Terminal structure, preparation method of terminal structure, electronic equipment and vehicle

Abstract

The invention discloses a terminal structure, a preparation method of the terminal structure, electronic equipment and a vehicle, and the terminal structure comprises a substrate; an epitaxial layer of a first conductive type, wherein the epitaxial layer of the first conductive type grows on the substrate; an ion concentration adjusting region of a second conduction type, wherein the ion concentration adjusting region is located in the epitaxial layer and is close to the upper surface of the epitaxial layer; the doped columns of the second conduction type are located in the epitaxial layer and close to the upper surface of the epitaxial layer, and at least part of the doped columns are located in the ion concentration adjusting area. By adopting the terminal structure, the voltage endurance capability can be improved, and the risk that the terminal structure is broken down in advance is reduced.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to a terminal structure, a method for preparing the terminal structure, an electronic device and a vehicle. Background Art

[0002] The junction termination structure is an indispensable part of power devices. The existing terminal structure includes an ion concentration adjustment area such as a junction termination extension (JTE). The junction termination extension structure is very sensitive to surface charge and can easily affect the device surface electric field distribution due to interface instability and oxide layer charge, thereby affecting the device breakdown voltage and reliability. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, one object of the present invention is to provide a terminal structure, which can improve the voltage resistance and reduce the risk of premature breakdown of the terminal structure.

[0004] Another object of the present invention is to provide a method for preparing a terminal structure.

[0005] Another object of the present invention is to provide an electronic device.

[0006] Another object of the present invention is to provide a vehicle.

[0007] In order to solve the above problems, a terminal structure of an embodiment of the first aspect of the present invention includes: a substrate; an epitaxial layer of a first conductivity type, the epitaxial layer of the first conductivity type is grown on the substrate; an ion concentration adjustment region of a second conductivity type, the ion concentration adjustment region is located in the epitaxial layer and close to the upper surface of the epitaxial layer; at least one doped column of the second conductivity type, the doped column of the second conductivity type is located in the epitaxial layer and close to the upper surface of the epitaxial layer, and at least part of the doped column is located in the ion concentration adjustment region.

[0008] According to the terminal structure of the present invention, at least one doping column is arranged in the epitaxial layer and close to the upper surface of the epitaxial layer, and part of the doping column is arranged in the ion concentration adjustment zone. Therefore, when the ion dosage in the ion concentration adjustment zone is low, even if the ion concentration adjustment zone does not have enough immovable negative charges to offset the electric field in the original direction, the doping column can provide enough negative charges to attract the electric field, thereby achieving the purpose of sharing the surface electric field of the terminal structure, improving the voltage resistance, and reducing the risk of premature breakdown of the terminal structure.

[0009] According to some embodiments of the present invention, the terminal structure includes: a main junction, which is located in the epitaxial layer and close to the upper surface of the epitaxial layer, and the main junction and the ion concentration adjustment region are arranged along a second direction parallel to the substrate; the doped column is located on a side of the ion concentration adjustment region close to the main junction.

[0010] According to some embodiments of the present invention, the ion concentration adjustment region includes: a first junction terminal extension structure, in the second direction, the first junction terminal extension structure is in contact with the main junction, and the doped column is located in the first junction terminal extension structure and close to the main junction.

[0011] According to some embodiments of the present invention, the ion concentration adjustment zone includes: a second junction terminal extension structure and a third junction terminal extension structure, wherein the second junction terminal extension structure and the third junction terminal extension structure are both in contact with the main junction in the second direction, and the third junction terminal extension structure surrounds the bottom surface of the second junction terminal extension structure and the side surface of the second junction terminal extension structure away from the main junction.

[0012] According to some embodiments of the present invention, the doped column is located within the second junction termination extension structure and close to the main junction.

[0013] According to some embodiments of the present invention, the doping concentration of the second junction termination extension structure is higher than the doping concentration of the third junction termination extension structure.

[0014] According to some embodiments of the present invention, the ion concentration adjustment region includes: a lateral variable doping structure, which is in contact with the main junction in the second direction, and the thickness of the lateral variable doping structure in the first direction gradually decreases from one end close to the main junction to an end away from the main junction; the doping column is located in the lateral variable doping structure and close to the main junction.

[0015] According to some embodiments of the present invention, the terminal structure includes a plurality of the doped columns, each of the plurality of the doped columns extends along a first direction perpendicular to the substrate, and the plurality of the doped columns are arranged at intervals along the second direction.

[0016] According to some embodiments of the present invention, the number of the doped columns is N, wherein N satisfies: 2≤N≤3.

[0017] According to some embodiments of the present invention, the widths of the plurality of doped columns along the second direction are the same.

[0018] According to some embodiments of the present invention, the ion concentration adjustment region includes: at least one field limiting ring structure, at least one field limiting ring structure and the main junction are arranged at intervals in the second direction, part of the doped column is located in the field limiting ring structure, and in the second direction, the doped column is close to the side of the field limiting ring structure close to the main junction.

[0019] According to some embodiments of the present invention, the ion concentration adjustment region includes: a plurality of the field limiting ring structures, and the plurality of the field limiting ring structures are arranged at intervals in the second direction.

[0020] According to some embodiments of the present invention, the terminal structure includes: a plurality of the doped columns, the plurality of the doped columns are arranged corresponding to a plurality of the field limiting ring structures, and some of the doped columns are located in corresponding field limiting ring structures.

[0021] According to some embodiments of the present invention, a distance between the doped column closest to the main junction among the plurality of doped columns and the main junction is d1, wherein d1 satisfies: 4 μm≤d1≤5 μm.

[0022] According to some embodiments of the present invention, the terminal structure also includes: a trench stop ring, the trench stop ring is located in the epitaxial layer and close to the upper surface of the epitaxial layer, the trench stop ring is filled with a filling material, and in the second direction, the main junction, the ion concentration adjustment region and the trench stop ring are arranged at intervals.

[0023] According to some embodiments of the present invention, the terminal structure also includes: a second conductive type doped cutoff ring, which surrounds the side and bottom surfaces of the trench cutoff ring; a first conductive type cutoff ring, which is located in the epitaxial layer and close to the upper surface of the epitaxial layer, and in the second direction, the first conductive type cutoff ring is located on a side of the doped cutoff ring away from the ion concentration adjustment zone and is spaced apart from the doped cutoff ring.

[0024] According to some embodiments of the present invention, it also includes: a second conductivity type doped base region, the second conductivity type doped base region is located on a side of the substrate away from the first conductivity type epitaxial layer; a collector, the collector is located on a side of the second conductivity type doped base region away from the substrate; an emitter, the emitter is located on the upper surface of the first conductivity type epitaxial layer and in contact with the main junction; an oxide layer, the oxide layer is formed on the upper surface of the first conductivity type epitaxial layer, in the first direction, one end of the oxide layer extends to the emitter, and the other end extends to be flush with the first conductivity type epitaxial layer; a metal stop ring, the metal stop ring is located on the upper surface of the oxide layer, and in the second direction, is located at one end of the oxide layer corresponding to the trench stop ring.

[0025] According to an embodiment of the second aspect of the present invention, the present invention provides a method for preparing a terminal structure according to an embodiment of the first aspect of the present invention, comprising the following steps: preparing an epitaxial layer of a first conductivity type on the substrate along a first direction perpendicular to the substrate; preparing an ion concentration adjustment region of a second conductivity type and at least one doped column of the second conductivity type on the epitaxial layer, wherein the ion concentration adjustment region is located in the epitaxial layer and close to the upper surface of the epitaxial layer, the doped column is located in the epitaxial layer and close to the upper surface of the epitaxial layer, and at least part of the doped column is located in the ion concentration adjustment region.

[0026] According to the preparation method of an embodiment of the present invention, by setting at least one doping column in the epitaxial layer and close to the upper surface of the epitaxial layer, and setting part of the doping column in the ion concentration adjustment zone, when the ion concentration in the ion concentration adjustment zone is low, even if the ion concentration adjustment zone does not have enough immovable negative charges to offset the electric field in the original direction, the doping column can provide enough negative charges to attract the electric field, thereby achieving the purpose of sharing the electric field, improving the voltage resistance, and reducing the risk of premature breakdown of the terminal structure. According to some embodiments of the present invention, the preparation method also includes: preparing a main junction on the epitaxial layer, wherein the main junction is located in the epitaxial layer and close to the upper surface of the epitaxial layer, and along the first direction, the main junction is located on the left side of the ion concentration adjustment zone.

[0027] According to some embodiments of the present invention, the preparation method also includes: preparing a main junction on the epitaxial layer, wherein the main junction is located within the epitaxial layer and close to the upper surface of the epitaxial layer, and along a second direction parallel to the substrate, the main junction and the ion concentration adjustment region are spaced apart.

[0028] In some embodiments, a trench stop ring is prepared on the epitaxial layer, wherein the trench stop ring is located in the epitaxial layer and close to the upper surface of the epitaxial layer, and in the second direction, the trench stop ring is located on the side of the ion concentration adjustment region away from the main junction and is spaced apart from the ion concentration adjustment region.

[0029] According to some embodiments of the present invention, the preparation method also includes: along the first direction, preparing a second conductivity type doped base region and a collector on a side of the substrate away from the first conductivity type epitaxial layer, the second conductivity type doped base region is located on a side of the substrate away from the first conductivity type epitaxial layer, and the collector is located on a side of the second conductivity type doped base region away from the substrate; along the first direction, preparing an emitter, an oxide layer and a metal stop ring on the upper surface of the substrate, respectively, wherein the emitter is located on the upper surface of the first conductivity type epitaxial layer, and in the second direction, is located at the left end of the first conductivity type epitaxial layer and is in contact with the main junction, the oxide layer is formed on the upper surface of the first conductivity type epitaxial layer, and in the first direction, one end of the oxide layer extends to the emitter, and the other end extends to be flush with the first conductivity type epitaxial layer; the metal stop ring is located on the upper surface of the oxide layer, and in the first direction, is close to one end of the oxide layer corresponding to the trench stop ring.

[0030] A third aspect of the present invention provides an electronic device, comprising at least one terminal structure described in the above embodiment.

[0031] According to the electronic device of the embodiment of the present invention, by adopting the terminal structure of the above embodiment, the voltage resistance can be improved and the risk of premature breakdown of the terminal structure can be reduced.

[0032] A fourth aspect of the present invention provides a vehicle, comprising the electronic device described in the above embodiment.

[0033] According to the vehicle of the embodiment of the present invention, the pressure resistance can be improved and the risk of premature breakdown of the terminal structure can be reduced by adopting the electronic device of the above embodiment.

[0034] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0036] Figure 1 A schematic diagram of a terminal structure according to an embodiment of the present invention;

[0037] Figure 2 is a schematic diagram of a terminal structure according to another embodiment of the present invention;

[0038] Figure 3 is a schematic diagram of a terminal structure according to another embodiment of the present invention;

[0039] Figure 4 is a schematic diagram of a terminal structure according to another embodiment of the present invention;

[0040] Figure 5 A schematic diagram of one of the steps in the method for preparing a terminal structure according to a specific embodiment of the present invention;

[0041] Figure 6 A schematic diagram of one of the steps in the method for preparing a terminal structure according to a specific embodiment of the present invention;

[0042] Figure 7 A schematic diagram of one of the steps in the method for preparing a terminal structure according to a specific embodiment of the present invention;

[0043] Figure 8 A schematic diagram of one of the steps in the method for preparing a terminal structure according to a specific embodiment of the present invention;

[0044] Fig. 9 A schematic diagram of one of the steps in the method for preparing a terminal structure according to a specific embodiment of the present invention;

[0045] Fig.10 A schematic diagram of one of the steps in the method for preparing a terminal structure according to a specific embodiment of the present invention;

[0046] Fig.11 A schematic diagram of one of the steps in the method for preparing a terminal structure according to a specific embodiment of the present invention;

[0047] Fig.12 FIG. 4 is a schematic diagram of a terminal structure according to another embodiment of the present invention.

[0048] Reference numerals:

[0049] 100: terminal structure;

[0050] 1: epitaxial layer of the first conductivity type; 2: substrate; 20: ion concentration adjustment region of the second conductivity type; 12: doped column of the second conductivity type; 23: first junction terminal extension structure; 4: main junction; 5: second junction terminal extension structure; 6: third junction terminal extension structure; 22: field limiting ring structure; 21: lateral variable doping structure; 14: trench stop ring; 3: doped base region of the second conductivity type; 8: emitter; 9: oxide layer; 10: metal stop ring; 11: collector; 7: doped stop ring of the first conductivity type; 16: doped stop ring of the second conductivity type; 17: stop ring of the first conductivity type. DETAILED DESCRIPTION

[0051] Embodiments of the present invention are described in detail below. The embodiments described with reference to the accompanying drawings are exemplary. Embodiments of the present invention are described in detail below.

[0052] In order to solve the above problems, a first embodiment of the present invention proposes a terminal structure, which can improve the voltage resistance and reduce the risk of premature breakdown of the terminal structure.

[0053] Reference below Figure 1 The terminal structure of the embodiment of the present invention is described as follows: Figure 1 As shown, the terminal structure 100 includes a substrate 2, an epitaxial layer 1 of a first conductivity type, an ion concentration adjustment region 20 of a second conductivity type, and at least one doping column 12 of the second conductivity type.

[0054] Among them, an epitaxial layer 1 of the first conductivity type grows on a substrate 2 in a first direction perpendicular to the substrate; an ion concentration adjustment region 20 of the second conductivity type is located in the epitaxial layer 1 and close to the upper surface of the epitaxial layer 1; a doped column 12 of the second conductivity type is located in the epitaxial layer 1 and close to the upper surface of the epitaxial layer 1, and at least part of the doped column 12 is located in the adjustment region.

[0055] Here, the first conductivity type may be N type, and the second conductivity type may be P. Optionally, the substrate 2 may be an N type doped substrate, and the doping concentration of the N type doped substrate is 4×10 14 cm -3 , the doping concentration of the N-type doped epitaxial layer 1 is 4×10 13 cm -3 , the thickness of the epitaxial layer 1 is 90 μm.

[0056] In the actual use of the terminal structure, when the terminal structure is externally biased, the holes in the ion concentration adjustment zone of the second conductivity type will be completely depleted, leaving only immovable negative charges, which makes the direction of the electric field formed by the part of the ion concentration adjustment zone of the second conductivity type connected to its external voltage opposite to the original electric field direction. These immovable negative charges make the depletion region of the part connected to the external voltage of the ion concentration adjustment zone expand outward, increasing the radius of curvature of the part connected to the external voltage of the ion concentration adjustment zone, thereby reducing the electric field of the part connected to the external voltage of the ion concentration adjustment zone. However, the withstand voltage of the power device is very sensitive to the dose and interface state of the ion concentration adjustment zone of the second conductivity type. It is a great challenge to accurately control the ion dose injected into the ion concentration adjustment zone of the second conductivity type in the process. When the ion implantation dose of the ion concentration adjustment zone is low, there are not enough immovable negative charges in the ion concentration adjustment zone to offset the electric field in the original direction, so it will break down in advance near the part connected to the external voltage of the ion concentration adjustment zone. Therefore, in order to solve the above problems, the terminal structure 100 of the present application is provided with at least one doping column 12 in the epitaxial layer 1 and close to the upper surface of the epitaxial layer 1, and part of the doping column 12 is provided in the ion concentration adjustment zone 20. Thus, the dosage window of the ion concentration adjustment zone of the second conductive type is designed to become wider, so that the total amount of injected charge of the doping column 12 of the second conductive type and the ion concentration adjustment zone 20 of the second conductive type can provide sufficient negative charge to attract the electric field directed to the part connected to the external voltage of the ion concentration adjustment zone. That is to say, the electric field is adjusted based on the introduced doping column 12 of the second conductive type. When the ion dose of the ion concentration adjustment zone is low, even if the ion concentration adjustment zone does not have enough immovable negative charge to offset the electric field in the original direction, the doping column can provide sufficient negative charge to attract the electric field, thereby achieving the purpose of sharing the electric field, improving the voltage resistance, and reducing the risk of premature breakdown of the terminal structure.

[0057] According to the terminal structure 100 of the present invention, at least one doping column 12 is arranged in the epitaxial layer 1 and close to the upper surface of the epitaxial layer 1, and part of the doping column 12 is arranged in the ion concentration adjustment area 20. Therefore, when the ion dosage of the ion concentration adjustment area 20 is low, even if the ion concentration adjustment area 20 does not have enough immovable negative charges to offset the electric field in the original direction, the doping column 12 can provide enough negative charges to attract the electric field, thereby achieving the purpose of sharing the electric field, improving the voltage resistance, and reducing the risk of premature breakdown of the terminal structure 100.

[0058] According to some embodiments of the present invention, the terminal structure 100 includes a main junction 4, which is located in the epitaxial layer 1 and close to the upper surface of the epitaxial layer 1, and the main junction and the ion concentration adjustment region 20 are arranged along a second direction parallel to the substrate; the doped column is located on one side of the ion concentration adjustment region close to the main junction. The doped column can prevent the main junction 4 from being broken down prematurely.

[0059] In some embodiments, reference Figure 2 As shown, the ion concentration adjustment region 20 includes a first junction terminal extension structure 23, namely a JTE region 23. In the second direction, the first junction terminal extension structure 23 contacts the main junction 4, and the second conductive type doped column 12 is located in the first junction terminal extension structure 23 and close to the main junction 4.

[0060] Specifically, the JTE region 23 may be a single-region JTE structure, such as Figure 2 As shown, the JTE region 23 has two electric field peaks, one on the main junction surface and the other on the curved junction at the end of the JTE region. If the ion implantation dose of the JTE region 23 is too small, the JTE region 23 will be depleted prematurely, the main junction will not be effectively protected, and breakdown will occur on the main junction surface. Therefore, by introducing the doped column 12 in the JTE region 23, such as the doped column 12 is arranged on the left side of the JTE region 23, the JTE region 23 will be prevented from being depleted prematurely, and more negative charges can be provided after depletion to share the electric field of the main junction, thereby improving its voltage resistance and widening the process window.

[0061] In some embodiments, since the breakdown voltage of a single JTE region is very sensitive to the JTE dose (dose = concentration / depth), once the optimal JTE dose is deviated, its performance will drop sharply, which requires precise control of the injected JTE dose in the process, otherwise the withstand voltage of the device will change significantly. In order to reduce the sensitivity of the breakdown voltage of a single JTE region to the JTE dose, a dual-region JTE structure is proposed, that is, the JTE region 23 includes a first JTE region 5 and a second JTE region 6, such as Figure 1 Therefore, based on the fact that the modulation capability of the surface electric field of the dual-zone or multi-zone JTE is stronger than that of the single-zone JTE, and the dual-zone or multi-zone JTE can improve the withstand voltage of the terminal better than the single-zone JTE, the dual-zone JTE structure adopted in the present application can effectively widen the JTE dose window.

[0062] In some embodiments, Figure 1 As shown, the ion concentration adjustment region 20 includes a second junction terminal extension structure 5 and a third junction terminal extension structure 6. In the second direction, the second junction terminal extension structure and the third junction terminal extension structure are both in contact with the main junction, and the third junction terminal extension structure surrounds the bottom surface of the second junction terminal extension structure and the side surface of the second junction terminal extension structure away from the main junction, that is, the second JTE region 5 is formed on the third JTE region 6. The doped column is located in the second junction terminal extension structure and close to the main junction.

[0063] Specifically, considering that at high doses, such as when the dose of the second JTE region is much greater than the dose of the third JTE region, the second TE region cannot largely share the electric field of the second JTE region, resulting in a very high peak value of the electric field at the end of the second JTE region. The second JTE region 5 is formed on the third JTE region 6 to form a stepped JTE terminal structure. The stepped JTE terminal structure can alleviate the electric field at the end of the second JTE region 5 at high doses and increase the JTE dose window. The stepped JTE terminal structure is particularly effective in improving the withstand voltage at high doses.

[0064] However, due to the weak ability of the JTE region to alleviate the electric field at the edge of the main junction at a low dose, the device breaks down prematurely due to excessive electric field strength at the edge of the main junction. At the same time, the terminal structure needs to produce step-type masks of different thicknesses, so that there is no need to use different injection energies to achieve the injection depth, that is, a step-type JTE region can be formed by a single injection of energy, but this mask is difficult to control in terms of process. Generally, a cutoff ring is used at the tail of the terminal to prevent the depletion region from being depleted to the dicing track. The distance between the depletion region and the cutoff ring must be long enough to avoid leakage, which will result in a longer terminal length, a larger chip area used, and higher costs. In addition, excessive terminal length will also increase leakage current. Therefore, in order to solve the above problems, the terminal structure 100 of the present application uses two different JTE doses to form a dual-zone JTE, namely the second JTE zone 5 and the third JTE zone 6, so that when there is a dose deviation, the electric field distribution of the entire terminal structure can be made more uniform, the JTE dose window is increased, and the wider the JTE dose window, the lower the sensitivity of the terminal structure to the JTE dose, and the process does not need to accurately control the JTE dose, which reduces the process requirements and makes the process easier to implement. In addition, the terminal structure 100 does not need to be implemented using a special mask process, and the process is simple.

[0065] In addition, in the embodiment, the present application sets the second conductive type doping column 12 to be located in the second JTE region 5, referring to Figure 1 As shown, two doping columns 12 are introduced on the left side of the second JTE region 5. When the concentration of the JTE region is relatively low, the doping columns 12 can play a role in regulating the electric field at the edge of the main junction, thereby reducing the electric field at the main junction when the JTE dose is relatively low and alleviating the high electric field near the main junction.

[0066] According to some embodiments of the present invention, Figure 1 As shown, the doping thickness of the second JTE region 5 is less than the doping thickness of the third JTE region 6, and along the second direction, the length of the second JTE region 5 is less than the length of the third JTE region 6; and / or, the doping concentration of the second JTE region 5 is higher than the doping concentration of the third JTE region 6. Preferably, the doping concentration of the JTE region is in the order of 12 to 13.

[0067] According to some embodiments of the present invention, the doping concentration of the second JTE region 5 is C2, wherein C2 satisfies: 6×10 12 cm -3 ≤C2≤8×10 13 cm -3 With such configuration, the doping concentration of the second JTE region 5 is appropriate, which can satisfy both the device withstand voltage requirements for the JTE dosage and interface state, and the charge requirements.

[0068] According to some embodiments of the present invention, the doping concentration of the third JTE region 6 is C3, wherein C3 satisfies: 2×10 12 cm -3 ≤C3≤6×10 13 cm -3 With such configuration, the doping concentration of the third JTE region 6 is appropriate, which can satisfy both the device withstand voltage requirements for the JTE dosage and interface state, and the charge requirements.

[0069] According to some embodiments of the present invention, reference Figure 3 As shown, the ion concentration adjustment region 20 may include a lateral variable doping structure 21, in which the lateral variable doping structure is in contact with the main junction in the second direction, and the thickness of the lateral variable doping structure in the first direction gradually decreases from one end close to the main junction to an end away from the main junction; the doping column is located in the lateral variable doping structure and close to the main junction.

[0070] That is to say, the present application changes the JTE uniform doping area of ​​the lateral variable doping structure 21 area into a non-uniform distribution, which can be regarded as a combination of countless small JTE areas with different charge amounts, which is similar to the withstand voltage principle of the JTE area. When the ion implantation dose of the lateral variable doping structure 21 is low, the amount of charge injected into the lateral variable doping structure 21 near the main junction cannot provide enough negative charge, and the light doping at the end of the lateral variable doping structure 21 can reduce the peak electric field of the curved junction, which will break down in advance near the main junction 4 area. Therefore, by introducing a high-doping column 12 near the main junction, the total amount of injected charge near the main junction 4 can provide enough negative charge to attract the electric field pointing to the main junction, thereby improving the withstand voltage capability, and the light doping at the end of the lateral variable doping structure 21 can also better reduce the peak electric field, prevent premature breakdown, and reduce the requirements for the process.

[0071] According to some embodiments of the present invention, reference Figure 1 As shown, there can be multiple doped columns 12 of the second conductivity type, and the multiple doped columns all extend along a first direction perpendicular to the substrate, and the multiple doped columns are arranged at intervals along the second direction. In this way, the ability of the doped columns 12 to adjust the electric field can be improved by increasing the number of doped columns 12.

[0072] In some embodiments, when the ion concentration adjustment region 20 is in a higher JTE dose range, as the number of the second conductivity type doping columns 12 increases, the closer to the edge of the ion concentration adjustment region 20, the electric field concentration effect will appear at the edge of the last second conductivity type doping column, thereby affecting the breakdown voltage of the device; and considering that when the ion concentration adjustment region 20 is in a low JTE dose range, the more the number of the second conductivity type doping columns 12, the better, but the situation in the medium JTE dose range must also be taken into account, therefore, preferably, the number of the doping columns 12 is 2 or 3.

[0073] According to some embodiments of the present invention, reference Figure 1 As shown, the widths of the multiple second conductivity type doped columns along the second direction are the same. Such an arrangement is convenient for operation and has a low process difficulty. It is also convenient to adjust the number of the second conductivity type doped columns in combination with the width of the second conductivity type doped columns.

[0074] It should be noted that the larger the width of the doped column of the second conductivity type, the larger the terminal area occupied, especially when the doped columns of the second conductivity type are all located inside the ion concentration adjustment zone, which means that the terminal length occupied by the doped columns of the second conductivity type is fixed. The larger the width of the doped column of the second conductivity type, the fewer the number of doped columns of the second conductivity type, and the lower the ability to adjust the electric field. Therefore, the width of the doped column of the second conductivity type should be appropriately selected.

[0075] It should be noted that the reference Figure 1 As shown, the width of each doped column 12 is consistent, and the larger the width of the doped column 12, the larger the terminal area it occupies. Since the doped columns 12 are all located inside the first JTE region 5, this means that the terminal length occupied by the doped columns 12 is fixed, and the larger the width of the doped columns 12, the fewer the number of doped columns 12, and the lower the ability to adjust the electric field, so the width of the doped columns 12 should be appropriately selected.

[0076] In an embodiment, the doping concentration and depth of the doping column 12 are consistent with the main junction 4, that is, the doping column 12 and the main junction 4 can be formed simultaneously, for example, by simultaneously injecting boron ions, and the doping concentration can be on the order of 14.

[0077] According to some embodiments of the present invention, reference Figure 4 As shown, the ion concentration adjustment region includes at least one field limiting ring structure 22, at least one of the field limiting ring structures and the main junction are arranged at intervals in the second direction, part of the second conductive type doped columns 12 are located in the field limiting ring structure 22, and in the second direction, the doped columns are close to the side of the field limiting ring structure close to the main junction.

[0078] According to some embodiments of the present invention, reference Figure 4 As shown, there are multiple field limiting ring structures 22, and the multiple field limiting ring structures 22 are arranged at intervals along the second direction. The multiple doped columns are arranged corresponding to the multiple field limiting ring structures, and a portion of each doped column is located in the corresponding field limiting ring structure.

[0079] That is, as shown in the figure, a doped column 12 is added to the left side of each field limiting ring structure 22, and the ion implantation dose of the field limiting ring structure 22 is lower than the ion implantation dose of the doped column 12. The field limiting ring structure 22 can maintain a relatively larger breakdown voltage by using a lower dose, because the low-concentration field limiting ring structure 22 will allow the depletion region to expand wider toward the surface, and the surface electric field will increase, while the introduction of a high-concentration doped column 12 can increase the surface concentration and prevent the surface electric field from being too large. Therefore, when the concentration of the field limiting ring structure 22 is slightly lower, the doped column 12 can provide more negative charges after depletion, share the electric field of the main junction and the previous field limiting ring structure 22, and thus improve its withstand voltage capability.

[0080] According to some embodiments of the present invention, reference Figure 1-Figure 3 As shown, when the ion concentration adjustment region 20 includes the JTE region 23 or the lateral doping structure 21 , the JTE region 23 or the lateral doping structure 21 is in contact with the main junction 4 , and the second conductivity type doping column 12 is spaced apart from the main junction 4 .

[0081] According to some embodiments of the present invention, reference Figure 4 As shown, when the ion concentration adjustment region 20 includes the field limiting ring structure 22 , the ion concentration adjustment region 20 is spaced apart from the main junction 4 .

[0082] According to some embodiments of the present invention, the distance between the doped column closest to the main junction among the multiple doped columns and the main junction can be set to d1. Specifically, as shown in the figure, the multiple doped columns of the second conductivity type are arranged along the first direction from the side of the ion concentration adjustment region 20 close to the main junction, wherein the first doped column of the second conductivity type close to the main junction is the first doped column of the second conductivity type, and the spacing between the first doped column of the second conductivity type and the main junction 4 is d1, wherein d1 satisfies: 4μm≤d1≤5μm.

[0083] Specifically, if d1 is less than 4μm, the distance between the first doped column of the second conductivity type and the main junction is small, and the first doped column of the second conductivity type is very close to the main junction. At a lower reverse bias, a punch-through may occur between the two, thereby enhancing the electric field concentration effect at the edge of the doped column of the second conductivity type; if d1 is greater than 5μm, the farther the first doped column of the second conductivity type is from the main junction, the weaker the ability of the doped column of the second conductivity type to share the electric field at the main junction. Therefore, considering the influence of the distance between the first doped column of the second conductivity type and the main junction 4 on the breakdown voltage of the device, the present application reasonably sets d1 to satisfy 4μm≤d1≤5μm, thereby taking into account the electric field concentration effect and the ability to share the electric field. Optionally, d1 is 4μm, 4.1μm, 4.2μm, 4.3μm, 4.4μm, 4.5μm, 4.6μm, 4.7μm, 4.8μm, 4.9μm or 5.0μm. But not limited to this.

[0084] According to some embodiments of the present invention, the second conductivity type doped column is a heavily doped column. The second conductivity type doped column is formed by implanting boron ions, and the boron ion doping dose of the second conductivity type doped column is on the order of 14.

[0085] According to some embodiments of the present invention, the main junction is a heavily doped main junction. The main junction is formed by implanting boron ions, and the boron ion doping dose of the main junction is on the order of 14.

[0086] According to some embodiments of the present invention, the doping concentration of the second conductivity type doped column and the main junction is the same. In this way, the doping concentration of the second conductivity type doped column and the main junction is the same, which is conducive to promoting the doping column of the second conductivity type to balance the electric field.

[0087] According to some embodiments of the present invention, the doping concentration of the second conductivity type doping column and the doping concentration of the main junction are C1, where C1 satisfies: 2×10 14 cm -3 ≤C1≤6×10 14 cm -3 With such arrangement, the doping concentrations of the second conductivity type doping column and the main junction are appropriate, the regulating effect on the electric field is stronger, and the cost is lower.

[0088] According to some embodiments of the present invention, Figure 1-Figure 4 As shown, the terminal structure 100 further includes a trench stop ring 14 and a filling material. In the second direction, the main junction, the ion concentration adjustment region and the trench stop ring are arranged at intervals.

[0089] Among them, along the second direction, the trench stop ring 14 is located in the epitaxial layer 1 and close to the upper surface of the epitaxial layer 1; in the first direction, the trench stop ring 14 is located on the right side of the ion concentration adjustment area 20 and is spaced apart from the ion concentration adjustment area 20; the filling material is located in the trench stop ring. Such a setting adopts a stop ring to prevent the depletion region from being consumed to the scribe line, and uses a deep groove to cut off the depletion layer to affect the surface electric field distribution, thereby preventing the depletion region from being consumed to the scribe line to form a leakage channel, and at the same time, it can reduce the width of the terminal area, occupy a smaller chip, and save costs.

[0090] According to some embodiments of the present invention, the filling material is polysilicon, or the filling material is SiO2 or a low dielectric constant insulating medium, so as to ensure the insulation effect.

[0091] In some embodiments, as shown in the figure, the trench stop ring 14 is located at the rightmost side of the epitaxial layer 1, and the depth of the trench stop ring 14 is greater than or equal to the depth of the depletion layer where the trench stop ring 14 is located. The material in the trench stop ring 14 is polysilicon poly Si, preferably N-type heavily doped polysilicon, and the entire trench can be filled by deposition.

[0092] According to some embodiments of the present invention, Figure 1-Figure 4 As shown, the terminal structure 100 includes a first conductivity type doped stop ring 7 , which is located on the outer surface of the side wall and the outer surface of the bottom wall of the trench stop ring 14 .

[0093] According to some embodiments of the present invention, Fig.12 As shown, when the filling material is SiO 2 or a low dielectric constant insulating medium, the terminal structure 100 includes a second conductivity type doped stop ring 16 and a first conductivity type doped stop ring 17 .

[0094] Among them, the doped cut-off ring 16 of the second conductivity type is located on the outer surface of the side wall and the outer surface of the bottom wall of the trench cut-off ring 14; the cut-off ring 17 of the first conductivity type is located in the epitaxial layer and close to the upper surface of the epitaxial layer. In the second direction, the cut-off ring of the first conductivity type is located on the side of the doped cut-off ring away from the ion concentration adjustment area and is spaced from the doped cut-off ring. Thus, by using a cut-off ring at the rightmost end of the terminal structure to prevent the depletion region from being consumed to the scribe path, and adding a trench cut-off ring at the end of the terminal, the deep groove is used to cut off the depletion layer to affect the surface electric field distribution, and the depletion region is prevented from being exhausted to the scribe path to form a leakage channel. At the same time, the width of the terminal area can be reduced, the chip occupied is smaller, and the cost is saved.

[0095] According to some embodiments of the present invention, Figure 1-Figure 4As shown, the terminal structure 100 further includes a doped base region 3 of the second conductivity type, a collector 11 , an emitter 8 , an oxide layer 9 and a metal stop ring 10 .

[0096] Among them, the doped base region 3 of the second conductivity type is located on the side of the substrate 2 away from the epitaxial layer 1 of the first conductivity type; the collector 11 is located on the side of the doped base region 3 of the second conductivity type away from the substrate 2; the emitter 8 is located on the upper surface of the epitaxial layer 1 of the first conductivity type, and in the first direction, is located at the left end of the epitaxial layer 1 of the first conductivity type, and is in contact with the main junction 4; the oxide layer 9 is formed on the upper surface of the epitaxial layer 1 of the first conductivity type, and in the first direction, one end of the oxide layer 9 extends to the emitter 8, and the other end extends to be flush with the epitaxial layer 1 of the first conductivity type; the metal stop ring 10 is located on the upper surface of the oxide layer 9, and in the first direction is located at one end of the oxide layer 9 corresponding to the trench stop ring, for example, in the figure, it is located at the right end of the oxide layer 9.

[0097] According to some embodiments of the present invention, the substrate is a Si substrate or a SiC substrate; and / or the substrate is a high-concentration doped substrate of the first conductivity type.

[0098] According to some embodiments of the present invention, the doping concentration of the substrate of the first conductivity type is C4, wherein C4 satisfies: 2×10 14 cm -3 ≤C3≤6×10 14 cm -3 .

[0099] According to some embodiments of the present invention, the doping concentration of the epitaxial layer of the first conductivity type is C5, wherein C5 satisfies: 2×10 13 cm -3 ≤C5≤6×10 13 cm -3 ; and / or the thickness of the epitaxial layer of the first conductivity type is m1, wherein m1 satisfies: 80μm≤m1≤100μm.

[0100] According to some embodiments of the present invention, the first conductivity type is N-type, and the second conductivity type is P-type; or the first conductivity type is P-type, and the second conductivity type is N-type.

[0101] According to some embodiments of the present invention, the thickness of the oxide layer is m2, wherein m2 satisfies: 0.5μm≤m2≤1μm; and / or the thickness of the emitter is m3, wherein m3 satisfies: 3μm≤m3≤4μm; and / or the thickness of the metal cutoff ring is m4, wherein m4 satisfies: 3μm≤m4≤4μm; and / or the thickness of the collector is m5, wherein m5 satisfies: 1.2μm≤m5≤1.3μm.

[0102] In some embodiments, the collector is a multilayer metallization structure, for example, the multilayer metallization structure includes Al, Ti, Ni and Ag. The use of a multilayer metallization structure can not only reduce the thermal mechanical stress of the chip and improve its thermal characteristics, but also obtain a low ohmic contact resistance. The total thickness of the multilayer metallization structure is preferably 1.2 to 1.3 μm. The oxide layer can be formed by deposition, and its material can be SiO2 or BPSG (boron phosphorus silicon glass). The emitter and the metal cutoff ring can be metals or alloys, and the preparation method is sputtering and alloying Alloy, preferably aluminum-copper alloy AlSi or AlSiCu.

[0103] A second aspect of the present invention provides a method for preparing a terminal structure, comprising the following steps:

[0104] Step S1, providing a substrate of a first conductivity type, and preparing an epitaxial layer of the first conductivity type on the substrate along a first direction perpendicular to the substrate.

[0105] Step S2, preparing a second conductivity type ion concentration adjustment region and at least one second conductivity type doping column on the epitaxial layer, wherein the ion concentration adjustment region is located in the epitaxial layer and close to the upper surface of the epitaxial layer, the doping column is located in the epitaxial layer and close to the upper surface of the epitaxial layer, and at least part of the doping column is located in the ion concentration adjustment region.

[0106] The following is an example of the preparation method using the ion concentration adjustment region including the first JTE region and the second JTE region as an example. Specifically, first, at a doping concentration of 4×10 14 cm -3 The epitaxial growth is 90 μm on the Si substrate 2 and the doping concentration is 4×10 13 cm -3 The N-type drift region, i.e., the epitaxial layer 1, is formed, and then an oxide mask 15 is grown on the surface. A photoresist is then spin-coated on the mask 15. Finally, the mask on the designated drift region is removed by a photolithography process, and a multi-step P-type ion implantation is performed on the region not protected by the mask, thereby forming a second JTE region 6, as shown in FIG. Figure 5 Then, the photoresist is removed, and then a mask 15 is grown on the surface of the N-type epitaxial drift region 1, and then a photoresist is applied to the mask 15, and then a higher dose of P-type ion implantation is performed after exposure and development, thereby forming a first JTE1 region 5, as shown Figure 6 As shown; Figure 6 A mask 15 is continuously grown on the surface of the structure shown in the figure, and then a photolithography process is performed to form a Figure 7 The mask shape shown in the figure is then used to perform high-dose P-type ion implantation to simultaneously form highly doped doped columns.

[0107] According to the preparation method of an embodiment of the present invention, by setting at least one doping column in the epitaxial layer and close to the upper surface of the epitaxial layer, and part of the doping column is set in the ion concentration adjustment area, when the ion concentration in the ion concentration adjustment area is low, even if the ion concentration adjustment area does not have enough immovable negative charges to offset the electric field in the original direction, the doping column can provide enough negative charges to attract the electric field, thereby achieving the purpose of sharing the electric field, improving the voltage resistance, and reducing the risk of premature breakdown of the terminal structure.

[0108] According to some embodiments of the present invention, the preparation method also includes: preparing a main junction on the epitaxial layer, wherein the main junction is located in the epitaxial layer and close to the upper surface of the epitaxial layer, and the main junction and the ion concentration adjustment region are spaced apart along a second direction parallel to the substrate. For example, in the figure, the main junction is located on the left side of the ion concentration adjustment region.

[0109] According to some embodiments of the present invention, the preparation method also includes: preparing a trench stop ring on the epitaxial layer, wherein, along the second direction, the trench stop ring is located in the epitaxial layer and close to the upper surface of the epitaxial layer, and in the second direction, the trench stop ring is located on the side of the ion concentration adjustment region away from the main junction and is spaced apart from the ion concentration adjustment region.

[0110] Specifically, refer to Figure 8 As shown, after the preparation of the doped column and the trench stop ring is completed, a new photomask is prepared, the trench is etched by ion reactive etching technology, and a polysilicon medium containing doped ions, i.e., a filling material, is deposited in the trench by chemical vapor deposition, and the excess polysilicon is removed by chemical mechanical polishing technology to finally form a trench stop ring 14; then, a photoresist is coated on the surface of the epitaxial layer 1, exposed and developed, and N-type ion implantation and high-temperature well-driving processes are performed in sequence to diffuse the doped ions to the bottom and side of the trench stop ring 14, forming an N-type doped stop ring, i.e., a second conductive type doped stop ring 7, as shown in FIG. Fig. 9 shown.

[0111] According to some embodiments of the present invention, the preparation method also includes: along the first direction, preparing a second conductive type doped base region and a collector on a side of the substrate away from the first conductive type epitaxial layer, the second conductive type doped base region is located on the side of the substrate away from the first conductive type epitaxial layer, and the collector is located on the side of the second conductive type doped base region away from the substrate; along the second direction, preparing an emitter, an oxide layer and a metal stop ring on the upper surface of the substrate, respectively, wherein the emitter is located on the upper surface of the first conductive type epitaxial layer, and in the second direction, is located at the left end of the first conductive type epitaxial layer and is in contact with the main junction; the oxide layer is formed on the upper surface of the first conductive type epitaxial layer, and in the first direction, one end of the oxide layer extends to the emitter, and the other end extends to be flush with the first conductive type epitaxial layer; the metal stop ring is located on the upper surface of the oxide layer, and in the first direction, one end of the trench stop ring corresponding to the oxide layer is close to the oxide layer, for example, in the figure, is located on the right end of the oxide layer.

[0112] Specifically, refer to Fig.10 and Fig.11 As shown, after the trench stop ring is prepared, an oxide layer 9 with a thickness of 0.5μm to 1μm is deposited, which has the function of passivating the protection device and isolating the metal electrode, and then 3μm to 4μm of AlSi or AlSiCu alloy is sputtered on the front side to form an emitter 8 and a metal stop ring 10; finally, the substrate 2 is thinned, and P-type ions are implanted on the back side of the substrate 2 to form a P-type doped region, that is, a second conductive type doped base region 3, followed by laser annealing or furnace annealing to activate impurities and repair the lattice, and then Al / Ti / Ni / Ag four-layer metal with a total thickness of 1.2μm to 1.3μm is evaporated to form a back collector 11. The multi-layer metalization structure can not only reduce the thermal mechanical stress of the chip and improve its thermal characteristics, but also reduce the ohmic contact resistance.

[0113] A third aspect of the present invention provides an electronic device, comprising at least one terminal structure of the above-mentioned embodiment.

[0114] According to the electronic device of the embodiment of the present invention, by adopting the terminal structure of the above embodiment, the voltage resistance can be improved and the risk of premature breakdown of the terminal structure can be reduced.

[0115] A fourth aspect of the present invention provides a vehicle, comprising the electronic device of the above embodiment.

[0116] According to the vehicle of the embodiment of the present invention, the pressure resistance can be improved and the risk of premature breakdown of the terminal structure can be reduced by adopting the electronic device of the above embodiment.

[0117] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example.

[0118] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A terminal structure, characterized in that: include: substrate; An epitaxial layer of a first conductivity type, the epitaxial layer being located on the substrate in a first direction perpendicular to the substrate; An ion concentration adjustment region of a second conductivity type, the ion concentration adjustment region being located in the epitaxial layer and close to an upper surface of the epitaxial layer; At least one doped column of the second conductivity type is located in the epitaxial layer and close to the upper surface of the epitaxial layer, and at least a portion of the doped column is located in the ion concentration adjustment region.

2. The terminal structure according to claim 1, characterized in that: The terminal structure comprises: A main junction, the main junction is located in the epitaxial layer and close to the upper surface of the epitaxial layer, the main junction and the ion concentration adjustment region are arranged along a second direction parallel to the substrate; The doping column is located on a side of the ion concentration adjustment region close to the main junction.

3. The terminal structure according to claim 2, characterized in that: The ion concentration adjustment area comprises: A first junction terminal extension structure is provided. In the second direction, the first junction terminal extension structure is in contact with the main junction. The doped column is located in the first junction terminal extension structure and close to the main junction.

4. The terminal structure according to claim 2, characterized in that: The ion concentration adjustment area comprises: A second junction terminal extension structure and a third junction terminal extension structure, both of which are in contact with the main junction in the second direction, and the third junction terminal extension structure surrounds the bottom surface of the second junction terminal extension structure and the side surface of the second junction terminal extension structure away from the main junction.

5. The terminal structure according to claim 4, characterized in that: The doped column is located within the second junction termination extension structure and is proximate to the main junction.

6. The terminal structure according to claim 4, characterized in that: The doping concentration of the second junction termination extension structure is higher than the doping concentration of the third junction termination extension structure.

7. The terminal structure according to claim 2, characterized in that: The ion concentration adjustment area comprises: a lateral variable doping structure, wherein in the second direction, the lateral variable doping structure is in contact with the main junction, and a thickness of the lateral variable doping structure in the first direction gradually decreases from an end close to the main junction to an end far from the main junction; The doped column is located in the lateral doping variation structure and is close to the main junction.

8. The terminal structure according to claim 3, 5 or 7, characterized in that: The terminal structure includes a plurality of doped columns, each of which extends along a first direction perpendicular to the substrate, and the plurality of doped columns are arranged at intervals along the second direction.

9. The terminal structure according to claim 7, characterized in that: The number of the doped columns is N, wherein N satisfies: 2≤N≤3.

10. The terminal structure according to claim 7, characterized in that: The widths of the plurality of doped columns along the second direction are the same.

11. The terminal structure according to claim 2, characterized in that: The ion concentration adjustment area comprises: At least one field limiting ring structure, at least one field limiting ring structure and the main junction are arranged at intervals in the second direction, part of the doped column is located in the field limiting ring structure, and in the second direction, the doped column is close to a side of the field limiting ring structure close to the main junction.

12. The terminal structure according to claim 11, characterized in that: The ion concentration adjustment area comprises: A plurality of the field limiting ring structures are arranged at intervals in the second direction.

13. The terminal structure according to claim 12, characterized in that: The terminal structure comprises: The plurality of doped columns are arranged corresponding to the plurality of field limiting ring structures, and a portion of each doped column is located within the corresponding field limiting ring structure.

14. The terminal structure according to claim 13, characterized in that: The distance between the doped column closest to the main junction among the plurality of doped columns and the main junction is d1, wherein d1 satisfies: 4 μm≤d1≤5 μm.

15. The terminal structure according to any one of claims 2 to 14, characterized in that: The terminal structure also includes: A trench stop ring is located in the epitaxial layer and close to the upper surface of the epitaxial layer. The trench stop ring is filled with a filling material. In the second direction, the main junction, the ion concentration adjustment region and the trench stop ring are arranged at intervals.

16. The terminal structure according to claim 15, characterized in that: The terminal structure also includes: A doped stop ring of a second conductivity type, wherein the doped stop ring of the second conductivity type surrounds the side surface and the bottom surface of the trench stop ring; A cut-off ring of a first conductivity type is located in the epitaxial layer and close to an upper surface of the epitaxial layer. In the second direction, the cut-off ring of the first conductivity type is located on a side of the doped cut-off ring away from the ion concentration adjustment region and is spaced apart from the doped cut-off ring.

17. The terminal structure according to claim 15, characterized in that: The terminal structure also includes: A doped base region of a second conductivity type, wherein the doped base region of the second conductivity type is located on a side of the substrate away from the epitaxial layer of the first conductivity type; a collector, the collector being located at a side of the second conductivity type doped base region away from the substrate; An emitter, the emitter being located on an upper surface of the epitaxial layer of the first conductivity type and contacting the main junction; an oxide layer, the oxide layer being formed on the upper surface of the epitaxial layer of the first conductivity type, wherein in the first direction, one end of the oxide layer extends to the emitter, and the other end extends to be flush with the epitaxial layer of the first conductivity type; A metal stop ring is located on the upper surface of the oxide layer and in the second direction, at an end of the oxide layer corresponding to the trench stop ring.

18. A method for preparing a terminal structure, characterized in that: The steps include: providing a substrate of a first conductivity type; Preparing an epitaxial layer of a first conductivity type on the substrate along a first direction perpendicular to the substrate; An ion concentration adjustment region of the second conductivity type and at least one doped column of the second conductivity type are prepared on the epitaxial layer, wherein the ion concentration adjustment region is located in the epitaxial layer and close to the upper surface of the epitaxial layer, the doped column is located in the epitaxial layer and close to the upper surface of the epitaxial layer, and at least part of the doped column is located in the ion concentration adjustment region.

19. The preparation method according to claim 18, characterized in that: The preparation method further comprises: A main junction is prepared on the epitaxial layer, wherein the main junction is located in the epitaxial layer and close to the upper surface of the epitaxial layer, and along a second direction parallel to the substrate, the main junction and the ion concentration adjustment region are arranged at intervals.

20. The preparation method according to claim 19, characterized in that: The preparation method further comprises: A trench stop ring is prepared on the epitaxial layer, wherein the trench stop ring is located in the epitaxial layer and close to the upper surface of the epitaxial layer, and in the second direction, the trench stop ring is located on the side of the ion concentration adjustment region away from the main junction and is spaced apart from the ion concentration adjustment region.

21. The preparation method according to claim 20, characterized in that: The preparation method further comprises: Along the first direction, a doped base region and a collector electrode of a second conductivity type are respectively prepared on a side of the substrate away from the epitaxial layer of the first conductivity type, wherein the doped base region of the second conductivity type is located on a side of the substrate away from the epitaxial layer of the first conductivity type, and the collector electrode is located on a side of the doped base region of the second conductivity type away from the substrate; Along the first direction, an emitter, an oxide layer and a metal stop ring are respectively prepared on the upper surface of the substrate, wherein the emitter is located on the upper surface of the epitaxial layer of the first conductivity type, and in the second direction, is located at the left end of the epitaxial layer of the first conductivity type and is in contact with the main junction, the oxide layer is formed on the upper surface of the epitaxial layer of the first conductivity type, and in the first direction, one end of the oxide layer extends to the emitter, and the other end extends to be flush with the epitaxial layer of the first conductivity type; the metal stop ring is located on the upper surface of the oxide layer, and in the first direction, is close to one end of the oxide layer corresponding to the trench stop ring.

22. An electronic device, characterized in that: Comprising at least one terminal structure according to any one of claims 1 to 17.

23. A vehicle, characterized in that: An electronic device comprising the electronic device described in claim 22.

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