Modeling Method and Model for Linear Variable Resistance in the Drift Region of Superjunction MOSFET Devices

Abstract

This invention relates to a method and model for modeling the linear variable resistance in the drift region of a superjunction MOSFET device. The method includes: constructing a superjunction MOSFET circuit model, which consists of a MOSFET, a linear variable resistance in the drift region, a body diode, and two first resistors (I and II); modeling the resistance in the drift region of the superjunction MOSFET device based on its physical structural parameters, using a linear approximation to obtain the linear variable resistance model; and introducing a Taylor polynomial to describe the self-heating first resistor model. The model parameters of this invention are used to obtain the parameters of the conventional MOSFET model, the body diode model, and the self-heating first resistor model using measured data from the device. The linear variable resistance model and modeling method for the drift region provided by this invention can effectively simulate the characteristics of a superjunction MOSFET device in various operating regions, achieving high simulation accuracy.

Description

Technical Field

[0001] This invention relates to the field of semiconductor device simulation, specifically to a linear variable resistance model and modeling method for the drift region of a superjunction MOSFET device. Background Technology

[0002] In recent years, thanks to the rapid development of computer technology, circuit simulation has become increasingly familiar and utilized, gradually becoming an indispensable key step in circuit design. SPICE (Simulation Program for Integrated Circuits Emphasis) was developed in 1975 by the Electronics Research Laboratory at the University of California, Berkeley. Integrated circuit design, PCB-level design, and system-level design all rely on SPICE simulation. Device models are seen as a bridge connecting circuit design and manufacturing processes. With the help of circuit simulators, device models can be used to conduct numerous virtual experiments and simulations to predict circuit performance, thereby improving design efficiency and reducing design costs.

[0003] The accuracy of device models directly affects the results of circuit behavior simulation and performance evaluation. However, traditional MOSFET models are designed for low-power MOS devices with lateral structures and cannot accurately describe the characteristics of power superjunction MOSFET devices. When superjunction MOSFET devices are applied to circuit design, the simulation results deviate significantly. Therefore, one or more methods are needed to solve the above problems. Summary of the Invention

[0004] This invention addresses the problem that traditional MOSFET models cannot accurately describe the characteristics of superjunction MOSFET devices. On one hand, it provides a modeling method for superjunction MOSFET devices; on the other hand, it provides a linear variable resistance model for the drift region of superjunction MOSFET devices. The specific technical solutions are as follows:

[0005] A method for modeling the linear variable resistance of the drift region in a superjunction MOSFET device includes the following steps:

[0006] (1) Construct the superjunction MOSFET circuit model topology;

[0007] (2) The drift region of the superjunction MOSFET is modeled for resistance, and a linear approximation is used to obtain a linear variable resistance model of the drift region; Taylor polynomials are introduced to describe the first resistance model of the device self-heating effect.

[0008] (3) Obtain the drift region linear variable resistance model parameters through the physical structure parameters of the superjunction MOSFET device, and obtain the MOSFET model parameters, body diode model parameters and self-heating first resistance model parameters through the measured data of the device.

[0009] As a preferred method, the linear variable resistor model in the drift region in step (2) is derived by calculation using physical formulas, and the derivation method is as follows:

[0010] Because the resistance of the JFET region also changes with the drain voltage, the superjunction structure will be simplified during model building to ensure model continuity. When the superjunction MOSFET is normally turned on, the device resistance is mainly composed of the channel resistance R. ch JFET resistor R JFET and the resistance R of the N-pillar drift region Drift It consists of three parts, with other resistors such as the source region resistance R. N+ Substrate resistance R sub And since the resistance of the metal is negligible, the total resistance R of the device when it is conducting is... on It can be represented as

[0011] R on =R ch +R JFET +R Drift

[0012] When the superjunction MOSFET is turned on, for any depth y in the drift region, the potential V(y) can be expressed by the voltage divider formula of the series resistor.

[0013]

[0014] In the formula, R(y) is the resistance value of the drift region from depth 0 to depth y, and V ds R is the drain-source voltage. ch R is the resistance in the channel region. varied Let R be the linear variable resistance in the drift region. When the gate voltage is near the threshold voltage, the change in variable resistance is negligible compared to the channel resistance, and the variable resistance can be considered a constant R0. However, when the gate voltage increases to the point where scattering at the channel carrier surface is dominant, the channel resistance relative to the variable resistance in the drift region can be considered zero as the drain voltage increases. Therefore, the potential at height y is...

[0015]

[0016] Considering the charge balance of PN pillars, when the width of the PN pillars is the same, the doping concentration N of the P pillars is... P Equal to the doping concentration N of the N-pillar N At this point, the depletion region width W of the PN column at the same height y is within the N column. DN (y) can be obtained

[0017]

[0018] In the formula, N DriftV represents the doping concentration in the drift region, and its magnitude corresponds to the doping concentration of the P and N pillars. bi ε is the built-in potential of the PN junction. si Let ρ be the dielectric constant of silicon, q be the charge, and for the entire cell, the total width of the depletion region at a depth y in the N-pillar is 2W. DN (y), then the width W of the current at that depth. i (y) is

[0019]

[0020] In the formula, W cell Given the cell width of the superjunction MOSFET, based on the above analysis, it's easy to see that the current path from the bottom to the top of the drift region is narrow to wide. Therefore, the shape of the N-pillar depletion line, i.e., the variable resistor in the drift region, can be considered as a straight line. The variable resistor in the drift region is similar in shape to a trapezoid. The above formula can be used to calculate the current width W at the lower base of the trapezoid, i.e., at height H. bot for

[0021]

[0022] Similarly, the width W of the current at the upper base of the trapezoid, i.e., the point where the height is 0, can be obtained. top for

[0023]

[0024] Therefore, the resistance dR(y) at depth y can be expressed as:

[0025]

[0026] In the formula, Z is the length of the superjunction MOSFET cell along the vertical direction, μ n Let H be the electron mobility and H be the thickness of the epitaxial layer of the superjunction MOSFET; therefore, by integrating along the resistance dR(y) from 0 to y, the variable resistance R in the drift region can be obtained. varied The expression is

[0027]

[0028] As a preferred method, the measured data in step (3) includes: output characteristic curve, transfer characteristic curve and body diode current-voltage curve.

[0029] As a preferred method, simulation is performed using the SPICE simulation circuit simulator.

[0030] On the other hand, the present invention also provides a linear variable resistance model for the drift region of a superjunction MOSFET device, comprising:

[0031] MOSFET1, drift region linear variable resistor2, body diode3, first resistor I41, and first resistor II42;

[0032] Based on the carrier movement characteristics between the source, gate, source region, and well region of a superjunction MOSFET device, the source, gate, source region, and well region are equivalent to MOSFET1; based on the carrier movement characteristics between the JFET region and N-pillar of a superjunction MOSFET device, the JFET region and N-pillar are equivalent to the drift region linear variable resistor 2 connected in parallel with the first resistor I41; the substrate of the superjunction MOSFET device is equivalent to the first resistor II42; based on the carrier movement characteristics between the well region, P-pillar, and N-pillar of a superjunction MOSFET device, the well region, P-pillar, and N-pillar regions are equivalent to body diode 3;

[0033] The drain 12 of the MOSFET is connected to the first end of the drift region linear variable resistor 2; the source 11 of the MOSFET is connected to the positive terminal of the body diode 3; the first end of the first resistor I 41 is connected to the second end of the drift region linear variable resistor 2, the second end of the first resistor I 41 is connected to the first end of the first resistor II 42; the second end of the first resistor II 42 is connected to the negative terminal of the body diode 3.

[0034] MOSFET gate lead-out circuit model: gate 51; MOSFET source 11 lead-out circuit model: source 52; body diode 3 negative lead-out circuit model: drain 53.

[0035] As a preferred embodiment, the first resistor I41 is a voltage-controlled resistor; the first resistor II42 is a fixed resistor. The first resistor I(41) and the first resistor II42 are equivalent to the first resistor, which is actually a temperature-controlled resistor.

[0036] The beneficial effects of this invention are as follows: This invention provides a linear variable resistance model and modeling method for the drift region of a superjunction MOSFET device. It simulates the structure of the superjunction MOSFET device as an equivalent simulation, which can effectively simulate the characteristics of the superjunction MOSFET device in each working region. The simulation accuracy is high, it can fit the measured data of the superjunction MOSFET well, and it is applicable to all superjunction MOSFET devices. Attached Figure Description

[0037] Figure 1 This is a flowchart of the simulation method for the superjunction MOSFET device of the present invention.

[0038] Figure 2 This is a schematic diagram of the cell structure of the superjunction MOSFET device of the present invention.

[0039] Figure 3 This is a schematic diagram of the circuit model structure of the superjunction MOSFET device of the present invention.

[0040] Appendix Figure 2 Notation: P represents the P-pillar of the superjunction MOSFET, N represents the N-pillar of the superjunction MOSFET, P+ represents the ohmic contact region of the superjunction MOSFET, N+ represents the source region of the superjunction MOSFET, P-body represents the body region of the superjunction MOSFET, N+sub represents the substrate of the superjunction MOSFET, W... i (y) represents the width of the current at height y, Gate represents the superjunction gate, Source represents the superjunction source, and Drain represents the superjunction drain.

[0041] Appendix Figure 3 Labels: 1 for MOSFET; 11 for MOSFET source; 12 for MOSFET drain; 2 for drift region linear variable resistor; 3 for body diode; 41 for first resistor I; 42 for first resistor II; 51 for circuit model gate; 52 for circuit model source; 53 for circuit model drain. Detailed Implementation

[0042] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0043] Example 1

[0044] This embodiment provides a method for modeling the linear variable resistance in the drift region of a superjunction MOSFET device, including the following steps:

[0045] (1) Construct the superjunction MOSFET circuit model topology;

[0046] (2) The drift region of the superjunction MOSFET is modeled for resistance, and a linear approximation is used to obtain a linear variable resistance model of the drift region; Taylor polynomials are introduced to describe the first resistance model of the device self-heating effect.

[0047] (3) Obtain the drift region linear variable resistance model parameters through the physical structure parameters of the superjunction MOSFET device, and obtain the MOSFET model parameters, body diode model parameters and self-heating first resistance model parameters through the measured data of the device.

[0048] Example 2

[0049] This embodiment provides a linear variable resistance model for the drift region of a superjunction MOSFET device, including:

[0050] MOSFET1, drift region linear variable resistor2, body diode3, first resistor I41, and first resistor II42;

[0051] Based on the carrier movement characteristics between the source, gate, source region, and well region of a superjunction MOSFET device, the source, gate, source region, and well region are equivalent to MOSFET1; based on the carrier movement characteristics between the JFET region and N-pillar of a superjunction MOSFET device, the JFET region and N-pillar are equivalent to the drift region linear variable resistor 2 connected in parallel with the first resistor I41; the substrate of the superjunction MOSFET device is equivalent to the first resistor II42; based on the carrier movement characteristics between the well region, P-pillar, and N-pillar of a superjunction MOSFET device, the well region, P-pillar, and N-pillar regions are equivalent to body diode 3;

[0052] The drain 12 of the MOSFET is connected to the first end of the drift region linear variable resistor 2; the source 11 of the MOSFET is connected to the positive terminal of the body diode 3; the first end of the first resistor I 41 is connected to the second end of the drift region linear variable resistor 2, the second end of the first resistor I 41 is connected to the first end of the first resistor II 42; the second end of the first resistor II 42 is connected to the negative terminal of the body diode 3.

[0053] MOSFET gate lead-out circuit model: gate 51; MOSFET source 11 lead-out circuit model: source 52; body diode 3 negative lead-out circuit model: drain 53.

[0054] The first resistor, I41, is a voltage-controlled resistor; the first resistor, II42, is a fixed resistor. The whole is equivalent to the first resistor, which is actually a temperature-controlled resistor.

[0055] Example 3

[0056] In this example embodiment, a modeling method for a superjunction MOSFET device is provided; refer to Figure 1 As shown, the specific steps include:

[0057] S1. Construct the superjunction MOSFET circuit model topology, wherein the superjunction MOSFET circuit model includes MOSFET1, drift region linear variable resistor2, body diode3, and first resistor I41 and first resistor II42;

[0058] Based on the carrier movement characteristics between the source, gate, source region, and well region of a superjunction MOSFET device, the source, gate, source region, and well region are equivalent to MOSFET1; based on the carrier movement characteristics between the JFET region and N-pillar of a superjunction MOSFET device, the JFET region and N-pillar are equivalent to the drift region linear variable resistor 2 connected in parallel with the first resistor I41; the substrate of the superjunction MOSFET device is equivalent to the first resistor II42; based on the carrier movement characteristics between the well region, P-pillar, and N-pillar of a superjunction MOSFET device, the well region, P-pillar, and N-pillar regions are equivalent to body diode 3;

[0059] The drain 12 of the MOSFET is connected to the first end of the drift region linear variable resistor 2; the source 11 of the MOSFET is connected to the positive terminal of the body diode 3; the first end of the first resistor I 41 is connected to the second end of the drift region linear variable resistor 2, the second end of the first resistor I 41 is connected to the first end of the first resistor II 42; the second end of the first resistor II 42 is connected to the negative terminal of the body diode 3.

[0060] MOSFET gate lead-out circuit model: gate 51; MOSFET source 11 lead-out circuit model: source 52; body diode 3 negative lead-out circuit model: drain 53.

[0061] S2. Resistance modeling is performed on the JFET region and drift region of the superjunction MOSFET. A linear approximation is used to obtain a linearly variable resistance model for the drift region. Taylor polynomials are introduced to describe the first resistance model of the device's self-heating effect. The linearly variable resistance model for the drift region is derived through physical formulas, as follows:

[0062] Because the resistance of the JFET region also changes with the drain voltage, the superjunction structure will be simplified during model building to ensure model continuity. When the superjunction MOSFET is normally turned on, the device resistance is mainly composed of the channel resistance R. ch JFET resistor R JFET and the resistance R of the N-pillar drift region Drift It consists of three parts, with other resistors such as the source region resistance R. N+ Substrate resistance R sub And since the resistance of the metal is negligible, the total resistance R of the device when it is conducting is... on It can be represented as

[0063] R on =R ch +R JFET +R Drift

[0064] When the superjunction MOSFET is turned on, for any depth y in the drift region, the potential V(y) can be expressed by the voltage divider formula of the series resistor.

[0065]

[0066] In the formula, R(y) is the resistance value of the drift region from depth 0 to depth y, and V ds R is the drain-source voltage. ch R is the resistance in the channel region. varied Let R0 be the linear variable resistance in the drift region. When the gate voltage is near the threshold voltage, the change in variable resistance is negligible relative to the channel resistance, and the variable resistance can be considered a constant R0. However, when the gate voltage increases to the point where scattering at the channel carrier surface is dominant, the channel resistance relative to the variable resistance in the drift region can be considered zero as the drain voltage increases. Therefore, the potential at height y is...

[0067]

[0068] Considering the charge balance of PN pillars, when the width of the PN pillars is the same, the doping concentration N of the P pillars is... P Equal to the doping concentration N of the N-pillar N At this point, the width of the depletion region of the PN column at the same height y within the N column can be calculated.

[0069]

[0070] In the formula, N Drift V represents the doping concentration in the drift region, and its magnitude corresponds to the doping concentration of the P and N pillars. bi ε is the built-in potential of the PN junction. si Let be the dielectric constant of silicon, and q be the charge. For the entire cell, the total width of the depletion region at a depth of y in the N-pillar is 2W. DN (y), then the width W of the current at that depth. i (y) is

[0071]

[0072] In the formula, W cell Let H be the cell width of the superjunction MOSFET. From the above analysis, it's easy to see that the current path from the bottom to the top of the drift region is narrow to wide. Therefore, the N-pillar depletion line, i.e., the shape of the left and right sides of the drift region variable resistor, can be considered as straight lines. The shape of the drift region variable resistor is similar to a trapezoid. The above formula can be used to calculate the current width W at the lower base of the trapezoid, i.e., at height H. bot for

[0073]

[0074] Similarly, the width W of the current at the upper base of the trapezoid, i.e., the point where the height is 0, can be obtained. top for

[0075]

[0076] Therefore, the resistance dR(y) at depth y can be expressed as:

[0077]

[0078] In the formula, Z is the length of the superjunction MOSFET cell along the vertical direction, μ n Let H be the electron mobility and H be the thickness of the epitaxial layer of the superjunction MOSFET. Therefore, by integrating the resistance dR(y) from 0 to y, the variable resistance R in the drift region can be obtained. varied The expression is

[0079]

[0080] Due to the self-heating effect of superjunction MOSFET devices: when the gate and drain voltages of a superjunction MOSFET device are so large that the power consumption generated by the operating current cannot be dissipated in time, the temperature of the superjunction MOSFET device will rise. Temperature has a significant impact on superjunction MOSFET devices, which will reduce the carrier mobility in the drift region. As a result, the drift region resistance of the superjunction MOSFET device during forward conduction will increase with the increase of temperature. This resistance is related to the gate and drain voltages of the superjunction MOSFET device. Therefore, the first resistance model I41 is used to represent the resistance of the superjunction MOSFET device. The first resistance model I41 is a voltage-controlled resistor model. The voltage-controlled resistor model is established by fitting the Taylor polynomial.

[0081] S3. Obtain the drift region linear variable resistance model parameters through the physical structure parameters of the superjunction MOSFET device. Obtain the MOSFET model parameters, body diode model parameters, and self-heating first resistor model parameters through measured data of the device. Determine the model parameter K in the MOSFET model based on the output characteristic curve of the linear region of the superjunction MOSFET device. p V th K p V is the intrinsic conductivity factor for the MOSFET model. th This represents the threshold voltage of the MOSFET model.

[0082] When the gate voltage of a superjunction MOSFET device satisfies the condition that the device is operating in the saturation region, the channel resistance of the superjunction MOSFET device is very large, and the drift region resistance is relatively negligible. In this case, MOSFET Model 1 dominates, and the following current-voltage model formulas apply.

[0083] I ds =K P / 2(V gs -V th )2

[0084] In the formula, I ds K is the drain-source current of MOSFET1. p V is the intrinsic conductivity factor of MOSFET1. gs V is the gate-source voltage of MOSFET1. th This is the threshold voltage of MOSFET1;

[0085] When the gate voltage of a superjunction MOSFET is high enough that the superjunction MOSFET will not experience a saturation region, as the drain voltage increases, the superjunction MOSFET will experience a quasi-saturation region. At this time, the channel resistance of the superjunction MOSFET is very small, and the drain voltage of the superjunction MOSFET is concentrated in the drift region. At this time, the linear variable resistance model 2 in the drift region dominates, and the parameters of the linear variable resistance model in the drift region are determined by the physical structure parameters of the superjunction MOSFET.

[0086] The model parameters in the Taylor polynomial of the first resistor model I are fitted based on the current and voltage data when the self-heating effect occurs; the parameters N and I of the body diode 3 are determined based on the source-drain forward bias current and voltage of the superjunction MOSFET device. S IK and the parasitic resistance of body diode 3; N is the emission coefficient of body diode 3, IS is the reverse saturation current of body diode 3, IK characterizes the current decay of body diode 3 under large injection conditions; the parasitic capacitance is R. S .

[0087] For body diode 3, the following current formula applies.

[0088]

[0089]

[0090] In the formula, I d For the body diode 3 current under large injection conditions, I d1 IK represents the current decay of the body diode 3 under conditions without large injection, and I represents the current decay of the body diode 3 under conditions with large injection. S For the reverse saturation current of body diode 3, V d V is the voltage across body diode 3, N is the emitter coefficient of body diode 3, and V T For thermal voltage, J S J is the reverse saturation current per unit area (bottom direction) of the body diode 3. SW Let PJ be the reverse saturation current per unit length (circumferential direction) of body diode 3. Area and PJ are the junction area and length of body diode 3, respectively.

[0091] The model parameters N and I in the body diode 3 above are determined based on the source-drain forward bias current-voltage curves of the superjunction MOSFET device. S The parasitic resistance R of IK and body diode 3 S The specific extraction method involves comparing the model simulation curve with the measured curve, and continuously adjusting the three parameters of the body diode mentioned above, so that the model simulation curve and the measured curve can perfectly fit each other.

[0092] In this example embodiment, the SPICE simulator is used to simulate a superjunction MOSFET device.

[0093] This example provides a linear variable resistance model and modeling method for the drift region of a superjunction MOSFET device. It simulates the superjunction MOSFET device from a structural perspective, effectively simulating the characteristics of the superjunction MOSFET device in each operating region. The simulation is highly accurate, fits the measured data of the superjunction MOSFET well, and is applicable to all superjunction MOSFET devices.

[0094] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A method of modeling the drift region of a super junction MOSFET device as a linear variable resistor, the method comprising: Includes the following steps: (1) Construct the superjunction MOSFET circuit model topology; (2) The drift region of the superjunction MOSFET is modeled for resistance, and a linear approximation is used to obtain a linear variable resistance model of the drift region; Taylor polynomials are introduced to describe the first resistance model of the device self-heating effect. (3) Obtain the drift region linear variable resistance model parameters through the physical structure parameters of the superjunction MOSFET device, and obtain the MOSFET model parameters, body diode model parameters and self-heating first resistance model parameters through the measured data of the device. The linear variable resistor model in the drift region in step (2) is derived through calculation using physical formulas, and the derivation method is as follows: Because the resistance of the JFET region also changes with the drain voltage, the superjunction structure will be simplified during model building to ensure model continuity. When the superjunction MOSFET is normally turned on, the device resistance is determined by the channel resistance R. ch JFET resistor R JFET and the resistance R of the N-pillar drift region Drift It consists of three parts, with source region resistance R. N+ Substrate resistance R sub And since the resistance of the metal is negligible, the total resistance R of the device when it is conducting is... on It can be represented as , When the superjunction MOSFET is turned on, for any depth y in the drift region, the potential V(y) can be expressed by the voltage divider formula of the series resistor. ， In the formula, R(y) is the resistance value of the drift region from depth 0 to depth y, and V ds R is the drain-source voltage. ch R is the resistance in the channel region. varied Let R0 be the linear variable resistance in the drift region. When the gate voltage is near the threshold voltage, the change in variable resistance is negligible compared to the channel resistance, and the variable resistance can be considered a constant R0. However, when the gate voltage increases to the point where scattering at the channel carrier surface is dominant, the channel resistance relative to the variable resistance in the drift region can be considered zero as the drain voltage increases. Therefore, the potential at height y is... ， Considering the charge balance of PN pillars, when the width of the PN pillars is the same, the doping concentration N of the P pillars is... P Equal to the doping concentration N of the N-pillar N At this point, the depletion region width W of the PN column at the same height y is within the N column. DN (y) can be obtained In the formula, N Drift V represents the doping concentration in the drift region, and its magnitude corresponds to the doping concentration of the P and N pillars. bi ε is the built-in potential of the PN junction. si Let ρ be the dielectric constant of silicon, q be the charge, and for the entire cell, the total width of the depletion region at a depth y in the N-pillar is 2W. DN (y), then the width W of the current at that depth. i (y) is ， In the formula, W cell Given the cell width of a superjunction MOSFET, the current path from the bottom to the top of the drift region is narrow to wide. Therefore, the N-pillar depletion line, i.e., the shape of the left and right sides of the drift region variable resistor, can be considered as a straight line. The shape of the drift region variable resistor is similar to a trapezoid. The above formula can be used to calculate the current width W at the lower base of the trapezoid, i.e., at a height of H. bot for ， Similarly, the width W of the current at the upper base of the trapezoid, i.e. at the height of 0, can be obtained top For ， Therefore, the resistance dR(y) at depth y can be expressed as: ， where Z is the length of the super-junction MOSFET cell along the vertical direction, μ n is the electron mobility, H is the thickness of the super-junction MOSFET epitaxial layer; thus, by integrating the resistance dR(y) from 0 to y, the expression for the drift region variable resistance R varied is obtained 。 2. The method of claim 1, wherein the linear variable resistor modeling of the drift region of the super junction MOSFET device is performed by: The measured data in step (3) include: output characteristic curve, transfer characteristic curve and body diode current-voltage curve.

3. The method for modeling the linear variable resistance of the drift region of a superjunction MOSFET device according to claim 1, characterized in that, Simulation was performed using the SPICE simulation circuit simulator.

4. The super junction MOSFET device drift region linear variable resistor model obtained by the method of any one of claims 1 to 3, characterized in that, include: MOSFET (1), drift region linear variable resistor (2), body diode (3), first resistor I (41), first resistor II (42); Based on the carrier movement characteristics between the source, gate, source region, and well region of the superjunction MOSFET device, the source, gate, source region, and well region are equivalent to MOSFET (1); based on the carrier movement characteristics between the JFET region and N-pillar of the superjunction MOSFET device, the JFET region and N-pillar are equivalent to the drift region linear variable resistor (2) connected in parallel with the first resistor I (41); the substrate of the superjunction MOSFET device is equivalent to the first resistor II (42); based on the carrier movement characteristics between the well region, P-pillar, and N-pillar of the superjunction MOSFET device, the well region, P-pillar, and N-pillar regions are equivalent to body diode (3). The drain (12) of the MOSFET is connected to the first end of the drift region linear variable resistor (2); the source (11) of the MOSFET is connected to the positive terminal of the body diode (3); the first end of the first resistor I (41) is connected to the second end of the drift region linear variable resistor (2), the second end of the first resistor I (41) is connected to the first end of the first resistor II (42); the second end of the first resistor II (42) is connected to the negative terminal of the body diode (3); MOSFET gate lead-out circuit model gate (51), MOSFET source (11) lead-out circuit model source (52), body diode (3) negative lead-out circuit model drain (53).

5. The linearly variable resistor model for the super junction MOSFET device of claim 4, wherein, The first resistor I (41) is a voltage-controlled resistor; the first resistor II (42) is a fixed resistor. The first resistor I (41) and the first resistor II (42) are equivalent to the first resistor, which is actually a temperature-controlled resistor.

Images