CN113483926B - Explosion field MEMS piezoresistive pressure sensor - Google Patents
Explosion field MEMS piezoresistive pressure sensorDownload PDFInfo
- Publication number
- CN113483926B CN113483926BCN202110798999.9ACN202110798999ACN113483926BCN 113483926 BCN113483926 BCN 113483926BCN 202110798999 ACN202110798999 ACN 202110798999ACN 113483926 BCN113483926 BCN 113483926B
- Authority
- CN
- China
- Prior art keywords
- silicon
- cavity
- piezoresistors
- film
- strain film
- 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.)
- Active
Links
- 238000004880explosionMethods0.000titleclaimsabstractdescription18
- XUIMIQQOPSSXEZ-UHFFFAOYSA-NSiliconChemical compound[Si]XUIMIQQOPSSXEZ-UHFFFAOYSA-N0.000claimsabstractdescription179
- 229910052710siliconInorganic materials0.000claimsabstractdescription179
- 239000010703siliconSubstances0.000claimsabstractdescription179
- 239000000758substrateSubstances0.000claimsabstractdescription35
- 239000011521glassSubstances0.000claimsabstractdescription34
- 230000035939shockEffects0.000claimsabstractdescription26
- 239000012528membraneSubstances0.000claimsabstractdescription12
- 239000002184metalSubstances0.000claimsdescription23
- 229910052751metalInorganic materials0.000claimsdescription23
- 238000005530etchingMethods0.000claimsdescription20
- 238000000034methodMethods0.000claimsdescription11
- 238000001259photo etchingMethods0.000claimsdescription9
- 238000004518low pressure chemical vapour depositionMethods0.000claimsdescription5
- 230000004323axial lengthEffects0.000claimsdescription4
- 230000000694effectsEffects0.000claimsdescription3
- 239000012212insulatorSubstances0.000claimsdescription3
- 238000004519manufacturing processMethods0.000claimsdescription3
- 238000005474detonationMethods0.000claims3
- 238000000206photolithographyMethods0.000claims1
- 230000035945sensitivityEffects0.000abstractdescription5
- 238000005259measurementMethods0.000abstractdescription4
- 235000012431wafersNutrition0.000description25
- VYPSYNLAJGMNEJ-UHFFFAOYSA-NSilicium dioxideChemical compoundO=[Si]=OVYPSYNLAJGMNEJ-UHFFFAOYSA-N0.000description10
- 238000010586diagramMethods0.000description5
- 239000000377silicon dioxideSubstances0.000description5
- 235000012239silicon dioxideNutrition0.000description5
- 239000002210silicon-based materialSubstances0.000description4
- 229910052581Si3N4Inorganic materials0.000description3
- 239000013078crystalSubstances0.000description3
- HQVNEWCFYHHQES-UHFFFAOYSA-Nsilicon nitrideChemical compoundN12[Si]34N5[Si]62N3[Si]51N64HQVNEWCFYHHQES-UHFFFAOYSA-N0.000description3
- 229910052796boronInorganic materials0.000description2
- 238000000708deep reactive-ion etchingMethods0.000description2
- 238000013461designMethods0.000description2
- 239000002360explosiveSubstances0.000description2
- 239000010931goldSubstances0.000description2
- 229920002120photoresistant polymerPolymers0.000description2
- 238000001020plasma etchingMethods0.000description2
- BASFCYQUMIYNBI-UHFFFAOYSA-NplatinumSubstances[Pt]BASFCYQUMIYNBI-UHFFFAOYSA-N0.000description2
- 238000005498polishingMethods0.000description2
- 238000002360preparation methodMethods0.000description2
- 238000012360testing methodMethods0.000description2
- 239000010936titaniumSubstances0.000description2
- RTAQQCXQSZGOHL-UHFFFAOYSA-NTitaniumChemical compound[Ti]RTAQQCXQSZGOHL-UHFFFAOYSA-N0.000description1
- 238000000137annealingMethods0.000description1
- 238000004140cleaningMethods0.000description1
- 238000000151depositionMethods0.000description1
- 238000009826distributionMethods0.000description1
- 229910052737goldInorganic materials0.000description1
- 239000012535impuritySubstances0.000description1
- 230000003647oxidationEffects0.000description1
- 238000007254oxidation reactionMethods0.000description1
- 229910052697platinumInorganic materials0.000description1
- 238000012545processingMethods0.000description1
- 238000004088simulationMethods0.000description1
- 239000007787solidSubstances0.000description1
- 238000004528spin coatingMethods0.000description1
- 238000004544sputter depositionMethods0.000description1
- 229910052719titaniumInorganic materials0.000description1
Images
Classifications
- 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
- G01L1/20—Measuring force or stress, in general by measuring variations in ohmic resistance of solid materials or of electrically-conductive fluids; by making use of electrokinetic cells, i.e. liquid-containing cells wherein an electrical potential is produced or varied upon the application of stress
- G01L1/22—Measuring force or stress, in general by measuring variations in ohmic resistance of solid materials or of electrically-conductive fluids; by making use of electrokinetic cells, i.e. liquid-containing cells wherein an electrical potential is produced or varied upon the application of stress using resistance strain gauges
- G01L1/225—Measuring circuits therefor
- G01L1/2262—Measuring circuits therefor involving simple electrical bridges
- 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
- G01L1/20—Measuring force or stress, in general by measuring variations in ohmic resistance of solid materials or of electrically-conductive fluids; by making use of electrokinetic cells, i.e. liquid-containing cells wherein an electrical potential is produced or varied upon the application of stress
- G01L1/22—Measuring force or stress, in general by measuring variations in ohmic resistance of solid materials or of electrically-conductive fluids; by making use of electrokinetic cells, i.e. liquid-containing cells wherein an electrical potential is produced or varied upon the application of stress using resistance strain gauges
- G01L1/2287—Measuring force or stress, in general by measuring variations in ohmic resistance of solid materials or of electrically-conductive fluids; by making use of electrokinetic cells, i.e. liquid-containing cells wherein an electrical potential is produced or varied upon the application of stress using resistance strain gauges constructional details of the strain gauges
- G01L1/2293—Measuring force or stress, in general by measuring variations in ohmic resistance of solid materials or of electrically-conductive fluids; by making use of electrokinetic cells, i.e. liquid-containing cells wherein an electrical potential is produced or varied upon the application of stress using resistance strain gauges constructional details of the strain gauges of the semi-conductor type
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L19/00—Details of, or accessories for, apparatus for measuring steady or quasi-steady pressure of a fluent medium insofar as such details or accessories are not special to particular types of pressure gauges
- G01L19/06—Means for preventing overload or deleterious influence of the measured medium on the measuring device or vice versa
- G01L19/0618—Overload protection
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L9/00—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means
- G01L9/0041—Transmitting or indicating the displacement of flexible diaphragms
- G01L9/0051—Transmitting or indicating the displacement of flexible diaphragms using variations in ohmic resistance
- G01L9/0052—Transmitting or indicating the displacement of flexible diaphragms using variations in ohmic resistance of piezoresistive elements
- G01L9/0054—Transmitting or indicating the displacement of flexible diaphragms using variations in ohmic resistance of piezoresistive elements integral with a semiconducting diaphragm
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L9/00—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means
- G01L9/02—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means by making use of variations in ohmic resistance, e.g. of potentiometers, electric circuits therefor, e.g. bridges, amplifiers or signal conditioning
- G01L9/04—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means by making use of variations in ohmic resistance, e.g. of potentiometers, electric circuits therefor, e.g. bridges, amplifiers or signal conditioning of resistance-strain gauges
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L9/00—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means
- G01L9/0041—Transmitting or indicating the displacement of flexible diaphragms
- G01L9/0051—Transmitting or indicating the displacement of flexible diaphragms using variations in ohmic resistance
- G01L2009/0066—Mounting arrangements of diaphragm transducers; Details thereof, e.g. electromagnetic shielding means
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Measuring Fluid Pressure (AREA)
- Pressure Sensors (AREA)
Abstract
Description
Technical Field
The invention relates to the technical field of MEMS piezoresistive pressure sensors, in particular to an explosion field MEMS piezoresistive pressure sensor.
Background
When the explosive explodes in a closed environment, the explosive generates two effects of pressure, namely shock wave pressure and quasi-static pressure. Wherein: the shock wave pressure signal belongs to a typical non-stationary random signal and is characterized by large peak value, quick abrupt change and short duration; the quasi-static pressure is mainly the pressure generated by the thermal motion of gas after the temperature is increased due to the heat released by explosion, and has low peak value and long acting time.
Because the piezoelectric pressure sensor has better dynamic characteristics and overload capacity, the piezoelectric pressure sensor is commonly used for testing the overpressure peak value of the shock wave at present, but the low-frequency characteristic, particularly the zero-frequency characteristic, is poor, and is not suitable for measuring the quasi-static pressure.
The piezoresistive pressure sensor has good dynamic characteristics and low-frequency characteristics, but the overload capacity of the piezoresistive pressure sensor is generally 2-3 times of the range, is far less than that of the piezoelectric pressure sensor with 10 times of the range, and the full-range output signal is only 100 mV. If the measurement of the overpressure peak value of the shock wave pressure is required to be met, the sensor is ensured not to be damaged, the sensitivity of the piezoresistive pressure sensor is required to be sacrificed to meet the requirement of the measuring range, the quasi-static pressure is generally one tenth of the overpressure peak value of the shock wave, and at the moment, if the measurement of the quasi-static pressure is aligned, a great test error is generated, so that the shock wave pressure and the quasi-static pressure cannot be tested at the same time.
Disclosure of Invention
In view of the shortcomings or drawbacks of the prior art, it is an object of the present invention to provide an explosion field MEMS piezoresistive pressure sensor.
In order to achieve the above object, the present invention provides an explosion field MEMS piezoresistive pressure sensor comprising:
the first piezoresistive pressure sensor comprises a first silicon strain film, a plurality of first piezoresistors, a first metal lead and a first glass substrate, wherein the first silicon strain film is a silicon film which is formed by etching the back surface of a first SOI (silicon on insulator) silicon wafer and is provided with a first island and a first cavity on the back surface, the first island is positioned in the first cavity, and the first glass substrate and the back surface of the first silicon wafer are bonded to seal the first cavity; the first piezoresistors and the first metal leads form a Wheatstone bridge and are positioned on the front surface of the first silicon strained film, and meanwhile, the first piezoresistors are positioned on the edge of the first silicon strained film;
the second piezoresistive pressure sensor comprises a second silicon strain film, a plurality of second piezoresistors, a second metal lead and a second glass substrate, wherein the second silicon strain film is a silicon film which is formed by etching the back surface of a second SOI silicon wafer and is provided with a second island and a second cavity on the back surface, and the second island is positioned in the second cavity; the second glass substrate is bonded with the back surface of the second silicon wafer to seal a second cavity; the plurality of second piezoresistors and the second metal lead form a Wheatstone bridge and are positioned on the front surface of the first silicon strained film, and meanwhile, the second piezoresistors are positioned on the inner edge of the second silicon strained film;
the thickness of the first silicon strain film is the same as that of the second silicon strain film, and the area of the first silicon strain film is larger than that of the second silicon strain film; the thickness of the first island is the same as that of the second island, and the cross-sectional area of the first island is larger than that of the second island;
the silicon cap is bonded with the front surface of the first silicon strain film and forms a containing cavity with the first silicon strain film, the first piezoresistors and the first metal lead are located at the bottom of the containing cavity, and at least one through hole is formed in the silicon cap at the top of the containing cavity.
In a preferable scheme, the cavity can filter an explosion field shock wave pressure signal with frequency greater than f, wherein f satisfies formula (1);
in formula (1):
c is the speed of sound, m/s;
n is the number of the through holes, and n is more than or equal to 1;
r is the radius of the through hole, m;
a is the bottom area in the cavity, m2 ；
H1 Is the axial length of the through hole, m;
H2 m is the height from the bottom to the top in the cavity.
Further, the first SOI silicon wafer and the second SOI silicon wafer are of an integrated structure.
Further, the first glass substrate and the second glass substrate are of an integrated structure.
Optionally, the first silicon strained film is circular or rectangular, and the second silicon strained film is circular or rectangular; the first island is a cylinder or a square column, and the second island is a cylinder or a square column.
Further, the plurality of first piezoresistors are distributed in parallel, wherein two piezoresistors are arranged at the edge of the first silicon strain film; the plurality of second piezoresistors are distributed in parallel, wherein two piezoresistors are arranged at the edge of the second silicon strain film.
Optionally, the number of the first piezoresistors is four; the number of the second piezoresistors is four.
Optionally, two through holes are formed in the silicon cap at the top of the cavity, the two through holes are respectively arranged along the outer edge of the first silicon strain film, and the first silicon strain film is located between the two through holes.
The invention also provides a preparation method of the explosion field MEMS piezoresistive pressure sensor. The provided method comprises the following steps:
(1) preparing a plurality of piezoresistors and metal wires on the front surface of the first silicon chip and the front surface of the second silicon chip respectively, and forming a Wheatstone bridge;
(2) photoetching and etching cavities and islands on the back of the first silicon wafer and the back of the second silicon wafer respectively to form silicon strain films;
(3) etching areas corresponding to the cavities on the front surface of the first glass substrate and the front surface of the second glass substrate respectively;
(4) bonding the front surface of the first glass substrate and the back surface of the first silicon wafer to form a first cavity, and bonding the front surface of the second glass substrate and the back surface of the second silicon wafer to form a second cavity;
(5) and etching a through hole on the silicon cap, and bonding the silicon cap with the front surface of the first silicon wafer.
Further, in the step (1), a plurality of piezoresistors and metal wires are prepared by adopting photoetching, etching, ion doping and LPCVD (low pressure chemical vapor deposition) processes, and a Wheatstone bridge is formed.
The pressure sensor comprises two sensitive membranes with different sizes, wherein the smaller silicon strain membrane can be designed into a structure with smaller sensitivity and larger measuring range, has stronger overload capacity and meets the measurement of the pressure peak value of the shock wave; in addition, a silicon cap with a through hole is arranged above the larger silicon strain film, the cap and the corresponding silicon strain film form a cavity, and shock wave pressure signals with high-frequency characteristics can be filtered by reasonably designing the volume of the air hole and the cavity, so that quasi-static pressure signals with low frequency and zero frequency act on the corresponding silicon strain film; and moreover, the back surfaces of the two sensitive membranes are respectively provided with an island, when the pressure exceeds the measuring range, the islands can be contacted with the glass substrate, certain overload resistance is realized, and the first silicon strain membrane with high sensitivity and small measuring range is further protected.
Drawings
Fig. 1 is a schematic cross-sectional view of an explosion field MEMS piezoresistive pressure sensor according to the present invention.
Fig. 2 is a schematic structural diagram of a silicon cap of an embodiment.
Fig. 3 is a diagram of a distribution of piezoresistors and metal leads of an example.
FIG. 4 is a schematic diagram of a backside structure of a strained Si film according to an embodiment.
Fig. 5 is a schematic three-dimensional structure of a glass substrate of an embodiment.
FIG. 6 is a schematic diagram of a reference process for manufacturing a sensor according to an embodiment, wherein (a) - (g) are schematic diagrams of results of intermediate steps in sequence.
FIG. 7 is a graph showing simulation results of the sensor according to the embodiment.
Detailed Description
Unless otherwise indicated, the terms or methods herein are understood or implemented using established methods as recognized by one of ordinary skill in the relevant art.
Referring to the attached drawings, the explosion field MEMS piezoresistive pressure sensor comprises two piezoresistive pressure sensors with different silicon strain film areas and a silicon cap;
the two piezoresistive pressure sensors respectively comprise a silicon strain film (4-3; 4-4), a plurality of piezoresistors 2-2, a metal lead 2-1 and aglass substrate 5, wherein the silicon strain film is a silicon film which is formed by etching the back surface of an SOI (silicon on insulator) silicon wafer and is provided with an island (4-1; 4-2) and a cavity on the back surface, the island is positioned in thecavity 6, the glass substrate is bonded with the back surface of the silicon wafer to seal the cavity, the piezoresistors and the metal lead form a Wheatstone bridge and are positioned on the front surface of the silicon strain film, and when the silicon strain film is pressed, the edge position of the film is stressed maximally, so the piezoresistors (2-2) are positioned on the edge of the silicon strain film and are parallel to the edge to ensure the maximal resistance change rate;
for the sake of clear description of the structural differences of the two piezoresistive pressure sensors, the term "first and second" is used herein before the corresponding feature or structural terms, on the basis of which the two piezoresistive pressure sensors are structurally different:
since the quasi-static pressure applied to the first silicon strained film 4-3 is much smaller than the shock wave pressure applied to the second silicon strained film 4-4, the area of the first silicon strained film is larger than that of the second silicon strained film; meanwhile, the first silicon strained film 4-3 and the second silicon strained film 4-4 have the same thickness for convenience of processing.
The first island 4-1 and the second island 4-2 have overload protection function, when the pressure applied to the silicon strain film is too large, the islands can contact with the glass substrate so as to avoid the excessive deformation of the sensitive membrane, and because the shock wave pressure applied to the second silicon strain film is far greater than the quasi-static pressure applied to the first silicon strain film, the cross section area of the first island 4-1 is larger than that of the second island 4-2 so as to ensure the firmness of the second silicon strain film, and the heights/thicknesses of the first island 4-1 and the second island 4-2 are the same;
the front surface of the first silicon strain film is bonded with a silicon cap 1-1, the silicon cap and the first strain film form a cavity, the first piezoresistors and the metal leads are positioned at the bottom of the cavity, at least one through hole 1-2 is formed in the silicon cap at the top of the cavity, two through holes 1-2 are formed in two sides of the top of the silicon cap and are respectively arranged along the outer edges of two sides of the first silicon strain film 4-3, the first silicon strain film is positioned between the two through holes, shock wave airflow can not directly act on the first silicon strain film, and the first silicon strain film can be protected.
When shock wave pressure acts on the sensor, after a shock wave pressure signal acting on the silicon cap 1-1 passes through the through hole 1-2 and the accommodating cavity 1-3, a high-frequency part with the frequency larger than f is filtered, so that only a low-frequency quasi-static pressure signal acts on the first silicon strain film 4-3, the first silicon strain film 4-3 deforms under the action of pressure, along with the strain of the diaphragm, the resistivity of the piezoresistor 2-2 arranged on the first silicon strain film 4-3 changes, the resistance value changes, and finally the output of the Wheatstone bridge changes; the working principle of the second silicon strain film 4-4 is similar to that of the first silicon strain film 4-3, the shock wave pressure signal directly acts on the second silicon strain film 4-4, and finally the magnitude of the external shock wave pressure can be determined by measuring the output of the Steton bridge;
after the shock wave pressure passes through the through hole 1-2, due to the lumen effect, the shock wave pressure signal with high frequency characteristics is filtered, and the quasi-static pressure signal with low frequency is applied to the first silicon strained membrane 4-3. In the preferred scheme, the volume of the through hole 1-2 and the volume of the accommodating cavity 1-3 are reasonably designed to selectively filter and remove the blast field shock wave pressure signal larger than f, wherein f satisfies the formula (1);
wherein c is the sound velocity, m/s; n is the number of the through holes, and n is more than or equal to 1; r is the radius of the through hole, m; a is the bottom area in the cavity, m2 ；H1 Is the axial length of the through hole, m; h2 M is the height from the bottom to the top in the cavity.
In other schemes, the SOI silicon wafer of the piezoresistive pressure sensor in two of the above schemes is of an integral structure, and the two glass substrates are of an integral structure.
In a specific embodiment, the shape of the silicon strained film and the shape of the island may be selected according to the requirement, and are usually square or circular and cylindrical or square-column.
In a specific scheme, the number of the piezoresistors is multiple, and is generally 1-5.
Example (b):
in the embodiment, the first silicon wafer and the second silicon wafer are integrated silicon wafers, the first glass substrate and the second glass substrate are integrated glass substrates, wherein the SOI silicon wafer uses an N-type (100) crystal face double-sided polishing SOI silicon wafer, the silicon cap uses an N-type (100) crystal face double-sided polishing silicon wafer, and the glass substrate uses BF33 glass;
cleaning an SOI silicon wafer by using HF solution, wherein the SOI silicon wafer consists of an upper silicon layer 2-4, a buriedsilicon dioxide layer 3 and asilicon substrate 4, and the upper silicon layer 2-4 and thesilicon substrate 4 are separated by the buriedsilicon dioxide layer 3;
the number n of the through holes on the silicon cap is 2, and the through holes are round holesThe radius r is 2.5 mu m; the bottom area A in the cavity is 6.25 multiplied by 10-6 m2 Axial length H of through hole1 120 μm, height H in the cavity2 280 μm, and f is 740Hz, and the frequency of the explosion shock wave pressure signal is more than 1kHz, so that the shock wave pressure signal of the high-frequency signal with the frequency more than 740Hz can be filtered.
In the embodiment, all the silicon strain films and the islands are square, the side length of the first silicon strain film is 1750 mu m from 4 to 3, and the thickness of the first silicon strain film is 50 mu m; the side length of the second silicon strain film 4-4 is 1000 mu m, and the thickness is 50 mu m; the side length of the first island 4-1 is 500 μm, and the thickness is 400 μm; the side length of the second island 4-2 is 400 μm, and the thickness is 400 μm;
in the embodiment, the distance between two adjacent edges of the first silicon strained film 4-3 and the second silicon strained film 4-4 is 1400 μm;
referring to fig. 6, the specific preparation method includes the following steps:
(1) preparing a plurality of piezoresistors and metal wires on the front surface of a silicon wafer, and forming a Wheatstone bridge of two piezoresistive sensors;
(1.1) growing a 300nm silicon dioxide layer 2-7 on the upper surface of the silicon upper layer 2-4 by thermal oxidation, photoetching to form a region needing doping, and Etching the silicon dioxide layer 2-7 which is not protected by photoresist by using RIE (Reactive Ion Etching) process, as shown in figure 6 (a);
(1.2) carrying out boron ion light doping to form four piezoresistors 2-2, then carrying out annealing to ensure that the boron ion impurity concentration is uniformly distributed, and removing the silicon dioxide layer 2-7, as shown in fig. 6 (b);
(1.3) depositing silicon nitride 2-3 on the upper surface of the upper silicon layer 2-4 by using an LPCVD (Low Pressure Chemical Vapor Deposition) process, and photoetching and etching the silicon nitride to form ohmic contacts, metal leads and pad regions, as shown in fig. 6 (c);
(1.4) photoetching the surface of the silicon nitride layer 2-3 to form an ohmic contact, a metal lead and a pad area, sputtering titanium (Ti) -platinum (Pt) -gold (Au) three-layer metal, and forming an ohmic contact, a metal lead and a pad 2-5 through a stripping process to form a Wheatstone bridge, as shown in figure 6 (d);
(2) photoetching and etching cavities and islands on the back of the silicon wafer:
(2.1) spin-coating aphotoresist 7 on the lower surface of thesilicon substrate 4 and performing photoetching to form a pattern to be etched in the back cavity of the sensor, as shown in fig. 6 (e);
(2.2) Etching the back cavity by using a Deep Reactive Ion Etching (DRIE) process to form a first island 4-1, a second island 4-2, a first silicon strain film 4-3 and a second silicon strain film 4-4;
(3) etching the region of the front surface of theBF33 glass sheet 5 corresponding to the first silicon strain film 4-3 to a depth of 4.5 μm, and etching the region of the second silicon strain film 4-4 to a depth of 1 μm;
(4) bonding the front side of aBF33 glass plate 5 with a silicon substrate 2-4 to form avacuum chamber 6 as shown in FIG. 6 (f);
(5) and photoetching and etching the N-type (100) crystal face double-sided polished silicon wafer to form a through hole 1-2 and a cavity 1-3, and bonding the silicon cap 1-1 and the surface area 2-6 of the upper silicon layer 2-4, as shown in fig. 6(g), so as to prepare the explosion field MEMS piezoresistive pressure sensor of the embodiment.
The overload capability of the first silicon strained film (4-3) and the second silicon strained film (4-4) in the sensor of the above embodiment was simulated using the solid mechanics module in the COMSOL finite element software.
As a result, referring to fig. 7, (a) is a relationship between the stress difference of the first silicon strained film 4-3 and the applied pressure, the design range of the first silicon strained film 4-3 in this embodiment is 1MPa, and in the case of overload protection in this embodiment, when the applied pressure is 4MPa, the stress difference of the diaphragm surface is 458MPa and does not reach the rupture stress of the silicon material, and when overload protection is not performed, the stress difference of the diaphragm surface is 953MPa and exceeds the rupture stress of the silicon material; fig. b shows the relationship between the stress difference of the second silicon strained film 4-4 and the applied pressure, the design range of the second silicon strained film 4-4 in this embodiment is 5MPa, and in the case of the overload protection in this embodiment, when the applied pressure is 15MPa, the stress difference on the surface of the diaphragm is 445MPa, which does not reach the fracture stress of the silicon material, and when the overload protection is not performed, the stress difference on the surface of the diaphragm is 937MPa, which exceeds the fracture stress of the silicon material.
Therefore, the overload capacity of the pressure sensor is effectively improved, the overload capacity of the first silicon strain film is 400% FS, and the overload capacity of the second silicon strain film is 300% FS.
Claims (7)
1. An explosion field MEMS piezoresistive pressure sensor, comprising:
the first piezoresistive pressure sensor comprises a first silicon strain film, a plurality of first piezoresistors, a first metal lead and a first glass substrate, wherein the first silicon strain film is a silicon film which is formed by etching the back surface of a first SOI (silicon on insulator) silicon wafer and is provided with a first island and a first cavity on the back surface, the first island is positioned in the first cavity, and the first glass substrate and the back surface of the first SOI silicon wafer are bonded to seal the first cavity; the first piezoresistors and the first metal leads form a Wheatstone bridge and are positioned on the front surface of the first silicon strain film, and the first piezoresistors are positioned on the edge of the first silicon strain film;
the second piezoresistive pressure sensor comprises a second silicon strain film, a plurality of second piezoresistors, a second metal lead and a second glass substrate, wherein the second silicon strain film is a silicon film which is formed by etching the back surface of a second SOI silicon wafer and is provided with a second island and a second cavity on the back surface, and the second island is positioned in the second cavity; the second glass substrate is bonded with the back of the second SOI silicon wafer to seal a second cavity; the plurality of second piezoresistors and the second metal lead form a Wheatstone bridge and are positioned on the front surface of the second silicon strain film, and meanwhile, the second piezoresistors are positioned on the inner edge of the second silicon strain film;
the thickness of the first silicon strain film is the same as that of the second silicon strain film, and the area of the first silicon strain film is larger than that of the second silicon strain film; the thickness of the first island is the same as that of the second island, and the cross-sectional area of the first island is larger than that of the second island;
the silicon cap is bonded with the front surface of the first silicon strain film and forms a cavity with the first silicon strain film, the first piezoresistors and the first metal lead are positioned at the bottom of the cavity, at least one through hole is formed in the silicon cap at the top of the cavity, when shock wave pressure passes through the through hole, shock wave pressure signals with high-frequency characteristics are filtered due to a pipe cavity effect, and low-frequency quasi-static pressure signals act on the first silicon strain film;
the first SOI silicon chip and the second SOI silicon chip are of an integral structure;
the first glass substrate and the second glass substrate are of an integrated structure;
the first piezoresistors are distributed in parallel, wherein two piezoresistors are arranged at the edge of the first silicon strained film; the plurality of second piezoresistors are distributed in parallel, wherein two piezoresistors are arranged at the edge of the second silicon strain film.
2. The explosion field MEMS piezoresistive pressure sensor according to claim 1, wherein said cavity can filter out explosion field shock wave pressure signals with a frequency greater than f, where f satisfies formula (1);
in formula (1):
c is the speed of sound, m/s;
n is the number of the through holes, and n is more than or equal to 1;
r is the radius of the through hole, m;
a is the bottom area in the cavity, m2 ；
H1 Is the axial length of the through hole, m;
H2 m is the height from the bottom to the top in the cavity.
3. The detonation field MEMS piezoresistive pressure sensor according to claim 1, wherein said first silicon strained membrane is circular or rectangular and said second silicon strained membrane is circular or rectangular; the first island is a cylinder or a square column, and the second island is a cylinder or a square column.
4. The detonation field MEMS piezoresistive pressure sensor according to claim 1, wherein said plurality of first piezoresistors is four; the number of the second piezoresistors is four.
5. The explosion field MEMS piezoresistive pressure sensor according to claim 1, wherein two through holes are opened in the silicon cap at the top of the cavity, and the two through holes are respectively disposed on two sides of the first silicon strained film, and the first silicon strained film is located between the two through holes.
6. A method of making a detonation field MEMS piezoresistive pressure sensor according to any of claims 1 to 5, comprising:
(1) respectively preparing a plurality of piezoresistors and metal wires on the front surface of the first SOI silicon chip and the front surface of the second SOI silicon chip, and forming a Wheatstone bridge;
(2) photoetching and etching cavities and islands on the back of the first SOI silicon chip and the back of the second SOI silicon chip respectively to form a silicon strain film;
(3) etching areas corresponding to the cavities on the front surface of the first glass substrate and the front surface of the second glass substrate respectively;
(4) bonding the front surface of the first glass substrate and the back surface of the first SOI silicon chip to form a first cavity, and bonding the front surface of the second glass substrate and the back surface of the second SOI silicon chip to form a second cavity;
(5) and etching a through hole on the silicon cap, and bonding the silicon cap with the front surface of the first SOI silicon wafer.
7. The method for manufacturing an explosion field MEMS piezoresistive pressure sensor according to claim 6, wherein in step (1), the plurality of piezoresistors and the metal wires are manufactured by photolithography, etching, ion doping and LPCVD processes, and a wheatstone bridge is formed.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110798999.9ACN113483926B (en) | 2021-07-15 | 2021-07-15 | Explosion field MEMS piezoresistive pressure sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110798999.9ACN113483926B (en) | 2021-07-15 | 2021-07-15 | Explosion field MEMS piezoresistive pressure sensor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113483926A CN113483926A (en) | 2021-10-08 |
| CN113483926Btrue CN113483926B (en) | 2022-09-23 |
Family
ID=77939465
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110798999.9AActiveCN113483926B (en) | 2021-07-15 | 2021-07-15 | Explosion field MEMS piezoresistive pressure sensor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113483926B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115127717B (en)* | 2022-06-28 | 2025-08-19 | 青岛歌尔智能传感器有限公司 | Pressure sensor |
Citations (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103278270A (en)* | 2013-06-05 | 2013-09-04 | 厦门大学 | Silicon-glass micro pressure sensor chip of island membrane self-packaging structure and manufacturing method |
| CN103674397A (en)* | 2013-12-03 | 2014-03-26 | 新会康宇测控仪器仪表工程有限公司 | High-overload back pressure type absolute-pressure sensor module and manufacturing technology thereof |
| CN104062059A (en)* | 2014-06-13 | 2014-09-24 | 浙江工业大学 | MEMS piezoresistive pressure sensor and manufacturing method thereof |
| CN108401558B (en)* | 2012-12-26 | 2015-01-07 | 北京理工大学 | A kind of zero adjustable height shock transducer chip and preparation method thereof |
| CN104296899A (en)* | 2014-09-28 | 2015-01-21 | 缪建民 | High-sensitivity silicon piezoresistance pressure sensor and preparation method thereof |
| US9383270B1 (en)* | 2013-10-28 | 2016-07-05 | Sandia Corporation | Silicon force sensor |
| CN106066219A (en)* | 2015-04-24 | 2016-11-02 | 浙江盾安人工环境股份有限公司 | Piezoresistive pressure sensor and preparation method thereof |
| CN106644231A (en)* | 2016-12-08 | 2017-05-10 | 西安近代化学研究所 | Effect target structure for measuring peak value of impact wave pressure of movable target, and testing method |
| US10119872B1 (en)* | 2017-12-07 | 2018-11-06 | Hohai University | Temperature interference-free sensing fiber monitoring apparatus and application method therefor |
| CN110371921A (en)* | 2019-07-17 | 2019-10-25 | 西安交通大学 | Twin shaft pressure drag acceleration sensor chip and preparation method thereof in a kind of face |
| CN110550598A (en)* | 2019-09-04 | 2019-12-10 | 中国科学院电子学研究所 | resonant differential pressure sensor and preparation method thereof |
| CN111122044A (en)* | 2019-11-27 | 2020-05-08 | 苏州长风航空电子有限公司 | Airborne aviation high-sensitivity output pressure chip and preparation method thereof |
| WO2020133732A1 (en)* | 2018-12-25 | 2020-07-02 | 中芯集成电路（宁波）有限公司 | Packaging method and packaging structure |
| CN111430334A (en)* | 2020-04-28 | 2020-07-17 | 罕王微电子（辽宁）有限公司 | MEMS 5G communication radio frequency antenna and manufacturing process |
| CN111591952A (en)* | 2020-04-22 | 2020-08-28 | 北京大学 | MEMS piezoresistive pressure sensor and preparation method thereof |
| CN111707404A (en)* | 2020-05-28 | 2020-09-25 | 西安交通大学 | A kind of high temperature resistant silicon carbide pressure sensor and preparation method thereof |
| CN211954507U (en)* | 2020-06-22 | 2020-11-17 | 明石创新(烟台)微纳传感技术研究院有限公司 | Beam island membrane piezoresistive 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 |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102156012A (en)* | 2011-03-15 | 2011-08-17 | 迈尔森电子（天津）有限公司 | Micro electromechanical system (MEMS) pressure sensor and manufacturing method thereof |
| US9816889B2 (en)* | 2015-01-30 | 2017-11-14 | Omega Engineering, Inc. | Differential pressure sensing device with overload protection |
| US10794777B2 (en)* | 2017-06-21 | 2020-10-06 | University Of Florida Research Foundation, Incorporated | Passive wireless pressure sensor for harsh environments |
- 2021
- 2021-07-15CNCN202110798999.9Apatent/CN113483926B/enactiveActive
Patent Citations (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108401558B (en)* | 2012-12-26 | 2015-01-07 | 北京理工大学 | A kind of zero adjustable height shock transducer chip and preparation method thereof |
| CN103278270A (en)* | 2013-06-05 | 2013-09-04 | 厦门大学 | Silicon-glass micro pressure sensor chip of island membrane self-packaging structure and manufacturing method |
| US9383270B1 (en)* | 2013-10-28 | 2016-07-05 | Sandia Corporation | Silicon force sensor |
| CN103674397A (en)* | 2013-12-03 | 2014-03-26 | 新会康宇测控仪器仪表工程有限公司 | High-overload back pressure type absolute-pressure sensor module and manufacturing technology thereof |
| CN104062059A (en)* | 2014-06-13 | 2014-09-24 | 浙江工业大学 | MEMS piezoresistive pressure sensor and manufacturing method thereof |
| CN104296899A (en)* | 2014-09-28 | 2015-01-21 | 缪建民 | High-sensitivity silicon piezoresistance pressure sensor and preparation method thereof |
| CN106066219A (en)* | 2015-04-24 | 2016-11-02 | 浙江盾安人工环境股份有限公司 | Piezoresistive pressure sensor and preparation method thereof |
| CN106644231A (en)* | 2016-12-08 | 2017-05-10 | 西安近代化学研究所 | Effect target structure for measuring peak value of impact wave pressure of movable target, and testing method |
| US10119872B1 (en)* | 2017-12-07 | 2018-11-06 | Hohai University | Temperature interference-free sensing fiber monitoring apparatus and application method therefor |
| WO2020133732A1 (en)* | 2018-12-25 | 2020-07-02 | 中芯集成电路（宁波）有限公司 | Packaging method and packaging structure |
| CN110371921A (en)* | 2019-07-17 | 2019-10-25 | 西安交通大学 | Twin shaft pressure drag acceleration sensor chip and preparation method thereof in a kind of face |
| CN110550598A (en)* | 2019-09-04 | 2019-12-10 | 中国科学院电子学研究所 | resonant differential pressure sensor and preparation method thereof |
| CN111122044A (en)* | 2019-11-27 | 2020-05-08 | 苏州长风航空电子有限公司 | Airborne aviation high-sensitivity output pressure chip and preparation method thereof |
| CN111591952A (en)* | 2020-04-22 | 2020-08-28 | 北京大学 | MEMS piezoresistive pressure sensor and preparation method thereof |
| CN111430334A (en)* | 2020-04-28 | 2020-07-17 | 罕王微电子（辽宁）有限公司 | MEMS 5G communication radio frequency antenna and manufacturing process |
| CN111707404A (en)* | 2020-05-28 | 2020-09-25 | 西安交通大学 | A kind of high temperature resistant silicon carbide pressure sensor and preparation method thereof |
| CN211954507U (en)* | 2020-06-22 | 2020-11-17 | 明石创新(烟台)微纳传感技术研究院有限公司 | Beam island membrane piezoresistive 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 |
Non-Patent Citations (8)
| Title |
|---|
| A high density IC compatible multi-purpose sensor on micro-cavity SOI technology;Mike Myung-Ok Lee 等;《ICVC"97.5th International Conference on VLSI and CAD》;19970101;全文* |
| Piezoresistive pressure sensors for harsh environments;San Hai-sheng 等;《Optics and Precision Engineering》;20120719;第20卷(第3期);全文* |
| 压阻式压力传感器的设计与实验研究;龚雄辉;《中国优秀硕士论文全文数据库 信息科技辑》;20180115(第1期);全文* |
| 基于MEMS压阻传感器的低功耗高过载测试系统设计;韩帅 等;《爆炸与冲击》;20160930;第36卷(第5期);全文* |
| 基于SOI的MEMS高温压阻式压力传感器;单存良 等;《微纳电子技术》;20210430;第58卷(第4期);全文* |
| 微压力传感器参数设计及灵敏度分析;郑玮玮等;《仪表技术与传感器》;20110715(第07期);全文* |
| 耐高温压力传感器的设计研究;陈雨等;《机械设计与制造》;20081008(第10期);全文* |
| 高频响MEMS压力传感器设计与制备;梁庭 等;《仪表技术与传感器》;20210630(第6期);全文* |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113483926A (en) | 2021-10-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5062302A (en) | Laminated semiconductor sensor with overpressure protection | |
| US5220838A (en) | Overpressure-protected, differential pressure sensor and method of making the same | |
| CN111704104B (en) | Method for producing a MEMS pressure sensor and corresponding MEMS pressure sensor | |
| US7998777B1 (en) | Method for fabricating a sensor | |
| US6038928A (en) | Miniature gauge pressure sensor using silicon fusion bonding and back etching | |
| EP2517026B1 (en) | Cmos compatible pressure sensor for low pressures | |
| US7487681B1 (en) | Pressure sensor adjustment using backside mask | |
| CN105000529B (en) | Pressure sensor chip based on MEMS (Micro Electro Mechanical System) technology and manufacturing method thereof | |
| CN113551812A (en) | A cross beam membrane stress concentration micro-pressure sensor chip and preparation method thereof | |
| CN104062464B (en) | MEMS piezoresistive acceleration and pressure integrated sensor and manufacturing method thereof | |
| CN107894294B (en) | Silicon-on-insulator MEMS pressure sensing device with cavity and extended shallow polygonal cavity | |
| CN106092428A (en) | Pressure sensor device with high sensitivity and high accuracy | |
| CN103185613B (en) | Single-silicon-chip micro-flow sensor suitable for surface mounting packaging and manufacturing method thereof | |
| KR20090087847A (en) | Semiconductor photosensitive sensor | |
| CN109809355B (en) | Pressure sensor and method for manufacturing the same | |
| EP0339981A2 (en) | Laminated semiconductor sensor with overpressure protection | |
| CN113218544A (en) | Micro-pressure sensor chip with stress concentration structure and preparation method thereof | |
| CN113483926B (en) | Explosion field MEMS piezoresistive pressure sensor | |
| CN105021328A (en) | Piezoresistive pressure sensor compatible with CMOS process and preparation method of piezoresistive pressure sensor | |
| CN103954383B (en) | A kind of bottom dividing plate microsensor that can be used for the measurement of hot environment lower wall surface shear stress and manufacture method thereof | |
| CN113075726B (en) | Hydrophone and method for manufacturing same | |
| EP1958329B1 (en) | Method of producing surface acoustic wave pressure sensors | |
| US6308575B1 (en) | Manufacturing method for the miniaturization of silicon bulk-machined pressure sensors | |
| CN216669075U (en) | Piezoresistive pressure sensor | |
| RU2478193C1 (en) | Manufacturing method of sensitive element of pressure transducer on ndc-structure |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |