Field emission volt-ampere characteristic testing method and device

Abstract

The invention belongs to the technical field of electrical device testing, and discloses a field emission volt-ampere characteristic testing method and device, and the method comprises the steps: an initial step: initializing a volt-ampere testing curve, and taking the minimum value of a voltage scanning range as a current voltage value; a testing step: inputting the current voltage value into the field emission device to obtain a detection current value; updating a volt-ampere test curve according to the current voltage value and the detection current value; judging whether the detection current value is greater than a preset current test threshold value or not; if not, adding the current voltage value and the current stepping voltage to obtain an updated current voltage value; judging whether the updated current voltage value exceeds a voltage scanning range or not; if yes, updating the voltage scanning range according to a preset expansion proportion, and returning to the initial step; and if not, returning to the testing step. According to the invention, by dynamically adjusting the voltage scanning range and the stepping voltage, both the testing efficiency and the testing precision are considered.

Description

Technical Field

[0001] This application relates to the field of electrical device testing technology, and in particular to a method and apparatus for testing field emission current-voltage characteristics. Background Technology

[0002] In existing literature on the current-voltage (IV) characteristic testing of field emission devices, the core idea is mostly to achieve voltage scanning and current acquisition by controlling hardware such as power supply and ammeter, and then storing and displaying the results.

[0003] However, while currently available volt-ampere characteristic testing methods can achieve automated testing and data acquisition to a certain extent, they still have the following shortcomings: 1. Existing technologies generally use a preset fixed voltage scanning range. However, since the generation threshold of field emission current is closely related to various conditions, it is very easy for the fixed voltage scanning range to result in a voltage far exceeding the required voltage when testing sample A, but failing to trigger field emission of sample B, or even causing overload or damage to the emission source when testing sample A; 2. Existing technologies generally use fixed voltage step values ​​for scanning, which can easily lead to low sampling efficiency in the low voltage region and data loss and risks in the high voltage region; 3. Most existing volt-ampere characteristic testing methods and systems are limited to the acquisition and display of voltage-current relationships. The test results usually remain at the level of the original IV curve and do not integrate a dedicated data processing method for field emission characteristics. Summary of the Invention

[0004] This application provides a method and apparatus for testing field emission current-voltage characteristics, which can avoid sample damage caused by field emission devices being subjected to high voltage for a long time. By dynamically adjusting the step voltage, it balances testing efficiency and accuracy.

[0005] In a first aspect, embodiments of this application provide a method for testing field emission current-voltage characteristics, including: The voltage scan range and current step voltage are determined based on user input parameters or preset default parameters. The initial step is to initialize the voltage-current test curve and use the minimum value of the voltage scan range as the current voltage value. The testing procedure involves inputting the current voltage value into the field emission device to obtain the detection current value. Update the volt-ampere test curve based on the current voltage and current values; Determine whether the detected current value is greater than the preset current test threshold; If so, perform FN transformation and linear fitting on the volt-ampere test curve to obtain the test result report; If not, add the current voltage value and the current step voltage to obtain the updated current voltage value; Calculate the rate of change of current based on the volt-ampere test curve; update the current step voltage based on the rate of change of current. Determine whether the updated current voltage value exceeds the voltage scan range; if yes, update the voltage scan range according to the preset expansion ratio and return to the initial step; if no, return to the test step.

[0006] Furthermore, the voltage scan range and current step voltage are determined based on user-input parameters or preset default parameters, including: Determine if user input parameters exist; if so, determine if the user input parameters meet the preset test standards. If yes, the voltage scan range and current step voltage are determined based on the user input parameters; if no user input parameters are available, the voltage scan range and current step voltage are determined based on the preset default parameters.

[0007] Furthermore, the method also includes: After performing the test steps, determine whether the detected current value exceeds the current safety threshold; If yes, then power off the field emission device; if not, update the current-voltage test curve.

[0008] Furthermore, the method also includes: If the detected current value is greater than the preset current test threshold, the volt-ampere test curve corresponding to the previous voltage scan range is obtained and used as the historical test curve; the convergence value of the volt-ampere test curve is determined based on the historical test curve. If the convergence value is greater than or equal to the preset convergence threshold, then the volt-ampere test curve is subjected to FN transformation and linear fitting.

[0009] Furthermore, the method also includes: If the convergence value is less than the preset convergence threshold, then determine whether the number of volt-ampere test curves has reached the preset loop threshold. If yes, then generate and display the unstable test result information; if no, then adjust the time interval of the current voltage value input to the field emission device according to the preset delay ratio, and return to the initial step.

[0010] Furthermore, the above-mentioned FN transform and linear fitting of the volt-ampere test curve yields a test result report, including: The FN curve is obtained by performing an FN transformation on the volt-ampere test curve; Perform linear fitting on one or more segments of the FN curve to obtain fitting parameters and outlier information; A test result report is generated based on the volt-ampere test curve, FN curve, fitting parameters, and outlier information.

[0011] Furthermore, updating the current step voltage based on the rate of change of current includes: Obtain the first change threshold, the second change threshold, and the step voltage adjustment ratio; if the current change rate is less than or equal to the first change threshold, increase the current step voltage according to the step voltage adjustment ratio; if the current change rate is greater than the first change threshold and less than or equal to the second change threshold, keep the current step voltage unchanged; if the current change rate is greater than the second change threshold, increase or decrease the current step voltage according to the step voltage adjustment ratio.

[0012] Secondly, embodiments of this application provide a field emission current-voltage characteristic testing device, comprising: The determination module is used to determine the voltage scan range and the current step voltage based on user input parameters or preset default parameters; The initialization module is used to initialize the voltage-current test curve, taking the minimum value of the voltage scan range as the current voltage value; The test module is used to input the current voltage value into the field emission device to obtain the detection current value; The plotting module is used to update the volt-ampere test curve based on the current voltage and current values. The output judgment module is used to determine whether the detected current value is greater than the preset current test threshold. The data processing module is used to perform FN transformation and linear fitting on the volt-ampere test curve when the detected current value is greater than the preset current test threshold, and to obtain the test result report. The adaptive module is used to add the current voltage value and the current step voltage to obtain the updated current voltage value when the detected current value is less than or equal to the preset current test threshold; calculate the current change rate according to the volt-ampere test curve; and update the current step voltage according to the current change rate. The loop module is used to determine whether the updated current voltage value exceeds the voltage scanning range; if so, the voltage scanning range is updated according to the preset expansion ratio and the module returns to the initial module; otherwise, the module returns to the test module.

[0013] Thirdly, embodiments of this application provide a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it performs the steps of the field emission current-voltage characteristic test method as described in any of the above embodiments.

[0014] Fourthly, embodiments of this application provide a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the field emission current-voltage characteristic testing method as described in any of the above embodiments.

[0015] In summary, compared with the prior art, the beneficial effects of the technical solution provided in this application include at least the following: This application provides a field emission current-voltage characteristic testing method. First, during the current-voltage test scanning process, it determines whether the current value detected has reached the preset current test threshold during field emission, i.e., the current threshold at which the field emission device enters the emission state. If so, the test can be terminated and the measured current-voltage test curve can be output. If not, and the upper limit of the voltage scan range has been reached, and the current voltage value cannot be increased further according to the current step voltage, it indicates that the current voltage scan range is too small, and the voltage scan range needs to be further expanded and the test repeated. This application can terminate the test in time when the field emission device enters the emission state by adaptively adjusting the voltage scan range gradually. Second, this application judges whether the current step voltage is reasonable based on the current change rate of the current-voltage test curve, and adjusts the current step voltage accordingly. This not only shortens the test time but also reduces the risk of breakdown caused by sudden current increases. Finally, this application adds data processing operations such as FN transformation and linear fitting based on the current-voltage test curve, making the test result report more comprehensive and accurate. Attached Figure Description

[0016] Figure 1 A flowchart of a field emission current-voltage characteristic testing method provided for an exemplary embodiment of this application.

[0017] Figure 2 This is a schematic diagram of a user input parameter setting interface provided for an exemplary embodiment of this application.

[0018] Figure 3 This is a schematic diagram showing the volt-ampere test curves of a multi-round test provided for an exemplary embodiment of this application.

[0019] Figure 4 This is a schematic diagram of the FN conversion result of the volt-ampere test curve provided as an exemplary embodiment of this application.

[0020] Figure 5 This is a structural diagram of a field emission current-voltage characteristic testing device provided as an exemplary embodiment of this application. Detailed Implementation

[0021] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0022] Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0023] Automated field emission testing systems typically comprise two main functional modules: an "I-V characteristic testing" module and a "data processing" module. For the "data processing" module, there are few published documents outlining integrated solutions for data quality control and processing throughout the entire field emission testing process. Regarding I-V characteristic testing (IV), several similar technical solutions exist. Their core idea is mostly to control hardware such as power supplies and ammeters to achieve voltage scanning and current acquisition, and then store and display the results. Typical related patents include: Patent CN102944786A, "A Method for Measuring the I-V Characteristics of Electrical Materials," which is based on the LabVIEW platform and utilizes testing equipment such as a constant voltage source and a picoammeter to build an I-V characteristic testing system. This method can measure the I-V characteristics of electrical materials under constant voltage conditions and display and store the results in real time. Patent CN118244078A, "A Method for Testing the I-V Characteristics of Devices Based on LabVIEW and Neural Networks," proposes a testing method combining LabVIEW and neural network algorithms. LabVIEW enables automated control of the testing hardware and provides a graphical interface for real-time display of test results. Regarding power supply, this method utilizes two digital source meters to provide voltage to the device. During testing, a preset voltage scan range and fixed voltage step values ​​are required to complete the IV curve measurement. Patent CN120233202A, "A Conductivity Performance Testing System for Diodes," proposes a conductivity performance testing system suitable for diodes. The system's power module automatically adjusts the output voltage according to preset voltage change steps and time intervals, and, in conjunction with a data acquisition module, completes conductivity characteristic testing and recording. In summary, most existing volt-ampere characteristic testing technologies rely on fixed step voltages, achieving a certain degree of automation and data visualization in the testing process.

[0024] However, while existing current-voltage characteristic testing methods and systems can achieve automated testing and data acquisition to a certain extent, they still have the following shortcomings: 1. Existing technologies use a preset fixed voltage scan range. Throughout the test, the voltage gradually increases according to the set start and end voltages until it reaches the preset end voltage. This approach has two prominent problems in field emission testing: First, the voltage scan range setting lacks flexibility. The generation threshold of the field emission current is closely related to various conditions, such as: the distance between the anode and cathode of the sample under test (i.e., the field emission device under test), the air pressure level in the vacuum chamber, and the geometry of the emitter surface. Under different conditions, the emission threshold of the sample varies greatly. For example, when the anode-cathode distance of sample A is only 50 nm, its emission threshold voltage may be lower than 1 V; while the anode-cathode distance of sample B reaches 1 μm, and the ambient air pressure is 10⁻⁻⁻⁶. 6At a voltage of Pa, the emission threshold voltage can be as high as 2500V. If a uniform voltage scan range of 1V is set, it obviously cannot trigger field emission of sample B; while setting it to a voltage scan range of 2500V would result in a voltage far exceeding the required value when testing sample A. This means that testers need to repeatedly modify the voltage scan range and re-perform the experiment, a cumbersome process that contradicts the goal of "automated testing." Secondly, the termination voltage cannot be adaptively adjusted. In existing technology, even if the sample has reached the emission state at a lower voltage, the system will continue to increase the voltage according to a preset step until the termination voltage of the scan range. For samples with low threshold voltages (such as sample A above), when the voltage continuously rises to near the preset high termination value (such as 2500V), it can easily lead to overload or even damage to the emission source. This method, which cannot dynamically adjust the termination voltage according to the actual emission characteristics of the sample, not only poses a risk of sample burnout but also results in unnecessary waste of time and energy. 2. Existing technologies generally employ fixed voltage step values ​​for scanning, meaning that within a preset voltage scanning range, the voltage increment remains constant (e.g., 0.1V, 0.5V, or 1V). However, sampling efficiency is low in the low-voltage region. The field emission current and the applied electric field exhibit an approximately exponential relationship. In the low-voltage region, current changes slowly, and using a small fixed step for data acquisition leads to overly dense test points, which often lack practical significance, only increasing testing time and data processing volume, thus reducing overall efficiency. Secondly, the high-voltage region presents data gaps and risks. As the voltage increases, the field emission current increases exponentially. Continuing to use the same fixed step may result in excessively large current differences between adjacent data points, failing to capture the details of rapid current changes. This not only leads to insufficient test data in the high-current region, affecting the linear fitting accuracy of the Fowler–Nordheim (FN) curve, but also easily causes instantaneous current overload, increasing the risk of sample breakdown or burnout. Finally, the current variation patterns of different field emission devices vary significantly across different voltage ranges, and a fixed step cannot automatically adjust according to the real-time current growth trend. This means that the system struggles to balance test accuracy and sample safety throughout the entire testing process. 3. Existing voltage-current characteristic testing methods are mostly limited to acquiring and displaying the voltage-current relationship, with test results typically remaining at the level of the raw IV curve. While these data can reflect the general trend of field emission current changing with voltage, existing technologies do not integrate a dedicated data processing module for field emission characteristics. The field emission mechanism usually requires FN conversion of IV data to obtain the FN curve and further extract key parameters such as the effective work function and field enhancement factor of the emission source. However, existing patented testing methods only provide data storage or simple curve display, without including automated FN conversion and fitting functions. To address the above problems, a field emission device testing method capable of adaptive voltage scanning + adaptive voltage stepping + FN data analysis is provided. Please refer to [link to relevant documentation]. Figure 1 This application provides a method for testing field emission current-voltage characteristics, including: Step S1: Determine the voltage scanning range and the current step voltage based on user input parameters or preset default parameters.

[0025] Specifically, it determines whether user input parameters exist; if so, it determines whether the user input parameters meet the preset test standards; if so, it determines the voltage scan range and the current step voltage based on the user input parameters; if not, or if no user input parameters exist, it determines the voltage scan range and the current step voltage based on the preset default parameters.

[0026] Among them, the voltage scan range and the current step voltage are parameters that are user input parameters or preset default parameters, including the preset current test threshold in the following steps, which are also parameters that are user input parameters or preset default parameters.

[0027] like Figure 2 As shown, the user input parameters are the parameter settings interface that the execution system of this application prompts the user on the computer's display interface when it starts up. The system determines whether to enable the preset default parameters by detecting whether the user manually inputs test parameters.

[0028] The preset test standards include whether the starting voltage of the voltage scan range is less than the ending voltage, whether the current step voltage is within the allowable range, and whether the preset current test threshold exceeds the actual value of the field emission device entering the emission state. If the user input parameters do not meet the preset test standards, the user can be prompted with the reason for the unreasonableness. If the user does not make any changes, the preset default parameters will be used.

[0029] Step S2, initialization step: initialize the voltage-current test curve and take the minimum value of the voltage scan range as the current voltage value.

[0030] Step S3, the testing step, inputs the current voltage value into the field emission device to obtain the detection current value.

[0031] Furthermore, after each input of the current voltage value, i.e., after executing the test step, it is determined whether the detected current value exceeds the current safety threshold; if so, the field emission device is powered off to protect the field emission device and the source meter; if not, the volt-ampere test curve is updated based on the current voltage value and the detected current value.

[0032] It is worth noting that the aforementioned current safety threshold is set during initialization. Once the execution system and the source meter (such as the TH2695 model) establish a communication connection, the corresponding current safety threshold is automatically loaded based on the source meter's device model. For example, when connecting the TH2695 source meter, the current safety threshold is set to 2 mA. This means that in addition to the parameters of the field emission device being tested, the safety of the source meter used to input voltage and read current values ​​must also be considered during the testing process.

[0033] Step S4: Update the volt-ampere test curve based on the current voltage value and the detected current value.

[0034] Specifically, a set voltage command is sent to the source meter based on the current voltage value, and the detected current value fed back by the source meter is read in real time. At each voltage point, the current value is synchronously written to the cache, and the volt-ampere test curve is plotted in real time on the graphical interface.

[0035] Step S5: Determine whether the detected current value is greater than the preset current test threshold.

[0036] Step S6: If yes, perform FN transformation and linear fitting on the volt-ampere test curve to obtain the test result report.

[0037] Specifically, if the detected current value is greater than the preset current test threshold, it indicates that the field emission device has entered the emission state, and the test ends. Based on the last volt-ampere test curve, FN transformation and linear fitting are performed to obtain the test result report and display.

[0038] Step S7: If not, add the current voltage value and the current step voltage to obtain the updated current voltage value.

[0039] Step S8: Calculate the rate of change of current based on the volt-ampere test curve; update the current step voltage based on the rate of change of current.

[0040] Specifically, the current change rate dI / dV is calculated using the volt-ampere test curve to determine the current change trend, and the current step voltage is adjusted accordingly. First, a first change threshold, a second change threshold, and a step voltage adjustment ratio are obtained. If the current change rate is less than or equal to the first change threshold, the current step voltage is increased according to the step voltage adjustment ratio. If the current change rate is greater than the first change threshold but less than or equal to the second change threshold, the current step voltage remains unchanged. If the current change rate is greater than the second change threshold, the current step voltage is increased or decreased according to the step voltage adjustment ratio.

[0041] For example, if the first threshold change is 5%, the second threshold change is 15%, and the step voltage adjustment ratio is 10%, then when the current change rate is less than 5%, it is considered low, indicating that the current change in the current range is slow, and the step voltage needs to be increased to speed up the scanning process; when the current change rate is between 5% and 15%, it is considered moderate, and the current step voltage remains unchanged; when the current change rate exceeds 15%, it is considered high, and the current step voltage needs to be reduced to increase the sampling point density in order to finely characterize the current change process in the threshold region. This dynamic adjustment mechanism avoids the problems of "redundant sampling" in the low voltage region and "data loss" in the high voltage region of the traditional fixed step method. Taking the current step voltage set to 0.1V as an example, if a low current change rate is detected, the current step voltage is increased by 10%, and gradually amplified in subsequent tests. By the 42nd sampling, the step voltage can be increased to approximately 5V.

[0042] Step S9: Determine whether the updated current voltage value exceeds the voltage scanning range; if yes, update the voltage scanning range according to the preset expansion ratio and return to the initial step; if no, return to the test step.

[0043] Specifically, taking a voltage scan range of 0–200V and a preset expansion ratio of 20% as an example, if the detected current value within this voltage scan range does not reach the preset current test threshold, the voltage scan range will be expanded by 20% each time. If the first round of voltage increase from 0V to 200V does not trigger the preset current test threshold, the voltage scan range for the second round will be adjusted to 0–240V, and so on, until the detected current value reaches the preset current test threshold.

[0044] like Figure 3 As shown, after returning to the initial step, due to the initialization of the volt-ampere test curve, it is equivalent to the volt-ampere test curve being redrawn in each loop, that is, a volt-ampere test curve will be drawn for each voltage scan range.

[0045] The field emission current-voltage characteristic testing method provided in the above embodiments firstly determines whether the detected current value has reached the preset current test threshold during field emission, i.e., the current threshold at which the field emission device enters the emission state, during the scanning process of the current-voltage test. If yes, the test can be ended and the measured current-voltage test curve can be output. If no, and the upper limit of the voltage scan range has been reached, and the current voltage value cannot be increased further according to the current step voltage, it indicates that the current voltage scan range is small and the voltage scan range needs to be further expanded and the test should be performed again. By adaptively adjusting the voltage scan range to gradually expand, this application can terminate the test in time when the field emission device enters the emission state. When the field emission device enters the emission state at a low voltage, the scan can be terminated in advance to avoid unnecessary time waste and sample damage caused by the continuous increase of voltage. This achieves improved versatility, adaptability, and safety under different sample and environmental conditions. Secondly, this application determines the rationality of the current step voltage based on the current change rate of the volt-ampere test curve and adjusts the current step voltage accordingly. When the current changes slowly, the step is increased to speed up the scan, and when the current rises rapidly or approaches the threshold, the step is decreased to increase the data point density. This not only shortens the test time but also reduces the risk of breakdown caused by sudden current surges. Finally, this application adds data processing operations such as FN transformation and linear fitting based on the volt-ampere test curve, making the test result report more comprehensive and accurate.

[0046] In some embodiments, the method further includes: If the detected current value is greater than the preset current test threshold, the volt-ampere test curve corresponding to the previous voltage scan range is obtained and used as the historical test curve; the convergence value of the volt-ampere test curve is determined based on the historical test curve.

[0047] If the convergence value is greater than or equal to the preset convergence threshold, then the volt-ampere test curve is subjected to FN transformation and linear fitting.

[0048] If the convergence value is less than the preset convergence threshold, then determine whether the number of volt-ampere test curves has reached the preset cycle threshold.

[0049] If yes, then generate and display the unstable test result information; if no, then adjust the time interval of the current voltage value input to the field emission device according to the preset delay ratio, and return to the initial step.

[0050] The convergence value is calculated by comparing the current volt-ampere test curve with the previous volt-ampere test curve after each scan and using the curve similarity as the convergence value. If the convergence value is ≥95%, it is considered converged; if the convergence value is lower than 95% (i.e., the deviation exceeds 5%), it is considered non-converged. The preset convergence threshold (default 95%) can be adjusted by the user according to experimental needs.

[0051] If the test is determined to be non-convergent, the sampling time or sampling interval (i.e., the time interval between two adjacent inputs of the current voltage value) will be extended. The default initial sampling interval is 500ms. After each round of non-convergent testing, the sampling interval will be increased by a preset delay ratio (default 5%) based on the previous round. The next round of testing will be started after adjustment.

[0052] Furthermore, if the similarity of the two consecutive volt-ampere test curves reaches or exceeds 95%, the test is considered to have converged and the loop ends; if the loop reaches the maximum number of rounds (default 10 rounds) and still has not converged, an unstable test result message is generated and the test is terminated.

[0053] The above embodiments can determine the convergence and preset cycle threshold of the obtained volt-ampere test curve after the detected current value reaches the preset current test threshold, so as to ensure the stability and repeatability of subsequent data analysis and processing.

[0054] Furthermore, the above-mentioned FN transform and linear fitting of the volt-ampere test curve yields a test result report, including: Step S61: Perform FN transformation on the volt-ampere test curve to obtain the FN curve.

[0055] Specifically, in this step, the original current-voltage (IV) test curves are transformed using the Fowler–Nordheim (F–N) mathematical transformation, converting the ordinate to ln(I / V²) and the abscissa to I / V. This transformation linearizes the exponential relationship of the field emission current, facilitating subsequent linear fitting and parameter extraction. An F–N curve is then plotted based on the transformation result. This curve provides a visual basis for subsequent analysis and serves as a comparison with the current-voltage (IV) test curves to check the consistency and rationality of the data.

[0056] Step S62: Perform linear fitting on one or more segments of the FN curve to obtain fitting parameters and outlier information.

[0057] Specifically, such as Figure 4 As shown, in single-segment fitting mode, a linear fit is performed on the entire voltage scan range; in multi-segment fitting mode, the FN curve is divided into multiple intervals, and linear fits are performed on each interval separately to better reflect the emission characteristics of different intervals. During the fitting process, fitting parameters such as slope, intercept, correlation coefficient, and goodness of fit are output.

[0058] Simultaneously, during the fitting process, the residual distribution and current abrupt changes are considered to identify outliers. Examples include: sudden current jumps (flickering or discharge events); data points that significantly deviate from the linear trend (if the residual of a data point deviates from the fitted value by more than 20%, it is considered a deviation from the linear trend and marked as an outlier. The judgment threshold can be adjusted manually; the default here is 20%); and non-physical points caused by equipment range switching. These outliers are marked on the curve.

[0059] Step S63: Generate a test result report based on the volt-ampere test curve, FN curve, fitting parameters, and outlier information.

[0060] After processing, this application will output a test result report, which includes the original volt-ampere test curve, the converted FN curve, fitting parameters, field enhancement factor, effective work function, outlier information, etc. The test result report can be exported as PDF, CSV, or other formats, and includes timestamps and hash verification information to ensure traceability.

[0061] Please see Figure 5 Another embodiment of this application provides a field emission current-voltage characteristic testing device, comprising: The determination module 101 is used to determine the voltage scanning range and the current step voltage based on user input parameters or preset default parameters.

[0062] The initial module 102 is used to initialize the voltage-current test curve, taking the minimum value of the voltage scan range as the current voltage value.

[0063] Test module 103 is used to input the current voltage value into the field emission device to obtain the detection current value.

[0064] The plotting module 104 is used to update the volt-ampere test curve based on the current voltage value and the detected current value.

[0065] The output judgment module 105 is used to determine whether the detected current value is greater than the preset current test threshold.

[0066] The data processing module 106 is used to perform FN transformation and linear fitting on the volt-ampere test curve when the detected current value is greater than the preset current test threshold, and to obtain a test result report.

[0067] The adaptive module 107 is used to add the current voltage value and the current step voltage to obtain the updated current voltage value when the detected current value is less than or equal to the preset current test threshold; calculate the current change rate according to the volt-ampere test curve; and update the current step voltage according to the current change rate.

[0068] The loop module 108 is used to determine whether the updated current voltage value exceeds the voltage scanning range; if so, the voltage scanning range is updated according to the preset expansion ratio and the module is returned to the initial module; if not, the module is returned to the test module.

[0069] The specific limitations of the field emission current-voltage characteristic testing device provided in this embodiment can be found in the embodiment of the field emission current-voltage characteristic testing method described above, and will not be repeated here. Each module in the above-described field emission current-voltage characteristic testing device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device in hardware form, or stored in the memory of a computer device in software form, so that the processor can call and execute the operations corresponding to each module.

[0070] This application provides a computer device that may include a processor, memory, network interface, and database connected via a system bus. The processor provides computing and control capabilities. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores an operating system, computer programs, and a database. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The network interface communicates with external terminals via a network connection. When the computer program is executed by the processor, it causes the processor to perform the steps of a field emission current-voltage characteristic testing method as described in any of the above embodiments.

[0071] The working process, working details, and technical effects of the computer device provided in this embodiment can be found in the embodiment of a field emission current-voltage characteristic test method described above, and will not be repeated here.

[0072] This application provides a computer-readable storage medium storing a computer program thereon. When executed by a processor, the computer program implements the steps of a field emission current-voltage characteristic testing method as described in any of the above embodiments. The computer-readable storage medium refers to a data storage carrier, which may include, but is not limited to, floppy disks, optical disks, hard disks, flash memory, USB flash drives, and / or Memory Sticks. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The working process, details, and technical effects of the computer-readable storage medium provided in this embodiment can be found in the embodiments of a field emission current-voltage characteristic testing method described above, and will not be repeated here.

[0073] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), RAMbus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and RAMbus dynamic RAM (RDRAM).

[0074] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0075] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A field emission voltammetric characteristic test method, characterized by, The method comprises the following steps: determining a voltage scanning range and a current step voltage according to user input parameters or preset default parameters; an initial step of initializing a volt-ampere test curve, taking the minimum value of the voltage scanning range as a current voltage value; a test step of inputting the current voltage value into a field emission device to obtain a detection current value; updating the volt-ampere test curve according to the current voltage value and the detection current value; judging whether the detection current value is greater than a preset current test threshold value; if yes, performing F-N transformation and linear fitting on the volt-ampere test curve to obtain a test result report; if no, adding the current voltage value and the current step voltage to obtain an updated current voltage value; calculating a current change rate according to the volt-ampere test curve and updating the current step voltage according to the current change rate; judging whether the updated current voltage value exceeds the voltage scanning range; if yes, updating the voltage scanning range according to a preset expansion ratio and returning to the initial step; if no, returning to the test step.

2. The field emission voltammetric test method according to claim 1, wherein The method of determining a voltage scanning range and a current step voltage according to user input parameters or preset default parameters comprises the following steps: judging whether the user input parameters exist; if yes, judging whether the user input parameters meet preset test standards; if yes, determining a voltage scanning range and a current step voltage according to user input parameters; if no or the user input parameters do not exist, determining a voltage scanning range and a current step voltage according to preset default parameters.

3. The field emission voltammetric test method according to claim 1, wherein The method further comprises the following steps: after the test step is performed, judging whether the detection current value exceeds a current safety threshold value; if yes, performing a power-off operation on the field emission device; if no, updating the volt-ampere test curve.

4. The field emission voltammetric test method according to claim 1, wherein The method further comprises the following steps: if the detection current value is greater than a preset current test threshold value, obtaining a volt-ampere test curve corresponding to the previous voltage scanning range as a historical test curve; judging a convergence value of the volt-ampere test curve according to the historical test curve; if the convergence value is greater than or equal to a preset convergence threshold value, performing F-N transformation and linear fitting on the volt-ampere test curve.

5. The field emission voltammetric test method according to claim 4, wherein The method further comprises the following steps: if the convergence value is less than a preset convergence threshold value, judging whether the number of volt-ampere test curves reaches a preset cycle threshold value; if yes, generating test result instability information and displaying; if no, adjusting a time interval of inputting the current voltage value into the field emission device according to a preset delay ratio and returning to the initial step.

6. The field emission voltammetric test method of claim 1, wherein The method of performing F-N transformation and linear fitting on the volt-ampere test curve to obtain a test result report comprises the following steps: performing F-N transformation on the volt-ampere test curve to obtain an F-N curve; performing one or more linear fittings on the F-N curve to obtain fitting parameters and abnormal point information; generating a test result report based on the volt-ampere test curve, the F-N curve, the fitting parameters and the abnormal point information.

7. The field emission voltammetric test method of claim 1, wherein The method of updating the current step voltage according to the current change rate comprises the following steps: The first change threshold, the second change threshold and the step voltage adjustment ratio are acquired; if the current change rate is less than or equal to the first change threshold, the current step voltage is increased according to the step voltage adjustment ratio; if the current change rate is greater than the first change threshold and less than or equal to the second change threshold, the current step voltage remains unchanged; and if the current change rate is greater than the second change threshold, the current step voltage is increased or decreased according to the step voltage adjustment ratio.

8. A field emission voltammetric characteristic testing device, characterized by comprising: The method comprises the following steps: A determining module is configured to determine a voltage scanning range and a current step voltage according to user input parameters or preset default parameters; An initializing module is configured to initialize a volt-ampere test curve, and take a minimum value of the voltage scanning range as a current voltage value; A testing module is configured to input the current voltage value into a field emission device to obtain a detection current value; A drawing module is configured to update the volt-ampere test curve according to the current voltage value and the detection current value; An output judging module is configured to judge whether the detection current value is greater than a preset current test threshold; A data processing module is configured to, when the detection current value is greater than the preset current test threshold, perform F-N transformation and linear fitting on the volt-ampere test curve to obtain a test result report; An adaptive module is configured to, when the detection current value is less than or equal to the preset current test threshold, add the current voltage value and the current step voltage to obtain an updated current voltage value; A current change rate is calculated according to the volt-ampere test curve, and the current step voltage is updated according to the current change rate; A loop module is configured to judge whether the updated current voltage value exceeds the voltage scanning range; if yes, the voltage scanning range is updated according to a preset expansion ratio, and the method returns to the initializing module; and if no, the method returns to the testing module.

9. A computer device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, The processor executes the computer program to implement the steps of the field emission volt-ampere characteristic test method according to any one of claims 1 to 7.

10. A computer-readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to implement the steps of the field emission volt-ampere characteristic test method according to any one of claims 1 to 7.

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