Method and system for detecting displacement defects in a metal semiconductor field effect transistor

Abstract

This invention provides a method and system for detecting displacement defects in metal-semiconductor field-effect transistors (MESFETs), relating to the field of semiconductor testing. By inputting defect parameters into a displacement defect model, it is equivalent to assuming the defect is a displacement defect, obtaining a simulated curve. This simulated curve represents the MESFET device under displacement defect conditions. The simulated curve is compared with the performance curve obtained through actual testing. When the simulated curve matches the performance curve, it can be verified that a displacement defect has occurred in the tested MESFET device. Using this method to test MESFET devices eliminates the need for multiple annealing tests for verification. Only electrical performance testing of the device under test is performed to obtain a performance curve, which is then compared with the simulated curve obtained through simulation for corroboration. This allows for accurate detection of displacement defects and improves the detection speed.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor detection, in particular to a method and system for detecting displacement defects in a metal semiconductor field effect transistor. BACKGROUND

[0002] Various factors in the space environment can affect the on-orbit operation of a spacecraft, especially the radiation environment, which can cause serious damage to the functions of electronic components in the spacecraft. In a harsh space radiation environment, different charged particles and rays cause different performance damage to electronic devices. Some radiation damage is transient (such as ionization damage), and some radiation damage is permanent (such as displacement damage). Permanent radiation damage is often fatal to the on-orbit operation of a spacecraft.

[0003] Displacement damage is caused by high-energy particles incident on the interior of a semiconductor material or device, colliding with lattice atoms and exchanging energy, thereby causing lattice atoms to leave their original positions and generating interstitial atoms and vacancies. In the subsequent time, the interstitial and vacancy may evolve into complex composite defects, causing semi-permanent or permanent damage to the semiconductor material and device. Displacement defects mainly affect the performance of semiconductor materials or devices by reducing carrier mobility, trapping carriers, and reducing carrier lifetime. Metal semiconductor field effect transistors (MESFETs) and related integrated circuits (such as MMICs) are widely used in satellite communication, radar navigation, electronic warfare and other systems due to their high speed and high frequency characteristics. Since the MESFET process technology (semiconductor device active layer under the gate, forming a Schottky contact) does not involve an oxide layer, it is not sensitive to ionizing effects, and the displacement damage caused by various radiation particles to the MESFET device needs to be focused on.

[0004] Currently, the deep level transient spectrometer (DLTS) is the most effective method for detecting the energy level, defect concentration, and capture cross section of radiation damage defects in semiconductor materials and electronic devices. However, determining the defect type (referring to ionization and displacement defects) detected by DLTS is a very complex problem. Usually, multiple annealing experiments need to be combined with isothermal and isochronal to verify and confirm, which requires a lot of manpower and resources. SUMMARY

[0005] The problem to be solved by the present application is how to quickly determine the type of defects in a metal semiconductor field effect transistor.

[0006] To solve the above problems, on the one hand, the present application provides a method for detecting displacement defects in a metal semiconductor field effect transistor, comprising:

[0007] Adjusting a test parameter, detecting the irradiated to-be-tested element, and obtaining a defect parameter and a performance curve of the to-be-tested element;

[0008] Inputting the defect parameter into a displacement defect model to obtain a simulation curve;

[0009] Judging whether the performance curve is consistent with a trend of the simulation curve;

[0010] If yes, the defect of the to-be-tested element is a displacement defect.

[0011] Further, the adjusting a test parameter, detecting the irradiated to-be-tested element, and obtaining a defect parameter and a performance curve of the to-be-tested element comprises:

[0012] Setting a filling pulse voltage, a pulse width and a test period at the time of testing, scanning the to-be-tested element by changing a reverse bias voltage, and obtaining the test curve;

[0013] Comparing the obtained test curve, and judging whether a signal peak in the test curve changes, wherein the signal peak is a mutation position in the test curve;

[0014] If the signal peak in the test curve does not change, the defect parameter is obtained according to the position of the signal peak.

[0015] Further, the adjusting a test parameter, detecting the irradiated to-be-tested element, and obtaining a defect parameter and a performance curve of the to-be-tested element further comprises:

[0016] Selecting an irradiation source, controlling a range of the irradiation source, and irradiating the to-be-tested element, wherein the irradiation source comprises protons or heavy ions, and an end point of the range of the irradiation source is in an active layer below a gate electrode;

[0017] Performing a performance test on the irradiated to-be-tested element to obtain a performance curve.

[0018] Further, the inputting the defect parameter into a displacement defect model to obtain a simulation curve specifically comprises:

[0019] Establishing a structure model of the to-be-tested element corresponding to an irradiation test, wherein the structure model calls the displacement defect model;

[0020] Inputting the defect parameter into the displacement model to obtain a recombination rate;

[0021] Simulating a transfer characteristic of the to-be-tested element using the recombination rate to obtain the simulation curve.

[0022] Further, the displacement defect model comprises:

[0023]

[0024] In the formula, U SRH represents the recombination rate, τ n , τ p respectively represent the lifetime of electrons, holes, p, n respectively represent the concentration of holes, electrons, n ie represents the effective intrinsic carrier concentration, E i represents the intrinsic Fermi level, E T represents the defect energy level, k B represents the Boltzmann constant, and T represents the thermodynamic temperature.

[0025] In another aspect, the present application also provides a system for detecting displacement defects in a metal semiconductor field effect transistor, characterized in that it comprises:

[0026] a testing device for adjusting testing parameters, detecting an irradiated to-be-tested element, and obtaining defect parameters and performance curves of the to-be-tested element;

[0027] a simulation module for inputting the defect parameters into a displacement defect model to obtain simulation curves, and judging whether the performance curves coincide with the trend of the simulation curves; if so, the defects of the to-be-tested element are displacement defects.

[0028] Further, the testing device comprises:

[0029] a testing unit for setting filling pulse voltage, pulse width and testing period during testing, scanning the to-be-tested element by changing reverse bias voltage, and obtaining the testing curves;

[0030] a comparison unit for comparing the obtained testing curves, judging whether the signal peaks in the testing curves change, wherein the signal peaks are mutation positions in the testing curves; if the signal peaks in the testing curves do not change, the defect parameters are obtained according to the positions of the signal peaks.

[0031] Further, the system for detecting displacement defects in a metal semiconductor field effect transistor further comprises:

[0032] an irradiation device for selecting an irradiation source, controlling the range of the irradiation source, irradiating the to-be-tested element, wherein the irradiation source comprises protons or heavy ions, and the range end of the irradiation source is in the active layer below the gate; and for testing the performance of the irradiated to-be-tested element to obtain performance curves.

[0033] Further, the simulation module comprises:

[0034] A structure model building unit is configured to build a structure model of the to-be-tested element corresponding to the irradiation test, wherein the displacement defect model is called in the structure model;

[0035] A simulation unit is configured to input the defect parameter into the displacement model to obtain a recombination rate, and simulate the transfer characteristic of the to-be-tested element using the recombination rate to obtain the simulation curve.

[0036] Further, the displacement defect model comprises:

[0037]

[0038] In the formula, U SRH represents the recombination rate, τ n , τ p represent the lifetime of the electron and the hole respectively, p and n represent the concentration of the hole and the electron respectively, n ie represents the effective intrinsic carrier concentration, E i represents the intrinsic Fermi level, E T represents the defect energy level, k B represents the Boltzmann constant, and T represents the thermodynamic temperature.

[0039] Compared with the prior art, the present application has the following beneficial effects:

[0040] The present application provides a method and system for detecting displacement defects in a metal semiconductor field effect transistor (MESFET),

[0041] By inputting the defect parameter into the displacement defect model, it is equivalent to assuming that the defect is a displacement defect, and a simulation curve is obtained. The simulation curve is obtained under the condition that the MESFET device has displacement defects. When the simulation curve and the performance curve obtained by actual testing are compared, the MESFET device under test is verified to have displacement defects when the simulation curve and the performance curve coincide. By using this method to detect the MESFET device, it is not necessary to verify and confirm by multiple annealing tests. Only the electrical performance test of the to-be-tested element is performed to obtain the performance curve, which is compared with the simulation curve obtained by simulation to accurately detect the displacement defects and improve the detection speed. BRIEF DESCRIPTION OF DRAWINGS

[0042] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are some embodiments of the present application, and those skilled in the art can obtain other drawings according to these drawings without creative labor.

[0043] Figure 1 A flowchart of a method for detecting displacement defects in a metal-semiconductor field-effect transistor according to an embodiment of the present invention is shown;

[0044] Figure 2 The deep-level transient spectrum of the MESFET device obtained by testing in an embodiment of the present invention is shown.

[0045] Figure 3 The figure shows the variation of the number of vacancy numbers in the MESFET device after proton irradiation with the incident depth in an embodiment of the present invention.

[0046] Figure 4 The electrical characteristic curves of the MESFET device under different irradiation doses in the embodiments of the present invention are shown.

[0047] Figure 5 A schematic diagram of the simulation curve in an embodiment of the present invention is shown. Detailed Implementation

[0048] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0049] Figure 1 A flowchart of a method for detecting displacement defects in a metal-semiconductor field-effect transistor (MOSFET) according to an embodiment of the present invention is shown. The method for detecting displacement defects in a metal-semiconductor field-effect transistor includes:

[0050] Step 1: Adjust the test parameters and test the irradiated component under test (DUT) to obtain its defect parameters and performance curves. The test parameters of the testing device are adjusted once. After the initial adjustment, repeated adjustments are not required when testing the same or similar MESFET devices in the same experiment or within a short period. Alternatively, the initial adjustment can be done manually, and the manually adjusted test parameters can be saved to the testing device. Subsequent tests with the same or similar devices can then be performed automatically using the saved test parameters. In this embodiment, the DUT refers to a MESFET device; however, this method can also be applied to the testing of other similar or applicable devices.

[0051] Step 2: Input the defect parameters into the displacement defect model to obtain the simulation curve. The simulation curve is the transfer characteristic curve of the MESFET device output in simulation mode. Input the same defect parameters, assuming the defect is a displacement defect, and input the defect parameters obtained in the previous step into the constructed displacement defect model. This is equivalent to a reverse verification to see what the simulation curve looks like when the defect is assumed to be a displacement defect.

[0052] Step 3: Determine whether the performance curve matches the trend of the simulation curve. It should be noted that "match" here does not mean complete overlap; some deviation is allowed. The main focus here is whether the trends of the two curves are consistent. These trends can be determined by the inflection points, growth rates, fluctuations, and slopes of the curves.

[0053] Step 4: If yes, then the defect of the component under test is a displacement defect. If not, then the defect of the component under test is not a displacement defect, but may be an ionization damage defect or other defects.

[0054] Assuming the defect is a displacement defect, a simulated curve is obtained by inputting the defect parameters into the displacement defect model. This simulated curve represents the MESFET device under displacement defect conditions. The simulated curve is compared with the performance curve obtained through actual testing. When the simulated curve matches the performance curve, it verifies that a displacement defect has occurred in the tested MESFET device. Using this method to test MESFET devices eliminates the need for multiple annealing tests for verification. Only electrical performance tests are performed on the device under test to obtain a performance curve, which is then compared with the simulated curve for corroboration. This allows for accurate detection of displacement defects and improves detection speed. This method plays a crucial role in rapidly identifying displacement defects caused by protons or heavy ions in MESFET devices.

[0055] In one embodiment of the present invention, adjusting the test parameters to test the irradiated component under test and obtaining the defect parameters and performance curves of the component under test specifically includes:

[0056] The fill pulse voltage, pulse width, and test period are set during the test. By changing the reverse bias voltage, the device under test is scanned to obtain the test curve.

[0057] The obtained test curves are compared to determine whether the signal peaks in the test curves have changed, wherein the signal peaks are the abrupt change positions in the test curves.

[0058] If the signal peak in the test curve does not change, the defect parameters are obtained based on the position of the signal peak. The defect parameters include defect information such as defect energy level, defect concentration, and defect trapping cross section.

[0059] In this embodiment, the gate-source diode structure in the MESFET is used as the Schottky junction under test, and a suitable fill pulse voltage (V) is selected. P ), pulse width (T) P ), test cycle (T) W Then only change the reverse bias voltage (V) R If the position of the signal peak in the obtained temperature scan test curve does not change with the reverse bias voltage, then the defect generated within the MESFET device is a displacement defect. Figure 2 As shown, after 150keV low-energy proton irradiation, two types of acceptor defects (defects generated at the two signal peaks) are generated in the GaAs MESFET device. These two acceptor defects can trap electrons in the active region of the MESFET, reducing the number of electrons. Simultaneously, the trapping also reduces carrier mobility, further decreasing the source and drain current of the device, leading to threshold voltage drift. To save time and reduce resource waste, the signal peaks that may be caused by displacement defects can be located in the test curves first. Tests can be performed by changing the reverse bias voltage, and the test curves obtained under different reverse bias voltages can be compared. The defect parameters corresponding to the signal peaks with unchanged positions can then be input into the displacement defect model.

[0060] In one embodiment of the present invention, before adjusting the test parameters to test the irradiated component under test and obtaining the defect parameters and performance curve of the component under test, the method further includes:

[0061] An irradiation source is selected, and the range of the irradiation source is controlled to irradiate the device under test. The irradiation source includes protons or heavy ions, and the end point of the range of the irradiation source is in the active layer below the gate.

[0062] The performance of the irradiated component under test was tested to obtain a performance curve.

[0063] High-energy charged particles in space include electrons, protons, and heavy ions, as well as light radiation environments such as X-rays and gamma rays. Damage to electronic devices is mainly classified into ionization damage and displacement damage.

[0064] Specifically, based on the structural dimensions of the MESFET device used in the irradiation test, a proton or heavy ion source with appropriate energy is selected for incident radiation, and its range end is controlled to be in the GaAs active layer below the gate, so as to avoid the gate metal not being able to be penetrated due to too low energy. Figure 3The relationship between vacancy generation and incident depth after a 150 keV proton bombardment of a MESFET device is shown. Clearly, 150 keV low-energy protons can penetrate the MESFET device used in the irradiation experiment, and the end of their range is within the active layer of the device. Therefore, 150 keV protons can be selected as the radiation source for studying displacement defects in MESFET devices. Subsequently, the normalized electrical characteristic curves of the device under different irradiation fluences were measured, as shown below. Figure 4 As shown, it can be seen that with the increase of proton irradiation flux, the threshold voltage of the device shifts positively, and the source and drain currents gradually decrease. This is because the displacement effect generates recombination centers in the bandgap of the semiconductor. These recombination centers capture the majority carriers in the device (such as electrons in a MESFET). At the same time, the displacement effect forms scattering centers, reducing the mobility of carriers, thereby reducing the source and drain currents and causing the threshold voltage to drift.

[0065] In one embodiment of the present invention, the step of inputting the defect parameters into the displacement defect model to obtain the simulation curve specifically includes:

[0066] A structural model of the test element corresponding to the irradiation test is established, wherein the displacement defect model is called in the structural model.

[0067] The defect parameters are input into the displacement model to obtain the composite rate;

[0068] The transfer characteristics of the device under test are simulated using the recombination rate to obtain the simulation curve.

[0069] In this embodiment, a mathematical model is constructed using equations that can run on any semiconductor device. These equations relate electrostatic potential and carrier concentration within a specific simulation region. These equations, derived from Maxwell's laws and consisting of the Poisson equation and continuity equations (including transport equations), can be solved in any general-purpose device simulator. The simulation of the conventional electrical characteristics of the semiconductor device involves solving the Poisson and continuity equations to obtain the distribution of electrostatic potential, carrier concentration, and other physical quantities at each grid node in the discretized device region. This distribution is presented in the form of current and voltage characteristics. Plotting the obtained electrical parameters yields the simulation results of the semiconductor device's electrical characteristics.

[0070] The formula for the Poisson equation is:

[0071] div(ε▽ψ)=-ρ(1)

[0072] Where ψ is the electrostatic potential; ε is the dielectric constant; and ρ is the space charge density, which is the sum of all moving and stationary charges, including electrons, holes, and ionized impurities.

[0073] The intensity of the electric field in the device can be obtained from the potential gradient:

[0074]

[0075] The carrier continuity equation is divided into the electron continuity equation and the hole continuity equation, as shown in the following formula:

[0076]

[0077]

[0078] Where n is the electron concentration; p is the hole concentration; and These are the densities of electron and hole currents, respectively; G n and G p These are the generation rates of electrons and holes, respectively; R n and R p q and q represent the recombination rates of electrons and holes, respectively, and q is the charge of an electron.

[0079] The addition of various physical models in the simulation of the electrical characteristics of semiconductor devices is actually a matter of modifying the parameters and terms in formulas (1) to (4) to reflect the corresponding physical effects. The displacement defect model is achieved by introducing the recombination rate in formulas (3) and (4). The displacement defect model is based on the SRH recombination model. Assuming that the transport process satisfies Boltzmann statistics, the formula for the acceptor-type displacement defect model is:

[0080]

[0081] In the formula, U SRH τ represents the recombination rate. n τ p Let p and n represent the lifetimes of electrons and holes, respectively, and let n represent the concentrations of holes and electrons, respectively. ie E represents the effective intrinsic carrier concentration. i E represents the intrinsic Fermi level. T Denotes the defect energy level, k B denoted by Boltzmann constant, and T represents thermodynamic temperature.

[0082] It should be noted that the recombination rate R of electrons in formulas (3) and (4) n The recombination rate R of holes p It is obtained from the displacement defect model. The recombination rate obtained in formula (5) is combined with formulas (1)-(4) to obtain the electrical characteristic curve of the simulated semiconductor device.

[0083] A structural model of the GaAs MESFET device used in the irradiation test was established. The defect parameters corresponding to the measured signal peaks were used as input parameters for the displacement defect model. Then, the transfer characteristics of the device were simulated. The normalized transfer characteristic curves obtained from the simulation are shown below. Figure 5 As shown. Comparison Figure 4 1*10 12 p / cm 2 Electrical characteristic curves of MESFET devices under flux and Figure 5 1*10 obtained from simulation 12 p / cm 2 The simulation curves under the injection pressure show that the simulation results of the passive displacement defect model are in good agreement with the actual test results. This not only verifies the feasibility of the displacement defect model, but also proves the feasibility of quickly identifying whether the generated defect is a displacement defect by changing the reverse bias, which has important engineering significance.

[0084] In one embodiment of the present invention, a detection system for displacement defects in a metal-semiconductor field-effect transistor is also designed, comprising:

[0085] The testing apparatus is used to adjust the testing parameters and inspect the irradiated component under test (SUT) to obtain its defect parameters and performance curves. The testing apparatus can be a deep-level transient spectroscopy (DLTS) device and a semiconductor parameter analyzer, used to obtain defect parameters and performance curves respectively, or other equipment with the same function as the testing apparatus can be selected.

[0086] The simulation module is used to input the defect parameters into the displacement defect model to obtain the simulation curve; it is also used to determine whether the performance curve matches the trend of the simulation curve; if so, the defect of the component under test is a displacement defect. The simulation module can use self-developed TCAD software, and by calling the displacement defect model in the self-developed TCAD software, it can verify that the defect induced by proton or heavy ion irradiation is a displacement defect.

[0087] This invention focuses on the study of displacement defects in the active layer of a metal-semiconductor field-effect transistor (MESFET). It employs protons or heavy ions as the radiation source to induce displacement damage. The main method involves changing the reverse bias voltage V by modifying the parameters of the testing device. R This method allows for the rapid identification of displacement defects generated by protons and heavy ions in MESFET devices. Then, by combining this with self-developed TCAD software and calling the displacement defect model, it is proven that the defects caused by irradiation are indeed displacement-related defects. This method has significant engineering value for rapidly identifying displacement defects generated by protons and heavy ions in MESFET devices, improving detection speed and accuracy.

[0088] In one embodiment of the present invention, the testing apparatus includes:

[0089] The test unit is used to set the fill pulse voltage, pulse width and test period during the test. By changing the reverse bias voltage, the test component is scanned to obtain the test curve.

[0090] The comparison unit is used to compare the obtained test curves and determine whether the signal peaks in the test curves have changed, wherein the signal peaks are the abrupt change positions in the test curves; if the signal peaks in the test curves have not changed, the defect parameters are obtained according to the position of the signal peaks.

[0091] In this embodiment, deep-level transient spectrum (DLTS) testing is performed on the irradiated MESFET device. To quickly determine whether the irradiation-induced defect type is a displacement defect, the DLTS test parameters are changed to rapidly identify the defect type generated by the radiation source. Specifically, the test method involves using the gate-source diode structure in the MESFET as the Schottky junction under test, and selecting an appropriate fill pulse voltage (V0). P ), pulse width (T) P ), test cycle (T) W Then only change the reverse bias voltage (V) R If the position of the signal peak of the obtained temperature scan test curve does not change with the reverse bias voltage, then the defect generated in the MESFET device is a displacement defect.

[0092] The displacement defect detection system in the metal-semiconductor field-effect transistor also includes:

[0093] An irradiation device is used to select an irradiation source, control the range of the irradiation source, and irradiate the device under test (DUT). The irradiation source includes protons or heavy ions, and the range of the irradiation source ends in the active layer below the gate. It is also used to perform performance testing on the irradiated DUT to obtain performance curves. The irradiation device can be composed of SRIM software combined with a semiconductor parameter analyzer. SRIM software calculates, based on the structural dimensions of the MESFET device used in the irradiation test, the appropriate energy of a proton or heavy ion source for incident radiation. SRIM (Stopping and Range of Ionsin Matter) is software that can calculate stopping power and the incident range of ions in a substance. The semiconductor parameter analyzer can be used to measure the electrical characteristic curves (i.e., performance curves) of the MESFET device in actual irradiation tests.

[0094] In one embodiment of the present invention, the simulation module includes:

[0095] The structural model building unit is used to establish a structural model of the device under test corresponding to the irradiation test, wherein the displacement defect model is called in the structural model. A structural model of the MESFET device used in the irradiation test is also established.

[0096] The simulation unit is used to input the defect parameters into the displacement model to obtain the recombination rate; the recombination rate is used to simulate the transfer characteristics of the device under test to obtain the simulation curve. The defect parameters corresponding to the defect peaks measured by DLTS are used as input parameters for the displacement defect model called in the self-developed TCAD software, and then the transfer characteristics of the device are simulated.

[0097] In addition to calling the displacement defect model, the structural model also calls other mathematical models, which consist of equations including solving the Poisson equation and the continuity equation. The continuity equation further includes the electron continuity equation and the hole continuity equation. Solving the Poisson equation and the continuity equation yields the distribution of electrostatic potential, carrier concentration, and other physical quantities at each grid node in the discretized device region, which are then presented in the form of current and voltage characteristics. Plotting the obtained electrical parameters gives the simulation results of the electrical characteristics of the semiconductor device.

[0098] The formula for the Poisson equation is as follows:

[0099] div(ε▽ψ)=-ρ(1)

[0100] Where ψ is the electrostatic potential; ε is the dielectric constant; and ρ is the space charge density, which is the sum of all moving and stationary charges, including electrons, holes, and ionized impurities.

[0101] The intensity of the electric field in the device can be obtained from the potential gradient:

[0102]

[0103] The carrier continuity equation is divided into the electron continuity equation and the hole continuity equation, and the formulas are as follows:

[0104]

[0105]

[0106] Where n is the electron concentration; p is the hole concentration; and These are the densities of electron and hole currents, respectively; G n and G p These are the generation rates of electrons and holes, respectively; R n and R pq and q represent the recombination rates of electrons and holes, respectively, and q is the charge of an electron.

[0107] The addition of various physical models in the simulation of the electrical characteristics of semiconductor devices is actually a matter of modifying the parameters and terms in formulas (1) to (4) to reflect the corresponding physical effects. The displacement defect model is achieved by introducing the recombination rate in formulas (3) and (4). The displacement defect model is based on the SRH recombination model. Assuming that the transport process satisfies Boltzmann statistics, the formula for the acceptor-type displacement defect model is:

[0108]

[0109] In the formula, U SRH τ represents the recombination rate. n τ p Let p and n represent the lifetimes of electrons and holes, respectively, and let n represent the concentrations of holes and electrons, respectively. ie E represents the effective intrinsic carrier concentration. i E represents the intrinsic Fermi level. T Denotes the defect energy level, k B denoted by Boltzmann constant, and T represents thermodynamic temperature.

[0110] It should be noted that the recombination rate R of electrons in formulas (3) and (4) n The recombination rate R of holes p It is obtained from the displacement defect model. The recombination rate obtained in formula (5) is combined with formulas (1)-(4) to obtain the electrical characteristic curve of the simulated semiconductor device.

[0111] TCAD software is a numerical simulation tool built on the foundation of semiconductor physics. It can simulate different process conditions, replacing or partially replacing expensive and time-consuming process experiments; it can also optimize different device structures to obtain ideal characteristics; and it can simulate circuit performance and reliability issues caused by various external environments (including extreme environments such as high temperature and radiation). By viewing the simulation results, changes in physical quantities that are difficult to observe directly in actual experiments can be obtained, thus gaining deeper insights. These analyses and results can, in turn, guide process flow and device design to develop semiconductor devices with superior performance.

[0112] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for detecting displacement defects in a metal-semiconductor field-effect transistor, characterized in that, include: The test parameters are adjusted to test the irradiated component under test (DUT) to obtain its defect parameters and performance curves. This includes setting the fill pulse voltage, pulse width, and test period during the test; scanning the DUT by changing the reverse bias voltage to obtain the test curves; comparing the obtained test curves to determine if the signal peaks in the test curves have changed, where the signal peaks are the abrupt change points in the test curves; if the signal peaks in the test curves have not changed, the defect parameters are obtained based on the position of the signal peaks. The defect parameters are input into the displacement defect model to obtain a simulation curve. This includes establishing a structural model of the test element corresponding to the irradiation test, wherein the displacement defect model is called in the structural model; inputting the defect parameters into the displacement defect model to obtain the recombination rate; and using the recombination rate to simulate the transfer characteristics of the test element to obtain the simulation curve. The displacement defect model includes: ， In the formula, Indicates the composite rate, , These represent the lifetimes of electrons and holes, respectively. , These represent the concentrations of holes and electrons, respectively. Indicates the effective intrinsic carrier concentration. Indicates the intrinsic Fermi level. Indicates the defect energy level. Represents the Boltzmann constant. Represents thermodynamic temperature; Determine whether the performance curve matches the trend of the simulation curve; If so, then the defect of the component under test is a displacement defect.

2. The method for detecting displacement defects in a metal-semiconductor field-effect transistor according to claim 1, characterized in that, The process of adjusting test parameters to detect the irradiated component under test and obtaining its defect parameters and performance curves also includes: An irradiation source is selected, and the range of the irradiation source is controlled to irradiate the device under test. The irradiation source includes protons or heavy ions, and the end point of the range of the irradiation source is in the active layer below the gate. The performance of the irradiated component under test was tested to obtain a performance curve.

3. A system for detecting displacement defects in a metal-semiconductor field-effect transistor, characterized in that, include: A testing device is used to adjust test parameters to test an irradiated component under test (DUT) and obtain its defect parameters and performance curves. The testing device includes: a testing unit for setting the fill pulse voltage, pulse width, and test period during testing; scanning the DUT by changing the reverse bias voltage to obtain a test curve; and a comparison unit for comparing the obtained test curves to determine whether the signal peaks in the test curves have changed, wherein the signal peaks are abrupt changes in the test curves; if the signal peaks in the test curves have not changed, the defect parameters are obtained based on the position of the signal peaks. A simulation module is used to input the defect parameters into a displacement defect model to obtain a simulation curve; it is also used to determine whether the performance curve matches the trend of the simulation curve; if so, the defect of the component under test is a displacement defect; the simulation module includes: a structural model building unit, used to establish a structural model of the component under test corresponding to the irradiation test, wherein the displacement defect model is called in the structural model; a simulation unit, used to input the defect parameters into the displacement defect model to obtain the recombination rate; and to use the recombination rate to simulate the transfer characteristics of the component under test to obtain the simulation curve; the displacement defect model includes: ， In the formula, Indicates the composite rate, , These represent the lifetimes of electrons and holes, respectively. , These represent the concentrations of holes and electrons, respectively. Indicates the effective intrinsic carrier concentration. Indicates the intrinsic Fermi level. Indicates the defect energy level. Represents the Boltzmann constant. It represents thermodynamic temperature.

4. The detection system for displacement defects in a metal-semiconductor field-effect transistor according to claim 3, characterized in that, Also includes: An irradiation device is used to select an irradiation source, control the range of the irradiation source, and irradiate the device under test, wherein the irradiation source includes protons or heavy ions, and the end point of the range of the irradiation source is in the active layer below the gate. It is also used to perform performance testing on the irradiated component under test to obtain a performance curve.

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