An ultrasonic scanning imaging method and system for accurately locating the internal interface of a chip

Abstract

The present invention provides an ultrasonic scanning imaging method and system for precisely locating the internal interface of a chip, belonging to the field of microelectronics reliability testing and failure technology. The method includes: obtaining the thickness of the electronic component of the integrated circuit to be tested; scanning the device from the side using X-rays to obtain the thickness of the packaging material; selecting a transducer based on the thickness of the device; obtaining the propagation velocity of the ultrasonic wave in the packaging material and the test medium; calculating the height of the probe from the top surface of the device based on the ultrasonic scanning imaging principle; calculating the distance between the probe and the bottom of the test medium; calculating the transit time of the ultrasonic wave in the packaging material based on the propagation velocity of the ultrasonic wave in the packaging material and the thickness of the packaging material; and calculating the transit time of the ultrasonic wave in the test medium based on the propagation velocity of the ultrasonic wave in the test medium and the height of the probe from the top surface of the device. The present invention improves the efficiency of ultrasonic scanning testing in DPA testing of integrated circuit electronic components.

Description

Technical Field

[0001] The present invention belongs to the field of microelectronic reliability testing and failure technology, and more specifically, relates to an ultrasonic scanning imaging method and system for accurately locating the internal interface of a chip. Background Art

[0002] Ultrasonic scanning microscopy (USM) imaging is a key method for destructive physical analysis (DPA) of plastic-encapsulated integrated circuit (IC) electronic components. It exploits the differences in acoustic impedance, absorption, and reflection of ultrasonic waves due to the density of the material's internal structure. A specific acoustic component transmits and receives short, high-repetition-rate ultrasonic pulses. After the sound waves interact with the sample being tested, the reflected waves are received and converted into video signals. To form an acoustic image, the scanning mechanism moves back and forth over the sample. The intensity and phase of the reflected waves at each point on the sample are recorded sequentially and synchronously, converted into pixels with a specific grayscale value, and displayed on a high-resolution display.

[0003] Ultrasonic scanning can perform non-destructive testing of defects such as inclusions, cracks, air stratification and voids inside semiconductor devices, enabling qualitative and quantitative analysis of internal material defects. It is an important part of the destructive physical analysis (DPA) test of electronic components.

[0004] Conventional ultrasonic scanning of semiconductor devices requires adjusting the vertical position of the acoustic probe to obtain the device's reflected wave, and then achieving clear ultrasonic imaging of the specific layer interface through reflected wave band selection and focusing. Due to the differences in external package size, thickness and material of different components, the location of the reflected wave also varies greatly. In addition, the internal structure of the components is different, and the distance between the chip layer, adhesive layer, substrate and pin layer and the package surface will vary. When performing ultrasonic scanning on these specific interfaces, a large amount of repeated band selection and focus adjustment is required to obtain clear imaging of the corresponding layer. Depending on the different components and the operator's experience and ability, the entire debugging process takes from several hours to a day, which is very time-consuming, especially when ultrasonic scanning tests need to be performed on different types of components. Summary of the Invention

[0005] In view of the defects of the prior art, the purpose of the present invention is to provide an ultrasonic scanning imaging method and system for accurately locating the internal interface of a chip, aiming to solve the problem of low efficiency of ultrasonic scanning of existing semiconductor devices.

[0006] To achieve the above objectives, the present invention provides, on the one hand, an ultrasonic scanning imaging method for accurately locating the internal interface of a chip, comprising the following steps:

[0007] Perform visual inspection on the electronic components of the integrated circuit to be tested and obtain the thickness of the electronic components of the integrated circuit to be tested;

[0008] X-rays are used to perform a side scan of the integrated circuit electronic component to be tested, to locate the chip or substrate layer, and to obtain the thickness of the packaging material; wherein the chip or substrate layer is encapsulated with the packaging material between the chip or substrate layer and the upper surface of the integrated circuit electronic component to be tested;

[0009] Select the transducer according to the thickness of the integrated circuit electronic components to be tested;

[0010] Obtaining the propagation velocity of the ultrasonic wave in the packaging material and the test medium according to the packaging material and the ultrasonic scanning test medium; wherein the electronic component of the integrated circuit to be tested is placed in the test medium during the ultrasonic scanning imaging;

[0011] Using the thickness of the packaging material, the focal length of the transducer, and the propagation speed of ultrasound in the packaging material and the test medium, and based on the principle of ultrasonic scanning imaging, calculate the height of the transducer probe from the top surface of the integrated circuit electronic component to be tested when the ultrasound is imaging at the chip layer or substrate layer;

[0012] Calculate the distance between the probe and the bottom of the test medium based on the height of the probe from the upper surface of the electronic component of the integrated circuit to be tested and the thickness of the electronic component of the integrated circuit to be tested;

[0013] Calculate the transit time of ultrasonic waves in the packaging material based on the propagation speed of ultrasonic waves in the packaging material and the thickness of the packaging material;

[0014] The transit time of the ultrasonic wave in the test medium is calculated based on the propagation speed of the ultrasonic wave in the test medium and the height of the probe from the upper surface of the electronic component of the integrated circuit to be tested.

[0015] Further preferably, the height WP of the probe from the upper surface of the electronic component of the integrated circuit to be tested is:

[0016] WP=FD(C tm / C w )

[0017] Where F is the focal length of the transducer; D is the thickness of the packaging material; the test medium is pure water; C tm and C w are the propagation speeds of ultrasonic waves in packaging materials and pure water, respectively.

[0018] Further preferably, the distance between the probe and the bottom of the tank is:

[0019] L=WP+T

[0020] Wherein, WP is the height between the probe and the upper surface of the electronic component of the integrated circuit to be tested; T is the thickness of the electronic component of the integrated circuit to be tested.

[0021] Further preferably, the transit time TOF1 of the ultrasonic wave in the packaging material is:

[0022] C tm *TOF1=D*2

[0023] Among them, C tm is the speed of ultrasonic waves in the packaging material; D is the thickness of the packaging material;

[0024] The transit time TOF2 of ultrasound in pure water is:

[0025] C w *TOF2=WP*2

[0026] Among them, C w is the propagation speed of ultrasound in water; WP is the height between the probe and the upper surface of the integrated circuit electronic component to be tested.

[0027] In another aspect, the present invention provides an ultrasonic scanning imaging system for accurately locating the internal interface of a chip, comprising:

[0028] A microscope is used to visually inspect the electronic components of the integrated circuit to be tested and obtain the thickness of the electronic components of the integrated circuit to be tested;

[0029] An X-ray detector is used to use X-rays to perform a side scan of the integrated circuit electronic component to be tested, locate the chip or substrate layer, and obtain the thickness of the packaging material; wherein the chip or substrate layer is encapsulated with a packaging material between the chip or substrate layer and the upper surface of the integrated circuit electronic component to be tested;

[0030] A transducer is selected according to the thickness of the electronic component of the integrated circuit to be tested and is used for ultrasonic scanning imaging of the electronic component of the integrated circuit to be tested;

[0031] a material acoustic impedance table storage module, configured to store the material acoustic impedance table and obtain the propagation velocity of the ultrasonic wave in the packaging material and the test medium according to the packaging material and the ultrasonic scanning test medium; wherein the electronic component of the integrated circuit to be tested is placed in the test medium during ultrasonic scanning imaging;

[0032] The test medium tank is used to store the test medium and provide an ultrasonic test medium environment; it has built-in integrated circuit electronic components to be tested;

[0033] The data processing module is used to calculate the height of the transducer probe from the upper surface of the electronic component of the integrated circuit to be tested when the ultrasonic wave is imaged on the chip layer or the substrate layer based on the thickness of the packaging material, the focal length of the transducer, and the propagation speed of the ultrasonic wave in the packaging material and the test medium, according to the principle of ultrasonic scanning imaging; and calculate the distance between the probe and the bottom of the test medium based on the height of the probe from the upper surface of the electronic component of the integrated circuit to be tested and the thickness of the electronic component of the integrated circuit to be tested; and calculate the transit time of the ultrasonic wave in the packaging material based on the propagation speed of the ultrasonic wave in the packaging material and the thickness of the packaging material; and calculate the transit time of the ultrasonic wave in the test medium based on the propagation speed of the ultrasonic wave in the test medium and the height of the probe from the upper surface of the electronic component of the integrated circuit to be tested.

[0034] Further preferably, the height WP of the probe from the upper surface of the electronic component of the integrated circuit to be tested is:

[0035] WP=FD(C tm / C w )

[0036] Where F is the focal length of the transducer; D is the thickness of the packaging material; the test medium is pure water; C tm and C w are the propagation speeds of ultrasonic waves in packaging materials and pure water, respectively.

[0037] Further preferably, the distance between the probe and the bottom of the tank is:

[0038] L=WP+T

[0039] Wherein, WP is the height between the probe and the upper surface of the electronic component of the integrated circuit to be tested; T is the thickness of the electronic component of the integrated circuit to be tested.

[0040] Further preferably, the transit time TOF1 of the ultrasonic wave in the packaging material is:

[0041] C tm *TOF1=D*2

[0042] Among them, C tm is the speed of ultrasonic waves in the packaging material; D is the thickness of the packaging material;

[0043] The transit time TOF2 of ultrasound in pure water is:

[0044] C w *TOF2=WP*2

[0045] Among them, C w is the propagation speed of ultrasound in water; WP is the height between the probe and the upper surface of the integrated circuit electronic component to be tested.

[0046] In general, the above technical solutions conceived by the present invention have the following advantages compared with the prior art:

[0047] Beneficial effects:

[0048] The present invention provides an ultrasonic scanning imaging method and system for accurately locating the internal interface of a chip. By collecting parameter indicators such as the external dimensions in the destructive physical analysis (DFA) test of electronic components and the thickness dimensions and spacing in X-ray transmission measurement, combined with the focal length of the acoustic probe (i.e., transducer), the vertical position of the acoustic probe when the target layer is clearly imaged is calculated. Then, based on the principle of ultrasonic scanning, the approximate positions of the surface waves and the reflected waves from the chip layer are calculated, and the calculated parameters are used to select the reflected wave band, thereby enabling the ultrasonic scanning microscope to quickly locate the scanning imaging of a specific layer inside the chip, saving the time required for ultrasonic scanning in the DPA test of the integrated circuit electronic components to be tested, and improving the efficiency of ultrasonic scanning tests in the DPA test of integrated circuit electronic components. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 Schematic diagram of the working principle of ultrasonic scanning of electronic components provided by an embodiment of the present invention;

[0050] Figure 2 is a schematic diagram of generating an ultrasonic scanning waveform provided by an embodiment of the present invention;

[0051] Figure 3 Schematic diagram of the ultrasonic scanning waveform generation principle provided by an embodiment of the present invention;

[0052] Figure 4 is a distance parameter related to the X-ray measurement sample provided by an embodiment of the present invention;

[0053] Figure 5 This is an ultrasonic scanning image and reflection waveform diagram provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0054] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0055] On the one hand, the present invention provides an ultrasonic scanning imaging method for accurately locating the internal interface of a chip, wherein the working diagram of ultrasonic scanning imaging is as follows: Figure 1 As shown, the following steps are included:

[0056] S1: Perform DPA routine test items on the external visual inspection of the integrated circuit electronic components to be tested, and measure and record the thickness of the integrated circuit electronic components to be tested. The thickness is T. This data can also be obtained by referring to other characterization methods or device data;

[0057] S2: In the DPA routine test, X-rays are used to perform a lateral scan of the IC component under test, and then the chip or substrate layer is located. The distance D (the thickness of the packaging material) from the layer to the top surface of the chip is measured and recorded. The chip or substrate layer and the top surface of the IC component under test are encapsulated with packaging material. The IC component under test is placed at the bottom of a water tank during ultrasonic scanning and imaging.

[0058] S3: Determine the appropriate frequency transducer based on the thickness of the integrated circuit electronic component to be tested and find the transducer's focal length F. The relationship between probe frequency and focal length is known and can be provided by the equipment manufacturer, as shown in Table 1.

[0059] Table 1

[0060] Frequency (MHz) Focal length (mm) 25 20.0 30 12.7 80 9.0 100 8.0

[0061] S4: According to the packaging material of the integrated circuit electronic components to be tested and the ultrasonic scanning test medium (usually pure water), through the material acoustic impedance table, refer to Table 2, and find out the propagation speed C of the ultrasonic wave in the tested packaging material and water. tm 、C w ;

[0062] S5: Using the distance from the layer of the integrated circuit electronic component to be tested to the upper surface of the chip, the focal length of the transducer, and the propagation speed of ultrasound in the tested packaging material and water, according to the principle of ultrasonic scanning imaging, based on formula (1), the height WP of the probe from the upper surface of the integrated circuit electronic component to be tested when ultrasound is used to image the chip layer or other interface can be calculated;

[0063] WP=FD(C tm / C w ) (1)

[0064] Combined with the sample thickness, the distance L between the equipment probe and the bottom of the water tank is obtained using formula (2);

[0065] L=WP+T (2)

[0066] S6: According to the speed of ultrasonic wave in packaging material C tm and the thickness D of the packaging material, and according to formula (3), calculate the transit time TOF1 of the ultrasonic wave in the packaging material, that is, the position TOF1 where the reflected wave band appears:

[0067] C tm*TOF1=D*2 (3)

[0068] According to the propagation speed of ultrasound in water and the height WP of the probe from the upper surface of the electronic component of the integrated circuit to be tested, the transit time TOF2 of ultrasound in water, that is, the position TOF2 where the reflected wave band appears, is calculated according to formula (4);

[0069] C w *TOF2=WP*2 (4)

[0070] The overall formula for the location where the reflected wave band appears is:

[0071] C*TOF=Th*2 (5)

[0072] Where C is substituted into C w and C tm Substituting Th into WP and D, we can calculate the transit time TOF1 and TOF2 of ultrasonic wave in the material, that is, the position where the surface wave and interface wave reflection band appear; Figure 2 and Figure 3 As shown in the reflected waveform of the acoustic scan, the scanning signal represents the real-time ultrasonic signal intensity on the vertical axis, with the energy unit being V, and the horizontal axis represents the transit time information of the sample, with the unit being ns;

[0073] Calculate the corresponding test conditions, namely the distance L between the equipment probe and the bottom of the water tank, and the positions TOF1 and TOF2 where the surface wave and interface wave reflection bands appear. Then, you can set the above parameters to perform ultrasonic scanning of the integrated circuit electronic components to be tested, saving most of the debugging time; that is, place the integrated circuit electronic components to be tested in the water tank, use the corresponding transducer, and vertically adjust the transducer height so that it is at a distance L from the bottom of the water tank; select the reflection wave band in the waveform diagram, define the surface wave at TOF1, and define the measured interface layer (such as chip layer, substrate layer, etc.) band at TOF2, scan and image the integrated circuit electronic components to be tested, and decide whether to make the final fine-tuning based on the image effect to obtain a complete and clear interface acoustic scanning image, so as to judge whether it has defects such as delamination and voids.

[0074] In another aspect, the present invention provides an ultrasonic scanning imaging system for accurately locating the internal interface of a chip, comprising:

[0075] A microscope is used to visually inspect the electronic components of the integrated circuit to be tested and obtain the thickness of the electronic components of the integrated circuit to be tested;

[0076] An X-ray detector is used to use X-rays to perform a side scan of the integrated circuit electronic component to be tested, locate the chip or substrate layer, and obtain the thickness of the packaging material; wherein the chip or substrate layer is encapsulated with a packaging material between the chip or substrate layer and the upper surface of the integrated circuit electronic component to be tested;

[0077] A transducer is selected according to the thickness of the electronic component of the integrated circuit to be tested and is used for ultrasonic scanning imaging of the electronic component of the integrated circuit to be tested;

[0078] a material acoustic impedance table storage module, configured to store the material acoustic impedance table and obtain the propagation velocity of the ultrasonic wave in the packaging material and the test medium according to the packaging material and the ultrasonic scanning test medium; wherein the electronic component of the integrated circuit to be tested is placed in the test medium during ultrasonic scanning imaging;

[0079] The test medium tank is used to store the test medium and provide an ultrasonic test medium environment; it has built-in integrated circuit electronic components to be tested;

[0080] The data processing module is used to calculate the height of the transducer probe from the upper surface of the electronic component of the integrated circuit to be tested when the ultrasonic wave is imaged on the chip layer or the substrate layer based on the thickness of the packaging material, the focal length of the transducer, and the propagation speed of the ultrasonic wave in the packaging material and the test medium, according to the principle of ultrasonic scanning imaging; and calculate the distance between the probe and the bottom of the test medium based on the height of the probe from the upper surface of the electronic component of the integrated circuit to be tested and the thickness of the electronic component of the integrated circuit to be tested; and calculate the transit time of the ultrasonic wave in the packaging material based on the propagation speed of the ultrasonic wave in the packaging material and the thickness of the packaging material; and calculate the transit time of the ultrasonic wave in the test medium based on the propagation speed of the ultrasonic wave in the test medium and the height of the probe from the upper surface of the electronic component of the integrated circuit to be tested.

[0081] Further preferably, the height WP of the probe from the upper surface of the electronic component of the integrated circuit to be tested is:

[0082] WP=FD(C tm / C w )

[0083] Where F is the focal length of the transducer; D is the thickness of the packaging material; the test medium is pure water; C tm and C w are the propagation speeds of ultrasonic waves in packaging materials and pure water, respectively.

[0084] Further preferably, the distance between the probe and the bottom of the tank is:

[0085] L=WP+T;

[0086] Wherein, WP is the height between the probe and the upper surface of the electronic component of the integrated circuit to be tested; T is the thickness of the electronic component of the integrated circuit to be tested.

[0087] Further preferably, the transit time TOF1 of the ultrasonic wave in the packaging material is:

[0088] Ctm *TOF1=D*2

[0089] Among them, C tm is the speed of ultrasonic waves in the packaging material; D is the thickness of the packaging material;

[0090] The transit time TOF2 of ultrasound in pure water is:

[0091] C w *TOF2=WP*2

[0092] Among them, C w is the propagation speed of ultrasound in water; WP is the height between the probe and the upper surface of the integrated circuit electronic component to be tested.

[0093] Example

[0094] Ultrasonic scanning is performed using a BGA packaged digital circuit chip as an example;

[0095] like Figure 4 As shown, the chip thickness is measured to be T = 1.279 mm through the appearance dimensions; and the distance from the chip layer to the surface of the electronic component of the integrated circuit to be tested is obtained as D = 0.371 mm through the side scan during X-ray inspection.

[0096] Select a brand of ultrasonic scanning equipment with an 80MHz transducer according to the integrated circuit electronic components to be tested. Refer to Table 1 for transducer frequency and focal length specifications to find the transducer's focal length F = 9.0 mm.

[0097] The packaging material of the integrated circuit electronic components to be tested is epoxy resin, and its ultrasonic propagation speed C tm =2830m / s, the propagation speed of ultrasound in pure water C w =1500m / s;

[0098] Substituting into formula (1), we can get the height WP of the probe from the upper surface of the electronic component of the integrated circuit to be tested when the ultrasonic wave is imaging at the chip layer = 8.30 mm. Formula (2) can be used to get the distance L between the equipment probe and the bottom of the water tank = 9.579 mm.

[0099] The speed of the sound wave in the packaging material C tm , the propagation speed of ultrasound in pure water C w Substituting C in formula (3), the height WP of the probe from the upper surface of the electronic component of the integrated circuit to be tested, and the distance D from the chip layer to the upper surface of the chip into Th in formula (3), we can calculate the transit time of the sound wave in water TOF1 = 11067ns, and the transit time in the plastic packaging material on the sample chip TOF2 = 262.19ns;

[0100] Place the integrated circuit electronic components to be tested in the acoustic scanning water tank, adjust the vertical position of the probe so that the distance between the equipment probe and the bottom of the water tank is L = 9.579mm, and select the chip layer band to be about 262ns (i.e. TOF2) after the surface wave appearance time (i.e. TOF1), scan the chip area to obtain an image, and then fine-tune the focus and chip layer band to obtain a clear and complete chip layer image. Figure 5 As shown, we can see that the actual TOF1 value is 10993ns, and TOF2 (i.e. Figure 5 The GatePosition in the figure is 251ns, with errors of 0.7% and 4% from the calculated values ​​respectively, which are close to the calculated values. This proves the effectiveness of the present invention as a method for rapid ultrasonic scanning of components.

[0101] In summary, the present invention has the following advantages compared with the prior art:

[0102] The present invention provides an ultrasonic scanning imaging method and system for accurately locating the internal interface of a chip. By collecting parameter indicators such as the external dimensions in the destructive physical analysis (DFA) test of electronic components and the thickness dimensions and spacing in X-ray transmission measurement, combined with the focal length of the acoustic probe (i.e., transducer), the vertical position of the acoustic probe when the target layer is clearly imaged is calculated. Then, based on the principle of ultrasonic scanning, the approximate positions of the surface waves and the reflected waves from the chip layer are calculated, and the calculated parameters are used to select the reflected wave band, thereby enabling the ultrasonic scanning microscope to quickly locate the scanning imaging of a specific layer inside the chip, saving the time required for ultrasonic scanning in the DPA test of the integrated circuit electronic components to be tested, and improving the efficiency of ultrasonic scanning tests in the DPA test of integrated circuit electronic components.

[0103] It will be easily understood by those skilled in the art that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An ultrasonic scanning imaging method for accurately locating the internal interface of a chip, characterized in that: The following steps are involved: Perform visual inspection on the electronic components of the integrated circuit to be tested and obtain the thickness of the electronic components of the integrated circuit to be tested; Using X-rays to perform a side scan of the integrated circuit electronic component to be tested, locate the chip or substrate layer, and obtain the thickness of the packaging material; wherein the chip or substrate layer is encapsulated with the packaging material between the chip or substrate layer and the upper surface of the integrated circuit electronic component to be tested; Select the transducer according to the thickness of the integrated circuit electronic components to be tested; Obtaining the propagation speed of the ultrasonic wave in the packaging material and the test medium according to the packaging material and the ultrasonic scanning test medium; wherein the electronic component of the integrated circuit to be tested is placed in the test medium during the ultrasonic scanning imaging; Using the thickness of the packaging material, the focal length of the transducer, and the propagation speed of ultrasound in the packaging material and the test medium, and based on the principle of ultrasonic scanning imaging, calculate the height of the transducer probe from the top surface of the integrated circuit electronic component to be tested when the ultrasound is imaging at the chip layer or substrate layer; Calculate the distance between the probe and the bottom of the test medium based on the height of the probe from the upper surface of the electronic component of the integrated circuit to be tested and the thickness of the electronic component of the integrated circuit to be tested; Calculate the transit time of ultrasonic waves in the packaging material based on the propagation speed of ultrasonic waves in the packaging material and the thickness of the packaging material; The transit time of the ultrasonic wave in the test medium is calculated based on the propagation speed of the ultrasonic wave in the test medium and the height of the probe from the upper surface of the electronic component of the integrated circuit to be tested.

2. The ultrasonic scanning imaging method according to claim 1, characterized in that: The height WP of the probe from the upper surface of the integrated circuit electronic component to be tested is: WP=F-D(C tm / C w ) Where F is the focal length of the transducer; D is the thickness of the packaging material; the test medium is pure water; C tm and C w are the propagation speeds of ultrasonic waves in packaging materials and pure water, respectively.

3. The ultrasonic scanning imaging method according to claim 2, characterized in that: The distance between the probe and the bottom of the tank is: L=WP+T Wherein, WP is the height between the probe and the upper surface of the electronic component of the integrated circuit to be tested; T is the thickness of the electronic component of the integrated circuit to be tested.

4. The ultrasonic scanning imaging method according to claim 2 or 3, characterized in that: The transit time TOF1 of ultrasonic waves in the packaging material is: C tm TOF1=D 2 Among them, C tm is the speed of ultrasonic waves in the packaging material; D is the thickness of the packaging material; The transit time TOF2 of ultrasound in pure water is: C w TOF2=WP 2 Among them, C w is the propagation speed of ultrasound in water; WP is the height between the probe and the upper surface of the integrated circuit electronic component to be tested.

5. An ultrasonic scanning imaging system for accurately locating the internal interface of a chip, characterized in that: include: A microscope is used to visually inspect the electronic components of the integrated circuit to be tested and obtain the thickness of the electronic components of the integrated circuit to be tested; An X-ray detector is used to use X-rays to perform a side scan of the integrated circuit electronic component to be tested, locate the chip or substrate layer, and obtain the thickness of the packaging material; wherein the chip or substrate layer is encapsulated with a packaging material between the chip or substrate layer and the upper surface of the integrated circuit electronic component to be tested; A transducer is selected according to the thickness of the electronic component of the integrated circuit to be tested and is used for ultrasonic scanning imaging of the electronic component of the integrated circuit to be tested; a material acoustic impedance table storage module, configured to store the material acoustic impedance table and obtain the propagation velocity of the ultrasonic wave in the packaging material and the test medium according to the packaging material and the ultrasonic scanning test medium; wherein the electronic component of the integrated circuit to be tested is placed in the test medium during ultrasonic scanning imaging; The test medium tank is used to store the test medium and provide an ultrasonic test medium environment; it has built-in integrated circuit electronic components to be tested; The data processing module is used to calculate the height of the transducer probe from the upper surface of the electronic component of the integrated circuit to be tested when the ultrasonic wave is imaged on the chip layer or the substrate layer based on the thickness of the packaging material, the focal length of the transducer, and the propagation speed of the ultrasonic wave in the packaging material and the test medium, according to the principle of ultrasonic scanning imaging; and calculate the distance between the probe and the bottom of the test medium based on the height of the probe from the upper surface of the electronic component of the integrated circuit to be tested and the thickness of the electronic component of the integrated circuit to be tested; and calculate the transit time of the ultrasonic wave in the packaging material based on the propagation speed of the ultrasonic wave in the packaging material and the thickness of the packaging material; and calculate the transit time of the ultrasonic wave in the test medium based on the propagation speed of the ultrasonic wave in the test medium and the height of the probe from the upper surface of the electronic component of the integrated circuit to be tested.

6. The ultrasonic scanning imaging system according to claim 5, characterized in that: The height WP of the probe from the upper surface of the integrated circuit electronic component to be tested is: WP=F-D(C tm / C w ) Where F is the focal length of the transducer; D is the thickness of the packaging material; the test medium is pure water; C tm and C w are the propagation speeds of ultrasonic waves in packaging materials and pure water, respectively.

7. The ultrasonic scanning imaging system according to claim 6, characterized in that: The distance between the probe and the bottom of the tank is: L=WP+T Wherein, WP is the height between the probe and the upper surface of the electronic component of the integrated circuit to be tested; T is the thickness of the electronic component of the integrated circuit to be tested.

8. The ultrasonic scanning imaging system according to claim 6 or 7, characterized in that: The transit time TOF1 of ultrasonic waves in the packaging material is: C tm TOF1=D 2 Among them, C tm is the speed of ultrasonic waves in the packaging material; D is the thickness of the packaging material; The transit time TOF2 of ultrasound in pure water is: C w TOF2=WP 2 Among them, C w is the propagation speed of ultrasound in water; WP is the height between the probe and the upper surface of the integrated circuit electronic component to be tested.

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