CN110095632B - MEMS accelerometer based on zero correction - Google Patents
MEMS accelerometer based on zero correction Download PDFInfo
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- CN110095632B CN110095632B CN201910458116.2A CN201910458116A CN110095632B CN 110095632 B CN110095632 B CN 110095632B CN 201910458116 A CN201910458116 A CN 201910458116A CN 110095632 B CN110095632 B CN 110095632B
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Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
- G01P15/00—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
- G01P15/02—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses
- G01P15/08—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
- G01P15/00—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
- G01P15/02—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses
- G01P15/08—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values
- G01P15/125—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values by capacitive pick-up
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
- G01P15/00—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
- G01P15/02—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses
- G01P15/08—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values
- G01P15/13—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values by measuring the force required to restore a proofmass subjected to inertial forces to a null position
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
- G01P15/00—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
- G01P15/02—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses
- G01P15/08—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values
- G01P2015/0862—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values being provided with particular means being integrated into a MEMS accelerometer structure for providing particular additional functionalities to those of a spring mass system
- G01P2015/0868—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values being provided with particular means being integrated into a MEMS accelerometer structure for providing particular additional functionalities to those of a spring mass system using self-test structures integrated into the microstructure
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Abstract
The invention discloses a MEMS accelerometer based on zero correction, comprising: the substrate is equipped with the oxide layer on the substrate, and a plurality of anchor points are fixed on the substrate through the oxide layer, are equipped with sensitive device layer on the oxide layer, and sensitive device layer includes: the accelerometer comprises a differential capacitance detection structure, an accelerometer closed-loop feedback electrode structure, a plurality of cantilever beams, a zero correction structure, a sensitive mass block, 2 stop structures and 2 fixed structures; the accelerometer structure is designed to correct the problem of different zero output changes of the structure caused by changes of machining errors, installation errors, ambient temperature and the like, and eliminate the influence of the zero output changes on the stability, temperature characteristics and other performances of the device.
Description
Technical Field
The invention relates to the field of micro-mechanical MEMS accelerometers, in particular to a zero correction-based MEMS accelerometer.
Background
The micro-mechanical MEMS accelerometer is a device or apparatus for measuring the acceleration, and has wide application requirements in high-precision fields such as industrial control, aviation, aerospace, military and the like. However, because the MEMS accelerometer has structural processing errors in the production process, and has installation errors and changes of ambient temperature and the like in the use process, the zero output of the device will change differently, which not only affects the mass production of the MEMS accelerometer, but also greatly affects the stability, temperature characteristics and other performances of the device, and the comprehensive precision is not high, which seriously hinders the application of the MEMS accelerometer in the high-precision field. Accordingly, there is a need for improved strategies to correct for MEMS accelerometer null output.
Disclosure of Invention
The invention provides a zero correction-based MEMS accelerometer, which can correct the problem of different zero output changes of the structure caused by changes of processing errors, installation errors, environmental temperature and the like through designing the accelerometer structure, and eliminate the influence of the zero changes on the stability, temperature characteristics and the like of the device.
To achieve the above object, the present application provides a MEMS accelerometer based on null correction, the accelerometer comprising:
the substrate is equipped with the oxide layer on the substrate, and a plurality of anchor points are fixed on the substrate through the oxide layer, are equipped with sensitive device layer on the oxide layer, and sensitive device layer includes: the accelerometer comprises a differential capacitance detection structure, an accelerometer closed-loop feedback electrode structure, a plurality of cantilever beams, a zero correction structure, a sensitive mass block, 2 stop structures and 2 concave fixing structures;
the differential capacitance detection structure is connected with the anchor point and the sensitive mass block and is used for detecting capacitance change caused by an acceleration signal; the accelerometer closed loop feedback electrode structure is connected with the anchor point and the sensitive mass block and is used for balancing displacement caused by an acceleration signal so as to keep the sensitive mass block at a mechanical zero position;
the sensing mass block is provided with a plurality of first cavities, the first cavities are symmetrically distributed about the center of the sensing mass block, the center of each first cavity is respectively provided with an anchor point, 2 cantilever beams are symmetrically distributed about the center of the first cavity in each first cavity, one end of each cantilever beam is connected with the anchor point, and the other end of each cantilever beam is connected with the sensing mass block;
the sensitivity mass block middle part is equipped with the second cavity, and zero correction structure is located the second cavity, and zero correction structure includes: the zero correction structure comprises a group of zero correction electrodes and 2 anchor points, wherein the upper zero correction electrode is connected with the upper anchor point and the sensitive mass block, the lower zero correction electrode is connected with the lower anchor point and the sensitive mass block, the upper half part and the lower half part of the zero correction structure are symmetrical about the center of the zero correction structure, and the zero correction structure is used for zero correction of the sensitive mass block;
the 2 stop structures and the 2 concave fixing structures are respectively symmetric about the center of the sensitive mass block, the concave fixing structures are connected with anchor points, one end of each stop structure is connected with the sensitive mass block, and the concave fixing structures are used for limiting and protecting the other end of each stop structure.
The accelerometer is characterized in that: 1. the zero correction structure is divided into an upper module and a lower module, each module comprises a fixed anchor point, a zero correction fixed electrode and a zero correction movable electrode, one end of the fixed electrode is connected with the anchor point, one end of the movable electrode is connected with the mass block, the fixed electrode is equidistant from the movable electrodes on two sides, an overlapping part with a certain length is formed, and the two modules are symmetrically distributed about the center of the origin of the accelerometer structure; 2. the supporting beams are cantilever beams, eight supporting beams are arranged at four corners of the movable mass block, every two supporting beams are connected together through fixed anchor points to form a group, and the four groups of beams are distributed symmetrically about the center of the origin of the structure, so that the design can well avoid interference of the X axis and the Z axis, prevent the collapse of the structure and enhance the vibration resistance of the structure; 3. by designing the concave anti-collision structure, the impact resistance of the structure can be effectively enhanced; 4. the differential detection and the closed-loop working mode are adopted, so that the signal-to-noise ratio of the accelerometer can be enhanced, the displacement of a movable structure of the accelerometer is effectively limited, the overall linearity is good, and the measurement accuracy is high; 5. the whole structure is compact in design and small in chip size.
Further, the cantilever beams in the accelerometer are 8, 4 first cavities are arranged on the sensitive mass block, the 4 first cavities are symmetrically distributed about the center of the sensitive mass block, an anchor point is arranged at the center of each first cavity, 2 cantilever beams are symmetrically distributed about the center of the first cavity in each first cavity, one end of each cantilever beam is connected with the anchor point, and the other end of each cantilever beam is connected with the sensitive mass block.
Further, the accelerometer specifically includes: 2 backstop structures and 2 spill fixed knot constructs, 2 backstop structures and 2 spill fixed knot construct respectively about the center bilateral symmetry of sensitive mass piece, and spill fixed knot constructs includes: the fixed block is connected with the anchor point, is equipped with the recess on the fixed block, and backstop structure one end is connected with sensitive quality piece, and the backstop structure other end extends to in the recess.
Further, the differential capacitance detection structure includes:
the upper detection electrode comprises a plurality of pairs of upper detection capacitors, the lower detection electrode comprises a plurality of pairs of lower detection capacitors, and each pair of upper detection capacitors comprises: the upper detection fixed comb teeth and the upper detection movable comb teeth are connected with an anchor point, one end of the upper detection fixed comb teeth is connected with the sensitive mass block, the other end of the upper detection movable comb teeth extends upwards, and the upper detection fixed comb teeth and the upper detection movable comb teeth are provided with overlapping parts in the vertical direction; each pair of lower detection capacitors comprises: detect fixed broach down, detect movable broach down, detect fixed broach one end down and be connected with the anchor point, detect movable broach one end down and be connected with sensitive quality piece, detect the fixed broach other end extension down of movable broach other end down, and detect fixed broach and detect movable broach down and have the overlap portion in vertical direction.
Further, the accelerometer closed loop feedback electrode structure comprises:
an upper force feedback electrode and a lower force feedback electrode, wherein the upper force feedback electrode comprises a plurality of pairs of upper force feedback capacitors, the lower force feedback electrode comprises a plurality of pairs of lower force feedback capacitors, and the upper force feedback capacitors comprise: upper force feedback fixed comb teeth and upper force feedback movable comb teeth; one end of the upper force feedback fixed comb teeth is connected with the anchor point, one end of the upper force feedback movable comb teeth is connected with the sensitive mass block, the other end of the upper force feedback movable comb teeth extends towards the other end of the upper force feedback fixed comb teeth, and the upper force feedback fixed comb teeth and the upper force feedback movable comb teeth are provided with overlapping parts in the vertical direction; one end of the lower force feedback fixed comb teeth is connected with the anchor point, one end of the lower force feedback movable comb teeth is connected with the sensitive mass block, the other end of the lower force feedback movable comb teeth extends downwards to the other end of the lower force feedback fixed comb teeth, and the lower force feedback fixed comb teeth and the lower force feedback movable comb teeth are provided with overlapping parts in the vertical direction.
Further, the zero correction structure includes:
two zero correction modules symmetrical about the X axis, the zero correction module comprising: anchor point, zero correction electrode include a plurality of pairs of zero correction electric capacity, and every pair of zero correction electric capacity includes: the movable comb teeth are connected with the sensing mass block, the other end of the movable comb teeth extends towards the other end of the fixed comb teeth, and the fixed comb teeth and the movable comb teeth are overlapped in the horizontal direction.
Further, the zero correction fixed comb teeth and the zero correction movable comb teeth on the two sides are equal in space.
Further, the substrate can be doped with polysilicon or glass; the sensitive device layer material is heavily doped silicon.
Further, the accelerometer is manufactured through an MEMS processing technology.
Further, the clearance between the zero correction fixed comb teeth and the zero correction movable comb teeth in the zero correction structure is thatThe overlapping length of the fixed comb teeth and the movable comb teeth in the horizontal direction is +.>Comb tooth thickness of zero correction fixed comb tooth and zero correction movable comb tooth +.>The capacitance value formed by the zero correction module is:
（1）
in the method, in the process of the invention,logarithm of zero correction module capacitance, +.>Is vacuum dielectric constant, +.>Is the relative dielectric constant of air;
the formula (1) can obtain the electrostatic force generated by the zero correction module when the comb teeth overlap length changes, namely the zero correction force is as follows:
（2）
in the method, in the process of the invention,for a fixed voltage value applied to the sensitive mass, < >>For the application of the adjustable voltage value to the zero-setting fixed comb teeth, the voltage value can be adjusted by changing +.>To change the magnitude of the zero correction force.
One or more technical schemes provided by the application have at least the following technical effects or advantages:
the invention provides an MEMS accelerometer based on zero correction, which can correct the problem of different zero output changes of the structure due to the changes of processing errors, installation errors, environmental temperature and the like by designing the accelerometer structure, eliminate the influence of the zero changes on the stability, temperature characteristics and other performances of devices, and is beneficial to keeping the high performance characteristics of the accelerometer structure in theoretical design, and meanwhile, the invention can improve the process manufacturing yield, improve the batch consistency and greatly reduce the production cost; the closed-loop working control mode is adopted, the overall linearity is good, the overall structural design is compact, the chip size is small, and the shock resistance is strong; the measurement accuracy is high.
Drawings
The accompanying drawings, which are included to provide a further understanding of embodiments of the invention and are incorporated in and constitute a part of this application, illustrate embodiments of the invention and together with the description serve to explain the principle of the invention;
FIG. 1 is a schematic structural diagram of a zero correction based MEMS accelerometer of the present application;
fig. 2 is a schematic structural view of the zero correction structure in the present application.
Detailed Description
In order that the above-recited objects, features and advantages of the present invention will be more clearly understood, a more particular description of the invention will be rendered by reference to the appended drawings and appended detailed description. In addition, the embodiments of the present application and the features in the embodiments may be combined with each other without conflicting with each other.
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, the present invention may be practiced in other ways than within the scope of the description, and the scope of the invention is therefore not limited to the specific embodiments disclosed below.
As shown in FIG. 1, the MEMS accelerometer based on zero correction according to the embodiment of the invention comprises a substrate 1, wherein the material of the substrate can be doped polysilicon or glass; the substrate 1 is provided with a thinner oxide layer, the oxide layer plays an insulating isolation and fixing role, the anchor point 2 is fixed on the substrate 1 through the oxide layer, a sensitive device layer is arranged on the oxide layer, the material of the sensitive device layer is heavily doped silicon, the sensitive device layer comprises an upper detection fixed comb tooth 4, an upper detection movable comb tooth 3, a lower detection fixed comb tooth 14, a lower detection movable comb tooth 13, an upper force feedback fixed comb tooth 5, an upper force feedback movable comb tooth 6, a lower force feedback fixed comb tooth 7, a lower force feedback movable comb tooth 8, a cantilever beam 9, a zero correction structure 10, a sensitive mass block 15, a stop structure 11 and a concave fixed structure 12, and all the structures are manufactured through MEMS processing technology.
The upper and lower detection fixed comb teeth 4 and 14 are respectively fixed on the substrate 1 through the anchor points 2, one ends of the upper and lower detection movable comb teeth 3 and 13 are connected with the sensitive mass block 15, the upper and lower detection fixed comb teeth 4 and 14 respectively form a pair of detection capacitors with the upper and lower detection movable comb teeth 3 and 13, a plurality of pairs of detection capacitors form a group of detection electrodes, the upper and lower groups of detection electrodes form an accelerometer differential capacitor detection structure, and the capacitance change caused by an acceleration signal is detected.
The upper force feedback fixed comb teeth 5 and the lower force feedback fixed comb teeth 7 are respectively fixed on the substrate 1 through the anchor points 2, one ends of the upper force feedback movable comb teeth 6 and the lower force feedback movable comb teeth 8 are connected with the sensitive mass block 15, the upper force feedback fixed comb teeth 5 and the lower force feedback fixed comb teeth 7 respectively form a pair of force feedback capacitors with the upper force feedback movable comb teeth 6 and the lower force feedback movable comb teeth 8, a plurality of pairs of force feedback capacitors form a group of force feedback electrodes, the upper force feedback electrode and the lower force feedback electrode form an accelerometer closed loop feedback electrode structure, displacement caused by acceleration signals is balanced, and the sensitive mass block is always kept at a mechanical zero position.
The zero correction structure 10, as shown in fig. 2, is divided into an upper module and a lower module, each module includes a fixed anchor point 10e, zero correction fixed comb teeth 10b and 10c, zero correction movable comb teeth 10a and 10d, the zero correction fixed comb teeth 10b and 10c are respectively fixed on the substrate 1 through the fixed anchor points 10e, one ends of the zero correction movable comb teeth 10a and 10d are connected with the sensitive mass block 15, the zero correction fixed comb teeth 10b and 10c and the zero correction movable comb teeth 10a and 10d respectively form a pair of zero correction capacitors, a plurality of pairs of zero correction capacitors form a group of zero correction electrodes, namely, a zero correction module, and the upper module and the lower module form an accelerometer zero correction structure.
One end of the stop structure 11 is connected with the sensitive mass block 15, and overload protection of the structure in the X-axis and Y-axis is realized through the concave fixing structure 12.
It should be noted that: the detection electrode, the force feedback electrode and the zero correction structure provided by the embodiment are respectively and symmetrically distributed about the center of the sensitive device, but the invention is not limited to a group of unit structures, and a plurality of groups of similar unit structures can be increased or decreased according to the requirement.
The invention adopts the closed-loop working principle that: when external acceleration signals act, the differential capacitance detection structure converts the detected acceleration signals into capacitance change signals, feedback voltage acts on the force feedback electrode structure through analysis of a subsequent interface circuit, inertia force caused by the acceleration signals is balanced, sensitive mass is kept at a mechanical zero position, corresponding voltage signals are output, and closed-loop measurement of acceleration is achieved.
The zero correction working principle of the invention is as follows:
the clearance between the fixed comb teeth and the movable comb teeth of the zero correction structure is not limited to beOverlap length of->Comb tooth thicknessThe capacitance value formed by the zero correction module is:
（1）
in the method, in the process of the invention,logarithm of zero correction module capacitance, +.>Is vacuum dielectric constant, +.>Is the relative dielectric constant of air.
The formula (1) can obtain the electrostatic force generated by the zero correction module when the comb teeth overlap length changes, namely the zero correction force is as follows:
（2）
in the method, in the process of the invention,for a fixed voltage value applied to the sensitive mass, < >>For the application of the adjustable voltage value to the zero-setting fixed comb teeth, the voltage value can be adjusted by changing +.>To change the magnitude of the zero correction force.
When the zero position output of the accelerometer structure is a non-zero value due to the changes of processing errors, installation errors, ambient temperature and the like, the zero position output is positive when the mechanical zero position of the accelerometer structure is assumed to be upwards offset, at the moment, the zero position correction upper module unit can be started, and the voltage value of the fixed comb teeth loaded on the zero position correction upper module unit is adjustedThe size of zero correction force is changed, so that the mechanical zero correction of the accelerometer structure is completed, and zero output is zero; when the mechanical zero position of the accelerometer structure shifts downwards, the zero position output is negative, the zero position correction lower module unit can be started at the moment, and the voltage value of the fixed comb teeth loaded under the zero position correction is adjusted>The zero correction force is changed, so that the mechanical zero correction of the accelerometer structure is completed, zero output is zero, and the zero correction of the accelerometer structure is realized.
While preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. It is therefore intended that the following claims be interpreted as including the preferred embodiments and all such alterations and modifications as fall within the scope of the invention.
It will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention also include such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.
Claims (8)
1. A zero correction based MEMS accelerometer, the accelerometer comprising:
the substrate is equipped with the oxide layer on the substrate, and a plurality of anchor points are fixed on the substrate through the oxide layer, are equipped with sensitive device layer on the oxide layer, and sensitive device layer includes: the accelerometer comprises a differential capacitance detection structure, an accelerometer closed-loop feedback electrode structure, a plurality of cantilever beams, a zero correction structure, a sensitive mass block, 2 stop structures and 2 concave fixing structures;
the differential capacitance detection structure is connected with the anchor point and the sensitive mass block and is used for detecting capacitance change caused by an acceleration signal; the accelerometer closed loop feedback electrode structure is connected with the anchor point and the sensitive mass block and is used for balancing displacement caused by an acceleration signal so as to keep the sensitive mass block at a mechanical zero position;
the sensing mass block is provided with a plurality of first cavities, the first cavities are symmetrically distributed about the center of the sensing mass block, the center of each first cavity is respectively provided with an anchor point, 2 cantilever beams are symmetrically distributed about the center of the first cavity in each first cavity, one end of each cantilever beam is connected with the anchor point, and the other end of each cantilever beam is connected with the sensing mass block;
the sensitivity mass block middle part is equipped with the second cavity, and zero correction structure is located the second cavity, and zero correction structure includes: the zero correction structure comprises a group of zero correction electrodes and 2 anchor points, wherein the upper zero correction electrode is connected with the upper anchor point and the sensitive mass block, the lower zero correction electrode is connected with the lower anchor point and the sensitive mass block, the upper half part and the lower half part of the zero correction structure are symmetrical about the center of the zero correction structure, and the zero correction structure is used for zero correction of the sensitive mass block;
the 2 stop structures and the 2 concave fixing structures are respectively symmetric left and right about the center of the sensitive mass block, the concave fixing structures are connected with anchor points, one end of each stop structure is connected with the sensitive mass block, and the concave fixing structures are used for limiting and protecting the other end of each stop structure;
the differential capacitance detection structure includes: the upper detection electrode comprises a plurality of pairs of upper detection capacitors, the lower detection electrode comprises a plurality of pairs of lower detection capacitors, and each pair of upper detection capacitors comprises: the upper detection fixed comb teeth and the upper detection movable comb teeth are connected with an anchor point, one end of the upper detection fixed comb teeth is connected with the sensitive mass block, the other end of the upper detection movable comb teeth extends upwards, and the upper detection fixed comb teeth and the upper detection movable comb teeth are provided with overlapping parts in the vertical direction; each pair of lower detection capacitors comprises: the lower detection fixed comb teeth and the lower detection movable comb teeth are connected with an anchor point, one end of the lower detection fixed comb teeth is connected with the sensitive mass block, the other end of the lower detection movable comb teeth extends downwards, and the lower detection fixed comb teeth and the lower detection movable comb teeth are provided with overlapping parts in the vertical direction;
the zero correction structure includes: two zero correction modules symmetrical about the X axis, the zero correction module comprising: anchor point, zero correction electrode include a plurality of pairs of zero correction electric capacity, and every pair of zero correction electric capacity includes: the movable comb teeth are connected with the sensing mass block, the other end of the movable comb teeth extends towards the other end of the fixed comb teeth, and the fixed comb teeth and the movable comb teeth are overlapped in the horizontal direction.
2. The zero correction-based MEMS accelerometer of claim 1, wherein the number of cantilever beams in the accelerometer is 8, 4 first cavities are arranged on the sensitive mass block, the 4 first cavities are symmetrically distributed around the center of the sensitive mass block, an anchor point is respectively arranged at the center of each first cavity, 2 cantilever beams are symmetrically distributed around the center of the first cavity in each first cavity, one end of each cantilever beam is connected with the anchor point, and the other end of each cantilever beam is connected with the sensitive mass block.
3. The zero correction based MEMS accelerometer of claim 1, wherein the accelerometer specifically comprises: 2 backstop structures and 2 spill fixed knot constructs, 2 backstop structures and 2 spill fixed knot construct respectively about the center bilateral symmetry of sensitive mass piece, and spill fixed knot constructs includes: the fixed block is connected with the anchor point, is equipped with the recess on the fixed block, and backstop structure one end is connected with sensitive quality piece, and the backstop structure other end extends to in the recess.
4. The zero correction based MEMS accelerometer of claim 1, wherein the accelerometer closed loop feedback electrode structure comprises:
an upper force feedback electrode and a lower force feedback electrode, wherein the upper force feedback electrode comprises a plurality of pairs of upper force feedback capacitors, the lower force feedback electrode comprises a plurality of pairs of lower force feedback capacitors, and the upper force feedback capacitors comprise: upper force feedback fixed comb teeth and upper force feedback movable comb teeth; one end of the upper force feedback fixed comb teeth is connected with the anchor point, one end of the upper force feedback movable comb teeth is connected with the sensitive mass block, the other end of the upper force feedback movable comb teeth extends towards the other end of the upper force feedback fixed comb teeth, and the upper force feedback fixed comb teeth and the upper force feedback movable comb teeth are provided with overlapping parts in the vertical direction; one end of the lower force feedback fixed comb teeth is connected with the anchor point, one end of the lower force feedback movable comb teeth is connected with the sensitive mass block, the other end of the lower force feedback movable comb teeth extends downwards to the other end of the lower force feedback fixed comb teeth, and the lower force feedback fixed comb teeth and the lower force feedback movable comb teeth are provided with overlapping parts in the vertical direction.
5. The zero-correction based MEMS accelerometer of claim 1, wherein the zero-correction fixed comb teeth are equidistant from the two-sided zero-correction movable comb teeth.
6. The zero correction based MEMS accelerometer of claim 1, wherein the substrate is doped with polysilicon or glass; the sensitive device layer material is heavily doped silicon.
7. The zero correction based MEMS accelerometer of claim 1, wherein the accelerometer is fabricated by a MEMS process.
8. The zero-correction-based MEMS accelerometer of claim 1, wherein the zero-correction fixed comb teeth and the zero-correction movable comb teeth in the zero-correction structure have a gap ofThe overlapping length of the fixed comb teeth and the movable comb teeth in the horizontal direction is +.>Comb tooth thickness of zero correction fixed comb tooth and zero correction movable comb tooth +.>The capacitance value formed by the zero correction module is:
（1）
in the method, in the process of the invention,logarithm of zero correction module capacitance, +.>Is vacuum dielectric constant, +.>Is the relative dielectric constant of air;
the formula (1) can obtain the electrostatic force generated by the zero correction module when the comb teeth overlap length changes, namely the zero correction force is as follows:
（2）
in the method, in the process of the invention,for a fixed voltage value applied to the sensitive mass, < >>For the application of the adjustable voltage value to the zero-setting fixed comb teeth, the voltage value can be adjusted by changing +.>To change the magnitude of the zero correction force.
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| CN114088976B (en) * | 2022-01-24 | 2022-04-12 | 成都华托微纳智能传感科技有限公司 | Comb gap adjustable MEMS accelerometer |
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| CN117705199B (en) * | 2024-02-05 | 2024-05-03 | 四川芯音科技有限公司 | High-performance MEMS temperature and humidity sensor |
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Citations (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR19990073891A (en) * | 1998-03-04 | 1999-10-05 | 윤종용 | Capacity Change Micro Accelerometer |
| US6386032B1 (en) * | 1999-08-26 | 2002-05-14 | Analog Devices Imi, Inc. | Micro-machined accelerometer with improved transfer characteristics |
| CN1401080A (en) * | 2000-01-13 | 2003-03-05 | Bae系统公共有限公司 | Accelerometer |
| JP2013096801A (en) * | 2011-10-31 | 2013-05-20 | Mitsubishi Precision Co Ltd | Vibrating structure gyroscope with excellent output stability |
| CN103954795A (en) * | 2014-04-30 | 2014-07-30 | 中国科学院地质与地球物理研究所 | MEMS accelerometer capable of being engineered |
| CN103954793A (en) * | 2014-04-30 | 2014-07-30 | 中国科学院地质与地球物理研究所 | MEMS accelerometer |
| JP2014178195A (en) * | 2013-03-14 | 2014-09-25 | Mitsubishi Precision Co Ltd | Vibration type gyro having bias correcting function |
| CN106597016A (en) * | 2016-12-22 | 2017-04-26 | 四川纳杰微电子技术有限公司 | Capacitive MEMS dual-axis accelerometer |
| CN106970244A (en) * | 2017-04-18 | 2017-07-21 | 四川知微传感技术有限公司 | Multi-range MEMS closed-loop accelerometer |
| CN108507555A (en) * | 2018-04-16 | 2018-09-07 | 四川知微传感技术有限公司 | MEMS (micro-electromechanical system) micro-mechanical fully-decoupled closed-loop gyroscope |
| CN207908539U (en) * | 2017-12-04 | 2018-09-25 | 成都信息工程大学 | A kind of comb capacitance type 3 axis MEMS acceleration transducer |
| CN109085382A (en) * | 2018-06-29 | 2018-12-25 | 华中科技大学 | A kind of acceleration sensitive mechanism based on mechanical Meta Materials and compound sensitivity micro-mechanical accelerometer |
| CN109642915A (en) * | 2016-07-27 | 2019-04-16 | 卢米达因科技公司 | Accelerometer in complex vibration plane |
| CN209746002U (en) * | 2019-05-29 | 2019-12-06 | 四川知微传感技术有限公司 | micromechanical MEMS accelerometer based on zero correction |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6651500B2 (en) * | 2001-10-03 | 2003-11-25 | Litton Systems, Inc. | Micromachined silicon tuned counterbalanced accelerometer-gyro with quadrature nulling |
| KR100513346B1 (en) * | 2003-12-20 | 2005-09-07 | 삼성전기주식회사 | A capacitance accelerometer having a compensation elctrode |
-
2019
- 2019-05-29 CN CN201910458116.2A patent/CN110095632B/en active Active
Patent Citations (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR19990073891A (en) * | 1998-03-04 | 1999-10-05 | 윤종용 | Capacity Change Micro Accelerometer |
| US6386032B1 (en) * | 1999-08-26 | 2002-05-14 | Analog Devices Imi, Inc. | Micro-machined accelerometer with improved transfer characteristics |
| CN1401080A (en) * | 2000-01-13 | 2003-03-05 | Bae系统公共有限公司 | Accelerometer |
| JP2013096801A (en) * | 2011-10-31 | 2013-05-20 | Mitsubishi Precision Co Ltd | Vibrating structure gyroscope with excellent output stability |
| JP2014178195A (en) * | 2013-03-14 | 2014-09-25 | Mitsubishi Precision Co Ltd | Vibration type gyro having bias correcting function |
| CN103954793A (en) * | 2014-04-30 | 2014-07-30 | 中国科学院地质与地球物理研究所 | MEMS accelerometer |
| CN103954795A (en) * | 2014-04-30 | 2014-07-30 | 中国科学院地质与地球物理研究所 | MEMS accelerometer capable of being engineered |
| CN109642915A (en) * | 2016-07-27 | 2019-04-16 | 卢米达因科技公司 | Accelerometer in complex vibration plane |
| CN106597016A (en) * | 2016-12-22 | 2017-04-26 | 四川纳杰微电子技术有限公司 | Capacitive MEMS dual-axis accelerometer |
| CN106970244A (en) * | 2017-04-18 | 2017-07-21 | 四川知微传感技术有限公司 | Multi-range MEMS closed-loop accelerometer |
| CN207908539U (en) * | 2017-12-04 | 2018-09-25 | 成都信息工程大学 | A kind of comb capacitance type 3 axis MEMS acceleration transducer |
| CN108507555A (en) * | 2018-04-16 | 2018-09-07 | 四川知微传感技术有限公司 | MEMS (micro-electromechanical system) micro-mechanical fully-decoupled closed-loop gyroscope |
| CN109085382A (en) * | 2018-06-29 | 2018-12-25 | 华中科技大学 | A kind of acceleration sensitive mechanism based on mechanical Meta Materials and compound sensitivity micro-mechanical accelerometer |
| CN209746002U (en) * | 2019-05-29 | 2019-12-06 | 四川知微传感技术有限公司 | micromechanical MEMS accelerometer based on zero correction |
Non-Patent Citations (1)
| Title |
|---|
| 变面积结构微机械电容式加速度传感器;李宝清, 陆德仁, 王渭源;中国工程科学;20000229(02);全文 * |
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