CN1278120C - Capacitance type relative moisture sensor - Google Patents
Capacitance type relative moisture sensor Download PDFInfo
- Publication number
- CN1278120C CN1278120C CN 200510037809 CN200510037809A CN1278120C CN 1278120 C CN1278120 C CN 1278120C CN 200510037809 CN200510037809 CN 200510037809 CN 200510037809 A CN200510037809 A CN 200510037809A CN 1278120 C CN1278120 C CN 1278120C
- Authority
- CN
- China
- Prior art keywords
- electric capacity
- pole plate
- crown
- capacitance pole
- top crown
- 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.)
- Expired - Fee Related
Links
Images
Landscapes
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
Abstract
The present invention discloses a capacitance type relative humidity sensor used for a microelectronic mechanical system. The present invention is composed of a substrate, a lower capacitance pole plate and an upper capacitance pole plate, wherein the lower capacitance pole plate is arranged on the substrate; the upper capacitance pole plate is arranged above the lower capacitance pole plate; an oxide layer is arranged on a region outside an upper capacitance pole plate projection region of the upper capacitance pole plate; an upper capacitance pole plate leading wire and a lower capacitance pole plate leading wire are arranged on the oxide layer; a moisture sensing dielectric layer is arranged on the upper capacitance pole plate. The present invention is characterized in that the upper capacitance pole plate is used for support via connecting rods and four square anchor regions fixed on the oxide layer; the present invention has the advantages of providing a deformation space for a movable upper pole plate, etc.
Description
Technical field
The present invention relates to a kind of relative humidity sensor, especially a kind of Relative Humidity Sensor of microelectromechanical systems.
Background technology
Moisture measurement all has important use in departments such as industrial and agricultural production, meteorology, environmental protection, national defence, scientific research, aviations.Humidity sensor has developed a lot of years as ingredient important in the humidity measurement system.Develop into the LiCl electrolyte humidity sensor that to export electric signal by initial hair meter and psychrometer.The electrolyte humidity sensor has appearred in the evolution, Ceramic Humidity Sensor, semi-conductor junction type and MOS type humidity sensor and emerging high molecule humidity sensor.It is little to have a volume based on the miniature humidity sensor of MEMS technology, and price is low, and the characteristics of good product consistency are the focuses of humidity sensor research in recent years.1997, Buchhold has proposed to utilize the MEMS technology to make the pressure resistance type humidity sensor, this humidity sensor is a movable sensitive film, cover one deck absorbent polymer on the film, when extraneous humidity changes, polymkeric substance generation breathing, thus drive movable film generation deformation, finally cause the change in resistance of film four limit voltage dependent resistor (VDR)s.The intrinsic bigger temperature drift characteristic of resistance makes it in the very big application of temperature variation limitation be arranged.Chatzandroulis utilized silicon micro-machining technology to make the humidity sensor of cantilever beam structure in 2002, covered hygroscopic material on the semi-girder, after having absorbed ambient humidity, hygroscopic material expands generation stress, and weight increases, make the semi-girder bending, thereby make the electric capacity between semi-girder and substrate change.This sensor is that condenser type so temperature drift are less, but because it deposits at one end fixing cantilever beam structure, and reliability is poor, and semi-girder in dispose procedure because warpage in various degree can take place in the effect of unrelieved stress, homogeneity of product is poor.
Summary of the invention
The invention provides a kind of temperature that is used for microelectromechanical systems and float little Relative Humidity Sensor, the present invention has the advantage of highly sensitive and good reliability simultaneously.
The present invention adopts following technical scheme:
A kind of Relative Humidity Sensor that is used for microelectromechanical systems, form by substrate, electric capacity bottom crown and electric capacity top crown, the electric capacity bottom crown is located on the substrate, the electric capacity top crown is positioned at the top of electric capacity bottom crown, zone beyond the electric capacity top crown projection of electric capacity top crown is provided with oxide layer, oxide layer is provided with the upper and lower pole plate lead-in wire of electric capacity, on the electric capacity top crown, be provided with the humidity-sensitive medium layer, it is characterized in that the electric capacity top crown is fixed on four square anchor districts on the oxide layer by it and adds connecting rod and support.
Compared with prior art, the present invention has following advantage:
The present invention is the movable thin-film capacitor formula humidity sensor that is used for perception ambient humidity signal, is made up of the lead-in wire of bottom crown on the electric capacity and connection electrode plate.The electric capacity top crown is a movable film, and bottom crown is a fixed electorde, covers one deck hygroscopic material on the top crown, when ambient humidity changes, causes that hygroscopic material expands or contraction, produces deformation thereby drive the electric capacity top crown, thereby causes the variation of capacitance.Below the electric capacity top crown, be provided with cavity, for movable top crown provides the deformation space.
The present invention can adopt standard CMOS process to combine with the MEMS process technology and make, the precision height, and long-term reliability is good.The cavity of top crown below forms by bonding techniques among the present invention, and generally adopt first deposit LTO (low temperature silicon dioxide) or PSG (silicon dioxide of phosphorus doping) in the traditional handicraft as sacrifice layer, releasing sacrificial layer forms cavity then, this tends to cause structure and the cavity bottom adhesion that is released for the bigger cavity of area, make component failure, the present invention adopts bonding techniques will overcome this defective, has strengthened the reliability of sensor greatly.Top crown is the movable film of Corner Strapped, and whole top crown supports by four fixed angles, compares with the film that four limits are fixing, its sensitivity greatly improves, and movable film four limits are unsettled, do not contact with oxide layer, can effectively reduce the edge stray capacitance like this.This sensor front end adopts standard CMOS process, and the body process technology is adopted in the rear end, and does not influence the IC processes of front end.Guarantee the compatibility of IC technology, helped the batch process of sensor.Rear end element is processed with and is beneficial to reliability and the intensity that strengthens movable film, increases movable film size and can effectively improve humidity sensitive changes in capacitance amount.The capacitance type humidity sensor based on the manufacturing of MEMS technology that the present invention proposes has effectively improved sensitivity and reliability, and temperature is floated little, is applicable to the high-acruracy survey of envionmental humidity.
Description of drawings
Fig. 1 is a structural representation of the present invention.
Fig. 2 is a vertical view of the present invention.
Fig. 3 is a sectional view of the present invention.
Embodiment
A kind of Relative Humidity Sensor that is used for microelectromechanical systems, by substrate 1, electric capacity bottom crown 2 and electric capacity top crown 5 are formed, electric capacity bottom crown 2 is located on the substrate 1, electric capacity top crown 5 is positioned at the top of electric capacity bottom crown 2, zone beyond electric capacity top crown 5 projections of electric capacity top crown 5 is provided with oxide layer 3, oxide layer 3 is provided with on the electric capacity, bottom crown lead-in wire 41,42, on electric capacity top crown 5, be provided with the humidity-sensitive medium layer, electric capacity top crown 5 is fixed on four square anchor districts on the oxide layer 3 by connecting rod, in the present embodiment, electric capacity top crown 5 is fixed on the oxide layer 3 by four angles, and the humidity-sensitive medium layer is a polyimide layer.Substrate 1 is a body silicon in the present embodiment, and electric capacity bottom crown 2 is the phosphorus heavily doped region, and oxide layer 3 is a silicon dioxide, and electric capacity top crown 5 is the boron heavily doped region, and bottom crown lead-in wire 41 and 42 is an aluminium on the electric capacity.The present invention can make of following technology: prepare two silicon chip 1# and 2#.To silicon chip 1#, on substrate 1, carry out phosphonium ion and inject, form electric capacity bottom crown 2; CVD method deposit silicon dioxide layer 3 carries out photoetching to oxide layer 3, forms cavity and electric capacity bottom crown lead hole that the top crown motion is held in power supply.Silicon chip 2# is carried out the boron ion inject, form a conductive layer; The face and the silicon chip 2# boron ion injection face that silicon chip 1# are had etch pattern carry out bonding; Then silicon chip 2# is carried out attenuate by chemically mechanical polishing and wet etching, only remaining at last boron ion implanted layer; Form electric capacity top crown 5 by dry etching, evaporation of aluminum and photoetching form bottom crown lead-in wire 41 and 42 on the electric capacity, utilize whirl coating to be coated with one deck polyimide, and photoetching formation humidity-sensitive medium layer 6, at last polyimide are carried out imidization.Humidity-sensitive medium layer 6 of the present invention is because the variation of external environment relative humidity, the airborne aqueous vapor molecule of absorption/desorption, make the volume of humidity-sensitive medium layer 6 expand or shrink, drive electric capacity top crown 5 deformation takes place, capacitance between electric capacity top crown 5 and the electric capacity bottom crown 2 changes, and envionmental humidity increases, humidity-sensitive medium layer 6 absorption aqueous vapor molecule, volumetric expansion drives the electric capacity top crown and is bent downwardly, and the capacitance between electric capacity top crown 5 and the electric capacity bottom crown 2 increases.
Claims (2)
1, a kind of Relative Humidity Sensor that is used for microelectromechanical systems, by substrate (1), electric capacity bottom crown (2) and electric capacity top crown (5) are formed, electric capacity bottom crown (2) is located on the substrate (1), electric capacity top crown (5) is positioned at the top of electric capacity bottom crown (2), zone beyond electric capacity top crown (5) projection of electric capacity top crown (5) is provided with oxide layer (3), oxide layer (3) is provided with on the electric capacity, bottom crown lead-in wire (41,42), on electric capacity top crown (5), be provided with the humidity-sensitive medium layer, it is characterized in that being provided with in the below of electric capacity top crown (5) cavity that forms by bonding techniques, electric capacity top crown (5) is fixed on four square anchor districts on the oxide layer (3) by it and adds connecting rod and support.
2, Relative Humidity Sensor according to claim 1 is characterized in that the humidity-sensitive medium layer is a polyimide layer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200510037809 CN1278120C (en) | 2005-02-23 | 2005-02-23 | Capacitance type relative moisture sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200510037809 CN1278120C (en) | 2005-02-23 | 2005-02-23 | Capacitance type relative moisture sensor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1651910A CN1651910A (en) | 2005-08-10 |
| CN1278120C true CN1278120C (en) | 2006-10-04 |
Family
ID=34876189
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 200510037809 Expired - Fee Related CN1278120C (en) | 2005-02-23 | 2005-02-23 | Capacitance type relative moisture sensor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1278120C (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7683636B2 (en) * | 2007-10-26 | 2010-03-23 | Honeywell International Inc. | Structure for capacitive balancing of integrated relative humidity sensor |
| WO2016134079A1 (en) | 2015-02-17 | 2016-08-25 | Honeywell International Inc. | Humidity sensor and method for manufacturing the sensor |
| EP3244201B1 (en) | 2016-05-13 | 2021-10-27 | Honeywell International Inc. | Fet based humidity sensor with barrier layer protecting gate dielectric |
| CN112461887B (en) * | 2021-01-25 | 2021-04-20 | 南京高华科技股份有限公司 | Humidity sensor based on MEMS structure |
-
2005
- 2005-02-23 CN CN 200510037809 patent/CN1278120C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CN1651910A (en) | 2005-08-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101620197B (en) | Rapid response CMOS relative humidity sensor | |
| CN1203312C (en) | Capacitance type relative humidity sensor | |
| CN103134837B (en) | There is the adjustable humidity sensor of integrated heater | |
| CN101308110B (en) | Low-power consumption double module integrated humidity sensitive chip with heating function and its manufacture method | |
| CN102439430B (en) | Humidity sensor of capacitance type and method of fabricating same | |
| CN1278120C (en) | Capacitance type relative moisture sensor | |
| CN103213942B (en) | A kind of preparation method of passive and wireless electric capacity formula humidity sensor | |
| CN103438936B (en) | Based on the condenser type temperature of SOI sheet device layer silicon anode linkage, humidity and baroceptor integrated manufacturing method | |
| CN103487474A (en) | MEMS (micro-electromechanical systems) capacitive humidity sensor with high sensitivity and fast response | |
| CN102565149A (en) | Capacitance humidity sensor with temperature drift compensation and making method thereof | |
| CN103675042B (en) | CMOS MEMS capacitive humidity sensor | |
| CN107290241B (en) | QCM humidity sensor and preparation method thereof | |
| CN105067682A (en) | Flexible capacitive humidity sensor and preparation method thereof | |
| CN104634833A (en) | MEMS capacitance-type relative humidity sensor and preparation method thereof | |
| CN201522471U (en) | Capacitance type relative humidity sensor | |
| CN102243199A (en) | Relative humidity sensor of fast-response microelectronic mechanical system | |
| CN1217157C (en) | Integrated temperature, humidity and atmospheric pressure sensor chip | |
| CN106768050B (en) | Single-chip high-precision temperature and humidity sensor | |
| CN102262107A (en) | Capacitive relative humidity sensor for micro-electromechanical system | |
| CN106680333A (en) | Humidity sensitive capacitor and manufacturing method thereof | |
| CN102565142B (en) | Low-temperature drift piezoresistive humidity sensor and manufacturing method thereof | |
| CN206557144U (en) | A kind of humicap | |
| CN1210565C (en) | Miniature humidity sensor | |
| CN103645219B (en) | Multrirange CMOS MEMS capacitive humidity sensor | |
| CN209894749U (en) | Double-capacitor temperature and humidity sensor |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20061004 Termination date: 20170223 |