CN111811638A - Piezoelectric type induction unit and hydrophone applying same - Google Patents
Piezoelectric type induction unit and hydrophone applying same Download PDFInfo
- Publication number
- CN111811638A CN111811638A CN201910293027.7A CN201910293027A CN111811638A CN 111811638 A CN111811638 A CN 111811638A CN 201910293027 A CN201910293027 A CN 201910293027A CN 111811638 A CN111811638 A CN 111811638A
- Authority
- CN
- China
- Prior art keywords
- piezoelectric
- layer
- sensing unit
- hydrophone
- hole structure
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 230000006698 induction Effects 0.000 title abstract description 15
- 239000000463 material Substances 0.000 claims description 20
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 14
- 229910052710 silicon Inorganic materials 0.000 claims description 14
- 239000010703 silicon Substances 0.000 claims description 14
- 239000000758 substrate Substances 0.000 claims description 11
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 claims description 8
- PMHQVHHXPFUNSP-UHFFFAOYSA-M copper(1+);methylsulfanylmethane;bromide Chemical compound Br[Cu].CSC PMHQVHHXPFUNSP-UHFFFAOYSA-M 0.000 claims description 6
- HFGPZNIAWCZYJU-UHFFFAOYSA-N lead zirconate titanate Chemical compound [O-2].[O-2].[O-2].[O-2].[O-2].[Ti+4].[Zr+4].[Pb+2] HFGPZNIAWCZYJU-UHFFFAOYSA-N 0.000 claims description 4
- 229910052451 lead zirconate titanate Inorganic materials 0.000 claims description 4
- 239000011787 zinc oxide Substances 0.000 claims description 4
- 238000004519 manufacturing process Methods 0.000 abstract description 19
- 239000004065 semiconductor Substances 0.000 abstract description 15
- 238000005516 engineering process Methods 0.000 abstract description 10
- 230000035945 sensitivity Effects 0.000 abstract description 9
- 238000012545 processing Methods 0.000 abstract description 8
- 230000008859 change Effects 0.000 abstract description 5
- 230000009467 reduction Effects 0.000 abstract description 2
- 239000010410 layer Substances 0.000 description 153
- 238000000034 method Methods 0.000 description 10
- 230000008569 process Effects 0.000 description 8
- 239000011241 protective layer Substances 0.000 description 7
- 238000003475 lamination Methods 0.000 description 5
- 230000008901 benefit Effects 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- 238000011031 large-scale manufacturing process Methods 0.000 description 3
- 239000010409 thin film Substances 0.000 description 3
- 239000013598 vector Substances 0.000 description 3
- -1 LIGA Substances 0.000 description 2
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 2
- 238000004891 communication Methods 0.000 description 2
- 239000004020 conductor Substances 0.000 description 2
- 238000000151 deposition Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005530 etching Methods 0.000 description 2
- 239000000835 fiber Substances 0.000 description 2
- 238000005459 micromachining Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 239000013307 optical fiber Substances 0.000 description 2
- 239000011148 porous material Substances 0.000 description 2
- 230000005236 sound signal Effects 0.000 description 2
- 230000000087 stabilizing effect Effects 0.000 description 2
- PIGFYZPCRLYGLF-UHFFFAOYSA-N Aluminum nitride Chemical compound [Al]#N PIGFYZPCRLYGLF-UHFFFAOYSA-N 0.000 description 1
- 239000004215 Carbon black (E152) Substances 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 238000007792 addition Methods 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 238000003491 array Methods 0.000 description 1
- 230000002238 attenuated effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 229910001385 heavy metal Inorganic materials 0.000 description 1
- 229930195733 hydrocarbon Natural products 0.000 description 1
- 125000001183 hydrocarbyl group Chemical group 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000001459 lithography Methods 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000004377 microelectronic Methods 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 239000003870 refractory metal Substances 0.000 description 1
- 229910021332 silicide Inorganic materials 0.000 description 1
- FVBUAEGBCNSCDD-UHFFFAOYSA-N silicide(4-) Chemical compound [Si-4] FVBUAEGBCNSCDD-UHFFFAOYSA-N 0.000 description 1
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 1
- 229910052721 tungsten Inorganic materials 0.000 description 1
- 239000010937 tungsten Substances 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01H—MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
- G01H11/00—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by detecting changes in electric or magnetic properties
- G01H11/06—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by detecting changes in electric or magnetic properties by electric means
- G01H11/08—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by detecting changes in electric or magnetic properties by electric means using piezoelectric devices
Abstract
The invention discloses a piezoelectric type induction unit and a hydrophone applied by the same, and relates to the field of micro-electromechanical sensors. The sensing unit structure comprises a vacuum vibration cavity, a supporting layer, a piezoelectric seed layer, a piezoelectric main layer, an electrode layer and the like, and realizes that a sensing unit capable of converting underwater sound pressure or vibration into charge change is constructed on a semiconductor layer, in order to increase the sensitivity and reliability of the sensing unit, a plurality of sensing units are connected in parallel or in series, so that a hydrophone can be formed, different numbers of sensing units can be connected according to the performance requirements of the hydrophone, and the consistency and the flexibility of the production of hydrophones with different requirements are ensured; each induction unit realizes miniaturization, light weight and low power consumption, can be produced in a large scale, can effectively improve the sensitivity, simplifies the processing technology under the condition that the physical strength and the voltage resistance of the supporting layer meet the requirements, and realizes the reduction of the production cost.
Description
Technical Field
The invention relates to the field of micro-electro-mechanical systems (MEMS) sensors, in particular to a piezoelectric type sensing unit and a hydrophone applying the same.
Background
Hydrophones, also known as hydrophones or underwater microphones, are transducers used to convert acoustic signals in water into electrical signals. The hydrophone is widely applied to underwater communication, detection, target positioning, tracking and the like, and is an important component of sonar. For example, in marine seismic exploration, a hydrocarbon bearing formation may be located by generating an acoustic source signal within it, which is then detected, at least in part from the acoustic source signal interacting with the layers below the body of water, and must therefore be sensed by a highly accurate hydrophone. MEMS refers to a technology for manufacturing miniaturized mechanical and electromechanical elements using an improved semiconductor device manufacturing technology.
The development directions of hydrophones in recent years are mainly two directions of a fiber optic hydrophone and a traditional piezoelectric hydrophone. The optical fiber hydrophone has the advantages of high sensitivity, interference resistance, small volume, light weight and the like, but is not as good as the traditional piezoelectric hydrophone in the problems of realization difficulty, large-scale production, manufacturing cost and the like of the linear array formed by the optical fiber hydrophones. Many hydrophones include a piezoelectric material that generates an electrical signal when the sound pressure of an acoustic wave deforms the piezoelectric material, which is received by electrodes disposed on either end of the piezoelectric material. The greater the applied acoustic pressure, the stronger the resulting electrical signal will be.
In many cases, hydrophones require good low frequency performance due to large transmission losses and short transmission distances for high frequency signals in the water. In addition, large dynamic range, low acoustic impedance and good linearity are also ideal design criteria for hydrophones. The fiber optic hydrophone structure is overly complex. The piezoelectric ceramic hydrophone contains heavy metals such as lead and the like, and is not environment-friendly. The existing hydrophone also has the problems of high production cost, high volume and weight, high operation consumption, poor consistency and the like.
Disclosure of Invention
In view of the above, the present invention is to realize MEMS semiconductor process-based production, and provide a piezoelectric sensing unit and a hydrophone using the same, which are compact, lightweight, low power consumption, high sensitivity, and capable of mass production and simplified process.
The technical problem to be solved by the invention is realized by the following technical scheme:
a piezoelectric sensing unit, comprising: the piezoelectric element comprises a substrate provided with a hole structure, a supporting layer arranged on the hole structure, and a piezoelectric lamination layer arranged on the supporting layer; the piezoelectric stack comprises a first electrode layer, a piezoelectric seed layer, a piezoelectric main layer and a second electrode layer, and the support layer encloses the hole structure to form a vacuum vibration cavity. The sensing unit further comprises a protective layer arranged on the piezoelectric stack.
In the piezoelectric sensing unit, preferably, the supporting layer is a silicon layer. The silicon layer can be obtained by a relatively simple process and meets the requirements on internal voltage and physical strength.
In the above piezoelectric sensing unit, preferably, the piezoelectric seed layer is disposed on the support layer, the first electrode layer is disposed on the piezoelectric seed layer, the piezoelectric main layer is disposed on the first electrode layer, and the second electrode layer is disposed on the piezoelectric main layer. The piezoelectric seed layer promotes the growth of the first electrode layer and the piezoelectric main layer, so that the piezoelectric lamination is more uniform integrally.
In the above piezoelectric sensing unit, preferably, the thickness of the piezoelectric seed layer is less than 50 nm, and the thickness of the piezoelectric main layer is less than 10 μm. The piezoelectric seed layer of this thickness has no lattice state, promoting the growth of the first electrode layer and the piezoelectric main layer.
In the above piezoelectric sensing unit, preferably, the depth of the pore structure is less than 500 μm. The hole depth of 500 microns is the upper depth limit for matching with the piezoelectric stack, and an excessively long depth will degrade the performance of the sensing unit, typically to a depth of less than 20 microns.
In the piezoelectric sensing unit, preferably, the thickness of the supporting layer is less than 50 micrometers. The thickness of the support layer of 50 microns is the upper limit of the thickness for matching with the piezoelectric stack, and an excessive thickness will reduce the sensitivity of the sensing element, typically to a depth of less than 10 microns.
In the above piezoelectric sensing unit, preferably, the piezoelectric seed layer and the piezoelectric main layer are made of aluminum nitride, zinc oxide, or lead zirconate titanate, and the mechanical vibration is converted into a piezoelectric material with a charge change.
In the piezoelectric sensing unit, preferably, a maximum lattice size difference between the material of the first electrode layer and the material of the piezoelectric seed layer is less than 10%. The first electrode layer and the piezoelectric seed layer have lattices with similar sizes so as to be convenient for growth.
In the above piezoelectric sensing unit, preferably, the boundary of the supporting layer and the edge of the hole structure are similar to each other in a planar pattern and are located on the same central axis, and the area of the boundary of the supporting layer is greater than or equal to 4 times the area of the edge of the hole structure. The physical strength of the support layer is increased.
A hydrophone comprising a plurality of piezoelectric sensing elements as described above, said piezoelectric sensing elements being arranged in an array of a plurality of rows and a plurality of columns, each of said first electrode layers being electrically connected to each other and each of said second electrode layers being electrically connected to each other. And connecting a plurality of induction units on the semiconductor process level to increase the collected electric charge and realize the vector toilet cleaning effect.
Compared with the prior art, the invention has the following advantages:
(1) the invention relates to a piezoelectric type induction unit and a hydrophone constructed based on a micro-electromechanical system, which comprises a vacuum vibration cavity, a supporting layer, a piezoelectric lamination and the like, wherein the piezoelectric lamination also comprises a piezoelectric seed layer, a piezoelectric main layer and an electrode layer, so that the induction unit capable of converting underwater sound pressure or vibration into charge change is constructed on the semiconductor layer, in order to increase the sensitivity and the reliability of the induction unit, a plurality of induction units can be connected in series or in parallel to form a hydrophone, and different numbers of induction units can be connected in series or in parallel according to the performance requirements of the hydrophone.
(2) According to the invention, by setting the depth of the vacuum vibration cavity, the structure of the supporting layer and the structure of the piezoelectric stack, the MEMS processing technology of the induction unit is simplified under the condition that the physical strength and the voltage resistance of the supporting layer meet the requirements, and the reduction of the production cost is realized.
(3) According to the invention, the piezoelectric seed layer which is not in a lattice state is arranged below the first electrode layer and the piezoelectric main layer, so that the piezoelectric seed layer grows uniformly, the overall strength of the piezoelectric lamination is improved, and the yield of the induction device and the hydrophone is increased from about 80% to 95% or above.
(4) The invention adopts the semiconductor integrated circuit processing technology, thus ensuring the production consistency of the hydrophone; each sensing unit is in a micron level, so that miniaturization is realized; each sensing unit is in milligram level in weight, so that the light weight is realized; the power consumption of each induction unit is in the micro watt level, so that low power consumption is realized; more than 2000 detectors can be manufactured on each silicon wafer, and the production cost can be greatly reduced in large-scale production; the piezoelectric material with low dielectric constant is adopted, so that the sensitivity of the sensing unit can be effectively improved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.
FIG. 1 is a schematic structural diagram of a piezoelectric sensing unit according to the present invention;
FIG. 2 is a schematic diagram of the hydrophone structure of the invention.
Graphic notation: the piezoelectric resonator comprises a sensing unit 100, a substrate 110, a hole structure 111, a support layer 120, a piezoelectric stack 130, a piezoelectric seed layer 131, a first electrode layer 132, a piezoelectric main layer 133, a second electrode layer 134, a protective layer 140, a vacuum vibration cavity 150, a bonding 160 and a hydrophone 200.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention and the accompanying drawings.
As shown in fig. 1 and 2, an embodiment of a sensing unit 100 and hydrophone 200 constructed of micro-electro-mechanical systems (MEMS) is shown. Micro-Electro-Mechanical systems, i.e., Micro-Electro-Mechanical systems, refers to a technology for miniaturizing Mechanical and electronic components manufactured using improved semiconductor device manufacturing techniques. In an embodiment, the MEMS element may be comprised of components having dimensions between about 1 micron and 1 millimeter. MEMS is developed based on microelectronics (semiconductor manufacturing technology), and integrates technologies such as lithography, etching, thin film, LIGA, silicon micromachining, non-silicon micromachining, and precision machining to produce high-tech electromechanical devices. The functional elements of the MEMS may include micro-sensors, micro-actuators, micro-mechanical structures, micro-power micro-energy sources, signal processing and control circuits, high performance electronic integrated devices, interfaces, communications, and the like. As shown, a piezoelectric sensing unit 100 can detect sound signals in water and convert the sound signals into electrical signals to determine the source of the sound.
As shown in fig. 1, in one embodiment, the piezoelectric sensing unit 100 includes: a substrate 110 provided with a hole structure 111, a support layer 120 provided on the hole structure 111, a piezoelectric stack 130 provided on the support layer 120; the piezoelectric stack 130 includes a first electrode layer 132, a piezoelectric seed layer 131, a piezoelectric main layer 133, and a second electrode layer 134, and the support layer 120 encloses the hole structure 111 to form a vacuum vibration cavity 150. In this embodiment, the piezoelectric seed layer 131 is disposed on the support layer 120, the first electrode layer 132 is disposed on the piezoelectric seed layer 131, the piezoelectric main layer 133 is disposed on the first electrode layer 132, and the second electrode layer 134 is disposed on the piezoelectric main layer 133. In this embodiment, the support layer 120 may be a silicon layer. In this embodiment, the piezoelectric seed layer 131 and the piezoelectric main layer 133 may be made of aluminum nitride, zinc oxide, lead zirconate titanate, or other suitable piezoelectric materials. In this embodiment, the boundary of the support layer 120 and the edge of the hole structure 111 are similar to a planar pattern and are located on the same central axis. In many embodiments, the protective layer 140 is disposed over the piezoelectric stack 130.
With respect to the overall structure of the sensing unit 100, specifically, the substrate 110 is the base of the sensing unit 100 formed in a semiconductor, the piezoelectric stack 130 is used to convert the underwater sound pressure into an electrical signal, the electrode layer plays a role of conducting the electrical signal, and the support layer 120 plays a role of supporting and stabilizing the piezoelectric stack 130. The support layer 120 and the hole structure 111 in the substrate 110 form a vacuum vibration cavity 150, and the vacuum vibration cavity 150 increases the underwater sound pressure of the piezoelectric stack 130, thereby improving the capability of sensing the underwater sound pressure. Meanwhile, the support layer 120 is subjected to the voltage generated by the charge generated in the piezoelectric stack 130, and needs to meet the requirement of voltage resistance, and the support layer 120 is also subjected to the mechanical pressure generated by the deformation of the piezoelectric stack 130, and needs to meet the requirement of physical strength. The double-layer structure of the piezoelectric seed layer 131 and the piezoelectric main layer 133 improves the uniformity of the piezoelectric stack 130, on one hand, reduces the influence of the local voltage peak on the support layer 120, on the other hand, increases the physical strength of the piezoelectric stack 130 itself, and improves the mechanical pressure resistance of the sensing unit 100 during deformation as a whole. The protective layer 140 serves to protect the sensing unit 100. Finally, the sensing unit 100 achieves the effect of converting the underwater sound pressure into an electrical signal through the vibration of the piezoelectric stack 130 with respect to the vacuum vibration chamber 150 under stable conditions, and conducting the electrical signal to the outside by leading out the electrical signal from the electrodes.
In another embodiment, it is understood that the piezoelectric stack 130 may also be sequentially disposed, from bottom to top, as the first electrode layer 132, the piezoelectric seed layer 131, the piezoelectric main layer 133, the second electrode layer 134 and the protection layer 140.
Specifically, the material of the sensing element 100 is piezoelectric, which generates electricity when deformed. In one embodiment, the piezoelectric seed layer 131 and the piezoelectric main layer 133 may be made of aluminum nitride (AlN), which may convert an acoustic wave signal into an electric signal. In other embodiments, the piezoelectric seed layer 131 and the piezoelectric main layer 133 may be zinc oxide, or other types of piezoelectric materials, such as lead zirconate titanate, which can convert mechanical vibration into a change in charge, and which are suitable for semiconductor processes.
With respect to the material of the sensing unit 100, specifically, the electrode refers to a conductive material applied in a semiconductor process, and can be made of various types of conductors, and the first electrode layer 132 and the second electrode layer 134 can be made of metal (e.g., aluminum), highly doped silicon, refractory metal (e.g., tungsten), silicide, etc., which function to conduct an electrical signal.
As to the material of the sensing unit 100, specifically, the substrate 110 is a physical material for forming the hole structure 111 and forming the vacuum vibration cavity 150 with the support layer 120, and is used for placing or processing a micro-unit or a semiconductor device. In various embodiments, substrate 110 is a silicon wafer used for manufacturing semiconductor devices. The support layer 120 is made of silicon, and plays a role of supporting and stabilizing the sensing unit 100. The support layer 120 may be formed on the hole structure 111 by a thin film process, and the processing environment condition is adjusted to be vacuum, so that the vacuum vibration cavity 150 is formed between the support layer 120 and the hole structure 111 of the substrate 110. The vacuum vibration chamber 150 reduces the acoustic impedance and noise of the sensing cell 100, so that the piezoelectric stack 130 is attenuated less by the pressure received, and also reduces the noise in the vibration signal generated by bombardment caused by random motion in the liquid or gas.
Regarding the material of the piezoelectric stack 130, the maximum lattice size difference between the material of the first electrode layer 132 and the material of the piezoelectric seed layer 131 is less than 10%. The first electrode layer 132 and the piezoelectric seed layer 131 have a lattice of similar dimensions to facilitate growth. Specifically, the piezoelectric seed layer 131 is aluminum nitride, the first electrode layer 132 is made of manganese metal, and since the aluminum nitride and the manganese metal have similar lattice sizes, and the piezoelectric main layer 133 is also made of aluminum nitride, the lattice structures among the piezoelectric seed layer 131, the first electrode layer 132, and the piezoelectric main layer 133 connected in sequence in the piezoelectric stack layer are kept uniform, so that the internal stress is reduced, and the material strength is increased.
Regarding the structure of the sensing unit 100, specifically, the boundary of the support layer 120 is circular, and since the boundary of the support layer 120 and the edge of the hole structure 111 are in a similar planar pattern, the edge of the hole structure 111 is also circular with a smaller diameter. In further embodiments, the boundary shape of the support layer 120 and convenient shape of the aperture structure 111 are square, similar rectangular or similar oval, etc.
In various embodiments, specifically, the hole structures 111 with a depth of less than 20 micrometers are disposed on the substrate 110, the support layer 120 is disposed on a central axis of the hole structures 111, an area of a boundary of the support layer 120 is greater than or equal to 4 times an area of an edge of the hole structures 111, a thickness of the support layer 120 is less than 10 micrometers, the support layer 120 is disposed with a first electrode layer 132, the first electrode layer 132 is deposited with a piezoelectric seed layer 131 with a thickness of less than 50 nanometers, then the piezoelectric main layer 131 is deposited with a thickness of less than 5 micrometers, and finally, the piezoelectric main layer 133 is disposed with a second electrode layer 134 and a protective layer 140, the thickness of the protective layer 140 and the thickness of the support layer 120 are less than 10 micrometers, so as to keep the absorption of the piezoelectric stack 130 to the vibration consistent, wherein the thicknesses of the first electrode layer 132 and the second electrode layer 134 are. In one embodiment, the depth of the pore structure 111 is 15 microns, the thickness of the support layer 120 and the cap layer 140 is 5 microns, the thickness of the piezoelectric seed layer 131 is 40 to 50 microns, and the thickness of the piezoelectric main layer 133 is 3 to 5 microns. The piezoelectric seed layer 131 allows the subsequently deposited piezoelectric main layer 133 to grow more uniformly, the piezoelectric main layer 133 controlling the overall thickness of the piezoelectric stack 130. The overall thickness of the piezoelectric stack 130 interacts with the depth of the vacuum vibration cavity 150, on the one hand increasing the difficulty of voltage breakdown of the support layer 120 and on the other hand controlling the amount of physical deformation and the overall physical strength of the sensing unit 100.
As shown in fig. 2, a hydrophone 200 comprises a plurality of piezoelectric sensing elements 100, wherein the piezoelectric sensing elements 100 are arranged in an array of a plurality of rows and a plurality of columns, the first electrode layers 132 are electrically connected to each other, and the second electrode layers 134 are electrically connected to each other. Specifically, the sensing units 100 are arranged in a 4 × 4 array in a unit of a silicon wafer, and the first electrode layers 132 and the second electrode layers 134 of each sensing unit 100 are connected by wire bonding 160 or a thin film process, and then are connected to elements such as an external amplifier through wires. Although the arrangement in fig. 2 is square, the arrangement may take any form (e.g., circular, octagonal). This arrangement of hydrophones 200 in an array having a plurality of rows and columns allows for the accumulation of individual charges generated by each hydrophone 200. The accumulated charge results in a sufficient amount of charge that can be detected by the preamplifier. In use, the hydrophone 200 collects the charge signals sensed by each of the sensing elements 100 to form an electrical signal sufficient for receipt by an external amplifier. It will be appreciated that by selecting the connections of the local sensing elements 100, a vector sensing of the underwater acoustic signals can be formed, for example, a 16 × 16 array, four of the 4 × 4 arrays are individually connected and led out, so that the simple underwater acoustic signal differences of four quadrants in the 16 × 16 array can be detected, and the hydrophone 200 is mounted on the motion mechanism, so that the detected parameters can be characterized by vectors.
As will be appreciated by those skilled in the art, various fabrication techniques may be used to fabricate the hydrophone 200, as will be appreciated with the benefit of the disclosure of the piezoelectric sensing element 100 and hydrophone 200 embodiments. In one embodiment, the manufacturing process flow: (1) etching a hole structure 111 on a substrate 110 made of silicon, and depositing a siliceous support layer 120 on the hole structure 111 to form a vacuum vibration cavity 150; (2) depositing a piezoelectric seed layer 131, a first electrode layer 132, a piezoelectric main layer 133, a second electrode layer 134 and a silicon protective layer 140 on the support layer 120 in sequence; (3) a plurality of induction units 100 can be efficiently connected in series or in parallel to form a hydrophone 200; (4) different numbers of sensing units 100 may be connected in series or in parallel depending on performance requirements.
In each embodiment, the piezoelectric sensing unit 100 and the hydrophone 200 are based on a micro-electromechanical system structure, so that the sensing unit 100 capable of converting underwater sound pressure or vibration into charge change is constructed on a semiconductor layer, for the sensitivity and reliability of the sensing unit 100, a plurality of sensing units 100 can be connected in series or in parallel to form one hydrophone 200, and different numbers of sensing units 100 can be connected in series or in parallel according to the performance requirements of the hydrophone 200; the semiconductor integrated circuit processing technology is adopted, so that the production consistency of the hydrophone 200 is ensured; each sensing unit 100 is in the micrometer level in size, so that miniaturization is realized; each sensing unit 100 is in milligram level in weight, so that light weight is realized; the power consumption of each sensing unit 100 is in the micro watt level, so that low power consumption is realized; more than 2000 detectors can be manufactured on each silicon wafer, and the production cost can be greatly reduced in large-scale production; the piezoelectric material with low dielectric constant is adopted, so that the sensitivity of the sensing unit 100 can be effectively improved; by setting the depth of the vacuum vibration cavity 150, the structure of the support layer 120, and the structure of the piezoelectric stack, the MEMS processing technology of the sensing unit 100 is simplified and the production cost is reduced under the condition that the physical strength and the voltage resistance of the support layer 120 meet the requirements; the piezoelectric seed layer 131 which is not formed into a lattice state is arranged below the first electrode layer 132 and the piezoelectric main layer 133, so that the growth of the piezoelectric seed layer is uniform, the overall strength of the piezoelectric stack 130 is improved, and the yield of the induction device and the hydrophone 200 is increased from about 80% to 95% or more.
The specific embodiments described herein are merely illustrative of the spirit of the invention. Various modifications or additions may be made to the described embodiments or alternatives may be employed by those skilled in the art without departing from the spirit or scope of the invention as defined in the appended claims.
While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof.
Claims (10)
1. A piezoelectric sensing unit, comprising: a substrate (110) provided with a hole structure (111), a support layer (120) provided on the hole structure (111), a piezoelectric stack (130) provided on the support layer (120);
the piezoelectric stack (130) comprises a first electrode layer (132), a piezoelectric seed layer (131), a piezoelectric main layer (133) and a second electrode layer (134);
the supporting layer (120) encloses the hole structure (111) to form a vacuum vibration cavity (150).
2. The piezoelectric sensing element according to claim 1, wherein the support layer (120) is a silicon layer.
3. The piezoelectric sensing unit according to claim 1, wherein the piezoelectric seed layer (131) is disposed on the support layer (120), the first electrode layer (132) is disposed on the piezoelectric seed layer (131), the piezoelectric main layer (133) is disposed on the first electrode layer (132), and the second electrode layer (134) is disposed on the piezoelectric main layer (133).
4. The piezoelectric sensing unit according to claim 3, wherein the piezoelectric seed layer (131) has a thickness of less than 50 nm and the piezoelectric main layer (133) has a thickness of less than 5 μm.
5. The piezoelectric sensing unit according to claim 4, wherein the depth of the hole structure (111) is less than 500 μm.
6. The piezoelectric sensing element according to claim 4, wherein the thickness of the support layer (120) is less than 50 μm.
7. The piezoelectric sensing element according to claim 3, wherein the piezoelectric seed layer (131) and the piezoelectric main layer (133) are made of aluminum nitride, zinc oxide or lead zirconate titanate.
8. The piezoelectric sensing unit according to claim 7, wherein the maximum lattice size difference between the material of the first electrode layer (132) and the material of the piezoelectric seed layer (131) is less than 10%.
9. The piezoelectric sensing unit according to claim 1, wherein the boundary of the support layer (120) and the edge of the hole structure (111) are similar to each other in a planar pattern and are located on the same central axis, and the area of the boundary of the support layer (120) is greater than or equal to 4 times the area of the edge of the hole structure (111).
10. A hydrophone comprising a plurality of piezoelectric sensing elements according to any of claims 1 to 6, wherein the piezoelectric sensing elements (100) are arranged in an array of a plurality of rows and a plurality of columns, the first electrode layers (132) being electrically connected to each other and the second electrode layers (134) being electrically connected to each other.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910293027.7A CN111811638A (en) | 2019-04-12 | 2019-04-12 | Piezoelectric type induction unit and hydrophone applying same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910293027.7A CN111811638A (en) | 2019-04-12 | 2019-04-12 | Piezoelectric type induction unit and hydrophone applying same |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111811638A true CN111811638A (en) | 2020-10-23 |
Family
ID=72843863
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910293027.7A Pending CN111811638A (en) | 2019-04-12 | 2019-04-12 | Piezoelectric type induction unit and hydrophone applying same |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111811638A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112683388A (en) * | 2021-01-13 | 2021-04-20 | 山东省科学院海洋仪器仪表研究所 | Circular tube vector hydrophone |
| CN114034377A (en) * | 2021-09-28 | 2022-02-11 | 青岛国数信息科技有限公司 | Double-layer AIN piezoelectric film hydrophone chip unit, chip and hydrophone |
| CN114034370A (en) * | 2021-09-28 | 2022-02-11 | 青岛国数信息科技有限公司 | AIN piezoelectric film hydrophone chip unit, chip and hydrophone |
| CN115425391A (en) * | 2022-09-22 | 2022-12-02 | 安徽大学 | Ceramic piezoelectric underwater detection and 5G mobile phone antenna |
| CN115507938A (en) * | 2022-11-16 | 2022-12-23 | 青岛国数信息科技有限公司 | Piezoelectric MEMS hydrophone with pressure-resistant structure |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20140230557A1 (en) * | 2013-02-20 | 2014-08-21 | Agency for Science Technology and Research (A"STAR) | Sensor with vacuum-sealed cavity |
| US20150145374A1 (en) * | 2013-11-26 | 2015-05-28 | Agency For Science, Technology And Research | Transducer and method for forming the same |
| CN107438213A (en) * | 2017-06-06 | 2017-12-05 | 纽威仕微电子（无锡）有限公司 | A kind of hydrophone and its manufacturing process |
| CN109244232A (en) * | 2018-09-13 | 2019-01-18 | 徐景辉 | MEMS PZT (piezoelectric transducer) and production method |
-
2019
- 2019-04-12 CN CN201910293027.7A patent/CN111811638A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20140230557A1 (en) * | 2013-02-20 | 2014-08-21 | Agency for Science Technology and Research (A"STAR) | Sensor with vacuum-sealed cavity |
| US20150145374A1 (en) * | 2013-11-26 | 2015-05-28 | Agency For Science, Technology And Research | Transducer and method for forming the same |
| CN107438213A (en) * | 2017-06-06 | 2017-12-05 | 纽威仕微电子（无锡）有限公司 | A kind of hydrophone and its manufacturing process |
| CN109244232A (en) * | 2018-09-13 | 2019-01-18 | 徐景辉 | MEMS PZT (piezoelectric transducer) and production method |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112683388A (en) * | 2021-01-13 | 2021-04-20 | 山东省科学院海洋仪器仪表研究所 | Circular tube vector hydrophone |
| CN112683388B (en) * | 2021-01-13 | 2023-02-03 | 山东省科学院海洋仪器仪表研究所 | Circular tube vector hydrophone |
| CN114034377A (en) * | 2021-09-28 | 2022-02-11 | 青岛国数信息科技有限公司 | Double-layer AIN piezoelectric film hydrophone chip unit, chip and hydrophone |
| CN114034370A (en) * | 2021-09-28 | 2022-02-11 | 青岛国数信息科技有限公司 | AIN piezoelectric film hydrophone chip unit, chip and hydrophone |
| CN114034377B (en) * | 2021-09-28 | 2024-03-22 | 青岛国数信息科技有限公司 | Double-layer AIN piezoelectric film hydrophone chip unit, chip and hydrophone |
| CN115425391A (en) * | 2022-09-22 | 2022-12-02 | 安徽大学 | Ceramic piezoelectric underwater detection and 5G mobile phone antenna |
| US11750301B1 (en) | 2022-09-22 | 2023-09-05 | Anhui University | Ceramic piezoelectric underwater detection and 5th generation mobile phone antenna |
| CN115507938A (en) * | 2022-11-16 | 2022-12-23 | 青岛国数信息科技有限公司 | Piezoelectric MEMS hydrophone with pressure-resistant structure |
| CN115507938B (en) * | 2022-11-16 | 2023-03-07 | 青岛国数信息科技有限公司 | Piezoelectric MEMS hydrophone with pressure-resistant structure |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN210120666U (en) | Piezoelectric MEMS transducer and electronic device | |
| CN111811638A (en) | Piezoelectric type induction unit and hydrophone applying same | |
| US9809444B2 (en) | System and method for a differential comb drive MEMS | |
| CN212519426U (en) | Piezoelectric microelectromechanical acoustic transducer and electronic device | |
| CN109244232B (en) | Piezoelectric transducer of micro-electromechanical system and manufacturing method | |
| US11159895B2 (en) | Piezoelectric type and capacitive type combined MEMS microphone | |
| US10433068B2 (en) | MEMS acoustic transducer with combfingered electrodes and corresponding manufacturing process | |
| CN209897223U (en) | MEMS microphone | |
| US20150251285A1 (en) | Support structure and method of forming a support structure | |
| US10626007B2 (en) | Microelectromechanical transducer | |
| KR20150105234A (en) | Single diaphragm transducer structure | |
| CN110475191A (en) | A kind of low air damping MEMS piezoelectric microphone | |
| CN101835079A (en) | Capacitance type minitype silicon microphone and preparation method thereof | |
| CN109511023A (en) | A kind of piezoelectric microphones and production method of high sensitivity | |
| CN111770422A (en) | Cascaded miniature microphone and manufacturing method thereof | |
| US10123131B2 (en) | Microelectromechanical microphone with differential capacitive sensing | |
| CN112565948B (en) | Micro-electromechanical system microphone and manufacturing method thereof | |
| KR102367922B1 (en) | Piezoelectric Micro-Electro Mechanical Systems vector hydrophone equipment and Method for manufacturing the same | |
| CN112565947B (en) | Micro-electromechanical system microphone and manufacturing method thereof | |
| CN212435926U (en) | Cascade miniature microphone | |
| CN114112010A (en) | Acoustic measurement unit and device for ultra-low frequency underwater acoustic signal detection | |
| CN114014254A (en) | MEMS structure | |
| CN113301484A (en) | MEMS structure and manufacturing method thereof | |
| CN214960116U (en) | MEMS structure | |
| CN216792269U (en) | Piezoelectric type MEMS acceleration sensor |
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 | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20201023 |