Modeling and application method of nonlinear capacitance model of DSRD device

Abstract

The invention relates to a modeling and application method of a nonlinear capacitance model of a DSRD device, and the modeling method comprises the following steps: splitting a nonlinear capacitor, and building a current expression of the nonlinear capacitor of the DSRD device; according to the current expression of the nonlinear capacitor of the DSRD device and the working principle of the DSRD device, constructing a nonlinear capacitor to-be-fitted model of the DSRD device; and according to the optimal model CV curve, updating to-be-fitted parameters in the nonlinear capacitance to-be-fitted model of the DSRD device to obtain the nonlinear capacitance model of the DSRD device. According to the nonlinear capacitance model of the DSRD device established by the modeling method of the nonlinear capacitance model of the DSRD device provided by the invention, accurate fitting of the nonlinear capacitance of the DSRD device in a full voltage range can be realized, and accurate simulation of pulse rise time can be realized.

Description

Technical Field

[0001] The invention belongs to the technical field of semiconductor simulation, and in particular relates to a modeling and application method of a nonlinear capacitance model of a DSRD device. Background Art

[0002] In recent years, ultrafast high pulse power technology has been widely used in food processing, medical treatment, water treatment, waste gas treatment, ozone generation and ion implantation. The switch is a key part of pulse power technology, and its characteristic parameters have a direct impact on the rise time, amplitude and turn-off time of the output pulse. SiC drift step recovery diode (DSRD) is a high-power ultrafast semiconductor switch that can output nanosecond instantaneous narrow pulse signals due to its advantages such as fast switching speed, high repetition frequency and stackability.

[0003] In 1975, the University of California, Berkeley, developed the SPICE (Simulation Program for Integrated Circuits Emphasis) program. With the development of computer technology, SPICE gradually evolved into PSpice software. With the help of this circuit software, users can conduct a large number of circuit simulation experiments to predict the performance of the circuit. The device model is a bridge between circuit design and process production. The accuracy of the device model directly affects the simulation results of the circuit. In order to make the simulation results closer to the actual results, an accurate device model must be established to improve design efficiency and reduce design costs.

[0004] The existing DSRD circuit model mainly uses 1N4007 diodes to equal the PN structure of DSRD, multi-stage series connection to equal the multi-layer stack of PN junctions, and fixed parallel capacitors to equal the capacitance effect of the PN junction of DSRD devices. However, the pulse rise time obtained by the above model simulation is inconsistent with the actual measurement, and the accuracy of the simulation results is difficult to ensure. Summary of the invention

[0005] In order to solve the above problems existing in the prior art, the present invention provides a SPICE modeling method for a DSRD device. The technical problem to be solved by the present invention is achieved by the following technical solutions:

[0006] A first aspect of the present invention provides a SPICE modeling method for a DSRD device, comprising the following steps:

[0007] Obtain the measured CV curve of the DSRD device;

[0008] The nonlinear capacitor is split and the current expression of the nonlinear capacitor of the DSRD device is established;

[0009] According to the current expression of the nonlinear capacitance of the DSRD device and the working principle of the DSRD device, a nonlinear capacitance model to be fitted of the DSRD device is constructed;

[0010] Changing the model parameters of the nonlinear capacitance to be fitted model of the DSRD device, and simulating to obtain several model CV curves;

[0011] Fitting the measured CV curve and the several model CV curves in mathematical software, and obtaining the best model CV curve among the several model CV curves according to the fitting result;

[0012] The parameters to be fitted in the nonlinear capacitance to be fitted model of the DSRD device are updated according to the optimal model CV curve to obtain the nonlinear capacitance model of the DSRD device.

[0013] In one achievable manner, the operating principle of the DSRD device includes: forward injection, reverse extraction and fast shutdown.

[0014] In one achievable manner, the current expression of the nonlinear capacitance of the DSRD device is:

[0015]

[0016] Wherein, i is the current of the nonlinear capacitor of the DSRD device, f(U) is the function of the nonlinear capacitor changing with the voltage U at both ends, represents differential, f(V) is a nonlinear function, and C0 is a linear capacitor.

[0017] In an achievable manner, the nonlinear capacitance model to be fitted of the DSRD device includes: a voltage-controlled current source G s , voltage source V S3 , resistor R S , voltage-controlled voltage source E3, voltage source V S4 and linear capacitance C0, where

[0018] The voltage-controlled current source G s , the voltage source V S3 and the resistor R S Connect in series to form the first circuit;

[0019] The voltage-controlled voltage source E3, the voltage source V S4 Connected in series with the linear capacitor C0 to form a second loop;

[0020] The first loop and the second loop are both grounded.

[0021] In one achievable manner, the voltage-controlled current source G sThe control voltage is the voltage across the DSRD device, and the voltage-controlled current source G s The output current is the nonlinear function f(V);

[0022] The voltage source V S3 and the voltage source V S4 The voltage value is 0;

[0023] The output voltage and input voltage of the voltage-controlled voltage source E3 are both the voltages at both ends of the DSRD device;

[0024] The resistor R S It is used to ensure the convergence of the nonlinear capacitance model of the DSRD device during the simulation process.

[0025] In one achievable manner, the current I1 of the first loop = f (V);

[0026] The current of the second circuit

[0027] In one implementable manner, the model parameter is a linear capacitance C0;

[0028] The parameters to be fitted are the linear capacitance C0 and the nonlinear function f(V).

[0029] In one implementable manner, the unit of the linear capacitance C0 is the same as the unit of the capacitance in the measured CV curve of the DSRD device.

[0030] A second aspect of the present invention provides an application method of a nonlinear capacitance model of a DSRD device, comprising the following steps:

[0031] According to the nonlinear capacitance model of the DSRD device, the nonlinear capacitance equivalent current source G of the DSRD device is obtained. c The nonlinear capacitance model of the DSRD device is established according to the modeling method of the nonlinear capacitance model of the DSRD device provided by the first aspect of the present invention;

[0032] Based on the nonlinear capacitor equivalent current source G c Construct an equivalent circuit model of the DSRD device.

[0033] In an achievable manner, the equivalent circuit model of the DSRD device includes: a resistor R, an inductor L, a diode D1, a diode D2, a diode D3 and a nonlinear capacitor equivalent current source G c ,in,

[0034] One end of the resistor R serves as the cathode of the equivalent circuit model, and the other end is connected to the cathode of the diode D1 through the inductor L;

[0035] The anode of the diode D1 is connected to the cathode of the diode D2;

[0036] The anode of the diode D2 is connected to the cathode of the diode D3;

[0037] The anode of the diode D3 serves as the anode of the equivalent circuit model;

[0038] The nonlinear capacitor equivalent current source G c connected between the anode of the diode D3 and the cathode of the diode D1;

[0039] The nonlinear capacitor equivalent current source G c The value of is the product of the current I1 of the first loop and the current I2 of the second loop in the nonlinear capacitance model of the DSRD device.

[0040] Compared with the prior art, the present invention has the following beneficial effects:

[0041] The modeling method of the nonlinear capacitance model of the DSRD device of the present invention establishes a current expression of the nonlinear capacitance of the DSRD device by splitting the nonlinear capacitance, and constructs a nonlinear capacitance model to be fitted of the DSRD device according to the current expression of the nonlinear capacitance of the DSRD device and the working principle of the DSRD device, and obtains the nonlinear capacitance model of the DSRD device by updating the parameters to be fitted in the nonlinear capacitance model to be fitted. The nonlinear capacitance model of the DSRD device established by the modeling method of the nonlinear capacitance model of the DSRD device provided by the present invention can realize accurate fitting of the DSRD nonlinear capacitance within the full voltage range, can be applied to DSRD devices of different structures and areas, has few model parameters, is easy to adjust, and reduces the complexity of parameter extraction, and can realize accurate simulation of pulse rise time through the nonlinear capacitance model of the DSRD device. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 It is a schematic diagram of the structure of the DSRD device;

[0043] Figure 2 It is a flow chart of the steps of a method for modeling a nonlinear capacitance model of a DSRD device provided by an embodiment of the present invention;

[0044] Figure 3 is a measured CV curve diagram of the DSRD device provided in an embodiment of the present invention;

[0045] Figure 4 It is a schematic diagram of the circuit structure of the nonlinear capacitance to be fitted model of the DSRD device provided in an embodiment of the present invention;

[0046] Figure 5The embodiment of the present invention provides the best model CV curve diagram;

[0047] Figure 6 is a circuit structure diagram of an equivalent circuit model of a DSRD device provided in an embodiment of the present invention;

[0048] Figure 7 is a circuit structure diagram of a pulse generating circuit provided in an embodiment of the present invention;

[0049] Figure 8 It is a simulation result diagram provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0050] The present invention is further described in detail below with reference to specific embodiments, but the embodiments of the present invention are not limited thereto.

[0051] See also Figure 1 , Figure 1 It is a schematic diagram of the structure of the DSRD device. The DSRD device includes a cathode (Cathode), an N-type heavily doped region (N+), a lightly doped P-type base region (P-base), a P-type heavily doped region (P+), and an anode (Anode) arranged in sequence from bottom to top. The working principle of the DSRD device can be divided into three stages: forward injection, reverse extraction, and fast shutdown. In the forward injection stage, under the action of the forward pump current, electron-hole pairs are generated at the pn junction of the DSRD device and injected into the P-base to form plasma. In the reverse extraction stage, the reverse current extracts the plasma stored in the P-base. When the plasma extraction is completed, the reverse current of the DSRD reaches the maximum value, and then the balanced majority holes of the P-base are extracted, and the P-base space charge region expands at the saturation drift speed. In the fast shutdown stage, the P-base space charge region is fully established, the device is quickly shut down, and an ultrafast pulse is generated on the load. According to the working principle of the DSRD device, it can be seen that the DSRD is a strongly nonlinear semiconductor device, and its junction capacitance C during operation is j The voltage V across the device DSRD The increase first decreases rapidly and then decreases slowly, showing a strong nonlinearity. However, the parallel capacitor in the existing DSRD circuit model is difficult to accurately simulate the nonlinear capacitance of the DSRD device, resulting in low accuracy of the model simulation result. Therefore, this embodiment analyzes the working principle of the DSRD device and proposes a modeling method for the nonlinear capacitance model of the DSRD device to establish a model that can accurately simulate the nonlinear capacitance of the DSRD device.

[0052] See also Figure 2 , Figure 21 is a flow chart of the steps of a method for modeling a nonlinear capacitance model of a DSRD device provided by an embodiment of the present invention. The method for modeling a nonlinear capacitance model of a DSRD device provided by this embodiment comprises the following steps:

[0053] S1: Get the measured CV curve of the DSRD device.

[0054] Specifically, the junction capacitance C of the DSRD device is obtained by using the semiconductor power analyzer B1505A. j The data that changes with the voltage across the two ends is divided by the reference capacitance C j0 , and obtain the normalized capacitance C j / C j0 , construct the CV curve. Figure 3 As shown, Figure 3 is a measured CV curve diagram of the DSRD device provided in an embodiment of the present invention. In this embodiment, the reference capacitor C j0 =31pF, from Figure 3 It can be seen that the junction capacitance C of the DSRD device j As the voltage across the device V DSRD The increase first decreases rapidly and then decreases slowly, showing a strong nonlinearity.

[0055] S2: Decompose the nonlinear capacitor and establish the current expression of the nonlinear capacitor of the DSRD device.

[0056] Specifically, the characteristics of nonlinear capacitors are directly related to linear capacitors. The volt-ampere characteristics satisfied by linear capacitors are: When the capacitor is nonlinear, the expression of the nonlinear capacitance changing with the voltage U across the two ends is C = f(U), then the volt-ampere characteristic of the nonlinear capacitor is Decompose f(U) so that f(U) = C0 × f(V), where C0 is a linear capacitor and f(V) is a nonlinear function. The volt-ampere characteristic of the nonlinear capacitor can be expressed as Therefore, according to the relationship between nonlinear capacitance and linear capacitance, the nonlinear capacitance can be decomposed into the product of linear capacitance and nonlinear function, and the current expression of the nonlinear capacitance of the DSRD device is:

[0057]

[0058] Where i is the current of the nonlinear capacitor of the DSRD device, f(U) is the function of the nonlinear capacitance changing with the voltage U at both ends, represents differential, f(V) is a nonlinear function, and C0 is a linear capacitor.

[0059] S3: Based on the current expression of the nonlinear capacitance of the DSRD device and the working principle of the DSRD device, a nonlinear capacitance model to be fitted of the DSRD device is constructed.

[0060] Specifically, the working principle of the DSRD device includes: forward injection, reverse extraction and fast shutdown. Combining the working principle of the DSRD device and the current expression of the nonlinear capacitance of the DSRD device, the nonlinear function f(V) is realized by a voltage-controlled current source, and the differential process is realized by a linear capacitor. This embodiment designs a nonlinear capacitance model to be fitted of the DSRD device based on the working principle of the DSRD device in the three stages of forward injection, reverse extraction and fast shutdown, and simulates the working process of the DSRD device in the three stages in the form of a circuit, see Figure 4 , Figure 4 Schematic diagram of the circuit structure of the nonlinear capacitance model to be fitted of the DSRD device provided in the embodiment of the present invention. The nonlinear capacitance model to be fitted of the DSRD device provided in the embodiment of the present invention comprises: a voltage-controlled current source G s , voltage source V S3 , resistor R S , voltage-controlled voltage source E3, voltage source V S4 And linear capacitor C0. Among them, the voltage-controlled current source G s , voltage source V S3 and resistor R S The first circuit is connected in series, the voltage-controlled voltage source E3 and the voltage source V S4 The first loop and the second loop are connected in series with the linear capacitor C0 to form a second loop. Both the first loop and the second loop are grounded.

[0061] Specifically, the voltage-controlled current source G s The control voltage is the voltage across the DSRD device, and the voltage-controlled current source G s The output current is a nonlinear function f(V). The voltage source V S3 and voltage source V S4 The voltage values ​​of are all 0. The output voltage and input voltage of the voltage-controlled voltage source E3 are both the voltages at both ends of the DSRD device. S Used to ensure the convergence of the nonlinear capacitance equivalent model of the DSRD device during the simulation process.

[0062] In this embodiment, V S3 Used to detect the current of the first circuit. V S4 Used to detect the current in the second loop. s The output current of is a nonlinear function f(V), so the current I1 of the first loop = f(V). The output voltage and input voltage of the voltage-controlled voltage source E3 are both the voltages at both ends of the DSRD device, so the current of the second loop is Then the current of the DSRD device is Therefore, the nonlinear capacitance characteristics of the DSRD device can be expressed by the currents of the first loop and the second loop in the nonlinear capacitance to be fitted model of the DSRD device.

[0063] S4: changing the model parameters of the nonlinear capacitance model to be fitted of the DSRD device, and obtaining several model CV curves through simulation.

[0064] Specifically, the model parameter is the linear capacitor C0. The parameters to be fitted are the linear capacitor C0 and the nonlinear function f(V). The nonlinear capacitor to be fitted model of the DSRD device is used for simulation, and the value of the linear capacitor C0 is changed to obtain several model CV curves. The unit of the linear capacitor C0 is the same as the unit of the capacitance in the measured CV curve of the DSRD device. Exemplarily, the unit of Cj in the measured CV curve is pico-farad (pF), so the unit of the linear capacitor C0 is also pico-farad (pF).

[0065] S5: Fitting the measured CV curve and several model CV curves in the analysis software, and obtaining the best model CV curve among the several model CV curves according to the fitting results.

[0066] Specifically, in mathematical software such as MATLAB, the measured CV curve and several model CV curves are decomposed and fitted multiple times, and the model CV curve closest to the measured CV curve is selected from the several model CV curves as the best model CV curve. For example, an inverse proportional function is used for fitting, which is more consistent with the variation law of capacitance and has higher fitting accuracy. The best model CV curve obtained by fitting is as follows: Figure 5 shown.

[0067] S6: updating the parameters to be fitted in the nonlinear capacitance to be fitted model of the DSRD device according to the best model CV curve, and obtaining the nonlinear capacitance model of the DSRD device.

[0068] Specifically, according to the optimal model CV curve, the linear capacitance C0 and the nonlinear function f(V) in the nonlinear capacitance to be fitted model of the DSRD device are updated, and the updated nonlinear capacitance to be fitted model of the DSRD device is the nonlinear capacitance model of the DSRD device. Figure 5 The best model CV curve shown in the figure shows a linear capacitance C0 = 0.6pF and a nonlinear function f(V) = 18.2×V -0.4 According to the different DSRD devices being simulated, the model parameters (linear capacitance C0) in the nonlinear capacitance to be fitted model can be changed.

[0069] Furthermore, by writing PSpice language to implement the nonlinear capacitance model of the DSRD device obtained in step S6, a nonlinear capacitance SPICE subcircuit model module that can be directly called in the DSRD SPICE model can be obtained. When modeling DSRDs of different structures, only the corresponding parameters need to be adjusted. The specific PSpice language is as follows:

[0070] .subckt G c 9 20

[0071] .param c0=0.6pF,rs=1Ω

[0072] .func gg(x){PWR(x,0.4)}

[0073] gs 40 0value={18.2 / (gg(v(20,9)))}

[0074] vs3 40 41 0

[0075] rs 41 0{rs}

[0076] e3 42 0value={v(9,20)}

[0077] vs4 42 43 0

[0078] c0 43 0{c0}

[0079] gc 9 20value={i(vs4)*i(vs3)}.

[0080] Specifically, 0, 40, 41, 42, and 43 are Figure 4 The circuit nodes 9 and 20 in the nonlinear capacitance to be fitted model of the DSRD device shown are Figure 6 Circuit nodes in the equivalent circuit model of the DSRD device shown.

[0081] The model parameter of the nonlinear capacitance model of the DSRD device established by the modeling method provided in this embodiment is the linear capacitance C0. The model parameters are few, and the fitting difficulty can be reduced while the fitting accuracy can be improved, thereby improving the accuracy of the DSRD SPICE simulation. The SPICE codes for DSRD nonlinear capacitors of different structures and areas have a high degree of repeatability, forming a nonlinear capacitance subcircuit model that can be repeatedly called.

[0082] This embodiment also provides an application method of a nonlinear capacitance model of a DSRD device, comprising the following steps:

[0083] Step 1: According to the nonlinear capacitance model of the DSRD device, obtain the nonlinear capacitance equivalent current source G of the DSRD device c The nonlinear capacitance model of the DSRD device is established according to the modeling method of the nonlinear capacitance model of the DSRD device provided in this embodiment;

[0084] Step 2: Based on the nonlinear capacitor equivalent current source G c Construct an equivalent circuit model of the DSRD device.

[0085] like Figure 6 As shown, Figure 6 : is a circuit structure diagram of an equivalent circuit model of a DSRD device provided in an embodiment of the present invention. The equivalent circuit model of a DSRD device provided in this embodiment includes: a resistor R, an inductor L, a diode D1, a diode D2, a diode D3 and a nonlinear capacitor equivalent current source G c . Among them, one end of the resistor R serves as the cathode of the equivalent circuit model, and the other end is connected to the cathode of the diode D1 through the inductor L. The anode of the diode D1 is connected to the cathode of the diode D2. The anode of the diode D2 is connected to the cathode of the diode D3. The anode of the diode D3 serves as the anode of the equivalent circuit model. Nonlinear capacitor equivalent current source G c It is connected between the anode of diode D3 and the cathode of diode D1. Nonlinear capacitor equivalent current source G c The value of is the product of the current I1 of the first loop and the current I2 of the second loop in the nonlinear capacitance model of the DSRD device. Diodes D1, D2, and D3 are all 1N4007 diodes to simulate the multilayer PN structure of the DSRD. L is used to simulate the parasitic inductance of the device, which is generally within 10nH. Resistor R is used to simulate the resistance thermal effect when the DSRD is working, which is generally 1Ω.

[0086] The equivalent circuit model of the DSRD device obtained in this embodiment is substituted into the pulse generating circuit, and its dynamic characteristics are verified by simulation. Figure 7 As shown, Figure 7 : is a circuit structure diagram of a pulse generating circuit provided in an embodiment of the present invention, wherein the pulse generating circuit includes a MOS tube, a capacitor C1, a capacitor C2, a capacitor C3, an inductor L1, an inductor L1, an inductor L1, a resistor R L The equivalent circuit model of the DSRD device provided in this embodiment is connected to the pulse generating circuit in the form of a diode. The dynamic characteristics of the equivalent circuit model of the DSRD device are verified by simulating the pulse generating circuit. The simulation results are shown in FIG. Figure 8 As shown, the equivalent circuit model of the DSRD device provided in this embodiment can predict the rise time of the pulse very accurately.

[0087] The modeling method of the nonlinear capacitance model of the DSRD device provided in the present embodiment establishes a current expression of the nonlinear capacitance of the DSRD device by splitting the nonlinear capacitance, and constructs a nonlinear capacitance model to be fitted of the DSRD device according to the current expression of the nonlinear capacitance of the DSRD device and the working principle of the DSRD device, and obtains the nonlinear capacitance model of the DSRD device by updating the parameters to be fitted in the nonlinear capacitance model to be fitted. The nonlinear capacitance model of the DSRD device established by the modeling method of the nonlinear capacitance model of the DSRD device provided in the present embodiment can realize accurate fitting of the DSRD nonlinear capacitance within the full voltage range, can be applied to DSRD devices of different structures and areas, has few model parameters, is easy to adjust, and reduces the complexity of parameter extraction, and can realize accurate simulation of pulse rise time through the nonlinear capacitance model of the DSRD device.

[0088] The above contents are further detailed descriptions of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.

Claims

1. A method for modeling a nonlinear capacitance model of a DSRD device, characterized in that: The following steps are involved: Obtain the measured CV curve of the DSRD device; The nonlinear capacitor is split and the current expression of the nonlinear capacitor of the DSRD device is established; According to the current expression of the nonlinear capacitance of the DSRD device and the working principle of the DSRD device, a nonlinear capacitance model to be fitted of the DSRD device is constructed; Changing the model parameters of the nonlinear capacitance to be fitted model of the DSRD device, and simulating to obtain several model CV curves; Fitting the measured CV curve and the several model CV curves in mathematical software, and obtaining the best model CV curve among the several model CV curves according to the fitting result; The parameters to be fitted in the nonlinear capacitance to be fitted model of the DSRD device are updated according to the optimal model CV curve to obtain the nonlinear capacitance model of the DSRD device.

2. The modeling method of a nonlinear capacitance model of a DSRD device according to claim 1, characterized in that: The working principle of the DSRD device includes: forward injection, reverse extraction and fast shutdown.

3. The modeling method of a nonlinear capacitance model of a DSRD device according to claim 2, characterized in that: The current expression of the nonlinear capacitance of the DSRD device is: Wherein, i is the current of the nonlinear capacitor of the DSRD device, f(U) is the function of the nonlinear capacitor changing with the voltage U at both ends, represents differential, f(V) is a nonlinear function, and C0 is a linear capacitor.

4. The method for modeling a nonlinear capacitance model of a DSRD device according to claim 3, characterized in that: The nonlinear capacitance model to be fitted of the DSRD device includes: a voltage-controlled current source G s , voltage source V S3 , resistor R S , voltage-controlled voltage source E3, voltage source V S4 and linear capacitance C0, where The voltage-controlled current source G s , the voltage source V S3 and the resistor R S Connect in series to form the first circuit; The voltage-controlled voltage source E3, the voltage source V S4 Connected in series with the linear capacitor C0 to form a second loop; The first loop and the second loop are both grounded.

5. The method for modeling a nonlinear capacitance model of a DSRD device according to claim 4, characterized in that: The voltage-controlled current source G s The control voltage is the voltage across the DSRD device, and the voltage-controlled current source G s The output current is the nonlinear function f(V); The voltage source V S3 and the voltage source V S4 The voltage value is 0; The output voltage and input voltage of the voltage-controlled voltage source E3 are both the voltages at both ends of the DSRD device; The resistor R S It is used to ensure the convergence of the nonlinear capacitance model of the DSRD device during the simulation process.

6. The modeling method of a nonlinear capacitance model of a DSRD device according to claim 5, characterized in that: The current I1 of the first loop = f (V); The current of the second circuit 7. The method for modeling a nonlinear capacitance model of a DSRD device according to claim 4, characterized in that: The model parameter is the linear capacitance C0; The parameters to be fitted are the linear capacitance C0 and the nonlinear function f(V).

8. The method for modeling a nonlinear capacitance model of a DSRD device according to claim 4, characterized in that: The unit of the linear capacitance C0 is the same as the unit of the capacitance in the measured CV curve of the DSRD device.

9. An application method of a nonlinear capacitance model of a DSRD device, characterized in that: The following steps are involved: According to the nonlinear capacitance model of the DSRD device, the nonlinear capacitance equivalent current source G of the DSRD device is obtained. c The nonlinear capacitance model of the DSRD device is established according to the modeling method of the nonlinear capacitance model of the DSRD device according to any one of claims 1 to 8; Based on the nonlinear capacitor equivalent current source G c Construct an equivalent circuit model of the DSRD device.

10. The application method of the nonlinear capacitance model of a DSRD device according to claim 9, characterized in that: The equivalent circuit model of the DSRD device includes: a resistor R, an inductor L, a diode D1, a diode D2, a diode D3 and a nonlinear capacitor equivalent current source G c ,in, One end of the resistor R serves as the cathode of the equivalent circuit model, and the other end is connected to the cathode of the diode D1 through the inductor L; The anode of the diode D1 is connected to the cathode of the diode D2; The anode of the diode D2 is connected to the cathode of the diode D3; The anode of the diode D3 serves as the anode of the equivalent circuit model; The nonlinear capacitor equivalent current source G c connected between the anode of the diode D3 and the cathode of the diode D1; The nonlinear capacitor equivalent current source G c The value of is the product of the current I1 of the first loop and the current I2 of the second loop in the nonlinear capacitance model of the DSRD device.

Images