WO2014185565A1

WO2014185565A1 - Method for manufacturing transducer and transducer manufactured by method

Info

Publication number: WO2014185565A1
Application number: PCT/KR2013/004286
Authority: WO
Inventors: 김성학; 신은희; 채수평
Original assignee: 알피니언메디칼시스템 주식회사
Priority date: 2013-05-13
Filing date: 2013-05-15
Publication date: 2014-11-20
Also published as: KR101491800B1; KR20140134058A

Abstract

Provided are a method for manufacturing a transducer and a transducer manufactured by the method. The method for manufacturing a transducer comprises the steps of: stacking a first electrode unit on the upper surface of a backing material; stacking a piezoelectric device on the upper surface of the first electrode unit; forming a plurality of filling grooves on the upper surface of the piezoelectric device through a grooving process; and respectively filling up the filling grooves with a polymer while sequentially stacking a second electrode unit and a matching layer on the upper surface of the piezoelectric device.

Description

Transducer manufacturing method and transducer manufactured by the method

The present embodiment relates to a method for manufacturing a transducer, and more particularly, a method of manufacturing a transducer provided in an ultrasonic diagnostic apparatus or the like for acquiring image information inside an object by using ultrasonic waves, and a transducer manufactured by the method. It is about.

The contents described in this section merely provide background information on the embodiments of the present invention and do not constitute a prior art.

The ultrasound diagnosis apparatus transmits an ultrasound signal to a diagnosis site of a test subject by a probe, and then receives an ultrasound signal reflected from a tissue boundary in the test subject having a different acoustic impedance by the probe. Obtain video information. The image information is output to the monitor of the ultrasound diagnosis apparatus, and the diagnoser may perform diagnosis on the subject through the image information output to the monitor. The probe is provided with a transducer for transmitting an ultrasonic signal to the inspected object and receiving an ultrasonic signal reflected from the inspected object.

In general, the transducer has a configuration in which a piezoelectric layer, a matching layer, and the like are stacked on a backing material. The piezoelectric layer is formed of a piezoelectric element made of only a piezoelectric material, or is formed of a piezoelectric composite in which a polymer material is composited in the piezoelectric element in order to increase ultrasonic transmission and reception performance. According to the conventional example, when manufacturing the transducer including the piezoelectric composite, it goes through the following process. After the plurality of filling grooves are cut side by side by a grooving process on the upper surface of the piezoelectric element, the filling grooves are filled with a polymer. Thereafter, the upper and lower surfaces of the piezoelectric element filled with the polymer are polished to make the piezoelectric composite to a predetermined thickness. The piezoelectric composite thus processed is laminated on the backing material.

However, as described above, two polishing operations must be performed in the process of making the piezoelectric composite. This requires a lot of process time and cost to manufacture the transducer. In addition, when the base material of the piezoelectric composite is composed of a piezoelectric single crystal, the single crystal has a high brittleness, which makes it difficult to grind.

An object of the present invention to provide a transducer manufacturing method and a transducer manufactured by the method that can reduce the process time and cost.

Transducer manufacturing method according to the present invention for achieving the above object, the step of laminating the first electrode portion on the upper surface of the backing material; Stacking a piezoelectric element on an upper surface of the first electrode unit; Forming a plurality of filling grooves on a top surface of the piezoelectric element by a grooving process; And filling polymers in the filling grooves while sequentially stacking a second electrode part and a matching layer on the upper surface of the piezoelectric element.

According to the present invention, the process of polishing the upper and lower surfaces of the piezoelectric composite in the process of making the piezoelectric composite can be eliminated, thereby reducing the process time and cost. In addition, due to the omission of the polishing process, not only PZT but also highly brittle piezoelectric single crystals can be applied as a base material of the piezoelectric composite. Therefore, the transducer can be configured to have higher ultrasonic transmission and reception performance.

1 is a flow chart for a transducer manufacturing method according to an embodiment of the present invention.

2 to 7 are perspective views for explaining a process of manufacturing the transducer by the manufacturing method of FIG.

FIG. 8 is a perspective view illustrating another example in which a plurality of filling grooves are formed on an upper surface of the piezoelectric element in FIG. 4.

9 is a flowchart illustrating a transducer manufacturing method according to another embodiment of the present invention.

10 to 13 are perspective views illustrating a process of manufacturing the transducer by the manufacturing method of FIG.

When described in detail with reference to the accompanying drawings for the present invention. Here, the same reference numerals are used for the same components, and repeated descriptions and detailed descriptions of well-known functions and configurations that may unnecessarily obscure the subject matter of the present invention will be omitted. Embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art. Accordingly, the shape and size of elements in the drawings may be exaggerated for clarity.

1 is a flow chart for a transducer manufacturing method according to an embodiment of the present invention. 2 to 7 are perspective views for explaining a process of manufacturing the transducer by the manufacturing method of FIG.

Referring to FIG. 1, in the method of manufacturing a transducer according to an exemplary embodiment of the present disclosure, a step (S110) of stacking a first electrode part on an upper surface of a backing material and a step of stacking a piezoelectric element on a top surface of a first electrode part (S120) ), And forming a plurality of filling grooves side by side by a grooving process on the upper surface of the piezoelectric element (S130), and filling the polymer into the filling grooves while sequentially stacking the second electrode portion and the matching layer on the upper surface of the piezoelectric element. And dividing the matching layer, the second electrode portion, and the piezoelectric element from the upper surface of the matching layer by a dicing process (S140) and forming channel separation grooves between the first electrodes. Forming a corresponding one at every step (S150), and filling the polymer into the channel separation grooves (S160), respectively.

With reference to Figures 2 to 7, with reference to the transducer manufacturing method according to an embodiment of the present invention in more detail as follows.

In step S110, the backing material 110 is provided as shown in FIG. At this time, the backing material 110 may be configured to have sound absorption. The backing material 110 reduces the pulse width of the ultrasonic wave by suppressing free vibration of the piezoelectric element 130 stacked on the upper side, and prevents unnecessary propagation of the ultrasonic wave to the lower side of the piezoelectric element 130 to prevent image distortion. You can prevent it. For example, when the transducer is configured as a linear array type, the backing material 110 may be configured to have a flat top surface. The backing material 110 may be formed of a material filled with a high density powder material such as tungsten (W), lead (Pb), zinc oxide (ZnO), and the like.

Then, the first electrode portion 120 for laminating on the upper surface of the backing material 110 is provided. In this case, the first electrode unit 120 may be configured as a flexible printed circuit board on which the first electrodes 121 are formed in a stripe shape. The lower surface of the first electrode portion 120 may be bonded to the upper surface of the backing material 110 by an adhesive or the like. The first electrodes 121 may be made of conductive metal materials such as copper, gold, and silver, respectively.

In step S120, as shown in FIG. 3, a piezoelectric element 130 is prepared. The piezoelectric element 130 may generate an ultrasonic signal by resonating when a voltage is applied, and generate an electrical signal by vibrating when the ultrasonic signal is received. The piezoelectric element 130 may be formed of a piezoelectric ceramic such as lead zirconate titanate (PZT), piezoelectric single crystal, or the like. In addition, the piezoelectric element 130 may be configured in a form in which electrode layers are formed on the top and bottom surfaces thereof, for example, by deposition. The electrode layer formed on the lower surface of the piezoelectric element 130 may be connected to the first electrode 120, and the electrode layer formed on the upper surface of the piezoelectric element 130 may be connected to the second electrode 140. The piezoelectric element 130 is stacked on the upper surface of the first electrode unit 120. In this case, the lower surface of the piezoelectric element 130 may be bonded to the upper surface of the first electrode part 120 by an adhesive or the like.

In step S130, as shown in FIG. 4, the plurality of filling grooves 131 are formed side by side by a grooving process on the upper surface of the piezoelectric element 130. In this case, the charging grooves 131 are formed in a stripe shape in a direction crossing the first electrodes 121. The filling grooves 131 may be formed to have a predetermined width and a predetermined depth, respectively. When the filling grooves 131 are formed, each bottom surface position of the filling grooves 131 may be set to be the same as the bottom surface position of the piezoelectric element 130. Accordingly, the piezoelectric element 130 has a form in which both portions are separated with the filling groove 131 interposed therebetween.

In step S140, as shown in FIG. 5, the polymer 132 is formed in the filling grooves 131 while sequentially stacking the second electrode part 140 and the matching layer 150 on the upper surface of the piezoelectric element 130. To charge. The second electrode unit 140 may be configured as a flexible printed circuit board having second electrodes (not shown) formed in a stripe shape on a lower surface thereof. The second electrodes may be made of a conductive metal material such as copper, gold, silver, or the like, and may be formed in the same pattern as the first electrodes 121. The lower surface of the second electrode unit 140 may be bonded to the upper surface of the piezoelectric element 130 by using an adhesive or the like. When the first electrodes 121 function as signal electrodes for transmitting and receiving electrical signals, the second electrodes may function as ground electrodes. Of course, the second electrodes may function as signal electrodes, in which case the first electrodes 121 may function as ground electrodes.

The matching layer 150 may be bonded to the upper surface of the second electrode unit 140 with an adhesive or the like. The matching layer 150 may reduce the acoustic impedance difference between the piezoelectric element 130 and the object under test. For example, the matching layer 150 may be formed of an epoxy resin or the like, and may include a plurality of layers. By filling the polymers 132 in the filling grooves 131 of the piezoelectric element 130, the piezoelectric composite may be formed between the first electrode portion 120 and the second electrode portion 140. The polymer 132 may be made of epoxy or the like.

In step S150, as shown in FIG. 6, the matching layer 150, the second electrode part 140, and the piezoelectric element 130 are cut from the upper surface of the matching layer 150 by a dicing process to separate the channel separation grooves. To form 160. In this case, each channel separation groove 160 is formed to correspond to each of the first electrodes 121.

The channel separation grooves 160 may be formed to have a predetermined width and a predetermined depth, respectively. When the channel separation grooves 160 are formed, each bottom depth of the channel separation grooves 160 may be set to be the same as that of the bottom surface of the piezoelectric element 130. Accordingly, the piezoelectric element 130 has a form in which both portions are separated with the channel separation groove 160 therebetween. In addition, by the channel separation grooves 160, the vibration modules constituting each channel may be separated from each other in a stripe pattern on the backing material 110. These vibration modules allow the transducer to be configured to have multiple channels.

In operation S160, as shown in FIG. 7, the polymer 170 is filled in the channel separation grooves 160, respectively. The polymer 170 may mutually support the vibration modules between the vibration modules. An acoustic lens 180 that focuses the ultrasonic waves generated from the piezoelectric element 130 may be disposed on an upper surface of the matching layer 150.

According to the transducer manufacturing method described above, the process of polishing the upper and lower surfaces of the piezoelectric composite in the process of making the piezoelectric composite can be eliminated, thereby reducing the process time and cost. In addition, due to the omission of the polishing process, not only PZT but also highly brittle piezoelectric single crystals can be applied as a base material of the piezoelectric composite. Therefore, the transducer manufactured by the manufacturing method according to an embodiment of the present invention may be configured to have a higher ultrasonic transmission and reception performance.

Meanwhile, in step S130, when forming the filling grooves 131, each bottom position of the filling grooves 131 may be set higher than a lower surface position of the piezoelectric element 130. Accordingly, the piezoelectric element 130 may be formed in a form in which all portions close to the lower surface are continued. Although not shown, when the channel separation grooves 160 are formed in step S150, each bottom surface position of the channel separation grooves 160 may be set lower than a bottom surface position of the piezoelectric element 130.

9 is a flowchart illustrating a transducer manufacturing method according to another embodiment of the present invention. 10 to 13 are perspective views illustrating a process of manufacturing the transducer by the manufacturing method of FIG.

Referring to FIG. 9, the method of manufacturing a transducer according to another exemplary embodiment of the present invention includes stacking a first electrode part on an upper surface of a backing material (S210) and stacking a piezoelectric element on an upper surface of a first electrode part (S220). ), And forming the first filling grooves and the second filling grooves to cross each other by a grooving process on the upper surface of the piezoelectric element (S230), and sequentially laminating the second electrode portion and the matching layer on the upper surface of the piezoelectric element. Filling the polymer into the first and second filling grooves (S240), respectively.

10 to 13, the transducer manufacturing method according to another embodiment of the present invention will be described in detail as follows. Hereinafter, description will be focused on the parts that differ from the above-described embodiment.

In operation S210, as illustrated in FIG. 10, the first electrode unit 220 may be formed of a flexible printed circuit board having first electrodes 221 formed in a stripe shape on an upper surface thereof. In this case, each of the first electrodes 221 may be formed to have a width enough to position at least one of the first charging grooves 231a. In operation S220, as illustrated in FIG. 11, the piezoelectric element 230 is stacked on the upper surface of the first electrode unit 220.

In operation S230, as shown in FIG. 12, the first charging grooves 231a and the second charging grooves 231b are formed to cross each other on the upper surface of the piezoelectric element 230. In this case, the extending direction of the first charging grooves 231a may be set to be the same as the extending direction of the first electrodes 221. At least one first charging groove 231a is formed to correspond to the first electrodes 221, respectively. Therefore, two or more vibration modules are connected to one first electrode 221. When the first and second filling

grooves

231a and 231b are formed, the bottom surface positions of the first and second filling

grooves

231a and 231b may be set to be the same as the bottom surface of the piezoelectric element 230. Of course, each bottom surface of the first charging grooves 231a among the first charging grooves 231a corresponding to the first electrodes 221 may be set higher than the bottom surface of the piezoelectric element 230. Each bottom surface of the first charging grooves 231a positioned between the first electrodes 221 among the first charging grooves 231a may be set lower than the bottom surface of the piezoelectric element 230. In addition, each bottom surface position of the second filling grooves 231b may be set higher than a bottom surface position of the piezoelectric element 230.

In operation S240, as shown in FIG. 13, the first and second filling

grooves

231a and 231b are sequentially stacked with the second electrode part 240 and the matching layer 250 on the top surface of the piezoelectric element 230. The polymer 270 is filled in each. In this case, the second electrodes of the second electrode part 240 may be formed in the same pattern as the first electrodes 221. The acoustic lens 280 may be disposed on the top surface of the matching layer 250.

In the transducer manufacturing method according to the present embodiment, the process of polishing the upper and lower surfaces of the piezoelectric composite in the process of making the piezoelectric composite can be eliminated, thereby reducing the process time and cost. In addition, due to the omission of the polishing process, not only PZT but also highly brittle piezoelectric single crystals can be applied as a base material of the piezoelectric composite.

Although the present invention has been described with reference to one embodiment shown in the accompanying drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. Could be. Accordingly, the true scope of protection of the invention should be defined only by the appended claims.

Claims

Stacking a first electrode on an upper surface of the backing material;

Stacking a piezoelectric element on an upper surface of the first electrode unit;

Forming a plurality of filling grooves on a top surface of the piezoelectric element by a grooving process; And

Filling the filling grooves with a polymer, respectively, by sequentially stacking a second electrode portion and a matching layer on an upper surface of the piezoelectric element;

Transducer manufacturing method comprising a.
The method of claim 1,

Stacking the first electrode unit,

And providing a first printed circuit board on the upper surface of the first electrode part and stacking the first electrode on a top surface of the backing material.
The method of claim 2,

Forming the filling grooves,

And forming the filling grooves in a stripe shape in a direction crossing the first electrodes.
The method of claim 3,

Forming the filling grooves,

And setting the bottom position of each of the filling grooves to be the same or higher than the bottom position of the piezoelectric element.
The method of claim 3,

After each filling the polymer into the filling grooves,

A channel dividing groove is formed by cutting the matching layer, the second electrode part, and the piezoelectric element from an upper surface of the matching layer by a dicing process, and the channel separating grooves correspond to each of the first electrodes. Forming to make; And

Respectively filling polymer into the channel separation grooves;

Transducer manufacturing method comprising a.
The method of claim 2,

Forming the filling grooves,

And forming the first filling grooves and the second filling grooves so as to cross each other, and forming the first filling grooves to correspond to the first electrodes by at least one or more, respectively.
The method of claim 6,

Forming the filling grooves,

And setting the bottom surface positions of the second filling grooves to be the same as or higher than the bottom position of the piezoelectric element.
The method of claim 6,

Forming the filling grooves,

And setting a bottom position of each of the first charging grooves corresponding to the first electrodes among the first charging grooves to be equal to or higher than a lower surface position of the piezoelectric element.
The method of claim 1,

The step of stacking a piezoelectric element on the upper surface of the first electrode portion,

And arranging the piezoelectric element as one selected from a PZT-based piezoelectric ceramic and a piezoelectric single crystal, and stacking the piezoelectric element on an upper surface of the first electrode part.
The transducer manufactured by the manufacturing method in any one of Claims 1-9.