TW201623958A - Ultrasonic imaging device and observation method using the same - Google Patents

Abstract

To observe specimens having depth and curved surface or inclination defect structures is observed with high resolution. An ultrasonic imaging device (1) comprising an ultrasonic detection part (2) capable of switching focal depth, an X-axis driver (81) and a Y-axis driver (82) enabling the ultrasonic detection part (2) to scan in the planar direction; an Z-axis driver (83) for adjusting the interval between the ultrasonic detection part (2) and a specimen (4); and a depth mapping (53) performing scanning by setting the ultrasonic detection part (2) focal depth to be broad, and a scan control part (51) setting the ultrasonic detection part (2) focal depth narrow, and making the focal depth of the ultrasonic detection part (2) include the observation position, so as to allow adjustment of the distance between the ultrasonic detection part (2) and the observation position while using the ultrasonic detection part (2) to perform scanning.

Description

Ultrasonic imaging device and observation method using the same

The present invention relates to an ultrasonic imaging apparatus that images holes, peeling, or the like inside a semiconductor or an electronic component or the like, and an observation method using the same.

Conventionally, in order to investigate the distribution of holes or delaminations such as defects in semiconductors or integrated circuits by ultrasonic waves, one ultrasonic sensor is mechanically scanned and imaged in the horizontal direction. The method. In this inspection method, ultrasonic waves are transmitted and received with the focus of the inspection target portion in the structure of the inspection object by an ultrasonic sensor, and the echoes reflected from the inspection target portion (ultrasonic waves) The gate is processed to obtain the intensity information or time information of the echo. By mapping the obtained echo information in the horizontal quadratic space, it is possible to generate inspection image information, and investigate the distribution of defects based on the inspection image information.

Patent Document 1 describes an invention of a single-channel scanning type ultrasonic microscope which increases the processing amount of an acoustic imaging system by connecting a plurality of sensing units in parallel in a single-channel electronic circuit. By constructing this, To increase the throughput of the sonic imaging system.

[Previous Technical Literature] [Patent Document]

[Patent Document 1] US Patent Application Publication No. 2014/0116143

With the miniaturization of semiconductors or electronic parts in recent years, inspection of image information requires high resolution. In order to achieve high resolution, the ultrasonic imaging apparatus uses a high-decomposition energy probe (high resolution probe) having a high frequency of ultrasonic waves.

The high-decomposition energy probe has a large attenuation of the ultrasonic wave, and the focal depth and the movable region of the tracking gate are narrow. Here, the depth of focus is from the surface position on the side of the ultrasonic wave of the irradiation probe, and the focus can be connected to the distance in the irradiation direction of the ultrasonic wave. This narrow depth of focus poses a problem for the bending or tilting of the sample or defect structure.

That is, if the surface or internal defect structure of the sample is bent or tilted little, a method of tracking the gate is made with respect to the specific reflected echo received by the probe. However, if the surface or internal defect structure of the sample has a large curvature or inclination, and the focus depth of the probe of the high decomposition energy is deviated, the focus cannot be connected even if the gate is traced. Accordingly, it is difficult to observe the sample by scanning the probe in the horizontal direction.

Fig. 11 is a waveform diagram of the surface echo of the sample 4 of the high-resolution probe of the comparative example. The vertical axis of the graph represents the voltage applied to the probe, respectively. The horizontal axis of the graph represents the timing based on the transmitted pulse. In this comparative example, the case where the surface of the sample was inclined was large.

Each curve represents a case where only a specific distance is scanned at a time, and a high-resolution probe is applied with a pulse signal to receive a reflected waveform of its pulse signal.

The first curve shown at the uppermost portion indicates a case where the received signal does not pulse during the gate period Tg. At this time, the surface of the sample is very close to the high resolution probe, and thus is outside the range of the depth of focus.

Next, the second graph shows a case where the reception signal is pulsed only during the gate period Tg. At this point, the surface of the sample is located away from the high resolution probe and is close to the depth of focus.

The third curve shows the case where the reception signal of the Tg during the gate period is markedly pulsed. The pulse occurs after the pulse from the transmitted signal to the time Tc. At this time, the surface of the sample is in the range of the depth of focus of the high resolution probe.

Next, the fourth curve shown shows the case where the reception signal is pulsed only during the gate period Tg. At this time, the surface of the sample is further away from the high resolution probe and deviates from the range of the depth of focus.

The fifth curve shown at the lowermost portion indicates a case where the received signal does not pulse during the gate period Tg. At this point, the surface of the sample is further away from the high resolution probe, outside the range of depth of focus.

As shown in Fig. 11, when the inclination of the surface of the sample is large, even if the gate is traced, the focus cannot be connected, and thus the surface or internal defect cannot be observed. Trapped.

On the other hand, the probe with a long focal length is smaller than the probe with high resolution energy, the attenuation of the ultrasonic wave is small, and the depth of focus and the movable region of the tracking gate are wide. However, in the probe with a long focal length, there is a problem that the sample cannot be observed with high decomposition energy.

Therefore, it is considered to switch between the probe for scanning the long focal length and the probe for the high resolution energy. In the prior art, the main purpose of scanning with a plurality of probes is to increase the throughput as in the invention described in Patent Document 1, and to switch the probes for the purpose of matching.

Accordingly, an object of the present invention is to provide an ultrasonic imaging apparatus capable of observing a sample having a deep and curved surface or a tilted defect structure with high decomposition energy, and an observation method using the same.

In order to solve the above problems, the ultrasonic imaging apparatus of the present invention includes: an ultrasonic detecting means capable of switching between a resolution energy and a wide depth of focus; and a scanning means for scanning the ultrasonic detecting means in a planar direction; And a control means for adjusting the interval between the ultrasonic detecting means and the sample; and the controlling means for setting the depth of the depth of focus to the first focus by setting the decomposition energy of the ultrasonic detecting means to the first decomposition energy The depth is mapped by the scanning means to obtain a depth map of the observation position of the sample, and the decomposition of the ultrasonic detecting means can be set to a second decomposition energy higher than the first decomposition energy, and the width of the depth of focus is set to be larger. The second focus of the first focus depth is narrow The depth is such that the second focus depth of the ultrasonic detecting means includes the observation position related to the depth map, and the distance between the ultrasonic detecting means and the observation position can be adjusted by the depth adjusting means. The ultrasonic detecting means is scanned by the scanning means.

The observation method using the ultrasonic imaging apparatus of the present invention includes: an ultrasonic sound detecting means capable of switching a wide range of decomposition energy and a depth of focus; and a scanning means for scanning the ultrasonic detecting means in a planar direction; the depth is adjustable Means for adjusting the interval between the ultrasonic detecting means and the sample; and the controlling means, wherein the monitoring method using the ultrasonic imaging device is characterized in that the control means sets the decomposition energy of the ultrasonic detecting means to the first decomposition energy a step of setting a width of the depth of focus to a first depth of focus; a step of scanning the ultrasonic detecting means in a planar direction by the scanning means; and a step of obtaining a depth map of the observed position of the sample by the control means; The control means sets the ultrasonic detecting means to a second decomposition energy higher than the first decomposition energy, and sets a width of the focus depth to a second focus depth which is narrower than the first focus depth; and the ultrasonic wave The second focus depth of the detecting means includes an upper depth map In the manner of observing the position, the ultrasonic detecting means scans the ultrasonic detecting means by the scanning means by adjusting the distance between the ultrasonic detecting means and the observation position by the depth adjusting means.

Other means are described in the form of implementing the invention.

According to the present invention, it is possible to provide an ultrasonic imaging apparatus capable of observing a sample having a deep and curved surface or a tilted defect structure with high resolution, and an observation method using the same.

1‧‧‧Ultrasonic imaging device

2‧‧‧Supersonic detection unit (ultrasonic detection means)

21‧‧‧Encoder

22‧‧‧Long focus distance probe

221‧‧‧Piezoelectric components

23‧‧‧High resolution probe

231‧‧‧Piezoelectric components

24‧‧‧ switch

3‧‧‧Sink

31‧‧‧ water

4‧‧‧ samples (observation position)

41‧‧‧ Internal defect structure (observation position)

5‧‧‧Image processing display device

51‧‧‧Scan Control Department

52‧‧‧Time Control Department

53‧‧‧Deep mapping

54‧‧‧Portrait Generation Department

6‧‧‧ Signal generation measuring device

61, 62‧‧‧ pulse wave transmitter

64‧‧‧Amplifier

65‧‧‧A/D conversion department

66‧‧‧Signal Processing Department

7‧‧‧Control device (control means)

81‧‧‧X-axis drive (scanning means)

82‧‧‧Y-axis drive (scanning means)

83‧‧‧Z-axis drive (depth adjustable means)

Fig. 1 is a schematic block diagram showing an ultrasonic imaging apparatus in the present embodiment.

Fig. 2 is a perspective view showing a scanning method of the ultrasonic imaging apparatus.

Fig. 3 is a conceptual diagram showing scanning by a long focal length probe.

4 is a conceptual diagram showing the present scan by a high resolution probe.

Fig. 5 is a waveform diagram of surface echoes of a sample by a long focal length probe.

Fig. 6 is a waveform diagram of surface echoes of a sample by a high resolution probe.

Fig. 7 is a view showing an observation operation of a sample having an inclined internal defect structure.

Fig. 8 is a view showing a detecting operation of a sample having an inclined internal defect structure.

Fig. 9 is a flow chart showing the observation processing by the ultrasonic imaging apparatus.

Figure 10 is a diagram showing a depth map.

Figure 11 is a surface echo of a sample of a high resolution probe of Comparative Example Waveform.

Hereinafter, the form for carrying out the invention will be described in detail with reference to the drawings.

Fig. 1 is a schematic configuration diagram showing an ultrasonic imaging apparatus 1 in the present embodiment.

The ultrasonic imaging apparatus 1 of the present embodiment acquires the depth map 53 relating to the observation position of the sample 4 by the ultrasonic detecting unit 2 that can switch the depth of focus. In the present embodiment, the signal generation measuring device 6 includes pulse wave transmitters 61 and 62, and the ultrasonic wave detecting unit 2 includes a long focal length probe 22 and a high resolution probe 23. By switching the long focal length probe 22 and the high resolution probe 23 with the switch 24, the depth of focus of the ultrasonic contact portion 2 can be switched.

The ultrasonic imaging apparatus 1 is provided with an ultrasonic detecting unit 2 that performs transmission and reception of ultrasonic waves, and an imaging processing display device 5 that displays ultrasonic imaging by controlling the ultrasonic imaging device 1 and between the ultrasonic detecting unit 2 and the ultrasonic detecting unit 2 A signal generating measuring device 6 for inputting and outputting electrical signals is performed. The ultrasonic imaging apparatus 1 further includes an X-axis driving device 81 and a Y-axis driving device 82 that planarly scan the ultrasonic detecting unit 2, and a Z-axis driving device 83 that can adjust the interval between the ultrasonic detecting unit 2 and the sample 4. And control the control device 7.

The ultrasonic detecting unit 2 has a long focal length probe 22 that sets the relative spatial coordinate positions of each other, and a high resolution probe 23. The The long focal length probe 22 and the high resolution probe 23 are supported by the ultrasonic contact portion 2, and are immersed in the water 31 filled with the water tank 3, and the piezoelectric elements 221 and 231 are disposed to face the sample 4. Further, the ultrasonic detecting unit 2 further includes an encoder 21 and a switch 24 that detect the scanning position of the ultrasonic detecting unit 2.

The long focus distance probe 22 is provided with a piezoelectric element 221 that converts electrical signals and ultrasonic signals. The long focal length probe 22 has a wide focal depth (first focal depth), and the frequency of the ultrasonic waves is relatively low, and the decomposition energy is low.

The high resolution probe 23 is provided with a piezoelectric element 231 that converts electrical signals and ultrasonic signals. The frequency of the ultrasonic wave generated by the piezoelectric element 231 is higher than the frequency of the ultrasonic wave generated by the piezoelectric element 221 . The high resolution probe 23 is for high resolution, the frequency of the ultrasonic wave is relatively high, and the depth of focus (second depth of focus) is narrow.

The switch 24 switches any of the piezoelectric elements 221 and 231 to output to the A/D converter 65 based on the output signal of the timing control unit 52.

The imaging processing display device 5 includes a scan control unit 51 that controls the scanning position of the ultrasonic detecting unit 2, a timing control unit 52 that controls the transmission and reception timing of the ultrasonic waves, and an image generating unit 54 that generates an ultrasonic image, and observes the sample 4 The depth map 53 of the mapping of the depth information related to the position is stored in the memory unit (not shown).

The signal generation measuring device 6 includes pulse wave transmitters 61 and 62 that generate electrical signals of pulse waves, an amplifier 64 that amplifies the received signals received by the ultrasonic detecting unit 2, and converts the received signals from analog signals. The A/D converter 65 is replaced with a digital signal, and the signal processing unit 66 that performs signal processing on the received signal. Further, even if one pulse wave transmitter is provided, it is possible to switch to one of the two probes by switching or the like instead of the two pulse wave transmitters 61 and 62.

The scan control unit 51 is connected to the control device 7 (scanner) so as to be able to input and output. The scan control unit 51 controls the scanning position of the ultrasonic detecting unit 2 in the horizontal direction by the control device 7, the X-axis driving device 81, and the Y-axis driving device 82 (scanning means), and receives the ultrasonic detecting portion from the control device 7. 2 current scan location information. Further, the scan control unit 51 controls the distance between the ultrasonic detecting unit 2 and the sample 4 by the Z-axis driving device 83 (depth adjustable means), and receives the current Z-axis position information of the ultrasonic detecting unit 2 from the control device 7. .

The output side of the control device 7 is connected to the X-axis driving device 81, the Y-axis driving device 82, and the Z-axis driving device 83. The control device 7 is connected to the output side of the encoder 21 of the ultrasonic detecting unit 2. The control device 7 detects the scanning position of the ultrasonic detecting unit 2 by the output signal of the encoder 21, and controls the ultrasonic detecting unit 2 to be the instructed scanning position by the X-axis driving device 81 and the Y-axis driving device 82. .

The control device 7 detects the distance between the ultrasonic detecting unit 2 and the sample 4 by the output signal of the encoder 21, and causes the ultrasonic detecting unit 2 to be the indicated depth position by the Z-axis driving device 83. Take control.

The control device 7 receives the control instruction of the ultrasonic detecting unit 2 from the scan control unit 51, and responds to the scanning position information of the ultrasonic detecting unit 2 and Depth location information.

The timing control unit 52 outputs the ultrasonic transmission/reception timing signal (information) to the signal generation measuring device 6 based on the scanning position information of the ultrasonic contact unit 2 acquired from the scanning control unit 51.

The pulse wave transmitter 61 outputs a pulse wave to the piezoelectric element 221 of the long focal length probe 22 based on the timing signal output from the timing control unit 52.

The pulse wave transmitter 62 outputs a pulse wave to the piezoelectric element 231 of the high-resolution probe 23 based on the timing signal output from the timing control unit 52.

The piezoelectric elements 221 and 231 are each provided with electrodes on both sides of the piezoelectric film. The piezoelectric elements 221 and 231 transmit ultrasonic waves from the piezoelectric film by applying a voltage between the electrodes. The frequency of the ultrasonic wave transmitted from the piezoelectric element 221 is lower than the frequency of the ultrasonic wave transmitted from the piezoelectric element 231.

Further, the piezoelectric elements 221 and 231 convert the echo (received wave) received by the piezoelectric film into a reception signal which is a voltage generated between the electrodes. The switch 24 selects one of the reception signal of the piezoelectric element 221 and the reception signal of the piezoelectric element 231 to output. The amplifier 64 amplifies the selected received signal and outputs it as an output signal. The A/D converter 65 converts the amplified received signal from an analog signal to a digital signal.

The signal processing unit 66 is a signal processor for receiving signals. The signal processing unit 66 cuts out only the specific period of the reception signal by the gate pulse output from the timing control unit 52. The signal processing unit 66 is to receive the amplitude information of the received signal for a specific period or the received signal for a specific period. The time information is output to the image generating unit 54.

The image generating unit 54 generates an ultrasonic image at a specific frequency based on the output signal of the signal processing unit 66.

In the observation of the sample 4 by the ultrasonic imaging apparatus 1, first, before the long focal length distance probe 22 is used, the curved or inclined spatial coordinates of the sample 4 or the defect structure are roughly investigated. Next, the ultrasonic imaging apparatus 1 performs the scanning using the high resolution probe 23 based on the information of the depth map 53 thereof. At this time, the ultrasonic imaging apparatus 1 is mechanically adjusted not only in the horizontal direction but also in the vertical direction (Z-axis direction). According to this, even if the object is deeply bent or inclined, the focus of the high-resolution probe 23 can be aligned, and the sample 4 can be observed with high decomposition.

The scan density of the depth map 53 is sparse in this scan. Accordingly, when acquiring the scanning position in the horizontal direction of the scanning, the scanning control unit 51 regards the depth information of the nearest neighbor position as the observation position. Furthermore, even if the complex depth information of the nearest neighbor is interpolated, the depth information of the scanning position can be calculated.

FIG. 2 is a perspective view showing a scanning method of the ultrasonic imaging apparatus 1.

Here, as a part of the ultrasonic imaging apparatus 1, only the X-axis driving device 81, the Y-axis driving device 82, the Z-axis driving device 83, the ultrasonic detecting portion 2, and the water tank 3 are shown.

The X-axis driving device 81 moves the Y-axis driving device 82, the Z-axis driving device 83, and the ultrasonic detecting portion 2 in the ±X direction. The Y-axis driving device 82 moves the Z-axis driving device 83 and the ultrasonic detecting unit 2 in the ±Y direction. The Z-axis driving device 83 moves the ultrasonic detecting unit 2 in the ±Z direction.

The ultrasonic detecting unit 2 mounts the long focal length probe 22 and the high resolution probe 23 in an alternative manner, and has an encoder 21 (Fig. 1). The ultrasonic detecting unit 2 is immersed in the water 31 filled in the water tank 3, and is disposed so as to face each other with a specific distance in the Z direction of the upper portion of the sample 4.

FIG. 3 is a conceptual diagram showing scanning by the long focal length probe 22 before. Here, an operation of scanning by the ultrasonic imaging apparatus 1 will be described with reference to FIGS. 1 and 2.

The sample 4 is, for example, a disk-shaped silicon wafer, and the center portion is bent downward. In Fig. 3, a plan view and a side view of the sample 4 are shown. The scanning control unit 51 causes the ultrasonic detecting unit 2 to scan in the ±Y direction, and acquires a line of pixels corresponding to the sample 4 by the long focal length probe 22. The focal length 222 of the long focal length distance probe 22 is broad and can be scanned by including the curved sample 4.

When detecting that the ultrasonic detecting unit 2 is located at one end (the right end of the figure) in the Y direction, the scanning control unit 51 causes the ultrasonic detecting unit 2 to scan only in the +X direction and then scan in the +Y direction to obtain one line amount. portrait. after that. After the ultrasonic detecting unit 2 moves only a certain pitch in the −X direction, scanning is performed in the −Y direction to obtain an image of one line. This operation is repeated, and the scan control unit 51 performs scanning of a specific range. The scanning control unit 51 fixes the depth direction (Z-axis direction) of the long focal length probe 22 in the scanning of the planar direction of the long focal length probe 22 . Accordingly, when scanning is performed while the depth direction is adjustable, the scanning can be performed at a higher speed.

The amount of movement in the -X direction in the pre-scan is thicker than the scan, for example, in the conceptual diagrams shown in FIGS. 3 and 4, the amount of movement in the -X direction in this scan is three times. That is, one line in the front scan corresponds to the three lines in the scan shown in FIG. In this way, by making the front scan perform a thicker scan than the current scan, the pre-scan can be completed in a shorter time than the current scan.

The timing control unit 52 of the imaging processing display device 5 receives the scanning position information of the ultrasonic detecting unit 2 in the X direction and the Y direction from the scanning control unit 51, and instructs the signal generation measuring device 6 to superate based on the scanning position information in the X direction. The sound wave is sent, and a gate pulse for signal processing of the received signal is output.

The signal generation measuring device 6 outputs the pulse wave signal output from the pulse wave transmitter 61 to the long focus distance probe 22 of the ultrasonic wave detecting unit 2. Further, the signal generation measuring device 6 amplifies the reception signal of the echo (received wave) of the long focal length probe 22 of the ultrasonic wave detecting portion 2 by the amplifier 64, and then converts it into a digital signal by the A/D converter 65. The signal processing unit 66 performs signal processing on the received signal (digital signal) based on the gate pulse input from the timing control unit 52, and outputs it to the imaging processing display device 5.

The imaging processing display device 5 creates a depth map 53 relating to the surface and internal defect structure of the sample 4 based on the information of the scan information acquired by the scan control unit 51 and the information of the received signal when the signal generation measuring device 6 performs signal processing. . Here, the surface and internal defect structure of the sample 4 is the observation position of the sample 4. The depth map 53 related to the observation position of the sample 4 is based on the information of the time at which the echo is received by the received signal. And generated.

FIG. 4 is a conceptual diagram showing the present scan by the high resolution probe 23. The scanning system is executed following the previous scanning shown in FIG. Here, the operation of the scanning by the ultrasonic imaging apparatus 1 will be described with reference to FIGS. 1 and 2.

The scanning control unit 51 obtains the observation position related to the depth map 53 so that the depth of focus 232 of the ultrasonic detecting unit 2 is such that the ultrasonic detecting unit 2 can scan in the +Y direction while being adjustable in the depth direction. 1 line of pixels. When the scanning control unit 51 detects that the ultrasonic detecting unit 2 is located at one end (the right end of the figure) in the +Y direction, the ultrasonic detecting unit 2 causes the ultrasonic detecting unit 2 to move in the depth direction after moving only a certain pitch in the −X direction. It can be adjusted while scanning in the -Y direction to obtain a 1-line image. This operation is repeated, and the scan control unit 51 performs the local scan of the specific range.

Further, in the present embodiment, the high-resolution probe 23 and the long-focus distance probe 22 differ only in the spatial coordinate positions opposed to each other. Accordingly, the scan control unit 51 first corrects the horizontal position associated with the high-resolution probe 23 only in the relative space coordinates. Next, the distance between the high-resolution probe 23 and the sample 4 can be adjusted such that the observation position of the depth map 53 related to the horizontal position thereof includes the depth of focus 232 of the high-resolution probe 23.

The timing control unit 52 and the scan control unit 51 of the imaging processing display device 5 pick up the scanning position information in the X direction and the Y direction from the ultrasonic detecting unit 2, and make the super sound based on the scanning position information and the depth map 53. The wave detecting unit 2 is adjustable in the depth direction (±Z direction). The timing control unit 52 instructs the signal generation measuring device 6 to transmit the ultrasonic wave based on the scanning position information in the Y direction, and outputs a gate pulse for performing signal processing on the received signal.

The signal generation measuring device 6 outputs the pulse wave signal output from the pulse wave transmitter 62 to the ultrasonic detecting unit 2. Further, the signal generation measuring device 6 amplifies the reception signal of the echo (received wave) of the high-resolution probe 23 of the ultrasonic detecting unit 2 by the amplifier 64, and then converts it into a digital signal by the A/D converter 65. The signal processing unit 66 performs signal processing on the received signal (digital signal) based on the gate pulse input from the timing control unit 52, and outputs it to the imaging processing display device 5.

The imaging processing display device 5 uses the information of the scanning position acquired by the scanning control unit 51 as the pixel position, and the information of the received signal that the signal generation measuring device 6 performs signal processing is used as the information of the brightness or color of the pixel. The internal structure of the sample 4 is visualized and displayed. It is indicated that the ultrasonic image inside the sample 4 may be based on the amplitude information of the received signal, even if it is based on the time when the received signal becomes a certain amplitude or more. Furthermore, even if the brightness information is mapped on the depth map 53, it can be displayed.

FIG. 5 is a waveform diagram of the surface echo of the sample 4 by the long focal length probe 22. The vertical axis of the graph represents the voltage applied to the long focus distance probe 22, respectively. The horizontal axis of the graph represents the timing based on the transmitted pulse. In this case, the case where the surface of the sample 4 is inclined is large.

Each curve indicates that the probe 22 is applied at the long focus distance in each scanning position. The transmission pulse is applied, and the ultrasonic wave is sent to the sample Z in the -Z direction, and the long focus distance probe 22 receives the reflected waveform of the pulse. From the first curve shown in the uppermost portion to the fifth curve shown in the lowermost portion, the scanning position is horizontally moved in order, and the position of the surface of the sample 4 becomes deep.

It is shown that in the uppermost first curve, the reception signal at the gate period Tg and the transmission pulse delay time T0 is pulsed. The surface of the sample 4 at this time is close to the long focal length distance probe 22, but is within the range of the focal depth of the long focal length distance probe 22. The imaging processing display device 5 calculates the depth information related to the scanning position by dividing the time T0 by the speed of sound in the medium and multiplying by 1/2.

In the second curve shown next, a pulse is generated in the gate period Tg and the reception signal delayed by the transmission pulse T1. The position of the surface of the sample 4 at this time is away from the long focal length distance probe 22 and is within the range of the focal depth of the long focal length distance probe 22.

In the third curve, a pulse is generated during the gate period Tg and the received signal of the transmission pulse delay time T2. The position of the surface of the sample 4 at this time is away from the long focal length distance probe 22 and is within the range of the focal depth of the long focal length distance probe 22.

In the fourth curve shown next, a pulse is generated in the gate period Tg and the received signal delayed by the transmission pulse T3. The position of the surface of the sample 4 at this time is away from the long focal length distance probe 22 and is within the range of the focal depth of the long focal length distance probe 22.

It is indicated that the fifth curve at the lowermost portion is in the gate period Tg and is pulsed from the reception signal of the transmission pulse delay time T4. Sample 4 at this time The surface is located away from the long focal distance probe 22 and is within the range of the focal depth of the long focal distance probe 22.

As shown in Fig. 5, even when the inclination of the surface of the sample 4 is large, the depth map 53 can be created by connecting the focus with the gate tracking in the range of the focal depth of the long focal length probe 22.

Fig. 6 is a waveform diagram of the surface echo of the sample 4 by the high-resolution probe 23. The vertical axis of the graph represents the voltage applied to the high resolution probe 23, respectively. The horizontal axis of the graph represents the timing based on the transmitted pulse. In this case, the case where the surface of the sample 4 is inclined is large.

Each curve indicates that a transmission pulse is applied to the high-resolution probe 23 at each scanning position, the ultrasonic wave is transmitted to the sample 4 in the -Z direction, and the high-resolution probe 23 receives the reflected waveform of the pulse. From the first curve shown at the uppermost portion to the fifth curve shown at the lowermost portion, the horizontal position sequentially moves horizontally, and the position of the surface becomes deep, and the high-resolution probe 23 moves in the depth direction (-Z direction).

The high-resolution probe 23 is adjustable in the depth direction in such a manner that its own depth of focus contains a surface. In other words, the scanning control unit 51 controls the Z-axis driving device 83 via the control device 7 such that the transmission pulse of the high-resolution probe 23 and the time interval of the reflected waveform of the pulse become close to the time Tc.

From the first curve shown in the uppermost portion to the fifth curve shown in the lowermost portion, a pulse is generated in the received signal after the gate period Tg and after the transmission pulse delay time Tc. At this time, the surface of the sample 4 is within the range of the depth of focus 232 of the high-resolution probe 23. This time Tc is from high resolution The distance from the front end of the probe 23 to the center of the depth of focus 232 is divided by the value of the speed of sound.

In this way, by adjusting the depth position of the high-resolution probe 23, the surface of the sample 4 to be observed can be preferably observed with high resolution.

FIG. 7 is a view showing an observation operation of the sample 4 having the inclined internal defect structure 41.

The dashed arrows indicate the scan before using the long focus distance probe 22. The dashed arrow indicates the present scan using the high resolution probe 23.

The internal defect structure 41 of the sample 4 is inclined.

In the scan before the long focal length probe 22 is used, the depth map 53 of the internal defect structure 41 is generated. In the front scan, the probe 22 is not changed in the depth direction toward the long focal length.

In the present scan using the high resolution probe 23, an ultrasonic image of the internal defect structure 41 is generated. In the present scanning, the high-resolution probe 23 moves while gradually decreasing while reflecting the distance of the internal defect structure 41 or the like.

Fig. 8 is an enlarged view showing the detecting operation of the sample 4 having the inclined internal defect structure 41. Fig. 8 is a detailed view showing the observation operation shown in Fig. 7;

FIG. 8 shows the positional relationship between the high-resolution probe 23 and the sample 4 and the internal defect structure 41. The upper side of the sample 4 is filled with water 31 belonging to the medium. The high resolution probe 23 is in the water 31 belonging to the medium, and the focal length is the distance D.

In the left side of the figure, the high-resolution probe 23 is set such that the internal defect structure 41 of the sample 4 becomes the focus. The front end of the high-resolution probe 23 is spaced apart from the internal defect structure 41 of the sample 4 by a distance D1. Since the ultrasonic wave transmitted from the high-resolution probe 23 is refracted on the surface of the sample 4, the distance D1 of the internal defect structure 41 of the sample 4 is different from the distance D.

In the right side of the figure, the high-resolution probe 23 is set such that the internal defect structure 41 of the sample 4 becomes the focus. The front end of the high-resolution probe 23 is spaced apart from the internal defect structure 41 of the sample 4 by a distance D2.

In order to trace the internal defect structure 41, the echo from the surface of the sample 4 and the echo from the internal defect structure 41 are captured in the scanning of the long focal length probe 22, and the sound velocity of the sample 4 is generated in consideration of the sound velocity of the sample 4. Depth map 53. When the surface of the sample 4 and the internal defect structure 41 are not in the depth of focus, the depth map 53 may be generated by performing scanning before being divided into the surface of the in-focus sample 4 and scanning before focusing on the internal defect structure 41. .

FIG. 9 is a flow chart showing the observation processing by the ultrasonic imaging apparatus 1.

When the observation processing is started, the ultrasonic imaging apparatus 1 starts the processing of step S10.

In step S10, the imaging processing display device 5 performs the long-focus distance probe 22 before scanning by the control device 7 and the signal generation measuring device 6.

In step S11, the imaging processing display device 5 determines whether or not to end the long focus distance probe 22 before scanning. Imaging processing display device 5 if not At the time of the pre-beam scanning (No), the process returns to the process of step S10, and when the pre-scanning is completed (Yes), the process of step S12 is performed.

In step S12, the imaging processing display device 5 creates a depth map 53 on the surface of the sample 4 or on the internal defect structure 41 of the sample 4.

In step S13, the imaging processing display device 5 performs position adjustment of the vertical direction (Z-axis direction) of the high-resolution probe 23 by the control device 7.

In step S14, the imaging processing display device 5 performs the present scanning of the high-resolution probe 23 by the control device 7 and the signal generation measuring device 6.

In step S15, the imaging processing display device 5 determines whether or not the present scanning of the high-resolution probe 23 is ended. When the pre-scanning is not completed (No), the imaging processing display device 5 returns to the processing of step S13, and when the pre-scanning is completed (Yes), the processing of step S16 is performed.

In step S16, the imaging processing display device 5 generates an image of high resolution, and the processing of Fig. 9 is ended.

FIG. 10 is a diagram showing the depth map 53.

As shown in FIG. 10, the ultrasonic imaging apparatus 1 represents the depth map 53 in a three-dimensional oblique view. Accordingly, the ultrasonic imaging apparatus 1 can represent the internal defect structure 41 of the sample 4 in three dimensions.

(Modification)

Furthermore, the present invention is not limited to the above embodiment, and includes various changes. Form. For example, the above-described embodiments are described in detail to explain the present invention in an easy-to-understand manner, but are not limited to those having all of the constituents described. One of the configurations of one embodiment may be replaced with another configuration, and a configuration of another embodiment may be added to the configuration of a certain embodiment. Further, addition, deletion, and replacement of other configurations may be performed for one of the configurations of the respective embodiments.

In each embodiment, it is indicated that the control line or the information line is deemed necessary in the description, but not all control lines or information lines are necessarily indicated on the article. In fact, even if you imagine that almost all of them are connected to each other.

As a modification of the present invention, for example, the following (a) to (g) are exemplified.

(a) The means for adjusting the distance between the high-resolution probe 23 and the observation position of the sample 4 is not limited to the above-described type. For example, it may be an adjustment means for moving only the high-resolution probe 23 in the depth direction, or an adjustment means for moving the water tank 3 or the sample 4 in the depth direction.

(b) The ultrasonic detecting unit 2 may be configured to have three or more probes, and may select an appropriate probe to be used in the scanning in response to the result of the pre-scanning. Accordingly, an appropriate probe can be selected in response to the observation position of the sample 4.

(c) The long focal length probe 22 and the high resolution probe 23 of the ultrasonic contact unit 2 may be scanned even if they constitute a spatial coordinate position in which the relative polarities are switched. Accordingly, there is no need to adjust the position of the depth map 53.

(d) The ultrasonic detecting unit 2 constitutes a long focal length probe even if it is mounted Any of 22 and the high-resolution probe 23, and the long-focus distance probe 22 and the high-resolution probe 23 are detached from the ultrasonic detecting unit 2 and are replaceable.

(e) The ultrasonic imaging apparatus 1 may be displayed on the display means even if the depth map 53 of the observation position and the scanning result of the high-resolution probe 23 are combined.

(f) The ultrasonic imaging apparatus 1 may make the scanning speed in the ±Y direction in the front scanning faster than the scanning speed in the ±Y direction in the scanning.

(g) The ultrasonic imaging apparatus 1 is not limited to the case where the scanning is performed after the front scanning is performed in the XY area of the sample 4. For example, the ultrasonic imaging apparatus 1 may perform the current scanning on the one-line area after performing the pre-scanning in the one-line area of the sample 4, and may repeat the pre-scan and the present in the pixel unit. Limited.

1‧‧‧Ultrasonic imaging device

2‧‧‧Supersonic detection unit (ultrasonic detection means)

21‧‧‧Encoder

22‧‧‧Long focus distance probe

221‧‧‧Piezoelectric components

23‧‧‧High resolution probe

231‧‧‧Piezoelectric components

24‧‧‧ switch

3‧‧‧Sink

31‧‧‧ water

4‧‧‧ samples (observation position)

5‧‧‧Image processing display device

51‧‧‧Scan Control Department

52‧‧‧Time Control Department

53‧‧‧Deep mapping

54‧‧‧Portrait Generation Department

6‧‧‧ Signal generation measuring device

61, 62‧‧‧ pulse wave transmitter

64‧‧‧Amplifier

65‧‧‧A/D conversion department

66‧‧‧Signal Processing Department

7‧‧‧Control device (control means)

81‧‧‧X-axis drive (scanning means)

82‧‧‧Y-axis drive (scanning means)

83‧‧‧Z-axis drive (depth adjustable means)

Claims (10)

An ultrasonic imaging apparatus characterized by: an ultrasonic detecting means capable of switching a wide range of decomposition energy and a depth of focus; a scanning means for scanning the ultrasonic detecting means in a planar direction; and a depth adjustable means Adjusting the interval between the ultrasonic detecting means and the sample; and controlling means for setting the width of the depth of focus to the first depth of focus by setting the decomposition energy of the ultrasonic detecting means to the first decomposition energy The scanning means scans to obtain a depth map of the observation position of the sample, and the decomposition of the ultrasonic detecting means can be set to a second decomposition energy higher than the first decomposition energy, and the width of the depth of focus is set to be higher than the first focus. a second depth of focus having a narrow depth, wherein the ultrasonic focusing means and the observation are performed by the depth adjusting means in a manner that the second focus depth of the ultrasonic detecting means includes the observation position related to the depth mapping The distance of the position can be adjusted, and the above-mentioned ultrasonic detecting hand is made by the above scanning means. The segment is scanned. The ultrasonic imaging apparatus according to claim 1, wherein the ultrasonic detecting means comprises a wide focus depth probe and a high resolution probe, and the wide focus depth probe is capable of detecting the first decomposition energy. The width of the depth of focus is the first depth of focus, and the resolution of the high resolution probe is the second decomposition energy, and the depth of focus of the detection is the second depth of focus. The ultrasonic imaging apparatus according to claim 2, wherein the frequency of the ultrasonic wave of the wide focus depth probe is lower than the frequency of the ultrasonic wave of the high resolution probe. The ultrasonic imaging apparatus according to claim 2, wherein the control means scans the wide focus depth probe in a planar direction by the scanning means to obtain the depth map of the observation position. The ultrasonic imaging apparatus according to claim 4, wherein the control means fixes the interval between the wide focus depth probe and the sample in scanning in a planar direction of the wide focus depth probe. The ultrasonic imaging apparatus according to claim 2, wherein the control means performs the scanning means more closely than the scanning by the scanning means and using the wide focus depth probe, and uses the high resolution probe Scan of the needle. The ultrasonic imaging apparatus according to claim 2, wherein the control means performs the scanning means by using the scanning means at a slower speed than the scanning by the scanning means and using the wide focus depth probe. Scanning of the above high resolution probe. The ultrasonic imaging apparatus according to claim 2, wherein the control means displays the depth map of the observation position and the scan result of the high-resolution probe to display the display means. The ultrasonic imaging apparatus according to claim 1, wherein the ultrasonic detecting means is mounted with the wide focus depth probe of the first focus depth contact and the high resolution of the second focus depth detection. Any one of the probes, and the wide focus depth probe and the high resolution probe described above are detachable from the ultrasonic detecting means and are replaceable. An observation method using an ultrasonic imaging apparatus using an observation method of an ultrasonic imaging apparatus having an ultrasonic wave detecting means capable of switching a wide range of decomposition energy and depth of focus; and scanning means for causing said ultrasonic wave The detecting means scans in the plane direction; the depth adjustable means adjusts the interval between the ultrasonic detecting means and the sample; and the control means; the observation method using the ultrasonic imaging apparatus is characterized in that: the above control means will The decomposition of the ultrasonic detecting means can be set to the first decomposition energy, the step of setting the width of the depth of focus to the first depth of focus, and the step of scanning the ultrasonic detecting means in the planar direction by the scanning means; a step of depth mapping of an observation position of the sample; the control means sets the ultrasonic detecting means to a second decomposition energy higher than the first decomposition energy, and sets a width of the focus depth to be narrower than the first focus depth 2 steps of depth of focus; and above the above ultrasonic detection means The second embodiment comprises the depth of focus position of the observation related to the above-described depth map, by the above-mentioned deep side The step of scanning the ultrasonic detecting means by the scanning means by adjusting the distance between the ultrasonic detecting means and the observation position by adjusting the degree.