CN112285611A - Device Failure Location Analysis Method - Google Patents

Abstract

The present application relates to the technical field of failure analysis, and specifically discloses a device failure analysis and positioning method, including: calibrating a scanning probe to obtain calibration data; controlling the scanning probe to scan the device under test, and obtaining first parameter information, first parameter information Used to characterize the electromagnetic field information of the device under test scanning height plane; according to the first parameter information and calibration data, determine the electromagnetic field information of the device under test target height plane; according to the electromagnetic field information of the device under test target height plane, determine the surface of the device under test Electrical distribution: According to the electrical distribution on the surface of the device to be tested, determine the failure position of the device to be tested. Based on the principle of electromagnetic injection and detection, combined with the electromagnetic field information on the surface of the device under test, the failure position of the device under test can be analyzed. Compared with the traditional failure analysis method, the cost is lower, and the device under test does not need to be damaged. The overall failure The positioning method is highly reliable.

Description

Device Failure Location Analysis Method

technical field

The invention relates to the technical field of failure analysis, in particular to a device failure location analysis method.

Background technique

With the development of science and technology, electronic devices are gradually showing a trend of miniaturization. Correspondingly, the failure localization methods for electronic devices are becoming more and more complex. The traditional methods of failure localization mainly include X-ray technology, synchronous thermal emission technology, Magnetic microscopy and FIB analysis.

Among them, X-ray technology is a method of detecting internal defects of samples by using different attenuation coefficients of different materials of samples through X-ray perspective technology; synchronous thermal emission technology is to locate and analyze by detecting hot spots, such as metal wire short circuit, oxide layer Breakdown and damage and other failures; the magnetic microscopic defect localization technology uses a magnetic microscope to locate defects, and analyzes the magnetic field on the surface of the device to determine the failure location of the device; FIB (focused ion beam) analysis technology uses electrical transmission. Focus the ion beam into a very small ion beam to bombard the surface of the material, realize the stripping, deposition, implantation, cutting and modification of the material, prepare the defect metallographic cross section to analyze the failure mechanism, and find out the cause and location of the device failure.

Although the above failure location analysis methods can realize the failure analysis of electronic devices, they all have certain defects. For example, the magnetic microscopic defect location technology needs to use low temperature superconductivity measurement, which is expensive; It is necessary to destroy the electronic devices and so on.

Based on this, how to realize low-cost and high-reliability device failure location analysis is one of the technical problems that needs to be solved urgently in the art.

SUMMARY OF THE INVENTION

Based on this, it is necessary to provide a device failure location analysis method for the problem of how to achieve low-cost and high-reliability device failure location analysis.

A device failure location analysis method, the device failure location analysis method is based on a near-field detection system, the near-field detection system includes a scanning probe and a signal analysis device, and the scanning probe is used to perform a near-field on the device under test. scanning, the signal analysis device is used for injecting a signal into the device under test, and analyzing the signal generated by the scanning of the scanning probe; the device failure locating method includes:

Calibrating the scanning probe to obtain calibration data;

Controlling the scanning probe to scan the device under test, and obtaining first parameter information, where the first parameter information is used to characterize the electromagnetic field information of the device under test scanning height plane;

According to the first parameter information and the calibration data, determine the electromagnetic field information of the target height plane of the device under test;

According to the electromagnetic field information of the target height plane of the device under test, determine the electrical distribution on the surface of the device under test;

The failure position of the device under test is determined according to the electrical distribution on the surface of the device under test.

In one embodiment, the step of calibrating the scanning probe and acquiring calibration data includes:

The electromagnetic field information of the calibration device at the target height plane is obtained by simulation;

controlling the scanning probe to scan the calibration device to obtain second parameter information, where the second parameter information is used to characterize the electromagnetic field information of the calibration device in the scanning height plane;

The step of determining the electromagnetic field information of the target height plane of the device under test according to the first parameter information and the calibration data includes:

According to the first parameter information, the second parameter information and the electromagnetic field information of the calibration device at the target height plane, the electromagnetic field information of the device under test at the target height plane is obtained.

In one of the embodiments, the step of obtaining the electromagnetic field information of the device under test at the target height plane according to the first parameter information, the second parameter information and the electromagnetic field information of the calibration device at the target height plane include:

Perform PWS domain transformation on the first parameter information to obtain first frequency domain information, perform PWS domain transformation on the second parameter information to obtain second frequency domain information, and perform simulation on the electromagnetic field of the calibration device at the target height plane. The information is transformed in the PWS domain to obtain the third frequency domain information;

According to the first frequency domain information, the second frequency domain information and the third frequency domain information, obtain fourth frequency domain information corresponding to the electromagnetic field information of the target height plane of the device under test;

Perform inverse PWS domain transformation on the fourth frequency domain information to obtain electromagnetic field information on the target height plane of the device under test.

In one embodiment, the first frequency domain information corresponding to the electromagnetic field information of the target height plane of the device under test is obtained according to the first frequency domain information, the second frequency domain information and the third frequency domain information The steps of four frequency domain information include:

The fourth frequency domain information corresponding to the electromagnetic field information of the target height plane of the device under test is obtained by the following formula:

为所述待测器件目标高度z_j平面的电磁场信息所对应的第四频域信息，

为仿真获得的校准器件在目标高度z_j平面的电磁场信息所对应的第三频域信息，

为所述校准器件扫描高度z_i平面的电磁场信息所对应的第二频域信息，

为所述待测器件扫描高度z_i平面的电磁场信息所对应的第一频域信息。in,

is the fourth frequency domain information corresponding to the electromagnetic field information of the target height z _j plane of the device under test,

is the third frequency domain information corresponding to the electromagnetic field information of the calibration device at the target height z _j plane obtained by simulation,

the second frequency domain information corresponding to the electromagnetic field information of the scanning height _zi plane for the calibration device,

First frequency domain information corresponding to the electromagnetic field information of the scanning height _zi plane for the device under test.

In one of the embodiments, the electromagnetic field information includes magnetic field strength information;

The step of determining the electrical distribution on the surface of the device under test according to the electromagnetic field information of the target height plane of the device under test includes:

According to the magnetic field intensity information of the target height plane of the device under test, the current components in the X-axis direction and the Y-axis direction of the surface of the device under test are obtained;

The positional distribution of the surface current density on the surface of the device to be tested is determined according to the current components in the X-axis direction and the Y-axis direction of the surface of the device to be tested.

In one of the embodiments, the electromagnetic field information includes electric field strength information;

The step of determining the electrical distribution on the surface of the device under test according to the electromagnetic field information of the target height plane of the device under test includes:

According to the electric field intensity information of the target height plane of the device under test, the surface charge distribution on the surface of the device under test is determined.

In one embodiment, the step of determining the failure position of the device under test according to the electrical distribution on the surface of the device under test includes:

Determine the trajectory of the current signal injected into the device under test according to the positional distribution of the surface current density on the surface of the device under test;

According to the trajectory of the current signal, determine the standing wave current distribution curve;

The standing wave current distribution curve is fitted to determine the position of the open-circuit failure of the device under test.

In one embodiment, the step of determining the failure position of the device under test according to the electrical distribution on the surface of the device under test further includes:

According to the surface charge distribution on the surface of the device under test, determine the trajectory of the current signal injected into the device under test;

According to the trajectory of the current signal, determine the standing wave current distribution curve;

The standing wave current distribution curve is fitted to determine the short-circuit failure position of the device under test.

In one of the embodiments, the step of fitting the standing wave current distribution curve includes:

The standing wave current distribution curve is fitted by the following fitting formula:

Among them, I is the current signal, z is the distance of the current signal from the failure position, β is the phase constant, Z ₀ is the characteristic impedance, and P _RF is the incident power.

In one embodiment, after the step of determining the electromagnetic field information of the target height plane of the device under test according to the first parameter information and the calibration data, the device failure location analysis method further includes:

The failure position of the device under test is determined by comparing the electromagnetic field distribution diagram of the target height plane of the device under test with the electromagnetic field distribution diagram of the target height plane of the good device.

The above-mentioned device failure location analysis method is based on the near-field detection system. First, the scanning probe of the near-field detection system is calibrated to obtain calibration data; then the scanning probe is controlled to scan the device under test, and the electromagnetic field characterizing the device under test in the scanning height plane is obtained. Then, according to the first parameter information and calibration data, determine the electromagnetic field information of the target height plane of the device under test, and then determine the electrical distribution on the surface of the device under test; finally, according to the electrical distribution on the surface of the device under test, determine the failure location of the test device. That is, based on the principle of electromagnetic injection and detection, combined with the electromagnetic field information on the surface of the device under test, the failure position analysis of the device under test is realized. Compared with the traditional failure analysis method, the cost is lower, and the device under test does not need to be damaged. The overall failure localization method has high reliability.

Description of drawings

FIG. 1 is a schematic structural diagram of a near-field detection system provided by an embodiment of the present application;

2 is a flowchart of a method for locating a device failure provided by an embodiment of the present application;

3 is a schematic diagram of different height planes involved in the device failure location analysis method provided by the embodiment of the present application;

FIG. 4 is a flowchart of step S100 in the device failure location analysis method provided by the embodiment of the present application;

FIG. 5 is a flowchart of step S301 in the device failure location analysis method provided by the embodiment of the present application;

6 is a flowchart of step S400 in the device failure location analysis method provided by the embodiment of the present application;

7 is a flowchart of step S500 in the device failure location analysis method provided by the embodiment of the present application;

8 is a schematic diagram of a standing wave current distribution curve in a device failure location analysis method provided by an embodiment of the present application;

FIG. 9 and FIG. 10 are electromagnetic field distribution diagrams of a good device and a device under test in the device failure location analysis method provided by the embodiment of the present application.

Detailed ways

In order to facilitate understanding of the present invention, the present invention will be described more fully hereinafter with reference to the related drawings. Preferred embodiments of the invention are shown in the accompanying drawings. However, the present invention may be embodied in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the present disclosure will be more thorough and complete.

In the present invention, unless otherwise expressly specified and limited, the terms "installed", "connected", "connected", "fixed" and other terms should be understood in a broad sense, for example, it may be a fixed connection or a detachable connection , or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between the two elements, unless otherwise specified limit. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

The terms "first" and "second" are only used for descriptive purposes, and should not be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature delimited with "first", "second" may expressly or implicitly include at least one of that feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise expressly and specifically defined.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terms used herein in the description of the present invention are for the purpose of describing specific embodiments only, and are not intended to limit the present invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

At present, the common device failure analysis methods mainly use X-ray analysis technology, synchronous thermal emission technology, magnetic microscopy technology and FIB analysis technology. Among them, X-ray analysis technology is a fluoroscopy technology using X-rays, and a method of detecting the internal defects of the sample by using the different attenuation coefficients of different materials of the sample. The attenuation degree is related to the material, thickness and density of the sample. The intensity of the sample decays exponentially with the absorption coefficient and thickness of the material, forming images of the internal structure and defects of the material corresponding to different grayscales. Synchronous thermal emission technology locates and analyzes failures such as metal wire short circuit, oxide layer breakdown, damage, etc. by detecting hot spots. Magnetic microscopy uses a magnetic microscope to locate defects, and analyzes the magnetic field on the surface of the device to determine the failure location of the device. FIB (Focused Ion Beam) defect analysis technology is to use electric transmission to focus the ion beam into a very small ion beam to bombard the surface of the material, to achieve material stripping, deposition, implantation, cutting and modification, in many failure analysis In the case, it is necessary to prepare the defect metallographic cross section to analyze the failure mechanism and find out the cause and location of the device failure.

Although all of the above failure analysis methods can achieve device failure analysis, they are either costly, require damage to the device itself, or are not suitable for failure analysis of large-scale devices.

In view of the above problems, the present application is different from traditional failure analysis methods, and provides a device failure location analysis method with low cost, suitable for large-scale devices and high reliability based on the principle of electromagnetic near-field detection.

A device failure location analysis method provided in this application is based on a near-field detection system, and the near-field detection system is first introduced.

As shown in FIG. 1 , the near-field detection system in this application includes a scanning probe and a signal analysis device. The scanning probe is used for near-field scanning of the device under test, the signal analysis device is used for injecting signals into the device under test, and the scanning probe is used to analyze Scan the resulting signal.

The scanning probe is a near-field probe, which may include a composite probe and a single probe. The signal analysis equipment may include a network analyzer, the port of the network analyzer can be connected to the failed pin of the device under test by pinning or welding, and a current signal can be injected into the failed pin of the device under test through the port of the network analyzer. The near-field probe is connected to the network analyzer, and is used to scan the device under test in the near field and generate an electrical signal. After the network analyzer receives the electrical signal, it analyzes it, and then the corresponding electromagnetic field information can be obtained. During the scanning process, the near-field probe does not touch the surface of the device to be tested, and maintains a small distance, such as 100 μm, from the surface of the device to be tested.

In addition, a signal source for injecting a current signal into the failed pin of the device under test can also be set separately, that is, the signal analysis device and the signal source for analyzing the signal generated by the scanning probe are set separately.

As shown in FIG. 2 , the device failure location method provided by the present application includes the following steps:

Step S100, calibrating the scanning probe to obtain calibration data.

Before scanning and detecting the device under test, the scanning probe is first calibrated to obtain calibration data, so as to analyze the electromagnetic field information on the surface of the device under test in combination with the calibration data later.

Step S200 , controlling the scanning probe to scan the device under test, and obtaining first parameter information, where the first parameter information is used to represent the electromagnetic field information of the scanning height plane of the device under test.

After the scanning probe is calibrated, the device under test can be scanned by the scanning probe, that is, the scanning probe is controlled to scan a plane with a preset height above the surface of the device under test, which is defined as the scanning height plane in this application. When the signal analysis device obtains the electrical signal generated by the scanning probe, the first parameter information can be obtained by analysis, wherein the first parameter information is used to characterize the electromagnetic field information of the scanning height plane of the device under test.

Step S300: Determine the electromagnetic field information of the target height plane of the device under test according to the first parameter information and the calibration data.

The target height plane refers to a plane with a certain height from the surface of the device under test. After the first parameter information and calibration data are obtained, the electromagnetic field of the target height plane of the device under test can be obtained according to the first parameter information and calibration data. information.

Step S400: Determine the electrical distribution on the surface of the device to be tested according to the electromagnetic field information of the target height plane of the device to be tested.

After acquiring the electromagnetic field information of the target height plane of the device under test, the electrical distribution on the surface of the device under test can be determined accordingly, wherein the electrical distribution can include the position distribution of the surface current density and/or the surface charge distribution, etc.

Step S500 , determining the failure position of the device under test according to the electrical distribution on the surface of the device under test.

The above-mentioned device failure location analysis method is based on the near-field detection system. First, the scanning probe of the near-field detection system is calibrated to obtain calibration data; then the scanning probe is controlled to scan the device under test, and the electromagnetic field characterizing the device under test in the scanning height plane is obtained. Then, according to the first parameter information and calibration data, determine the electromagnetic field information of the target height plane of the device under test, and then determine the electrical distribution on the surface of the device under test; finally, according to the electrical distribution on the surface of the device under test, determine the failure location of the test device. That is, based on the principle of electromagnetic injection and detection, combined with the electromagnetic field information on the surface of the device under test, the failure position analysis of the device under test is realized. Compared with the traditional failure analysis method, the cost is lower, and the device under test does not need to be damaged. The overall failure localization method has high reliability. In addition, the device failure location analysis method provided in the present application can be applied to the failure location analysis of large-scale devices.

As shown in FIG. 4 , in one embodiment, step S100, that is, calibrating the scanning probe, and the step of acquiring calibration data includes the following steps:

Step S101 , obtain electromagnetic field information of the calibration device on the target height plane through simulation.

Specifically, a computer simulation method such as HFSS simulation can be used to obtain the electromagnetic field information of the calibration device at the target height Z _j plane. In this embodiment, the electromagnetic field information may include electric field strength information and/or magnetic field strength information.

Step S102 , controlling the scanning probe to scan the calibration device to obtain second parameter information, where the second parameter information is used to characterize the electromagnetic field information of the calibration device in the scanning height plane.

Using the aforementioned near-field detection system, configure calibration devices, signal analysis equipment and scanning probes. The scanning probe is controlled to scan the calibration device, and the signal analysis device acquires the electrical signal generated by the scanning probe, and analyzes to obtain the second parameter information. The second parameter information is a signal analysis device, such as a parameter that can be directly measured by a network analyzer according to an electrical signal generated by a scanning probe, which is used to characterize the electromagnetic field information of the calibration device at the scanning height plane.

In one embodiment, step S300, that is, the step of determining the electromagnetic field information of the target height plane of the device under test according to the first parameter information and the calibration data includes the following steps:

Step S301 , according to the first parameter information, the second parameter information, and the electromagnetic field information of the calibration device on the target height plane, obtain the electromagnetic field information of the device under test at the target height plane.

When the first parameter information used to characterize the electromagnetic field information of the device under test at the scanning height plane, the second parameter information used to characterize the electromagnetic field information of the calibration device at the scanning height plane, and the electromagnetic field information of the calibration device at the target height plane are obtained, namely The electromagnetic field information of the target height plane of the device under test can be determined by analogy.

As shown in FIG. 5 , in one embodiment, step S301 is the step of obtaining the electromagnetic field information of the device under test at the target height plane according to the first parameter information, the second parameter information and the electromagnetic field information of the calibration device at the target height plane Include the following steps:

Step S3011, performing PWS domain transformation on the first parameter information to obtain the first frequency domain information, performing PWS domain transformation on the second parameter information to obtain the second frequency domain information, and comparing the electromagnetic field information of the calibration device obtained by simulation on the target height plane Perform PWS domain transformation to obtain third frequency domain information.

Step S3012 , according to the first frequency domain information, the second frequency domain information and the third frequency domain information, obtain fourth frequency domain information corresponding to the electromagnetic field information on the target height plane of the device under test.

Step S3013: Perform inverse PWS domain transformation on the fourth frequency domain information to obtain electromagnetic field information on the target height plane of the device under test.

Specifically, the first parameter information, the second parameter information and the electromagnetic field information of the calibration device obtained by simulation on the target height plane can be transformed into the PWS domain according to the plane wave spectrum theory, that is, the position domain is transformed into the corresponding frequency domain information, respectively. are the first frequency domain information, the second frequency domain information and the third frequency domain information. Then, the first frequency domain information is transformed into fourth frequency domain information through the frequency domain analogy of the calibration piece, and the fourth frequency domain information corresponds to the electromagnetic field information of the target height plane of the device under test. Finally, the fourth frequency domain information is inversely transformed in the PWS domain to obtain the electromagnetic field information of the device under test at the target height plane.

In one embodiment, step S3012 is the step of obtaining fourth frequency domain information corresponding to the electromagnetic field information of the target height plane of the device under test according to the first frequency domain information, the second frequency domain information and the third frequency domain information Include the following steps:

The fourth frequency domain information corresponding to the electromagnetic field information of the target height plane of the device under test is obtained by the following formula:

为所述待测器件目标高度z_j平面的电磁场信息所对应的第四频域信息，

为仿真获得的校准器件在目标高度z_j平面的电磁场信息所对应的第三频域信息，

为所述校准器件扫描高度z_i平面的电磁场信息所对应的第二频域信息，

为所述待测器件扫描高度z_i平面的电磁场信息所对应的第一频域信息。in,

is the fourth frequency domain information corresponding to the electromagnetic field information of the target height z _j plane of the device under test,

is the third frequency domain information corresponding to the electromagnetic field information of the calibration device at the target height z _j plane obtained by simulation,

the second frequency domain information corresponding to the electromagnetic field information of the scanning height _zi plane for the calibration device,

First frequency domain information corresponding to the electromagnetic field information of the scanning height _zi plane for the device under test.

As shown in FIG. 6, in one embodiment, the electromagnetic field information includes magnetic field strength information;

Step S400, that is, according to the electromagnetic field information of the target height plane of the device to be tested, the step of determining the electrical distribution on the surface of the device to be tested includes the following steps:

Step S401 , according to the magnetic field intensity information of the target height plane of the device under test, obtain the current components in the X-axis direction and the Y-axis direction of the surface of the device under test.

Specifically, the magnetic field intensity information of the target height plane of the device under test can be first transformed into the plane wave spectrum domain, and then the current components in the X-axis direction and the Y-axis direction can be obtained by calculation.

Step S402: Determine the positional distribution of the surface current density on the surface of the device to be tested according to the current components in the X-axis direction and the Y-axis direction of the surface of the device to be tested.

Specifically, the obtained current components in the X-axis direction and the Y-axis direction are respectively inversely transformed to obtain the corresponding position domain information, and then according to the position domain information of the current component in the X-axis direction and the position domain of the current component in the Y-axis direction. The information calculation obtains the positional distribution of the surface current density on the surface of the device under test.

In one of the embodiments, the electromagnetic field information includes electric field strength information;

Step S400, that is, according to the electromagnetic field information of the target height plane of the device to be tested, the step of determining the electrical distribution on the surface of the device to be tested includes the following steps:

Step S403: Determine the surface charge distribution on the surface of the device to be tested according to the electric field intensity information of the target height plane of the device to be tested.

Specifically, the electric field intensity information of the target height plane of the device under test can be transformed into the plane wave spectral domain, and then the surface charge on the surface of the device under test can be calculated and obtained according to the plane wave spectral domain information corresponding to the electric field intensity information of the target height plane of the device under test. The distributed plane wave spectral domain information, and finally the inverse transform of the plane wave spectral domain information of the surface charge distribution on the surface of the device under test, to obtain the required surface charge distribution on the surface of the device under test.

As shown in FIG. 7 , in one embodiment, step S500, that is, the step of determining the failure position of the device under test according to the electrical distribution on the surface of the device under test includes the following steps:

Step S501 , determining the trajectory of the current signal injected into the device under test according to the positional distribution of the surface current density on the surface of the device under test.

Step S502: Determine the standing wave current distribution curve according to the trajectory of the current signal.

Step S503 , fitting the standing wave current distribution curve to determine the position of the open-circuit failure of the device under test.

When the internal circuit of the device under test is open, the current distribution along the trajectory of the current signal is in the form of a sine standing wave. After the standing wave current distribution curve is determined, the standing wave current distribution curve can be fitted according to the fitting formula. Then determine the position of the open circuit point of the device under test.

In one embodiment, step S500, that is, the step of determining the failure position of the device under test according to the electrical distribution on the surface of the device under test further includes the following steps:

Step S504 , determining the trajectory of the current signal injected into the device under test according to the surface charge distribution on the surface of the device under test.

Step S505: Determine the standing wave current distribution curve according to the trajectory of the current signal.

Step S506 , fitting the standing wave current distribution curve to determine the short-circuit failure position of the device under test.

When the surface charge distribution on the surface of the device under test is obtained, it can determine the position of the short circuit failure of the device under test, and the method is similar to the method for determining the open circuit failure position of the device under test.

In one of the embodiments, the step of fitting the standing wave current distribution curve in the above steps S503 and S506 includes the following steps:

The standing wave current distribution curve is fitted by the following fitting formula:

Among them, I is the current signal, z is the distance of the current signal from the failure position, β is the phase constant, Z ₀ is the characteristic impedance, and P _RF is the incident power.

In one embodiment, step S300, after the step of determining the electromagnetic field information of the target height plane of the device under test according to the first parameter information and the calibration data, further includes the following steps:

Step S600 , comparing the electromagnetic field distribution diagram of the target height plane of the device under test with the electromagnetic field distribution diagram of the target height plane of the good device, and determining the failure position of the device under test.

In addition to the open-circuit failure locating method in steps S501-S503 and the short-circuit failure locating method in steps S504-S506, the failure position can also be directly judged by comparing the electromagnetic field distribution maps. Specifically, the electromagnetic field distribution map of the good device on the target height plane can be obtained first, then it can be compared with the electromagnetic field distribution map of the target height plane of the device under test, and the difference position points of the electromagnetic field distribution map can be recorded. possible failure locations. This method can judge the failure position of current leakage and virtual short and continuous interruption.

The following describes the device failure location analysis method provided by this application with a specific example:

First, calibrate the near-field probe, and use the microstrip line as the calibration part used for calibration.

其中，sim表示仿真结果，ref表示校准件，x、y表示微带线表面所在的平面，γ表示电磁场信息，可以为磁场强度Hx、Hy和Hz，也可以为电场强度Ex、Ey和Ez。Specifically, the electromagnetic field information of the microstrip line at the target height z _j plane is obtained through HFSS simulation

Among them, sim represents the simulation result, ref represents the calibration part, x and y represent the plane on which the surface of the microstrip line is located, and γ represents the electromagnetic field information, which can be the magnetic field strengths Hx, Hy, and Hz, or the electric field strengths Ex, Ey, and Ez.

其中，meas表示测量结果。The microstrip line is scanned in the near field by the near-field probe, and the parameter information (that is, the first parameter information used to characterize the electromagnetic field information of the scanning height plane of the microstrip line) is read by the network analyzer, which is recorded as

Among them, meas represents the measurement result.

和

进行PWS域变换，得到对应的频域信息，即第三频域信息

和第二频域信息

According to the plane-wave spectrum theory,

and

Perform PWS domain transformation to obtain the corresponding frequency domain information, that is, the third frequency domain information

and the second frequency domain information

The following is the transformation formula of the magnetic field strength Hx as an example:

Second, near-field scanning and data preprocessing of the device under test

The device under test is scanned in the near field, and the parameter information used to characterize the electromagnetic field information of the device under test scanning height _zi plane is recorded by the network analyzer, that is, the first parameter information, which is recorded by the network analyzer as

进行PWS域变换，得到

即第一频域信息，下述为变换公式：right

Perform PWS domain transformation to get

That is, the first frequency domain information, the following is the transformation formula:

第二频域信息

以及第三频域信息

通过类比法得到第四频域信息

第四频域信息用于表征待测器件目标高度平面的电磁场信息。下面为第四频域信息的计算公式：According to the first frequency domain information

second frequency domain information

and the third frequency domain information

Obtain the fourth frequency domain information by analogy

The fourth frequency domain information is used to characterize the electromagnetic field information of the target height plane of the device under test. The following is the calculation formula of the fourth frequency domain information:

Inversely transform the fourth frequency domain information to obtain the electromagnetic field information of the target height z _j plane of the device under test:

若为Y轴或Z轴方向的磁场强度，记为

或

同样地，若测试结果是电场强度，则可记为

及

It should be noted that the electromagnetic field information is divided into electric field strength and magnetic field strength. If the test result is the magnetic field strength in the horizontal X-axis direction, it is recorded as

If it is the magnetic field strength in the Y-axis or Z-axis direction, it is recorded as

or

Similarly, if the test result is the electric field strength, it can be recorded as

and

Third, the reduction from the magnetic near field to the surface current density

进行二维傅里叶变换，得到平面波谱域信息

For the magnetic field strength information obtained above

Perform two-dimensional Fourier transform to obtain plane-wave spectral domain information

和

进行二维傅里叶变换，得到对应的平面波谱域信息。in the same way to

and

Perform a two-dimensional Fourier transform to obtain the corresponding plane wave spectral domain information.

和Y轴方向的电流分量

Calculate and obtain the current component in the X-axis direction of the device under test according to the obtained plane wave spectral domain information

and the current component in the Y-axis direction

Specifically, the current component can be calculated according to the following equation:

The calculated current component in the X-axis direction is:

The calculated current component in the Y-axis direction is:

和

并对其做平方和运算和开方运算，得到面电流密度的位置分布J^DUT(x,y)。The current component in the X-axis direction and the current component in the Y-axis direction of the device under test obtained above are inversely transformed to obtain

and

And do the square sum operation and the square root operation to get the position distribution J ^DUT (x, y) of the surface current density.

Fourth, the reduction of electric near field to surface charge

进行二维傅里叶变换，得到平面波谱域信息

For the electric field strength information obtained above

Perform two-dimensional Fourier transform to obtain plane-wave spectral domain information

Calculate the plane-wave spectral domain expression for the surface charge distribution on the DUT surface:

Finally, it is inversely transformed to obtain the surface charge distribution on the surface of the device under test:

Fifth, the failure positioning method

As shown in Fig. 8, according to the position distribution of the surface current density on the surface of the device under test obtained above, find the trajectory of the injected current signal, and draw the intensity distribution curve of the current density along the trajectory line, that is, the standing wave current distribution curve.

The following fitting formula is used to fit the standing wave current distribution curve, and calculate the possible fracture position in the vertical direction, that is, the position of the open-circuit failure of the device under test:

Among them, I represents the signal along the line, z represents the distance of the signal from the open point, Z ₀ represents the characteristic impedance, β represents the phase constant, and P _RF represents the incident power.

Similarly, through the surface charge distribution on the surface of the device under test obtained above, the position of the short-circuit failure of the device under test can be obtained in the same way.

In addition, by comparing the electromagnetic field distribution diagrams of the good device and the device under test, it is also possible to determine the position where the device under test may fail. This method can be applied to failure types such as current leakage, virtual short and virtual short. Fig. 9 shows the electromagnetic field distribution diagram of the good device and the device under test in a specific example, and Fig. 10 shows the electromagnetic field distribution diagram of the good device and the device under test in another specific example. It can be seen from the figure, There is a big difference between the electromagnetic field distribution at the failure position of the device under test and the electromagnetic field distribution at the same position of the good device, so that the failure position of the device under test can be determined.

The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity, all possible combinations of the technical features in the above-described embodiments are not described. However, as long as there is no contradiction between the combinations of these technical features, All should be regarded as the scope described in this specification.

The above-mentioned embodiments only represent several embodiments of the present invention, and the descriptions thereof are specific and detailed, but should not be construed as a limitation on the scope of the invention patent. It should be pointed out that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can also be made, which 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 appended claims.

Claims (10)

1. a device failure location analysis method, is characterized in that, described device failure location analysis method is based on near-field detection system, and described near-field detection system comprises scanning probe and signal analysis equipment, and described scanning probe is used for device to be tested Perform near-field scanning, the signal analysis device is used for injecting a signal into the device under test, and analyzing the signal generated by the scanning of the scanning probe; the device failure locating method includes: Calibrating the scanning probe to obtain calibration data; controlling the scanning probe to scan the device under test, and obtaining first parameter information, where the first parameter information is used to characterize the electromagnetic field information of the scanning height plane of the device under test; According to the first parameter information and the calibration data, determine the electromagnetic field information of the target height plane of the device under test; According to the electromagnetic field information of the target height plane of the device under test, determine the electrical distribution on the surface of the device under test; The failure position of the device under test is determined according to the electrical distribution on the surface of the device under test. 2. The device failure location analysis method according to claim 1, wherein the step of calibrating the scanning probe and acquiring calibration data comprises: The electromagnetic field information of the calibration device at the target height plane is obtained by simulation; controlling the scanning probe to scan the calibration device to obtain second parameter information, where the second parameter information is used to characterize the electromagnetic field information of the calibration device in the scanning height plane; The step of determining the electromagnetic field information of the target height plane of the device under test according to the first parameter information and the calibration data includes: According to the first parameter information, the second parameter information, and the electromagnetic field information of the calibration device at the target height plane, the electromagnetic field information of the device under test at the target height plane is obtained. 3 . The device failure location analysis method according to claim 2 , wherein, according to the first parameter information, the second parameter information and the electromagnetic field information of the calibration device in the target height plane, the obtained 3. The step of describing the electromagnetic field information of the target height plane of the device under test includes: Perform PWS domain transformation on the first parameter information to obtain first frequency domain information, perform PWS domain transformation on the second parameter information to obtain second frequency domain information, and perform simulation on the electromagnetic field of the calibration device at the target height plane. The information is transformed in the PWS domain to obtain the third frequency domain information; According to the first frequency domain information, the second frequency domain information and the third frequency domain information, obtain fourth frequency domain information corresponding to the electromagnetic field information of the target height plane of the device under test; Perform inverse PWS domain transformation on the fourth frequency domain information to obtain electromagnetic field information on the target height plane of the device under test. 4 . The device failure location analysis method according to claim 3 , wherein, according to the first frequency domain information, the second frequency domain information and the third frequency domain information, the to-be-to-be-domain information is obtained. 5 . The step of measuring the fourth frequency domain information corresponding to the electromagnetic field information of the target height plane of the device includes: The fourth frequency domain information corresponding to the electromagnetic field information of the target height plane of the device under test is obtained by the following formula:

in,

is the fourth frequency domain information corresponding to the electromagnetic field information of the target height z _j plane of the device under test,

is the third frequency domain information corresponding to the electromagnetic field information of the calibration device at the target height z _j plane obtained by simulation,

the second frequency domain information corresponding to the electromagnetic field information of the scanning height _zi plane for the calibration device,

First frequency domain information corresponding to the electromagnetic field information of the scanning height _zi plane for the device under test. 5. The device failure location analysis method according to claim 3, wherein the electromagnetic field information comprises magnetic field strength information; The step of determining the electrical distribution on the surface of the device under test according to the electromagnetic field information of the target height plane of the device under test includes: According to the magnetic field intensity information of the target height plane of the device under test, the current components in the X-axis direction and the Y-axis direction of the surface of the device under test are obtained; The positional distribution of the surface current density on the surface of the device to be tested is determined according to the current components in the X-axis direction and the Y-axis direction of the surface of the device to be tested. 6. The device failure location analysis method according to claim 3, wherein the electromagnetic field information comprises electric field strength information; The step of determining the electrical distribution on the surface of the device under test according to the electromagnetic field information of the target height plane of the device under test includes: According to the electric field intensity information of the target height plane of the device under test, the surface charge distribution on the surface of the device under test is determined. 7. The device failure location analysis method according to claim 5, wherein the step of determining the failure location of the device under test according to the electrical distribution on the surface of the device under test comprises: Determine the trajectory of the current signal injected into the device under test according to the positional distribution of the surface current density on the surface of the device under test; According to the trajectory of the current signal, determine the standing wave current distribution curve; The standing wave current distribution curve is fitted to determine the position of the open-circuit failure of the device under test. 8. The device failure location analysis method according to claim 6, wherein the step of determining the failure location of the device under test according to the electrical distribution on the surface of the device under test further comprises: According to the surface charge distribution on the surface of the device under test, determine the trajectory of the current signal injected into the device under test; According to the trajectory of the current signal, determine the standing wave current distribution curve; The standing wave current distribution curve is fitted to determine the short-circuit failure position of the device under test. 9. The device failure location analysis method according to claim 7 or 8, wherein the step of fitting the standing wave current distribution curve comprises: The standing wave current distribution curve is fitted by the following fitting formula:

Among them, I is the current signal, z is the distance of the current signal from the failure position, β is the phase constant, Z ₀ is the characteristic impedance, and P _RF is the incident power. 10 . The device failure location analysis method according to claim 1 , wherein after the step of determining the electromagnetic field information of the target height plane of the device under test according to the first parameter information and the calibration data. 11 . , the device failure location analysis method further includes: The failure position of the device under test is determined by comparing the electromagnetic field distribution diagram of the target height plane of the device under test with the electromagnetic field distribution diagram of the target height plane of the good device.

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