Positioning method and system for measuring failure point depth

Abstract

The present invention relates to a positioning method and system for measuring the depth of a failure point, including measuring the reference hot spots of a sample at different phase-locked frequencies to obtain at least one reference hot spot relationship curve; confirming the failure hot spots of the sample, measuring the failure hot spots of the sample at different phase-locked frequencies to obtain at least one failure hot spot relationship curve; comparing the reference hot spot relationship curve with the failure hot spot relationship curve to obtain the position information of the failure hot spot in the failure hot spot relationship curve relative to the reference hot spot in the reference hot spot relationship curve. Compared with the traditional electrical failure analysis method, the present invention has a higher degree of automation, and it no longer needs to obtain complex design information of electronic devices, avoiding the need to perform abnormal elimination confirmation layer by layer for 3D packaging products. It can quickly determine at which layer the chip has a problem through the depth information of the failure point.

Description

Technical Field

[0001] The present invention relates to the field of chip electrical failure analysis, and in particular to a positioning method and system for measuring the depth of a failure point. Background Art

[0002] With the development and progress of science and technology, the structure of electronic devices is becoming more and more complex, and their integration is getting higher and higher. As the number of transistors and chip layers per unit area of ​​electronic devices increases, the information required for failure analysis of the electrical performance of electronic devices is also increasing. For example, it is necessary to know the depth information of the failure point in the vertical direction, or know which layer of the chip fails.

[0003] At present, the traditional electrical failure analysis method usually uses the phase delay of the phase-locked infrared microscope (that is, the delay time between the square wave voltage applied to the electronic device sample and the infrared heat signal emitted by the sample) to perform in-depth analysis of the failure point. However, this electrical failure analysis method has the following problems:

[0004] (1) It is necessary to obtain the design information of each layer of the electronic device sample before analysis, such as the number of layers, material type, material thermal conductivity, material resistance, etc., which makes the analysis process complicated. In addition, the thermal conductivity of the material is different under different production and manufacturing process conditions, resulting in a large deviation between the failure point depth data results calculated based on the theoretical model and theoretical parameters and the actual depth position data, making it impossible to accurately locate the failure point at the depth of the electronic device.

[0005] (2) Under different phase-locked frequencies, the initial delay time of the square wave voltage applied to the electronic device sample for the infrared heat signal emitted by the sample is inconsistent, resulting in the measured signal also including the delay time of the voltage generated by the power supply, making the calculated data inaccurate.

[0006] (III) When mass-producing end-user products, if the internal circuit of the product is short-circuited, it is impossible to distinguish whether it is the chip itself or the packaging that is wrong. For 3D packaged products, finding the failure point requires the use of tangents to eliminate the abnormality layer by layer, which is time-consuming and laborious. Summary of the invention

[0007] In view of the above-mentioned shortcomings of the prior art, an object of the present invention is to provide a positioning method and system for measuring the depth of a failure point, so as to solve one or more problems in the prior art.

[0008] To achieve the above object, the technical solution of the present invention is as follows:

[0009] A positioning method and system for measuring the depth of a failure point includes the following steps:

[0010] Measuring reference heating points of the sample at different phase-locked frequencies to obtain at least one relationship curve of the reference heating points;

[0011] Confirm the failure hotspot of the sample, and measure the failure hotspot of the sample at different phase-locked frequencies to obtain at least one failure hotspot relationship curve;

[0012] The reference hot spot relationship curve is compared with the failure hot spot relationship curve to obtain the position information of the failure hot spot in the failure hot spot relationship curve relative to the reference hot spot in the reference hot spot relationship curve.

[0013] Furthermore, the step of obtaining the reference heating point relationship curve includes the following steps:

[0014] placing the sample in the measuring cell;

[0015] Select the reference hot spot;

[0016] Different phase-locked frequencies are configured to measure the reference heating point, obtain the intensity information of the reference heating point under different phase-locked frequencies, and obtain the relationship curve of the reference heating point relative to the phase-locked frequency according to the intensity information of different reference heating points under different phase-locked frequencies.

[0017] Furthermore, the configuration of the phase-locked frequency includes the following steps:

[0018] Choose different phase-locked frequencies;

[0019] The phase-locked frequency is converted into a control signal and sent to the measuring unit to adjust the phase-locked frequency output by the measuring unit.

[0020] Furthermore, the maximum value of the phase-locked frequency does not exceed 1 / 4 of the frame rate of the measurement unit, and the minimum value of the phase-locked frequency is not greater than 1 Hz.

[0021] Further, the position information of the failure hot spot in the failure hot spot relationship curve relative to the reference heating point in the reference heating point relationship curve includes that the failure hot spot relationship curve is located between adjacent reference heating point relationship curves.

[0022] Furthermore, the position information includes that the failure hot spot relationship curve is located outside any reference hot spot relationship curve.

[0023] Accordingly, the present invention also provides a system using the positioning method for measuring the depth of a failure point, comprising:

[0024] A signal unit, the signal unit is used to generate electrical signals with different phase-locked frequencies;

[0025] A measuring unit, the measuring unit is used to apply electrical signals of different phase-locked frequencies to the sample, so that the sample is stimulated by the electrical signal and emits an infrared signal;

[0026] A collection unit, the collection unit is used to collect infrared signals released by the reference heating point or the failure heating point;

[0027] A calculation unit, wherein the calculation unit generates a reference hot spot relationship curve according to the infrared signal released by the reference hot spot, and generates a failure hot spot relationship curve according to the infrared signal released by the failure hot spot, and compares the reference hot spot relationship curve with the failure hot spot relationship curve to obtain position information of the failure hot spot in the failure hot spot relationship curve relative to the reference hot spot in the reference hot spot relationship curve.

[0028] A computer device comprises a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the method when executing the computer program.

[0029] A computer-readable storage medium stores a computer program, which implements the steps of the method when executed by a processor.

[0030] Compared with the prior art, the beneficial technical effects of the present invention are as follows

[0031] The present invention measures each reference heating point through different phase-locked frequencies to obtain the intensity information of the reference heating point under different phase-locked frequencies, and obtains the relationship curve of the reference heating point relative to the phase-locked frequency according to the intensity information of different reference heating points under different phase-locked frequencies; similarly, by confirming the failure hotspot of the sample and measuring the intensity information of the failure hotspot of the sample at different frequencies, at least one relationship curve of the failure hotspot is obtained, and by comparing the relationship curve of the failure hotspot with the relationship curve of the reference heating point relative to the phase-locked frequency, the position information of the failure hotspot in the failure hotspot relationship curve relative to the reference heating point in the reference heating point relationship curve is obtained, that is, the depth information of the failure point is obtained.

[0032] Compared with the traditional electrical failure analysis method, the present invention has a higher degree of automation. It no longer needs to obtain complex design information of electronic devices, and avoids the need to confirm abnormalities layer by layer for 3D packaging products. It can quickly determine which layer of the chip has problems through the depth information of the failure point. In addition, the present invention is different from the traditional method of fitting by combining phase information with material properties. It is no longer limited by the difference in sample materials, which reduces the error and effectively improves the accuracy of the positioning results. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 The present invention shows a positioning method for measuring the depth of a failure point and a schematic diagram of a relationship curve between a reference heating point and a phase-locked frequency and a relationship curve between a failure heating point and a phase-locked frequency in a system.

[0034] Figure 2 The present invention shows a method for measuring the depth of a failure point and a schematic diagram of the structure of a positioning system for measuring the depth of a failure point in a system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical scheme and advantages of the present invention clearer, the positioning method and system for measuring the depth of the failure point proposed by the present invention are further described in detail in combination with the accompanying drawings and specific embodiments. According to the following description, the advantages and features of the present invention will be clearer. It should be noted that the accompanying drawings are in a very simplified form and use non-precise proportions, which are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention. In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, please refer to the accompanying drawings. It should be noted that the structure, proportion, size, etc. illustrated in the accompanying drawings of this specification are only used to match the content disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no technical substantive significance. Any modification of the structure, change of the proportional relationship or adjustment of the size, without affecting the effect that the present invention can produce and the purpose that can be achieved, should still fall within the scope of the technical content disclosed by the present invention.

[0036] Embodiment 1:

[0037] The present application provides a positioning method for measuring the depth of a failure point, which can be applied to Figure 2 In the system shown, specifically, the system includes a signal unit 100, a measuring unit 200, a collecting unit 300 and a calculating unit 400. Specifically, the signal unit 100 is used to generate electrical signals of different phase-locked frequencies, and the signal unit can be a signal generator in this embodiment. The measuring unit 200 is used to receive and apply electrical signals of different phase-locked frequencies to the sample, so that the sample is stimulated by the electrical signal and releases an infrared signal. Preferably, the measuring unit is a phase-locked infrared camera. The collecting unit 300 is used to collect infrared signals released by reference hot spots or failure hot spots in the sample, and the collecting unit 300 is preferably a data acquisition card. The calculating unit 400 is used to collect the infrared signals, and generate a reference hot spot relationship curve according to the infrared signals released by the reference hot spots, and generate a failure hot spot relationship curve according to the infrared signals released by the failure hot spots, and compare the reference hot spot relationship curve with the failure hot spot relationship curve to obtain the position information of the failure hot spot in the failure hot spot relationship curve relative to the reference hot spot in the reference hot spot relationship curve. Preferably, the calculating unit 400 is preferably any one of a computer, a smart phone or a tablet computer.

[0038] The positioning method for measuring the failure point depth includes the following steps:

[0039] Step S1: Measure the reference heating points of the sample at different frequencies to obtain at least one reference heating point relationship curve. For details, please refer to Figure 1 In the first embodiment, there are two reference heating point relationship curves, namely Ref1 and Ref3.

[0040] The acquisition of the relationship curve of the reference heating point includes the following steps:

[0041] S100: Place the sample in the measuring unit 200, ensure that the sample surface is flat and clean, and then place the sample on the sample stage of the measuring unit 200. In this step, the sample can be an electronic component in the production process or in the use process, such as a MOS tube, an IGBT tube or a metal wire. Then configure the power supply. In this embodiment, the maximum value of the power supply is set to 1V, the minimum value of the power supply is set to 0V, the power supply threshold is 0.001A, and the measurement delay is set to 5s.

[0042] S101: Select the reference hot spot position. Specifically, confirm the position of the reference hot spot through the phase-locking technology, open the software and circle the position of the reference hot spot, specifically, select the reference hot spot position in the software interface. The position of the reference hot spot is confirmed by scanning the sample surface to obtain the response signal of each scanning point, and output the phase and amplitude information of the scanning point. By comparing the phase and amplitude of different scanning points, if the phase and / or amplitude of a certain scanning point changes significantly relative to other scanning points, for example, a bright spot appears in a certain scanning point, and the phase diagram converges in the region, showing regionalization, then the scanning point is the reference hot spot, and the reference hot spot includes X-coordinate information and Y-coordinate information. Assuming that the initial phase-locking frequency is set to 0.5Hz, a square wave signal is passed into the sample, so that the reference hot spots at different positions of the sample are excited by current and release infrared signals.

[0043] S102: Obtain each reference heating point through the measurement unit 200, capture the infrared radiation image of the reference heating point on the sample surface, and record the intensity information under the reference heating point, such as Figure 1 As shown, when the phase-locked frequency is 0.5 Hz, the intensity value of the reference heating point A1 is 100.

[0044] S103: adjusting different phase-locked frequencies in turn to measure each reference heating point, obtaining the intensity information of the reference heating point under different phase-locked frequencies, and obtaining a relationship curve of the reference heating point relative to the phase-locked frequency according to the intensity information of different reference heating points under different phase-locked frequencies.

[0045] like Figure 1As shown, for example, when the phase-locking frequency is 2.5 Hz, the intensity value of the corresponding reference heating point A2 is 80, when the phase-locking frequency is 6 Hz, the intensity value of the corresponding reference heating point A3 is 60, when the phase-locking frequency is 12.5 Hz, the intensity value of the corresponding reference heating point A4 is 40, when the phase-locking frequency is 25 Hz, the intensity value of the corresponding reference heating point A5 is 15, and finally, the intensity values ​​are summarized to obtain the relationship curve of the reference heating point of this layer relative to the phase-locking frequency, which is recorded as Ref1( Figure 1 The gray curve in the middle) is transmitted to the calculation unit 400.

[0046] Furthermore, the adjustment of the phase-locked frequency includes the following steps:

[0047] Start the software supporting the measurement unit 200;

[0048] Configure different phase-locked frequencies in the software interface, for example, select phase-locked frequencies of 2.5Hz, 6Hz, 12.5Hz, and 25Hz;

[0049] The phase-locked frequency is converted into a control signal and sent to the measuring unit 200 to adjust the phase-locked frequency output by the measuring unit 200 .

[0050] Furthermore, the maximum value of the phase-locked frequency does not exceed 1 / 4 of the frame frequency of the measurement unit, and the minimum value of the phase-locked frequency does not exceed 1 Hz.

[0051] S104: Repeat the above steps S100 to S103 to obtain the relationship curve between the reference heating point and the phase-locked frequency, that is, complete the modeling of the reference heating point curve, and record it as Ref3 (please refer to Figure 1 Blue curve) and transmitted to the calculation unit 400. In the Ref3 relationship curve, when the phase-locked frequency is 0.5Hz, the intensity value of the reference heating point B1 is 140, when the phase-locked frequency is 2.5Hz, the intensity value of the reference heating point B2 is 120, when the phase-locked frequency is 6Hz, the intensity value of the corresponding reference heating point B3 is recorded as 100, when the phase-locked frequency is 12.5Hz, the intensity value of the corresponding reference heating point B4 is recorded as 80, and when the phase-locked frequency is 25Hz, the intensity value of the corresponding reference heating point B5 is recorded as 52.

[0052] S2: Confirm the failure hotspot of the sample and measure the intensity information of the failure hotspot of the sample at different frequencies to obtain at least one relationship curve of the failure hotspot. The specific process is as follows:

[0053] Through the measurement of different phase-locking frequencies, the failure hotspot C1 of the sample is confirmed, a 0Hz phase-locking frequency is introduced at the failure hotspot C1, and the intensity value of the corresponding failure hotspot C1 is recorded as 135Hz. Continue to adjust different phase-locking frequencies. For example, when the phase-locking frequency is 2.5Hz, the intensity value of the corresponding reference hot spot C2 is 115. When the phase-locking frequency is 6Hz, the intensity value of the corresponding reference hot spot C3 is recorded as 96. When the phase-locking frequency is 12.5Hz, the intensity value of the corresponding reference hot spot C4 is recorded as 77. When the phase-locking frequency is 25Hz, the intensity value of the corresponding reference hot spot C5 is recorded as 55. Finally, the intensity values ​​are summarized to obtain the intensity-phase-locking frequency relationship curve of the failure hot spot of this layer, that is, the modeling of the failure hot spot relationship curve is completed and recorded as Fail2 (please refer to Figure 1 Purple curve) and transmitted to the calculation unit 400. The confirmation of the failure hotspot of the sample can be specifically to compare the excellent sample and the bad sample, wherein the excellent sample is the sample whose leakage value is within the specified range, and the bad sample is the sample whose leakage value exceeds the specified range, and it is necessary to determine which leakage causes the sample with a large value through analysis means.

[0054] S3: Compare the reference hot spot relationship curve with the failure hot spot relationship curve to obtain the position information of the failure hot spot in the failure hot spot relationship curve relative to the reference hot spot in the reference hot spot relationship curve. Specifically, according to Figure 1 As shown, the failure hotspot relative to the phase-locked frequency relationship curve Fail2 is located between the reference hot spot relative to the phase-locked frequency relationship curve Ref1 and the reference hot spot relative to the phase-locked frequency relationship curve Ref3, and the failure hotspot relative to the phase-locked frequency relationship curve Fail2 is closer to the reference hot spot relative to the phase-locked frequency relationship curve Ref3, and the depth of the failure hotspot is obtained, that is, the depth of the failure hotspot is located between the first layer chip and the third layer chip.

[0055] Embodiment 2:

[0056] The steps of the second embodiment are the same as those of the first embodiment, except that the relationship curve of the reference heating point relative to the phase-locked frequency in the second embodiment is Ref2 (please refer to Figure 1 red curve) and the relationship curve of the reference heating point relative to the phase-locked frequency Ref3 (please refer to Figure 1 The blue curve) and the relationship curve of the failure hotspot relative to the phase-locked frequency of the second embodiment are Fail1 (please refer to Figure 1 green curve) or the relationship curve between the failure hotspot and the phase-locked frequency Fail2 (please refer to Figure 1 Purple curve), that is, the failure hotspot relationship curve is outside any reference hotspot relationship curve, with the failure hotspot relationship curve Fail1 (please refer to Figure 1Green curve) as an example, its reference heating point relative to the phase-locked frequency curve Ref3 (please refer to Figure 1 The blue curve is outside the third-layer chip and far away from the reference heating point relative to the phase-locked frequency relationship curve Ref3, that is, the depth of the failure hotspot is outside the third-layer chip.

[0057] In addition, if the failure hotspot relationship curve Fail2 is taken as an example, it is between the reference hotspot relative to the phase-locked frequency relationship curve Ref1 and the reference hotspot relative to the phase-locked frequency relationship curve Ref3, that is, the depth of the failure hotspot is located between the second layer chip and the third layer chip.

[0058] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0059] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A positioning method for measuring the depth of a failure point, characterized in that The steps include: Measuring reference heating points of the sample at different phase-locked frequencies to obtain at least one relationship curve of the reference heating points; Confirm the failure hotspot of the sample, and measure the failure hotspot of the sample at different phase-locked frequencies to obtain at least one failure hotspot relationship curve; The reference hot spot relationship curve is compared with the failure hot spot relationship curve to obtain the position information of the failure hot spot in the failure hot spot relationship curve relative to the reference hot spot in the reference hot spot relationship curve.

2. The positioning method for measuring the failure point depth according to claim 1, characterized in that: The step of obtaining the reference heating point relationship curve includes the following steps: placing the sample in the measuring cell; Select the reference hot spot; Different phase-locked frequencies are configured to measure the reference heating point, obtain the intensity information of the reference heating point under different phase-locked frequencies, and obtain the relationship curve of the reference heating point relative to the phase-locked frequency according to the intensity information of different reference heating points under different phase-locked frequencies.

3. The positioning method for measuring the failure point depth according to claim 2, characterized in that: The configuration of the phase-locked frequency comprises the following steps: Choose different phase-locked frequencies; The phase-locked frequency is converted into a control signal and sent to the measuring unit to adjust the phase-locked frequency output by the measuring unit.

4. The positioning method for measuring the failure point depth according to claim 3, characterized in that: The maximum value of the phase-locked frequency does not exceed 1 / 4 of the frame rate of the measurement unit, and the minimum value of the phase-locked frequency does not exceed 1 Hz.

5. The positioning method for measuring the depth of a failure point according to claim 1, characterized in that: The position information of the failure hot spot in the failure hot spot relationship curve relative to the reference heating point in the reference heating point relationship curve includes that the failure hot spot relationship curve is located between adjacent reference heating point relationship curves.

6. The positioning method for measuring the depth of a failure point according to claim 1, characterized in that: The position information includes that the failure hot spot relationship curve is located outside any reference hot spot relationship curve.

7. A system using the positioning method for measuring the depth of a failure point according to any one of claims 1 to 6, characterized in that include: A signal unit, the signal unit is used to generate electrical signals with different phase-locked frequencies; A measuring unit, the measuring unit is used to apply electrical signals of different phase-locked frequencies to the sample, so that the sample is stimulated by the electrical signal and emits an infrared signal; A collection unit, the collection unit is used to collect infrared signals released by the reference heating point or the failed heating point; A calculation unit, wherein the calculation unit generates a reference hot spot relationship curve according to the infrared signal released by the reference hot spot, and generates a failure hot spot relationship curve according to the infrared signal released by the failure hot spot, and compares the reference hot spot relationship curve with the failure hot spot relationship curve to obtain position information of the failure hot spot in the failure hot spot relationship curve relative to the reference hot spot in the reference hot spot relationship curve.

8. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 6 are implemented.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

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