the third electrode 632b in the other direction, and the first electrode The line width between 612 and the third electrode 632a in one direction may be formed to a minimum of a (d + a-d 'in FIG. 7 (b)).

That is, the present invention uses a conventional process method in which the minimum line width that can be processed in silicon foundries is limited to d, and the distance between the first electrode 612 and the third electrode 632a in one direction, which is caused by a change in capacitance, is greater than d It can be implemented with a small a.

At this time, the third electrode 632b and the second electrode 622 in the other direction are attached by a constant power, and the movable electrode 631 may be fixed to the fixed electrode 621.

When the verification mass 611 moves due to inertia and the capacitance between the first electrode 612 and the third electrode 632a in one direction changes, the change in the capacitance is the first direction connected to the conductor. An amplifier (not shown) connected to the first electrode 512 is induced by inducing a change in the sensing voltage applied to the fixed electrode 521 through the third electrode 632a and the third electrode 632b in the other direction. It can be amplified and measured.

The third electrode 632b and the second electrode 622 in the other direction may be attached by using pull-in, adhesion, and stiction phenomena in addition to constant power, and in some cases, a second elastic body that provides an asymmetrical external force ( 634).

Through the above design fixation, the present invention can form the gap between the electrodes of the MEMS accelerometer to less than 0.5 nm less than 2 μm using the process method of the nanogap acceleration sensor of Ayazi Lab illustrated in FIG. 4.

8 is a view for explaining an embodiment of the capacitive accelerometer according to the present invention.

In the present invention, as described in FIG. 8, the fixed electrode 621 and the movable electrode 631 may be symmetrically provided on a plane.

Specifically, the verification mass 611 forms one body, and is provided to surround each of the fixed electrodes 621 provided symmetrically on one plane, and the movable electrode 631 is fixed to the two Two electrodes may be symmetrically provided between the electrode 621 and the verification mass 611.

The verification mass 611 is connected to the first anchor 613 through the first elastic body 614 and is movable in one direction by inertia, and the moving electrode 611 is the second elastic body to the second anchor 633 It is fixed to (614), it is possible to support the third electrode (632b) in the other direction to move to be attached to the second electrode (622).

The above detailed description should not be construed as limiting in all respects, but should be considered illustrative. The scope of the present invention should be determined by rational interpretation of the appended claims, and all changes within the equivalent scope of the present invention are included in the scope of the present invention.

Claims (13)

A verification mass including a plurality of first electrodes floating and moving in a horizontal direction and extending a predetermined length in a vertical direction to the moving direction; A first elastic body elastically supporting both ends of the verification mass; A fixed electrode including a plurality of second electrodes extending a predetermined length toward the verification mass; And, Includes; between the verification mass and the fixed electrode, the movable electrode including a third electrode disposed on each side of the first electrode and the second electrode disposed on both sides; The moving electrode MEMS accelerometer, characterized in that the third electrode is attached to the second electrode and suspended to move in a horizontal direction so as to reduce the gap between the first electrode and the third electrode. According to claim 1, The moving electrode MEMS accelerometer, characterized in that the third electrode and the second electrode is moved by a constant power and fixed to the fixed electrode. According to claim 1, The first electrode and the third electrode in one direction and the second electrode and the third electrode in the other direction are overlapped, and a line width direction between the first electrode and the third electrode in one direction is the third in the other direction. MEMS accelerometer, characterized in that parallel to the line width direction between the electrode and the second electrode. According to claim 1, MEMS accelerometer, characterized in that the gap between the third electrode and the second electrode is smaller than the gap between the third electrode and the first electrode. According to claim 1, The MEMS accelerometer MEMS accelerometer, characterized in that it further comprises a second elastic body elastically supporting both ends of the mobile electrode. The method of claim 5, The second elastic body MEMS accelerometer, characterized in that to provide an asymmetrical external force so that the third electrode remains attached to the second electrode. According to claim 1, The verification mass is It forms one body, and is provided to surround each of the fixed electrodes symmetrically provided on one plane. The moving electrode MEMS accelerometer, characterized in that two symmetrically provided between the two fixed electrodes and the verification mass. A method of manufacturing a MEMS accelerometer with a minimum line width processable in silicon foundries limited to d, In the process, the line width between the plurality of first electrodes of the verifying mass suspended and moving horizontally and the third electrode in one direction of the moving electrodes floating and moving horizontally is formed as d + a (a <d), and the fixed fixed electrode Forming a line width between the second electrode and the third electrode in the other direction of the mobile electrode to a minimum d; In the design process, moving the moving electrode to attach the second electrode and the third electrode in the other direction, and forming a line width between the first electrode and the one-way third electrode to a minimum a MEMS accelerometer comprising a Method of manufacturing. The method of claim 8, The design process is MEMS is a method of manufacturing an accelerometer comprising moving the mobile electrode by a constant power between the third electrode and the second electrode in the other direction. The method of claim 8, The process is The first electrode, the one-way third electrode, the second electrode, and the third electrode in the other direction are overlapped, and the line width direction between the second electrode and the third electrode in the other direction is the third electrode in the other direction. MEMS accelerometer manufacturing method, characterized in that parallel to the line width direction between the second electrode. The method of claim 8, The design process is A method of manufacturing a MEMS accelerometer, characterized in that both ends of the verification mass are designed to be elastically supported by a first elastic body, and both ends of the movable electrode are elastically supported by a second elastic body. The method of claim 11, The design process is A method of manufacturing a MEMS accelerometer, wherein the second elastic body provides an asymmetrical external force so that the third electrode in the other direction remains attached to the second electrode. The method of claim 8, The revolution process The verification mass forms one body, and is formed to surround each of the fixed electrodes symmetrically provided on one plane, and the movable electrode is symmetrically placed between the two fixed electrodes and the verification mass. Method of manufacturing a MEMS accelerometer, characterized in that formed to be provided.

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