Defect positioning method based on laser induction and X-ray imaging technology

Abstract

The invention relates to the technical field of detection, in particular to a defect positioning method based on laser induction and X-ray imaging technology, which comprises the following steps: carrying out current-voltage scanning on a sample to be tested to determine the withstand voltage and breakdown threshold voltage of the sample; carrying out defect detection on the sample by utilizing a laser-induced microscope, and determining a defect position and a defect type by detecting differential current change when laser irradiates a fault position; after the defect is determined, an X-ray imaging technology is used for integrally scanning the sample, the possible defect position of the sample is positioned and amplified on the basis of a laser-induced detection result, and the internal structure of the positioned and amplified sample is observed. The laser induction technology is used for rapidly determining the direction of the defect, the approximate position and range of the defect can be rapidly determined, then the X-ray imaging technology is used for accurately positioning the specific position of the defect, and through the combined use, the detection efficiency and the detection accuracy can be remarkably improved.

Description

Technical Field

[0001] The present invention relates to the field of detection technology, and in particular to a defect positioning method based on laser induction and X-ray imaging technology. Background Art

[0002] In the field of materials science and engineering, laser induction and X-ray imaging technologies are widely used for defect location. Laser induction technology uses a high-energy laser beam to generate thermal stimulation on the surface of the material and detects the response signal to identify and locate defects. X-ray imaging technology emits X-rays to penetrate the object being tested and receives images on the other side to detect internal structures and defects.

[0003] Laser induction technology uses a high-energy laser beam to generate thermal stimulation on the surface of the material, and identifies and locates defects by detecting the response signal. The advantage is that it does not cause damage to the material, can detect surface and internal defects, has high resolution, and is suitable for locating tiny defects.

[0004] A study proposed a binary classification detection method for metal AM component defects based on laser induction technology combined with machine learning algorithms, which achieved rapid classification of different component defect types. The disadvantage is that laser induction technology is limited to surface and near-surface defects, and has limited detection capabilities for defects buried deep inside the material, and is mainly suitable for surface and near-surface defects. If the sample is unopened or the defect is inside the sample, it will be difficult to locate the defect and it will be impossible to know what type of defect it is.

[0005] X-ray imaging is mainly used to detect internal structures and defects. Some studies have used the advantages of non-destructive and high collimation of X-ray imaging technology to conduct in-depth detection inside metal materials. However, it is not as sensitive as other detection methods for surface defects or tiny cracks. Summary of the invention

[0006] The purpose of the present invention is to overcome the above problems or at least partially solve the above problems, and to propose a defect location method based on laser induction and X-ray imaging technology.

[0007] To achieve the above object, the present invention provides the following technical solution: a defect location method based on laser induction and X-ray imaging technology, comprising the following steps:

[0008] Step 1: Perform a current-voltage scan on the sample to be tested to determine the withstand voltage and breakdown threshold voltage of the sample;

[0009] Step 2: Use a laser induced microscope to detect defects on the sample. When the laser irradiates the fault location, the defect location and defect type are determined by detecting the differential current change. After the laser is turned on, the DUT reflection image is focused and captured, and the auxiliary image of the DUT is taken to obtain the light emission site image of a single side of the sample. The laser sensitive part displayed is the defect location;

[0010] Step 3. After determining the type of defect, fix the sample on the test bench, adjust the position of the X-ray source and detector, use X-ray imaging technology to scan the sample as a whole, and based on the laser induced detection results, locate and magnify the possible defect positions of the sample, observe the internal structure of the sample under positioning and magnification, rotate the sample and stop at different angles to collect two-dimensional projection images, and combine multiple projection images to produce a three-dimensional reconstruction.

[0011] In a preferred embodiment, in step 2, if there is no obvious reaction, it is considered to be a short circuit defect, the sample is fixed on a platform, and a probe is used to apply voltage and current to it. After a certain voltage is applied to the sample, the current and the sample characterization light emission site image are observed.

[0012] In a preferred embodiment, in step 2, if no laser sensitive part is displayed after a certain voltage is applied to the sample, the normal and defective parts of the sample are determined by changing the position of the probe, and the defective parts are marked.

[0013] In a preferred embodiment, in step 2, the two probe positions are positions where positive and negative voltages are applied to the sample.

[0014] In a preferred embodiment, in step 2, if no current is displayed and no photons escape when the sample that has been determined to be damaged is pressurized in laser mode, it is preliminarily determined that it is not a short circuit fault, but a short circuit problem exists and the specific location of the short circuit defect cannot be obtained.

[0015] In a preferred embodiment, in step three, the X-ray microscope uses photons generated by an X-ray source to penetrate the sample to achieve full-field imaging of X-rays, and the detector collects signals of different absorption and presents the X-ray image with X-ray absorption contrast to obtain the three-dimensional tissue morphology of the sample and virtual two-dimensional slice tissue morphology information at different angles and positions.

[0016] In a preferred embodiment, in step three, the defect location of the broken fuse can be determined by three-dimensionally reconstructing the sample.

[0017] Compared with the prior art, the present invention has the following beneficial effects: using laser induction technology to quickly determine the direction of the defect, the approximate position and range of the defect can be quickly determined, providing basic information for subsequent precise positioning, thereby saving detection time, and then using X-ray imaging technology to accurately locate the specific position of the defect, and performing precise X-ray imaging of the identified defect area to obtain a high-resolution image, and accurately locate the specific position and type of the defect. Through this combined use, the detection efficiency and accuracy can be significantly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a flow chart of the present invention;

[0019] Figure 2 This is a graph showing the results of the laser induction test of the present invention;

[0020] Figure 3 The three-view imaging diagram of the fuse under the X-ray microscope of the present invention;

[0021] Figure 4 This is a three-dimensional image of the fuse under an X-ray microscope of the present invention. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] See also Figure 1-4 The present invention provides a technical solution: a defect location method based on laser induction and X-ray imaging technology, comprising the following steps:

[0024] Step 1: Perform a current-voltage scan on the fuse to determine the withstand voltage and breakdown threshold voltage of the fuse. When a voltage of 1V is applied, the current is 0.3nA. When a voltage of 10V is applied, the current is 10.9nA. The current will be detected only when it reaches the micron level, and the nanometer level current cannot be detected, so the fuse is determined to be open circuit.

[0025] Step 2: Use laser induced microscopy to detect defects on the fuse. The voltage value is 80kv, there is no filter, and the pixel size is 20.868um. After scanning 1301 images, reconstruct a three-dimensional model of the fuse. The laser induced microscope can monitor the power consumption changes caused by thermal stimulation. Local heating will cause resistance changes. When the laser irradiates the fault location, the defect location and defect type are determined by detecting the differential current change. The current will be detected only when it reaches the micron level, and the nanometer level current cannot be detected. After the laser is turned on, focus and capture the DUT reflection image, take the auxiliary image of the DUT to obtain the light emission site image of one side of the fuse, and the laser sensitive part displayed is the defect location;

[0026] If there is no obvious reaction, it may be a short circuit defect. Fix the fuse on the platform and use the probe to apply voltage and current to it. When a voltage of 1V is applied, the current is 0.3nA. When a voltage of 10V is applied, the current is 10.9nA. The nanometer-level current is considered as a short circuit. The two probe positions are the positions where the positive and negative voltages are applied to the fuse. After applying a certain voltage to the fuse, observe the current and the sample characterization light emission site image; if no laser sensitive part is displayed, the normal and defective parts of the fuse are determined by changing the probe position, and the defective parts are marked;

[0027] If no current is displayed and no photons escape when the fuse that has been confirmed to be damaged is pressurized in laser mode, it is initially determined that it is not a circuit breaker fault, but there is a circuit breaker problem and the specific location of the circuit breaker defect cannot be obtained, such as Figure 2 shown.

[0028] Step 3. After determining the defect, fix the fuse on the test bench, adjust the position of the X-ray source and the detector. The energy range of the X-ray source is 40-140kv, the detector lens has three magnifications of 0.4 times, 4 times, and 20 times, and the resolution reaches 900nm. Use X-ray imaging technology to scan the fuse as a whole, and based on the laser induced detection results, locate and magnify the possible defect positions of the fuse, and observe the internal structure of the sample under positioning and magnification. The X-ray microscope uses the photons generated by the X-ray source to penetrate the fuse to realize full-field imaging of X-rays. The detector collects signals with different absorption and presents the X-ray image with X-ray absorption contrast to obtain the three-dimensional tissue morphology of the fuse and the virtual two-dimensional slice tissue morphology information at different angles and positions. The fuse rotates and stops at different angles to collect two-dimensional projection images. Multiple projection images are combined to generate a three-dimensional reconstruction. The three-dimensional reconstruction of the fuse can determine the defect position of the fuse break, that is, the fuse break, such as Figure 3 and Figure 4 As shown, in Figure 4In the 3D image of the fuse, it can be seen that there are obvious fracture marks on the top of the fuse, so the defective position of the fuse can be determined.

[0029] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A defect location method based on laser induction and X-ray imaging technology, characterized in that: The following steps are involved: Step 1: Perform a current-voltage scan on the sample to be tested to determine the withstand voltage and breakdown threshold voltage of the sample; Step 2: Use a laser induced microscope to detect defects on the sample. When the laser irradiates the fault location, the defect location and defect type are determined by detecting the differential current change. After the laser is turned on, the DUT reflection image is focused and captured, and the auxiliary image of the DUT is taken to obtain the light emission site image of a single side of the sample. The laser sensitive part displayed is the defect location; Step 3. After determining the type of defect, fix the sample on the test bench, adjust the position of the X-ray source and detector, use X-ray imaging technology to scan the sample as a whole, and based on the laser induced detection results, locate and magnify the possible defect positions of the sample, observe the internal structure of the sample under positioning and magnification, rotate the sample and stop at different angles to collect two-dimensional projection images, and combine multiple projection images to produce a three-dimensional reconstruction.

2. The defect location method based on laser induction and X-ray imaging technology according to claim 1, characterized in that: In the step 2, if there is no obvious reaction, it is considered to be a short circuit defect. The sample is fixed on the platform, and a voltage and current are applied to it using a probe. After a certain voltage is applied to the sample, the current and the sample characterization light emission site image are observed.

3. The defect location method based on laser induction and X-ray imaging technology according to claim 2, characterized in that: In the step 2, if no laser sensitive part is displayed after a certain voltage is applied to the sample, the normal and defective parts of the sample are determined by changing the position of the probe, and the defective parts are marked.

4. The defect location method based on laser induction and X-ray imaging technology according to claim 3 is characterized in that: In step 2, the two probe positions are positions where positive and negative voltages are applied to the sample.

5. The defect location method based on laser induction and X-ray imaging technology according to claim 4 is characterized in that: In the step 2, if no current is displayed and no photons escape when the sample that has been confirmed to be damaged is pressurized in the laser mode, it is preliminarily determined that it is not a short circuit fault, but a short circuit problem exists and the specific location of the short circuit defect cannot be obtained.

6. The defect location method based on laser induction and X-ray imaging technology according to claim 5, characterized in that: In step three, the X-ray microscope uses photons generated by the X-ray source to penetrate the sample to achieve full-field X-ray imaging. The detector collects signals with different absorption and presents the X-ray image with X-ray absorption contrast to obtain the three-dimensional tissue morphology of the sample and virtual two-dimensional slice tissue morphology information at different angles and positions.

7. The defect location method based on laser induction and X-ray imaging technology according to claim 6, characterized in that: In the step three, the defect position of the broken fuse can be determined by three-dimensionally reconstructing the sample.

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