Method and system for testing discharge sensitivity characteristic of electronic device

Abstract

The invention relates to a method and a system for testing the discharge sensitivity characteristic of an electronic device. The method comprises the following steps: S1, dividing a plurality of same device samples in the same batch into a control group sample and a plurality of test group samples; s2, performing a control group electrical characteristic test on the control group sample to obtain characteristic reference data; s3, performing device discharge sensitive characteristic test on the test group samples by adopting a dichotomy to obtain failure voltage and failure times of the same device sample; and S4, fitting the electrostatic discharge voltage and the discharge times according to the test result, and determining the safe electrostatic discharge voltage according to the fitting result. According to the method, the ESD failure characteristics of the electronic device under the conditions of different electrostatic'discharge voltages' and'discharge times' are evaluated through comprehensive electrical characteristic characterization, the potential failure risk under an existing evaluation method is effectively avoided, and a basis and a reference can be provided for formulating and implementing targeted measures for electrostatic protection of the electronic device.

Description

Technical Field

[0001] This invention relates to the fields of semiconductor and electrostatic technology, and in particular to a method and system for testing the discharge sensitivity characteristics of electronic devices. Background Technology

[0002] Static electricity is widespread in various scientific research and production environments. Electrostatic discharge can cause electronic devices to fail, resulting in incalculable losses. With the rapid development of microelectronics technology, the feature size of advanced electronic devices is becoming smaller and their structure is becoming more complex, and their electrostatic sensitivity is also increasing. The importance of electrostatic protection for electronic devices is self-evident.

[0003] Based on the microscopic mechanisms of electronic devices, electrostatic discharge (ESD) damage can be caused by thermal secondary breakdown, melting of the conductive metal layer, bulk breakdown, dielectric breakdown, gas arc discharge, and surface breakdown. Therefore, ESD damage to electronic devices inevitably exhibits a "cumulative effect," meaning that even if a single discharge at a certain ESD voltage does not cause device failure, multiple discharges at the same voltage may still lead to failure. In other words, the ESD failure process of electronic devices is directly related to both the ESD "discharge voltage" and the "number of discharges." The classification of ESD sensitivity for microelectronic devices in China is mainly based on Method 3015.1 "Classification of ESD Sensitivity" in GJB 548C-2021 "Test Methods and Procedures for Microelectronic Devices," which uses a test circuit equivalent to a human body model (HBM) (the circuit waveform needs to be verified according to standard requirements) and is conducted at room temperature.

[0004] Currently, methods for determining electrostatic discharge (ESD) sensitivity only consider the ESD voltage factor, failing to define or mention the impact of the number of ESD discharges on the device's ESD sensitivity. However, in practical applications of electronic devices, cases have shown that even after classifying electronic devices according to current standards and implementing strict ESD protection measures based on those sensitivity levels, multiple incidents of ESD damage to electronic devices have still occurred. Analysis of the causes suggests that traditional ESD sensitivity classification methods do not take the number of ESD discharges into account. For example, an electronic device with a single discharge ESD sensitivity of HBM 100V may still be damaged if subjected to 20 discharges of 90V each. This indicates that not only will ESD voltage reaching a certain threshold cause direct device failure, but repeated exposure to ESD voltages below the threshold can also lead to failure, further validating the "cumulative effect" of ESD. Therefore, it can be inferred that the ESD sensitivity of electronic devices characterized by current standards may lead to potential device failure and ultimately, complete device failure.

[0005] In view of this, there is an urgent need for a testing method and system for the discharge sensitivity characteristics of electronic devices that comprehensively considers both electrostatic discharge voltage and discharge cycles, in order to provide targeted and effective technical support for the accurate identification of the electrostatic sensitivity of electronic devices and the implementation of electrostatic protection work. Summary of the Invention

[0006] To address the technical problems existing in the prior art, the present invention aims to provide a method and system for testing the discharge sensitivity characteristics of electronic devices, which comprehensively considers electrostatic discharge voltage and discharge cycles, and can provide a basis and reference for formulating and implementing effective and targeted electrostatic protection measures for electronic devices.

[0007] To achieve the above-mentioned objectives, this invention provides a method for testing the discharge sensitivity characteristics of electronic devices, comprising the following steps:

[0008] Step S1: Divide several identical device samples into a control group sample and several test group samples, wherein the device samples are from the same batch;

[0009] Step S2: Perform electrical characteristic tests on the control group samples to obtain characteristic reference data;

[0010] Step S3: Using the binary search method, perform device discharge sensitivity tests on several of the test group samples to obtain the electrostatic discharge failure threshold voltage and the corresponding number of electrostatic discharge failures for the same type of device sample.

[0011] Step S4: Fit the relationship between the electrostatic discharge failure threshold voltage and the number of electrostatic discharge failures based on the test results, and determine the safe electrostatic discharge voltage based on the fitting results.

[0012] In one technical solution of the present invention, step S2 specifically includes:

[0013] Step S21: Perform a leakage current test on the control group sample to obtain the sample leakage current reference value;

[0014] Step S22: Perform IV characteristic curve testing on the control group sample to obtain the IV characteristic reference curve of the sample;

[0015] Step S23: Perform CV characteristic curve testing on the control group sample to obtain the sample CV characteristic reference curve.

[0016] In one technical solution of the present invention, step S3 specifically includes:

[0017] Step S31: Set the number of electrostatic discharges to N;

[0018] Step S32: Based on the number of electrostatic discharges N, set the discharge voltage to n V, and select a set of the test group samples;

[0019] Step S33: Perform a discharge test on the test group samples;

[0020] Step S34: Perform device electrical performance tests on the test group samples after discharge to determine whether the test group samples have failed; if they have failed, record the discharge voltage as the failure voltage value and proceed to step S35; otherwise, record the discharge voltage as the non-failure voltage value and proceed to step S36.

[0021] Step S35: Select a new set of test group samples, update the discharge voltage n to the median value of the non-failure voltage value that is closest to the current discharge voltage, and return to step S33;

[0022] Step S36: Select a new set of test group samples, update the discharge voltage n to the median value of the failure voltage value that is closest to the current discharge voltage, and return to step S33;

[0023] Step S37: When the difference between the closest non-failure voltage value and the failure voltage value is less than the precise measurement voltage difference threshold, the non-failure voltage value is taken as the electrostatic discharge threshold voltage.

[0024] Step S38: Repeat steps S33 to S37 m times to obtain m electrostatic discharge threshold voltages corresponding to the number of electrostatic discharges N. Calculate the average of the m electrostatic discharge threshold voltages to obtain the electrostatic discharge failure threshold voltage corresponding to the number of electrostatic discharges N.

[0025] Step S39: Update the electrostatic discharge count and return to step S32.

[0026] In one technical solution of the present invention, in step S33, the discharge interval in the discharge test is a predetermined discharge interval.

[0027] In one technical solution of the present invention, step S34, determining whether the device has completely failed, specifically includes:

[0028] a. Perform a leakage current test on the test group samples after discharge to obtain the leakage current of the test group samples. Calculate the leakage current change based on the leakage current reference value of the samples. If the leakage current change exceeds the threshold, the sample is considered to be in failure.

[0029] b. Perform IV characteristic curve testing on the test group samples after discharge to obtain the IV characteristic curve of the test group. Calculate the drift of the IV characteristic curve of the test group based on the IV characteristic reference curve of the sample. If the drift of the IV characteristic curve of the test group exceeds the IV characteristic curve drift threshold, the sample is considered to be failed.

[0030] c. Perform CV characteristic curve testing on the test group samples after discharge to obtain the test group CV characteristic curve. Calculate the drift of the test group CV characteristic curve based on the sample CV characteristic reference curve. If the drift of the test group CV characteristic curve exceeds the CV characteristic curve drift threshold, the sample is considered to be failed.

[0031] d. Determine whether a short circuit or open circuit occurs in the IV characteristic curve of the test group. If so, the sample is considered to be faulty.

[0032] In one technical solution of the present invention, step S4 specifically includes:

[0033] Step S41: Establish a fitting function expression reflecting the relationship between the electrostatic discharge failure threshold voltage and the number of electrostatic discharge failures, wherein the fitting function expression is expressed as follows:

[0034] y = e a+bx

[0035] Where x is the electrostatic discharge voltage, y is the number of electrostatic discharges, and a and b represent the fitting parameters of the fitting function expression; the goodness of fit R of the fitting function expression 2 Not less than 0.9;

[0036] Step S42: Set the critical electrostatic discharge number M for the device, substitute it into the fitting function expression, and obtain the electrostatic discharge voltage corresponding to the failure of M electrostatic discharges, which is used as the safe electrostatic discharge voltage.

[0037] In one technical solution of the present invention, in step S42, the value of M is 10000.

[0038] According to another aspect of the present invention, a system for testing the discharge sensitivity characteristics of electronic devices is provided for implementing the above-described method, comprising:

[0039] Probe station;

[0040] An electrostatic discharge module, whose grounding terminal is connected to the first terminal of the device sample and whose output terminal is connected to the second terminal of the device sample, is used to provide an electrostatic discharge voltage to the device sample.

[0041] An electrical parameter analyzer is used to electrically connect to the device sample and perform electrical characteristic tests on the device sample.

[0042] In one embodiment of the present invention, the electrostatic discharge module includes a storage capacitor and further includes:

[0043] A charging circuit includes a high-voltage source and a charging resistor, wherein a first terminal of the high-voltage source is connected to a first terminal of the charging resistor; and a second terminal of the high-voltage source is grounded.

[0044] A discharge circuit includes a discharge resistor and a discharge electrode connected to a first end of the discharge resistor.

[0045] A charge / discharge switching switch has a first terminal connected to the first terminal of the energy storage capacitor; a second terminal of the charge / discharge switching switch is connected to the second terminal of the charging resistor; and a third terminal of the charge / discharge switching switch is connected to the second terminal of the discharging resistor. The first terminal of the charge / discharge switching switch is used to connect to either the second terminal or the third terminal of the charge / discharge switching switch to switch between the charging circuit and the discharging circuit.

[0046] The second end of the high-voltage source and the second end of the energy storage capacitor are grounded and connected to the first end of the device sample.

[0047] The second end of the discharge electrode is connected to the second end of the device sample.

[0048] In one technical solution of the present invention, the output voltage range of the high voltage source is -10 to -8000V and +10 to +8000V.

[0049] Compared with the prior art, the present invention has the following beneficial effects:

[0050] The present invention provides a method and system for testing the discharge sensitivity characteristics of electronic devices. This method employs a dichotomy approach to test the discharge sensitivity characteristics of identical device samples from the same batch. It obtains the failure voltage and failure count of the identical device samples and performs fitting analysis. Based on the fitting results, a safe electrostatic discharge voltage is determined. This approach eliminates the influence of the single factor of "discharge voltage" and comprehensively considers both the electrostatic discharge voltage and the number of discharges in the electronic device discharge sensitivity characteristics. Therefore, it provides targeted and effective technical support for the accurate identification of the electrostatic sensitivity of electronic devices and the implementation of electrostatic protection work.

[0051] This invention establishes a testing system for the electrostatic discharge (ESD) sensitivity characteristics of electronic devices, encompassing both the ESD voltage and the number of discharge cycles. This system offers a wide ESD voltage range, covering the ESD sensitivity voltages of most current electronic devices. The number of ESD discharge cycles and the discharge interval can be set as needed. The ESD model employs a modular design, allowing for selection based on requirements. Based on this system, tests are conducted on electronic devices at different ESD voltages and discharge cycles. Through comprehensive electrical characteristic characterization, the ESD failure characteristics of electronic devices under different ESD voltage and discharge cycle conditions are evaluated. The relationship between the ESD voltage threshold and the number of discharge cycles is analyzed, and a relationship model is obtained through function curve fitting. By setting a relatively high number of discharge cycles (a specific number, denoted as M, which can be set to a number unlikely to occur in practice based on the probability of ESD in the application scenario), and substituting it into the function relationship model, the calculated voltage value is the relatively safe ESD sensitivity voltage that will not cause potential failure. Using this voltage to classify the ESD sensitivity of electronic devices provides a basis and reference for developing and implementing effective and targeted ESD protection measures for electronic devices. Attached Figure Description

[0052] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are merely some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without creative effort.

[0053] Figure 1 This schematic diagram illustrates the structure of an electronic device discharge sensitivity testing system provided in one embodiment of the present invention.

[0054] Figure 2 This is a schematic diagram illustrating a method for testing the discharge sensitivity characteristics of electronic devices according to an embodiment of the present invention.

[0055] Figure 3 This schematically illustrates a flowchart of a device discharge sensitivity test for a test group sample provided according to an embodiment of the present invention. Detailed Implementation

[0056] The description of the embodiments in this specification should be taken in conjunction with the accompanying drawings, which should form part of the complete specification. In the drawings, the shape or thickness of the embodiments may be exaggerated and may be indicated in a simplified or convenient manner. Furthermore, parts of the various structures in the drawings will be described separately; it is worth noting that elements not shown in the figures or not described in words are in a form known to those skilled in the art.

[0057] The descriptions of the embodiments herein, including any references to directions and orientations, are for ease of description only and should not be construed as limiting the scope of the invention. The following description of preferred embodiments involves combinations of features, which may exist independently or in combination; the invention is not particularly limited to the preferred embodiments. The scope of the invention is defined by the claims.

[0058] Existing electrostatic discharge (ESD) sensitivity testing equipment is typically suitable for testing packaged devices. This invention provides a method and system for testing the discharge sensitivity characteristics of electronic devices. It establishes a comprehensive testing system for ESD sensitivity characteristics of electronic devices, encompassing both ESD voltage and discharge cycles. This system offers a wide ESD voltage range, covering the ESD sensitivity voltages of the vast majority of current electronic devices. The number of ESD discharges and the discharge interval can be set as needed. The ESD model adopts a modular design and can be selected as required. Based on this system, tests are conducted on electronic devices at different ESD voltages and discharge cycles. Through comprehensive electrical characteristic characterization, the ESD failure characteristics of electronic devices under different ESD voltage and discharge cycles are evaluated. The relationship between the ESD voltage threshold and the number of discharges is analyzed, and a relationship model is obtained through function curve fitting. By setting a relatively high number of discharges (a specific number, denoted as M, which can be set to a number of discharges that are difficult to occur in practice based on the probability of electrostatic discharge in the application scenario), and substituting it into the functional relationship model, the voltage value obtained by back-calculation is the relatively safe "electrostatic sensitive voltage" that will not cause potential failure. Using this voltage to classify the electrostatic sensitivity of electronic devices can provide a basis and reference for formulating and implementing effective and targeted electrostatic protection measures for electronic devices.

[0059] like Figure 1 As shown, the electronic device discharge sensitivity testing system provided by this invention includes a probe station 1, an electrostatic discharge module 2, and an electrical parameter analyzer 3. The probe station 1 is used to hold the device sample 4. The ground terminal of the electrostatic discharge module 2 is connected to the first terminal of the device sample 4, and the output terminal of the electrostatic discharge module 2 is connected to the second terminal of the device sample 4, for providing an electrostatic discharge voltage to the device sample 4. The electrical parameter analyzer 3 is electrically connected to the device sample 4 to perform electrical characteristic testing on the device sample 4. The electrical parameter analyzer 3 can be a semiconductor parameter analyzer.

[0060] In this embodiment of the invention, the electrostatic discharge module 2 includes a storage capacitor, a charging circuit, a discharging circuit, and a charge / discharge switching switch. The charging circuit includes a high-voltage source and a charging resistor; a first terminal of the high-voltage source is connected to a first terminal of the charging resistor; a second terminal of the high-voltage source is grounded. The discharging circuit includes a discharging resistor and a discharging electrode connected to a first terminal of the discharging resistor. The first terminal of the charge / discharge switching switch is connected to a first terminal of the storage capacitor, a second terminal of the charge / discharge switching switch is connected to a second terminal of the charging resistor, and a third terminal of the charge / discharge switching switch is connected to a second terminal of the discharging resistor. The first terminal of the charge / discharge switching switch is used to connect to either the second or third terminal of the charge / discharge switching switch, thereby switching between the charging and discharging circuits. The second terminal of the high-voltage source and the second terminal of the storage capacitor are grounded and connected to a first terminal of the device sample 4. The second terminal of the discharging electrode is connected to a second terminal of the device sample.

[0061] To characterize the inherent electrostatic sensitivity of electronic devices and eliminate the influence of other factors such as leads on the true electrostatic sensitivity of electronic devices, this invention constructs an electrostatic sensitivity testing system for electronic devices, applicable to the intrinsic structure of electronic devices, measuring electrostatic discharge voltage and discharge cycles. Its basic working principle is as follows: Device wafer testing is performed via probe station 1. The grounding of electrostatic discharge module 2 is connected to one electrode probe of the device under test sample 4, and the output of electrostatic discharge module 2 is connected to the other electrode probe of the device under test sample 4. Electrostatic discharge is then performed on one end of the device under test sample 4 using electrostatic discharge module 2. A dedicated shielded cable connects the semiconductor parameter analyzer test interface to the probe station probes, and the semiconductor parameter analyzer is used to test the electrical performance of the device to determine if the device has failed.

[0062] The electrostatic discharge module 2 can be an electrostatic discharge simulator, whose electrostatic discharge voltage range should cover the electrostatic sensitive voltage (±(10~8000)V) of most current electronic devices. It can be selected for manual or automatic continuous discharge, with an automatic continuous discharge interval of not less than 1 second and a maximum continuous discharge count of not less than 100 times, which can be set as needed. The high-voltage source voltage range covers ±(10~8000)V, and to ensure power output stability, a segmented power supply method can be selected. A high-response-rate high-voltage relay switch (such as an SF6 relay switch) is used to connect and disconnect the power supply terminal, the energy storage capacitor terminal, and the discharge terminal, and a matching drive control circuit is designed. Resistors R and capacitors C can be modularly designed to form independent modules, which can be selected as needed to simulate different electrostatic discharge models.

[0063] The electronic device discharge sensitivity test system constructed in this invention can be used to test the intrinsic electrostatic sensitivity characteristics of different types of electronic devices. It has the characteristics of a wide range of electrostatic discharge voltages, which can cover the electrostatic sensitivity voltages of most current electronic devices. The number of electrostatic discharges and the discharge interval can be set as needed. The electrostatic discharge model adopts a modular design and can be selected as needed, which has good operability.

[0064] like Figure 2 As shown, the method for testing the discharge sensitivity characteristics of electronic devices provided by the present invention includes the following steps:

[0065] Step S1: Divide several identical device samples into a control group sample and several test group samples. The device samples are from the same batch.

[0066] Step S2: Perform electrical characteristic tests on the control group samples to obtain characteristic reference data;

[0067] Step S2 specifically includes:

[0068] Step S21: Perform leakage current testing on the control group samples to obtain the sample leakage current reference value;

[0069] Step S22: Perform IV characteristic curve testing on the control group samples to obtain the IV characteristic reference curve of the samples;

[0070] Step S23: Perform CV characteristic curve testing on the control group sample to obtain the CV characteristic reference curve of the sample.

[0071] Step S3: Using the binary method, the device discharge sensitivity characteristics of the test group samples are tested to obtain the electrostatic discharge failure threshold voltage and the corresponding number of electrostatic discharge failures for the same type of device samples.

[0072] In step S3, as Figure 3 As shown, it specifically includes:

[0073] Step S31: Set the number of electrostatic discharges to N;

[0074] Step S32: Based on the number of electrostatic discharges N, set the discharge voltage to n V, and select a test group of samples;

[0075] Step S33: Perform discharge tests on the test group samples;

[0076] Step S34: Perform device electrical performance tests on the test group samples after discharge to determine whether the test group samples have failed; if they have failed, record the discharge voltage as the failure voltage value and proceed to step S35; otherwise, record the discharge voltage as the non-failure voltage value and proceed to step S36.

[0077] Step S35: Select a new set of test samples, update the discharge voltage n to the median value of the non-failure voltage value that is closest to the current discharge voltage, and return to step S33.

[0078] Step S36: Select a new set of test samples, update the discharge voltage n to the median value of the failure voltage that is closest to the current discharge voltage, and return to step S33.

[0079] Step S37: When the difference between the closest non-failure voltage value and the failure voltage value is less than the precise measurement voltage difference threshold, the non-failure voltage value is taken as the electrostatic discharge threshold voltage.

[0080] If the discharge voltage of this discharge test is 546V, the closest non-failure voltage value is 531V. When the accurate voltage difference threshold is 20V, 531V is taken as the electrostatic discharge threshold voltage for this set number of discharges.

[0081] Step S38: Repeat steps S33 to S37 m times to obtain m electrostatic discharge threshold voltages corresponding to the number of electrostatic discharges N. Calculate the average of the m electrostatic discharge threshold voltages to obtain the electrostatic discharge failure threshold voltage corresponding to the number of electrostatic discharges N.

[0082] During this process, the number of times m of the device discharge sensitivity test can be set according to the actual situation. For example, if it is set to 5 times, the average of the 5 accurate discharge voltage values ​​is calculated to obtain the electrostatic discharge failure threshold of 540V.

[0083] Step S39: Update the electrostatic discharge count and return to step S32.

[0084] In step S33, the discharge interval in the discharge test is a predetermined discharge interval, such as 1s.

[0085] In step S34, it is determined whether the device has completely failed, specifically including:

[0086] a. Perform leakage current testing on the test group samples after discharge to obtain the leakage current of the test group samples. Calculate the leakage current change based on the sample leakage current baseline value. If the leakage current change exceeds the leakage current change threshold, the sample is considered to be faulty. The leakage current change threshold can be the difference between the leakage current before and after discharge, or it can be a multiple of the difference between the leakage current before and after discharge.

[0087] b. Perform IV characteristic curve testing on the test group samples after discharge to obtain the IV characteristic curve of the test group. Calculate the drift of the IV characteristic curve of the test group based on the IV characteristic reference curve of the sample. If the drift of the IV characteristic curve of the test group exceeds the IV characteristic curve drift threshold, the sample is considered to be failed.

[0088] c. Perform CV characteristic curve testing on the test group samples after discharge to obtain the CV characteristic curve of the test group. Calculate the drift of the CV characteristic curve of the test group based on the CV characteristic reference curve of the sample. If the drift of the CV characteristic curve of the test group exceeds the CV characteristic curve drift threshold, the sample is considered to be failed.

[0089] d. Determine whether a short circuit or open circuit occurs in the IV characteristic curve of the test group. If so, the sample is considered to be faulty.

[0090] Step S4: Fit the relationship between the electrostatic discharge failure threshold and the number of electrostatic discharge failures based on the test results, and determine the safe electrostatic discharge voltage based on the fitting results.

[0091] Step S4 specifically includes:

[0092] Step S41: Obtain the electrostatic discharge voltage and discharge count obtained during the device electrostatic discharge test;

[0093] Step S42: Establish a fitting function expression reflecting the relationship between the number of electrostatic discharges and the electrostatic discharge voltage. The fitting function expression is expressed as follows:

[0094] y = e a+bx

[0095] Where x is the electrostatic discharge voltage, y is the number of electrostatic discharges, and a and b represent the fitting parameters of the fitting function expression; the goodness of fit R of the fitting function expression... 2 Not less than 0.9;

[0096] Step S43: Set the critical electrostatic discharge (ESD) count M for the device, substitute it into the fitting function expression, and obtain the ESD voltage corresponding to the failure after M ESDs, which is taken as the safe ESD voltage. The value of M is set to 10000. The value of M can be set according to the probability of ESD occurring in the application scenario.

[0097] In embodiments of the present invention, electrostatic discharge testing of devices can be carried out using an electronic device discharge sensitivity testing system.

[0098] The device under test sample 4 is placed on the stage of probe station 1 and observed using the microscope unit display (CCD) of probe station 1. The probe is adjusted to ensure good contact between the probe and the pins of the device under test sample 4, and the device wafer test is carried out. An electrostatic discharge model (including the number of electrostatic discharges and the discharge voltage) is selected, and it is confirmed that the output terminal of the electrostatic discharge simulator is connected to the electrode probe of the device electrostatic test terminal. The electrostatic discharge test of the device is performed, with an interval of 1 second between every two discharges (which can be adjusted as needed). The number of discharges can be set.

[0099] To more efficiently and quickly locate the electrostatic sensitivity of the electronic device under test, a "dichotomy method" is used for testing. The specific testing procedure is as follows: Figure 3 As shown: Several samples of each device structure from the same batch were selected and divided into several groups. One group served as a control group, which was not subjected to electrostatic discharge treatment. Its capacitance-voltage and current-voltage characteristics were tested as a reference. The interval between each discharge (e.g., 1 second) and the number of discharges N were set, ranging from 1 to over 100 times, such as 1, 5, 20, 50, and 100 times (the specific number of discharges can be adjusted according to the actual test conditions, but the maximum number of discharges should not be lower than the detection threshold, which can be set according to the actual electrical characteristics of the device sample under test, such as 100 times). Tests were conducted sequentially. In specific experiments, the maximum number of discharges can be appropriately increased according to the specific test conditions to ensure the reasonableness and universality of the results.

[0100] For each given number of electrostatic discharges (ESDs) N, the "dichotomy method" test procedure is used to test the ESD failure threshold voltage. A specific ESD voltage and number of discharges are applied to the device, and then a semiconductor parameter analyzer is used to test the device's electrical performance. The device's complete failure is determined by comprehensively considering four electrical characteristics: leakage current, relative drift of the IV curve, relative drift of the CV curve, and short circuit / open circuit: 1) Leakage current: First, the leakage current of the control group (i.e., before ESD) is tested as the baseline value of the electronic device's leakage current. After the ESD test, the leakage current generated by the electronic device under the specified voltage is tested again. If the change in leakage current after the ESD test exceeds a "certain proportion" (e.g., more than 1000 times or greater than 1μA) compared to the leakage current before the ESD test (i.e., the control group), failure is considered to have occurred. 2) Relative drift of the IV curve: The IV characteristic curve is measured before the ESD test. After the ESD test, the IV characteristic curve is measured again. If the drift exceeds a "certain proportion" (e.g., more than 30%), failure is considered to have occurred. 3) Relative Drift of CV Curve: Measure the CV characteristic curve before the electrostatic discharge (ESD) test. After the ESD test, measure the CV characteristic curve again. If the drift exceeds a certain percentage (e.g., more than 30%), failure is considered to have occurred. 4) Short Circuit / Open Circuit: After the ESD test, measure the IV characteristic curve. If a short circuit or open circuit occurs, failure is considered to have occurred. It should be noted that the specific value of the "certain percentage" can be determined through a comprehensive evaluation of the four electrical characteristics based on actual test results during the actual experiment.

[0101] Based on the test results regarding device failure, continue the next step of the test according to the "dichotomy" test procedure until the electrostatic discharge (ESD) failure threshold voltage of the device is measured after a set number of discharges. Record the device type, serial number, ESD voltage at device failure, and discharge count as a set of data to obtain the ESD failure threshold voltage for that set number of ESD discharges. The data obtained for each set of discharges constitutes one set, with a minimum of 5 sets. Considering that there are still certain microscopic differences among devices from the same batch or on the same substrate, the more devices tested, the better. Each set should repeatedly test at least 5 devices, and the average failure threshold voltage should be calculated as the ESD failure threshold voltage for that set number of ESD discharges.

[0102] Since electronic devices with HBM sensitivity above 8000V are generally considered insensitive devices, the discharge voltage n starts from 8000V to complete the positive polarity electrostatic voltage test. Then, n starts from -8000V to perform the negative polarity electrostatic voltage test, thus achieving sensitivity characterization under both positive and negative polarities.

[0103] After the test is completed, function model fitting and threshold voltage determination can be performed. Data processing software (such as Orign) can be used to process the electrostatic discharge voltage and discharge count data obtained from the device electrostatic discharge test according to the formula y = e a+bx By performing a fit, an e-exponential function expression reflecting the relationship between the number of electrostatic discharges and the electrostatic discharge voltage is obtained. The goodness of fit R of the fitted function is... 2 The goodness of fit should be no less than 0.9. If the goodness of fit does not meet the requirements, additional test data should be added and the fit should be refitted.

[0104] Based on the fitted expression, a critical point is set at the number of electrostatic discharges (ESDs) a device can withstand (M is the number of discharges that are unlikely to occur in reality, such as 10,000; this value can be set according to the probability of ESDs in the application scenario). A device that withstands M ESDs without completely failing is considered to be able to fully withstand that intensity of ESD and will not experience potential failure. Substituting M into the fitted function expression, the ESD voltage corresponding to failure after M ESDs is calculated. This voltage value is the relatively safe "ESD-sensitive voltage" that will not cause potential failure. Using this as the basis for classifying the ESD sensitivity of electronic devices, the ESD sensitivity characteristics based on ESD "discharge voltage" and "discharge count" can be obtained.

[0105] The above method effectively addresses the problem that existing methods for determining the electrostatic sensitivity of electronic devices only consider the electrostatic discharge voltage, neglecting the potential risk of failure due to the "cumulative effect" of electrostatic discharge. This method considers both the electrostatic discharge voltage and the number of discharges when testing the electrostatic sensitivity of electronic devices. Based on the test results, a function model is fitted and a threshold voltage is determined. The resulting voltage value is a relatively safe "electrostatic sensitivity voltage" that is less prone to potential failure. Using this voltage to classify the electrostatic sensitivity of electronic devices provides a basis and reference for developing and implementing effective and targeted electrostatic protection measures for electronic devices.

[0106] Finally, it should be noted that the above description represents a preferred embodiment of the present invention. It should be pointed out that although preferred embodiments have been described, those skilled in the art, once they understand the basic inventive concept of the present invention, can make various improvements and modifications without departing from the principles described herein. These improvements and modifications should also be considered within the scope of protection of the present invention. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the embodiments of the present invention.

Claims

1. A method for testing the discharge sensitivity characteristics of electronic devices, characterized in that, Includes the following steps: Step S1: Divide several identical device samples into a control group sample and several test group samples, wherein the device samples are from the same batch; Step S2: Perform electrical characteristic tests on the control group samples to obtain characteristic reference data; Step S3: Using the binary search method, perform device discharge sensitivity tests on several of the test group samples to obtain the electrostatic discharge failure threshold voltage and the corresponding number of electrostatic discharge failures for the same type of device sample. Step S4: Fit the relationship between the electrostatic discharge failure threshold voltage and the number of electrostatic discharge failures based on the test results, and determine the safe electrostatic discharge voltage based on the fitting results.

2. The method for testing the discharge sensitivity characteristics of electronic devices according to claim 1, characterized in that, Step S2 specifically includes: Step S21: Perform a leakage current test on the control group sample to obtain the sample leakage current reference value; Step S22: Perform IV characteristic curve testing on the control group sample to obtain the IV characteristic reference curve of the sample; Step S23: Perform CV characteristic curve testing on the control group sample to obtain the sample CV characteristic reference curve.

3. The method for testing the discharge sensitivity characteristics of electronic devices according to claim 2, characterized in that, Step S3 specifically includes: Step S31: Set the number of electrostatic discharges to N; Step S32: Based on the number of electrostatic discharges N, set the discharge voltage to n V, and select a set of the test group samples; Step S33: Perform a discharge test on the test group samples; Step S34: Perform device electrical performance tests on the test group samples after discharge to determine whether the test group samples have failed; if they have failed, record the discharge voltage as the failure voltage value and proceed to step S35; otherwise, record the discharge voltage as the non-failure voltage value and proceed to step S36. Step S35: Select a new set of test group samples, update the discharge voltage n to the median value of the non-failure voltage value that is closest to the current discharge voltage, and return to step S33; Step S36: Select a new set of test group samples, update the discharge voltage n to the median value of the failure voltage value that is closest to the current discharge voltage, and return to step S33; Step S37: When the difference between the closest non-failure voltage value and the failure voltage value is less than the precise measurement voltage difference threshold, the non-failure voltage value is taken as the electrostatic discharge threshold voltage. Step S38: Repeat steps S33 to S37 m times to obtain m electrostatic discharge threshold voltages corresponding to the number of electrostatic discharges N. Calculate the average of the m electrostatic discharge threshold voltages to obtain the electrostatic discharge failure threshold voltage corresponding to the number of electrostatic discharges N. Step S39: Update the electrostatic discharge count and return to step S32.

4. The method for testing the discharge sensitivity characteristics of electronic devices according to claim 3, characterized in that, In step S33, the discharge interval in the discharge test is a predetermined discharge interval.

5. The method for testing the discharge sensitivity characteristics of electronic devices according to claim 3, characterized in that, In step S34, determining whether the device has completely failed specifically includes: a. Perform a leakage current test on the test group samples after discharge to obtain the leakage current of the test group samples. Calculate the leakage current change based on the leakage current reference value of the samples. If the leakage current change exceeds the threshold, the sample is considered to be in failure. b. Perform IV characteristic curve testing on the test group samples after discharge to obtain the IV characteristic curve of the test group. Calculate the drift of the IV characteristic curve of the test group based on the IV characteristic reference curve of the sample. If the drift of the IV characteristic curve of the test group exceeds the IV characteristic curve drift threshold, the sample is considered to be failed. c. Perform CV characteristic curve testing on the test group samples after discharge to obtain the test group CV characteristic curve. Calculate the drift of the test group CV characteristic curve based on the sample CV characteristic reference curve. If the drift of the test group CV characteristic curve exceeds the CV characteristic curve drift threshold, the sample is considered to be failed. d. Determine whether a short circuit or open circuit occurs in the IV characteristic curve of the test group. If so, the sample is considered to be faulty.

6. The method for testing the discharge sensitivity characteristics of electronic devices according to claim 5, characterized in that, Step S4 specifically includes: Step S41: Establish a fitting function expression reflecting the relationship between the electrostatic discharge failure threshold voltage and the number of electrostatic discharge failures, wherein the fitting function expression is expressed as follows: y; a+bx Where x is the electrostatic discharge voltage, y is the number of electrostatic discharges, and a and b represent the fitting parameters of the fitting function expression; the goodness of fit R of the fitting function expression 2 Not less than 0.9; Step S42: Set the critical electrostatic discharge number M for the device, substitute it into the fitting function expression, and obtain the electrostatic discharge voltage corresponding to the failure of M electrostatic discharges, which is used as the safe electrostatic discharge voltage.

7. The method for testing the discharge sensitivity characteristics of electronic devices according to claim 6, characterized in that, In step S42, the value of M is 10000.

8. A system for testing the discharge sensitivity characteristics of electronic devices, characterized in that, For implementing the method as described in any one of claims 1 to 7, comprising: Probe station; An electrostatic discharge module, whose grounding terminal is connected to the first terminal of the device sample and whose output terminal is connected to the second terminal of the device sample, is used to provide an electrostatic discharge voltage to the device sample. An electrical parameter analyzer is used to electrically connect to the device sample and perform electrical characteristic tests on the device sample.

9. The electronic device discharge sensitivity test system according to claim 8, characterized in that, The electrostatic discharge module includes a storage capacitor and also includes: A charging circuit includes a high-voltage source and a charging resistor, wherein a first terminal of the high-voltage source is connected to a first terminal of the charging resistor; and a second terminal of the high-voltage source is grounded. A discharge circuit includes a discharge resistor and a discharge electrode connected to a first end of the discharge resistor. A charge / discharge switching switch has a first terminal connected to the first terminal of the energy storage capacitor; a second terminal of the charge / discharge switching switch is connected to the second terminal of the charging resistor; and a third terminal of the charge / discharge switching switch is connected to the second terminal of the discharging resistor. The first terminal of the charge / discharge switching switch is used to connect to either the second terminal or the third terminal of the charge / discharge switching switch to switch between the charging circuit and the discharging circuit. The second end of the high-voltage source and the second end of the energy storage capacitor are grounded and connected to the first end of the device sample. The second end of the discharge electrode is connected to the second end of the device sample.

10. The electronic device discharge sensitivity test system according to claim 9, characterized in that, The output voltage range of the high-voltage source is -10 to -8000V and +10 to +8000V.

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