transducer

Abstract

The first connecting portion (130a) connects the first front end portion (122a) and the second front end portion (122b) to each other. The first connecting portion (130a) is surrounded by the partitioning slit (142) that partitions the center (122ac) of the first front end portion (122a) and the center of the base portion and the center of the second front end portion (122b), the first front end portion (122a), and the second front end portion (122b).

Description

TECHNICAL FIELD

[0001] The present application relates to a transducer, and particularly to an acoustic transducer which can be used as a transmitter that transmits an acoustic wave and an acoustic wave receiver (microphone) that receives an acoustic wave. Particularly, an ultrasonic transceiver capable of transmitting and receiving an ultrasonic wave is related. BACKGROUND

[0002] As a document that discloses a structure of a transducer, there is U.S. Patent Application Publication No. 2019 / 0110132 specification (Patent Document 1). The transducer described in Patent Document 1 includes a plurality of plates and a plurality of springs. The plurality of springs each connect two adjacent plates to each other. The plurality of springs each include a first spring arm and a second spring arm that sandwich a gap between the two adjacent plates. The first spring arm and the second spring arm each include a portion that surrounds an etched portion of the plate.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: U.S. Patent Application Publication No. 2019 / 0110132 specification SUMMARY

[0006] Problems to be Solved by the Invention

[0007] In the transducer disclosed in Patent Document 1, the plates adjacent to each other at a position between the fixed end portion and the front end portion of the plate as a beam portion are connected to each other by the springs. In the case where the adjacent beam portions are connected to each other at the position between the fixed end portion and the front end portion of the beam portion, it is difficult to make the entirety of the respective front end portions of the plurality of beam portions resonate in synchronization.

[0008] The present application was made in view of the above-described problems, and an object thereof is to provide a transducer capable of making the entirety of the respective front end portions of a plurality of beam portions resonate in synchronization.

[0009] Technical Solution for Solving the Problems

[0010] The transducer according to the present application includes a ring-shaped base portion, a first beam portion, a second beam portion, and a first connecting portion. The first beam portion has a first fixed end portion connected to the base portion, and a first front end portion located near the center of the base portion on the side opposite to the first fixed end portion, and extends from the first fixed end portion toward the first front end portion. The second beam portion is adjacent to the first beam portion in the circumferential direction of the base portion, has a second fixed end portion connected to the base portion, and a second front end portion located near the center of the base portion on the side opposite to the second fixed end portion, and extends from the second fixed end portion toward the second front end portion. The first connecting portion connects the first front end portion and the second front end portion to each other. The first connecting portion is surrounded by the partitioning slit connecting the center of the first front end portion and the center of the base portion and the center of the second front end portion, the first front end portion, and the second front end portion.

[0011] Effects of the Invention

[0012] According to the present application, it is possible to make the entire body including the respective front end portions of the plurality of beam portions vibrate in resonance in synchronization. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 is a plan view of a transducer according to an embodiment of the present application.

[0014] Figure 2 is a cross-sectional view of the transducer shown in Figure 1 , as viewed from the direction of the arrows of line II-II.

[0015] Figure 3 is a partial plan view showing III of Figure 1 in enlarged scale.

[0016] Figure 4 is a partial plan view showing a first connecting portion of a transducer according to an embodiment of the present application in enlarged scale.

[0017] Figure 5 is a partial plan view of a transducer according to a first modification of an embodiment of the present application.

[0018] Figure 6 is a plan view of a transducer according to a second modification of an embodiment of the present application.

[0019] Figure 7 is a partial cross-sectional view of the transducer shown in Figure 6 , as viewed from the direction of the arrows of line VII-VII.

[0020] Figure 8 is a plan view of a transducer according to a third modification of an embodiment of the present application.

[0021] Figure 9 is a partial cross-sectional view of the transducer shown in Figure 8A partial cross-sectional view of the transducer shown is observed.

[0022] Figure 10 A cross-sectional view schematically showing a portion of a beam portion of a transducer to which an embodiment of the present application is applied.

[0023] Figure 11 A cross-sectional view schematically showing a portion of a beam portion of a transducer to which an embodiment of the present application is applied, at the time of driving.

[0024] Figure 12 A perspective view showing a state in which a transducer to which an embodiment of the present application is applied vibrates in a fundamental vibration mode, by simulation.

[0025] Figure 13 A cross-sectional view showing a state in which a second electrode layer is provided to a piezoelectric single crystal substrate in a manufacturing method of a transducer to which an embodiment of the present application is applied.

[0026] Figure 14 A cross-sectional view showing a state in which a first support portion is provided in a manufacturing method of a transducer to which an embodiment of the present application is applied.

[0027] Figure 15 A cross-sectional view showing a state after a laminated body is joined to the first support portion in a manufacturing method of a transducer to which an embodiment of the present application is applied.

[0028] Figure 16 A cross-sectional view showing a state in which a piezoelectric body layer is formed by reducing a piezoelectric single crystal substrate in a manufacturing method of a transducer to which an embodiment of the present application is applied.

[0029] Figure 17 A cross-sectional view showing a state in which a first electrode layer is provided to the piezoelectric body layer in a manufacturing method of a transducer to which an embodiment of the present application is applied.

[0030] Figure 18 A cross-sectional view showing a state in which a groove portion and a recess portion are provided in a manufacturing method of a transducer to which an embodiment of the present application is applied.

[0031] Figure 19 A partial cross-sectional view showing a state in which a first connection electrode layer and a second connection electrode layer are provided in a manufacturing method of a transducer to which an embodiment of the present application is applied.

[0032] Figure 20 A partial plan view of a transducer to which a fourth modification of an embodiment of the present application is applied.

[0033] Figure 21 A partial plan view of a transducer to which a fifth modification of an embodiment of the present application is applied.

[0034] Figure 22 is a partial plan view of a transducer according to a sixth modification of an embodiment of the present application.

[0035] Figure 23 is a partial plan view of a transducer according to a seventh modification of an embodiment of the present application.

[0036] Figure 24 is a partial plan view of a transducer according to an eighth modification of an embodiment of the present application.

[0037] Figure 25 is a partial plan view of a transducer according to a ninth modification of an embodiment of the present application. DETAILED DESCRIPTION

[0038] Hereinafter, a transducer according to an embodiment of the present application will be described with reference to the drawings. In the following description of the embodiment, the same or corresponding portions in the drawings are denoted by the same reference numerals, and the description thereof will not be repeated. In addition, in the following description, the center of the base 110 refers to a position including the center C of the base 110 and the vicinity of the center C, which will be described later.

[0039] Figure 1 is a plan view of a transducer according to an embodiment of the present application. Figure 2 is a cross-sectional view of the transducer of Figure 1 viewed from the arrow direction of line II-II. Figure 3 is a partial plan view of the III portion of Figure 1 enlarged.

[0040] As shown in Figures 1 to 3 , a transducer 100 according to an embodiment of the present application includes a ring-shaped base 110, a first beam portion 120a, a second beam portion 120b, and a first connecting portion 130a. The transducer 100 further includes a third beam portion 120c, a fourth beam portion 120d, a second connecting portion 130b, a third connecting portion 130c, and a fourth connecting portion 130d. The plurality of beam portions of the transducer 100 according to the embodiment are each capable of flexural vibration, and can be used as an ultrasonic transducer.

[0041] When viewed from the stacking direction of the plurality of layers, which will be described later, the base 110 has a ring shape, specifically, a rectangular ring shape. In addition, the shape of the base 110 when viewed from the above stacking direction is not particularly limited as long as it is a ring shape. When viewed from the above stacking direction, the outer peripheral side surface of the base 110 can be a polygonal shape or a circular shape, and the inner peripheral side surface can be a polygonal shape or a circular shape.

[0042] As shown in Figure 1As shown, the first beam portion 120a has a first fixed end portion 121a connected to the base portion 110, and a first front end portion 122a located near the center of the base portion 110 on the side opposite the first fixed end portion 121a, the first beam portion 120a extending from the first fixed end portion 121a toward the first front end portion 122a.

[0043] The second beam portion 120b is adjacent to the first beam portion 120a in the circumferential direction of the base portion 110, has a second fixed end portion 121b connected to the base portion 110, and a second front end portion 122b located near the center of the base portion 110 on the side opposite the second fixed end portion 121b, the second beam portion 120b extending from the second fixed end portion 121b toward the second front end portion 122b.

[0044] The third beam portion 120c is adjacent to the second beam portion 120b in the circumferential direction of the base portion 110, has a third fixed end portion 121c connected to the base portion 110, and a third front end portion 122c located near the center of the base portion 110 on the side opposite the third fixed end portion 121c, the third beam portion 120c extending from the third fixed end portion 121c toward the third front end portion 122c.

[0045] The fourth beam portion 120d is adjacent to each of the third beam portion 120c and the first beam portion 120a in the circumferential direction of the base portion 110, has a fourth fixed end portion 121d connected to the base portion 110, and a fourth front end portion 122d located near the center of the base portion 110 on the side opposite the fourth fixed end portion 121d, the fourth beam portion 120d extending from the fourth fixed end portion 121d toward the fourth front end portion 122d.

[0046] The first beam portion 120a, the second beam portion 120b, the third beam portion 120c, and the fourth beam portion 120d are all located in the same plane. Alternatively, at least one of the first beam portion 120a, the second beam portion 120b, the third beam portion 120c, and the fourth beam portion 120d can be warped so as to intersect the plane. The first beam portion 120a, the second beam portion 120b, the third beam portion 120c, and the fourth beam portion 120d each extend from the annular base portion 110 toward the center of the annular base portion 110, and are adjacent to each other in the circumferential direction of the base portion 110. In the present embodiment, the first beam portion 120a, the second beam portion 120b, the third beam portion 120c, and the fourth beam portion 120d are configured to be rotationally symmetrical with respect to the center of the base portion 110.

[0047] The first connecting portion 130a connects the first front end portion 122a and the second front end portion 122b to each other. The second connecting portion 130b connects the second front end portion 122b and the third front end portion 122c to each other. The third connecting portion 130c connects the third front end portion 122c and the fourth front end portion 122d to each other. The fourth connecting portion 130d connects the fourth front end portion 122d and the first front end portion 122a to each other.

[0048] like Figure 2 As shown, the first beam 120a, the second beam 120b, the third beam 120c, and the fourth beam 120d are each piezoelectric vibrating sections comprising multiple layers 10. Furthermore, in Figure 1 The individual layers of the multiple layers 10 are not shown in the diagram. The details of the structure of the multiple layers 10 will be described later.

[0049] The first fixed end 121a, the second fixed end 121b, the third fixed end 121c, and the fourth fixed end 121d are located in the same imaginary plane. Viewed from the aforementioned stacking direction, the first fixed end 121a, the second fixed end 121b, the third fixed end 121c, and the fourth fixed end 121d are connected to the inner peripheral surface of the annular base 110. Viewed from the aforementioned stacking direction, the first fixed end 121a, the second fixed end 121b, the third fixed end 121c, and the fourth fixed end 121d are located adjacent to each other on the aforementioned inner peripheral surface. In this embodiment, since the first fixed end 121a, the second fixed end 121b, the third fixed end 121c, and the fourth fixed end 121d are respectively connected to multiple edges of the rectangular annular inner peripheral surface of the base 110, they are located at positions corresponding one-to-one with each edge of the rectangular annular inner peripheral surface of the base 110 when viewed from the aforementioned stacking direction.

[0050] In this embodiment, the first beam portion 120a, the second beam portion 120b, the third beam portion 120c, and the fourth beam portion 120d each extend along the same imaginary plane when the transducer 100 is not driven.

[0051] like Figure 1 As shown, when viewed from the aforementioned stacking direction, the first beam portion 120a, the second beam portion 120b, the third beam portion 120c, and the fourth beam portion 120d each have a small front end. Specifically, when viewed from the aforementioned stacking direction, the first beam portion 120a, the second beam portion 120b, the third beam portion 120c, and the fourth beam portion 120d each have a roughly trapezoidal shape.

[0052] In this embodiment, from the perspective of facilitating bending vibration, the lengths in the extending directions of the first beam portion 120a, the second beam portion 120b, the third beam portion 120c, and the fourth beam portion 120d are preferably at least five times the thicknesses in the aforementioned stacking directions of each of the first beam portion 120a, the second beam portion 120b, the third beam portion 120c, and the fourth beam portion 120d. Furthermore, in Figure 2 The thickness of the first beam 120a, the second beam 120b, the third beam 120c, and the fourth beam 120d is schematically shown in the figure.

[0053] like Figure 1 and Figure 3 As shown, a first slit 141a extending toward the center of the base 110 is formed between the first beam portion 120a and the second beam portion 120b. A second slit 141b extending toward the center of the base 110 is formed between the second beam portion 120b and the third beam portion 120c. A third slit 141c extending toward the center of the base 110 is formed between the third beam portion 120c and the fourth beam portion 120d. A fourth slit 141d extending toward the center of the base 110 is formed between the fourth beam portion 120d and the first beam portion 120a.

[0054] The first slit 141a is located on the two sides extending from the first fixed end 121a to the first front end 122a along the generally trapezoidal shape of the first beam portion 120a. The second slit 141b is located on the two sides extending from the second fixed end 121b to the second front end 122b along the generally trapezoidal shape of the second beam portion 120b. The third slit 141c is located on the two sides extending from the third fixed end 121c to the third front end 122c along the generally trapezoidal shape of the third beam portion 120c. The fourth slit 141d is located on the two sides extending from the fourth fixed end 121d to the fourth front end 122d along the generally trapezoidal shape of the fourth beam portion 120d. In this embodiment, when viewed from the above-mentioned stacking direction, the first slit 141a, the second slit 141b, the third slit 141c, and the fourth slit 141d extend from each of the multiple corners of the rectangular annulus of the base 110 toward the center of the base 110, and are therefore located at positions that correspond one-to-one with the corners of the rectangular annulus of the base 110.

[0055] The width of each of the first slit 141a, the second slit 141b, the third slit 141c, and the fourth slit 141d, as viewed in the stacking direction, is preferably 10 μm or less, more preferably 1 μm or less. The width of each of the first slit 141a, the second slit 141b, the third slit 141c, and the fourth slit 141d, as viewed in the stacking direction, is preferably 300% or less, more preferably 30% or less, relative to the thickness of each of the first beam portion 120a, the second beam portion 120b, the third beam portion 120c, and the fourth beam portion 120d.

[0056] The first connecting portion 130a, the second connecting portion 130b, the third connecting portion 130c, and the fourth connecting portion 130d are separated from each other by the division slit 142. The division slit 142 is composed of a first division slit 142a, a second division slit 142b, a third division slit 142c, and a fourth division slit 142d.

[0057] The first division slit 142a extends in a first direction (X-axis direction) from the first fixed end portion 121a toward the first front end portion 122a, and links the center 122ac of the first front end portion 122a and the center of the base portion 110. The second division slit 142b extends in a second direction (Y-axis direction) from the second fixed end portion 121b toward the second front end portion 122b, and links the center 122bc of the second front end portion 122b and the center of the base portion 110. The third division slit 142c extends in the first direction (X-axis direction) from the third fixed end portion 121c toward the third front end portion 122c, and links the center 122cc of the third front end portion 122c and the center of the base portion 110. The fourth division slit 142d extends in the second direction (Y-axis direction) from the fourth fixed end portion 121d toward the fourth front end portion 122d, and links the center 122dc of the fourth front end portion 122d and the center of the base portion 110.

[0058] As shown in FIG. 1, the first connecting portion 130a is surrounded by the first division slit 142a and the second division slit 142b, the first front end portion 122a, and the second front end portion 122b, the first division slit 142a and the second division slit 142b linking the center 122ac of the first front end portion 122a and the center of the base portion 110 and the center 122bc of the second front end portion 122b. The first connecting portion 130a is connected to the center 122ac of the first front end portion 122a and the center 122bc of the second front end portion 122b. Figure 1 Figure 3 As shown in FIG. 1, the first connecting portion 130a is surrounded by the first division slit 142a and the second division slit 142b, the first front end portion 122a, and the second front end portion 122b, the first division slit 142a and the second division slit 142b linking the center 122ac of the first front end portion 122a and the center of the base portion 110 and the center 122bc of the second front end portion 122b. The first connecting portion 130a is connected to the center 122ac of the first front end portion 122a and the center 122bc of the second front end portion 122b.

[0059] ​The second connecting portion 130b is surrounded by the second split slit 142b and the third split slit 142c, the second front end portion 122b, and the third front end portion 122c, wherein the second split slit 142b and the third split slit 142c join the center 122bc of the second front end portion 122b and the center of the base portion 110 and the center 122cc of the third front end portion 122c. The second connecting portion 130b is connected to the center 122bc of the second front end portion 122b and the center 122cc of the third front end portion 122c.

[0060] The third connecting portion 130c is surrounded by the third split slit 142c and the fourth split slit 142d, the third front end portion 122c, and the fourth front end portion 122d, wherein the third split slit 142c and the fourth split slit 142d join the center 122cc of the third front end portion 122c and the center of the base portion 110 and the center 122dc of the fourth front end portion 122d. The third connecting portion 130c is connected to the center 122cc of the third front end portion 122c and the center 122dc of the fourth front end portion 122d.

[0061] The fourth connecting portion 130d is surrounded by the fourth split slit 142d and the first split slit 142a, the fourth front end portion 122d, and the first front end portion 122a, wherein the fourth split slit 142d and the first split slit 142a join the center 122dc of the fourth front end portion 122d and the center of the base portion 110 and the center 122ac of the first front end portion 122a. The fourth connecting portion 130d is connected to the center 122dc of the fourth front end portion 122d and the center 122ac of the first front end portion 122a.

[0062] The first connecting portion 130a, the second connecting portion 130b, the third connecting portion 130c, and the fourth connecting portion 130d are each in a serpentine shape. Figure 4 is a partial plan view that enlargedly shows the first connecting portion of the transducer to which the embodiment of the present application relates. As shown in Figure 3 and Figure 4 As shown in

[0063] As shown in Figure 4 The first connecting portion 130a includes a plurality of long portions 131 and at least one short portion. In the present embodiment, a plurality of short portions are included as the at least one short portion. Specifically, the first connecting portion 130a includes a first short portion 132A and a second short portion 132B as the plurality of short portions.

[0064] The plurality of long portions 131 each extend in a first direction (X-axis direction) from the first fixed end portion 121a toward the first front end portion 122a. The length of each of the plurality of long portions 131 is substantially the same as that of the other.

[0065] The at least one short portion extends in a second direction (Y-axis direction) from the second fixed end portion 121b toward the second front end portion 122b, and connects end portions of certain ends in the first direction (X-axis direction) of long portions 131 adjacent to each other among the plurality of long portions 131 to each other. The width in the first direction (X-axis direction) of the at least one short portion is wider than the width in the second direction (Y-axis direction) of each of the plurality of long portions 131. However, the width in the first direction (X-axis direction) of the at least one short portion can also be equal to or smaller than the width in the second direction (Y-axis direction) of each of the plurality of long portions 131.

[0066] The long portions 131 arranged in the second direction (Y-axis direction) among the plurality of long portions 131 are alternately connected at the first end portions and the second end portions in the first direction (X-axis direction) by corresponding short portions among the plurality of short portions. Specifically, with respect to the long portion 131 connected to the center of the first front end portion 122a, the plurality of long portions 131 are arranged in parallel toward the second front end portion 122b, and the second end portions on the second division slit 142b side of the long portion 131 connected to the center of the first front end portion 122a and the long portion 131 adjacent to the long portion 131 are connected to each other by the second short portion 132B. The first end portions on the first front end portion 122a side of the long portion 131 adjacent to the long portion 131 connected to the center of the first front end portion 122a at the second end portion and the long portion 131 adjacent to the long portion 131 on the second front end portion 122b side are connected to each other by the first short portion 132A. Thus, the first short portion 132A and the second short portion 132B alternately connect the first end portions and the second end portions of the plurality of long portions 131 toward the second front end portion 122b. The second end portion of the long portion 131 opposite to the second front end portion 122b among the plurality of long portions 131 is connected to the center of the second front end portion 122b.

[0067] A plurality of first intermediate slits 143a and at least one second intermediate slit 143b are formed in the first connecting portion 130a. The plurality of first intermediate slits 143a each extend from the second division slit 142b toward the front end portion 122a of the first beam portion 120a. The at least one second intermediate slit 143b is disposed one between the first intermediate slits 143a adjacent to each other among the plurality of first intermediate slits 143a, and extends from the front end portion 122a of the first beam portion 120a toward the second division slit 142b. Specifically, the plurality of first intermediate slits 143a and the plurality of second intermediate slits 143b are provided in a manner of dividing the plurality of long portions 131 from each other. The plurality of first intermediate slits 143a extend from the second division slit 142b to a central portion in the second direction (Y-axis direction) of the first short portion 132A.

[0068] In the present embodiment, the plurality of second intermediate slits 143b are formed in the first connecting portion 130a. However, it is sufficient that at least one second intermediate slit 143b is formed in the first connecting portion 130a. The plurality of second intermediate slits 143b each are connected to the first connecting slit 140ab extending from the front end of the first slit 141a to one end in the Y-axis direction. Specifically, the plurality of second intermediate slits 143b extend from the first connecting slit 140ab to a central portion in the second direction (Y-axis direction) of the second short portion 132B.

[0069] The plurality of first intermediate slits 143a and the plurality of second intermediate slits 143b are alternately disposed one by one in the second direction (Y-axis direction). The plurality of first intermediate slits 143a and the at least one second intermediate slit 143b each are located at a position parallel to the first division slit 142a. The length La of each of the plurality of first intermediate slits 143a and the length Lb of the at least one second intermediate slit 143b are substantially the same as each other.

[0070] A first limit slit 140ba extending in the X-axis direction between the front end of the first slit 141a and the second division slit 142b is formed in the first connecting portion 130a. In the present embodiment, the first limit slit 140ba is connected to the front end of the first slit 141a.

[0071] The boundary of the first connecting portion 130a is defined by the first division slit 142a, the second division slit 142b, the first connecting slit 140ab, and the first limit slit 140ba. Specifically, the first connecting slit 140ab is located at the boundary between the first beam portion 120a and the first connecting portion 130a. The first limit slit 140ba is located at the boundary between the second beam portion 120b and the first connecting portion 130a.

[0072] As Figure 4The width of each slit is shown as Ws. The width of the long portion 131 in the second direction (Y-axis direction) is Wm. The width of each of the first short portion 132A and the second short portion 132B in the first direction (X-axis direction) is a. The length of each of the first direction (X-axis direction) and the second direction (Y-axis direction) of the first connecting portion 130a is L. For example, Wm = 10 μm, Ws = 1 μm, and a = 15 μm. It is preferable that Ws ≤ 1 μm be satisfied.

[0073] The width Wm of each of the plurality of long portions 131 in the second direction (Y-axis direction) is wider than the width Ws of the intermediate slit in the second direction (Y-axis direction) between long portions 131 adjacent to each other among the plurality of long portions 131. That is, the size of the shortest distance Wm between the first intermediate slit 143a and the second intermediate slit 143b adjacent to each other is larger than the size of the width Ws in the second direction (Y-axis direction) of each of the plurality of first intermediate slits 143a and the size of the width Ws in the (Y-axis direction) of at least one second intermediate slit 143b.

[0074] The size of the shortest distance a between the at least one second intermediate slit 143b and the second division slit 142b is larger than the size of the shortest distance Wm between the first intermediate slit 143a and the second intermediate slit 143b adjacent to each other. However, the size of the shortest distance a between the at least one second intermediate slit 143b and the second division slit 142b can also be below the size of the shortest distance Wm between the first intermediate slit 143a and the second intermediate slit 143b adjacent to each other.

[0075] If the number of turns of the serpentine shape of the first connecting portion 130a is n, the relationship of L = (Wm + Ws) x n or L = (Wm + Ws) x (n + 1) is satisfied. In addition, Figure 4 The number of turns n of the serpentine shape of the first connecting portion 130a shown is 6, and the relationship of L = (Wm + Ws) x 7 is satisfied. However, the relationship of L = (Wm + Ws) x n or L = (Wm + Ws) x (n + 1) can not necessarily be satisfied.

[0076] The first connecting portion 130a has an area of 70% or more and less than 100% in the region surrounded by the first division slit 142a, the second division slit 142b, the first front end portion 122a, and the second front end portion 122b. In addition, the first connecting portion 130a can also be less than 70% in the region surrounded by the first division slit 142a, the second division slit 142b, the first front end portion 122a, and the second front end portion 122b.

[0077] Each of the second connecting portion 130b, the third connecting portion 130c, and the fourth connecting portion 130d has the same structure as the first connecting portion 130a.

[0078] In the second connecting portion 130b, the plurality of first intermediate slits 143a each extend from the second division slit 142b toward the front end portion 122c of the third beam portion 120c. The plurality of second intermediate slits 143b each connect with the second connecting slit 140cb extending from the front end of the second slit 141b toward one end in the Y-axis direction.

[0079] In the second connecting portion 130b, the second limiting slit 140bc extending in the X-axis direction between the front end of the second slit 141b and the second division slit 142b is formed. In the present embodiment, the second limiting slit 140bc is connected with the front end of the second slit 141b.

[0080] The boundary of the second connecting portion 130b is defined by the second division slit 142b, the third division slit 142c, the second connecting slit 140cb, and the second limiting slit 140bc. Specifically, the second limiting slit 140bc is located at the boundary between the second beam portion 120b and the second connecting portion 130b. The second connecting slit 140cb is located at the boundary between the third beam portion 120c and the second connecting portion 130b.

[0081] In the region surrounded by the second division slit 142b, the third division slit 142c, the second front end portion 122b, and the third front end portion 122c, the second connecting portion 130b has an area of 90% or more and less than 100%.

[0082] In the third connecting portion 130c, the plurality of first intermediate slits 143a each extend from the fourth division slit 142d toward the front end portion 122c of the third beam portion 120c. The plurality of second intermediate slits 143b each connect with the third connecting slit 140cd extending from the front end of the third slit 141c toward the other end in the Y-axis direction.

[0083] In the third connecting portion 130c, the third limiting slit 140dc extending in the X-axis direction between the front end of the third slit 141c and the fourth division slit 142d is formed. In the present embodiment, the third limiting slit 140dc is connected with the front end of the third slit 141c.

[0084] The boundary of the third connecting portion 130c is defined by the third division slit 142c, the fourth division slit 142d, the third connecting slit 140cd, and the third limiting slit 140dc. Specifically, the third connecting slit 140cd is located at the boundary between the third beam portion 120c and the third connecting portion 130c. The third limiting slit 140dc is located at the boundary between the fourth beam portion 120d and the third connecting portion 130c.

[0085] The third connecting portion 130c has an area of 90% or more and less than 100% in a region surrounded by the third division slit 142c, the fourth division slit 142d, the third front end portion 122c, and the fourth front end portion 122d.

[0086] In the fourth connecting portion 130d, the plurality of first intermediate slits 143a each extend from the fourth division slit 142d toward the front end portion 122a of the first beam portion 120a. The plurality of second intermediate slits 143b each connect with the fourth connecting slit 140ad extending from the front end of the fourth slit 141d to the other end in the Y-axis direction.

[0087] In the fourth connecting portion 130d, a fourth limiting slit 140da extending in the X-axis direction between the front end of the fourth slit 141d and the fourth division slit 142d is formed. In the present embodiment, the fourth limiting slit 140da is connected with the front end of the fourth slit 141d.

[0088] The boundary of the fourth connecting portion 130d is defined by the third division slit 142c, the fourth division slit 142d, the fourth connecting slit 140ad, and the fourth limiting slit 140da. Specifically, the fourth limiting slit 140da is located at the boundary between the fourth beam portion 120d and the fourth connecting portion 130d. The fourth connecting slit 140ad is located at the boundary between the first beam portion 120a and the fourth connecting portion 130d.

[0089] The fourth connecting portion 130d has an area of 90% or more and less than 100% in a region surrounded by the fourth division slit 142d, the first division slit 142a, the fourth front end portion 122d, and the first front end portion 122a.

[0090] Here, a first modification of an embodiment of the present application in which the shapes of the slits are different will be described with reference to a transducer.

[0091] Figure 5 is a partial plan view of a transducer according to the first modification of the embodiment of the present application. In Figure 5 , the same parts as the transducer 100 according to the embodiment of the present application shown in Figure 4 are shown.

[0092] As shown in Figure 5 , in the transducer 100a according to the first modification of the embodiment of the present application, the connecting portions of the slits are curved. In addition, the end portions of the slits are rounded. Thus, internal stress in the first connecting portion 130a can be reduced.

[0093] Next, the plurality of layers 10 will be described. As shown in Figure 2As shown, in this embodiment, the plurality of layers 10 have a piezoelectric layer 11, a first electrode layer 12, and a second electrode layer 13.

[0094] The piezoelectric layer 11 is composed of a single-crystal piezoelectric material. The cutting orientation of the piezoelectric layer 11 is appropriately selected to ensure it exhibits desired device characteristics. In this embodiment, the piezoelectric layer 11 is formed by thinning a single-crystal substrate, specifically a rotary Y-cut substrate. The cutting orientation of the rotary Y-cut substrate is specifically 30°. The thickness of the piezoelectric layer 11 is, for example, 0.3 μm or more and 5.0 μm or less. The single-crystal piezoelectric material has a polarization axis. Details regarding the axial direction of the polarization axis will be described later.

[0095] The material constituting the piezoelectric layer 11 is appropriately selected to enable the transducer 100 to exhibit the desired device characteristics. In this embodiment, the piezoelectric layer 11 is composed of an inorganic material. Specifically, the piezoelectric layer 11 is composed of a basic niobate compound or a basic tantalate compound. In this embodiment, the alkali metal contained in the basic niobate compound or the basic tantalate compound is at least one of lithium, sodium, and potassium. In this embodiment, the piezoelectric layer 11 is composed of lithium niobate (LiNbO3) or lithium tantalate (LiTaO3).

[0096] like Figure 2 As shown, the first electrode layer 12 is disposed on one side of the piezoelectric layer 11 in the stacking direction of the plurality of layers 10. The second electrode layer 13 is disposed on the other side of the piezoelectric layer 11 in such a way that it is opposite to at least a portion of the first electrode layer 12 through the piezoelectric layer 11.

[0097] In this embodiment, a close-fitting layer (not shown) is disposed between the first electrode layer 12 and the piezoelectric layer 11, between the second electrode layer 13 and the piezoelectric layer 11, and between the second electrode layer 13 and the piezoelectric layer 11.

[0098] In this embodiment, the first electrode layer 12 and the second electrode layer 13 are each made of Pt. The first electrode layer 12 and the second electrode layer 13 may also be made of other materials such as Al. The bonding layer is made of Ti. The bonding layer may also be made of other materials such as NiCr alloy. The first electrode layer 12, the second electrode layer 13, and the bonding layer may each be an epitaxially grown film. When the piezoelectric layer 11 is made of lithium niobate (LiNbO3), from the viewpoint of suppressing the diffusion of the material constituting the bonding layer into the first electrode layer 12 or the second electrode layer 13, the bonding layer is preferably made of NiCr. This improves the reliability of the transducer 100.

[0099] In this embodiment, the thickness of the first electrode layer 12 and the second electrode layer 13 is, for example, 0.05 μm or more and 0.2 μm or less. The thickness of the bonding layer is, for example, 0.005 μm or more and 0.05 μm or less.

[0100] The plurality of layers 10 also include a support layer 14. The support layer 14 is disposed on the side of the piezoelectric layer 11 opposite to the side of the first electrode layer 12, and on the side of the second electrode layer 13 opposite to the side of the piezoelectric layer 11. The support layer 14 has a first support portion 14a and a second support portion 14b, the second support portion 14b being stacked on the side of the first support portion 14a opposite to the side of the piezoelectric layer 11. In this embodiment, the first support portion 14a is made of SiO2, and the second support portion 14b is made of single crystal Si. In this embodiment, the thickness of the support layer 14 is preferably thicker than that of the piezoelectric layer 11, considering the angle of bending vibration of the first beam portion 120a to the fourth beam portion 120d. Furthermore, the mechanism of bending vibration of the first beam portion 120a to the fourth beam portion 120d will be described later.

[0101] In addition, such as Figure 2 As shown, in this embodiment, the first connecting portion 130a to the fourth connecting portion 130d are formed by multiple layers 10 that respectively constitute the first beam portion 120a to the fourth beam portion 120d, which are continuous in an orthogonal direction orthogonal to the stacking direction. However, in this embodiment, the multiple layers 10 in the first connecting portion 130a to the fourth connecting portion 130d do not include the first electrode layer 12 and the second electrode layer 13. In addition, when the second support portion 14b is made of low-resistance Si, the second support portion 14b can function as a lower electrode layer without providing the second electrode layer 13. In this case, the multiple layers 10 in the first connecting portion 130a to the fourth connecting portion 130d include the lower electrode layer.

[0102] Furthermore, the components constituting the base 110 will be described. For example... Figure 2 As shown, in this embodiment, the base 110 includes multiple layers 10 identical to those in the first beam portions 120a to the fourth beam portions 120d. The multiple layers 10 of the base 110 are formed as a continuous structure through the multiple layers 10 in the first beam portions 120a to the fourth beam portions 120d. Specifically, the piezoelectric layer 11, the first electrode layer 12, the second electrode layer 13, and the support layer 14 constituting the base 110 are configured to be continuous with the piezoelectric layer 11, the first electrode layer 12, the second electrode layer 13, and the support layer 14 constituting the first beam portions 120a to the fourth beam portions 120d, respectively. Furthermore, the base 110 also includes a substrate layer 15, a first connecting electrode layer 20, and a second connecting electrode layer 30.

[0103] The substrate layer 15 is connected to the side of the support layer 14 opposite the piezoelectric layer 11 in the axial direction of the central axis of the ring-shaped base 110. The substrate layer 15 includes a first substrate layer 15a and a second substrate layer 15b, the second substrate layer 15b being laminated to the side of the first substrate layer 15a opposite the support layer 14 in the axial direction of the central axis. In the present embodiment, the first substrate layer 15a is composed of SiO2, and the second substrate layer 15b is composed of single-crystal Si.

[0104] As shown in FIG. 1, the first electrode layer 12 is exposed to the outside via the first connecting electrode layer 20. Specifically, the first electrode layer 12 is disposed on the side of the base 110 opposite the support layer 14. Figure 2 As shown in FIG. 1, the first connecting electrode layer 20 is electrically connected to the first electrode layer 12 via an unillustrated adhesion layer and is exposed to the outside. Specifically, the first connecting electrode layer 20 is disposed on the side of the second electrode layer 13 in the base 110 opposite the support layer 14.

[0105] The thickness of each of the first connecting electrode layer 20 and the second connecting electrode layer 30 is, for example, 0.1 μm or more and 1.0 μm or less. The thickness of the adhesion layer connected to the first connecting electrode layer 20 and the adhesion layer connected to the second connecting electrode layer 30 is, for example, 0.005 μm or more and 0.1 μm or less.

[0106] In the present embodiment, each of the first connecting electrode layer 20 and the second connecting electrode layer 30 is composed of Au. The first connecting electrode layer 20 and the second connecting electrode layer 30 can also be composed of other conductive materials such as Al. Each of the adhesion layer connected to the first connecting electrode layer 20 and the adhesion layer connected to the second connecting electrode layer 30 is composed of, for example, Ti. These adhesion layers can also be composed of NiCr.

[0107] As shown in FIG. 1, the first connecting electrode layer 20 is electrically connected to the first electrode layer 12 via an unillustrated adhesion layer and is exposed to the outside. Specifically, the first connecting electrode layer 20 is disposed on the side of the second electrode layer 13 in the base 110 opposite the support layer 14. Figure 2 As shown in FIG. 1, in the transducer 100 according to the present embodiment, an opening portion 101 is formed that opens to the side opposite the piezoelectric layer 11 in the lamination direction.

[0108] Here, the axial direction of the polarization axis of the single-crystal piezoelectric body that constitutes the piezoelectric layer 11 will be described. Preferably, the axial direction of the imaginary axis when the polarization axis of the single-crystal piezoelectric body is projected onto an imaginary plane orthogonal to the lamination direction extends in the same direction in any one of the first to fourth beam portions 120a to 120d, and the angle formed between the axial direction of the imaginary axis and the extension direction of each of the first to fourth slits 141a to 141d is not 45 degrees or 135 degrees when viewed in the lamination direction.

[0109] More specifically, in the present embodiment, more preferably, the axial direction of the imaginary axis and the extension direction of each of the first to fourth slits 141a to 141d form an angle of 0 degrees or more and 5 degrees or less, 85 degrees or more and 95 degrees or less, or 175 degrees or more and less than 180 degrees when viewed in the lamination direction.

[0110] Furthermore, more preferably, when viewed from the aforementioned stacking direction, the angle formed between the extension direction of each of the first beam portion 120a to the fourth beam portion 120d and the axial direction of the aforementioned imaginary axis when viewed from the aforementioned stacking direction is 40 degrees or more and 50 degrees or less, or 130 degrees or more and 140 degrees or less. The reasons for having suitable ranges for the angles related to the aforementioned imaginary axis will be described later.

[0111] In this embodiment, the axial direction of the aforementioned imaginary axis is oriented in a specific direction, but the axial direction of the aforementioned imaginary axis is not particularly limited.

[0112] Furthermore, in this embodiment, since the single-crystal piezoelectric material has a polarization axis, thermal stress is generated on the first beam portion 120a to the fourth beam portion 120d. Therefore, each of the first beam portion 120a to the fourth beam portion 120d may warp when viewed from an orthogonal direction orthogonal to the aforementioned stacking direction. Hereinafter, examples of warping deformation of each of the first beam portion 120a to the fourth beam portion 120d will be described. Additionally, in the following description, the second beam portion 120b and the third beam portion 120c are illustrated and shown.

[0113] Figure 6 This is a top view of a transducer according to a second variation of an embodiment of the present invention. Figure 7 From the direction of the arrow on line VII-VII Figure 6 A partial cross-sectional view of the transducer shown for observation.

[0114] like Figure 6 As shown, in the transducer 100b according to the second variation of an embodiment of the present invention, when viewed from the above-mentioned stacking direction, the axial direction of the above-mentioned imaginary axis forms an angle of approximately 45 degrees with each of the first slit 141a to the fourth slit 141d.

[0115] In this modified example, when thermal stress is applied to the first beam portion 120a to the fourth beam portion 120d, adjacent beam portions near the first connecting portion 130a to the fourth connecting portion 130d warp in different ways.

[0116] In the transducer 100b of this modified example, the aforementioned thermal stress is applied to the first beam portion 120a to the fourth beam portion 120d. As a result, as... Figure 7 As shown, when the transducer 100b is not driven, the ends of the adjacent beams near the center of the first connecting portion 130a to the fourth connecting portion 130d are located at different positions relative to each other in the aforementioned stacking direction.

[0117] Figure 8 This is a top view of a transducer according to a third variation of an embodiment of the present invention. Figure 9 From the direction of the arrow on line IX-IXFigure 8 a partial cross-sectional view of the transducer as viewed from the stacking direction.

[0118] As Figure 8 shown in FIG. 10, in the transducer 100c related to the third modification of the embodiment of the present application, the angle formed by the axis direction of the above-mentioned imaginary axis of the single-crystal piezoelectric body and each of the first to fourth slits 141a to 141d is substantially 0 degrees or substantially 90 degrees as viewed from the above-mentioned stacking direction.

[0119] In the transducer 100c related to the present modification, each of the first to fourth beam portions 120a to 120d is warped by applying a thermal stress to the first to fourth beam portions 120a to 120d. As a result, as Figure 9 shown in FIG. 10, in a state where the transducer 100c is not driven, the end portions of the first to fourth connecting portions 130a to 130d on the central side of the beam portions adjacent to each other are located at substantially the same positions in the above-mentioned stacking direction. In this way, in the present modification, even in the case where each of the first to fourth beam portions 120a to 120d is warped due to a thermal stress, it is possible to suppress breakage of the first to fourth connecting portions 130a to 130d, particularly, the first and second short portions 132A and 132B.

[0120] As described above, by comparing the transducer 100b related to the second modification of the embodiment of the present application and the transducer 100c related to the third modification of the embodiment of the present application, it is understood that the closer the angle formed by the axis direction of the above-mentioned imaginary axis and the extension direction of each of the first to fourth slits 141a to 141d is to 0 degrees or 90 degrees from the state of 45 degrees or 135 degrees as viewed from the above-mentioned stacking direction, the more it is possible to suppress the displacement difference caused by the thermal stress of the beam portions adjacent to each other from becoming large.

[0121] In addition, as Figure 9 shown in FIG. 10, in the transducer 100c related to the third modification of the embodiment of the present application, each of the beam portions adjacent to each other is inclined to a certain direction of the above-mentioned stacking direction when viewed from the side of the first to fourth slits 141a to 141d.

[0122] Each of the first to fourth beam portions 120a to 120d of the transducer 100 related to the embodiment of the present application is configured to be able to flexibly vibrate. Here, the mechanism of the flexural vibration of the first to fourth beam portions 120a to 120d will be described.

[0123] Figure 10 is a cross-sectional view schematically showing a part of a beam portion of a transducer related to the embodiment of the present application. Figure 11is a cross-sectional view schematically showing a part of a beam portion at the time of driving of a transducer to which the embodiment of the present application relates. Further, in Figure 10 and Figure 11 the first electrode layer and the second electrode layer are not illustrated.

[0124] As shown in Figure 10 and Figure 11 in the present embodiment, in the first to fourth beam portions 120a to 120d, the piezoelectric layer 11 functions as a stretchable layer that can stretch and contract in a planar direction orthogonal to the above-described stacking direction, and the layers other than the piezoelectric layer 11 function as a constraint layer. In the present embodiment, the support layer 14 mainly functions as the constraint layer. In this way, the constraint layer is stacked on the stretchable layer in a direction orthogonal to the stretching and contracting direction of the stretchable layer. Further, the first to fourth beam portions 120a to 120d can include a reverse stretchable layer instead of the constraint layer, which can contract in the planar direction when the stretchable layer stretches in the planar direction and stretch in the planar direction when the stretchable layer contracts in the planar direction.

[0125] Further, when the piezoelectric layer 11 as the stretchable layer is to stretch and contract in the above-described planar direction, the support layer 14 as the main part of the constraint layer constrains the stretching and contracting of the piezoelectric layer 11 at the interface with the piezoelectric layer 11. Furthermore, in the present embodiment, in each of the first to fourth beam portions 120a to 120d, the piezoelectric layer 11 as the stretchable layer is located on only one side of the stress neutral plane N of each of the first to fourth beam portions 120a to 120d. The center of gravity of the support layer 14 that mainly constitutes the constraint layer is located on the other side of the stress neutral plane N. Thus, as shown in Figure 10 and Figure 11 when the piezoelectric layer 11 as the stretchable layer stretches and contracts in the above-described planar direction, each of the first to fourth beam portions 120a to 120d bends in a direction orthogonal to the above-described planar direction. Further, the longer the distance between the stress neutral plane N and the piezoelectric layer 11, the greater the displacement amount of each of the first to fourth beam portions 120a to 120d when each of the first to fourth beam portions 120a to 120d bends. Furthermore, the greater the stress to which the piezoelectric layer 11 is to be subjected, the greater the above-described displacement amount. In this way, each of the first to fourth beam portions 120a to 120d performs bending vibration in the direction orthogonal to the above-described planar direction, starting from the first to fourth fixed end portions 121a to 121d.

[0126] Further, in the transducer 100 according to the embodiment, by providing the first to fourth connection portions 130a to 130d, vibration in the fundamental vibration mode is easily generated, and generation of vibration in the coupled vibration mode is suppressed. The fundamental vibration mode refers to a mode in which the phases of the first to fourth beam portions 120a to 120d coincide when each of the first to fourth beam portions 120a to 120d is bent, and the entire first to fourth beam portions 120a to 120d are displaced in one of upward and downward directions. On the other hand, the coupled vibration mode refers to a mode in which the phase of at least one of the first to fourth beam portions 120a to 120d does not coincide with the phases of the other beam portions 120 when each of the first to fourth beam portions 120a to 120d is bent.

[0127] Figure 12 is a perspective view showing a state in which the transducer according to an embodiment of the present application vibrates in the fundamental vibration mode by simulation. Specifically, in Figure 12 , a state in which the first to fourth beam portions 120a to 120d are each displaced toward the first electrode layer 12 side is shown. Further, in Figure 12 , the greater the displacement amount of each of the first to fourth beam portions 120a to 120d toward the first electrode layer 12 side, the lighter the color. Further, in Figure 12 , each layer constituting the plurality of layers 10 is not shown.

[0128] As shown in Figure 12 , for each of the first to fourth beam portions 120a to 120d, the beam portions adjacent to each other are connected to each other by the first to fourth connection portions 130a to 130d, and thus generation of the coupled vibration mode is suppressed. In this way, by connecting the first to fourth beam portions 120a to 120d to each other at the front end portions, it is possible to make it difficult for the coupled vibration mode to be generated.

[0129] Further, since each of the first to fourth connection portions 130a to 130d of the transducer 100 according to the embodiment has a serpentine shape, the first to fourth connection portions 130a to 130d function like a leaf spring when the first to fourth beam portions 120a to 120d vibrate, the first to fourth connection portions 130a to 130d connect the beam portions adjacent to each other to each other, and at the same time, the length of the first to fourth connection portions 130a to 130d as a leaf spring becomes long, and thus it is possible to suppress the connection force from becoming too strong.

[0130] The transducer 100 according to the embodiment easily generates vibration in the fundamental vibration mode, and suppresses generation of the coupled vibration mode, and thus the device characteristics are improved when used as an ultrasonic transducer, in particular. Hereinafter, the functional role of the transducer 100 according to the embodiment when used as an ultrasonic transducer will be described.

[0131] First, such as Figure 2 As shown, when the transducer 100 generates ultrasonic waves, a voltage is applied between the first connecting electrode layer 20 and the second connecting electrode layer 30. Then, a voltage is applied between the first electrode layer 12 connected to the first connecting electrode layer 20 and the second electrode layer 13 connected to the second connecting electrode layer 30. Furthermore, in each of the first beam portions 120a to the fourth beam portions 120d, a voltage is also applied between the first electrode layer 12 and the second electrode layer 13, which are opposite to each other and separated by the piezoelectric layer 11. As a result, since the piezoelectric layer 11 expands and contracts along an in-plane direction orthogonal to the aforementioned stacking direction, according to the above mechanism, each of the first beam portions 120a to the fourth beam portions 120d bends and vibrates along the aforementioned stacking direction. This applies a force to the medium surrounding the first beam portions 120a to the fourth beam portions 120d of the transducer 100, causing the medium to vibrate and thereby generating ultrasonic waves.

[0132] Furthermore, in the transducer 100 according to this embodiment, each of the first beam portion 120a to the fourth beam portion 120d has an inherent mechanical resonant frequency. Therefore, when the applied voltage is a sinusoidal voltage and the frequency of the sinusoidal voltage is close to the aforementioned resonant frequency, the displacement of each of the first beam portion 120a to the fourth beam portion 120d when bending increases.

[0133] When detecting ultrasound using transducer 100, the medium surrounding each of the first beam portion 120a to the fourth beam portion 120d vibrates due to the ultrasound. This vibration exerts a force on each of the first beam portions 120a to the fourth beam portion 120d, causing them to bend and vibrate. This bending and vibration of the first beam portions 120a to the fourth beam portion 120d applies stress to the piezoelectric layer 11. This stress induces a charge in the piezoelectric layer 11. The induced charge in the piezoelectric layer 11 generates a potential difference between the first electrode layer 12 and the second electrode layer 13, which are separated by the piezoelectric layer 11. This potential difference is detected by the first connecting electrode layer 20 connected to the first electrode layer 12 and the second connecting electrode layer 30 connected to the second electrode layer 13. Therefore, ultrasound can be detected in transducer 100.

[0134] Furthermore, when the ultrasonic wave being tested contains a large number of specific frequency components, and these frequency components are close to the aforementioned resonant frequency, the displacement during bending vibration of each of the first beam section 120a to the fourth beam section 120d increases. Because of this increased displacement, the aforementioned potential difference also increases.

[0135] Thus, in a case where the transducer 100 according to the present embodiment is used as an ultrasonic transducer, the design of the resonance frequency of the first to fourth beam portions 120a to 120d becomes important. The resonance frequency varies depending on the length of each of the first to fourth beam portions 120a to 120d in the extending direction, the thickness in the axial direction of the central axis, and the length of each of the first to fourth fixed end portions 121a to 121d as viewed from the axial direction, and the density and the elastic modulus of the material constituting the first to fourth beam portions 120a to 120d.

[0136] For example, in a case where the resonance frequency of each of the first to fourth beam portions 120a to 120d is designed to be around 40 kHz, in the transducer 100 according to the present embodiment shown in FIG. 1, the material constituting the piezoelectric layer 11 is set to lithium niobate, the thickness of the piezoelectric layer 11 is set to 1 μm, the thickness of each of the first and second electrode layers 12 and 13 is set to 0.1 μm, the thickness of the first support portion 14a is set to 0.8 μm, the thickness of the second support portion 14b is set to 1.4 μm, the shortest distance from each of the first to fourth fixed end portions 121a to 121d to each of the first to fourth front end portions 122a to 122d is set to 316 μm, and the length L of each of the first to fourth connecting portions 130a to 130d in the first direction (X-axis direction) and the second direction (Y-axis direction) is set to 77 μm. Figures 1 to 4

[0137] In addition, the transducer 100 according to the present embodiment is provided with the first to fourth connecting portions 130a to 130d having the above-described structure, whereby vibration in the fundamental vibration mode is easily generated, and the generation of the coupled vibration mode is suppressed. Thus, in a case where the transducer 100 is used as an ultrasonic transducer, even when an ultrasonic wave having the same frequency component as the resonance frequency is detected, the phases of the vibrations of the first to fourth beam portions 120a to 120d can be suppressed from being different from each other. Further, the case where the electric charges generated in the piezoelectric layer 11 of each of the first to fourth beam portions 120a to 120d due to the difference in the phases of the vibrations of the first to fourth beam portions 120a to 120d cancel each other out in the first or second electrode layer 12 or 13 is suppressed.

[0138] Thus, in the transducer 100, the device characteristics as an ultrasonic transducer are improved.

[0139] Hereinafter, a manufacturing method of the transducer 100 according to the present embodiment will be described. Figure 13 ​is a sectional view showing a state in which the second electrode layer is provided to the piezoelectric single crystal substrate in the manufacturing method of the transducer according to the embodiment of the present application. In Figures 14 to 19 and the like shown below are illustrated in the same sectional view as Figure 2 Figure 13

[0140] As shown in Figure 14 , first, an unillustrated adhesion layer is provided to the lower surface of the piezoelectric single crystal substrate 11a, and then the second electrode layer 13 is provided to the side opposite to the piezoelectric single crystal substrate 11a side of the adhesion layer. The second electrode layer 13 is formed to have a desired pattern by a lift-off method of evaporation. The second electrode layer 13 can also be formed by being laminated to the entire lower surface of the piezoelectric single crystal substrate 11a by sputtering, and then formed to have a desired pattern by an etching method. The second electrode layer 13 and the adhesion layer can be epitaxially grown.

[0141] Figure 14 is a sectional view showing a state in which the first support portion is provided in the manufacturing method of the transducer according to the embodiment of the present application. As shown in Figure 15 , the first support portion 14a is provided to the respective lower surfaces of the piezoelectric single crystal substrate 11a and the second electrode layer 13 by a chemical vapor deposition (CVD) method or a physical vapor deposition (PVD) method, or the like. After the first support portion 14a is just provided, the portion of the lower surface of the first support portion 14a located on the side opposite to the second electrode layer 13 side of the first support portion 14a is raised. Therefore, the lower surface of the first support portion 14a is reduced and planarized by chemical mechanical polishing (CMP), or the like.

[0142] Figure 15 is a sectional view showing a state after the laminate is joined to the first support portion in the manufacturing method of the transducer according to the embodiment of the present application. As shown in Figure 16 , the laminate 16 composed of the second support portion 14b and the substrate layer 15 is joined to the lower surface of the first support portion 14a by surface activation joining or atomic diffusion joining. In the present embodiment, the laminate 16 is an SOI (Silicon on Insulator) substrate. In addition, by planarizing the upper surface of the second support portion 14b in advance by CMP, or the like, the yield of the transducer 100 is improved. In addition, in the case where the second support portion 14b is composed of low-resistance Si, the second support portion 14b can function as a lower electrode layer, and in this case, it is not necessary to form the second electrode layer 13 and to perform CMP on the lower surface of the first support portion 14a.​​

[0143] Figure 15 is a cross-sectional view showing a state in which the piezoelectric single crystal substrate is thinned to form the piezoelectric layer in the manufacturing method of the transducer according to an embodiment of the present application. As shown in Figure 16 and Figure 17 , the piezoelectric single crystal substrate 11a is thinned by grinding the upper surface of the piezoelectric single crystal substrate 11a with a grinder. The upper surface of the thinned piezoelectric single crystal substrate 11a is further polished by CMP or the like, thereby shaping the piezoelectric single crystal substrate 11a into the piezoelectric layer 11.

[0144] Alternatively, a separation layer can be formed by previously implanting ions into the upper surface side of the piezoelectric single crystal substrate 11a, and the piezoelectric single crystal substrate 11a can be shaped into the piezoelectric layer 11 by separating the separation layer. Alternatively, the upper surface of the piezoelectric single crystal substrate 11a after the separation layer is separated can be further polished by CMP or the like, thereby shaping the piezoelectric single crystal substrate 11a into the piezoelectric layer 11.

[0145] Figure 17 is a cross-sectional view showing a state in which the first electrode layer is provided to the piezoelectric layer in the manufacturing method of the transducer according to an embodiment of the present application. As shown in Figure 18 , a not-shown adhesion layer is provided to the upper surface of the piezoelectric layer 11, and then the first electrode layer 12 is provided to the side opposite to the piezoelectric layer 11 side of the adhesion layer. The first electrode layer 12 is formed to have a desired pattern by a vapor deposition separation method. The first electrode layer 12 can be formed by sputtering after being laminated to the entire upper surface of the piezoelectric layer 11, and then formed to have a desired pattern by an etching method. The first electrode layer 12 and the adhesion layer can be epitaxially grown.

[0146] Figure 18 is a cross-sectional view showing a state in which the groove portion and the recessed portion are provided in the manufacturing method of the transducer according to an embodiment of the present application. As shown in Figure 1 , dry etching is performed by reactive ion etching (RIE) or the like in a region corresponding to a region inside the base portion 110 of the transducer 100 when viewed from the lamination direction, thereby forming a slit in the piezoelectric layer 11 and the first support portion 14a. The slit can also be formed by wet etching using fluoboric acid or the like. Further, the second support portion 14b exposed in the slit is etched by deep reactive ion etching (DRIE) so that the slit reaches the upper surface of the substrate layer 15. Thus, the groove portion 17 and the partitioning slit 142 in the transducer 100 shown in Figure 18 and 2 are formed. Figure 18 is a cross-sectional view showing a state in which the groove portion and the recessed portion are provided in the manufacturing method of the transducer according to an embodiment of the present application. As shown in

[0147] Furthermore, such as Figure 19 As shown, in the portion corresponding to the base 110 of the transducer 100, the piezoelectric layer 11 is etched by the aforementioned dry etching or wet etching to expose a portion of the second electrode layer 13. This forms a recess 18.

[0148] Figure 19 This is a partial cross-sectional view showing the state in which the first connecting electrode layer and the second connecting electrode layer are provided in a method for manufacturing a transducer according to an embodiment of the present invention. Furthermore, as... Figure 2 As shown, in the portion corresponding to the base 110, after each of the first electrode layer 12 and the second electrode layer 13 is provided with a close-fitting layer (not shown), a first connecting electrode layer 20 and a second connecting electrode layer 30 are provided on the upper surface of each close-fitting layer by a vapor deposition stripping method. The first connecting electrode layer 20 and the second connecting electrode layer 30 can also be formed by sputtering over the entire surface of the piezoelectric layer 11, the first electrode layer 12 and the exposed second electrode layer 13, and then etching to form the desired pattern.

[0149] Finally, after removing a portion of the second substrate layer 15b from the substrate layer 15 by DRIE, a portion of the first substrate layer 15a is removed by RIE. Thus, as... Figures 1 to 4 As shown, an opening 101 is provided, and a first beam portion 120a to a fourth beam portion 120d and a first connecting portion 130a to a fourth connecting portion 130d are formed.

[0150] Through the above processes, such as Figure 20 The transducer 100 according to one embodiment of the present invention is shown as shown.

[0151] As described above, in the transducer 100 according to the embodiment of the present application, the first connecting portion 130a connects the first front end portion 122a and the second front end portion 122b to each other. The first connecting portion 130a is surrounded by the split slits 142 of the center 122ac of the first front end portion 122a and the center of the base portion 110 and the center 122bc of the second front end portion 122b, the first front end portion 122a, and the second front end portion 122b. Thus, the entire first beam portion 120a of the first front end portion 122a including the first beam portion 120a and the entire second beam portion 120b of the second front end portion 122b including the second beam portion 120b can be vibrated in resonance in synchronization with each other. Further, instead of connecting all of the first beam portion 120a to the fourth beam portion 120d to each other, only the adjacent beam portions to each other are connected to each other, and thus the beam portions facing each other (for example, the first beam portion 120a and the third beam portion 120c) can be displaced in a manner of being separated from each other, and thus the vibration of the beam portions facing each other can be prevented from being hindered. As a result, the entire beam portions can be vibrated in resonance in synchronization with each other without hindering the vibration of the beam portions facing each other.

[0152] In the present embodiment, the first connecting portion 130a has a serpentine shape. Thus, the internal stress in the first connecting portion 130a can be relaxed. Further, by making the first connecting portion 130a have a serpentine shape, the connection of the first beam portion 120a and the second beam portion 120b can be prevented from becoming too strong, and thus the vibration of the first beam portion 120a and the second beam portion 120b can not be hindered.

[0153] In the present embodiment, the long portions 131 arranged in the second direction (Y-axis direction) among the plurality of long portions 131 are alternately connected at the first end portion and the second end portion in the first direction (X-axis direction) by the corresponding short portions 132A and 132B. Thus, the number of turns of the serpentine shape of the first connecting portion 130a is increased, and the internal stress in the first connecting portion 130a can be effectively relaxed. Further, as the number of turns of the serpentine shape of the first connecting portion 130a is increased, the connection of the first beam portion 120a and the second beam portion 120b can be effectively prevented from becoming too strong, and thus the vibration of the first beam portion 120a and the second beam portion 120b can not be further hindered.

[0154] In the present embodiment, the width Wm of each of the plurality of long portions 131 in the second direction (Y-axis direction) is wider than the width Ws of the first intermediate slits 143a and the second intermediate slits 143b between the long portions 131 adjacent to each other in the plurality of long portions 131 in the second direction (Y-axis direction). Thus, in the transmission and reception of the sound wave in the first connecting portion 130a, the amount of air (medium) that is transmitted and received by the long portions 131 is larger than the amount of air (medium) that passes through the first intermediate slits 143a and the second intermediate slits 143b, and thus a high transmission and reception efficiency can be maintained.

[0155] In the present embodiment, the width of the at least one short portion 132A, 132B in the first direction (X-axis direction) is wider than the width of each of the plurality of long portions 131 in the second direction (Y-axis direction). Thus, the short portions 132A, 132B, which are stress concentration sites in the first connecting portion 130a, can be made thick and strong, and thus breakage of the first connecting portion 130a can be suppressed.

[0156] In the present embodiment, the length of each of the plurality of long portions 131 is substantially the same as the length of the other long portions 131. Thus, unevenness in the stress distribution generated in the first connecting portion 130a can be reduced, and thus breakage of the first connecting portion 130a can be suppressed.

[0157] In the present embodiment, each of the plurality of first intermediate slits 143a and the at least one second intermediate slit 143b is located at a position parallel to the first division slit 142a. Thus, when the transducer 100 is driven, the long portions 131 adjacent to each other in the first direction (X-axis direction) can be suppressed from contacting each other.

[0158] In the present embodiment, the first connecting portion 130a has an area of 90% or more and less than 100% in the region surrounded by the division slit 142, the first front end portion 122a, and the second front end portion 122b. The transmission and reception efficiency of the sound wave in the first connecting portion 130a can be highly maintained.

[0159] In the present embodiment, the first to fourth beam portions 120a to 120d and the first to fourth connecting portions 130a to 130d are provided. Thus, the volume of the medium that can act when the transducer 100 is driven is increased, and the sound pressure that can be transmitted and received can be increased.

[0160] In the present embodiment, the plurality of layers 10 have the piezoelectric layer 11, the first electrode layer 12, and the second electrode layer 13. The piezoelectric layer 11 is composed of a single-crystal piezoelectric body. The first electrode layer 12 is disposed on one side of the piezoelectric layer 11 in the stacking direction of the plurality of layers 10. The second electrode layer 13 is disposed on the other side of the piezoelectric layer 11 in such a manner as to face at least a part of the first electrode layer 12 across the piezoelectric layer 11. Thus, the transducer 100 can be driven by a piezoelectric effect. In addition, the transducer 100 can be a capacitively driven transducer.

[0161] In the present embodiment, the axis direction of the imaginary axis when the polarization axis of the single-crystal piezoelectric body is projected onto an imaginary plane orthogonal to the above-described stacking direction is extended in the same direction in either one of the first beam portion 120a and the second beam portion 120b, and intersects the extending direction of each of the first beam portion 120a and the second beam portion 120b when viewed from the above-described stacking direction. Thus, in the transducer 100 in which the piezoelectric layer 11 is composed of a single-crystal piezoelectric body having a polarization axis, even if it is assumed that thermal stress is generated in each of the first beam portion 120a and the second beam portion 120b, it is possible to reduce unevenness in the stress distribution generated in the first connecting portion 130a, thereby suppressing breakage of the first connecting portion 130a.

[0162] In the present embodiment, the angle between the extending direction of each of the first beam portion 120a and the second beam portion 120b and the axis direction of the above-described imaginary axis is 40 degrees or more and 50 degrees or less, or 130 degrees or more and 140 degrees or less when viewed from the above-described stacking direction. Thus, even if it is assumed that thermal stress is generated in the first beam portion 120a and the second beam portion 120b, since each of the first beam portion 120a and the second beam portion 120b has substantially the same stress distribution in the extending direction, the warping manner of each of the first beam portion 120a and the second beam portion 120b is also substantially the same. Furthermore, it is possible to suppress a decrease in the device characteristics of the transducer 100.

[0163] In the present embodiment, the piezoelectric layer 11 is composed of lithium niobate (LiNbO3) or lithium tantalate (LiTaO3). Thus, it is possible to improve the piezoelectric characteristics of the piezoelectric layer 11, and therefore it is possible to improve the device characteristics of the transducer 100.

[0164] Hereinafter, a modified example in which only the structure of the connecting portion is different from the transducer 100 according to the embodiment of the present application will be described. In addition, the same structures as those of the transducer 100 according to the embodiment of the present application will not be described again.

[0165] Figure 20 is a partial plan view of a transducer according to a fourth modified example of the embodiment of the present application. In Figure 3 , the same portions as those of Figure 20 are illustrated in an enlarged manner.

[0166] As Figure 21 shown in FIG. 10, in the transducer 100d related to the fourth modification of the embodiment of the present application, the number n of turns of the serpentine shape of each of the first to fourth connection portions 130a to 130d is five.

[0167] The first limiting slit 140ba is connected to the front end of the second division slit 142b. The second limiting slit 140bc is connected to the front end of the second division slit 142b. The third limiting slit 140dc is connected to the front end of the fourth division slit 142d. The fourth limiting slit 140da is connected to the front end of the fourth division slit 142d.

[0168] The first connection portion 130a is connected to the center 122ac of the first front end portion 122a and the end 122ba of the second front end portion 122b close to the first beam portion 120a. The second connection portion 130b is connected to the end 122bc of the second front end portion 122b close to the third beam portion 120c and the center 122cc of the third front end portion 122c. The third connection portion 130c is connected to the center 122cc of the third front end portion 122c and the end 122dc of the fourth front end portion 122d close to the third beam portion 120c. The fourth connection portion 130d is connected to the end 122da of the fourth front end portion 122d close to the first beam portion 120a and the center 122ac of the first front end portion 122a.

[0169] Figure 21 is a partial plan view of a transducer related to a fifth modification of the embodiment of the present application. In Figure 3 , the same parts as Figure 21 are illustrated in an enlarged manner.

[0170] As Figure 22 shown in FIG. 10, in the transducer 100d related to the fourth modification of the embodiment of the present application, the number n of turns of the serpentine shape of each of the first to fourth connection portions 130a to 130d is five.

[0171] In the first connection portion 130a, a first curved slit 144ab is formed, which extends from the other end of the first division slit 142a in the Y-axis direction on the first beam portion 120a side with respect to the first connection slit 140ab. In addition, a first extension slit 144ba is formed, which extends from the other end of the second division slit 142b in the X-axis direction on the second beam portion 120b side with respect to the first limiting slit 140ba.

[0172] The first additional connection portion 133a extends to the other end in the Y-axis direction between the first connection slit 140ab and the first curved slit 144ab. The first connection portion 130a extends to the other end in the X-axis direction between the first defined slit 140ba and the first extension slit 144ba. Thus, the first connection portion 130a is connected to the end 122ab of the first front end portion 122a close to the second beam portion 120b and the end 122ba of the second front end portion 122b close to the first beam portion 120a.

[0173] The second connection portion 130b includes a second additional connection portion 133b extending in the Y-axis direction at a connection position with the third front end portion 122c of the third beam portion 120c.

[0174] The second curved slit 144cb is formed in the second connection portion 130b and extends to the other end in the Y-axis direction from the third division slit 142c on the third beam portion 120c side with respect to the second connection slit 140cb. In addition, the second extension slit 144bc is formed and extends to the one end in the X-axis direction from the second division slit 142b on the second beam portion 120b side with respect to the second defined slit 140bc.

[0175] The second additional connection portion 133b extends to the other end in the Y-axis direction between the second connection slit 140cb and the second curved slit 144cb. The second connection portion 130b extends to the one end in the X-axis direction between the second defined slit 140bc and the second extension slit 144bc. Thus, the second connection portion 130b is connected to the end 122bc of the second front end portion 122b close to the third beam portion 120c and the end 122cb of the third front end portion 122c close to the second beam portion 120b.

[0176] The third connection portion 130c includes a third additional connection portion 133c extending in the Y-axis direction at a connection position with the third front end portion 122c of the third beam portion 120c.

[0177] The third curved slit 144cd is formed in the third connection portion 130c and extends to the one end in the Y-axis direction from the third division slit 142c on the third beam portion 120c side with respect to the third connection slit 140cd. In addition, the third extension slit 144dc is formed and extends to the one end in the X-axis direction from the fourth division slit 142d on the fourth beam portion 120d side with respect to the third defined slit 140dc.

[0178] The third additional connection portion 133c extends toward one end in the Y-axis direction between the third connection slit 140cd and the third curved slit 144cd. The third connection portion 130c extends toward one end in the X-axis direction between the third defined slit 140dc and the third extended slit 144dc. Thus, the third connection portion 130c is connected to the end 122cd of the third front end portion 122c close to the fourth beam portion 120d and the end 122dc of the fourth front end portion 122d close to the third beam portion 120c.

[0179] The fourth connection portion 130d includes a fourth additional connection portion 133d extending in the Y-axis direction at a position connected to the first front end portion 122a of the first beam portion 120a.

[0180] The fourth curved slit 144ad is formed in the fourth connection portion 130d and extends toward one end in the Y-axis direction from the first divided slit 142a on the first beam portion 120a side with respect to the fourth connection slit 140ad. Further, the fourth extended slit 144da is formed and extends toward the other end in the X-axis direction from the fourth divided slit 142d on the fourth beam portion 120d side with respect to the fourth defined slit 140da.

[0181] The fourth additional connection portion 133d extends toward one end in the Y-axis direction between the fourth connection slit 140ad and the fourth curved slit 144ad. The fourth connection portion 130d extends toward the other end in the X-axis direction between the fourth defined slit 140da and the fourth extended slit 144da. Thus, the fourth connection portion 130d is connected to the end 122da of the fourth front end portion 122d close to the first beam portion 120a and the end 122ad of the first front end portion 122a close to the fourth beam portion 120d.

[0182] In the present modification example, by connecting the ends of the front end portions of the first to fourth beam portions 120a to 120d to the first to fourth connection portions 130a to 130d, respectively, the balance of the vibrations of the first to fourth beam portions 120a to 120d can be made good, and by providing the first to fourth additional connection portions 133a to 133d, the stress distribution in the first to fourth connection portions 130a to 130d can be made uniform.

[0183] Figure 22 A sixth modification example of the embodiment of the present application relates to a partial plan view of a transducer. In Figure 3 the same parts as Figure 22 are illustrated in an enlarged manner. In addition, in the description of the present modification example, the same structures as the transducer 100e relating to the fifth modification example of the embodiment of the present application are not described again.

[0184] AsFigure 23 As shown, in the transducer 100f related to the sixth modification of the embodiment of the present application, the first connecting portion 130a includes a first additional connecting portion 133a extending in the Y-axis direction and turning back at the connecting position with the first front end portion 122a of the first beam portion 120a.

[0185] The first additional bending slit 145ab is formed in the first connecting portion 130a, and extends from the first slit 141a toward one end in the Y-axis direction on the first beam portion 120a side with respect to the first bending slit 144ab. In addition, the first additional extension slit 145ba is formed, and extends from the first slit 141a toward the other end in the X-axis direction on the second beam portion 120b side with respect to the first extension slit 144ba.

[0186] The first additional connecting portion 133a extends toward one end in the Y-axis direction between the first bending slit 144ab and the first additional bending slit 145ab. The first connecting portion 130a extends toward the other end in the X-axis direction between the first extension slit 144ba and the first additional extension slit 145ba. Thus, the first connecting portion 130a is connected with the center 122ac of the first front end portion 122a and the center 122bc of the second front end portion 122b.

[0187] The second connecting portion 130b includes a second additional connecting portion 133b extending in the Y-axis direction and turning back at the connecting position with the third front end portion 122c of the third beam portion 120c.

[0188] The second additional bending slit 145cb is formed in the second connecting portion 130b, and extends from the second slit 141b toward one end in the Y-axis direction on the third beam portion 120c side with respect to the second bending slit 144cb. In addition, the second additional extension slit 145bc is formed, and extends from the second slit 141b toward the other end in the X-axis direction on the second beam portion 120b side with respect to the second extension slit 144bc.

[0189] The second additional connecting portion 133b extends toward one end in the Y-axis direction between the second bending slit 144cb and the second additional bending slit 145cb. The second connecting portion 130b extends toward the other end in the X-axis direction between the second extension slit 144bc and the second additional extension slit 145bc. Thus, the second connecting portion 130b is connected with the center 122bc of the second front end portion 122b and the center 122cc of the third front end portion 122c.

[0190] The third connecting portion 130c includes a third additional connecting portion 133c extending in the Y-axis direction and turning back at the connecting position with the third front end portion 122c of the third beam portion 120c.

[0191] A third additional bending slit 145cd is formed in the third connecting portion 130c, and extends from the third slit 141c to the other end in the Y-axis direction on the third beam portion 120c side with respect to the third bending slit 144cd. In addition, a third additional extension slit 145dc is formed, and extends from the third slit 141c to the other end in the X-axis direction on the fourth beam portion 120d side with respect to the third extension slit 144dc.

[0192] The third additional connecting portion 133c extends to the other end in the Y-axis direction between the third bending slit 144cd and the third additional bending slit 145cd. The third connecting portion 130c extends to the other end in the X-axis direction between the third extension slit 144dc and the third additional extension slit 145dc. Thus, the third connecting portion 130c is connected to the center 122cc of the third front end portion 122c and the center 122dc of the fourth front end portion 122d.

[0193] The fourth connecting portion 130d includes a fourth additional connecting portion 133d that extends in the Y-axis direction and is folded back at a position connected to the first front end portion 122a of the first beam portion 120a.

[0194] A fourth additional bending slit 145ad is formed in the fourth connecting portion 130d, and extends from the first slit 141a to the other end in the Y-axis direction on the first beam portion 120a side with respect to the fourth bending slit 144ad. In addition, a fourth additional extension slit 145da is formed, and extends from the first slit 141a to the side in the X-axis direction on the fourth beam portion 120d side with respect to the fourth extension slit 144da.

[0195] The fourth additional connecting portion 133d extends to the other end in the Y-axis direction between the fourth bending slit 144ad and the fourth additional bending slit 145ad. The fourth connecting portion 130d extends to the end in the X-axis direction between the fourth extension slit 144da and the fourth additional extension slit 145da. Thus, the fourth connecting portion 130d is connected to the center 122dc of the fourth front end portion 122d and the center 122ac of the first front end portion 122a.

[0196] In the present modified example, by connecting the center of the front end portion of each of the first to fourth beam portions 120a to 120d to the first to fourth connecting portions 130a to 130d, the balance of the vibration of the first to fourth beam portions 120a to 120d can be made good, and by folding back the first to fourth additional connecting portions 133a to 133d, the stress distribution in the first to fourth connecting portions 130a to 130d can be effectively homogenized.

[0197] Figure 23 A partial plan view of a transducer according to a seventh modification of an embodiment of the present application is shown in FIG. 17. In FIG. 17, the same parts as those of the transducer 100e shown in FIG. 16 are not enlarged. Figure 3 Figure 23 In the seventh modification of the embodiment of the present application, the same parts as those of the transducer 100e shown in FIG. 16 are not enlarged.

[0198] As shown in FIG. 17, in the transducer 100g according to the seventh modification of the embodiment of the present application, the first connecting portion 130a is connected to a position shifted by a certain distance from the center 122ac of the first front end portion 122a toward the other end in the Y-axis direction and a position shifted by the certain distance from the center 122bc of the second front end portion 122b toward the other end in the X-axis direction. Figure 24 The second connecting portion 130b is connected to a position shifted by the certain distance from the center 122bc of the second front end portion 122b toward the one end in the X-axis direction and a position shifted by the certain distance from the center 122cc of the third front end portion 122c toward the other end in the Y-axis direction.

[0199] The third connecting portion 130c is connected to a position shifted by the certain distance from the center 122cc of the third front end portion 122c toward the one end in the Y-axis direction and a position shifted by the certain distance from the center 122dc of the fourth front end portion 122d toward the one end in the X-axis direction.

[0200] The fourth connecting portion 130d is connected to a position shifted by the certain distance from the center 122dc of the fourth front end portion 122d toward the other end in the X-axis direction and a position shifted by the certain distance from the center 122ac of the first front end portion 122a toward the one end in the Y-axis direction.

[0201] In the seventh modification of the embodiment of the present application, the connecting positions and the connecting angles of the first to fourth beam portions 120a to 120d and the first to fourth connecting portions 130a to 130d are made uniform, the balance of the vibrations of the first to fourth beam portions 120a to 120d is made good, and the stress distribution in the first to fourth connecting portions 130a to 130d is effectively made uniform.

[0202]

[0203] A partial plan view of a transducer according to an eighth modification of an embodiment of the present application is shown in FIG. 18. In FIG. 18, the same parts as those of the transducer 100e shown in FIG. 16 are not enlarged. Figure 24 Figure 3 In the eighth modification of the embodiment of the present application, the same parts as those of the transducer 100e shown in FIG. 16 are not enlarged. Figure 24 As shown in FIG. 18, in the transducer 100h according to the eighth modification of the embodiment of the present application, the first connecting portion 130a is connected to a position shifted by a certain distance from the center 122ac of the first front end portion 122a toward the one end in the Y-axis direction and a position shifted by the certain distance from the center 122bc of the second front end portion 122b toward the one end in the X-axis direction.

[0204] Figure 25 ​​​As shown, in the transducer 100h according to the eighth variation of an embodiment of the present invention, the first connecting portions 130a to the fourth connecting portions 130d are symmetrically arranged with respect to the center point C of the base 110. In each of the second connecting portions 130b and the fourth connecting portions 130d, a plurality of first intermediate slits 143d and a plurality of second intermediate slits 143e each extend in the Y-axis direction.

[0205] Figure 25 This is a partial top view of a transducer according to a ninth variation of an embodiment of the present invention. Figure 3 In the middle, will be with Figure 25 Enlarged map of the same parts.

[0206] like ​ As shown, in the transducer 100i according to the ninth variation of an embodiment of the present invention, the first connecting portions 130a to the fourth connecting portions 130d are symmetrically arranged with respect to the center point C of the base 110. In each of the first connecting portions 130a and the third connecting portion 130c, a plurality of first intermediate slits 143f and a plurality of second intermediate slits 143g each extend in a direction at 45° with respect to the X-axis direction. In each of the second connecting portions 130b and the fourth connecting portion 130d, a plurality of first intermediate slits 143h and a plurality of second intermediate slits 143i each extend in a direction at 135° with respect to the X-axis direction.

[0207] In the description of the above embodiments, the combinable structures can also be combined with each other.

[0208] The embodiments disclosed herein should be considered illustrative rather than restrictive in all respects. The scope of the invention is set forth not by the foregoing description but by the claims, which are intended to encompass all modifications within the meaning and scope of the claims.

[0209] Explanation of reference numerals in the attached figures

[0210] 10 layers; 11 piezoelectric layer; 11a single crystal substrate; 12 first electrode layer; 13 second electrode layer; 14 support layer; 14a first support portion; 14b second support portion; 15 substrate layer; 15a first substrate layer; 15b second substrate layer; 16 laminate; 17 groove portion; 18 recess portion; 20 first connecting electrode layer; 30 second connecting electrode layer; 100, 100a, 100b, 100c, 100d, 100e, 100f, 100g, 100h, 100i transducer; 101 opening portion; 110 base portion; 120a first beam portion; 120b second beam portion; 120c third beam portion; 120d fourth beam portion; 121a first fixed end portion; 121b second fixed end portion; 121c third fixed end portion; 121d fourth fixed end portion; 122a first front end portion; 122ab, 122ad, 122ba, 122bc, 122cb, 122cd, 122da, 122dc end, 122b second front end portion; 122ac, 122bc, 122cc, 122dc center; 122c third front end portion; 122d fourth front end portion; 130a first connecting portion; 130b second connecting portion; 130c third connecting portion; 130d fourth connecting portion; 131 long portion; 132A first short portion; 132B second short portion; 133a first additional connecting portion; 133b second additional connecting portion; 133c third additional connecting portion; 133d fourth additional connecting portion; 140ab first connecting slit; 140ad fourth connecting slit; 140ba first limiting slit; 140bc second limiting slit; 140cb second connecting slit; 140cd third connecting slit; 140da fourth limiting slit; 140dc third limiting slit; 141a first slit; 141b second slit; 141c third slit; 141d fourth slit; 142 division slit; 142a first division slit; 142b second division slit; 142c third division slit; 142d fourth division slit; 143a, 143d, 143f, 143h first intermediate slit; 143b, 143e, 143g, 143i second intermediate slit; 144ba first extension slit; 144bc second extension slit; 144da fourth extension slit; 144dc third extension slit; 145ba first additional extension slit; 145bc second additional extension slit; 145da fourth additional extension slit; 145dc third additional extension slit; 144ab first curved slit; 144ad fourth curved slit; 144cb second curved slit; 144cd third curved slit; 145ab first additional curved slit; 145ad fourth additional curved slit; 145cb second additional curved slit; 145cd third additional curved slit.

Claims

1. A transducer comprising: a base portion in a ring shape; a first beam portion having a first fixed end portion connected to the base portion, and a first front end portion located near a center of the base portion on a side opposite to the first fixed end portion, and extending from the first fixed end portion toward the first front end portion; a second beam portion adjacent to the first beam portion in a circumferential direction of the base portion, having a second fixed end portion connected to the base portion, and a second front end portion located near the center of the base portion on a side opposite to the second fixed end portion, and extending from the second fixed end portion toward the second front end portion; and a first connecting portion connecting the first front end portion and the second front end portion to each other, the first connecting portion being surrounded by a split slit joining the center of the first front end portion and the center of the base portion and the center of the second front end portion, the first front end portion, and the second front end portion, the first connecting portion being in a serpentine shape.

3. The transducer according to claim 1 or 2, wherein the first connecting portion includes: a plurality of long portions extending in a first direction from the first fixed end portion toward the first front end portion; and at least one short portion extending in a second direction from the second fixed end portion toward the second front end portion, connecting end portions of one ends in the first direction of long portions adjacent to each other among the plurality of long portions to each other.

4. The transducer according to claim 3, wherein the first connecting portion includes a plurality of short portions as the at least one short portion, long portions arranged in the second direction among the plurality of long portions are alternately connected at first and second end portions in the first direction by corresponding short portions among the plurality of short portions, a width in the second direction of each of the plurality of long portions is wider than a width in the second direction of an intermediate slit between long portions adjacent to each other among the plurality of long portions, a width in the first direction of the at least one short portion is wider than the width in the second direction of each of the plurality of long portions, lengths of each of the plurality of long portions are the same as each other.

8. The transducer according to claim 1 or 2, wherein the split slit includes: a first split slit joining the center of the first front end portion and the center of the base portion, extending in a first direction from the first fixed end portion toward the first front end portion; and a second split slit joining the center of the second front end portion and the center of the base portion, extending in a second direction from the second fixed end portion toward the second front end portion, the first connecting portion is formed with: a plurality of first intermediate slits extending from the second split slit toward the first front end portion of the first beam portion; and at least one second intermediate slit configured one between first intermediate slits adjacent to each other among the plurality of first intermediate slits, extending from a front end portion side of the first beam portion toward the second split slit.

9. The transducer according to claim 8, wherein in the first connecting portion is formed with a plurality of second intermediate slits as the at least one second intermediate slit, ​ ​ 2. The transducer of claim 1, wherein, ​ ​ ​ ​ ​ ​ ​ ​ 5. The transducer of claim 4, wherein, ​ 6. The transducer of claim 5, wherein, ​ 7. The transducer of claim 6, wherein, ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The plurality of first intermediate slits and the plurality of second intermediate slits are alternately arranged one by one in the second direction.

10. The transducer of claim 9, wherein, The plurality of first intermediate slits and the at least one second intermediate slit are each located in parallel with the first division slit.

11. The transducer of claim 10, wherein, The size of the shortest distance between first and second intermediate slits adjacent to each other is greater than the size of the width in the second direction of each of the plurality of first intermediate slits and the size of the width in the second direction of the at least one second intermediate slit.

12. The transducer of claim 11, wherein, The size of the shortest distance between the at least one second intermediate slit and the second division slit is greater than the size of the shortest distance between first and second intermediate slits adjacent to each other.

13. The transducer of claim 12, wherein, The length of each of the plurality of first intermediate slits and the at least one second intermediate slit is the same as each other.

14. The transducer of claim 1 or 2, wherein, The first connecting portion has an area of 70% or more and less than 100% in the area surrounded by the division slit, the first front end portion, and the second front end portion.

15. The transducer of claim 1 or 2, wherein, The first connecting portion is connected to the center of the first front end portion and the center of the second front end portion.

16. The transducer of claim 1 or 2, wherein, The first connecting portion is connected to the center of the first front end portion and the end of the second front end portion near the first beam portion.

17. The transducer of claim 1 or 2, wherein, The first connecting portion is connected to the end of the first front end portion near the second beam portion and the end of the second front end portion near the first beam portion.

18. The transducer according to claim 1 or 2, further comprising: a third beam portion adjacent to the second beam portion in the circumferential direction of the base portion, having a third fixed end portion connected to the base portion, and a third front end portion located near the center of the base portion on the side opposite to the third fixed end portion, and extending from the third fixed end portion toward the third front end portion; a fourth beam portion adjacent to each of the third beam portion and the first beam portion in the circumferential direction of the base portion, having a fourth fixed end portion connected to the base portion, and a fourth front end portion located near the center of the base portion on the side opposite to the fourth fixed end portion, and extending from the fourth fixed end portion toward the fourth front end portion; a second connecting portion connecting the second front end portion and the third front end portion to each other; a third connecting portion connecting the third front end portion and the fourth front end portion to each other; and a fourth connecting portion connecting the fourth front end portion and the first front end portion to each other. The second connecting portion is surrounded by the division slit connecting the center of the second front end portion and the center of the base portion and the center of the third front end portion, the second front end portion, the third front end portion, The third connecting portion is surrounded by the division slit connecting the center of the third front end portion and the center of the base portion and the center of the fourth front end portion, the third front end portion, the fourth front end portion, The fourth connecting portion is surrounded by the division slit connecting the center of the fourth front end portion and the center of the base portion and the center of the first front end portion, the fourth front end portion, the first front end portion.

19. The transducer according to claim 1 or 2, wherein ​ The first beam portion and the second beam portion each have: a piezoelectric layer composed of a single-crystal piezoelectric body; a first electrode layer disposed on one side of the piezoelectric layer; and a second electrode layer disposed on the other side of the piezoelectric layer so as to oppose at least a portion of the first electrode layer across the piezoelectric layer.

20. The transducer of claim 19, wherein, An axis direction of an imaginary axis when a polarization axis of the single-crystal piezoelectric body is projected onto an imaginary plane orthogonal to a stacking direction of the piezoelectric layer, the first electrode layer, and the second electrode layer, is extended in the same direction in either of the first beam portion and the second beam portion, and intersects the extension direction of each of the first beam portion and the second beam portion when viewed from the stacking direction.

21. The transducer of claim 20, wherein, An angle formed between the axis direction of the imaginary axis and the extension direction of each of the first beam portion and the second beam portion when viewed from the stacking direction is 40 degrees or more and 50 degrees or less, or 130 degrees or more and 140 degrees or less.

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