Bidirectional dtscr structure and electrostatic protection device

Abstract

The application provides a bidirectional DTSCR structure and an electrostatic protection device, relates to the technical field of semiconductors, and solves the problem of poor electrostatic discharge capacity of an electrostatic protection device in the prior art. The bidirectional DTSCR structure can make the ESD current of the electrostatic protection device not need to bypass the STI, the distance between the anode and the cathode of the device is the shortest, the on-resistance is effectively reduced, and the discharge capacity of the device is improved.

Description

Technical Field

[0001] This application relates to the field of semiconductor technology, and in particular to a bidirectional DTSCR structure and an electrostatic discharge protection device. Background Technology

[0002] With the miniaturization and high-density development of chips, the requirements for electrostatic discharge (ESD) protection in chip protection are becoming increasingly stringent. Diode-triggered silicon controlled rectifiers (DTSCRs), as devices used for ESD protection, are widely used in low-voltage processes due to their low trigger voltage, small area, and low capacitance. However, the discharge capability of related technologies for thyristor devices is reduced. When ESD protection is required to discharge ESD current, the device's turn-on speed is slow, making it difficult to meet the chip's ESD requirements. Summary of the Invention

[0003] This application provides a bidirectional DTSCR structure and an electrostatic discharge protection device, which solves the problem of poor electrostatic discharge capability of electrostatic discharge protection devices in related technologies. The bidirectional DTSCR structure of this solution enables the ESD current to flow around the STI during discharge, and the distance between the anode and cathode of the device is minimized, effectively reducing the on-resistance and improving the discharge capability of the device.

[0004] In one aspect, this application provides a bidirectional DTSCR structure, which includes a P-type substrate layer, an N-type deep well layer, and a barrier layer.

[0005] The N-type deep well layer is located on the P-type substrate layer. The N-type deep well layer includes adjacent N-type well regions and P-type well regions, and shallow trenches surrounding the N-type well regions are formed on the surface of the N-type deep well layer. The N-type well region includes a first P+ implantation region, a first N+ implantation region, and a second P+ implantation region arranged sequentially and spaced apart along a first direction. The first P+ implantation region is used to connect to the cathode, and the second P+ implantation region is used to connect to the anode. The P-type well region includes a second N+ implantation region, a third P+ implantation region, and a third N+ implantation region arranged sequentially and spaced apart along the first direction. The second N+ implantation region is spaced apart from the first P+ implantation region along a second direction. The second N+ implantation region is used to connect to the anode, and the third P+ implantation region is connected to the first N+ implantation region through a metal wire layer. The third N+ implantation region is used to connect to the cathode. A barrier layer is disposed on the surface of the N-type well region and the P-type well region. The barrier layer is used to form an isolation region between the first P+ injection region, the first N+ injection region, the second P+ injection region, the second N+ injection region, the third P+ injection region, and the third N+ injection region.

[0006] Secondly, this application also provides an electrostatic discharge protection device, which includes the bidirectional DTSCR structure as described in the first aspect above.

[0007] The bidirectional DTSCR structure of this application can form a discharge path between the first P+ injection region and the second N+ injection region spaced apart in the second direction, and also between the second P+ injection region and the third N+ injection region. With multiple ESD discharge paths, the discharge capability of the device is improved. Compared with the long path that needs to cross multiple injection regions and shallow trenches in related technologies, this solution can provide a shorter discharge path and a shorter anode-cathode spacing, which effectively reduces the on-resistance of the device, helps to improve the device's resistance to ESD failure, and improves robustness. Attached Figure Description

[0008] Figure 1 This is a partial cross-sectional schematic diagram of a silicon controlled rectifier (SCR) device related to this technology.

[0009] Figure 2 for Figure 1 The top view of the thyristor device shown.

[0010] Figure 3 This is a top view of a bidirectional DTSCR structure provided in an embodiment of this application.

[0011] Figure 4 for Figure 3 A-A' cross-sectional view of the bidirectional DTSCR structure.

[0012] Figure 5 for Figure 3 B-B' cross-sectional view of the bidirectional DTSCR structure.

[0013] Figure 6 for Figure 3 C-C' cross-sectional view of the bidirectional DTSCR structure.

[0014] Figure 7 for Figure 3 D-D' cross-sectional view of the bidirectional DTSCR structure.

[0015] Figure 8 for Figure 3 E-E' cross-sectional view of the bidirectional DTSCR structure.

[0016] Figure 9 This is a schematic diagram of the discharge path of the bidirectional DTSCR structure in the forward operating condition of this application.

[0017] Figure 10 This is a schematic diagram of the discharge path of the bidirectional DTSCR structure in reverse operation.

[0018] Figure 11This is a schematic diagram of the metal wire layout of an electrostatic protection device provided in an embodiment of this application. Detailed Implementation

[0019] The embodiments of this application will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely illustrative of the embodiments of this application and are not intended to limit the scope of this application. Furthermore, it should be noted that, for ease of description, the accompanying drawings only show the parts related to the embodiments of this application, not all structures. Those skilled in the art, after reading this specification, should be able to conceive that any combination of technical features can constitute an optional implementation method, provided that the technical features do not contradict each other.

[0020] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects, not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class, not limited in number; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship. In the description of this application, "multiple" means two or more, and "several" means one or more.

[0021] Diode-triggered silicon controlled rectifiers (DTSCRs), used for ESD protection, are widely used in low-voltage processes due to their low trigger voltage, small area, and low capacitance. In practical applications, the inventors discovered that the DTSCRs of this technology form an arrangement of multiple different types of injection regions, with shallow trench isolation (STI) separating the different injection regions. Figure 1 This is a partial cross-sectional schematic diagram of a silicon controlled rectifier (SCR) device based on related technologies. Figure 2 for Figure 1 The top view of the thyristor device shown is for reference. Figure 1 and Figure 2 Each injection region (P+ and N+ in the figure) forms an elongated region on the N-well and P-well, and the injection regions are isolated from each other by shallow trenches. The two P+ injection regions on the N-well serve as the anode and cathode, respectively, and the two N+ injection regions on the P-well serve as the cathode and anode, respectively. Figure 2In the figure, S1 represents the forward anode-cathode spacing, and S2 represents the reverse anode-cathode spacing. It can be seen that when electrostatic protection is required to discharge ESD current, the ESD current needs to bypass the shallow trench to form a long discharge path (as shown by S1 and S2 in the figure). This long path results in a large parasitic capacitance and on-resistance on the device, which in turn reduces the device's discharge capability and slows down the device's turn-on speed, making it difficult to meet the chip's electrostatic discharge requirements.

[0022] In response, this application provides a bidirectional DTSCR structure and an electrostatic discharge protection device. By utilizing the active region to remove the shallow trench isolation layer and by isolating the anode and cathode active regions through the barrier layer, the anode and cathode layout on the bidirectional DTSCR structure is optimized, effectively reducing the anode-cathode spacing, lowering the on-resistance of the bidirectional DTSCR structure, and thus improving robustness.

[0023] In one embodiment, the bidirectional DTSCR structure includes a P-type substrate layer, an N-type deep well layer, and a barrier layer, wherein the N-type deep well layer is located on the P-type substrate layer, such as being formed on the surface of the P-type substrate layer by a deposition process. Furthermore, the N-type deep well layer includes adjacent N-type well regions and P-type well regions; that is, the N-type well regions and P-type well regions are structures within the N-type deep well layer, adjacent to each other on the layout, with their sides touching. It can be understood that a well region is a specific conductive region formed in a semiconductor material through a doping process, and the N-type well region and P-type well region correspond to regions formed by different ion doping. Shallow trenches surrounding the N-type well regions and P-type well regions are provided on the surface of the N-type deep well layer. It can be understood that in the bidirectional DTSCR structure, a region including the N-type well region and the P-type well region is formed by the shallow trenches, and corresponding implantation regions (such as P+ implantation regions and N+ implantation regions) are formed within this region.

[0024] Furthermore, the N-type well region includes a first P+ injection region, a first N+ injection region, and a second P+ injection region arranged sequentially and spaced apart along a first direction. The P-type well region includes a second N+ injection region, a third P+ injection region, and a third N+ injection region arranged sequentially and spaced apart along the first direction, with the second N+ injection region and the first P+ injection region arranged spaced apart along a second direction. The first and second directions are different directions; optionally, in some embodiments, the first and second directions are perpendicular to each other. The first P+ injection region is used to connect to the cathode, the second P+ injection region is used to connect to the anode, the second N+ injection region is used to connect to the anode, the third P+ injection region is connected to the first N+ injection region via a metal wire layer, and the third N+ injection region is used to connect to the cathode. That is, in the first direction, the first N+ injection region and the third P+ injection region located in the middle are connected to each other, such as through a metal wire layer located above the injection region, while the other injection regions located on both sides serve as anodes and cathodes, such as the first P+ injection region and the third N+ injection region both serving as cathodes, and the second P+ injection region and the second N+ injection region both serving as anodes.

[0025] It should be noted that multiple injection areas in the same direction can be located on the same horizontal line or the same vertical line, or they can be allowed to offset within a preset angle range in that direction. For example, if the offset of one injection area relative to other injection areas in one direction is within that angle range, the two injection areas are in the same direction.

[0026] Furthermore, a barrier layer is disposed on the surfaces of the N-type well region and the P-type well region. The barrier layer serves to form an isolation region between the first P+ injection region, the first N+ injection region, the second P+ injection region, the second N+ injection region, the third P+ injection region, and the third N+ injection region. As a structure deposited on the N-type deep well layer, this barrier layer is located in the region formed by the shallow trench surrounding the N-type well region and the P-type well region, and covers the surfaces of the N-type well region and the P-type well region on the N-type deep well layer in this region. However, it does not cover the first P+ injection region, the first N+ injection region, the second P+ injection region, the second N+ injection region, the third P+ injection region, and the third N+ injection region, thereby forming isolation between the injection regions.

[0027] Understandably, when the bidirectional DTSCR structure is operating in the forward direction, and an ESD current is applied to the DTSCR anode (i.e., the second P+ injection region) and the cathode (i.e., the third N+ injection region) is grounded, the diode trigger path, consisting of the second P+ injection region (anode), the N-type well region, the first N+ injection region, the third P+ injection region (short-circuited to the first N+ injection region), the P-type well region, and the third N+ injection region (cathode), first conducts and discharges the ESD current. As the ESD current increases, the diode trigger path provides trigger current for the parasitic PNP and parasitic NPN, causing the parasitic PNP and parasitic NPN to enter a positive feedback state, resulting in the complete conduction of the discharge path formed by the second P+ injection region (anode), the N-type well region, the P-type well region, and the third N+ injection region (cathode). When the bidirectional DTSCR structure operates in reverse, when ESD current is applied to the DTSCR cathode (i.e., the first P+ injection region) and the anode (i.e., the second N+ injection region) is grounded, the diode trigger path, consisting of the first P+ injection region (cathode), the N-type well region, the first N+ injection region, the third P+ injection region shorted to the first N+ injection region, the P-type well region, and the second N+ injection region (anode), first conducts and discharges the ESD current. As the ESD current increases, the diode trigger path provides trigger current for the parasitic PNP and parasitic NPN, causing the parasitic PNP and parasitic NPN to enter a positive feedback state, resulting in the complete conduction of the discharge path formed by the first P+ injection region (cathode), the N-type well region, the P-type well region, and the second N+ injection region (anode).

[0028] As can be seen from the above scheme, a discharge path can be formed between the first P+ injection region and the second N+ injection region spaced apart in the second direction, and a discharge path can also be formed between the second P+ injection region and the third N+ injection region. There are multiple ESD discharge paths, which improves the discharge capability of the device. Compared with the long path that needs to cross multiple injection regions and shallow trenches in related technologies, this scheme can provide a shorter discharge path and a shorter anode-cathode spacing, which effectively reduces the on-resistance of the device, helps to improve the device's ESD resistance and improves its robustness.

[0029] In one embodiment, in the second direction, the spacing between the first P+ injection region and the second N+ injection region, the spacing between the first N+ injection region and the third P+ injection region, and the spacing between the second P+ injection region and the third N+ injection region are all first distances, which are greater than or equal to 3 micrometers and less than or equal to 5 micrometers. Accordingly, the anode-cathode spacing corresponding to the discharge path is equal to the first distance, i.e., the anode-cathode spacing is greater than or equal to 3 micrometers and less than or equal to 5 micrometers. The reduced spacing shortens the discharge path and lowers the resistance, thereby enabling it to withstand and discharge larger ESD currents. Furthermore, this bidirectional DTSCR structure only has PN junction capacitance, making it suitable for low-voltage, high-speed applications below 1.4V.

[0030] Optionally, the spacing between the first P+ injection region and the second N+ injection region, the spacing between the first N+ injection region and the third P+ injection region, and the spacing between the second P+ injection region and the third N+ injection region are within the range of 3-5 μm, that is, the values ​​of each first distance can be the same or different.

[0031] In some embodiments, in the first direction, the spacing between the first P+ injection region and the first N+ injection region, the spacing between the first N+ injection region and the second P+ injection region, the spacing between the second N+ injection region and the third P+ injection region, and the spacing between the third P+ injection region and the third N+ injection region are all second distances, which are greater than or equal to 3 micrometers and less than or equal to 5 micrometers. It is understood that in the first direction, the length of each injection region on the bidirectional DTSCR structure does not affect the device's ESD resistance. This can be addressed by adjusting the spacing between the injection regions in the first direction, such as setting the distance to be greater than or equal to 3 micrometers and less than or equal to 5 micrometers. Compared to the length of each injection region in related technologies, the bidirectional DTSCR structure of this solution has a shorter distance from the first P+ injection region to the second P+ injection region in the first direction, resulting in a smaller area of ​​the bidirectional DTSCR structure and contributing to device miniaturization.

[0032] In some embodiments, the inner edge of the shallow trench serves as one side surrounding the N-type well region or the P-type well region. This inner edge of the shallow trench corresponds to the edge of a first region, which is a region on the surface of the N-type deep well layer formed by the outer edges of the first P+ injection region, the first N+ injection region, the second P+ injection region, the second N+ injection region, the third P+ injection region, and the third N+ injection region. Optionally, the first region is a rectangular region. The shallow trench is positioned around the region formed by each injection region to isolate the different injection regions.

[0033] In one embodiment, the second direction is perpendicular to the first direction, the third P+ injection region and the first N+ injection region are spaced apart along the second direction, and the third N+ injection region and the second P+ injection region are spaced apart along the second direction. For example, the injection regions are parallel and perpendicular to each other to form an array layout. Figure 3 This is a top view of a bidirectional DTSCR structure provided in an embodiment of this application. Figure 4 for Figure 3 A-A' section view of the bidirectional DTSCR structure, refer to Figure 3 and Figure 4The figure shows the arrangement of the implantation regions on the device. Shallow trenches 210 are arranged around the N-type well region and the P-type well region to isolate the device, and the substrate layer 110 is located below. An N-type well region 121 and a P-type well region 122 are formed in an N-type deep well layer 120, and each injection region is arranged thereon in an array. In the first direction, the first P+ injection region 1211, the first N+ injection region 1212 and the second P+ injection region 1213 are arranged alternately, and the second N+ injection region 1214, the third P+ injection region 1215 and the third N+ injection region 1216 are arranged alternately. In the second direction, the first P+ injection region 1211 and the second N+ injection region 1214 are arranged alternately, the first N+ injection region 1212 and the third P+ injection region 1215 are arranged alternately, and the second P+ injection region 1213 and the third N+ injection region 1216 are arranged alternately. The first N+ injection region 1212 and the third P+ injection region 1215 are connected by a line in the figure. Furthermore, each implantation region is isolated from the other by a barrier layer 130. Optionally, the barrier layer 130 is a silicide block (SAB), which is a silicide block composed of one or more of silicon oxide (SiO2), silicon nitride (Si3N4), or silicon oxynitride (SiON) deposited to isolate each implantation region.

[0034] Figure 5 for Figure 3 B-B' cross-section of the bidirectional DTSCR structure. Figure 6 for Figure 3 C-C' cross-section of the bidirectional DTSCR structure. Figure 7 for Figure 3 D-D' cross-section of the bidirectional DTSCR structure. Figure 8 for Figure 3 Cross-sectional view of the bidirectional DTSCR structure along line E-E'. Referring to the forward operation of the bidirectional DTSCR structure... Figure 5-8 ,like Figure 6 and Figure 7 As shown, after the ESD current is applied to the second P+ injection region 1213, which serves as the anode, it flows to the N-type well region 121, as... Figure 5 As shown, since both the second P+ injection region 1213 and the first N+ injection region 1212 are located in the N-type well region 121, the ESD current flows to the first N+ injection region 1212 and enters the third P+ injection region 1215, which is short-circuited to the first N+ injection region 1212, as... Figure 8As shown, both the third P+ injection region 1215 and the third N+ injection region 1216 are located in the P-type well region 122. Current then flows to the P-type well region 122 and enters the third N+ injection region 1216, which is also located in the P-type well region 122. The current completes the forward flow from the anode to the cathode, and the bidirectional DTSCR forward diode path is turned on. As the ESD pulse current further increases, it triggers the parasitic PNP and NPN on it to enter a positive feedback state, forming a shorter discharge path between the second P+ injection region 1213 and the third N+ injection region 1216. That is, the discharge path formed by the second P+ injection region 1213, the N-type well region 121, the P-type well region 122, and the third N+ injection region 1216 is fully connected, as shown in the diagram. Figure 9 As shown, Figure 9 This diagram illustrates the discharge path of the bidirectional DTSCR structure under forward operation. Arrowed line segments L1 and L2 represent the discharge path, with the arrows indicating the direction of current flow. L1 corresponds to the path through the second P+ injection region 1213, the N-type well region 121, the first N+ injection region 1212, the third P+ injection region 1215 (short-circuited to the first N+ injection region 1212), the P-type well region 122, and the third N+ injection region 1216. L2 corresponds to the path through the second P+ injection region 1213, the N-type well region 121, the P-type well region 122, and the third N+ injection region 1216.

[0035] In the case of the bidirectional DTSCR structure operating in reverse, refer to Figure 4-5 as well as Figure 7-8 ,like Figure 4 and Figure 7 As shown, after the ESD current is applied to the first P+ injection region 1211, which serves as the cathode, it flows to the N-type well region 121, as... Figure 5 As shown, since both the first P+ injection region 1211 and the first N+ injection region 1212 are located in the N-type well region 121, the ESD current flows to the first N+ injection region 1212 and enters the third P+ injection region 1215, which is short-circuited to the first N+ injection region 1212, as... Figure 8 As shown, the third P+ injection region 1215 and the second N+ injection region 1214 are both located in the P-type well region 122. The current then flows to the P-type well region 122 and enters the second N+ injection region 1214, which is also located in the P-type well region 122. The current completes the reverse flow from the cathode to the anode, and the bidirectional DTSCR reverse diode path is turned on. As the ESD pulse current further increases, it triggers the parasitic PNP and parasitic NPN on it to enter the positive feedback state, so as to form a shorter discharge path between the first P+ injection region 1211 and the second N+ injection region 1214. That is, the discharge path formed by the first P+ injection region 1211, the N-type well region 121, the P-type well region 122 and the second N+ injection region 1214 is fully turned on, and the corresponding path is as follows. Figure 10 As shown, Figure 10This diagram illustrates the discharge path of the bidirectional DTSCR structure in reverse operation. The discharge path is represented by arrowed line segments L3 and L4, with the arrows indicating the direction of current flow. L3 corresponds to the path through the first P+ injection region 1211, the N-type well region 121, the first N+ injection region 1212, the third P+ injection region 1215 (short-circuited to the first N+ injection region 1212), the P-type well region 122, and the second N+ injection region 1214. L4 corresponds to the path through the first P+ injection region 1211, the N-type well region 121, the P-type well region 122, and the second N+ injection region 1214.

[0036] The bidirectional DTSCR structure of this solution has multiple ESD discharge paths, which improves the device's discharge capability. Compared with the long paths that need to cross multiple injection regions and shallow trenches in related technologies, this bidirectional DTSCR structure can provide shorter discharge paths and shorter anode-cathode spacing, effectively reducing the device's on-resistance, which helps to improve the device's ESD resistance and robustness.

[0037] This application also provides an electrostatic discharge protection device, which includes the bidirectional DTSCR structure provided in the above embodiments. This structure optimizes the anode and cathode layout on the bidirectional DTSCR structure by removing the shallow trench isolation layer using the active region and isolating the anode and cathode active regions through the barrier layer. This effectively reduces the anode and cathode spacing, lowers the on-resistance of the bidirectional DTSCR structure, helps improve the device's ESD resistance and robustness.

[0038] In some embodiments, the electrostatic discharge protection device further includes a first anode metal wire, a second anode metal wire, and a cathode metal wire, such as Figure 11 As shown, Figure 11 This is a schematic diagram of the metal wire layout of an electrostatic discharge (ESD) protection device according to an embodiment of this application. The first anode metal wire 310 connects to the second P+ injection region in the bidirectional DTSCR structure, the second anode metal wire 320 connects to the second N+ injection region in the bidirectional DTSCR structure, and the cathode metal wire 330 connects to the first P+ injection region and the third N+ injection region in the bidirectional DTSCR structure. The metal wires are represented by dashed lines in the diagram. Furthermore, the first anode metal wire 310, the second anode metal wire 320, and the cathode metal wire 330 are parallel to each other and are all inclined along a predetermined direction. This predetermined direction is related to the arrangement direction corresponding to the first P+ injection region and the third N+ injection region. That is, the metal wires adopt an oblique layout to connect the corresponding injection regions, thereby serving as corresponding electrodes. By optimizing the layout of the metal wires corresponding to each electrode, the ESD protection device can improve the uniformity of current distribution, which is beneficial for reducing parasitic capacitance and optimizing wiring efficiency.

[0039] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0040] Note that the above are merely preferred embodiments and the technical principles employed in this application. Those skilled in the art will understand that this application is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the scope of protection of this application. Therefore, although this application has been described in detail through the above embodiments, this application is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of this application, the scope of which is determined by the scope of the appended claims.

Claims

1. A bidirectional DTSCR structure, comprising a P-type substrate layer, characterized in that, Also includes: An N-type deep well layer is located on the P-type substrate layer. The N-type deep well layer includes adjacent N-type well regions and P-type well regions, and shallow trenches surrounding the N-type well regions and the P-type well regions are provided on the surface of the N-type deep well layer. The N-type well region includes a first P+ injection region, a first N+ injection region, and a second P+ injection region that are sequentially spaced apart along a first direction. The first P+ injection region is used to connect to the cathode, and the second P+ injection region is used to connect to the anode. The P-type well region includes a second N+ injection region, a third P+ injection region, and a third N+ injection region arranged sequentially and spaced apart along a first direction. The second N+ injection region and the first P+ injection region are arranged spaced apart along a second direction. The second N+ injection region is used to connect to the anode. The third P+ injection region and the first N+ injection region are used to connect through a metal wire layer. The third N+ injection region is used to connect to the cathode. A barrier layer is disposed on the surfaces of the N-type well region and the P-type well region, and the barrier layer is used to form an isolation region between the first P+ injection region, the first N+ injection region, the second P+ injection region, the second N+ injection region, the third P+ injection region, and the third N+ injection region.

2. The bidirectional DTSCR structure according to claim 1, characterized in that, In the second direction, the spacing between the first P+ injection region and the second N+ injection region, the spacing between the first N+ injection region and the third P+ injection region, and the spacing between the second P+ injection region and the third N+ injection region are all first distances, and the first distance is greater than or equal to 3 micrometers and less than or equal to 5 micrometers.

3. The bidirectional DTSCR structure according to claim 2, characterized in that, In the first direction, the spacing between the first P+ injection region and the first N+ injection region, the spacing between the first N+ injection region and the second P+ injection region, the spacing between the second N+ injection region and the third P+ injection region, and the spacing between the third P+ injection region and the third N+ injection region are all second distances, and the second distance is greater than or equal to 3 micrometers and less than or equal to 5 micrometers.

4. The bidirectional DTSCR structure according to any one of claims 1-3, characterized in that, The second direction is perpendicular to the first direction, the third P+ injection region and the first N+ injection region are spaced apart along the second direction, and the third N+ injection region and the second P+ injection region are spaced apart along the second direction.

5. The bidirectional DTSCR structure according to claim 1, characterized in that, The inner edge of the shallow trench corresponds to the edge of the first region, which is the area formed on the surface of the N-type deep well layer by the outer edges corresponding to the first P+ injection region, the first N+ injection region, the second P+ injection region, the second N+ injection region, the third P+ injection region, and the third N+ injection region.

6. The bidirectional DTSCR structure according to claim 5, characterized in that, The first region is a rectangular region.

7. The bidirectional DTSCR structure according to claim 1, characterized in that, The barrier layer is a silicide barrier layer.

8. An electrostatic discharge protection device, characterized in that, Includes the bidirectional DTSCR structure as described in any one of claims 1-7.

9. The electrostatic discharge protection device according to claim 8, characterized in that, It also includes a first anode metal wire, a second anode metal wire, and a cathode metal wire. The first anode metal wire is connected to the second P+ injection region in the bidirectional DTSCR structure, the second anode metal wire is connected to the second N+ injection region in the bidirectional DTSCR structure, and the cathode metal wire is connected to the first P+ injection region and the third N+ injection region in the bidirectional DTSCR structure. The first anode metal wire, the second anode metal wire, and the cathode metal wire are parallel to each other and are all inclined along a preset direction, which is the arrangement direction in which the cathode metal wire connects the first P+ injection region and the third N+ injection region.

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