Ultrasonic imaging device

Abstract

The invention provides an ultrasonic imaging apparatus capable of simply discharging fine bubbles attached to the periphery of a wafer mounted on a sample stage. The ultrasonic imaging device (1) irradiates ultrasonic waves on a wafer (2), acquires transmitted waves of the ultrasonic waves and images the transmitted waves, and is provided with a sample stage (20) for fixing the wafer (2) in water (W), the sample stage (20) is provided with an opening (21), a gripping member for gripping the wafer (2) is arranged at the edge of the opening (21), the opening (21) is configured to be larger than the wafer (2), and the wafer (2) is gripped by the gripping member, so that the wafer (2) is imaged by the gripping member. Therefore, a bubble discharging part, namely a gap (S), is formed between the outer peripheral part of the wafer (2) and the edge part of the opening part (21).

Description

Technical Field

[0001] The present invention relates to an ultrasonic imaging device. Background Art

[0002] Since ultrasonic waves have the property of being difficult to transmit in gases, in ultrasonic imaging devices, water is generally used as a medium for ultrasonic wave transmission, and the subject and the ultrasonic probe are immersed in water for examination. At this time, if air bubbles adhere to the subject, there is a problem that it becomes difficult to examine the inside of the subject at the air bubble adhesion part. In addition, when air bubbles are confirmed based on the examination results after ultrasonic examination, there is a problem that re-examination needs to be performed after removing the air bubbles. To solve these problems, the following inventions have been proposed.

[0003] For example, the ultrasonic inspection device shown in Patent Document 1 has: a water tank that houses water; a specimen stage that is disposed in the water tank and mounts the subject; a first ultrasonic probe that is disposed opposite to each other in the vertical direction and irradiates ultrasonic waves toward the subject; and a second ultrasonic probe that receives the ultrasonic waves that have passed through the subject, and a hydrophilic film is formed on the lower surface side of the specimen stage. And, a water ejection part for ejecting water is provided on the lower surface side of the said specimen stage.

[0004] In addition, the ultrasonic inspection device shown in Patent Document 2 has: an ultrasonic probe that irradiates and receives ultrasonic waves; a specimen stage that mounts an inspection object (subject) for performing inspection based on ultrasonic waves; a water tank that stores a liquid medium (water) for immersing the specimen stage; and a nozzle that discharges the liquid medium to the specimen stage, the ultrasonic probe moves within the inspection range, and the nozzle follows the movement of the ultrasonic probe.

[0005] Prior Art Documents

[0006] Patent Documents

[0007] Patent Document 1: Japanese Patent Laid-Open No. 2014-215154

[0008] Patent Document 2: Japanese Patent Laid-Open No. 2019-219234 Summary of the Invention

[0009] Problems to be Solved by the Invention

[0010] However, the ultrasonic inspection devices described in Patent Documents 1 and 2 remove air bubbles by ejecting a liquid from the lower surface of the specimen stage on which the subject is placed. In this method, it is difficult to remove fine air bubbles adhering to the periphery of the subject when the subject is placed on the specimen stage.

[0011] The present invention is used to solve the above-mentioned conventional problems, and its object is to provide an ultrasonic imaging device capable of simply discharging minute bubbles adhering to the periphery of a subject mounted on a specimen stage.

[0012] Means for Solving the Problem

[0013] The present invention is an ultrasonic imaging device that irradiates ultrasonic waves to a subject, obtains a transmitted wave thereof, and forms an image. The ultrasonic imaging device is characterized by including a specimen stage for fixing the subject in water, the specimen stage having an opening, a holding member for holding the subject provided at an edge portion of the opening, the opening being configured to be larger than the subject, and a bubble discharging portion being formed between an outer peripheral portion of the subject and an edge portion of the opening by holding the subject with the holding member.

[0014] Effect of the Invention

[0015] According to the present invention, it is possible to provide an ultrasonic imaging device capable of simply discharging minute bubbles adhering to the periphery of a subject mounted on a specimen stage. Description of the Drawings

[0016] Figure 1 It is a structural diagram of an ultrasonic imaging device showing an embodiment of the present invention.

[0017] Figure 2 It is a perspective view of an ultrasonic imaging device showing an embodiment of the present invention.

[0018] Figure 3 It is a perspective view showing a state in which a specimen stage is mounted on a specimen stage holding portion.

[0019] Figure 4 It shows a state Figure 3 in which a pressing member is removed from a specimen stage holding portion.

[0020] Figure 5 It is Figure 4 an enlarged view of a carrier member.

[0021] Figure 6 It is a perspective view showing a state in which a specimen stage is held by a specimen stage holding portion.

[0022] Figure 7 It is a plan view showing a state in which a specimen stage on which a wafer is mounted is mounted on a specimen stage holding portion.

[0023] Figure 8 It is a plan view showing a state in the middle of mounting a specimen stage holding a wafer on a specimen stage holding portion.

[0024] Reference Signs

[0025] 1: Ultrasonic imaging device; 2: Wafer (specimen); 10: Water tank; 20: Specimen stage; 21: Opening; 30: Specimen stage holding part; 40: First ultrasonic probe; 50: Second ultrasonic probe; 71: Carrying member; 72: Pressing member; S: Gap (bubble discharge part); W: Water. Detailed implementation mode

[0026] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the following embodiments, and various modification examples and application examples are also included within the scope of the technical concept of the present invention.

[0027] Figure 1 It is a structural diagram of an ultrasonic imaging device showing an embodiment of the present invention. Figure 2 It is a perspective view of an ultrasonic imaging device showing an embodiment of the present invention.

[0028] As Figure 1 shown, the ultrasonic imaging device 1 measures the inside of the specimen in a non-destructive manner by ultrasonic waves in water W as an ultrasonic wave transmission medium, displays a detection image of the specimen, or determines whether internal defects are qualified.

[0029] The ultrasonic imaging device 1 is configured to include: a specimen stage 20 disposed in the water tank 10 and on which a wafer 2 (specimen) is placed; a first ultrasonic probe 40 disposed above the wafer 2; and a second ultrasonic probe 50 disposed below the wafer 2. The first ultrasonic probe 40 and the second ultrasonic probe 50 are disposed at positions opposed to each other in the vertical direction (Z direction). In addition, the wafer 2 is, for example, a circular thin plate-shaped wafer made of a material that becomes a semiconductor integrated circuit.

[0030] The first ultrasonic probe 40 is a probe (irradiation probe) that irradiates ultrasonic waves toward the wafer 2. The second ultrasonic probe 50 receives ultrasonic waves that have passed through the wafer 2 (reception probe). In addition, contrary to this embodiment, the second ultrasonic probe 50 may be used as the irradiation probe and the first ultrasonic probe 40 may be used as the reception probe.

[0031] The specimen stage 20 is held by the specimen stage holding part 30 in the water tank 10 and is horizontally disposed. In addition, the water in the water tank 10 is not limited to pure water, and tap water may also be used, and there is no particular limitation. In addition, the shape of the water tank 10 is not limited to a rectangular box shape as in this embodiment, and may be, for example, a bottomed cylindrical shape. In addition, the structure and function of the specimen stage 20 will be described in detail later.

[0032] The first ultrasonic probe 40 and the second ultrasonic probe 50 are configured to be arranged vertically with the object to be inspected, i.e., the wafer 2, sandwiched therebetween, and can be moved by an X-axis scanning unit 61, a Y-axis scanning unit 62 (refer to Figure 2 ) and a Z-axis scanning unit 63 which are connected to a driving device (not shown).

[0033] As Figure 2 shown, the X-axis scanning unit 61 is provided above the water tank 10 to move the first ultrasonic probe 40 and the second ultrasonic probe 50 together in the X-axis direction (left-right direction).

[0034] The Y-axis scanning unit 62 is provided in a pair on both sides in the X-axis direction outside the water tank 10 to move the first ultrasonic probe 40 and the second ultrasonic probe 50 together in the Y-axis direction (front-back direction).

[0035] The Z-axis scanning unit 63 is mounted on the X-axis scanning unit 61 via a slider 65 to move the first ultrasonic probe 40 in the Z-axis direction (up-down direction). In addition, the first ultrasonic probe 40 is mounted on the Z-axis scanning unit 63 via a probe holder 64.

[0036] An arm 66 on which the second ultrasonic probe 50 is mounted is provided on the slider 65. The arm 66 extends downward in the Z-axis direction and extends in the Y-axis direction (horizontal direction). The second ultrasonic probe 50 is located at a position facing the first ultrasonic probe 40 at the front end of the arm 66. In addition, the second ultrasonic probe 50 does not move in the Z-axis direction. In addition, in the present embodiment, the second ultrasonic probe 50 is fixed in the Z-axis direction, but it may also be configured such that the second ultrasonic probe 50 moves in the Z-axis direction (up-down direction) together with the first ultrasonic probe 40.

[0037] The wafer 2 is held by a specimen stage 20 and is disposed in the water W accumulated in the water tank 10. In addition, the first ultrasonic probe 40 is disposed on the upper side of the wafer 2 in the Z-axis direction, and the second ultrasonic probe 50 is disposed on the lower side of the wafer 2 in the Z-axis direction.

[0038] The specimen stage 20 on which the wafer 2 is mounted is held by a specimen stage holding unit 30 that holds the specimen stage 20. The specimen stage holding unit 30 is located in the water W and is fixed to the bottom of the water tank 10 via legs 22. In addition, a space for the second ultrasonic probe 50 to move in the X-axis direction and the Y-axis direction is formed between the specimen stage holding unit 30 and the bottom surface of the water tank 10. In addition, the case where the legs 22 are provided at the four corners of the specimen stage holding unit 30 is described as an example, but as long as the specimen stage holding unit 30 can be fixed to the water tank 10, it is not limited to the present embodiment.

[0039] Figure 3is a perspective view showing a state where the sample stage is mounted on the sample stage holding portion, Figure 4 It is shown from Figure 3 A three-dimensional view of the sample stage holding portion with the pressing component removed. Figure 5 yes Figure 4 In addition, Figures 3 to 5 In both drawings, the state in which the wafer 2 is not mounted on the sample stage 20 is shown.

[0040] like Figure 3 as well as Figure 4 As shown, the sample table 20 has a circular opening 21 formed on a thin plate. In addition, the thickness of the sample table 20 is a thickness that can ensure rigidity that can stably support the wafer 2 when it is placed, for example, it is set to a thickness of about 2 to 10 mm. In addition, as a material for the sample table 20, a strong component such as aluminum or stainless steel is preferred. By using such a material, it is less susceptible to the vibration of the first ultrasonic probe 40 and the second ultrasonic probe 50 (probe) when moving in the water W. In addition, the shape of the sample table 20 is not limited to a rectangle, for example, it can also be an ellipse.

[0041] The sample table 20 is provided with a supporting component 71 for holding the chip 2 at the opening 21. In addition, the sample table 20 is provided with a pressing component 72 for pressing the chip 2 at the edge of the upper surface side of the opening 21. The edge of the chip 2 is clamped by the supporting component 71 and the pressing component 72, so that the chip 2 is held in the opening 21. At the edge of the opening 21, three pairs of supporting components 71 and pressing components 72 (hereinafter collectively referred to as holding components) are arranged in a manner to stably hold the chip 2. In addition, as long as at least three holding components are provided, the chip 2 can be stably held, but depending on the size of the chip 2, it can be less than 2 or more than 4.

[0042] The pressing member 72 is formed elongated along the edge of the opening 21 and is disposed at a position facing the support member 71 in the vertical direction. The pressing member 72 is screwed to the edge of the opening 21 of the sample stage 20. In this embodiment, the pressing member 72 is fixed at both ends in the longitudinal direction.

[0043] The sample stage holding part 30 holds the sample stage 20 and is configured to include: a sample stage lower pressing member 31 that presses the lower side of the sample stage 20; and a sample stage upper pressing member 32 that presses the upper side of the sample stage 20. In this way, the sample stage holding part 30 is formed in a U shape and holds both sides of the sample stage 20 in the X-axis direction. That is, the sample stage lower pressing member 31 has: a lower pressing part 31a that is arranged along the edges of both sides of the sample stage 20 in the X-axis direction; and a connecting part 31b that connects the ends (inner ends) of the lower pressing part 31a in the Y-axis direction to each other. The sample stage upper pressing member 32 is arranged along the edges of both sides of the sample stage 20 in the X-axis direction and is arranged overlapping the lower pressing part 31a. In addition, the sample stage upper pressing member 32 is fixed to the lower pressing part 31a by screwing. In addition, a positioning member 33 for the rear end of the sample stage 20 to abut against and determine the insertion position of the sample stage 20 is provided on the upper surface of the connecting part 31b of the sample stage holding part 30.

[0044] As Figure 5 shown, the carrier member 71 is formed to project radially inward from the peripheral wall surface 21a of the opening 21. In addition, the carrier member 71 is formed in a trapezoidal shape, and an abutting part 71a that abuts against the outer periphery of the wafer 2 is formed at the front end on the inner diameter side. In addition, on the carrier member 71, a support part 71b that projects radially inward and supports the wafer 2 is formed at the lower end of the abutting part 71a. The support part 71b is in a flange shape and abuts against and supports the lower surface of the edge part of the wafer 2. By providing three carrier members 71 in this way, the positioning of the wafer 2 with respect to the opening 21 is performed, and a gap S is formed between the outer periphery of the wafer 2 and the peripheral wall surface 21a of the opening 21 (see Figure 1 ).

[0045] Figure 6 is a perspective view showing the state in which the sample stage is held by the sample stage holding part. In addition, in Figure 6 , a state of one side of the sample stage holding part 30 in the X-axis direction as viewed from the near front side in the Y-axis direction is illustrated.

[0046] As Figure 6 shown, the part of the sample stage 20 except for both ends in the Y-axis direction is cut into a concave shape, and held parts 20a, 20a held by the sample stage holding part 30 are formed at both ends in the Y-axis direction.

[0047] The portion of the upper-side pressing member 32 of the specimen stage, except for both ends in the Y-axis direction, is cut into a concave shape, and pressing portions 32a are formed at both ends in the Y-axis direction and are arranged so as to overlap the held portion 20a. Inside the pressing portion 32a, a cutout 32b for slidably guiding the held portion 20a of the specimen stage 20 is formed. That is, the held portion 20a is inserted from the near front side in the Y-axis direction and is inserted into a predetermined position of the specimen stage holding portion 30 while sliding. In addition, in the present embodiment, only one side in the X-axis direction is illustrated, but the other side is configured in the same manner.

[0048] Figure 7 It is a top view showing a state where a specimen stage on which a wafer is mounted is mounted on a specimen stage holding portion.

[0049] As Figure 7 shown, the diameter R1 of the opening 21 is formed to be larger than the diameter R2 of the wafer 2. Thereby, a gap S (bubble discharge portion) for discharging bubbles is formed between the (edge portion) of the opening 21 formed in the specimen stage 20 and the outer periphery of the wafer 2. The gap S is an arc-shaped hole formed to penetrate in the axial direction (direction perpendicular to the paper surface) of the opening 21. In addition, the position where the carrier member 71 is provided and the position where the pressing member 72 is provided block a hole penetrating in the vertical direction (Z-axis direction). That is, the opening 21 has a gap S at the outer peripheral portion of the wafer 2 except for the arrangement position of the holding member by holding the wafer 2. The larger the gap S, the easier it is to discharge bubbles. On the other hand, in order to hold the wafer 2, the holding member needs to be configured larger.

[0050] In addition, by bringing the wafer 2 into contact with the contact portion 71a of the carrier member 71 (see Figure 5 ), the wafer 2 is positioned in the opening 21, and the gap S can be reliably ensured between the opening 21 and the wafer 2. In addition, the size of the gap S (radial distance between the edge portion of the opening 21 and the outer peripheral portion of the wafer 2) is appropriately set according to the purpose and the like within a range that does not impair the effect.

[0051] In addition, the wafer 2 is pressed by the pressing member 72 so that the wafer 2 does not fall off from the opening 21. The pressing member 72 is an elongated plate shape formed to extend in the circumferential direction, and a bent portion 72a having a shape along the curvature of the outer periphery of the wafer 2 is formed on the inner side in the radial direction. Thereby, the area where the wafer 2 and the pressing member 72 overlap in the Z-axis direction (direction perpendicular to the paper surface) can be reduced, and the inspection range of the wafer 2 can be expanded.

[0052] In addition, the materials of the carrier member 71 and the pressing member 72 are not particularly limited as long as they do not damage the wafer 2. For example, resin members such as polyethylene and acrylic can be cited. Although not shown, by making the threaded hole when fixing the pressing member 72 with a screw a long hole that is longer in the direction of the wafer 2 (the object to be inspected), the pressing member 72 can move within the range of the long hole, so the operation when setting the wafer 2 becomes easy.

[0053] In addition, a leaf spring 80 for holding the specimen stage 20 is provided at the pressing portion 32a of the upper-side pressing member 32 on the specimen stage. By inserting the held portion 20a of the specimen stage 20 (refer to Figure 6 ) into the position of the pressing portion 32a, the held portion 20a is held by the leaf spring 80. Thereby, the specimen stage 20 is stably held by the specimen stage holding portion 30. In addition, in the present embodiment, the case where the leaf spring 80 is provided at the four corners of the specimen stage 20 has been described as an example, but as long as it is a structure capable of holding the specimen stage 20, it may be two portions on the near side, or two portions on the inner side, and the number and position of the leaf springs 80 are not limited.

[0054] Figure 8 It is a plan view showing a state in the middle of installing the specimen stage holding the wafer on the specimen stage holding portion.

[0055] As Figure 8 shown, after holding the wafer 2 on the specimen stage 20, the specimen stage 20 is horizontally arranged on the near side in the Y-axis direction of the specimen stage holding portion 30, and the inner held portion 20a is inserted from the near side of the specimen stage holding portion 30 and slides toward the inner side in the Y-axis direction. Thereby, the held portion 20a is inserted between the lower pressing portion 31a and the near-side pressing portion 32a while being guided toward the inner side in the Y-axis direction. And after the held portion 20a passes through the pressing portion 32a, the inner held portion 20a reaches between the lower pressing portion 31a and the pressing portion 32a on the inner side in the Y-axis direction, and the held portion 20a on the near side in the Y-axis direction reaches the near-side pressing portion 32a. By further sliding the specimen stage 20 inward and pressing it from this state, all the held portions 20a at the four corners are inserted between the lower pressing portion 31a and the pressing portion 32a, and the held portions 20a are respectively held by the leaf spring 80.

[0056] Next, the steps from setting the wafer 2 on the specimen stage 20 to setting the specimen stage 20 on the specimen stage holding portion 30 are shown.

[0057] First, the wafer 2 is placed on the opening 21 of the specimen stage 20. Thereby, the edge portion of the wafer 2 is supported by the carrier member 71, and the outer peripheral surface of the wafer 2 abuts against the abutting portion 71a, so that the wafer 2 is positioned in the opening 21 in a state where a gap S is formed between the outer periphery of the wafer 2 and the opening 21 (refer toFigure 5 , Figure 7 ). Then, the pressing member 72 is disposed at the edge of the opening portion 21 so as to overlap with the edge of the wafer 2, and the pressing member 72 is fixed to the specimen stage 20 using screws. In this way, the wafer 2 is fixed to the specimen stage 20 by the holding members (the carrier member 71 and the pressing member 72).

[0058] Then, the specimen stage 20 on which the wafer 2 is fixed is immersed in the water W in the water tank 10, and the specimen stage 20 is tilted or the like to remove the bubbles remaining on the lower surface of the wafer 2. In addition, in the case where bubbles that cannot be removed even by the above steps remain, the bubbles are removed by blowing a water stream to the portion where the bubbles are confirmed. In particular, the fine bubbles remaining between the wafer 2 and the opening portion 21 are removed through the gap S (bubble discharge portion) by the water stream. In addition, the narrower the gap S, the faster the water stream at the time of blowing, and the wider the gap S, the slower the water stream at the time of blowing.

[0059] Then, with the specimen stage 20 holding the wafer 2 being in a horizontal state near the front side of the specimen stage holding portion 30, it is slidably inserted from the front side of the specimen stage holding portion 30, whereby the specimen stage 20 is fixed to the specimen stage holding portion 30. In addition, the specimen stage holding portion 30 is fixed in the water tank 10 (see Figure 2 ).

[0060] In this way, after the wafer 2 can be fixed to the specimen stage 20 outside the water tank 10, the specimen stage 20 is placed in the water W and slidably inserted into the specimen stage holding portion 30 for fixing, so that the workability when fixing the wafer 2 is improved.

[0061] Next, the operation and function of the ultrasonic imaging device 1 will be described.

[0062] When the wafer 2 (specimen) to be inspected is put into the water W, in order to inspect the inside of the wafer 2, the first ultrasonic probe 40 and the second ultrasonic probe 50 are horizontally moved relative to the specimen stage 20 and scanned on the wafer 2. In addition, before the inspection, the first ultrasonic probe 40 is moved upward and retracted from the second ultrasonic probe 50, and when the wafer 2 is disposed at a specified position, the first ultrasonic probe 40 is lowered from the origin position to the focal position.

[0063] The ultrasonic imaging device 1 images the intensity of the received ultrasonic waves by utilizing the property that the intensity of the ultrasonic waves transmitted through the wafer 2 due to the acoustic impedance of each part of the wafer 2 (specimen) is different. Thus, the state inside the wafer 2 can be inspected in a non-destructive manner.

[0064] Next, the operation method of the ultrasonic imaging device 1 will be described.

[0065] In order to obtain a desired effect in the ultrasonic imaging device 1 with a bubble discharging mechanism according to the present embodiment, test operation is performed in the pre-stage before the formal operation of the ultrasonic imaging device 1.

[0066] In this test operation, the area and shape of the opening 21 provided in the specimen stage 20 are set according to the area and shape of the subject (wafer 2) to be inspected. That is, the area and shape of the opening 21 are set so that when the subject (wafer 2) is held by the holding members (carrying member 71 and pressing member 72), a gap S (bubble discharging portion) of a sufficient size for discharging bubbles is formed between the subject (wafer 2) and the opening 21. Through this test operation, it is possible to prevent bubbles from remaining around the subject (wafer 2) also in this operation, and the operation efficiency can be improved.

[0067] As described above, the ultrasonic imaging device 1 according to the present embodiment is an ultrasonic imaging device 1 that irradiates ultrasonic waves to the wafer 2, obtains its transmitted wave, and images it, and includes a specimen stage 20 that fixes the wafer 2 in water W. The specimen stage 20 has an opening 21, and holding members (carrying member 71 and pressing member 72) for holding the wafer 2 are provided at the edge of the opening 21. The opening 21 is configured to be larger than the wafer 2, and a gap S (bubble discharging portion) is formed between the outer peripheral portion of the wafer 2 and the edge of the opening 21 by holding the wafer 2 with the holding members. Thus, fine bubbles attached around the wafer 2 mounted on the specimen stage 20 can be simply discharged from the gap S.

[0068] In addition, in the present embodiment, the gap S (bubble discharging portion) is formed at a position other than the position where the holding members are disposed. Thus, the holding members can be configured to stably hold the wafer 2.

[0069] In addition, in the present embodiment, there are three or more holding members (carrying member 71 and pressing member 72), and the holding members are arranged at equal intervals at the edge of the opening 21. Thus, the wafer 2 can be stably held on the specimen stage 20.

[0070] In addition, in the present embodiment, the holding members are composed of a carrying member 71 disposed below the wafer 2 and placing the wafer 2 thereon and a pressing member 72 disposed above the wafer 2 and pressing the wafer 2. Thus, by pressing the edge of the wafer 2 up and down, the wafer 2 can be stably held on the specimen stage 20.

[0071] In addition, in the present embodiment, the specimen stage 20 is held by a specimen stage holding portion 30, and the specimen stage holding portion 30 is fixed to the water tank 10 in which the specimen stage 20 is immersed. Thus, since the wafer 2 is fixed to the specimen stage 20 outside the water tank 10, the workability is improved as compared with the case where the wafer 2 is fixed inside the water tank 10.

[0072] The present invention is not limited to the above-described embodiments. For example, in the present embodiment, the case of the circular opening 21 has been described as an example, but it is not limited to a circle, and the shape of the portion of the opening other than the holding member may be a shape that bulges outward, and the gap between the opening and the outer periphery of the wafer 2 may be larger than that in the present embodiment.

Claims

1. An ultrasonic imaging device for irradiating a subject with ultrasonic waves, obtaining the transmitted waves and imaging them, characterized in that: A sample stand is provided for fixing the specimen in water. The sample stage has an opening. A holding member for holding the subject is provided at the edge of the opening. The opening is configured to be larger than the subject, and the subject is gripped by the gripping member, so that a bubble discharge portion is formed between an outer peripheral portion of the subject and an edge of the opening.

2. The ultrasonic imaging device according to claim 1, characterized in that: The bubble discharge portion is formed at a position other than a position where the holding member is disposed.

3. The ultrasonic imaging device according to claim 1, characterized in that: The holding members are provided in three or more numbers, and the holding members are arranged at equal intervals on the edge of the opening.

4. The ultrasonic imaging device according to claim 1, characterized in that: The holding member includes a placing member that is disposed on the lower side of the subject and places the subject thereon, and a pressing member that is disposed on the upper side of the subject and presses the subject.

5. The ultrasonic imaging device according to claim 1, characterized in that: The sample stage is held by a sample stage holding portion, The sample stage holding portion is fixed to a water tank in which the sample stage is immersed in water.

Images