JPH08313498A - Ultrasonic microscope - Google Patents

Abstract

PURPOSE: To provide an ultrasonic microscope capable of setting the focus matching position of an internal interface desired to be detected without performing complicated operation. CONSTITUTION: An ultrasonic microscope is equipped with an external input device 121 inputting the data of a sample 105, a Z moving part 120 relatively moving an acoustic lens 104 and the sample 105 in a Z-direction, a computer 100 controlling the Z moving part moving the focus of the acoustic lens to the surface of the sample on the basis of the data of the sample, a gate 110 taking out only a reflected wave desired to be detected from the reflection signal from the sample and a gate setting part 111 setting the gate 110 at the position and width desired to be detected on the basis of the data of the sample and constituted so that the acoustic lens or the sample is moved in the Z- direction by an indicated value at every one scanning of an X- or Y-axis and the moving quantity of the gate is calculated from the moving quantity in the Z-direction and the gate is moved from a set position desired to be detected by the moving quantity at every Z-movement.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic microscope for obtaining an ultrasonic image by using a focus type ultrasonic acoustic lens (ultrasonic probe).

[0002]

2. Description of the Related Art Conventionally, a focus type acoustic lens is used,
An ultrasonic microscope that images the inside of a sample in B mode or C mode is known. In an ultrasonic microscope using such a focus type acoustic lens, an image with high resolution can be obtained, but the focus position changes due to the influence of the sound velocity of the sample, etc., so it is necessary to focus on the position to be observed. Becomes

In the work, the received signal of the acoustic lens is observed with an oscilloscope and the like, the reflection signal to be detected is found from the signal, the distance between the sample and the acoustic lens is changed, and the position where the reflection to be detected is maximized is found. , Set the position and width of the gate. Next, the acoustic lens or the sample is two-dimensionally scanned in parallel with the surface of the sample for imaging.

However, among the above operations, the focusing work requires specialized knowledge such as knowledge about the acoustic lens, knowledge about the acoustic characteristics inside the sample, and knowledge about electronic equipment related to the operation of the oscilloscope. It is difficult for anyone other than a technician to operate an ultrasonic microscope.

In order to solve the above-mentioned problems, the applicant of the present invention has previously set the position and width of the gate in the reflected wave from the sample in Japanese Patent Laid-Open No. 5-333007, and gates the acoustic lens close to the sample. We proposed a method that adjusts the gain so that the reflection intensity inside becomes constant and detects the in-focus position according to the gain change.

Further, there is a method in which an acoustic lens is moved in the depth direction of a sample while scanning a plane and an internal image is drawn at the focus of the acoustic lens to search for an internal image to be detected.
-230849.

[0007]

However, as previously proposed, the position and width of the gate are set for the reflected wave from the sample, and the signal intensity in the gate becomes constant while the focus type acoustic lens is brought closer. The method of adjusting the gain as described above and detecting the in-focus position from the position where this gain change curve value is the minimum is effective if the reflected wave to be detected appears, but the internal interface to be detected is directly below the acoustic lens. If not, there is a problem that a reflected wave does not appear and focusing cannot be performed.

Further, in the method of moving the acoustic lens in the depth direction of the sample while scanning the plane and drawing the internal image at the focus of the acoustic lens to search for the internal image to be detected, the gate is always in focus. Since the depth is imaged differently depending on the plane scanning position because it is set, and therefore there is no internal interface to detect at the plane scanning position, the internal interface cannot be imaged and the focus position Is difficult to find. Further, even when the gate is fixed, the waveform of the focus does not always appear in the gate when the surface is scanned, and even if the reflected wave enters the gate, it does not necessarily mean that the focus is in focus. , Even if it is made into an image, it becomes a blurry image that is out of focus, and unnecessary reflected waves such as surface reflections enter the gate at the same time, and it is not possible to detect only the reflected waves at the internal interface, so the focused image Is hard to get.

The present invention has been made in order to solve the above-mentioned problems in the conventional ultrasonic microscope, and it is possible to set an in-focus position of the internal interface to be detected without performing a complicated operation. The purpose is to provide a microscope.

[0010]

In order to solve the above-mentioned problems, the invention according to claim 1 is characterized in that a focus type ultrasonic acoustic lens is planarly scanned in the X-axis and Y-axis directions, and the acoustic lens is electrically driven. An ultrasonic wave generated by inputting a specific pulse signal to the sample, and a reflected wave from the sample is received by the acoustic lens and detected to detect a plane image in an ultrasonic microscope, and the thickness of the sample and Sample data input means for inputting data such as depth to be detected and sample sound velocity, Z-axis moving means for relatively moving the acoustic lens and the sample in the Z-axis direction, and the acoustic lens to which the sample can be attached Of a known distance, and the Z-axis so as to move the focus of the acoustic lens from the Z-axis position of the sample data and the sample-fixing means input from the sample-data inputting means to the surface position of the sample. Transfer A focus movement control means for controlling the means, a time gate for extracting only a reflected wave to be detected from a reflection signal from the sample, and a time gate for detecting the sample based on the sample data input from the sample data input means First time gate control means for setting the position and width; Z-axis movement control means for moving the acoustic lens or the sample by a designated value in the Z direction for each scanning of the X-axis or the Y-axis; The gate movement amount is calculated based on the movement amount moved by the Z-axis movement control means from the position to be detected of the sample set by the first time gate setting means, and the gate movement amount time gate is calculated for each Z-axis movement. And second time gate control means for moving the.

According to a second aspect of the present invention, in the first aspect of the invention, a moving direction input means for inverting and moving the Z-axis direction for each drawing of the plane image, and for each drawing of the plane image. Position input means for inputting a desired position on the planar image, scanning range input means for inputting a desired scanning range on the planar image for each drawing of the planar image, and the acoustic lens to the input position XY axis movement control means for moving in the XY axis directions, a focus position input means for inputting a focused position at a target position on the plane image, and a focus position input means for inputting. A focus position moving means for moving the acoustic lens or the sample in the Z-axis direction at the focus position, and a gate control hand for setting a time gate position at the focus position input by the focus position input means. When the reflected signal in the gate, is intended to provide a gain control means for adjusting the gain to be drawn optimum image.

According to a third aspect of the present invention, in addition to the first or second aspect of the invention, the acoustic lens is configured to be replaceable, and when the acoustic lens is attached, individual information such as the focal length of the acoustic lens is attached. The acoustic lens identification means capable of obtaining

In the ultrasonic microscope constructed as described above, by inputting the thickness of the sample from the sample data input means, the focus movement control means moves the surface of the sample to the focus position of the acoustic lens by the Z-axis movement means. Is controlled to move. The temporal position of the surface reflected wave at this point is known. From the position of the surface reflection, the time gate is set by the first time gate control means to the thickness of the sample or the position and width of the internal reflection obtained from the depth to be detected and the sound velocity of the sample. Then, in the state where the Z-axis position and the time gate position and width are set, scanning in the XY-axis directions is started. The Z-axis position of the acoustic lens or the sample is controlled to be moved by the Z-axis movement control means for each scanning of the XY axes. Further, the temporal movement amount of the reflected wave is obtained from the change in the distance between the acoustic lens and the sample every time the Z-axis position is moved, and the time gate is moved by the second time gate control means by the temporal movement amount.

Here, the moving direction of the Z axis is input from the moving direction input means, and the target position on the image rendered on the plane is designated by the XY axis movement control means, and is used for the next plane rendering. Enter the position so that it is easy to see on the screen, for example, in the center. Further, the necessary range of the plane image is input by the scanning range input means so that the target image can be drawn with an appropriate image size when the plane is drawn next time. The Z-axis coordinate of the acoustic lens or the sample at the in-focus position input by the in-focus position input unit is input by the in-focus position input unit that inputs the in-focus position from the obtained planar image. Is moved again by the focus position moving means and the time gate position at the position input by the focus position input means is set by the gate control means. Then, the gain control means adjusts the gain so that the image drawn by the reflection signal in the gate set here becomes optimum. When the acoustic lens is replaced, the individual information of the acoustic lens, for example, the focal length is passed to the ultrasonic microscope side by the acoustic lens identification means.

[0015]

【Example】

(First Embodiment) Next, an embodiment will be described. FIG. 1 is a block diagram showing the first embodiment of the ultrasonic microscope according to the present invention. In FIG. 1, 101 is a pulse wave transmitter,
The electric transmission pulse wave generated in the pulse wave transmission unit 101 is transmitted only in one direction.
After passing through 2, it is input to the transducer 103 and converted into ultrasonic waves. Then, this ultrasonic wave is transmitted to the transducer 103.
Is transmitted through the acoustic lens 104 to which is adhered and is converged into a minute spot. Sample in the aquarium 106
105 is fixed, and between the acoustic lens 104 and the sample 105,
The coupler liquid 107 is filled so that ultrasonic waves can propagate. The reflected wave from the sample 105 is transmitted again through the acoustic lens 104, converted into an electric signal by the transducer 103, and input to the attenuator 108 through the circulator 102.

The amount of attenuation of the attenuator 108 is calculated by the computer 100.
The signal that has passed through the attenuator 108 is amplified by the amplifier 109 and input to the gate 110. The position and width of the gate 110 are determined by the computer 100, and are set by the gate setting unit 111. The signal obtained by extracting the target reflected waveform by the gate 110 is input to the peak detector 112, and the peak value of the waveform is detected. The output of the peak detector 112 is input to one terminal of the comparator 113 and also to the A / D converter 114. To the other input terminal of the comparator 113,
The threshold value supplied from the threshold value setting unit 115 is input.
The comparator 113 is turned on only when the peak detection value exceeds the threshold value, and the output of the comparator 113 is connected to the computer 100 via the bus 122.

The signal converted into a digital signal by the A / D converter 114 is input to the image memory 116. The bus 122 has an image memory 116, a display unit 117, an external input device 121, a pulse wave transmission unit 101, and a gate setting unit 111.
, Attenuator 108, X moving unit 118, Y moving unit 119, and Z moving unit 120 are connected to each other, and X, Y, Z moving units 118, 119 are connected.
, 120 can move the acoustic lens 104 by a specified distance from the computer 100. In addition,
Instead of moving the acoustic lens 104, the water tank 106 may be moved. Then, the pulse wave transmission unit 101 generates a transmission pulse wave according to the transmission timing signal from the computer 100, and the gate setting unit 111 uses the transmission timing signal from the computer 100 to calculate the transmission pulse wave.
The gate signal is set at a time delayed by the value of the gate position designated by 100, and the gate width designated by the computer 100 is transmitted to the gate 110. Further, a memory 123 is connected to the bus 122, and a simple focusing program 123a and a drawing program 123b are stored in this memory 123.

Next, the operation of the ultrasonic microscope thus constructed will be described with reference to the flow chart of the simple focusing program 123a stored in the memory 123 shown in FIGS. As a sample, a mold IC simply illustrated as shown in FIG. 2 will be described. First, the computer 100 reads the simple focusing program 123a from the memory 123 and executes it from the start step 501 of the flowchart shown in FIG. Generally, an ultrasonic microscope is often used when inspecting for peeling or cracks between a mold inside a molded IC and a chip or a lead frame. In the mold IC, the thickness and the depth to the chip or the lead frame are usually known by design, so that the operator inputs the sample information from the external input device 121 in the sample data input step 502. The information input here includes the sample thickness t, the depth d from the sample surface to the position to be inspected, the sound velocity v of the sample, and the thickness of the sample folder for fixing the sample, if any.

Next, the gate position and width setting step 50
In 3, the position of the time gate based on the focal point of the acoustic lens 104 (the delay time from the transmission pulse signal until the reflected signal passes through the underwater focal point of the acoustic lens 104), which is known in the design of the electric circuit, and the acoustic lens 104 The gate width determined in advance according to the characteristics of (1) is set in the gate setting unit 111 from the computer 100.

Next, in step 504 of moving the focal point of the acoustic lens to the sample surface, the focal point of the acoustic lens 104 is focused on the water tank 10 based on the thickness of the sample input from the external input device 121.
It moves to the surface of the sample 105 placed on the surface 6 by the Z moving unit 120. The Z movement amount by the Z movement unit 120 can be obtained by calculation because the distance between the focal position of the acoustic lens 104 and the bottom of the water tank 106 on which the sample 105 is placed is known. In addition, items that affect the height position of the sample such as the sample folder are adjusted in this calculation process.

Next, in the internal reflection gate setting step 505, the ultrasonic wave propagates from the surface d to the position to be inspected, which is input from the external input device 121 to the position to be inspected from the depth d to the position to be inspected. The gate is set for internal reflection by calculating the time and inputting it to the gate setting unit 111 in addition to the gate position of the surface reflected wave.

Next, the flow chart shown in FIG. 6 following the flow chart shown in FIG. 5 will be described with reference to the scanning diagram shown in FIG. First, in step 601, the process of starting scanning in the X direction and converting one line into an image is executed, and the X moving unit 118 moves the acoustic lens 301 from the point A 303 in the + X direction, and the line of one line is stored in the image memory 116. Enter the image.

Next, in the Y movement end confirmation processing step 602, the end of the Y direction movement is confirmed, and if the movement in the Y direction is not completed and the movement in the Y direction is possible, the Y movement is confirmed in step 603.
The moving process in the direction is executed, and the Y moving unit 119 moves the acoustic lens 301 in the + Y direction. Up to this point, it is the same as the normal plane scanning.

Next, in step 604, the Z direction moving process is executed, the Z moving unit 120 moves the acoustic lens 301 in the + Z direction, and the focus of the acoustic lens 301 is point B 304.
Go to The amount of movement in the Z direction may be input by the operator from the external input device 121, or may be calculated from the thickness of the sample and the number of movements in the Y direction.

Next, in step 605 of moving the gate position by the amount of movement in the Z direction, the gate position is moved by the amount of change in the ultrasonic propagation time in water by the amount of change in the distance from the sample 302 by moving the acoustic lens 301 in the Z direction. Moving. FIG. 4 is a diagram showing the movement of the reflection waveform and the movement of the gate position when the focus of the acoustic lens 301 moves from the point A 303 to the point B 304. A
Reflection wave 401 at point 303 causes reflection 403 inside the sample.
The gate position 404 at the point A is set by the gate signal 405 so that the signal can be detected. Note that reference numeral 402 denotes the reflection of the reflected wave 401 at the point A 303 on the sample surface. When the acoustic lens 301 is moved in the Z direction and the focus is moved to the point B 304, the reflection 407 inside the sample advances temporally as shown by the reflected wave 406 at the point B 304. This is due to the change in propagation time due to the shorter distance in water. This time can be calculated and obtained from the known speed of sound of water (coupler liquid) and the amount of movement in the Z direction. B point 304
Since the gate position 408 in FIG. 6 detects the reflection 407 inside the sample, it is set to the position 409 advanced by the time (t) when the internal reflection advances.

By repeating the above operation until the movement in the Y direction is completed, the focus is gradually moved along with the movement in the Y direction while always detecting the reflection waveform of the same depth of the sample. A plane image as shown can be drawn. FIG. 8 shows an ultrasonic image 801 of the mold IC, and an internal image 802 when the acoustic lens is focused on the surface appears in the upper part of the screen by the above drawing. When the drawing is further continued, the internal image 803 appears when the focus is above the interface between the chip and the mold. When the drawing is further continued, an internal image 804 is displayed when the interface between the chip and the mold is in focus. The focused Y-direction range varies depending on the amount of movement in the Z-direction per scan and the depth of the acoustic lens. As the drawing continues, the focus moves to a deeper position and the internal image when the back surface of the sample is in focus 80
5 appears.

FIG. 7 is a diagram showing a flow chart of the processing after the plane image shown in FIG. 8 is obtained, that is, the processing after the movement in the Y direction of the flow chart shown in FIG. 6 is completed. Steps for deciding whether to move the drawing range
In 701, when the drawing range moving process is executed, a cursor is displayed on the plane image in the drawing position input step 702, and the operator moves the cursor to specify the portion to be drawn at the center of the screen in the next drawing. be able to. For example, when it is desired to draw the mold IC chip in the center, this operation is effective. Further, by setting the drawing range, the scanning width can be set according to the size of the sample that can be seen from the planar image. When the drawing position and range are designated, in step 703, the process of moving the acoustic lens 301 in the XY direction within the drawing range is executed.

Next, in the Z movement direction reversal determination step 704, in the case of reversing the Z movement direction, in step 705, the Z movement direction is set to the opposite direction from the drawing of the next planar image, and the sample is drawn in the previous drawing. It is possible to set the process in which the Z lens is moved in the direction in which the acoustic lens and the acoustic lens come closer to each other so that the sample and the acoustic lens move in the direction to move away from each other. As a result, when the focus of the acoustic lens goes beyond the depth to be inspected, it is possible to draw while returning it. At this time, the time gate position also moves in the opposite direction.

Next, in step 706 of whether or not to perform the focusing positioning movement, if the focusing positioning movement is performed, the image of the depth to be inspected is the most out of the plane images drawn as described above. The clearly visible portion (the focused portion) is designated by the cursor displayed on the screen, and the position in the Z direction and the gate position of the acoustic lens at that position are reset and focused. That is, first, in the focus position designation step 707, the cursor displayed on the plane image is moved. Since the image is an image in which the in-focus position changes as it advances in the Y direction, the image gradually becomes in focus. Here, the operator determines the place where the image of the depth of the sample to be inspected is the clearest with the cursor. When the focus position is determined, in step 708, the computer 100 resets the Z position and time gate position of the acoustic lens at the focus position to the values at the position determined by the cursor. Then, in the attenuator value setting step 709,
The attenuator 10 is set so that the output of the peak detection unit 112 does not exceed the threshold value set in advance by the threshold value setting unit 115.
Set 8.

Thus, the processing of the simple focusing method ends (step 710). After that, when drawing is performed by normal plane scanning, it is possible to draw an in-focus ultrasonic image of the depth to be inspected of the sample.

On the other hand, in step 706 of whether or not to perform the focusing positioning movement, if the focusing positioning movement processing is not executed, the value returns to the flowchart of FIG. The process of drawing a plane while moving the position in the Z direction can be repeated.
This makes it possible to obtain an image in which the focus of the acoustic lens is further moved.

(Second Embodiment) When the inside of the sample is scanned in the XY plane with an ultrasonic microscope, as shown in FIG.
If the surface of the sample is not parallel to the XY plane, the distance between the sample 901 and the acoustic lens 902 changes between the acoustic lens 902 at a certain scanning position A and the acoustic lens 902 at a different scanning position B, and the reflection waveform moves in the time direction. If the position of the time gate is fixed, it will be out of the reflected wave of the internal interface to be detected, and it will not be possible to image it. In such a case, the tilt adjustment means (gonio stage) of the sample table is used for correction. However, when there is no inclination adjusting means or when the inclination cannot be completely corrected, an electrical inclination correction called a tracking gate is performed.

Next, the inclination correction method using the tracking gate will be described with reference to FIG. The reflected wave 1001 has waveforms of a sample surface reflection 1002 and an internal reflection 1003. When the sample is tilted, the reflected wave moves in the direction of arrow 1004 every time the acoustic lens is scanned. When this movement amount is large, in the fixed gate signal 1006 that sets the normal fixed gate position 1005, the reflected wave deviates from the gate and a portion cannot be drawn. Therefore, the first gate position 1007 is set with a width that covers the entire movement range of the surface reflection 1002 by the first gate signal 1008. The peak position of the reflection waveform detected in the thus set first gate is detected and used as a reference for setting the second gate signal 1010 for setting the second gate position 1009. Next, using a delay line for electrically delaying the detected reflected wave 1001 by a desired time, a reflected wave 1012 obtained by delaying the reflected wave 1001 by a desired time from this base point position is obtained. That is, the surface reflection 1002 corresponds to the surface reflection 1014, and the internal reflection 1003 corresponds to the internal reflection 1013. Therefore, by the constant time t _{D obtained} by adding the time from the peak position of the surface reflection 1014 to the internal reflection 1013 to the time delayed using the delay line,
The second gate signal 1010 is set.

From the above, even if the surface reflection 1002 moves, the peak position of the surface reflection 1002 is detected, and the second gate is set at a position shifted from this peak position by a fixed time t _D. Therefore, the internal reflection 1013 of the reflected wave 1012 delayed by the delay line can be reliably detected. Then, the reflected waveform detected in the second gate signal 1010 is imaged. The reason why the gate is set on the reflected wave 1012 after passing through the delay line is to consider the time lag of the electric circuit until the base point is detected.

By introducing this follow-up gate into the first embodiment, a plane image can be obtained even when the sample is set to be inclined, but when the time gate position is moved, the first gate signal is obtained. Only 1008 is moved and set as in the first embodiment. Now the surface reflection is the first gate signal 1008
The second gate signal 1011 can always be set and set according to the internal reflection 1013.

Third Embodiment In the first embodiment, the acoustic lens is focused on the sample surface and the gate is set for internal reflection. However, when the depth of the internal interface to be inspected of the sample is unknown, the time gate is used. Setting becomes difficult. In this case,
The B-mode image of the sample shown in is drawn, and the operator inputs the position of the internal interface from this image.

That is, first, similarly to the first embodiment, the acoustic lens is focused on the surface of the sample. Then, the gate is temporally set from the position of surface reflection. From this state, the Z direction is moved for each X scan, the acoustic lens and the sample are brought close to each other, and a B mode ultrasonic image 1101 of the mold IC as shown in FIG. 11 is drawn. B-mode ultrasonic image of mold IC
At 1101, an image 1102 of surface reflection first appears, and then an image 1103 of internal reflection appears.

When the drawing of the B-mode image thus obtained is completed, the line cursor 1104 for inputting the time gate position is displayed, and the operator moves the line cursor 1104 to designate the internal interface to be detected. Then, by inputting, the acoustic lens is moved in the Z direction, and the waveform of the internal interface to be inspected of the sample is reset so that it enters the gate.

At this point, since the acoustic lens is simply moved so that the internal reflection is aligned with the gate position where the B mode is drawn, the acoustic lens is not in focus at the position of the internal interface to be inspected of the sample. Then, the plane image of the first embodiment is drawn. This allows focusing of the internal interface of the sample to be inspected.

(Fourth Embodiment) The acoustic lens of the ultrasonic microscope can be selected from several types according to the sample, but the frequency and focal length of the ultrasonic wave may differ from each other. In particular, when the focal lengths are different, when the acoustic lens is replaced in the process of focusing on the sample surface performed in the first example, the focal point cannot be moved to a normal position, and the worst case may cause the sample to collide with the acoustic lens. is there.

In order to avoid such a problem, at the same time as replacing the acoustic lens, the status box that is a set with the acoustic lens is also replaced, and the acoustic lens is recognized on the ultrasonic microscope side, and individual information on the acoustic lens is obtained. To be able to set.

[0042]

As described above on the basis of the embodiments,
According to the present invention, the operator can input the information such as the thickness of the sample to first focus the acoustic lens on the surface of the sample, and set the time gate according to the reflected wave inside the sample to be inspected. can do. Furthermore, the acoustic lens is moved in the Z direction for each scanning, and the time gate is also moved so as to match the internal reflection to be inspected, so that the internal reflected wave of the same depth is always detected and the focus of the acoustic lens is slightly reduced. It is possible to obtain a planar image that has moved in steps. By selecting the in-focus portion from the plane image obtained in this way, it is possible to focus on the inside of the sample to be inspected and set a time gate for the internal reflection. The operator can easily focus the ultrasound microscope from the image.

When the sample is tilted, a plane image can be similarly obtained by setting the first gate for setting the follow-up range of the follow-up gate in accordance with the movement in the Z direction. Further, the gate position can be correctly set for the internal reflection by the operator designating the position of the internal reflection from the B-mode image of the sample. Further, even if the acoustic lens is replaced, the operator can operate the acoustic lens without changing the focal length of the acoustic lens by changing the status box having the information of the acoustic lens.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of an ultrasonic microscope according to the present invention.

FIG. 2 is a diagram showing a schematic configuration of a sample used in the example shown in FIG.

FIG. 3 is a diagram showing a scanning mode of an acoustic lens in the example shown in FIG.

FIG. 4 is a diagram showing a reflection waveform and a movement mode of a gate position when the focus of the acoustic lens moves in FIG.

FIG. 5 is a flowchart for explaining the operation of the embodiment shown in FIG.

FIG. 6 is a diagram for explaining the operation of the embodiment shown in FIG.
6 is a flowchart that follows the flowchart shown in FIG. 5.

FIG. 7 is a diagram for explaining the operation of the embodiment shown in FIG.
7 is a flowchart following the flowchart shown in FIG. 6.

FIG. 8 is a diagram showing an ultrasonic image of a mold IC.

FIG. 9 is a diagram showing a scanning mode of the acoustic lens when the sample surface is not parallel to the XY scanning plane.

FIG. 10 is a diagram showing a reflected wave and a gate position for explaining a correction mode when the inclination correction is performed by the tracking gate.

FIG. 11 is a diagram showing a B-mode ultrasonic image of a mold IC.

[Explanation of symbols]

 100 Computer 101 Pulse wave transmitter 102 Circulator 103 Transducer 104 Acoustic lens 105 Sample 106 Water tank 107 Coupler liquid 108 Attenuator 109 Amplifier 110 Gate 111 Gate setting unit 112 Peak detector 113 Comparator 114 A / D converter 115 Threshold setting unit 116 Image Memory 117 Display section 118 X moving section 119 Y moving section 120 Z moving section 121 External input device 122 Bus 123 Memory

Claims (3)

[Claims] 1. A focus type ultrasonic acoustic lens is planarly scanned in the X-axis and Y-axis directions, and an ultrasonic wave generated by inputting an electrical pulse signal to the acoustic lens is incident on a sample and reflected from the sample. In an ultrasonic microscope that receives and detects a wave by the acoustic lens and draws a planar image, sample data input means for inputting data such as the thickness of the sample and the depth and sample sound velocity to be detected, and the acoustic lens. The sample is relatively Z
Z-axis moving means for moving in the axial direction, sample fixing means capable of mounting the sample and having a known distance from the acoustic lens,
Focus movement control means for controlling the Z axis moving means so as to move the focus of the acoustic lens from the Z axis position of the sample fixing means and the sample data input from the sample data input means to the surface position of the sample. A time gate for extracting only a reflected wave to be detected from a reflection signal from the sample, and a first time gate for setting the position and width of the sample to be detected based on the sample data input from the sample data input means. The time gate control means and the acoustic lens or the sample are Z-scanned for each scan of the X-axis or the Y-axis.
Z-axis movement control means for moving a specified value in the direction,
The gate movement amount is obtained based on the movement amount moved by the Z-axis movement control unit from the position to be detected of the sample set by the first time gate control unit, and the gate movement amount time is calculated for each Z-axis movement. The second to move the gate
And a time gate control means of the above. 2. The ultrasonic microscope according to claim 1, wherein a moving direction input means for inverting and moving the Z-axis direction for each drawing of the planar image, and a purpose on the planar image for each drawing of the planar image. Position input means for inputting a position to be input, scanning range input means for inputting a target scanning range on the planar image for each drawing of the planar image, and the acoustic lens to the input position in the XY axis directions. XY axis movement control means for moving, a focus position input means for inputting a focused position at a target position on the planar image, and the focus position input by the focus position input means A focus position moving means for moving the acoustic lens or the sample in the Z-axis direction, a gate control means for setting a time gate position at the focus position input by the focus position input means, and a counter in the gate. An ultrasonic microscope, comprising: a gain control means for adjusting a gain of an injection signal so that an optimum image can be drawn. 3. The acoustic lens is configured to be replaceable, and an acoustic lens identifying means is provided which can obtain individual information such as a focal length of the acoustic lens when the acoustic lens is attached. Claim 1 or 2
The described ultrasonic microscope.