CN202420729U - Capacitive pressure sensor - Google Patents
Capacitive pressure sensor Download PDFInfo
- Publication number
- CN202420729U CN202420729U CN2012200559661U CN201220055966U CN202420729U CN 202420729 U CN202420729 U CN 202420729U CN 2012200559661 U CN2012200559661 U CN 2012200559661U CN 201220055966 U CN201220055966 U CN 201220055966U CN 202420729 U CN202420729 U CN 202420729U
- Authority
- CN
- China
- Prior art keywords
- capacitance
- pressure
- sensitive film
- polysilicon layer
- pressure transducer
- 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.)
- Withdrawn - After Issue
Links
Images
Landscapes
- Measuring Fluid Pressure (AREA)
Abstract
The utility model discloses a capacitive pressure sensor, which comprises a substrate, a lower polar plate, a pressure-sensitive film, a capacitance gap and anchor points, wherein the lower polar plate is covered on the substrate; the pressure-sensitive film is opposite to the lower polar plate; the capacitance gap is positioned between the lower polar plate and the pressure-sensitive film; the anchor points surround the periphery of the capacitance gap, and are used for supporting the pressure-sensitive film; the pressure-sensitive film and the lower polar plate are taken as two electrodes of the capacitive pressure sensor respectively; the capacitive pressure sensor further comprises a first pressure welding point and a second pressure welding point which are deposited on the lower polar plate and the pressure-sensitive film respectively; the pressure-sensitive film is provided with an air guide hole for communicating the capacitance gap with external gas; and the air guide hole is sealed by metal, so that the capacitance gap becomes an enclosed vacuum cavity finally. The capacitive pressure sensor does not generate large parasitic capacitance, is simple in process, low in cost and high in manufacturability, and is suitable for large-scale production.
Description
Technical field
The utility model relates to a kind of capacitance pressure transducer,, belongs to MEMS (MEMS) sensor field.
Background technology
Pressure transducer is the transducer that pressure signal is converted into electrical signal, is the important component part in the business-like sensor.The same with other electronic devices and components, along with the increase that reaches demand of popularizing of using, the development trend of pressure transducer is that volume is little, highly sensitive, power consumption is little, price is low, reliability is high.
And the MEMS technology is just promoting the change that semiconductor circle " surmounts Moore's Law " at present, has obtained swift and violent development at home and abroad.The radio tube epoch of yesterday are just being passed through in the world, cross over the MEMS epoch that the present solid electronic epoch get into tomorrow.MEMS is as a new and high technology of high speed development in recent years, and it adopts advanced semiconductor preparing process, realizes the MEMS preparation of devices in batches.Compare with corresponding conventional pressure sensor, adopt the pressure transducer of MEMS technology preparation obvious advantages to be arranged at aspects such as volume, power consumption, weight and prices.So the pressure transducer that adopts advanced MEMS fabrication techniques is the technological development direction of following main flow.
According to the difference of principle of work, pressure transducer mainly is divided into pressure resistance type, condenser type and piezoelectric type etc.Advantages such as at present, piezoresistive pressure sensor is because the compatible height of its manufacturing process and semiconductor technology, and manufacturing process is simple, and interface circuit is simple are the mainstream technologys of present pressure transducer.Shortcomings such as but piezoresistive pressure sensor but has temperature characterisitic poor, and sensitivity is low, and power consumption is big, and be not suitable for some low-power consumption and the high application of precision.
And, add that the size of capacitance pressure transducer, own is little along with the maturation of MEMS processing technology, and cost is low, and plurality of advantages such as good temp characteristic, precision are high, low in energy consumption makes the capacitance pressure transducer, technology obtain increasing concern.
Capacitance pressure transducer, is the transducer that pressure signal is become capacitance signal.Its principle of work is a variable capacitance; Wherein one or two electrode of variable capacitance is formed by pressure sensitive film; Under the ambient pressure effect, produce distortion as the pressure sensitive film of capacitance electrode and cause capacitance gap to change, thereby cause capacitance to change.The change of this capacitance becomes voltage or current signal through the processing of subsequent conditioning circuit.
There are some companies to adopt the silicon SOI material on the dielectric substrate to make capacitance pressure transducer, abroad.Its main thought is to empty the vacuum gap that the SOI buried silicon oxide layer forms electric capacity through corrosion, and with the upper and lower battery lead plate of SOI material silicon materials up and down as electric capacity.This manufacturing approach has avoided above-mentioned polysilicon to do a series of problems of pressure sensitive film, thereby has improved the manufacturability of device, has improved yield.But this manufacturing approach utilizes the buried silicon oxide layer of SOI as sacrifice layer, so more process technology limit is arranged.At first, the thickness of monox is the thickness of final capacitance gap, and the common thinner thickness of SOI buried silicon oxide layer has so just limited some design flexibilitys of capacitance pressure transducer; Secondly and since the SOI buried silicon oxide layer not corrosion so whole long corrosion releasing sacrificial layer silicon nitride process can only be through time control, thereby make the difficult control of technology and then cause the resulting devices discreteness bigger from not stopping the border, reduced yield rate; Once more, this technology still need form the release aperture sealing technology of vacuum chamber, has increased process complexity.So,, do not become the main flow technology of industry member though this manufacturing approach has part company to adopt.
For addressing the above problem; Part company adopts in advance and forms the mode that groove is used as capacitance gap in surface of silicon, through the wafer scale silocon-silicon linkage technology, two silicon substrates is bonded together; Two silicon substrates are made capacitance pressure transducer, respectively as two electrodes of electric capacity.The method has been avoided complicated silicon dioxide sacrificial layer to empty technology and release aperture has been sealed the technology that forms vacuum chamber, has improved the technology manufacturability greatly.In addition, also can be provided with the stop block that prevents the pressure sensitive film excessive deformation at the bonding face of silicon chip, the design limit through stop block the maximum displacement of pressure-sensitive film, preserve the function with overload protection to realize the sensor normal pressure.But the method but has bigger stray capacitance, greatly reduces the performance of device, and in addition, the method manufacturing cost is also relatively more expensive, does not also become the main flow method for making of industry member at present.
In sum, carry out that technology is simple, volume is little, the high and low power consumption of precision and the research of capacitance pressure transducer, and preparation method thereof cheaply has positive impetus to the progress of whole pressure transducer technical field and the development of related industry.
The utility model content
The fundamental purpose of the utility model is to provide a kind of low cost, the simple capacitance pressure transducer, of technology.
For solving the problems of the technologies described above; The utility model adopts following technical scheme: a kind of capacitance pressure transducer; It comprises substrate, cover bottom crown on the substrate, pressure sensitive film, the capacitance gap bottom crown and pressure sensitive film between relative with bottom crown and to be surrounded on capacitance gap peripheral and in order to support the anchor point of said pressure sensitive film; Said pressure sensitive film and said bottom crown are respectively as two electrodes of said capacitance pressure transducer; Said capacitance pressure transducer, also comprises first pressure welding point and second pressure welding point that is deposited on respectively on said bottom crown and the said pressure sensitive film; Said pressure sensitive film is provided with the gas port that capacitance gap and ambient atmos are interconnected, and said gas port is by metallic seal and then finally make said capacitance gap become the enclosed vacuum cavity.
As the further improved technical scheme of the utility model, said pressure sensitive film comprises first polysilicon layer and covers second polysilicon layer on said first polysilicon layer.
As the further improved technical scheme of the utility model, said second polysilicon layer and said bottom crown are respectively as said two electrodes of said capacitance pressure transducer.
As the further improved technical scheme of the utility model, said second pressure welding point is deposited on said second polysilicon layer.
As the further improved technical scheme of the utility model, said first pressure welding point is deposited on the said bottom crown.
As the further improved technical scheme of the utility model, said gas port runs through said first polysilicon layer and said second polysilicon layer.
As the further improved technical scheme of the utility model, said metal runs through said first polysilicon layer and said second polysilicon layer.
Compared with prior art; The utility model adopts the surface silicon fine process to make capacitance pressure transducer; Solved in the SOI technology long and technology problem rambunctious release time; Also solved simultaneously the bigger problem of device stray capacitance that SOI technology forms, and manufacturing process is simple, cost is low, manufacturability is strong, is fit to large-scale production.
Description of drawings
Figure 1A to Fig. 1 G is the manufacturing process synoptic diagram of the utility model capacitance pressure transducer;
Fig. 2 is the schematic perspective view of the utility model capacitance pressure transducer;
Fig. 3 is the vertical view of the utility model capacitance pressure transducer;
Fig. 4 is the sectional axonometric drawing of the utility model capacitance pressure transducer, along the C-A-B line.
Embodiment
With reference to the accompanying drawing of the utility model, more detailed description goes out the embodiment of the utility model below.
The utility model has disclosed a kind of capacitance pressure transducer, 20 and manufacturing approach thereof, please join shown in Figure 1A to 1G, and wherein the manufacturing approach of the utility model capacitance pressure transducer, comprises the steps:
A) please join shown in Figure 1A, at first on substrate 21a, carry out heavy doping, obtain the bottom crown 21b of the high heavily doped layer of electric conductivity as the utility model capacitance pressure transducer, 100, subsequently on said bottom crown 21b silicon oxide deposition to form sacrifice layer 22.Deposition process includes but not limited to that low-pressure chemical vapor phase deposition (LPCVD) and plasma strengthen vapor deposition (PECVD).Said substrate 21a is a silicon substrate.
B) please join shown in Figure 1B, the deposit first polysilicon layer 23a on said sacrifice layer 22, and to this first polysilicon layer 23a mix with photoetching to form sacrifice layer release aperture 27b, wherein deposition process includes but not limited to low-pressure chemical vapor phase deposition (LPCVD).
C) please join shown in Fig. 1 C,, said sacrifice layer 22 emptied from sacrifice layer release aperture 27b, to form capacitance gap 25 through hydrofluorite wet etching or hydrogen fluoride gas very high frequency(VHF) etching.
D) please join shown in Fig. 1 D, the deposit second polysilicon layer 23b seals up sacrifice layer release aperture 27b, thereby said capacitance gap 25 is become closed cavity, subsequently this second polysilicon layer 23b is mixed, and doping method includes but not limited to that diffusion or ion inject.Said first polysilicon layer 23a and the said second polysilicon layer 23b decomposition pressure sensitive membrane.The said second polysilicon layer 23b is as the top crown of the utility model capacitance pressure transducer, 100.
E) please join shown in Fig. 1 E, above-mentioned pressure sensitive film is carried out photoetching and etching, form the gas port 27a that is communicated with capacitance gap 25, the part first polysilicon layer 23a and the part second polysilicon layer 23b that will be positioned at bottom crown 21b top simultaneously etch away.
F) please join shown in Fig. 1 F,, utilize polysilicon, sacrifice layer 22 parts are got rid of exposing bottom crown 21b, and not have removed sacrifice layer 22 to form anchor points 26 as mask through hydrofluorite wet etching or hydrogen fluoride gas very high frequency(VHF) etching.Said anchor point 26 is fixed on the substrate 21a through bottom crown 21b, in order to the abutment pressure sensitive membrane.
G) please join shown in Fig. 1 G, last, through physical vapor deposition (PVD) metal is deposited on respectively on the bottom crown 21b and the second polysilicon layer 23b, and carries out photoetching and etching, finally form first pressure welding point 241 and second pressure welding point 242.Simultaneously, said gas port 27a is sealed by metal 24a, and then said capacitance gap 25 is become the enclosed vacuum cavity.In this embodiment, because capacitance gap 25 is the enclosed vacuum cavity, so said capacitance pressure transducer, 20 is a Capacitive Absolute Pressure Sensor.
Through adopting the surface silicon fine process; The manufacturing approach of the utility model capacitance pressure transducer, has solved in the SOI technology long and technology problem rambunctious release time; Also solved simultaneously the bigger problem of device stray capacitance that SOI technology forms; And manufacturing process is simple, cost is low, manufacturability is strong, is fit to large-scale production.
Please join Fig. 2 to shown in Figure 4; See that from structure the utility model capacitance pressure transducer, 20 comprises substrate 21a, cover bottom crown 21b on the substrate 21a, first polysilicon layer 23a, the capacitance gap 25 bottom crown 21b and first polysilicon layer 23a between relative with bottom crown 21b, be fixed on the substrate 21a and in order to the anchor point 26 that supports the first polysilicon layer 23a and cover the second polysilicon layer 23b on the first polysilicon layer 23a.The said first polysilicon layer 23a and the second polysilicon layer 23b form the pressure sensitive film of the utility model capacitance pressure transducer, 20.Said anchor point 26 is between the bottom crown 21b and the first polysilicon layer 23a, and said anchor point 26 is fixed on the substrate 21a through bottom crown 21b, with the abutment pressure sensitive membrane.Said anchor point 26 surrounds capacitance gap 25 from the side.Said second polysilicon layer 23b and bottom crown 21b are respectively as two electrodes of the utility model capacitance pressure transducer, 20; In order to derive this two electrodes, said capacitance pressure transducer, 20 also comprises first pressure welding point 241 and second pressure welding point 242 that is deposited on respectively on the bottom crown 21b and the second polysilicon layer 23b.Said pressure sensitive film is provided with the gas port 27a that is interconnected with capacitance gap 25, and said gas port 27a is sealed by metal 24a, and then finally makes said capacitance gap 25 become the enclosed vacuum cavity.Said second pressure welding point 242 is higher than said first pressure welding point 241.Said metal runs through said first polysilicon layer 23a and the said second polysilicon layer 23b.
The utility model capacitance pressure transducer, 20 can not produce bigger stray capacitance, and technology is simple, cost is low, manufacturability is strong, is fit to large-scale production.
Although disclose the specific embodiment and the accompanying drawing of the utility model for the purpose of illustration; Its purpose is to help to understand the content of the utility model and implement according to this; But it will be appreciated by those skilled in the art that: in the spirit and scope that do not break away from the utility model and appended claim, various replacements, variation and modification all are possible.Therefore, the utility model should not be limited to most preferred embodiment and the disclosed content of accompanying drawing, and the utility model requires the scope of protection to be as the criterion with the scope that claims define.
Claims (7)
1. capacitance pressure transducer; It comprises substrate, cover bottom crown on the substrate, pressure sensitive film, the capacitance gap bottom crown and pressure sensitive film between relative with bottom crown and to be surrounded on capacitance gap peripheral and in order to support the anchor point of said pressure sensitive film; Said pressure sensitive film and said bottom crown are respectively as two electrodes of said capacitance pressure transducer; It is characterized in that; Said capacitance pressure transducer, also comprises first pressure welding point and second pressure welding point that is deposited on respectively on said bottom crown and the said pressure sensitive film; Said pressure sensitive film is provided with the gas port that capacitance gap and ambient atmos are interconnected, and said gas port is by metallic seal and then finally make said capacitance gap become the enclosed vacuum cavity.
2. capacitance pressure transducer, as claimed in claim 1 is characterized in that: said pressure sensitive film comprises first polysilicon layer and covers second polysilicon layer on said first polysilicon layer.
3. capacitance pressure transducer, as claimed in claim 2 is characterized in that: said second polysilicon layer and said bottom crown are respectively as said two electrodes of said capacitance pressure transducer.
4. capacitance pressure transducer, as claimed in claim 2 is characterized in that: said second pressure welding point is deposited on said second polysilicon layer.
5. capacitance pressure transducer, as claimed in claim 4 is characterized in that: said first pressure welding point is deposited on the said bottom crown.
6. capacitance pressure transducer, as claimed in claim 2 is characterized in that: said gas port runs through said first polysilicon layer and said second polysilicon layer.
7. capacitance pressure transducer, as claimed in claim 2 is characterized in that: said metal runs through said first polysilicon layer and said second polysilicon layer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012200559661U CN202420729U (en) | 2012-02-21 | 2012-02-21 | Capacitive pressure sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012200559661U CN202420729U (en) | 2012-02-21 | 2012-02-21 | Capacitive pressure sensor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN202420729U true CN202420729U (en) | 2012-09-05 |
Family
ID=46745484
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2012200559661U Withdrawn - After Issue CN202420729U (en) | 2012-02-21 | 2012-02-21 | Capacitive pressure sensor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN202420729U (en) |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103411632A (en) * | 2013-07-03 | 2013-11-27 | 马瑞利汽车电子(广州)有限公司 | Door handle sensor |
| CN104807567A (en) * | 2014-01-24 | 2015-07-29 | 英飞凌技术德累斯顿有限责任公司 | Sensor structures, systems and methods with improved integration and optimized footprint |
| US9546923B2 (en) | 2014-01-24 | 2017-01-17 | Infineon Technologies Dresden Gmbh | Sensor structures, systems and methods with improved integration and optimized footprint |
| US9783411B1 (en) | 2016-11-11 | 2017-10-10 | Rosemount Aerospace Inc. | All silicon capacitive pressure sensor |
| CN107360526A (en) * | 2016-05-09 | 2017-11-17 | 上海微联传感科技有限公司 | Silicon microphone and its manufacture method |
| CN107957273A (en) * | 2018-01-16 | 2018-04-24 | 北京先通康桥医药科技有限公司 | With the sensor pressed with ultrasound functions |
| CN114323408A (en) * | 2021-11-15 | 2022-04-12 | 歌尔微电子股份有限公司 | Multi-range multi-sensitivity pressure MEMS chip |
| CN114623955A (en) * | 2021-10-18 | 2022-06-14 | 胡耿 | Micro-polar distance capacitance type force-sensitive sensor and manufacturing method thereof |
| CN115479582A (en) * | 2022-11-03 | 2022-12-16 | 湖南大学 | A barometer for navigation |
-
2012
- 2012-02-21 CN CN2012200559661U patent/CN202420729U/en not_active Withdrawn - After Issue
Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103411632B (en) * | 2013-07-03 | 2016-04-20 | 马瑞利汽车电子(广州)有限公司 | A kind of door handle sensor |
| CN103411632A (en) * | 2013-07-03 | 2013-11-27 | 马瑞利汽车电子(广州)有限公司 | Door handle sensor |
| CN104807567B (en) * | 2014-01-24 | 2018-02-13 | 英飞凌技术德累斯顿有限责任公司 | Sensor construction, system and method with improved integrated and optimization encapsulation |
| US9546923B2 (en) | 2014-01-24 | 2017-01-17 | Infineon Technologies Dresden Gmbh | Sensor structures, systems and methods with improved integration and optimized footprint |
| CN104807567A (en) * | 2014-01-24 | 2015-07-29 | 英飞凌技术德累斯顿有限责任公司 | Sensor structures, systems and methods with improved integration and optimized footprint |
| US10060816B2 (en) | 2014-01-24 | 2018-08-28 | Infineon Technologies Ag | Sensor structures, systems and methods with improved integration and optimized footprint |
| CN107360526A (en) * | 2016-05-09 | 2017-11-17 | 上海微联传感科技有限公司 | Silicon microphone and its manufacture method |
| US9783411B1 (en) | 2016-11-11 | 2017-10-10 | Rosemount Aerospace Inc. | All silicon capacitive pressure sensor |
| CN107957273A (en) * | 2018-01-16 | 2018-04-24 | 北京先通康桥医药科技有限公司 | With the sensor pressed with ultrasound functions |
| CN107957273B (en) * | 2018-01-16 | 2024-05-03 | 北京先通康桥医药科技有限公司 | Sensor with touch-press and ultrasonic functions |
| CN114623955A (en) * | 2021-10-18 | 2022-06-14 | 胡耿 | Micro-polar distance capacitance type force-sensitive sensor and manufacturing method thereof |
| CN114323408A (en) * | 2021-11-15 | 2022-04-12 | 歌尔微电子股份有限公司 | Multi-range multi-sensitivity pressure MEMS chip |
| CN115479582A (en) * | 2022-11-03 | 2022-12-16 | 湖南大学 | A barometer for navigation |
| CN115479582B (en) * | 2022-11-03 | 2023-02-14 | 湖南大学 | A barometer for navigation |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN202420729U (en) | Capacitive pressure sensor | |
| CN103257005B (en) | Capacitance pressure transducer, and manufacture method thereof | |
| KR101965089B1 (en) | Integrated structure of mems microphone and pressure sensor, and manufacturing method thereof | |
| CN108254106B (en) | Preparation method of silicon-glass-silicon four-layer structure resonant MEMS pressure sensor | |
| CN103281659B (en) | MEMS microphone and preparation method thereof | |
| CN101692016B (en) | Atmospheric pressure sensor compatible with CMOS process and preparation process thereof | |
| CN102778586B (en) | Differential capacitive micro-acceleration transducer and manufacturing method thereof | |
| CN206341427U (en) | Mems microphone | |
| US9221675B2 (en) | Chip with integrated circuit and micro-silicon condenser microphone integrated on single substrate and method for making the same | |
| CN103379392B (en) | Condenser type sonac chip and preparation method thereof | |
| DE60143202D1 (en) | MICROMECHANIC MANUFACTURED ABSOLUTE PRESSURE SENSOR | |
| CN103991836B (en) | The manufacture method of MEMS sensor | |
| CN103011057A (en) | Preparation method of capacitive barometric sensor of micro-electronic-mechanical system | |
| CN103983395B (en) | A kind of micropressure sensor and preparation thereof and detection method | |
| CN102967409A (en) | Wireless inactive capacitive gas pressure sensor | |
| CN203279172U (en) | MEMS (Micro-Electro-Mechanical System) microphone | |
| CN202906852U (en) | An impact-resistant quartz crystal resonator | |
| CN106568548A (en) | Capacitance-type absolute-pressure micro-pressure gas pressure sensor based on SOI-MEMS (Silicon on Insulator-Micro-Electro-Mechanical System) technology | |
| CN104422549A (en) | Capacitive pressure sensor and forming method thereof | |
| TW201719130A (en) | Micro feedback-chamber sensor and method of manufacturing such sensor | |
| CN103347241B (en) | capacitor type silicon microphone chip and preparation method thereof | |
| CN101355828B (en) | Monolithic integration method for integrated circuit based on SOI silicon chip and capacitance type micro-silicon microphone, and chip | |
| CN202150936U (en) | MEMS sensor | |
| CN104280186B (en) | The preparation of temperature drift self compensation SOI pressure transducer and compensation method | |
| CN105084296B (en) | Manufacturing method for MEMS(Micro Electro Mechanical Systems) capacitive pressure transducer |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned |
Granted publication date: 20120905 Effective date of abandoning: 20150909 |
|
| RGAV | Abandon patent right to avoid regrant |