Thyristor based on compatible temperature sensor and preparation method thereof

Abstract

The invention discloses a compatible temperature sensor-based thyristor and a preparation method thereof. The compatible temperature sensor-based thyristor comprises a substrate, a buffer layer, a drift layer, a base region, a compatible sensor, a plurality of electrode arrays and a cathode. According to the invention, the semiconductor device is used as the compatible temperature sensor, and the compatible temperature sensor made of the semiconductor device has the advantages of high linearity and sensitivity; the compatible temperature sensor is integrated in the thyristor, so that the integration level of a power device is improved, and a temperature measurement system of the thyristor is more compact and efficient. According to the technology, the internal temperature of the thyristor can be monitored in real time, the accuracy and the real-time performance of a measurement result are ensured, and a powerful guarantee is provided for stable operation of a thyristor power electronic system. After the compatible temperature sensor is integrated, the basic working characteristics of the thyristor are not affected, and excellent performance and reliability are still kept. And the thyristor terminal is used as an isolation region, so that the process compatibility is realized, and the process steps are saved.

Description

Technical Field

[0001] The invention belongs to the technical field of semiconductor manufacturing, and in particular relates to a thyristor based on a compatible temperature sensor and a preparation method thereof. Background Art

[0002] Silicon carbide thyristors have the advantages of excellent current handling capability, high blocking voltage, high operating temperature and high operating frequency, but with the above excellent performance, they also bring a lot of reliability problems. In the use of power devices such as thyristors, many temperature-related problems are often encountered. The increase in operating temperature will not only reduce the long-term working reliability of the device, but also in application scenarios such as short circuits, pulses and switches, high temperature will cause thermal failure of the device, thereby causing irreversible damage to the system. Taking silicon carbide thyristors as an example, they need to withstand higher current peaks in pulse switching systems. High currents may cause the anode metal to melt or the device leakage current to slowly increase under repeated discharge thermoelectric stress, resulting in device failure, reducing the reliability of the pulse power system.

[0003] At present, in order to monitor the temperature change of thyristors, an external temperature measurement circuit or the shell temperature of the thyristor is generally used. The external temperature measurement circuit generally collects the characteristic parameters of the thyristor when it is working, and calculates the junction temperature by establishing a thermal resistance model in the data calculation module.

[0004] The existing monitoring system for thyristor temperature changes has the disadvantages of being unable to monitor the internal junction temperature changes of the thyristor in real time, inaccurately measuring the temperature, affecting the operation of the thyristor, occupying a large area, and having a low integration level. Summary of the invention

[0005] In order to solve the above problems existing in the prior art, the present invention provides a thyristor based on a compatible temperature sensor and a preparation method thereof. The technical problem to be solved by the present invention is achieved by the following technical solutions:

[0006] In a first aspect, the present invention provides a thyristor based on a compatible temperature sensor, comprising:

[0007] substrate, a buffer layer, a drift layer, a base region, a compatible temperature sensor, a plurality of electrode arrays, a cathode and a terminal; wherein,

[0008] The substrate, the buffer layer, the drift layer and the base region are arranged in sequence from bottom to top; the structure formed by the drift layer and the base region has two grooves, the depth of the grooves exceeds the thickness of the base region and does not exceed the thickness of the drift layer; the terminal is arranged in the drift layer below the groove;

[0009] The compatible temperature sensor is arranged between the two grooves; the compatible temperature sensor is a PiN temperature sensor that uses the terminal as its own isolation area;

[0010] The electrode array is symmetrically arranged on the base area on both sides of the compatible sensor;

[0011] The cathode is arranged on the lower surface of the substrate.

[0012] In one embodiment of the present invention, the material of the substrate includes silicon carbide; the doping type of the substrate is N-type heavy doping, and the doping concentration is 1×10 18 -5×10 19 cm -3 .

[0013] In one embodiment of the present invention, the material of the buffer layer includes: silicon carbide with a thickness of 1-3 μm; the buffer layer is P-type lightly doped with a doping concentration of 1×10 17 -8×10 17 cm -3 .

[0014] In one embodiment of the present invention, the material of the drift layer includes: silicon carbide with a thickness of 20-40 μm; the drift layer is P-type lightly doped with a doping concentration of 1×10 15 -6×10 15 cm -3 .

[0015] In one embodiment of the present invention, the material of the base region includes: silicon carbide with a thickness of 4-6 μm; the base region is N-type lightly doped with a doping concentration of 1×10 17 -3×10 17 cm -3 .

[0016] In one embodiment of the present invention, the compatible sensor comprises:

[0017] Isolation region, i region, P region, N region, sensor anode, sensor cathode and isolation electrode; wherein,

[0018] The isolation region is composed of a portion of the drift layer between the terminals;

[0019] The i-region is composed of a base region portion on the upper surface of a drift layer portion between the terminals;

[0020] The P region is disposed on an upper surface of one end of the i region;

[0021] The N region is arranged in the top layer region at the other end of the i region;

[0022] The sensor anode is arranged on the upper surface of the P region;

[0023] The sensor cathode is disposed on the upper surface of the N region;

[0024] The isolation electrode is arranged on the upper surface of the terminal.

[0025] In one embodiment of the present invention, the electrode array comprises:

[0026] an anode layer, an anode, two gate electrode regions and two gate electrodes; wherein,

[0027] The anode layer is arranged on the upper surface of the base region;

[0028] The anode is disposed on the upper surface of the anode layer;

[0029] Two gate electrode regions are respectively arranged in the base region on both sides of the anode layer;

[0030] The two gate electrodes are respectively arranged on the upper surfaces of the corresponding gate electrode regions.

[0031] In one embodiment of the present invention, the thickness of the terminal is 0.5-2 μm and the width is 3-7 μm; the terminal is N-type doped with a doping concentration of 1×10 18 -5×10 18 cm -3 .

[0032] In a second aspect, the present invention provides a method for preparing a thyristor based on a compatible temperature sensor, comprising:

[0033] Selecting a substrate, performing epitaxial growth and multi-layer ion implantation on the substrate to obtain a buffer layer, a drift layer, a base region and a silicon carbide P-type anode layer;

[0034] Using a preset photolithography mask, etching the silicon carbide P-type anode layer into the drift layer to form two grooves and a sensor area between the two grooves;

[0035] The etched silicon carbide P-type anode layer is etched again to form a plurality of anode layers on a portion of the base region on both sides of the sensor region, and a P region is formed on a portion of the base region in the sensor region;

[0036] Ion implantation is performed on partial areas of the base region on both sides of the anode layer, partial areas of the bottoms of the two grooves close to the sensor region, and partial areas of the base region in the sensor region away from the P region to form a plurality of gate electrode regions, terminals, and N regions respectively;

[0037] A gate electrode is prepared on the upper surface of the gate electrode region, an anode is prepared on the upper surface of the anode layer, a sensor anode is prepared on the upper surface of the P region, a sensor cathode is prepared on the upper surface of the N region, and an isolation electrode is prepared on the upper surface of the terminal; a portion of the drift layer between the terminals constitutes an isolation region, and a portion of the base region in the sensor region constitutes an i region; the isolation region, the i region, the P region, the N region, the sensor anode, the sensor cathode and the isolation electrode constitute a compatible sensor; the anode layer, the anode, the two gate electrode regions on both sides of the anode layer and the corresponding two gate electrodes constitute an electrode array;

[0038] A cathode is prepared on the lower surface of the substrate.

[0039] Beneficial effects of the present invention:

[0040] In the solution provided by the present invention, semiconductor devices are used as compatible temperature sensors. The compatible temperature sensors made of semiconductor devices have the advantages of high linearity and sensitivity. The compatible temperature sensors are integrated inside the thyristors to improve the integration of power devices. The compatible temperature sensors are combined with thyristors to make the thyristor temperature measurement system more compact and efficient. At the same time, this technology can monitor the temperature inside the thyristors in real time, ensure the accuracy and real-time nature of the measurement results, and provide a strong guarantee for the stable operation of the thyristor power electronic system. More importantly, after the compatible temperature sensor is integrated, the basic working characteristics of the thyristors are not affected, and excellent performance and reliability are still maintained. In addition, the thyristor terminals are used as isolation areas to achieve process compatibility and save process steps. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 A schematic diagram of a process flow of a thyristor based on a compatible temperature sensor provided by an embodiment of the present invention;

[0042] Figure 2 A simulation diagram of the isolation effect of a thyristor based on a compatible temperature sensor provided in an embodiment of the present invention;

[0043] Figure 3 A temperature variation diagram during a switching process of a thyristor based on a compatible temperature sensor provided by an embodiment of the present invention;

[0044] Figure 4 A graph showing the relationship between the operating voltage and current of a terminal process compatible temperature sensor provided by an embodiment of the present invention over time;

[0045] Figure 5 A relationship diagram between a measured temperature based on a terminal process compatible temperature sensor and an actual temperature of a thyristor provided in an embodiment of the present invention;

[0046] Figure 6a-6c A simulation result diagram of forward conduction characteristics, switching characteristics and forward blocking characteristics of a thyristor integrated with a compatible temperature sensor and a thyristor without an integrated compatible sensor provided in an embodiment of the present invention;

[0047] Figure 7 A schematic diagram of the steps of a method for preparing a thyristor based on a compatible temperature sensor provided by an embodiment of the present invention;

[0048] Figure 8a-8d A schematic diagram of a process of a thyristor based on a compatible temperature sensor provided in an embodiment of the present invention.

[0049] Reference numerals

[0050] 1-substrate, 2-buffer layer, 3-drift layer, 4-base region, 5-compatible sensor, 6-electrode array, 7-cathode, 8-terminal, 51-isolation region, 52-i region, 53-P region, 54-N region, 55-sensor anode, 56-sensor cathode, 57-isolation electrode, 61-anode layer, 62-anode, 63-gate electrode region, 64-gate electrode. DETAILED DESCRIPTION

[0051] 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.

[0052] In order to achieve the purpose of real-time monitoring of the temperature inside a thyristor without affecting the normal operation of the thyristor, an embodiment of the present invention provides a thyristor based on a compatible temperature sensor and a preparation method thereof.

[0053] Below, firstly, a thyristor based on a compatible temperature sensor provided in an embodiment of the present invention is introduced.

[0054] like Figure 1 As shown, a thyristor based on a compatible temperature sensor provided by an embodiment of the present invention may include:

[0055] Substrate 1, buffer layer 2, drift layer 3, base region 4, compatible temperature sensor 5, multiple electrode arrays 6, cathode 7 and terminal 8; wherein,

[0056] The substrate 1, the buffer layer 2, the drift layer 3 and the base region 4 are arranged in sequence from bottom to top; the structure formed by the drift layer 3 and the base region 4 has two grooves, the depth of the grooves exceeds the thickness of the base region, but does not exceed the thickness of the drift layer; the terminal 8 is arranged in the drift layer below the groove;

[0057] The compatible temperature sensor 5 is disposed between the two grooves; the compatible temperature sensor 5 is a PiN temperature sensor that uses the terminal 8 as its own isolation area;

[0058] The electrode array 6 is symmetrically arranged on the base area 4 on both sides of the compatible sensor 5;

[0059] The cathode 7 is disposed on the lower surface of the substrate 1 .

[0060] The embodiment of the present invention proposes a thyristor based on a compatible temperature sensor, which can monitor the temperature change inside the thyristor in real time. The thyristor integrated with the compatible temperature sensor can work normally and has a high degree of integration. The use of the terminal of the thyristor as an isolation area can achieve process compatibility and reduce process steps.

[0061] Preferably, the material of the substrate 1 may include silicon carbide; the doping type of the substrate 1 is N-type heavy doping, and the doping concentration is 1×10 18 -5×10 19 cm -3 .

[0062] Preferably, the material of the buffer layer 2 may include: silicon carbide with a thickness of 1-3 μm; the buffer layer 2 is P-type lightly doped with a doping concentration of 1×10 17 -8×10 17 cm -3 .

[0063] It can be understood that the functions of the buffer layer in the thyristor may include:

[0064] Prevent overvoltage and overcurrent: When the thyristor is turned on and off, voltage spikes and overvoltage will be generated due to the inductance in the circuit. The buffer layer absorbs these voltage spikes to prevent the thyristor from being damaged by overvoltage.

[0065] Reduce switching losses: The buffer layer reduces the loss of the thyristor during the switching process by limiting the rate of change of current and voltage, thereby extending its service life.

[0066] Suppressing transient overvoltage: When the thyristor is turned off, the power supply voltage will suddenly be added to the thyristor, generating a transient overvoltage. The buffer layer can also suppress this transient overvoltage through a parallel RC network to prevent the thyristor from being triggered by mistake due to excessive junction capacitance current flowing inside the thyristor.

[0067] Through these functions, the buffer layer ensures the stability and reliability of the thyristor during the switching process, protects the device from damage, and improves the performance of the overall circuit.

[0068] Preferably, the material of the drift layer 3 may include: silicon carbide with a thickness of 20-40 μm; the drift layer 3 is P-type lightly doped with a doping concentration of 1×10 15 -6×10 15 cm -3 .

[0069] It is understandable that the working principle of the drift layer is based on its lightly doped characteristics. Due to the low doping concentration, the number of carriers in the drift layer is small, resulting in poor conductivity and high resistance. This characteristic enables the drift layer to remain stable under high voltage and will not be broken down due to excessive voltage.

[0070] Preferably, the material of the base region 4 may include: silicon carbide with a thickness of 4-6 μm; the base region 4 is N-type lightly doped with a doping concentration of 1×10 17 -3×10 17 cm -3 .

[0071] It can be understood that the functions of the base region in a thyristor may include:

[0072] Controlling the opening and closing of the thyristor: The base region plays a key role in the thyristor. By controlling the current between the base region and the cathode, the thyristor can be opened and closed. When a positive voltage is applied to the gate electrode, a current channel is formed between the base region and the cathode, thereby turning on the thyristor; conversely, when a negative voltage is applied, the channel is cut off and the thyristor is turned off.

[0073] Providing internal positive feedback: The thyristor contains two sub-transistors, a pnp transistor and an npn transistor. When a base current is given to the npn transistor, it pulls an amplified current from the collector, which then provides the base current to the pnp transistor, forming an internal positive feedback loop. This positive feedback mechanism allows the thyristor to remain in the on state after being turned on, and even if the gate drive current is removed, the thyristor can still remain in the on state.

[0074] Influence on the performance of thyristors: The structure and parameters of the base region have an important influence on the performance of thyristors. For example, the doping concentration and thickness of the base region will affect the turn-on voltage and on-resistance of the thyristor. A higher doping concentration and a thinner base region can reduce the turn-on voltage, but may increase the on-resistance; conversely, a lower doping concentration and a thicker base region will increase the turn-on voltage but reduce the on-resistance.

[0075] Preferably, the compatible sensor 5 may include:

[0076] Isolation region 51, i region 52, P region 53, N region 54, sensor anode 55, sensor cathode 56 and isolation electrode 57; wherein,

[0077] The isolation region 51 is formed by a portion of the drift layer between the terminals 8;

[0078] The i region 52 is formed by a partial region of the base region on the upper surface of a partial region of the drift layer between the terminals 8;

[0079] The P region 53 is disposed at one end of the upper surface of the i region 52;

[0080] The N region 54 is disposed at the other end of the upper surface of the i region 52;

[0081] The sensor anode 55 is disposed on the upper surface of the P region 53;

[0082] The sensor cathode 56 is disposed on the upper surface of the N region 54;

[0083] The isolation electrode 57 is disposed on the upper surface of the terminal 8 .

[0084] Preferably, the thickness of the terminal 8 is 0.5-2 μm, and the width is 3-7 μm; the terminal 8 is N-type doped, and the doping concentration is 1×10 18 -5×10 18 cm -3 .

[0085] In order to ensure that the compatible sensor integrated in the thyristor can work properly, it is necessary to use PN junction isolation in the compatible sensor for isolation, that is, bias a positive voltage at the isolation electrode of the sensor. For specific isolation effect simulation diagrams of compatible sensors, please refer to Figure 2 As shown in the figure, it can be observed from the electric field lines during simulation that the terminal structure achieves the expected isolation effect. When the thyristor is working, a constant current source needs to be biased for the PiN temperature sensor. When the working current is constant, the working voltage and temperature of the PiN temperature sensor are approximately linear. The temperature inside the thyristor can be obtained by the voltage drop of the temperature sensor.

[0086] It can be understood that the thyristor based on a compatible temperature sensor provided in an embodiment of the present invention adopts a semiconductor device as a temperature sensor. The temperature sensor made of the semiconductor device has the advantages of high linearity and sensitivity. The semiconductor temperature sensor is integrated inside the thyristor, which improves the integration of the power device and can monitor the temperature changes inside the thyristor in real time.

[0087] Preferably, the electrode array 6 may include:

[0088] Anode layer 61, anode 62, two gate electrode regions 63 and two gate electrodes 64; wherein,

[0089] The anode layer 61 is disposed on the upper surface of the base region 4;

[0090] The anode 62 is disposed on the upper surface of the anode layer 61;

[0091] Two gate electrode regions 63 are respectively arranged in the base region 4 on both sides of the anode layer 61;

[0092] The two gate electrodes 64 are respectively disposed on the upper surfaces of the corresponding gate electrode regions 63 .

[0093] Optionally, four electrode arrays may be provided, wherein two electrode arrays are provided on one side of the compatible sensor 5 , and two electrode arrays are provided on the other side of the compatible sensor 5 .

[0094] In order to verify the feasibility and beneficial effects of the thyristor based on the compatible temperature sensor provided in the embodiment of the present invention, a switching circuit is selected to be built for simulation. The temperature change during the actual switching process of the thyristor and the working condition of the integrated compatible temperature sensor are simulated by setting the material parameters and thermal resistance coefficient of silicon carbide. For the temperature change diagram during the switching process, please refer to Figure 3 As shown, from Figure 3 It can be seen that the temperature change of the thyristor mainly occurs during the shutdown process. The reason is that during the shutdown process, the thyristor needs to withstand a large voltage and current, so the temperature changes greatly. The working voltage of the compatible temperature sensor will also change during the shutdown process. For the relationship between the working voltage and current of the compatible temperature sensor over time, please refer to Figure 4 As shown, from Figure 4 It can be seen that when the working current of the compatible temperature sensor is constant, the voltage drop of the sensor will decrease as the temperature increases, and the sensor voltage drop is linearly related to the temperature, so the corresponding temperature can be calculated from the sensor voltage drop.

[0095] For a diagram showing the relationship between the temperature measured by a compatible temperature sensor and the actual temperature of the thyristor, see Figure 5 ,from Figure 5 It can be seen that the error of comparing the temperature calculated by the compatible temperature sensor with the temperature inside the thyristor is small and does not exceed 2 Kelvin.

[0096] The forward conduction characteristics, switching characteristics and forward blocking characteristics of the thyristor with integrated compatible temperature sensor and the thyristor without integrated compatible sensor are simulated. The simulation results are as follows: Figure 6a , Figure 6b and Figure 6c ; For a comparison of the forward conduction characteristics of the thyristor with integrated compatible temperature sensor and the thyristor without integrated compatible temperature sensor, see Figure 6a , the switching characteristics comparison diagram of the thyristor with integrated compatible temperature sensor and the thyristor without integrated compatible temperature sensor, please refer to Figure 6b , the forward blocking characteristics comparison of the thyristor with integrated compatible temperature sensor and the thyristor without integrated compatible temperature sensor, please refer to Figure 6c ;from Figure 6a , Figure 6b and Figure 6c It can be seen from the simulation results in that the basic working characteristics of the thyristor are not affected after the compatible temperature sensor is integrated.

[0097] In a second aspect, corresponding to the above thyristor embodiment, the embodiment of the present invention further provides a method for preparing a thyristor based on a compatible temperature sensor, such as Figure 7 As shown, the preparation method may include:

[0098] S1, selecting a substrate 1, performing epitaxial growth and multi-layer ion implantation on the substrate 1, and obtaining a buffer layer 2, a drift layer 3, a base region 4 and a silicon carbide P-type anode layer.

[0099] Specifically, during the preparation process, the doping type of the substrate 1 is selected as N-type heavy doping, and the doping concentration is 1×10 18 -5×10 19 cm -3 After obtaining the substrate 1, a P-type lightly doped substrate with a thickness of 1-3 μm and a doping concentration of 1×10 17 -8×10 17 cm -3 Then, a buffer layer 2 with a thickness of 20-40 μm and lightly doped P type with a doping concentration of 1×10 15 -6×10 15 cm -3 Next, a drift layer 3 with a thickness of 4-6 μm is formed, which is lightly doped with N type and a doping concentration of 1×10 17 -3×10 17 cm -3 Finally, a base region with a thickness of 1-3 μm and a doping concentration of 1×10 18 -5×10 19 cm -3 Silicon carbide P-type anode layer.

[0100] S2, using a preset photolithography mask to etch the silicon carbide P-type anode layer into the base region 4, to form two grooves and a sensor region between the two grooves.

[0101] The silicon carbide P-type anode layer is etched using a preset photolithography mask. The specific etching depth is greater than the sum of the thickness of the silicon carbide P-type anode layer and the thickness of the base region 4, and less than the sum of the thickness of the silicon carbide P-type anode layer, the thickness of the base region 4 and the drift layer 3. Therefore, the bottom of the groove obtained by etching is located in the drift layer 3. Finally, two grooves and a sensor area are formed in the drift layer 3 and the base region 4. The obtained device is as follows: Figure 8a shown.

[0102] S3, the etched silicon carbide P-type anode layer is etched again to form a plurality of anode layers 61 on partial areas of the base region on both sides of the sensor region, and a P region is formed on partial areas of the base region in the sensor region.

[0103] Specifically, after the corresponding position of the etched silicon carbide P-type anode layer is etched again, a plurality of anode layers 61 and a P region 53 are formed, and the obtained device is as follows: Figure 8b shown.

[0104] S4, ion implantation is performed on partial areas of the base region on both sides of the anode layer 61, partial areas of the bottom of the two grooves close to the sensor region, and partial areas of the base region in the sensor region away from the P region 53, to form multiple gate electrode regions 63, terminals 8 and N regions 54 respectively.

[0105] Specifically, ion implantation is performed on a part of the base region on both sides of the anode layer 61 to form a plurality of gate electrode regions 63, ion implantation is performed on a part of the bottom of the two grooves close to the sensor region to form a terminal 8, and ion implantation is performed on a part of the base region away from the P region 53 in the sensor region to form an N region 54. The device obtained is as follows: Figure 8c shown.

[0106] S5, prepare a gate electrode 64 on the upper surface of the gate electrode region 63, prepare an anode 62 on the upper surface of the anode layer 61, prepare a sensor anode 55 on the upper surface of the P region 53, prepare a sensor cathode 56 on the upper surface of the N region 54, and prepare an isolation electrode 57 on the upper surface of the terminal 8; the partial area of ​​the drift layer between the terminal 8 and the terminal constitutes the isolation region 51, and the partial area of ​​the base region on the upper surface of the partial area of ​​the drift layer between the terminals constitutes the i region 52; the isolation region 51, the i region 52, the P region 53, the N region 54, the sensor anode 55, the sensor cathode 56 and the isolation electrode 57 constitute a compatible sensor 5; the anode layer 61, the two gate electrode regions 63 of the anode 62 and the two gate electrodes 64 constitute an electrode array 6.

[0107] It can be understood that the compatible sensor proposed in the embodiment of the present invention can be formed simultaneously with the thyristor lithography, without the need for additional steps such as ion implantation, and the doping concentration of the compatible sensor is consistent with that of the thyristor. The integrated compatible sensor is located between the two N-type terminals in the thyristor. The terminals of the thyristor are used as the isolation area of ​​the temperature sensor to achieve process compatibility and reduce process steps. The thyristor uses a semiconductor device as a temperature sensor. The temperature sensor made of a semiconductor device has the advantages of high linearity and sensitivity; the semiconductor temperature sensor is integrated inside the thyristor to improve the integration of the power device, and at the same time, it can monitor the temperature changes inside the thyristor in real time.

[0108] Specifically, in the process of preparing the gate electrode, nickel metal is deposited on the upper surface of the gate electrode region 63 by magnetron sputtering, and then thermal annealing is performed under a first preset annealing condition to form a good N-type ohmic contact; wherein the first preset annealing condition can be selected to be set to: annealing temperature 950°C, annealing time 15 minutes. In the process of preparing the anode, aluminum metal is deposited on the upper surface of the anode layer 61 by magnetron sputtering, and then thermal annealing is performed under a second preset annealing condition to form a good P-type ohmic contact; wherein the second preset annealing condition can be selected to be set to: annealing temperature 1000°C, annealing time 2 minutes.

[0109] S6, preparing a cathode 7 on the lower surface of the substrate 1.

[0110] In the process of preparing the cathode, nickel metal is deposited on the lower surface of the substrate 1 by magnetron sputtering, and then thermal annealing is performed under the third preset annealing condition to form a good N-type ohmic contact; wherein the third preset annealing condition can be selected to be set to: annealing temperature 950°C, annealing time 15 minutes. It can be understood that the preparation method of the corresponding sensor anode, sensor cathode and isolation electrode in the compatible sensor is similar to the preparation method of the above-mentioned electrodes, and will not be elaborated here. After executing step S6, the final thyristor, such as Figure 8d shown.

[0111] The thyristor based on the compatible temperature sensor provided in the embodiment of the present invention adopts a semiconductor device as a compatible temperature sensor. The compatible temperature sensor made of the semiconductor device has the advantages of high linearity and sensitivity. The compatible temperature sensor is integrated inside the thyristor to improve the integration of the power device. The compatible temperature sensor is combined with the thyristor to make the thyristor temperature measurement system more compact and efficient. At the same time, this technology can monitor the temperature inside the thyristor in real time, ensure the accuracy and real-time performance of the measurement results, and provide a strong guarantee for the stable operation of the thyristor power electronic system. More importantly, after the compatible temperature sensor is integrated, the basic working characteristics of the thyristor are not affected, and the excellent performance and reliability are still maintained. In addition, the thyristor terminal is used as the isolation area to achieve process compatibility and save process steps.

[0112] It should be noted that in the description of the present invention, it should be understood that the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0113] The above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. A thyristor based on a compatible temperature sensor, characterized in that: include: A substrate (1), a buffer layer (2), a drift layer (3), a base region (4), a compatible temperature sensor (5), a plurality of electrode arrays (6), a cathode (7) and a terminal (8); wherein: The substrate (1), the buffer layer (2), the drift layer (3) and the base region (4) are arranged in sequence from bottom to top; the structure formed by the drift layer (3) and the base region (4) has two grooves, the depth of the grooves exceeds the thickness of the base region but does not exceed the thickness of the drift layer; the terminal (8) is arranged in the drift layer below the groove; The compatible temperature sensor (5) is arranged between the two grooves; the compatible temperature sensor (5) is a PiN temperature sensor that uses the terminal (8) as its own isolation area; The electrode array (6) is symmetrically arranged on the base area (4) on both sides of the compatible sensor (5); The cathode (7) is arranged on the lower surface of the substrate (1).

2. A thyristor based on a compatible temperature sensor according to claim 1, characterized in that: The material of the substrate (1) includes silicon carbide; the doping type of the substrate (1) is N-type heavy doping, and the doping concentration is 1×10 18 -5×10 19 cm -3 .

3. A thyristor based on a compatible temperature sensor according to claim 1, characterized in that: The material of the buffer layer (2) includes: silicon carbide with a thickness of 1-3 μm; the buffer layer (2) is P-type lightly doped with a doping concentration of 1×10 17 -8×10 17 cm -3 .

4. A thyristor based on a compatible temperature sensor according to claim 1, characterized in that: The material of the drift layer (3) includes: silicon carbide with a thickness of 20-40 μm; the drift layer (3) is P-type lightly doped with a doping concentration of 1×10 15 -6×10 15 cm -3 .

5. The thyristor based on compatible temperature sensor according to claim 1, characterized in that: The material of the base region (4) includes: silicon carbide with a thickness of 4-6 μm; the base region (4) is N-type lightly doped with a doping concentration of 1×10 17 -3×10 17 cm -3 .

6. The thyristor based on compatible temperature sensor according to claim 1, characterized in that: The compatible sensor (5) comprises: An isolation region (51), an i region (52), a P region (53), an N region (54), a sensor anode (55), a sensor cathode (56) and an isolation electrode (57); wherein, The isolation region (51) is composed of a terminal (8) and a partial region of the drift layer between the terminals (8); The i-region (52) is composed of a base region portion of the upper surface of a drift layer portion between the terminals (8); The P region (53) is disposed on an upper surface of one end of the i region (52); The N region (54) is arranged in the top layer region at the other end of the i region (52); The sensor anode (55) is arranged on the upper surface of the P region (53); The sensor cathode (56) is disposed on the upper surface of the N region (54); The isolation electrode (57) is arranged on the upper surface of the terminal (8).

7. The thyristor based on compatible temperature sensor according to claim 1, characterized in that: The electrode array (6) comprises: an anode layer (61), an anode (62), two gate electrode regions (63) and two gate electrodes (64); wherein, The anode layer (61) is arranged on the upper surface of the base region (4); The anode (62) is arranged on the upper surface of the anode layer (61); Two gate electrode regions (63) are respectively arranged in the base region (4) on both sides of the anode layer (61); The two gate electrodes (64) are respectively arranged on the upper surfaces of the corresponding gate electrode regions (63).

8. The thyristor based on compatible temperature sensor according to claim 1, characterized in that: The terminal (8) has a thickness of 0.5-2 μm and a width of 3-7 μm; the terminal (8) is N-type doped with a doping concentration of 1×10 18 -5×10 18 cm -3 .

9. A method for preparing a thyristor based on a compatible temperature sensor, characterized in that: include: Selecting a substrate (1), performing epitaxial growth and multi-layer ion implantation on the substrate (1), and obtaining a buffer layer (2), a drift layer (3), a base region (4), and a silicon carbide P-type anode layer; Using a preset photolithography mask, the silicon carbide P-type anode layer is etched into the drift layer (3) to form two grooves and a sensor area located between the two grooves; The etched silicon carbide P-type anode layer is etched again to form a plurality of anode layers (61) on partial areas of the base region on both sides of the sensor region, and a P region (53) is formed on partial areas of the base region in the sensor region; Ion implantation is performed on partial areas of the base region on both sides of the anode layer (61), partial areas of the bottoms of the two grooves close to the sensor region, and partial areas of the base region in the sensor region away from the P region (53), to respectively form a plurality of gate electrode regions (63), terminals (8), and N regions (54); A gate electrode (64) is prepared on the upper surface of the gate electrode region (63), an anode (62) is prepared on the upper surface of the anode layer (61), a sensor anode (55) is prepared on the upper surface of the P region (53), a sensor cathode (56) is prepared on the upper surface of the N region (54), and an isolation electrode (57) is prepared on the upper surface of the terminal (8); a portion of the drift layer between the terminals (8) and the terminals (8) constitutes an isolation region (51), and a portion of the base region in the sensor region constitutes an i region (52); the isolation region (51), the i region (52), the P region (53), the N region (54), the sensor anode (55), the sensor cathode (56) and the isolation electrode (57) constitute a compatible sensor (5); the anode layer (61), the anode (62), two gate electrode regions (63) on both sides of the anode layer (61) and the corresponding two gate electrodes (64) constitute an electrode array (6); A cathode (7) is prepared on the lower surface of the substrate (1).

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