CN116773058A - MEMS silicon pressure sensor chip and sensor with PT resistance - Google Patents
MEMS silicon pressure sensor chip and sensor with PT resistance Download PDFInfo
- Publication number
- CN116773058A CN116773058A CN202310741045.3A CN202310741045A CN116773058A CN 116773058 A CN116773058 A CN 116773058A CN 202310741045 A CN202310741045 A CN 202310741045A CN 116773058 A CN116773058 A CN 116773058A
- Authority
- CN
- China
- Prior art keywords
- pressure sensor
- resistor
- sensor chip
- mems silicon
- silicon pressure
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B81—MICROSTRUCTURAL TECHNOLOGY
- B81B—MICROSTRUCTURAL DEVICES OR SYSTEMS, e.g. MICROMECHANICAL DEVICES
- B81B7/00—Microstructural systems; Auxiliary parts of microstructural devices or systems
- B81B7/02—Microstructural systems; Auxiliary parts of microstructural devices or systems containing distinct electrical or optical devices of particular relevance for their function, e.g. microelectro-mechanical systems [MEMS]
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L1/00—Measuring force or stress, in general
- G01L1/18—Measuring force or stress, in general using properties of piezo-resistive materials, i.e. materials of which the ohmic resistance varies according to changes in magnitude or direction of force applied to the material
Landscapes
- Engineering & Computer Science (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Measuring Fluid Pressure (AREA)
- Pressure Sensors (AREA)
Abstract
The invention discloses a MEMS silicon pressure sensor chip with PT resistor and a sensor, the chip comprises: a pressure sensitive membrane; 2N discontinuous concave areas which are annularly and uniformly arranged are etched on the front surface of the pressure-sensitive membrane; n straight beams are formed by adjacent gaps of 2N discontinuous concave areas; a central circular island is formed in the middle area surrounded by the 2N discontinuous concave areas 3; n is a positive integer; four piezoresistors are symmetrically arranged on the same straight beam; the central circular island 4 is integrated with a PT resistor. The invention adopts the mode of integrating PT resistor on the chip front structure, the temperature response is real-time and rapid, the result is real, the temperature compensation problem of the sensor under the rapid temperature change can be solved, and the invention is beneficial to improving the performance of the MEMS silicon pressure sensor.
Description
Technical Field
The invention relates to the technical field of sensor chips, in particular to a MEMS silicon pressure sensor chip with PT resistance and a sensor.
Background
The MEMS silicon pressure sensor is a silicon cup-shaped structure made of monocrystalline silicon by MEMS processing technology, and referring to fig. 1, four equivalent semiconductor resistors are formed on the front surface of a thin film by doping or ion implantation process, and four piezoresistors form a wheatstone bridge circuit by metal connecting wires.
When external pressure is applied, the stress of the piezoresistor area can change, so that the bridge loses balance output voltage signals due to the change of the resistance value of the resistor. However, due to the inherent properties of the semiconductor material, the output of the sensor is affected by temperature variations, resulting in temperature drift that seriously affects the measurement accuracy of the sensor.
The traditional temperature compensation scheme comprises hardware compensation and software compensation, wherein the hardware compensation is generally difficult to apply to occasions with high compensation precision requirements, difficult to debug and poor in flexibility. The software compensation is to correct zero drift, sensitivity drift and nonlinearity problems of the sensor by using a compensation algorithm and a mathematical method according to calibration data, and the sensor processing circuit is required to be externally connected with a temperature sensor to detect the working environment temperature of the chip. The traditional external temperature sensor mode has larger hysteresis for temperature response under the use environment of rapid temperature change, and meanwhile, the actual temperature of the chip can not be accurately reflected due to position deviation.
Disclosure of Invention
In view of the above, the invention aims to solve the temperature compensation problem of the sensor under the rapid temperature change and improve the performance of the MEMS silicon pressure sensor; a MEMS silicon pressure sensor chip with PT resistor and sensor are provided.
In order to achieve the above purpose, the present invention provides the following technical solutions:
in a first aspect, an embodiment of the present invention provides a MEMS silicon pressure sensor chip with PT resistance; comprising the following steps: a pressure sensitive membrane;
2N discontinuous concave areas which are annularly and uniformly arranged are etched on the front surface of the pressure-sensitive membrane; n straight beams are formed by adjacent gaps of 2N discontinuous concave areas; a central circular island is formed in the middle area surrounded by the 2N discontinuous concave areas; n is a positive integer;
four piezoresistors are symmetrically arranged on the same straight beam;
the central circular island is integrated with a PT resistor.
Further, the four piezoresistors are divided into two groups, wherein the first group is a longitudinal resistor; the second group is a transverse resistor; the resistances of the first set are mirror symmetric with the resistances of the second set.
Further, the four piezoresistors are arranged along the 110 crystal direction.
Further, the piezoresistor is of a bending structure.
Further, the varistor includes: two varistor strips and a heavily doped connecting strip; two ends of the heavily doped connecting strip are respectively correspondingly connected with one end of one piezoresistor strip;
the other end of the piezoresistor strip is connected with a metal lead through a heavily doped connecting block.
Further, the PT resistor is of an arc-shaped grid wire structure.
Further, the straight beam is a stress concentration area, and is obtained through ansys finite element simulation.
Further, when N is greater than 1, the metal lead of the PT resistor is disposed on the first beam and the varistor is disposed on the second straight beam.
Further, the first straight beam and the second straight beam are perpendicular to each other.
In a second aspect, an embodiment of the present invention further provides a sensor, including any one of the MEMS silicon pressure sensor chips with PT resistor in the first aspect.
The invention has the advantages and effects that:
1. in the invention, the front side of the pressure-sensitive diaphragm is etched with a concave area; the adjacent gaps of the concave areas form straight beams; the central area surrounded by the concave areas forms a central circular island, a Liang Modao structure of a circular diaphragm is formed, positive stress concentration and negative stress concentration are respectively arranged on the beam near the edge of the diaphragm and the edge of the island, and the sensor chip is ensured to have high enough output by arranging the piezoresistor at the stress concentration position. Under the condition of reducing the chip volume and not affecting the linearity, the output sensitivity of the sensor is improved by utilizing the high stress concentration area on the beam structure. By applying the beam film island structure, on one hand, the local reinforcement effect of the film is realized, and the deflection of the film can be greatly reduced, so that the nonlinear error is reduced; on the other hand, the linear bending stress is concentrated on the narrow beam, ensuring high sensitivity of the sensor.
2. The invention can optimize the structural size on the premise of ensuring the symmetrical arrangement of the piezoresistors, combines the high stress concentration range on the chip beam, designs the number of the piezoresistor segments and the specific size, maximally utilizes the stress concentration area, and maximizes the output of the sensor chip.
3. The PT resistor is integrated on the front island structure of the beam film island structure chip, when the chip is loaded, the membrane deforms, and the island structure increases the local rigidity of the membrane, so that the PT resistor integrated on the front island is less in bending deformation. Through optimizing the arrangement mode of the platinum resistor, the longitudinal strain of the PT resistor can be effectively reduced when the diaphragm is loaded by adopting the arc-shaped grid wire structure, so that the influence of the deformation of the diaphragm on the PT resistor output is less, and the temperature change can be truly detected. Meanwhile, the PT resistor is integrated on the chip body, so that the integrated PT resistor can accurately reflect the real-time temperature of the sensor chip, and the accuracy of the input data of the subsequent temperature compensation is ensured.
Drawings
FIG. 1 is a schematic diagram of a prior art Wheatstone bridge;
FIG. 2 is a schematic diagram of a MEMS silicon pressure sensor chip with PT resistor according to the present invention;
FIG. 3 is a schematic diagram of a varistor according to the present invention;
in the figure: 1. a metal lead; 2. a piezoresistor; 3. a concave region; 4. a central circular island; 5. a straight beam; 6. PT resistance; 7. a stress concentration region; 8. a pressure sensitive membrane; 9. heavily doped connecting strips; 10. a varistor strip; 11. the connection block is heavily doped.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Example 1:
referring to fig. 2, the present invention provides a MEMS silicon pressure sensor chip with PT resistance, comprising: a pressure sensitive membrane 8;
2N discontinuous concave areas 3 which are annularly and uniformly arranged are etched on the front surface of the pressure-sensitive membrane 8; n straight beams 5 are formed by adjacent gaps of 2N discontinuous concave areas 3; a central circular island 4 is formed in the middle area surrounded by the 2N discontinuous concave areas 3; n is a positive integer. For example, in fig. 2, n=2, with four discontinuous recesses 3, adjacent gaps form two straight beams 5.
In this embodiment, the etching method may use wet etching with KOH or TMAH; the pressure-sensitive diaphragm is not only a substrate of the piezoresistor, but also a receptor for external stress, so that the pressure-sensitive diaphragm is a core part of the pressure sensing element; the pressure-sensitive membrane can be made of an SOI silicon wafer, an isolation layer and a stability enhancing layer are sequentially deposited on the surface of the pressure-sensitive membrane, and the isolation layer is made by thermal oxygen growth or by a chemical vapor deposition method; the embodiments of the present disclosure are not limited in any way.
Four piezoresistors 2 are symmetrically arranged on the same straight beam 5; the piezoresistor is a P-type polycrystalline silicon nano-film resistor, and the central circular island 4 is integrated with a PT resistor 6.
In the present embodiment, the four piezoresistors 2 are divided into two groups, wherein the first group is the longitudinal resistor R 1 、R 3 The method comprises the steps of carrying out a first treatment on the surface of the The second group is a transverse resistor R 2 、R 4 The method comprises the steps of carrying out a first treatment on the surface of the The resistors of the first group are mirror symmetrical with the resistors of the second group; when external load is applied to the pressure-sensitive membrane, the resistor R 1 、R 3 Resistance value of (2) becomes larger, resistance R 2 、R 4 The method comprises the steps of carrying out a first treatment on the surface of the The resistance of (c) becomes smaller.
In this embodiment, the area of the straight beam 5 near the edge of the pressure-sensitive membrane 8 has the largest positive longitudinal and transverse stress difference, and the area of the straight beam 5 near the central circular island 4 has the negative longitudinal and transverse stress difference, so that the high sensitivity of the pressure-sensitive chip is ensured. The metal lead 1 arranges the 4 piezoresistors 2 into a fully open loop Wheatstone bridge circuit structure, and establishes electrical connection with a sensor circuit to obtain sensor related test information.
In this embodiment, the four piezoresistors 2 are arranged along the 110 crystal direction. The space grid of atoms arranged regularly in the crystal is called a crystal lattice, and the crystal orientation refers to the basic characteristic of the crystal that the crystal has directivity, and specifically comprises three indexes of 110, 011 and 101; the crystal properties are different along different directions of the lattice.
In this embodiment, the piezoresistor 2 is a bending structure; the transverse effect at the bending position of the piezoresistor strip can be avoided.
Referring to fig. 3, the varistor 2 includes: two varistor strips 10 and a heavily doped connecting strip 9; two ends of the heavily doped connecting strip 9 are respectively correspondingly connected with one end of a piezoresistor strip 10; the heavy doping mode adopts P type heavy doping ion implantation, and the doping source is boron compound; if N-type heavy doping ion implantation is adopted, the doping source is a compound of phosphorus or arsenic. The other end of the varistor strip 10 is connected to a metal lead by means of a heavily doped connecting block 11.
As shown in fig. 2, the PT resistor 6 has a circular arc type grid wire structure. The output resistance change caused by the deformation of the pressure-sensitive membrane when the pressure-sensitive chip works can be effectively avoided, and the accuracy of the PT resistance test temperature is ensured.
In this embodiment, the straight beam is a stress concentration region, which is obtained through ansys finite element simulation. When an external load acts on the pressure sensitive diaphragm, a stress concentration region occurs near the edge of the diaphragm in order to make maximum use of the stress concentration region. The ANSYS program provides the functions of dragging, extending, rotating, moving, extending, and copying the primitives of the mockup when creating the mockup using ANSYS.
The ANSYS program can divide the complex model directly, and avoids the trouble caused by unmatched grids of all parts when a user divides and assembles all parts respectively. The self-adaptive grid division is that after the entity model with boundary conditions is generated, a user instruction program automatically generates a finite element grid, analyzes and estimates the discrete error of the grid, redefines the size of the grid, and analyzes and calculates and estimates the discrete error of the grid again until the error is lower than a user-defined value or the user-defined solving frequency is reached.
In this embodiment, when N is greater than 1, the metal lead 1 of the PT resistor is disposed on the first beam and the varistor 2 is disposed on the second straight beam. The first straight beam and the second straight beam are perpendicular to each other; namely, symmetry can be satisfied for each other as axes, and the degree of performance interference caused by objective factors can be reduced as much as possible; for example, the resistance heating tends to have the same effect on the ambient temperature diffusion due to the same structure.
Example 2:
based on the same inventive concept, the invention also provides a sensor, comprising the MEMS silicon pressure sensor chip with PT resistor, the silicon substrate, the glass substrate and the bonding pad in the embodiment 1;
a silicon substrate is bonded on the glass substrate, and a vacuum chamber is arranged on the silicon substrate; the glass substrate and the silicon substrate are bonded by adopting an anode, and the silicon substrate is made of an SOI material;
the glass substrate and the silicon substrate are bonded by adopting an anode, sodium ions in the glass become a movable state when the glass is heated to high temperature, the sodium ions leave the contact surface under the drive of a high-voltage electric field, and covalent bonds are generated between Si in the glass substrate and Si in the silicon substrate near the contact surface, so that the tight connection between the glass substrate and the silicon substrate is realized, and the chip is sealed on the glass substrate by adopting a bonding mode, so that the vacuum degree and the sealing strength of the vacuum chamber are greatly enhanced.
A bonding pad is connected at the turning part of the PT resistor and the metal lead of the piezoresistor in the chip; the metal leads may be copper wires.
The sensor provided by the invention has the advantages of simple structure, high stability and universality and wide application prospect.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles disclosed herein.
Claims (10)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310741045.3A CN116773058A (en) | 2023-06-21 | 2023-06-21 | MEMS silicon pressure sensor chip and sensor with PT resistance |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310741045.3A CN116773058A (en) | 2023-06-21 | 2023-06-21 | MEMS silicon pressure sensor chip and sensor with PT resistance |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116773058A true CN116773058A (en) | 2023-09-19 |
Family
ID=87994286
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310741045.3A Pending CN116773058A (en) | 2023-06-21 | 2023-06-21 | MEMS silicon pressure sensor chip and sensor with PT resistance |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116773058A (en) |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2007139695A2 (en) * | 2006-05-24 | 2007-12-06 | Vladimir Vaganov | Force input control device and method of fabrication |
| CN102636298A (en) * | 2012-03-16 | 2012-08-15 | 西安交通大学 | Beam-film four-land structured micro-pressure high-overload sensor chip |
| CN103487178A (en) * | 2013-09-16 | 2014-01-01 | 沈阳仪表科学研究院有限公司 | High-power overload 1KPa silicon micropressure sensor chip and manufacturing method |
| CN109708786A (en) * | 2018-12-07 | 2019-05-03 | 苏州长风航空电子有限公司 | A kind of dual stress concentrating structure micro-pressure sensor core and preparation method |
| CN212693124U (en) * | 2020-09-21 | 2021-03-12 | 明石创新(烟台)微纳传感技术研究院有限公司 | Novel beam membrane island structure high pressure sensor |
| CN113063530A (en) * | 2021-03-30 | 2021-07-02 | 成都凯天电子股份有限公司 | MEMS silicon piezoresistive pressure sensor and preparation method thereof |
| CN113138049A (en) * | 2021-03-18 | 2021-07-20 | 宁波大学 | Integrated micro-nano sensor for water body temperature and salt depth detection and manufacturing method thereof |
| CN113295306A (en) * | 2021-04-27 | 2021-08-24 | 西安交通大学 | Piezoresistive beam stress concentration micro-pressure sensor chip and preparation method thereof |
| CN115285929A (en) * | 2022-07-22 | 2022-11-04 | 中电科技集团重庆声光电有限公司 | Micro-differential pressure type MEMS pressure sensor pressure-sensitive chip and preparation method thereof |
-
2023
- 2023-06-21 CN CN202310741045.3A patent/CN116773058A/en active Pending
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2007139695A2 (en) * | 2006-05-24 | 2007-12-06 | Vladimir Vaganov | Force input control device and method of fabrication |
| CN102636298A (en) * | 2012-03-16 | 2012-08-15 | 西安交通大学 | Beam-film four-land structured micro-pressure high-overload sensor chip |
| CN103487178A (en) * | 2013-09-16 | 2014-01-01 | 沈阳仪表科学研究院有限公司 | High-power overload 1KPa silicon micropressure sensor chip and manufacturing method |
| CN109708786A (en) * | 2018-12-07 | 2019-05-03 | 苏州长风航空电子有限公司 | A kind of dual stress concentrating structure micro-pressure sensor core and preparation method |
| CN212693124U (en) * | 2020-09-21 | 2021-03-12 | 明石创新(烟台)微纳传感技术研究院有限公司 | Novel beam membrane island structure high pressure sensor |
| CN113138049A (en) * | 2021-03-18 | 2021-07-20 | 宁波大学 | Integrated micro-nano sensor for water body temperature and salt depth detection and manufacturing method thereof |
| CN113063530A (en) * | 2021-03-30 | 2021-07-02 | 成都凯天电子股份有限公司 | MEMS silicon piezoresistive pressure sensor and preparation method thereof |
| CN113295306A (en) * | 2021-04-27 | 2021-08-24 | 西安交通大学 | Piezoresistive beam stress concentration micro-pressure sensor chip and preparation method thereof |
| CN115285929A (en) * | 2022-07-22 | 2022-11-04 | 中电科技集团重庆声光电有限公司 | Micro-differential pressure type MEMS pressure sensor pressure-sensitive chip and preparation method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111620295B (en) | A micro pressure detection pressure sensor and its measuring device | |
| CN105241369B (en) | MEMS strain gauge chip and manufacturing process thereof | |
| KR20040079323A (en) | Semiconductor pressure sensor having diaphragm | |
| CN101271028A (en) | Pressure sensor chip and method based on silicon-silicon bonding and silicon-on-insulator | |
| CN113639902B (en) | Pressure sensor and manufacturing method thereof | |
| CN113758613B (en) | SOI-based resistance center placed piezoresistive pressure sensor | |
| CN119880241B (en) | Linear Liang Shuangdao-structure high-pressure sensor chip with stress hole and preparation method | |
| CN113218544B (en) | Micro-pressure sensor chip with stress concentration structure and preparation method thereof | |
| CN111498795B (en) | Pressure sensor chip with isolation groove array structure and preparation method thereof | |
| CN105716750A (en) | MEMS piezoresistive pressure sensor and production method thereof | |
| Tang et al. | Structure design and optimization of SOI high-temperature pressure sensor chip | |
| CN112284607A (en) | Cross island high-temperature-resistant corrosion-resistant pressure sensor chip and preparation method thereof | |
| CN114705332B (en) | High-sensitivity low-nonlinearity pressure sensor and preparation method thereof | |
| CN113465791B (en) | Resonant pressure sensor and preparation method thereof | |
| CN118583363A (en) | A pressure sensor with an on-chip temperature measuring element and implementation method thereof | |
| WO2013020275A1 (en) | Manufacturing method of mems piezoresistive pressure chip and sensor | |
| CN112607701A (en) | MEMS pressure chip and preparation method thereof | |
| CN204718717U (en) | The MEMS pressure sensor of silicon island membrane structure | |
| CN116773058A (en) | MEMS silicon pressure sensor chip and sensor with PT resistance | |
| CN113390552B (en) | A pressure sensor and a method for manufacturing the same | |
| CN115326249B (en) | A MEMS pressure sensor and a manufacturing method thereof | |
| CN115824468A (en) | Small-range high-sensitivity pressure sensor chip based on SOI and preparation method | |
| CN220056358U (en) | Ultralow pressure core body with stress buffer groove | |
| CN118936694A (en) | A high consistency MEMS pressure sensor and preparation method thereof | |
| JPH0554709B2 (en) |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |