Cascade PIN diode amplitude limiter electrothermal failure simulation method based on field-circuit cooperation

Abstract

The invention discloses a cascade PIN diode amplitude limiter electrothermal failure simulation method based on field-circuit collaboration, which comprises the following steps: converting a transmission line in a cascade PIN amplitude limiter into an equivalent lumped circuit element, and establishing a field-circuit collaboration simulation model of the amplitude limiter based on the lumped circuit element; obtaining a temperature dependence equation of the specific heat capacity and the heat conductivity, and correcting the heat conductivity and the physical model of the specific heat capacity of the amplitude limiter circuit based on the temperature dependence equation of the specific heat capacity and the heat conductivity; based on the field-circuit co-simulation model and the physical model, obtaining the distribution of a temperature field and an electric field in the amplitude limiter in combination with the thermal damage criterion of the amplitude limiter under the action of the high-power microwave pulse; and based on the temperature field and electric field distribution, obtaining the position of the thermal breakdown damage in the amplitude limiter.

Description

Technical Field

[0001] The invention belongs to the field of microwave circuits, and in particular relates to an electrothermal failure simulation method of a cascaded PIN diode limiter based on field-circuit synergy. Background Art

[0002] In the circuit model of the limiter, there are mainly equivalent lumped R, L, C simulation circuit models based on semiconductor PIN diode devices and field-circuit collaborative simulation models based on semiconductor devices. Using the equivalent lumped circuit model based on semiconductor devices, the simulation solution can only obtain the electrical response characteristics of the limiter during the pulse action process, and cannot obtain the multi-physical field distribution during the pulse action process in real time. In addition, the solution result is inaccurate and cannot reflect the actual response of the limiter during the pulse action. The current field-circuit simulation model of the limiter based on semiconductor PIN diode devices ignores the role of the transmission line in the limiter and cannot truly reflect the distribution of the electric field inside the device under the action of the signal. In addition, when conducting research and analysis on the failure mechanism of the limiter at high temperature, the current limiter model does not consider the temperature dependence of thermal parameters. Since thermal conductivity is closely related to the heat diffusion process inside the device, the solution result of the temperature equation is inaccurate.

[0003] In summary, the current limiter simulation circuit model cannot accurately solve the actual response process inside the limiter during the action of the pulse signal, that is, the actual distribution of the electric field and temperature field, and cannot effectively carry out research on the thermal damage and failure characteristics of the limiter. Summary of the invention

[0004] In order to solve the above technical problems, the present invention proposes an electrothermal failure simulation method of a cascaded PIN diode limiter based on field-circuit collaboration, which can realize the study of the thermal failure damage mechanism of the limiter during the pulse action of the limiter.

[0005] To achieve the above object, the present invention provides a method for simulating electrothermal failure of a cascaded PIN diode limiter based on field-circuit synergy, comprising:

[0006] The transmission line in the cascaded PIN limiter is converted into an equivalent lumped circuit element, and a field-circuit co-simulation model of the limiter is established based on the lumped circuit element;

[0007] Respectively obtaining a temperature dependence formula of the specific heat capacity of silicon and a temperature dependence equation of the thermal conductivity of silicon, and correcting the physical model of the thermal conductivity and specific heat capacity of the limiter circuit based on the temperature dependence formula of the specific heat capacity and the temperature dependence equation of the thermal conductivity;

[0008] Based on the field-circuit collaborative simulation model and the physical model, combined with the thermal damage criterion of the limiter under the action of high-power microwave pulses, the temperature field and electric field distribution inside the limiter are obtained;

[0009] Based on the temperature field and electric field distribution, the internal thermal breakdown damage position of the limiter is obtained.

[0010] Optionally, converting the quarter-wavelength transmission line in the cascaded PIN limiter into an equivalent lumped circuit element includes:

[0011] Divide the first wavelength transmission line into two second wavelength transmission lines of equal length, wherein the wavelength of the first wavelength transmission line is twice the wavelength of the second wavelength transmission line;

[0012] The two-port microwave networks of the two equal-length second wavelength transmission lines are converted into corresponding circuit elements.

[0013] Optionally, the method of converting the two-port microwave networks of the two equal-length one-eighth wavelength transmission lines into corresponding circuit elements is:

[0014] V1=I1Z 11 -I2Z 12

[0015] V2=I1Z 21 -I2Z 22

[0016] Where V1 and I1 are the voltage and current at the input port, respectively; V2 and I2 are the voltage and current at the output port, respectively; the negative sign indicates that the current at port 2 points to the outside; Z 11 and Z 22 are the voltage and current transfer coefficients respectively; Z 12 is the transfer impedance, Z 21 is the transfer admittance.

[0017] Optionally, the field-circuit collaborative simulation model of the limiter includes: a first-stage diode, two sections of second-wavelength transmission lines, a radio frequency choke inductor, and a second-stage diode;

[0018] Wherein, the first-stage diode, the second wavelength transmission line, the radio frequency choke inductor, the second wavelength transmission line and the second-stage diode are connected in sequence.

[0019] Optionally, the method for obtaining the temperature dependence equation of the specific heat capacity is:

[0020] χ = -3.22 × 10 -7 ×T 2 +0.004257×T-0.5020

[0021] Where χ is the thermal resistivity coefficient and T is the temperature.

[0022] Optionally, the method for obtaining the thermal conductivity temperature dependence equation is:

[0023] c L =1.063+0.002513×T-1.339×10 -6 ×T 2 +3.124×10 -10 ×T 3

[0024] Among them, c L is the thermal capacitance coefficient and T is the device temperature.

[0025] Optionally, the thermal damage criterion of the limiter under the action of the high-power microwave pulse is:

[0026] The maximum temperature of the internal components of the limiter reaching the melting point of the material under the action of high-power microwave pulse signal is taken as the failure criterion of thermal damage of the limiter.

[0027] Optionally, obtaining the internal thermal breakdown damage position of the limiter includes:

[0028] Based on the temperature field, determining a maximum temperature region inside the limiter;

[0029] When the maximum temperature of the maximum temperature area reaches the melting point, thermal breakdown occurs, and the thermal breakdown damage position is obtained.

[0030] Compared with the prior art, the present invention has the following advantages and technical effects:

[0031] The cascaded PIN limiter circuit of the present invention takes into account the impedance transformation function of the quarter-wavelength transmission line, and the circuit model can more accurately calculate the voltage amplitude distribution at the input and output ports of the limiter under the action of the external signal;

[0032] The limiter circuit model in the present invention modifies the thermal conductivity and specific heat capacity temperature model of silicon in the PIN diode. When conducting thermal failure research on the limiter, the influence of temperature field distribution at different positions of the device on thermal parameters is considered, especially in the high temperature area of ​​the device.

[0033] When the present invention studies the thermal damage of the limiter under the action of a high-power pulse, the temperature response at different internal positions can be accurately solved and the thermal failure area of ​​the limiter can be determined.

[0034] The present invention utilizes this model to perform device-circuit hybrid simulation and accurately obtain the limiting characteristic curve of the limiter;

[0035] The present invention uses this model to carry out research on thermal failure damage of the limiter under the action of high-power microwave pulses and determine the damage failure position of the limiter. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0037] Figure 1 It is a flow chart of an electrothermal failure simulation method of a cascaded PIN diode limiter based on field-circuit coordination according to an embodiment of the present invention;

[0038] Figure 2 1 is a schematic diagram of the structure of the cascaded PIN diode limiter according to an embodiment of the present invention; wherein, 1, a quarter-wavelength transmission line, 2, a PIN diode at the input end of the limiter, 3, a PIN diode at the output end of the limiter, 4, a radio frequency choke inductor, 5, a DC blocking capacitor at the input port, and 6, a DC blocking capacitor at the output port;

[0039] Figure 3 7 is a schematic diagram of an equivalent structure of a cascaded PIN diode limiter according to an embodiment of the present invention; wherein 7 is a first half one-eighth wavelength transmission line, and 8 is a second half one-eighth wavelength transmission line;

[0040] Figure 4 is a schematic diagram of a two-port microwave network of a one-eighth wavelength transmission line according to an embodiment of the present invention;

[0041] Figure 5 is a schematic diagram of an equivalent circuit model of a one-eighth wavelength transmission line according to an embodiment of the present invention;

[0042] Figure 6 It is a schematic diagram of a device-circuit hybrid simulation circuit of a cascaded PIN diode limiter according to an embodiment of the present invention;

[0043] Figure 7 is a schematic diagram of simulation results of a limiting characteristic curve of a limiter according to an embodiment of the present invention;

[0044] Figure 8 It is a schematic diagram of the spatial distribution of the temperature field inside the input-end PIN diode when the embodiment of the present invention fails due to thermal damage. DETAILED DESCRIPTION

[0045] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0046] It should be noted that the steps shown in the flowcharts of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and that, although a logical order is shown in the flowcharts, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0047] The present invention is mainly aimed at the shortcoming that the limiter simulation circuit model does not consider the effect of the transmission line. With the help of the transmission line equivalent theory, the microstrip transmission line in the limiter is converted into an equivalent circuit element, and a field-circuit collaborative simulation model of the limiter during the pulse action process is established. At the same time, in order to ensure the accuracy of the solution results of the limiter device temperature equation when conducting damage and failure research on the limiter under pulse action, a method for correcting the thermal parameter model of semiconductor materials is proposed. Finally, using this field-circuit collaborative simulation model of the limiter, the limiting characteristic curve of the limiter and the study of the thermal damage failure mechanism are simulated.

[0048] The present invention proposes a method for simulating the electrothermal failure of a cascaded PIN diode limiter based on field-circuit synergy. Figure 1 As shown, the specific steps include:

[0049] The transmission lines in the cascaded PIN limiter are converted into equivalent lumped circuit elements, and a field-circuit co-simulation model of the limiter is established based on the lumped circuit elements.

[0050] The temperature dependence square of the specific heat capacity of silicon and the temperature dependence equation of the thermal conductivity of silicon are obtained respectively, and the physical models of the thermal conductivity and the specific heat capacity of the limiter circuit are corrected based on the temperature dependence square of the specific heat capacity and the temperature dependence equation of the thermal conductivity;

[0051] Based on the field-circuit collaborative simulation model and the physical model, combined with the thermal damage criterion of the limiter under the action of high-power microwave pulses, the temperature field and electric field distribution inside the limiter are obtained;

[0052] Based on the temperature field and electric field distribution, the internal thermal breakdown damage position of the limiter is obtained.

[0053] Further, converting the transmission line in the cascaded PIN limiter into an equivalent lumped circuit element includes:

[0054] The first wavelength transmission line is divided into two second wavelength transmission lines of equal length, wherein the wavelength of the first wavelength transmission line is twice the wavelength of the second wavelength transmission line;

[0055] The two-port microwave network of two equal-length second wavelength transmission lines is converted into corresponding circuit elements.

[0056] Specifically, the present invention divides a quarter-wavelength transmission line into one-eighth-wavelength transmission lines of equal length at both ends according to the positions of the RF choke inductor and the two PIN diodes in the limiter circuit and the signal flow direction inside the structure when the signal acts on the limiter, and according to the position of the transmission line.

[0057] Specifically, the cascaded PIN limiter utilizes the "impedance transformation" function of the quarter-wavelength transmission line 1 to ensure that the PIN diodes at the input and output ports of the limiter have different voltage amplitudes.

[0058] According to the positions of two sections of one-eighth wavelength transmission lines, two PIN diodes and a radio frequency choke inductor, the present invention regards the cascaded PIN diode limiter circuit as a series circuit of five dual-port microwave networks.

[0059] In order to obtain the equivalent circuit of the limiter, the present invention needs to convert the two-port microwave network of two sections of one-eighth wavelength transmission line into corresponding circuit elements. The present invention calculates it according to the equivalent principle of the distributed parameter model to obtain the equivalent circuit of the two sections of transmission line.

[0060] Furthermore, the field-circuit collaborative simulation model of the limiter includes: a first-stage diode, two sections of one-eighth wavelength transmission lines, a radio frequency choke inductor, and a second-stage diode;

[0061] Wherein, the first-stage diode, the one-eighth wavelength transmission line, the radio frequency choke inductor, the one-eighth wavelength transmission line and the second-stage diode are connected in sequence.

[0062] Specifically, the invention connects the PIN diode, the RF choke inductor and the transmission line equivalent circuit together, and finally establishes a field-circuit collaborative simulation circuit of the cascaded PIN diode limiter. This circuit model can be used to perform multi-physics field hybrid simulation on the cascaded PIN diode limiter.

[0063] Specifically, the thermal damage failure of the limiter in the present invention is related to the temperature field distribution inside the limiter device under the action of high-power microwave pulse signals, and in the process of solving the temperature field of the device, the thermal conductivity and specific heat capacity of the material often play a non-negligible role. However, the thermal conductivity and specific heat capacity of semiconductor materials are functions of temperature and change with changes in temperature. In order to ensure the accuracy of the solution results of the internal temperature field of the cascaded PIN limiter device under the action of high-power microwave pulses, the invention proposes to correct the specific heat capacity and thermal conductivity model of the limiter material.

[0064] The material of the limiter in the present invention is silicon. The specific heat capacity and thermal conductivity values ​​of silicon under different temperature conditions are obtained through experimental testing. The temperature dependence equations of the specific heat capacity and thermal conductivity of silicon are obtained by fitting the test data, thereby correcting the thermal conductivity and specific heat capacity model of the limiter circuit.

[0065] Specifically, based on the temperature dependence square of specific heat capacity and the temperature dependence equation of thermal conductivity, the coefficients of different powers of temperature in the temperature equation are substituted into the solution parameter file of the material silicon, thereby correcting the physical model of thermal conductivity and specific heat capacity of the limiter circuit.

[0066] Furthermore, the thermal damage criterion of the limiter under the action of high-power microwave pulses is:

[0067] The maximum temperature of the internal components of the limiter reaching the melting point of the material under the action of high-power microwave pulse signal is taken as the failure criterion of thermal damage of the limiter.

[0068] Specifically, under the action of high-power microwave pulse signals, the maximum temperature of the local area inside the limiter structure of the invention often rises to the melting point of the material and melts, resulting in thermal breakdown damage and failure, causing permanent irreversible damage. Therefore, the invention uses the maximum temperature of the internal device of the limiter under the action of high-power microwave pulse signals reaching the melting point of silicon material as the failure criterion of thermal damage to the limiter.

[0069] Furthermore, obtaining the internal thermal breakdown damage position of the limiter includes:

[0070] Based on the temperature field, determine the maximum temperature area inside the limiter;

[0071] When the maximum temperature of the maximum temperature area reaches the melting point, thermal breakdown occurs and the thermal breakdown damage position is obtained.

[0072] Specifically, the limiter circuit model in the present invention can accurately simulate the real-time distribution of the electric field, temperature field, etc. inside the limiter device under the action of high-power microwave pulses. The temperature field can be used to determine the area where the maximum temperature inside the limiter device is located. When the maximum temperature reaches the melting point, thermal breakdown damage failure occurs.

[0073] The region where the maximum temperature of the limiter in the present invention rises to the melting point is the location where thermal damage to the limiter occurs.

[0074] The basic process of the electrical failure simulation method of the cascaded PIN limiter in the present invention is as follows: Figure 1 As shown in the figure, by converting the transmission line in the cascaded PIN limiter into an equivalent lumped circuit element, a field-circuit collaborative multi-physics field simulation circuit model of the limiter is established. With the help of this model, the electric field, temperature field and other responses of the internal devices of the limiter during the action of high-power microwave pulses can be obtained when solving the electrical characteristics of the limiter. In order to consider the influence of the temperature distribution of the device material on the conductivity and specific heat capacity, the temperature dependence equations of the specific heat capacity and thermal conductivity of silicon are obtained, and the physical model of the thermal conductivity and specific heat capacity of the limiter circuit is corrected. Finally, with the help of this limiter field-circuit model, the thermal damage failure study of the limiter under the action of high-power microwave pulse signals is carried out, and the breakdown damage position of the limiter under the action of high-power microwave pulse signals is determined.

[0075] The actual structure diagram of the limiter in the present invention is as follows: Figure 2As shown. The limiter is mainly composed of a PIN diode 2 (denoted as PIN1) at the input port, a PIN diode 3 (denoted as PIN2) at the output port, a microstrip line connecting the two PIN diodes, and an RF choke inductor that passes direct current. When using the limiter field-circuit collaborative simulation circuit model to analyze and calculate the electrical and thermal characteristics of the limiter, a transmission line model cannot be established. However, the transmission line plays a very important role in the limiter, so the invention uses the transmission line equivalent theory to convert it into the corresponding circuit R, L, C components, where C includes the input port DC blocking capacitor 5 and the output port DC blocking capacitor 6.

[0076] In the present invention, according to the transmission path of the limiter signal and the connection relationship between each circuit element, Figure 2 The limiter circuit shown is equivalent to Figure 3 The five two-port microwave network series circuit structures shown in the figure are PIN1, one-eighth wavelength transmission line, RF choke inductor 4, one-eighth wavelength transmission line, and PIN2. In numerical simulation, the circuit models of limiter diodes PIN1, PIN2, and inductor L can be directly established. However, the distributed parameter model of the transmission line cannot be directly established, and it needs to be equivalent to the corresponding circuit elements.

[0077] The two-port microwave network structure of a single one-eighth wavelength transmission line in the present invention is as follows: Figure 4 The structural dimension parameters of the transmission line can be used to obtain the electrical characteristic parameters of the transmission line, which can be expressed using the transmission matrix. Figure 4 The relationship between the voltage and current at port 1 and port 2 of the transmission line is:

[0078]

[0079] Specifically, it is expressed in matrix form:

[0080]

[0081] When the transmission matrix is ​​used in the present invention to represent the voltage and current relationship between the two ends of the transmission line, the Z matrix of the two-port microwave network can be obtained according to the ABCD matrix formula of the two-port microwave network.

[0082] In the present invention, the direction of the current I2 in the Z matrix is ​​expressed as Figure 4 The direction shown, then:

[0083]

[0084] The present invention obtains an equivalent R, L, C circuit of a λ / 8 transmission line, and its specific structure is as follows: Figure 5 shown.

[0085] The present invention combines the equivalent circuit of two sections of one-eighth wavelength transmission lines with PIN1, radio frequency choke inductor, and PIN2 according to Figure 3 The sequence shown in the figure is connected in sequence, and finally the field-path cooperative circuit model of the cascaded PIN diode limiter is obtained, as shown in Figure 6 shown.

[0086] The present invention utilizes the field-path coordination circuit of the limiter, and the limiting characteristic curve of the limiter obtained by simulation is as follows: Figure 7 As shown in the figure. It can be seen from the figure that when the input power is lower than 17dBm, the insertion loss is very small and the limiter hardly has any limiting effect. When the input power is higher than 17dBm, the limiter begins to play a limiting role. When the limiter equivalent circuit in the invention is used for simulation, the limiting characteristic curve of the limiter can be well obtained.

[0087] In order to utilize the limiter circuit model to perform damage failure analysis of the limiter, the present invention modifies the thermal parameter model of semiconductor material silicon in the limiter under high temperature conditions.

[0088] Specifically, the invention obtains the temperature dependence equation of silicon thermal conductivity through experimental testing:

[0089] χ = -3.22 × 10 -7 ×T 2 +0.004257×T-0.5020 (4)

[0090] Specifically, the invention obtains the temperature dependence equation of the specific heat capacity of silicon through testing:

[0091] c L =1.063+0.002513×T-1.339×10 -6 ×T 2 +3.124×10 -10 ×T 3 (5)

[0092] The present invention utilizes a limiter circuit to conduct damage failure research under the action of a high-power microwave pulse signal and determine the limiter damage failure position.

[0093] Specifically, the present invention obtains the spatial distribution of the temperature field of the PIN diode at the input end when the limiter thermal damage failure occurs as follows: Figure 8 As shown, the limiting thermal damage failure position is determined to be the middle of the input PIN diode I region.

[0094] The above are only preferred specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A method for simulating electrothermal failure of a cascaded PIN diode limiter based on field-circuit synergy, characterized in that: include: The transmission line in the cascaded PIN limiter is converted into an equivalent lumped circuit element, and a field-circuit co-simulation model of the limiter is established based on the lumped circuit element; Respectively obtaining a temperature dependence equation of the specific heat capacity of silicon and a temperature dependence equation of the thermal conductivity of silicon, and correcting the physical model of the thermal conductivity and specific heat capacity of the limiter circuit based on the temperature dependence equation of the specific heat capacity and the temperature dependence equation of the thermal conductivity; Based on the field-circuit collaborative simulation model and the physical model, combined with the thermal damage criterion of the limiter under the action of high-power microwave pulses, the temperature field and electric field distribution inside the limiter are obtained; Based on the temperature field and electric field distribution, the internal thermal breakdown damage position of the limiter is obtained.

2. The method for simulating electrothermal failure of a cascaded PIN diode limiter based on field-circuit synergy according to claim 1, characterized in that: Converting the transmission line in the cascaded PIN limiter into an equivalent lumped circuit element involves: Divide the first wavelength transmission line into two second wavelength transmission lines of equal length, wherein the wavelength of the first wavelength transmission line is twice the wavelength of the second wavelength transmission line; The two-port microwave networks of the two equal-length second wavelength transmission lines are converted into corresponding circuit elements.

3. The method for simulating electrothermal failure of a cascaded PIN diode limiter based on field-circuit synergy according to claim 2, characterized in that: The method of converting the two-port microwave network of two equal-length one-eighth wavelength transmission lines into corresponding circuit elements is as follows: V1=I1Z 11 -I2Z 12 <h2 style=";text-align:left;direction:ltr">V2=I1Z<h2 style=";text-align:left;direction:ltr"> 21 <h2 style=";text-align:left;direction:ltr"> -I2Z<h2 style=";text-align:left;direction:ltr"> 22 Where V1 and I1 are the voltage and current at the input port, V2 and I2 are the voltage and current at the output port, and Z 11 and Z 22 are the voltage and current transfer coefficients, Z 12 is the transfer impedance, Z 21 is the transfer admittance.

4. The method for simulating electrothermal failure of a cascaded PIN diode limiter based on field-circuit synergy according to claim 2, characterized in that: The field-circuit collaborative simulation model of the limiter includes: a first-stage diode, two sections of second-wavelength transmission lines, a radio frequency choke inductor and a second-stage diode; Wherein, the first-stage diode, the second wavelength transmission line, the radio frequency choke inductor, the second wavelength transmission line and the second-stage diode are connected in sequence.

5. The method for simulating electrothermal failure of a cascaded PIN diode limiter based on field-circuit synergy according to claim 1, characterized in that: The method for obtaining the temperature dependence equation of the specific heat capacity is: x=-3.22×10 -7 ×T 2 +0.004257×T-0.5020 Where χ is the thermal resistivity coefficient and T is the temperature.

6. The method for simulating electrothermal failure of a cascaded PIN diode limiter based on field-circuit synergy according to claim 1, characterized in that: The method to obtain the temperature dependence equation of the thermal conductivity is: c L =1.063+0.002513×T-1.339×10 -6 ×T 2 +3.124×10 -10 ×T 3 Among them, c L is the thermal capacitance coefficient and T is the device temperature.

7. The method for simulating electrothermal failure of a cascaded PIN diode limiter based on field-circuit synergy according to claim 1, characterized in that: The thermal damage criterion of the limiter under the action of the high-power microwave pulse is: The maximum temperature of the internal components of the limiter reaching the melting point of the material under the action of high-power microwave pulse signal is taken as the failure criterion of thermal damage of the limiter.

8. The method for simulating electrothermal failure of a cascaded PIN diode limiter based on field-circuit synergy according to claim 1, characterized in that: Obtaining the internal thermal breakdown damage position of the limiter includes: Based on the temperature field, determining a maximum temperature region inside the limiter; When the maximum temperature of the maximum temperature area reaches the melting point, thermal breakdown occurs, and the thermal breakdown damage position is obtained.

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