Control device, ultrasound inspection device, and ultrasound inspection method

Abstract

The invention provides a control device capable of improving the accuracy of defect detection. [Solution] The control device 7 controls an ultrasonic inspection device 100 that ultrasonically inspects an object to be inspected 5 by irradiating it with ultrasonic waves and receiving reflected waves, and includes an acquisition unit 71 that acquires a first reflected signal received from a first ultrasonic irradiation position on the object to be inspected 5 and a second reflected signal received from a second ultrasonic irradiation position on the object to be inspected, the distance between the second irradiation position and the first irradiation position being shorter than the beam diameter of the ultrasonic waves on the surface of the object to be inspected 5, and an integration unit 72 that integrates the first reflected signal and the second reflected signal to generate an integrated reflected signal.

Description

[Technical Field]

[0001] This disclosure relates to a control device, an ultrasound inspection device, and an ultrasound inspection method. [Background technology]

[0002] Ultrasonic inspection equipment generates an inspection image of the desired interface by repeatedly irradiating the object to be inspected (the object being inspected, the sample) from a probe and receiving reflected waves from within, such as at a bonding interface or internal defects. By applying appropriate processing to the inspection image, defects can be detected. In semiconductors, which are the main objects being inspected, the miniaturization and stacking of circuit patterns are progressing, increasing the need for inspections that can detect even minute bonding defects.

[0003] Patent Document 1 describes an ultrasonic imaging device 100 that irradiates an object made of multiple layers with ultrasonic waves to acquire reflected waves from the bonding interface of the object and generates an image of the bonding interface based on the signal intensity of the reflected waves, comprising: a matching processing unit 56 that corrects the phase difference of a second reflected wave from a second irradiation point on the object with respect to a first reflected wave from a first irradiation point on the object; and a pixelation information generation processing unit (averaging processing unit 57) that removes noise from the first reflected wave based on the first reflected wave and the second reflected wave after phase correction, and generates pixelation information of the portion of the bonding interface that returned the interface echo based on the signal intensity of the interface echo that shows the waveform from the bonding interface among the first reflected waves from which the noise has been removed. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2024-11497 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] The technology described in Patent Document 1 uses multiple different irradiation points (a first irradiation point and a second irradiation point) among the irradiation points of the ultrasonic beam to obtain a clear interface echo with noise removed (paragraphs 0025-0027, Figures 3 and 4, etc.). However, Patent Document 1 does not describe improving detection accuracy by focusing on the beam diameter of the ultrasonic beam and detecting minute defects. The problem that this disclosure aims to solve is to provide a control device, an ultrasonic inspection device, and an ultrasonic inspection method that can improve the accuracy of defect detection. [Means for solving the problem]

[0006] The control device of the present disclosure is a control device for an ultrasonic inspection apparatus that ultrasonically inspects an object to be inspected by irradiating it with ultrasonic waves and receiving reflected waves, and comprises: an acquisition unit that acquires a first reflected signal received from a first ultrasonic irradiation position on the object to be inspected and a second reflected signal received from a second ultrasonic irradiation position on the object to be inspected, the distance from which to the first irradiation position is shorter than the beam diameter of the ultrasonic waves on the surface of the object to be inspected; and an integration unit that integrates the first reflected signal and the second reflected signal to generate an integrated reflected signal. Other solutions will be described later in the embodiments for carrying out the invention. [Effects of the Invention]

[0007] This disclosure provides a control device, an ultrasonic inspection device, and an ultrasonic inspection method that can improve the accuracy of defect detection. [Brief explanation of the drawing]

[0008] [Figure 1] This is a block diagram illustrating the concept of an ultrasound examination apparatus according to the first embodiment. [Figure 2] This is a block diagram showing the specific hardware configuration of the control device. [Figure 3] This is a schematic block diagram of an ultrasound examination apparatus according to the first embodiment. [Figure 4] This diagram illustrates the relationship between relatively large defects and the reflectivity of ultrasound. [Figure 5] This is a diagram explaining the relationship between relatively small defects and the ultrasonic reflection intensity. [Figure 6] This is a graph (example) showing the reflection signal when ultrasonic waves are emitted against the defects shown in FIG. 4. [Figure 7] This is a graph (example) showing the reflection signal when ultrasonic waves are emitted against the defects shown in FIG. 5. [Figure 8] This is a graph (reference example) showing the reflection signal when ultrasonic waves are emitted against an inspection object without defects. [Figure 9] This is a flowchart showing the ultrasonic inspection method in the first embodiment. [Figure 10] This is a diagram explaining the first irradiation position and the second irradiation position. [Figure 11] This is a diagram explaining the relationship between the ultrasonic irradiation position and the position of the defect. [Figure 12] This is a flowchart showing the integration method of the reflection signal. [Figure 13A] This is a graph showing the first reflection signal and one group of second reflection signals superimposed before phase correction. [Figure 13B] This is an enlarged graph of part A in FIG. 13A. [Figure 13C] This is a graph in which the peak (local peak) of the second reflection signal and the first reflection signal are superimposed to coincide on the time axis. [Figure 14] This is a graph showing the first reflection signal and a plurality of second reflection signals (reflection signal group) superimposed before phase correction. [Figure 15] This is a graph showing the first reflection signal and a plurality of second reflection signals (reflection signal group) superimposed after phase correction. [Figure 16] This is a graph showing the xy integrated reflection signal obtained by phase correction and integration after weighted addition. [Figure 17] This is a diagram showing the whole process performed in the first embodiment. [Figure 18] This is a flowchart showing the ultrasonic inspection method in the third embodiment. [Figure 19] This figure shows the overall process performed in the third embodiment. [Modes for carrying out the invention]

[0009] The following describes embodiments for implementing this disclosure, with reference to the drawings. The following is merely an example of how to implement the invention related to this disclosure, and this disclosure is not limited to the following example. Within the description of one embodiment below, other embodiments applicable to that embodiment will also be described as appropriate. This disclosure is not limited to the following embodiment, and different embodiments can be combined or modified as appropriate without significantly impairing the effects of this disclosure. In addition, the same reference numerals will be used for the same components, and redundant explanations will be omitted. Furthermore, components having the same function will be given the same name. The illustrations are schematic, and for illustrative purposes, the actual configuration may be changed or some components may be omitted or modified between drawings without significantly impairing the effects of this disclosure. Also, the same embodiment does not necessarily need to have all the components.

[0010] Figure 1 is a block diagram illustrating the concept of an ultrasonic inspection apparatus 100 according to the first embodiment. The ultrasonic inspection apparatus 100 is a device that ultrasonically inspects an object to be inspected 5 by irradiating it with ultrasonic waves (incident waves) and receiving reflected waves 4. The object to be inspected 5 is, for example, a multilayer semiconductor (wafer), a miniature electromechanical system (MEMS), a metal structure, etc. In the following example, the object to be inspected 5 is a multilayer semiconductor, and the ultrasonic inspection apparatus 100 inspects for the presence or absence of defects that may exist at the bonding interface (inspection surface) between the stacked semiconductors. The ultrasonic inspection apparatus 100 of this disclosure generates an inspection image of the inspection surface, and can therefore also be called an inspection surface image generation device.

[0011] The ultrasonic inspection apparatus 100 comprises a probe 2 (ultrasonic probe) that irradiates (transmits, emits) ultrasonic waves and receives reflected waves, a flaw detector 3, and a scanning measuring device 13 that drives the probe 2 in the xy direction in a horizontal plane. The flaw detector 3 drives the probe 2 by supplying it with a pulse signal. The scanning measuring device 13 includes an actuator (not shown) that drives the probe 2 in the xy direction (in the xy plane). The ultrasonic inspection apparatus 100 also includes a detection unit 1 for detecting defects. In this example, the probe 2, flaw detector 3, and scanning measuring device 13 are provided in the detection unit 1.

[0012] A probe 2, driven by a flaw detector 3 (controlled to emit and receive ultrasonic waves), irradiates an inspection area of ​​a multilayer semiconductor, an example of an object to be inspected 5, with ultrasonic waves at predetermined intervals (hereinafter referred to as the scanning pitch). The ultrasonic waves are reflected from the surface of the object to be inspected 5 and from predetermined locations inside the object to be inspected 5 (e.g., bonding interfaces), generating reflected waves 4. The probe 2 receives the reflected waves 4, and the flaw detector 3 processes the reflected waves 4 as needed to convert them into reflected intensity (reflected signal intensity). The converter 6 (A / D converter) converts the converted reflected signal into digital waveform data and inputs it to the control device 7.

[0013] Figure 2 is a block diagram showing the specific hardware configuration of the control device 7. The control device 7 is a device that controls, for example, the operation and driving of the ultrasound examination apparatus 100. The control device 7 is configured with, for example, a CPU (Central Processing Unit) 1001, RAM (Random Access Memory) 1002, ROM (Read Only Memory) 1003, I / F (Interface) 1004, bus 1005, etc. The CPU 1001, RAM 1002, ROM 1003, and I / F 1004 are connected, for example, via bus 1005. The control device 7 is realized when a predetermined control program (for example, the control method, ultrasound examination method, image generation method, etc. of this disclosure) stored in ROM 1003 is loaded into RAM 1002 and executed by CPU 1001. The exchange of signals and information between the control device 7 and various devices (probe 2, scanning measurement device 13, server, personal computer, etc.) and external networks is carried out in hardware terms through I / F 1004.

[0014] Returning to Figure 1, the control device 7 receives parameters from the user. The control device 7 is connected to a user interface unit 17 (an example of an output device 8 such as a monitor), and a storage device 18, both of which will be described later. The user interface unit 17 is a monitor, for example, a touch panel type, equipped with input and display functions. The user interface unit 17 displays information such as images of defects detected by the control device 7, the number of defects, the coordinates and dimensions of each defect, and furthermore, the detected defects are color-coded by defect type and superimposed on the wafer. The storage device 18 stores characteristic quantities of defects detected by the control device 7 (size, width, dimensions, aspect ratio, etc.), inspection images, etc.

[0015] The control device 7 comprises an acquisition unit 71, an integration unit 72, an image generation unit 73, a defect detection unit 74, and an output unit 75. The reflected signal (waveform data) from the converter 6 is input to the acquisition unit 71. The integration unit 72 generates an integrated reflected signal, which will be described in detail later. The specific method for generating the integrated reflected signal will be described later. The generated integrated reflected signal is input to the image generation unit 73.

[0016] The image generation unit 73 determines pixel values ​​from the signal intensity of the integrated reflection signal (digital waveform data) obtained by the integration processing by the integration unit 72, and generates an inspection image of, for example, a joint interface (a cross-sectional image of a specific joint surface) of the object to be inspected 5 from the determined pixel values. Specifically, for example, the image generation unit 73 scans the measurement range (region in the xy plane) of the object to be inspected 5 with the scanning measuring device 13, and converts the digital data at each scanning position obtained by analog / digital conversion into grayscale values ​​(for example, 0 to 255 when generating a 256-level image). As a result, the image generation unit 73 generates an inspection image showing a plane in the xy direction (a plane parallel to the surface of the object to be inspected 5) at a specific depth (position in the z direction) from the surface of the object to be inspected 5.

[0017] The defect detection unit 74 detects defects by performing appropriate processing on the inspection image generated by the image generation unit 73, such as binarization. The defect detection unit 74 classifies the detected defects into several types. For example, the defect detection unit 74 classifies them into large voids, small voids, cracks, delaminations, etc., according to their size.

[0018] The output unit 75 integrates inspection results such as information on individual defects (defect type, location, size, etc.) and inspection images (images for observing cross-sections) detected by the defect detection unit 74. The output unit 75 generates output data for the integrated data and outputs it to the output device 8 (for example, a display device such as the user interface unit 17, or another control device).

[0019] Figure 3 is a schematic block diagram of the ultrasonic inspection apparatus 100 according to the first embodiment. Figure 3 shows a Cartesian coordinate system 10 consisting of x, y, and z coordinates. The x and y directions are, for example, horizontal directions, and the x and y plane is, for example, a horizontal plane. The z direction is, for example, vertical directions, and is also the height direction.

[0020] The detection unit 1 comprises a scanner stand 11 and a water tank 12 mounted on the scanner stand 11. The scanning measurement device 13 is a device that moves the probe 2 in the x, y, and z directions, mounted on the scanner stand 11 so as to straddle the water tank 12. A holder 15 is attached to the scanning measurement device 13, and the scanner 11 is installed almost horizontally. Water 14 is poured into the water tank 12 to a position (indicated by the dotted line) where the object to be inspected 5 is submerged, and the object to be inspected 5 is placed at the bottom (in the water) of the water tank 12. The water 14 is used to efficiently propagate the ultrasonic waves emitted from the probe 2 into the interior of the object to be inspected 5. The mechanical controller 16 is part of the control device 7 and drives the scanning measurement device 13 to move the probe 2 in the x, y, and z directions. The mechanical controller 16 drives the scanning measurement device 13 based on control commands from the acquisition unit 71, etc. The flaw detector 3 is also driven by commands from the control device 7.

[0021] Probe 2 emits ultrasonic waves towards the object to be inspected 5 and receives the reflected waves 4 that return from the object to be inspected 5. Probe 2 is mounted on a holder 15 and moves freely in the x, y, and z directions by a scanning measuring device 13. As a result, probe 2 irradiates ultrasonic waves at multiple pre-set measurement points on the object to be inspected 5 while moving in the x and y directions. Simultaneously, probe 2 receives the reflected waves 4. In this way, a cross-sectional image (two-dimensional inspection image) of the joint interface within the measurement range (xy plane) can be obtained, and the presence or absence of defects can be inspected. Probe 2 is connected to a flaw detector 3 that converts the reflected waves 4 into a reflection intensity signal.

[0022] The parameter setting unit 76 in the control device 7 receives parameters such as measurement conditions (recipes) input from an external source and sets them in the defect detection unit 74 and the output unit 75. The parameter setting unit 76 is connected to the database 77.

[0023] Figure 4 illustrates the relationship between relatively large defects 42a and the reflection intensity of the ultrasonic beam 41. Figure 5 illustrates the relationship between relatively small defects 42b and the reflection intensity of the ultrasonic waves. First, as a characteristic of ultrasonic waves, they propagate inside the object being inspected 5, and when there is a boundary where the material properties (acoustic impedance) change, some of the waves are reflected. In particular, if there is an air gap, most of the waves are reflected. For this reason, bonding defects (air gaps) such as voids and delaminations can be detected with high sensitivity from the reflection intensity at the bonding interface inside the object being inspected 5.

[0024] The ultrasonic beam 41 (ultrasound), shown in shaded areas, is emitted from the probe 2 toward defects 42a and 42b, and also diffuses away from the probe 2 relative to the defects 42a and 42b. Normally, the height position of the probe 2 is adjusted so that the ultrasonic beam is focused on the bonding interface (surface under inspection). The ultrasonic beam 41 is narrowed near defects 42a and 42b, as indicated by the pair of opposing arrows in Figures 4 and 5. Therefore, the ultrasonic beam 41 has a finite spread. Hereafter, the size of this spread will be referred to as the beam diameter. The beam diameter can be defined as the diameter of the circle formed by connecting the parts where the ultrasonic intensity is at a predetermined ratio (e.g., 50%), with the part with the highest ultrasonic intensity (e.g., the center of the ultrasonic beam) as the intensity center.

[0025] The size of defect 42a is relatively large relative to the beam diameter, and its reflected wave can be obtained from the ultrasonic irradiation position. On the other hand, the size of defect 42b (Figure 5) is small relative to the beam diameter, so at the ultrasonic irradiation position, reflected waves from the surrounding area (within the beam diameter) are obtained along with the reflected wave from the defect.

[0026] Figure 6 is a graph showing the reflected signal when ultrasonic waves are emitted towards defect 42a shown in Figure 4 (example). Figure 7 is a graph showing the reflected signal when ultrasonic waves are emitted towards defect 42b shown in Figure 5 (example). Figure 8 is a graph showing the reflected signal when ultrasonic waves are emitted towards the inspection target 5, which does not have defects (reference example). In Figures 6 to 8, the horizontal axis is the signal reception time (time t), and the vertical axis is the intensity (intensity of the reflected signal). The reception time shown on the horizontal axis can be converted to the depth (height position) where the reflected wave 4 was generated. Therefore, the reception time can also be said to be in the z direction. In Figures 6 and 7, the dashed line indicates the time when the reflected wave 4 from the bonding interface containing defects 42a and 42b was received. In Figure 8, the dashed line indicates the time at the same time as in Figures 6 and 7. In Figures 6 to 8, the graphs were measured under the same measurement conditions except for the difference between defects 42a and 42b.

[0027] As shown within the dashed box in Figure 6, a strong reflected wave 4 is obtained from a relatively large defect 42a. However, as shown within the dashed box in Figure 7, the reflected wave 4 from a relatively small defect 42b is buried (averaged) by the reflected wave 4 from the vicinity of defect 42a. As a result, only a signal with almost the same intensity as that of a location without defect 42b is obtained, as shown in Figure 8. Furthermore, even outside the dashed line, electrical noise with an intensity equivalent to that of a minute defect 42b is generated, and this is superimposed on the reflected wave 4 from the junction interface. Therefore, across the entire range of the graph shown in Figure 7, the signal intensity is the same as that of the graph in Figure 8 where no defects exist, indicating room for improvement in the accuracy of defect detection.

[0028] Therefore, in this disclosure, in order to obtain a weak reflected signal from a minute defect such as defect 42b, the signal intensities in the xy plane (xy direction) and the time direction (z direction) are, for example, integrated (averaged). This generates an integrated reflected signal, and based on the integrated intensity value, an inspection image in which minute defects are revealed can be generated.

[0029] Figure 9 is a flowchart of the ultrasonic inspection method in the first embodiment. The ultrasonic inspection method of the present disclosure shown in Figure 9 can be performed using the ultrasonic inspection apparatus 100 described above. With reference to Figure 9, the functional parts of the control device 7 provided in the ultrasonic inspection apparatus 100 will also be described as appropriate. The ultrasonic inspection method of the present disclosure is a method of ultrasonically inspecting an object to be inspected 5 by irradiating it with ultrasound and receiving the reflected waves. The ultrasonic inspection method of the present disclosure is also a method for generating an inspection image (defect image), and can therefore be said to be a method for generating an inspection image of the inspection surface.

[0030] The acquisition unit 71 (part of the functional unit) provided in the control device 7 first acquires a first reflected signal received from the first irradiation position P0 (described later with reference to Figures 10 and 11), which is the measurement point of interest (step S101). The first irradiation position P0 is one of the positions where ultrasound is irradiated, for example, the center of the beam circle of the irradiated ultrasound. Therefore, the acquisition unit 71 acquires a first reflected signal received from the first irradiation position P0 of the ultrasound on the object to be inspected 5.

[0031] Next, the acquisition unit 71 acquires the second reflected signals received from one or more second irradiation positions P1 to P8 (described later with reference to Figures 10 and 11) of the ultrasonic waves on the object to be inspected 5 (step S102). The second irradiation positions P1 to P8 are irradiation positions in the xy plane where the distance from the first irradiation position P0 is shorter than the ultrasonic beam diameter 52 (Figure 10) at the surface of the object to be inspected 5 (e.g., the bonding interface). That is, the distance between the first irradiation position P0 and the second irradiation positions P1 to P8 is shorter than the beam diameter 52. In particular, it is preferable to have multiple second irradiation positions P1 to P8. This can further improve the accuracy of defect detection. Hereinafter, multiple second reflected signals will be collectively referred to as a group of reflected signals.

[0032] In the example of this disclosure, the acquisition unit 71 acquires a first reflected signal from the first irradiation position P0 of interest (for inspection purposes) and a second reflected signal from at least one (preferably all) of, for example, one or more second irradiation positions P1 to P8, and integrates these signals. For example, if only the first reflected signal from the first irradiation position P0 is used, the change in the signal (echo) caused by the defect may be small if the defect is too small, and it may be difficult to distinguish it from noise. As a result, minute results may be overlooked.

[0033] Therefore, in the example of this disclosure, at least one second reflected signal from one or more second irradiation positions P1 to P8 that are within the same beam diameter (the distance to the first irradiation position P0 is less than or equal to the beam diameter) is collected, and the collected second reflected signals are integrated with the first reflected signal. The integration generates a single signal (integrated reflected signal). An ultrasonic beam has some beam diameter, even at the focal point (i.e., it is not completely zero), and the ultrasonic beam has a certain degree of spread. Therefore, even if the first irradiation position P0 of interest (the object to be inspected) is different, the reflected signals based on the beam circles of different ultrasonic beams that irradiate the same defect, i.e., the defects that overlap with the ultrasonic beams, contain information about the defect. Conceptually speaking, if the beam circle when irradiating the first first irradiation position P0 is close enough to the beam circle when irradiating the second first irradiation position P0 (the second irradiation position from the perspective of the first first irradiation position P0) which is near the first first irradiation position P0, then these can be used. Therefore, by integrating these to generate an integrated reflection signal, it is possible to generate a reflection signal that emphasizes defects. In this way, the accuracy of detecting minute defects can be improved.

[0034] There is no limit to the size of detectable defects. For example, defects larger than the beam diameter can certainly be detected, but according to this disclosure, defects smaller than the beam diameter can also be detected, such as defects with a size of 1 / 10 to 1 / 20 of the beam diameter (for example, the length of the longest part of the defect).

[0035] These steps S101 and S102 are acquisition steps that acquire a first reflected signal received from a first ultrasonic irradiation position P0 on the object to be inspected 5, and a second reflected signal received from second ultrasonic irradiation positions P1 to P8 on the object to be inspected 5, where the distance from the first irradiation position P0 is shorter than the ultrasonic beam diameter on the surface of the object to be inspected 5.

[0036] The second irradiation positions P1 to P8 are also positions from which ultrasound is irradiated, and are, for example, the center of the beam circle of the irradiated ultrasound. In other words, by irradiating the object to be inspected 5 with ultrasound at a position slightly shifted from the irradiation position of the ultrasound beam in step S101 (first irradiation position) above, the second reflected signal from the second irradiation positions P1 to P8 can be received. The specific positions and number of points for the second irradiation positions can be input to the control device 7 at the same time as setting the recipe for inspection conditions, etc.

[0037] The shapes of the first irradiation position P0 and the second irradiation positions P1 to P8 can be, for example, a rectangular area, a circular area, a cross-shaped area, etc. The second irradiation positions P1 to P8 are, for example, adjacent to the first irradiation position P0.

[0038] Figure 10 illustrates the first irradiation position P0 and the second irradiation positions P1 to P8. Figure 10 shows the inspection interface 50 (a surface extending in the x and y directions, such as a joint interface) on the object to be inspected 5, and the inspection interface 50 is imaged. In the illustrated example, the first irradiation position P0 and the second irradiation positions P1 to P8 are all squares with the same area. As eight second irradiation positions P1 to P8, four second irradiation positions P2, P4, P5, and P7 are positioned adjacent to the four sides of the square first irradiation position P0, and four second irradiation positions P1, P3, P6, and P8 are positioned to fill the spaces between the second irradiation positions P2, P4, P5, and P7 adjacent to the four sides.

[0039] Circle 51 represents the spread of the ultrasonic beam when ultrasonic waves are emitted from the first irradiation position P0. As described above, the ultrasonic beam has a beam diameter 52 (the diameter of circle 51) at the inspection interface 50, which is the surface to be inspected. The ultrasonic beam reaches its maximum intensity at the first irradiation position P0, for example, and spreads out in a circular manner away from the first irradiation position P0, while gradually decreasing in intensity. The first irradiation position P0 and the second irradiation positions P1 to P8 are within the irradiation range of the same ultrasonic beam, and in the illustrated example, they are within circle 51. This positioning makes it easier to improve the accuracy of defect detection.

[0040] For example, when an ultrasonic beam is irradiated centered on the first irradiation position P0, the reflected signal intensity from the first irradiation position (first reflected signal) is greater than the reflected signal intensity from the second irradiation positions P1 to P8 (second reflected signals). Then, when probe 2 is slightly shifted and the ultrasonic beam is irradiated centered on the second irradiation position P1 before the shift, for example, the intensity of the second reflected signal from the second irradiation position P1 before the shift (which becomes the first reflected signal from the first irradiation position P0 after the shift) is greater than the intensity of the first and second reflected signals from the first irradiation position P0 and the second irradiation positions P2 to P8 before the shift.

[0041] Figure 11 illustrates the relationship between the ultrasound irradiation position and the location of the defect. In practice, ultrasound is irradiated continuously in the x-direction, for example, with the y-direction position (y-coordinate) fixed. Figure 11 shows the measurement point of interest with irradiation position P0b as the first irradiation position. Figure 11 also shows the situation when ultrasound is irradiated with irradiation positions P0a, P0c, and P0d as the first irradiation positions (second irradiation positions when viewed from the perspective of irradiation position P0b as the first irradiation position).

[0042] In Figure 11, line 54 represents the y-direction position of irradiation position P0a, and line 55 represents the y-direction position of irradiation position P0d. The distance between line 54 and line 55 coincides with the beam diameter 52, and irradiation positions P0b and P0a, P0c, and P0d all lie between line 54 and line 55. Furthermore, irradiation positions P0a, P0b, P0c, and P0d are all located within the same beam diameter 52, and in Figure 11 their y-direction positions are also within the beam 52; however, for illustrative purposes in Figure 11, they are shown separated in the x-direction.

[0043] The irradiation positions P0a, P0b, P0c, and P0d are the centers of the ultrasonic beam spread shown by circles 51a, 51b, 51c, and 51d, and are the target measurement points. Of these, irradiation position P0b is the measurement point of interest (first irradiation position). For example, by changing the x and y positions of probe 2, ultrasonic waves can be irradiated to each of the irradiation positions P0a, P0b, P0c, and P0d.

[0044] Even when ultrasound is irradiated to irradiation positions P0a, P0b, P0c, and P0d, the defect 53 is located within the spread of the ultrasound beam indicated by circles 51a, 51b, 51c, and 51d. Preferably, the entire defect 53 is located within circles 51a, 51b, 51c, and 51d, but only a part of the defect 53 may be located within circles 51a, 51b, 51c, and 51d.

[0045] Within circle 51b, in particular, the irradiation position P0b and defect 53 completely overlap. Therefore, at irradiation position P0b, the beam is irradiated near defect 53 with maximum intensity. As a result, the intensity of the reflected signal obtained is also maximum. On the other hand, the ultrasonic beam is also irradiated at irradiation position P0c, which is slightly offset from defect 53, and at irradiation positions P0a and P0d, which are significantly offset. However, at these irradiation positions, the ultrasonic waves are irradiated with an intensity lower than the maximum ultrasonic intensity. Since a portion of defect 53 is included within circles 51a, 51c, and 51d, the ultrasonic waves are irradiated onto defect 53, albeit at a weak intensity. As a result, the reflected signal (echo) from defect 53 can be detected.

[0046] In this way, signals from second irradiation positions (irradiation positions P0a, P0c, P0d) located within the circle 51b, which is within the beam diameter 52 range from the measurement point of interest (irradiation position P0b), are used. Then, by integrating the reflected wave group, which is multiple second reflected signals from multiple second irradiation positions, a reflected wave 4 can be generated that emphasizes the reflected signal from the defect 53. Note that the beam diameter usually differs depending on the specifications of the probe 2. For this reason, irradiation positions P0a, P0c, and P0d can be set for each probe 2 used.

[0047] Returning to Figure 9, in step S103 (integration step), the integration unit 72 (functional unit) integrates the first reflection signal and the second reflection signal to generate an integrated reflection signal. The integration unit 72 integrates the first reflection signal, which is the reflection signal from the first irradiation position P0, and the group of reflection signals from the second irradiation positions P1 to P8 (eight second reflection signals) to generate an xy integrated reflection signal by integrating the reflection signals in the xy direction. That is, the integration unit 72 generates an xy integrated reflection signal as an example of an integrated reflection signal by integrating the first reflection signal and the second reflection signal in the xy direction, which indicate the irradiation direction of the ultrasound. The integration process is a concept that corresponds, for example, to the averaging process in Patent Document 1. However, in the example of this disclosure, "weighting," which will be described in detail later, may be performed during integration.

[0048] Figure 12 is a flowchart illustrating the method for integrating reflected signals. For illustrative purposes, Figure 12 also shows the integration in the z-direction (time axis direction), which will be described later. The group of eight second reflected signals consists of reflected signals adjacent to the first reflected signal, but there is a possibility that phase shifts such as jitter, which is a fluctuation in the time axis direction, may occur. Therefore, the integration unit 72 first detects the phase shift in the time axis direction of each of the eight second reflected signals relative to the first reflected signal (step S601). Next, the integration unit 72 corrects each second reflected signal based on the detected shift so that the phase in the time axis direction is aligned (step S602). In other words, a "matching process" is performed in which each second reflected signal is corrected so as to overlap the phase shifts. Steps S601 and S602 can be performed, for example, by the method described in Patent Document 1 above.

[0049] The integration unit 72 further generates a single xy integrated reflection signal by performing a "weighted addition process" on the first reflection signal and eight second reflection signals that have been "weighted" according to the distance (step S603). The xy integrated reflection signal is obtained through the weighted addition process. The meaning and specific method of weighted addition will be explained with reference to Figures 13 and 14.

[0050] Figure 13A is a graph showing the first reflected signal (solid line) and an arbitrary second reflected signal (dashed line) superimposed before phase correction. Part A, enclosed by a solid line frame, represents the reflected signal (echo) from the joint interface being inspected, and part B, enclosed by a solid line frame, represents the reflected signal (echo) from the surface of the object being inspected 5.

[0051] Figure 13B is an enlarged graph of section A of Figure 13A. Peak 73a is a local peak that is part of the interface echo of the first reflected signal. In the example of this disclosure, the peak of the second reflected signal corresponding to peak 73a, shown by the solid line, is searched for and recognized from the second reflected signal (echo), shown by the dashed line. Specifically, the recognition method involves calculating the normalized cross-correlation coefficient between peak 73a, shown by the solid line, and each of the corresponding candidate peaks 73b and 73c, shown by the dashed lines, and selecting the candidate with the higher correlation coefficient as the corresponding peak.

[0052] Figure 13C is a graph in which the peak 73c of the second reflected signal and the peak 73a (local peak) of the first reflected signal are superimposed so that they coincide on the time axis. By aligning the phases and superimposing the peaks in this way, multiple reflected signals can be integrated. That is, the integration unit 72 generates an integrated reflected signal by aligning the phase of the first reflected signal with the phase of the second reflected signal. Specifically, for example, by aligning the phases of each second reflected signal with respect to a local peak (e.g., peak 73a) and superimposing the peak 73c corresponding to that local peak, multiple second reflected signals can be integrated into the first reflected signal (phase correction; phase alignment).

[0053] As described above, the intensity of the ultrasonic beam decreases with increasing distance from the center. Therefore, the intensity of the resulting echo also decreases with increasing distance from the center (first irradiation position P0). Consequently, if each second reflected signal constituting the group of reflected signals is treated with the same "weight," i.e., added equally, the intensity of the echo at the defect may actually decrease. Therefore, in the example of this disclosure, a "weight" is assigned according to the distance from the measurement point of interest (first irradiation position P0) (the weight decreases as the distance from the center increases), and the reflection intensities of each reflected signal in the group of reflected signals are added together. In the example of this disclosure, such addition is called "weighted addition."

[0054] In this way, the integration unit 72 generates an xy integrated reflection signal (an example of an integrated reflection signal) using a second reflection signal weighted according to the distance between the first irradiation position P0 and the second irradiation positions P1 to P8. By doing so, the influence of the second reflection signal at positions close to the first irradiation position P0 can be increased, while the influence of the second reflection signal at positions far from the first irradiation position P0 can be decreased. As a result, the xy integrated reflection signal can be generated by effectively using the second reflection signal, which has a higher intensity due to its proximity.

[0055] In the example of this disclosure, when the distance from the measurement point of interest, i.e., the distance between the first irradiation position and the second irradiation position, is the first distance, the integration unit 72 generates an xy integrated reflection signal (an example of an integrated reflection signal) using the second reflection signal multiplied by a first coefficient. The second reflection signal multiplied by the first coefficient is a signal value obtained by multiplying the measured value (intensity) of the second reflection signal by a predetermined first coefficient. Furthermore, when the distance is the second distance, which is longer than the first distance, the integration unit 72 generates an xy integrated reflection signal (an example of an integrated reflection signal) using the second reflection signal multiplied by a second coefficient smaller than the first coefficient. The second reflection signal multiplied by the second coefficient is a signal value obtained by multiplying the measured value (intensity) of the second reflection signal by a predetermined second coefficient. With this weighting, when a defect near the center affects the magnitude of the reflection signal, the xy integrated reflection signal can be generated while appropriately taking that effect into account.

[0056] Weighted addition can be performed based on the following equation (1). Equation (1) is a function that integrates over the range of real numbers m and n, from -1 to 1.

[0057]

number

[0058] In equation (1), I xy (t) is the intensity of the integrated reflected signal at coordinate (x,y) at time t. I x+m,y+n This refers to the intensity of the reflected signal at coordinates (x+m,y+n) of a measurement point (for example, the second irradiation positions P1~P8) located near the coordinates (x,y) of the measurement point of interest (for example, the first irradiation position P0), k(m,n) is a weighting coefficient (first coefficient, second coefficient, etc.) corresponding to the distance from the measurement point of interest. That is the case. (The coordinates of the measurement point of interest (P0) are (x, y), the coordinates of the neighboring measurement points (P1~P8) are (x+m, y+n), and the ranges of m and n are -1≦m and n≦1, respectively.)

[0059] The acquisition range of the reflected signal group, the shape of the acquisition area, and the weighting coefficient k(m,n) can be appropriately set according to the beam diameter of the ultrasonic beam and the intensity distribution of the ultrasonic beam. For example, if the intensity distribution of the ultrasonic beam follows a Gaussian distribution, it is preferable that the weighting coefficient k(m,n) also has a Gaussian distribution shape. Alternatively, as shown in Figure 10 above, the reflected signal group may be acquired by focusing on, for example, eight adjacent measurement points, and the weights of all second reflected signals constituting the reflected signal group may be made equal (k(m,n)=1.0), as described in detail in the second embodiment below. In this case, since weighting addition according to distance is not performed, the integrated reflected signal will be generated in accordance with the method described in Patent Document 1 above.

[0060] Figure 14 is a graph showing the first reflected signal and multiple second reflected signals (group of reflected signals) superimposed before phase correction. In other words, Figure 14 is a graph of the first and second reflected signals before step S601 described above. As shown in step S601 described above, the shift on the time axis (horizontal axis) of the peak (local peak) in section C is calculated for the first reflected signal (e.g., echo at the junction interface). Then, the phase of each of the group of reflected signals is corrected based on the calculated shift.

[0061] Figure 15 is a graph showing the first reflected signal and multiple second reflected signals (group of reflected signals) superimposed after phase correction. In other words, Figure 15 is a graph of the first reflected signal and the second reflected signals after steps S601 and S602 described above. Due to phase correction, as shown in Figure 15, the peaks (local peaks) in section D coincide on the time axis.

[0062] Figure 16 is a graph showing the integrated xy reflection signal obtained after phase correction and weighted addition. The graph shown in Figure 16 is obtained by going through step S603 described above. The peak in section E corresponds to the peaks in sections C and D (integrated peaks obtained by superimposing the first reflection signal and the second reflection signal). By using the graph shown in Figure 16 (signal intensity over time), the presence of defects can be determined using the integrated reflection signal obtained by integrating multiple reflection signals.

[0063] Returning to Figure 9, in the example of this disclosure, the integration unit 72 further integrates a predetermined range of reception time from the xy integrated reflection signal (an example of an integrated reflection signal) (integrating the signal of the xy integrated reflection signal for a predetermined reception time). This makes it possible to detect even smaller defects and further improve detection accuracy. In the example of this disclosure, the predetermined range of reception time is the z direction, which is the direction of the horizontal axis (time axis t) in Figure 16. Based on this, the integration unit 72 calculates the xyz integrated intensity value (step S104). That is, in the example of this disclosure, the presence of a defect is determined using the xy integrated reflection signal, but more specifically, the presence of a defect is determined based on the xyz integrated intensity value obtained using the xy integrated reflection signal.

[0064] In Figure 12 above, the integration unit 72 sets a range Tw (a predetermined time range) to be integrated in the time axis direction in the xy integrated reflection signal (step S604). The range Tw is like an imaging gate in an ultrasound examination device, for example. Conventionally, the maximum intensity within the imaging gate (time range Tw) was searched for, and the maximum intensity was converted into a pixel value, and the resulting pixel value was used to create an image. On the other hand, in the example of this disclosure, the signal intensity in the time range Tw is integrated, and the integrated intensity is converted into a pixel value, and the resulting pixel value can be used to create an image.

[0065] The xy integrated reflected signal has positive and negative values, as shown in Figure 16 above. Therefore, the integration unit 72 converts the xy integrated reflected signal within the integration time range Tw (Figure 17) into an absolute value (step S604). This allows the sum of the areas in the graph to be calculated when the signals are integrated (i.e., integrated). The integration unit 72 then further integrates the signal intensity within a predetermined range Tw of reception time from the generated xy integrated reflected signal with the generated xy integrated reflected signal. This allows the presence of defects to be determined taking time into account. In the example of this disclosure, the integration unit 72 adds all positive signals within the range Tw according to the following equation (2) (step S606). This calculates C(x,y), which represents the xyz integrated intensity value at the measurement point coordinates (x,y).

[0066]

number

[0067] In equation (2), st is the start time of range Tw, and et is the end time of range Tw.

[0068] In equation (2), all signals within range Tw are added together with uniform weights to calculate the integrated intensity value. However, for example, the maximum intensity within range Tw may be identified, and the values ​​obtained by adding them together with weights within a fixed time before and after the maximum intensity, i.e., the convolution integral value obtained by weighted addition, may be used as the xyz integrated intensity value. In either calculation method, the xy integrated reflected signal values ​​can be integrated in the time axis direction within a specific gate to calculate the xyz integrated intensity value.

[0069] The integration range Tw is a parameter predetermined based on the duration (pulse width) of a single wave, which varies depending on the specifications of probe 2. If Tw=1, integration in the time direction does not occur. Therefore, the integration unit 72 determines the range Tw, which is a predetermined range of reception time, based on the duration of the irradiated ultrasound, and generates an integrated reflected signal within the determined Tw. In this way, integration can be performed under conditions that conform to the specifications of probe 2.

[0070] As described above, in the first embodiment, the integration unit 72 first integrates the first reflection signal and the second reflection signal in the xy direction, which indicate the direction of ultrasonic irradiation, to generate an xy integrated reflection signal. Furthermore, the integration unit 72 further integrates the signal intensity within a predetermined range Tw of the reception time from the generated xy integrated reflection signal with the generated xy integrated reflection signal. This enables the generation of an xyz integrated reflection signal, and the pixel values ​​used for imaging the inspection target surface (bonding interface) can be calculated from the integrated intensity values.

[0071] In the flow shown in Figure 9, the image generation unit 73 uses the pixel value determined from the signal intensity of the integrated xy reflection signal as the pixel value of the first irradiation position P0, and generates an inspection image 95 from this pixel value (step S105). This allows the inspection image to be displayed on a display device such as the output device 8, or transmitted to any server. For example, if the image generation unit 73 is generating an 8-bit inspection image 95, it converts the distribution of integrated xyz intensity values ​​to a range of 0 to 255.

[0072] In the example of this disclosure, the pixel values ​​used in step S105 are values ​​based on xyz intensity values ​​determined from the signal intensity of the xy integrated reflection signal. If integration is not performed in the time range Tw, i.e., if step S104 is not performed, the inspection image 95 may be generated from pixel values ​​directly determined from the signal intensity of the xy integrated reflection signal generated in step S103.

[0073] By performing steps S101 to S105 shown in Figure 9 for all measurement points in the inspection area, an inspection image can be generated.

[0074] Figure 17 shows the overall process performed in the first embodiment. Ultrasound is irradiated onto the inspection area 90 (xy plane) of the object to be inspected, with the probe 2 scanning from the upper left to the lower right, at a predetermined scanning pitch. As a result, reflected waves from the object to be inspected 5 are received, and reflected signals from the inspection surface (e.g., bonding interface) are obtained from each point of interest measurement point (first irradiation position P0) within the inspection area 90. Two reflected signals are obtained: the first is the reflected signal 91 of the point of interest measurement point (including the reflected signal 91a on the inspection surface), and the second is the group of reflected signals 92 of measurement points within the ultrasonic beam diameter (in this case, 8 nearby measurement points). Then, by integrating the reflected signal 91 and the group of reflected signals 92, a graph 93 of the xy integrated reflected signal is generated.

[0075] Furthermore, as shown in Graph 94, the integrated reflected signal C(t) is calculated by integrating the reflected signals in the range Tw(st~et) in Graph 93 of the integrated xy reflected signal. The integrated reflected signal C(t) is the formula that forms the basis of the above-mentioned integrated xyz signal value, and the integrated intensity value I of xyz is derived from the integrated reflected signal C(t). xyz The following is calculated: xyz integrated intensity value I xyz This is converted to a value such as 8 bits, and the converted value is taken as the pixel value of the measurement point 96 (first irradiation position P0).

[0076] By performing the above process for all measurement points, an inspection image 95 is generated. The generated inspection image 95 is input to the defect detection unit 74, where a defect determination is performed and defects are detected.

[0077] In the first embodiment described above, the time-axis processing shown in step S104 is performed. However, in the second embodiment, the time-axis processing shown in step S104 is not performed. Therefore, the inspection image 95 is generated from the xy integrated reflection signal. For example, in the time range st~et of the xy integrated reflection signal in Figure 17, the intensity of the maximum negative peak I xy This is converted to the pixel value of the measurement point of interest, as shown by the dashed line in the figure. However, depending on the characteristics and specifications of probe 2, a positive peak may be used instead of a negative peak.

[0078] Whether or not to perform integration in the time axis direction, that is, whether to perform control according to the first embodiment or control according to the second embodiment, can be fixed to one or the other in advance, depending on the functions and specifications of the ultrasonic inspection device 100. However, for example, the ultrasonic inspection device 100 (especially the control device 7) may be designed so that the control of the first embodiment and the control of the second embodiment can be arbitrarily selected and executed, and either one can be selected and executed according to the user's request (selection). For example, if the control of the first embodiment is performed, integration in the time axis direction is also performed, so the accuracy of defect detection can be further improved. On the other hand, if the control of the second embodiment is performed, integration in the time axis direction is not performed, so the calculation time can be shortened and the inspection time can be shortened.

[0079] In the third embodiment, the integration in the xy direction and the integration in the z direction (time direction) are reversed compared to the first embodiment. That is, in the third embodiment, the integration unit 72 generates a first integrated signal by integrating the reflected signals within a predetermined range Tw of the first reflected signal in the xy direction, which is within a predetermined range of reception time. At the same time, the integration unit 72 generates a second integrated signal by integrating the reflected signals within the same predetermined range Tw of the second reflected signal in the xy direction, which is within a predetermined range of reception time. Furthermore, the integration unit 72 integrates the first integrated signal and the second integrated signal. Even in this way, an inspection image 95 can be generated.

[0080] Specifically, the integration unit 72 aligns the phases of the first reflected signal and the group of reflected signals (multiple second reflected signals) along the time axis. Then, for each of the phase-aligned group of reflected signals, the integration unit 72 calculates a group of z-integrated intensity values ​​by integrating the signals within the range Tw. Furthermore, the integration unit 72 weights and adds the z-integrated intensity values ​​of measurement points adjacent to the first irradiation position P0 (the second irradiation positions P1 to P8 from which the second reflected signals are acquired) according to their distance from the first measurement point (first irradiation position P0). The obtained xyz combined intensity values ​​are converted into pixel values ​​of the first measurement point to generate the inspection image 95.

[0081] Figure 18 is a flowchart of the ultrasound inspection method in the third embodiment. The first reflected signal and the group of reflected signals are acquired in the same manner as in steps S101 and S102 described above. Next, the integration unit 72 integrates the reflected signals within the range Tw in the time axis direction (z direction) for each of the first reflected signal and the group of reflected signals to generate a z-integrated reflected signal group (S1003). The specific integration method in the time axis direction can be the method described in the first embodiment described above. Next, the integration unit 72 calculates a group of z-integrated intensity values ​​(step S1004). Step S1004 will be described with reference to Figure 19.

[0082] Figure 19 shows the overall process performed in the third embodiment. When ultrasound is irradiated onto the inspection area 90 and the reflection is received in the same manner as in the first embodiment, a graph 111 is obtained by superimposing the reflection signals from the measurement point of interest (first irradiation position P0) and, for example, eight adjacent nearby measurement points (second irradiation positions P1 to P8). Of these, for example, by performing a convolution integral over the range Tw on any three reflection signals, the z-integrated reflection signal group (I) shown in graph 112 is obtained. z (t)) is obtained.

[0083] The start time st of the range Tw is different for each individual. In the example of this disclosure, the z-integrated intensity value is calculated from each z-integrated reflected signal (step S1004). These calculated z-integrated intensity values ​​are collectively called the z-integrated intensity value group. As an example of the method for calculating the z-integrated intensity value, each I shown in Graph 112 z(t) maximum intensity (C Z1 、C Z2 、C Z3 ) can be used. Also, as another example, the sum of I z (t) can be used.

[0084] Returning to FIG. 18, next, for the z-integrated intensity value group (C Z1 、C Z2 、C Z3 ···), weights are assigned according to the distance from the target measurement point (the first irradiation position P0). Specifically, for example, similar to the first embodiment, the weights decrease as the distance from the center increases. Then, by performing weighted addition in the same manner as in the first embodiment, the xyz-integrated intensity value C(x, y) at the measurement point coordinates (x, y) is calculated (step S1005). Step S1005 is an integration step for generating an xyz-integrated reflection signal (an example of an integrated reflection signal) by integrating the first reflection signal integrated in the time axis direction in advance and the second reflection signal (reflection signal group) also integrated in the time axis direction in advance. Next, in the same manner as in the first embodiment, the xyz-integrated intensity value C(x, y) is converted into a pixel value, and the inspection image 95 is generated (step S1006).

[0085] In the third embodiment, first, the integrated intensity values of each reflection signal group in the time axis direction are uniquely calculated within Tw. Therefore, there is an advantage that the phase alignment of each reflected wave does not need to be performed.

Explanation of Reference Numerals

[0086] 1 Detection unit 10 Cartesian coordinate system 100 Ultrasonic inspection device 13 Scanning measurement device 2 Probe 3 Detector 4 Reflected wave 5 Inspection object 7 Control device 71 Acquisition unit 72 Integration unit 73 Image generation unit 74 Defect detection unit 75 Output unit 76 Parameter setting section 77 Databases 8 Output device

Claims

1. A control device for controlling an ultrasonic inspection apparatus that performs ultrasonic inspection of an object to be inspected by irradiating it with ultrasound and receiving reflected waves, An acquisition unit that acquires a first reflected signal received from a first irradiation position of the ultrasonic waves on the object to be inspected, and a second reflected signal received from a second irradiation position of the ultrasonic waves on the object to be inspected, wherein the distance from the first irradiation position is shorter than the beam diameter of the ultrasonic waves on the surface of the object to be inspected. The system includes an integration unit that integrates the first reflected signal and the second reflected signal to generate an integrated reflected signal. A control device characterized by the following features.

2. In the control device according to claim 1, The integration unit generates the integrated reflected signal by aligning the phase of the first reflected signal with the phase of the second reflected signal. A control device characterized by the following features.

3. In the control device according to claim 2, The integration unit further integrates a predetermined range of reception time from the integrated reflected signal. A control device characterized by the following features.

4. In the control device according to claim 1, The integration unit generates an xy integrated reflection signal as the integrated reflection signal by integrating the first reflection signal and the second reflection signal in the xy direction, which indicate the irradiation direction of the ultrasonic waves. Furthermore, the integration unit further integrates the signal intensity within a predetermined range of reception time from the generated xy integrated reflected signal with respect to the generated xy integrated reflected signal. A control device characterized by the following features.

5. In the control device according to claim 1, The integration unit generates a first integrated signal by integrating the first reflected signals in the x and y directions within a predetermined range of reception time, and generates a second integrated signal by integrating the second reflected signals in the x and y directions within the predetermined range of reception time. Furthermore, the integration unit integrates the first integrated signal and the second integrated signal. A control device characterized by the following features.

6. In the control device according to claim 1, The system includes an image generation unit that generates an inspection image from pixel values ​​determined from the signal intensity of the integrated reflection signal. A control device characterized by the following features.

7. In the control device according to claim 1, The integration unit generates the integrated reflection signal using the second reflection signal weighted according to the distance. A control device characterized by the following features.

8. In the control device according to claim 7, The aforementioned integration unit is When the aforementioned distance is the first distance, the second reflected signal multiplied by the first coefficient is used. When the aforementioned distance is a second distance which is longer than the first distance, the second reflected signal multiplied by a second coefficient which is smaller than the first coefficient is used. The integrated reflected signal is generated A control device characterized by the following features.

9. A control device according to claim 1, The integration unit determines a predetermined range of reception time based on the duration of the irradiated ultrasonic waves, and generates the integrated reflected signal within the predetermined range of reception time. A control device characterized by the following features.

10. A control device according to claim 1, The first and second irradiation positions are located within the irradiation range of the same ultrasonic beam. A control device characterized by the following features.

11. A control device according to claim 10, Multiple second irradiation positions are arranged. A control device characterized by the following features.

12. The control device according to claim 1, A probe for irradiating the ultrasonic waves and receiving the reflected waves, The device comprises a scanning measuring device that drives the probe in the x and y directions. An ultrasonic inspection device characterized by the following features.

13. An ultrasonic inspection method for inspecting an object by irradiating it with ultrasound and receiving reflected waves, An acquisition step of acquiring a first reflected signal received from a first irradiation position of the ultrasonic waves on the object to be inspected, and a second reflected signal received from a second irradiation position of the ultrasonic waves on the object to be inspected, wherein the distance from the first irradiation position to the object to be inspected is shorter than the beam diameter of the ultrasonic waves on the surface of the object to be inspected. The process includes an integration step of integrating the first reflected signal and the second reflected signal to generate an integrated reflected signal. An ultrasound examination method characterized by the following features.

Images