CN114535038A - Transducer unit, array, preparation method and energy equipment - Google Patents
Transducer unit, array, preparation method and energy equipment Download PDFInfo
- Publication number
- CN114535038A CN114535038A CN202210192486.8A CN202210192486A CN114535038A CN 114535038 A CN114535038 A CN 114535038A CN 202210192486 A CN202210192486 A CN 202210192486A CN 114535038 A CN114535038 A CN 114535038A
- Authority
- CN
- China
- Prior art keywords
- transducer
- central
- ring
- electrode layer
- layer
- 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.)
- Granted
Links
- 238000002360 preparation method Methods 0.000 title claims abstract description 15
- 239000000758 substrate Substances 0.000 claims abstract description 9
- 238000005530 etching Methods 0.000 claims description 10
- 230000000149 penetrating effect Effects 0.000 claims 1
- 230000035945 sensitivity Effects 0.000 abstract description 10
- 239000010410 layer Substances 0.000 description 108
- 239000000463 material Substances 0.000 description 18
- 239000012528 membrane Substances 0.000 description 12
- 238000000034 method Methods 0.000 description 11
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 10
- 239000010703 silicon Substances 0.000 description 10
- 238000013461 design Methods 0.000 description 8
- 229910052710 silicon Inorganic materials 0.000 description 8
- 230000005540 biological transmission Effects 0.000 description 7
- 238000006073 displacement reaction Methods 0.000 description 7
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 description 6
- 239000011800 void material Substances 0.000 description 6
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 5
- PMHQVHHXPFUNSP-UHFFFAOYSA-M copper(1+);methylsulfanylmethane;bromide Chemical compound Br[Cu].CSC PMHQVHHXPFUNSP-UHFFFAOYSA-M 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- 238000001755 magnetron sputter deposition Methods 0.000 description 4
- 239000002356 single layer Substances 0.000 description 4
- 239000000919 ceramic Substances 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 3
- 239000002131 composite material Substances 0.000 description 3
- 238000000708 deep reactive-ion etching Methods 0.000 description 3
- 238000002955 isolation Methods 0.000 description 3
- 238000001259 photo etching Methods 0.000 description 3
- 229910052814 silicon oxide Inorganic materials 0.000 description 3
- 239000011787 zinc oxide Substances 0.000 description 3
- 238000001514 detection method Methods 0.000 description 2
- 238000001312 dry etching Methods 0.000 description 2
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 2
- 229910052737 gold Inorganic materials 0.000 description 2
- 239000010931 gold Substances 0.000 description 2
- 230000005484 gravity Effects 0.000 description 2
- 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 description 2
- 229910052451 lead zirconate titanate Inorganic materials 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 2
- 238000005498 polishing Methods 0.000 description 2
- 230000008054 signal transmission Effects 0.000 description 2
- 235000012239 silicon dioxide Nutrition 0.000 description 2
- 239000000377 silicon dioxide Substances 0.000 description 2
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 1
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 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
- 230000008878 coupling Effects 0.000 description 1
- 230000001808 coupling effect Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000002059 diagnostic imaging Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 239000007772 electrode material Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007717 exclusion Effects 0.000 description 1
- 230000006870 function Effects 0.000 description 1
- 238000003384 imaging method Methods 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 238000001459 lithography Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 238000004377 microelectronic Methods 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 229910052750 molybdenum Inorganic materials 0.000 description 1
- 239000011733 molybdenum Substances 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 230000003071 parasitic effect Effects 0.000 description 1
- 230000008447 perception Effects 0.000 description 1
- 238000000206 photolithography Methods 0.000 description 1
- 229910052697 platinum Inorganic materials 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 229910052718 tin Inorganic materials 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B06—GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS IN GENERAL
- B06B—METHODS OR APPARATUS FOR GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS OF INFRASONIC, SONIC, OR ULTRASONIC FREQUENCY, e.g. FOR PERFORMING MECHANICAL WORK IN GENERAL
- B06B1/00—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency
- B06B1/02—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy
- B06B1/06—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction
- B06B1/0607—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction using multiple elements
Abstract
The invention discloses an energy transducer unit, an array, a preparation method and energy equipment, wherein the energy transducer unit comprises a substrate structure and a vibration structure, and the vibration structure comprises a central structure; the ring structure is provided with a gap in a closed manner along the circumferential direction, the gap penetrates through the main body of the ring structure in the direction perpendicular to the circumferential direction, the central structure is arranged in the gap of the ring structure, and a gap is formed between the central structure and the ring structure; and a first connecting structure connecting the central structure and the ring structure; the central structure and the ring structure are both multilayer structures, the central structure and the ring structure are at least provided with a second electrode layer, a piezoelectric layer and a first electrode layer in sequence along the direction deviating from the base structure, and the area of the first electrode layer in the central structure is not larger than that of the piezoelectric layer. The invention effectively improves the performances of sensitivity, propagation distance, output and the like by optimizing the vibration film structure of the transducer.
Description
Technical Field
The present invention relates to microelectronic system technology, and more particularly, to a transducer unit, an array, a method of manufacturing, and an energy device.
Background
The piezoelectric ultrasonic transducer can realize the mutual conversion of electric energy and mechanical energy, and further realize the functions of transmitting and receiving ultrasonic waves. The traditional ultrasonic transducer mostly adopts a mechanical processing mode, but the transducer has larger volume and higher power consumption and is not easy to integrate. The micro-electromechanical ultrasonic transducer is divided into a piezoelectric type ultrasonic transducer and a capacitance type ultrasonic transducer, the capacitive type ultrasonic transducer needs direct current bias voltage for working, the sound velocity of a traditional piezoelectric type ultrasonic transducer adopting materials for parasitic capacitance is low, the integral acoustic sensitivity of a mechanism is low, and the difference between the impedance and the impedance value of a transmission medium is large, so that the transmitting efficiency of the transducer is low. The micro-electromechanical piezoelectric ultrasonic transducer has excellent stability, higher sensitivity, small volume and easy integration. The method is applied to the fields of distance measurement, obstacle identification, space perception, medical imaging and the like.
Most of traditional piezoelectric ultrasonic transducers are capacitive ultrasonic transducers, and direct-current bias voltage is needed to improve sensitivity. Ultrasonic transducers using piezoelectric ceramics as piezoelectric materials are not easily integrated due to their large size and high power consumption. The resonance frequency of the micro-electromechanical piezoelectric ultrasonic transducer is determined by the area of the vibration film, the smaller the area is, the higher the resonance frequency is, the faster the attenuation is, and when the area of the vibration film is smaller, the vibration displacement of the film is smaller, so that the output sound pressure is low. In the prior art, when the area of a vibration film is small, a piezoelectric ultrasonic transducer with low resonant frequency, high output sound pressure and good sensitivity is difficult to manufacture.
The information disclosed in this background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.
Disclosure of Invention
The invention aims to provide a transducer unit, an array, a preparation method and energy equipment, aiming at the problem that a micro-electromechanical piezoelectric ultrasonic transducer in the prior art is limited by a small area of a vibration film, so that the structure of the vibration film is improved, and the performance of the transducer is effectively improved.
To achieve the above object, an embodiment of the present invention provides a transducer unit including a base structure, a vibrating structure (the vibrating structure satisfies a stress balance requirement as a whole), and the vibrating structure includes: a central structure; the ring structure is provided with a gap in a closed manner along the circumferential direction, the gap penetrates through the main body of the ring structure in the direction perpendicular to the circumferential direction, the central structure is arranged in the gap of the ring structure, and a gap is formed between the central structure and the ring structure; the first connecting structure is connected with the central structure and the ring structure (the first connecting structure can achieve the purposes of electric connection, structural balance and the like); the central structure and the ring structure are of a multilayer structure, at least a second electrode layer, a piezoelectric layer and a first electrode layer are sequentially arranged in the direction deviating from the base structure, and the area of the first electrode layer in the central structure is not larger than that of the piezoelectric layer.
In one or more embodiments of the invention, a transducer unit comprises a base structure, a vibrating structure, the vibrating structure comprising: a central structure; the ring structures are arranged around the outer side of the central structure and are spaced from the central structure at a certain distance so as to realize a concentric structure, namely the ring structures are symmetrical rings and have a common center with the central structure; a first connecting structure connecting the central structure and the ring structure; the central structure and the ring structure are of a multilayer structure, at least a second electrode layer, a piezoelectric layer and a first electrode layer are sequentially arranged in the direction deviating from the base structure, and the area of the first electrode layer in the central structure is not larger than that of the piezoelectric layer.
In one or more embodiments of the present invention, the first connection structure at least satisfies the connection between the central structure and the ring structure, and may also have a multilayer structure, that is, may also form a two-layer electrical connection structure and an isolation structure between the two-layer electrical connection structures corresponding to the three-layer structure of the second electrode layer, the piezoelectric layer, and the second electrode layer; preferably, a multilayer structure of the same material may be used for the second electrode layer, the piezoelectric layer, and the second electrode layer.
In one or more embodiments of the invention, in the central structure: the radius of the first electrode layer is 0.55-0.70 times the radius of the piezoelectric layer. Preferably, in the central structure: the radius of the first electrode layer is 0.66 times of the radius of the piezoelectric layer, so that the electromechanical coupling effect is optimal, the vibration displacement is maximum, and the output sound pressure is maximum.
In one or more embodiments of the present invention, in order to satisfy transmission of an electrical signal or current, etc., the transducer unit may further include an electrode lead structure to enable electrical signal exchange with the second electrode layer and the first electrode layer, etc., thereby satisfying input/output of a detection signal, a conversion current, an operation current, etc.
In one or more embodiments of the invention, the outer periphery of the central structure and/or the outer periphery of the ring structure is circular or polygonal. The polygon includes, but is not limited to, a polygon whose sides are line segments, and a polygon whose sides are curved lines. The polygons of line segments include, without limitation, triangles, squares, and the like. The side of the polygon with the curved side can be a circular arc or a wavy line, for example.
In one or more embodiments of the present invention, the central structure and the ring structure are concentrically arranged (may be concentric with the center of mass, concentric with the center of gravity, etc.) to meet the stress balance requirement.
In one or more embodiments of the present invention, the ring structure includes a plurality of ring unit structures, and at least a part of the plurality of ring unit structures have a gap therebetween.
In one or more embodiments of the present invention, the multi-layered structure of the central structure and the ring structure in the transducer unit may further include a support structure formed on the base structure, which may be formed with the central support structure and the ring support structure, respectively. The combination of the shape of the central support structure and the ring support structure may be adapted to the shape of the central structure and the ring structure of the second electrode layer. The support structure may be in the form of a base film.
In one or more embodiments of the present invention, a transducer array includes a plurality of transducer units as described above and a plurality of second connection structures electrically connected between the two transducer units.
In one or more embodiments of the invention, each second connection structure electrically connects two adjacent transducer units.
In one or more embodiments of the invention, the plurality of transducer elements are arranged at least partially in an ordered array.
In one or more embodiments of the present invention, in order to satisfy transmission of electrical signals or currents, the transducer array may further include several electrode lead structures to realize electrical signal exchange with the second electrode layer and the first electrode layer, etc., of the array structure, which may be regarded as a whole, so as to satisfy input/output of detection signals, conversion currents, operating currents, etc.
In one or more embodiments of the invention, a method of preparation, including at least preparation of a transducer unit, comprises the steps of: preparing a substrate; sequentially growing a multilayer structure on a substrate, wherein the multilayer structure comprises a second electrode layer and a piezoelectric layer or sequentially grows the second electrode layer, the piezoelectric layer and a first electrode layer; sequentially etching the multilayer structure from the side far away from the substrate side to form a central structure and a ring structure which are arranged in a matched mode; when the multilayer structure does not have the first electrode layer, continuously forming the first electrode layer; on the side remote from the multilayer structure, the substrate is etched to expose the multilayer structure.
In one or more embodiments of the invention, the energy device comprises a transducer element as described above or a transducer array as described above. Including but not limited to sensors, sonar, power equipment, radar, imaging equipment, and other devices that convert mechanical energy and electromagnetic energy into a core.
Compared with the prior art, the transducer unit, the array, the preparation method and the energy equipment provided by the embodiment of the invention adopt the hollowed-out vibration structure design in a targeted manner, and provide the array structure design matched with the hollowed-out structure design, so that the defects of the existing scheme are effectively overcome, and the piezoelectric ultrasonic transducer with lower resonance frequency, higher output sound pressure and good sensitivity is realized. In the same cell or array may be implemented: under the condition of smaller radius of the vibration film, lower resonance frequency can be realized, and farther transmission distance can be achieved; higher vibration displacement, better sensitivity and higher sound pressure output can also be achieved. The invention optimizes the performance of the transducer, and can be at least partially embodied in resonant frequency, propagation performance, sensitivity, output capacity and the like. The center point of the membrane has larger displacement in the vibration state, so higher sound pressure is generated; the ultrasonic wave has lower resonant frequency under the same radius, and is easy to propagate farther.
Drawings
FIG. 1 is a schematic diagram of a transducer unit according to an embodiment of the present invention;
FIG. 2 is a cross-sectional view taken along line A-A of the embodiment of FIG. 1 according to the present invention;
FIG. 3 is a schematic diagram of a transducer unit according to an embodiment of the present invention;
FIG. 4 is a schematic diagram of two possible configurations of a transducer unit according to an embodiment of the invention;
FIG. 5 is a schematic diagram of a structure of a transducer array according to an embodiment of the invention;
fig. 6 is a schematic illustration of the displacement of the center point of the vibrating structure of the transducer unit according to an embodiment of the invention.
Detailed Description
The following detailed description of the present invention is provided in conjunction with the accompanying drawings, but it should be understood that the scope of the present invention is not limited to the specific embodiments.
Throughout the specification and claims, unless explicitly stated otherwise, the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element or component but not the exclusion of any other element or component.
As shown in fig. 1 to 6, in the transducer solution according to the preferred embodiment of the present invention, the transducer unit and the transducer array formed by the transducer unit can provide an improved small-sized vibrating membrane structure, thereby overcoming the problems of high frequency, low output sound pressure and insufficient sensitivity caused by the small-sized vibrating membrane in the prior art. The main structure of the present invention for achieving this object is a vibrating structure composed of a ring structure (including but not limited to a symmetrical annular film form, etc.) and a central structure (including but not limited to a central circular form, etc.) which is fittingly disposed in a hollow of the ring structure, is defined by the ring structure when viewed perpendicularly to the extension plane without direct connection therebetween, and is also a main structure for transmitting ultrasonic waves. The central structure and the ring structure may be electrically connected directly by an additional structure, such as the first connecting structure, etc., existing therebetween.
In keeping with the prior art, the transducer unit or transducer array, etc. of the present invention also comprises a base structure for carrying a supporting vibrating structure (which may be a vibrating membrane) and an electrode lead structure for electrical connection with the vibrating structure for purposes such as signal transmission and current delivery, the electrode lead structure being electrically connected to the second electrode layer and the first electrode layer of the vibrating structure as in the prior art. In order to embody the difference between the present invention and the prior art, the improved vibrating structure mainly embodies the ring structure of the outer layer and the central structure of the inner layer limited in the vacancy of the ring structure. Since the central structure is defined in the central void of the ring structure, there is no direct structural association between the ring structure and the central structure. Of course, in order to satisfy the definition of the connection between the ring structure and the central structure, a first connection structure is formed between the two, thus forming a functional vibration unit.
As an embodiment, fig. 1 shows a top view of one possible transducer unit according to the invention, fig. 1 showing the case where the central structure of the vibrating structure is circular, the corresponding single-layer ring structure is also circular, in a view perpendicular to the plane of the paper, the circular ring structure having a central position forming a void defining the central structure, the void being also circular in view and satisfying that there is no direct connection between the ring structure and the central structure. In order to satisfy balance and information transmission between the two, the first connection structure connects the central structure and the ring structure.
Fig. 2 is a cross-sectional view taken along a-a of fig. 1, and the transducer unit may be composed of a base structure, a vibration structure formed on the base structure, an electrode lead region, and the like. Wherein the vibration structure includes an annular film 20 having a void, and the annular film 20 may be one of ring structures having a void formed at a central position; a central circular membrane 10 located in the void, the central circular membrane 10 being one of the central structures; the membrane beam, which is one of the first connection structures, of the connection ring structure and the center structure is a structure connected between the outer circumference of the central circular membrane 10 and the inner circumference of the annular membrane 20 as shown in fig. 1. The electrode lead area is introduced by the film body portion, which is shown in fig. 1 as being able to be drawn out around the circumference of the annular film 20, forming a first electrode 61 connected to the first electrode layer and a second electrode 41 connected to the second electrode layer. The membrane beam plays the roles of balancing the stress of the vibration structure, supporting linkage, balancing and the like, connects all parts of the vibration structure into a whole, and also provides voltage for the main vibration part or is used for feeding back signals. The base structure may provide support for the overall membrane structure.
As an embodiment, the ring structure and the central structure both have a multilayer structure, and may include the second electrode layer 06, the piezoelectric layer 05, and the first electrode layer 04, and at this time, the second electrode layer 06, the piezoelectric layer 05, and the first electrode layer/upper electrode 04 respectively have a hollow structure, and the hollow structure may be a combination of missing portions located in each layer observed by an observer in fig. 1, and may be a combination of 4 sections of arc structures in fig. 1, and this hollow structure satisfies an isolation requirement between the central structure or the ring structure or the multilayer ring unit structure constituting the ring structure. Similarly, a layer connecting structure satisfying a communicating isolation space may be formed between the second electrode layer/upper electrode 06, the piezoelectric layer, and the hollow structure of the first electrode layer/upper electrode 04 (or between the ring structure and the central structure of each layer). Preferably, the material of each layer connecting structure is the same as the material of the corresponding second electrode layer/upper electrode 06, piezoelectric layer, and first electrode layer/upper electrode 04.
As an embodiment, further defined is in the central structure: the area of the first electrode layer/upper electrode 04 is not greater than the area of the piezoelectric layer. Taking the case shown in fig. 1 as an example, the area herein refers to the projected area of the first electrode layer/upper electrode 04 and the piezoelectric layer in the paper surface direction in the viewer's perspective. Preferably, in the central structure: the radius of the first electrode layer/upper electrode 04 is 0.55-0.70 times the radius of the piezoelectric layer. Further preferably, in the central structure: the radius of the first electrode layer/top electrode 04 is about 0.66 times the radius of the piezoelectric layer, which results in a better vibration mode of the vibrating membrane, with the largest coupling between the electrode dimensions and the first axially symmetric vibration mode.
As an embodiment, the shape of the central structure may be selected in various ways, and as shown in fig. 1 and 3, the ring structure may be a circular ring, a rectangular ring, or other polygonal rings.
As an embodiment, the shape of the central structure may be similar to the shape of the ring structure, such as a combination of a circular central structure and a circular ring structure; it is also possible that the shape of the central structure may not be similar to the shape of the ring structure, such as a combination of a circular central structure and a square ring structure.
As an embodiment, the ring structure may be a single ring, as shown in fig. 1 and 3; as shown in a and B in fig. 4, the ring structure may be composed of a plurality of rings, and in this case, the ring structure may have a structure in which a plurality of unit rings are combined with each other. Fig. 3 shows a case where the center structure of the vibrating structure is rectangular, and the corresponding single-layer ring structure is also rectangular; the a design in fig. 4 shows a two-layer circular ring structure (with a first outer ring 21, a second outer ring 22); the B design in fig. 4 shows a ring structure of a three-layer ring (having a first outer ring 21, a second outer ring 22, a third outer ring 23). Likewise, the remaining 3 leads 81 shown in the figure may not be present when the 3 schemes are run independently.
Preferably, in the case where a plurality of unit rings are combined with each other, the geometric centers of the plurality of rings may coincide; of course, other situations may be selected, and it is sufficient that the center of gravity of the structure obtained by combining the plurality of unit rings coincides with the geometric center (balance is achieved). Of course, in the combination of the plurality of unit rings, each unit ring may be of the same type, such as a circular ring or a square ring; it is of course also possible to choose different types of combinations for each unit ring, for example a combination of circular rings and square rings.
In one embodiment, in the transducer unit, a support structure (support layer) for supporting the vibration structure is formed on a surface of the base structure adjacent to the vibration structure with reference to the central structure and the ring structure, and similarly, a hollow pattern having a central portion and an outer ring structure is formed, and the central support structure and the ring support structure are formed correspondingly. At this time, the shape of the central support structure and the ring support structure may be adapted to the shape and combination form of the second electrode layer/upper electrode 06, and for example, when the second electrode layer/upper electrode 06 has a central circular structure and an outer single-layer circular structure, the central support structure may be cooperatively formed into a circular structure and a ring support structure, and the ring support structure may be a single-layer circular structure, or the like.
Of course, when the transducer unit exists independently, the remaining 3 lead-out portions 81 illustrated in fig. 1 may not exist except for the lead-out portions from which the first electrode 61 and the second electrode 41 are led out.
As shown in fig. 6, the present invention has a larger displacement and a larger output sound pressure compared to the conventional vibrating structure (about 1.7 μm). Compared with the transducer with multiple piezoelectric layers, a closed cavity structure and the like in the prior art, the invention has the advantages of higher vibration displacement, higher output sound pressure and longer transmission distance.
Further, as shown in fig. 5, a transducer array may be obtained by connecting a plurality of transducer elements in combination, including but not limited to the aforementioned, wherein the plurality of transducer elements are integrally connected to each other by using the second connecting structure. The connection can be realized by interconnection between two adjacent transducer units, or by interconnection between non-adjacent transducer units according to requirements. The actual effective area of the vibration film is increased through the combination, and the performance of the transducer in the aspects of resonant frequency, output sound pressure, transmission distance, sensitivity and the like can be further adjusted according to requirements.
Where the array is formed from a plurality of transducer elements, an array having repeatable elements may be employed. As in the case of the 3 x 3 array shown in fig. 5, the electrode lead region may be led out from one of the cells (a possible case of being led out from a transducer cell located in a lower-middle position is shown in fig. 5). At this time, the remaining lead-out portions 81 of the transducer units can play a role in realizing the integral connection of the array structure, and more importantly, realize the symmetrical stress distribution inside the piezoelectric layer material in each part of the structure. A situation with a lead-out 81 between two adjacent transducer units is shown in fig. 5.
Also, the individual transducer elements of one transducer array may be replaced with each other, since the elements of the transducer array have the possibility to be replaced as desired. It may also be a not completely repeatable substitution, as in fig. 5, a specific transducer unit 100 (the transducer unit located in the second row and the second column in the figure) in the transducer array of the 3 x 3 array may be selectively substituted to include, but not limited to, the other cases in fig. 3-4. At this point, the remaining 8 units of the array are repeatedly replaceable units, and a particular transducer unit 100 has no repeatable replacement with the rest. Of course, such non-repeatable alternatives may also be present in terms of size, etc., in addition to the aforementioned shapes. This can occur anywhere in any array.
In one embodiment, the combined arrangement of the multiple transducer units may be in the form of a rectangular factorial array, a circular array, or a staggered array (that is, a form in which two or more adjacent rows in the rectangular factorial array are arranged crosswise to form a repeating structure, and a plurality of repeating structures are arranged repeatedly), or may be in the form of a form in which no repeatable unit is arranged in the combination.
As an embodiment, multiple transducer elements in the same transducer array may be of the same type, i.e. repeatedly combined by the same transducer element. Of course, the transducer elements in the same transducer array may be of different types, and may be formed by combining different transducer elements, such as by combining transducer elements of different sizes or shapes.
As an embodiment, in order to satisfy the transmission of signals including electrical signals, current, etc. of the transducer array, one or more sets of electrode lead structures may be connected on the transducer array corresponding to the second electrode layer/upper electrode 06 and the first electrode layer/upper electrode 04 in a matching manner, each set of electrode lead structures including a first pin electrically connected to the first electrode layer/upper electrode 04 correspondingly and a second pin electrically connected to the second electrode layer/upper electrode 06 correspondingly. The arrangement of the plurality of groups of electrode lead junctions can be comprehensively considered according to various factors such as the scale, the load, the response speed, the precision and the like of the array.
In one embodiment, the material of the piezoelectric layer 05 is adaptable according to the product, and may be selected from aluminum nitride, zinc oxide, lead zirconate titanate piezoelectric ceramics, and the like. Of course, the piezoelectric layer here can be a single component, such as an aluminum nitride piezoelectric layer, a zinc oxide piezoelectric layer, etc.; the piezoelectric layer can also adopt a mixed material layer, such as a material with the mass ratio of 6: 4, the composition of the mixture is not limited to the combination of the two, but can be more combinations, and the mixing ratio of each combination can also be determined according to the requirements of the actual product; the piezoelectric layer can also be a composite layer, such as a multilayer composite layer formed by combining an aluminum nitride piezoelectric layer, a zinc oxide piezoelectric layer, and a lead zirconate titanate piezoelectric ceramic layer, but can also be other types of composite layers including at least one piezoelectric material layer. It should be noted that the layer herein includes not only a continuous planar layer structure, but also a mesh structure, a discontinuous layer structure electrically connected with each other, and the like. As one possible embodiment, as shown in fig. 2, the material of the base layer 01 may be semiconductor silicon; the material of the oxide layer 02 may be silicon oxide; the 03 material of the support layer can be silicon; the 04 material of the second electrode layer/lower electrode may be metal molybdenum; the 05 material of the piezoelectric layer can be scandium-doped aluminum nitride; the material of the first/upper electrode layer 06 may be gold.
In one embodiment, the electrode material of the first electrode layer/upper electrode 04 and the second electrode layer/upper electrode 06 may be adaptively adjusted according to the product, and may be selected from conductive metals such as gold, platinum, aluminum, or tin. In this case, the materials of the first electrode layer/upper electrode 04 and the second electrode layer/upper electrode 06 may be the same or different, so as to meet the design requirements of the product.
In the possible solutions including but not limited to the above-presented, whether it is a transducer unit or a transducer array, the selection of the combination, size, material selection, etc. for each design may depend on the product and the requirements of the product design and application, etc., without departing from the scope of protection claimed by the present invention.
As an embodiment, in the possible solutions including but not limited to the above-mentioned, whether it is a transducer unit or a transducer array, the preparation thereof can be implemented with reference to the following solutions:
the preparation method can be mainly embodied in the preparation of the transducer unit, and the preparation of the transducer array in the same way can be realized by one-step molding by using different photoetching templates or by combining a plurality of molded transducer units:
selecting an SOI silicon chip, thinning and polishing to reach the required thickness;
sequentially growing a lower electrode and a piezoelectric layer by a magnetron sputtering method;
photoetching and dry etching the piezoelectric layer to obtain a required pattern and expose the lower electrode;
etching the lower electrode by a dry method;
etching silicon and silicon dioxide of the SOI silicon chip;
magnetron sputtering an upper electrode;
and etching the back of the silicon wafer by a deep reactive ion etching method, and releasing the film, so that a resonant cavity structure can be formed.
The other preparation method may be mainly embodied in the preparation of the transducer unit, and the preparation of the transducer array in the same way may be formed in one step by using different lithography templates or by combining a plurality of formed transducer units to obtain:
selecting an SOI silicon chip, thinning and polishing to reach the required thickness;
sequentially growing a lower electrode, a piezoelectric layer and an upper electrode by a magnetron sputtering method;
etching the upper electrode by photoetching and dry method to obtain a required pattern and expose the piezoelectric layer;
sequentially etching the piezoelectric layer and the lower electrode by a dry method;
etching silicon and silicon dioxide of the SOI silicon chip;
and etching the back of the silicon wafer by a deep reactive ion etching method, and releasing the film, so that a resonant cavity structure can be formed.
Including but not limited to photolithography, dry etching, magnetron sputtering, deep reactive ion etching, etc. to achieve etching in the above steps may all employ techniques known in the art depending on the product and process being produced.
The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. It is not intended to limit the invention to the precise form disclosed, and obviously many modifications and variations are possible in light of the above teaching. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and its practical application to enable one skilled in the art to make and use various exemplary embodiments of the invention and various alternatives and modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims and their equivalents.
Claims (10)
1. A transducer unit comprising at least a base structure, a vibrating structure arranged at the base structure, characterized in that the vibrating structure comprises:
a central structure; and
a ring structure having a gap formed in a closed manner in a circumferential direction, the gap penetrating a main body of the ring structure in a direction perpendicular to the circumferential direction, the central structure being disposed in the gap of the ring structure, and a gap being formed between the central structure and the ring structure; and
a first connecting structure connecting the central structure and the ring structure;
the central structure and the ring structure are both multilayer structures, the central structure and the ring structure are sequentially provided with at least a second electrode layer, a piezoelectric layer and a first electrode layer along a direction deviating from the base structure, and the area of the first electrode layer in the central structure is not larger than that of the piezoelectric layer.
2. The transducer unit of claim 1, wherein in the central structure: the radius of the first electrode layer is 0.55-0.70 times the radius of the piezoelectric layer.
3. The transducer element of claim 1, wherein the central structure and the ring structure are concentrically arranged.
4. The transducer element of claim 1 or 3, wherein the ring structure comprises a plurality of ring element structures, and wherein at least some of the ring element structures have gaps therebetween.
5. A transducer array comprising a plurality of transducer elements as claimed in any of claims 1 to 4 and a plurality of second connection structures electrically associated with the transducer elements.
6. The transducer array of claim 5, wherein each of the second connection structures electrically connects two adjacent transducer elements.
7. The transducer array of claim 5, wherein at least some of the plurality of transducer elements are arranged in an ordered array.
8. The transducer array of any of claims 5-7, further comprising an electrode lead structure electrically connected to the transducer elements.
9. The preparation method of the transducer unit comprises the following steps:
preparing a substrate;
growing a multilayer structure on a substrate in sequence, wherein the multilayer structure comprises a second electrode layer and a piezoelectric layer or grows the second electrode layer, the piezoelectric layer and a first electrode layer in sequence;
sequentially etching the multilayer structure from the side far away from the substrate side to form a central structure and a ring structure which are arranged in a matched mode; when the multilayer structure does not have the first electrode layer, continuously forming the first electrode layer;
on the side remote from the multilayer structure, the substrate is etched to expose the multilayer structure.
10. Energy device comprising a transducer unit according to any of claims 1-4 or a transducer array according to any of claims 5-8.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210192486.8A CN114535038B (en) | 2022-02-28 | 2022-02-28 | Transducer unit, array, preparation method and energy device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210192486.8A CN114535038B (en) | 2022-02-28 | 2022-02-28 | Transducer unit, array, preparation method and energy device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114535038A true CN114535038A (en) | 2022-05-27 |
| CN114535038B CN114535038B (en) | 2023-07-07 |
Family
ID=81661617
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210192486.8A Active CN114535038B (en) | 2022-02-28 | 2022-02-28 | Transducer unit, array, preparation method and energy device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114535038B (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110560348A (en) * | 2019-08-14 | 2019-12-13 | 武汉大学 | MEMS piezoelectric ultrasonic transducer with hole array Helmholtz resonant cavity |
| CN111050256A (en) * | 2019-12-17 | 2020-04-21 | 武汉大学 | Miniaturized high-sensitivity piezoelectric microphone |
| CN112871614A (en) * | 2021-01-12 | 2021-06-01 | 武汉大学 | MEMS ultrasonic transducer with high emission performance |
| CN113037245A (en) * | 2021-03-11 | 2021-06-25 | 天津大学 | Quartz resonator based on piezoelectric thin film transduction and electronic equipment |
| CN114345675A (en) * | 2022-01-11 | 2022-04-15 | 中国科学院苏州纳米技术与纳米仿生研究所 | Transduction structure, transducer, preparation method and equipment |
-
2022
- 2022-02-28 CN CN202210192486.8A patent/CN114535038B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110560348A (en) * | 2019-08-14 | 2019-12-13 | 武汉大学 | MEMS piezoelectric ultrasonic transducer with hole array Helmholtz resonant cavity |
| CN111050256A (en) * | 2019-12-17 | 2020-04-21 | 武汉大学 | Miniaturized high-sensitivity piezoelectric microphone |
| CN112871614A (en) * | 2021-01-12 | 2021-06-01 | 武汉大学 | MEMS ultrasonic transducer with high emission performance |
| CN113037245A (en) * | 2021-03-11 | 2021-06-25 | 天津大学 | Quartz resonator based on piezoelectric thin film transduction and electronic equipment |
| CN114345675A (en) * | 2022-01-11 | 2022-04-15 | 中国科学院苏州纳米技术与纳米仿生研究所 | Transduction structure, transducer, preparation method and equipment |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114535038B (en) | 2023-07-07 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US11711067B2 (en) | Micromachined ultrasound transducer using multiple piezoelectric materials | |
| US7770279B2 (en) | Electrostatic membranes for sensors, ultrasonic transducers incorporating such membranes, and manufacturing methods therefor | |
| US7612635B2 (en) | MEMS acoustic filter and fabrication of the same | |
| US8456958B2 (en) | Capacitive micro-machined ultrasonic transducer for element transducer apertures | |
| US8004373B2 (en) | MEMS ultrasonic device having a PZT and cMUT | |
| US8148877B2 (en) | Micromachined piezoelectric ultrasound transducer arrays | |
| US6140740A (en) | Piezoelectric transducer | |
| EP2174359A2 (en) | Thin film detector for presence detection | |
| CN110681559B (en) | MEMS piezoelectric ultrasonic transducer with Helmholtz resonant cavity | |
| CN109225789A (en) | A kind of combined variable rigidity film pMUTs and preparation method thereof | |
| CN114486014B (en) | Ultrasonic transducer unit and array combining PMUT with MEMS pressure sensor and manufacturing method | |
| CN109231150A (en) | A kind of combined film pMUTs and preparation method thereof | |
| CN114345675A (en) | Transduction structure, transducer, preparation method and equipment | |
| KR20160011104A (en) | Ultrasonic transducer and method of manufacturing ultrasonic transducer | |
| CN114535038B (en) | Transducer unit, array, preparation method and energy device | |
| CN112452694A (en) | Multi-frequency piezoelectric miniature ultrasonic transducer unit, array and method | |
| WO2009001157A1 (en) | A capacitive micro-machined ultrasonic transducer for element transducer apertures | |
| CN114890372B (en) | Design and preparation method of PMUT with isolation groove | |
| JPS61220596A (en) | Ultrasonic wave transducer | |
| WO2024027730A1 (en) | Micromachined ultrasonic transducer structure having having dual pmuts provided at same side as substrate, and manufacturing method therefor | |
| CN114130636B (en) | Piezoelectric type MEMS ultrasonic transducer | |
| WO2017186796A1 (en) | Cmut transducer array with impedance matching lens | |
| CN115889153A (en) | Multi-electrode driven high-order mode piezoelectric micro-mechanical ultrasonic transducer and application | |
| CN116713172A (en) | Ultrasonic transduction substrate and manufacturing method and equipment thereof | |
| CN117548319A (en) | Micromechanical ultrasonic transducer structure with double PMUTs on bearing layer and manufacturing method thereof |
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 |