An electrostatic protection device with a bidirectional SCR path

Abstract

The present invention provides an electrostatic protection device with a bidirectional SCR path, comprising N bidirectional BJT series stacking units and M bidirectional SCR series stacking units connected in series, the bidirectional BJT series stacking unit is connected to the positive electrode of the electrostatic protection device, the bidirectional SCR series stacking unit is connected to the negative electrode of the electrostatic protection device, the bidirectional SCR series stacking unit is provided with a first P-type ESD protection layer and a second P-type ESD protection layer, the first P-type ESD protection layer is provided with a P+ heavily doped active region and an N+ heavily doped active region connected to the bidirectional BJT series stacking unit, the second P-type ESD protection layer is provided with an N+ heavily doped active region and a P+ heavily doped active region connected to the negative electrode of the electrostatic protection device, and a bidirectional SCR path is formed between the first P-type ESD protection layer and the second P-type ESD protection layer. The beneficial effects of the present invention are: the bidirectional SCR path can reduce the clamping voltage Vc of the electrostatic protection device.

Description

Technical Field

[0001] The invention relates to the technical field of electrostatic protection, and in particular to an electrostatic protection device with a bidirectional SCR path. Background Art

[0002] Electrostatic protection devices are protective devices that prevent various electrical components from being burned by static electricity. Silicon Controlled Rectifier (SCR) is a new type of electrostatic discharge (ESD) protection device. The biggest feature of SCR is that it has a very strong discharge capacity and can provide a lower clamping voltage (Vc) for the circuit.

[0003] ESD protection devices can provide ESD protection for circuits or chips. When the voltage surge or spike in the protected circuit exceeds the turn-on voltage of the protection device, the device can clamp the voltage and provide a low impedance path for the ESD (Electro-Staticdischarge) current, thereby protecting the circuit from damage by the voltage spike. Clamping voltage (Vc) is a key performance indicator of the protection device. Only when the ESD high voltage is clamped within a safe voltage range can the protection device protect the normal operation of the circuit. If the Vc of the ESD protection device exceeds the safety value of the protected circuit, the protection device is likely to lose its protective function, causing the risk of electronic circuit failure, failure and damage.

[0004] For applications such as automotive electronics or fast charging power supplies, the operating voltage of the chip is usually in the high-voltage field such as 12V / 18V / 24V / 48V, which requires the DC withstand voltage of the ESD protection circuit to be improved accordingly. In addition, when there is an inductive load on the I / O port, its actual operating voltage still has a negative voltage situation, which requires the ESD protection circuit to have the ability of "high withstand voltage, bidirectional discharge", and the design difficulty is very high. In order to meet the electrostatic protection requirements of the above applications, researchers generally use low-voltage bidirectional BJT (Bipolar Junction Transistor) devices with strong robustness for series stacking. However, with this solution, as the number of stacks increases, the on-resistance under bidirectional bias will deteriorate exponentially, and Vc will increase dramatically, as shown in Figures 1 (a), 1 (b) and 1 (c), which will eventually seriously deteriorate the effective electrostatic protection capability, and will also bring about problems such as huge layout area and increased manufacturing cost. Among them, the I / O port is the link between the host and the controlled object for information exchange, and the host exchanges data with external devices through the I / O port.

[0005] Figures 1(a), 1(b) and 1(c) respectively show the stacking schematic diagram, the structural diagram and the IV curve schematic diagram of the existing bidirectional BJT stacking solution. The existing bidirectional BJT stacking solution is to stack multiple bidirectional BJT modules in series. The disadvantage of this stacking solution is that as the number of stacks increases, the on-resistance also increases proportionally, and Vc will increase significantly. Figure 1(b) is a structural diagram of a bidirectional planar PNP stacking device with the number N=3. The electrostatic discharge path of I / O1→I / O2 and I / O2→I / O1 is a bidirectional PNP path. As shown in Figure 1(c), as the number of stacks increases, Vc increases significantly, which can easily exceed the safety voltage of the protected circuit, thereby losing the protection effect on the electronic circuit. Summary of the invention

[0006] In order to solve the problems in the prior art, the present invention provides an electrostatic protection device with a bidirectional SCR path. A new type of bidirectional electrostatic protection stacking architecture is formed by adding a bidirectional SCR series stacking unit with hysteresis characteristics in series to a traditional bidirectional BJT series stacking unit. The bidirectional SCR path of the bidirectional SCR series stacking unit can reduce the overall clamping voltage Vc of the electrostatic protection device. While providing bidirectional electrostatic protection for the I / O port, adjusting the ratio of the number of bidirectional SCR series stacking units and the bidirectional BJT series stacking units can change the overall clamping voltage Vc of the electrostatic protection device. While maintaining the linear stacking of the working voltage of the electrostatic protection device, the overall clamping voltage of the electrostatic protection device can be flexibly adjusted. The design has high freedom and no latch-up risk, significantly improves the effective electrostatic protection level of the chip, has a wide range of applications, and is particularly suitable for circuit protection with a wide working voltage range such as automotive electronic chips and high-voltage charging power chips, thereby solving the problem in the prior art that the traditional bidirectional BJT stacking method will cause a higher Vc and occupy a huge layout area.

[0007] The present invention provides an electrostatic protection device with a bidirectional SCR path, comprising a semiconductor substrate and N bidirectional BJT series stacked units and M bidirectional SCR series stacked units arranged on the semiconductor substrate, N and M are both positive integers, the bidirectional BJT series stacked units are connected in series with the bidirectional SCR series stacked units through metal interconnects, the bidirectional BJT series stacked units are connected to the positive electrode of the electrostatic protection device through the metal interconnects, the bidirectional SCR series stacked units are connected to the negative electrode of the electrostatic protection device through the metal interconnects, the bidirectional SCR series stacked units are provided with a first N-type well region, the first N-type well region is provided with a first P-type ESD protection layer and a second P-type ESD protection layer, the first P-type ESD protection layer is provided with a path A P+ heavily doped active area and an N+ heavily doped active area are connected to the bidirectional BJT series stack unit through metal interconnection lines, and the second P-type ESD protection layer is provided with an N+ heavily doped active area and a P+ heavily doped active area connected to the negative electrode of the electrostatic protection device through metal interconnection lines. A bidirectional SCR path with hysteresis characteristics is formed between the P+ heavily doped active area and the N+ heavily doped active area of ​​the first P-type ESD protection layer and the P+ heavily doped active area and the N+ heavily doped active area of ​​the second P-type ESD protection layer. The bidirectional SCR path can reduce the overall clamping voltage Vc of the electrostatic protection device, and adjusting the ratio of the number of the bidirectional SCR series stack unit and the bidirectional BJT series stack unit can change the overall clamping voltage Vc of the electrostatic protection device.

[0008] The present invention is further improved in that the number N of the bidirectional BJT series stacked units is less than the number M of the bidirectional SCR series stacked units.

[0009] The present invention is further improved, the distance between the P+ heavily doped active area and the N+ heavily doped active area of ​​the first P-type ESD protection layer, and the distance between the P+ heavily doped active area and the N+ heavily doped active area of ​​the second P-type ESD protection layer are both L1, L1≥0μm, and adjusting the size of L1 can adjust the hysteresis depth of the bidirectional SCR path.

[0010] The present invention is further improved in that the dividing area ratio of the P+ heavily doped active area and the N+ heavily doped active area of ​​the first P-type ESD protection layer and the dividing area ratio of the P+ heavily doped active area and the N+ heavily doped active area of ​​the second P-type ESD protection layer can be adjusted.

[0011] The present invention is further improved, and a second N-type well region is provided in the bidirectional BJT series stack unit, and a P+ heavily doped active region is provided in the second N-type well region, which is connected to the bidirectional SCR series stack unit through a metal interconnection line, and a P+ heavily doped active region is also provided in the second N-type well region, which is connected to the positive electrode of the electrostatic protection device through a metal interconnection line.

[0012] The present invention is further improved, the positive pole of the electrostatic protection device is connected to I / O port one, the negative pole of the electrostatic protection device is connected to I / O port two, and the semiconductor substrate is also provided with multiple electrostatic protection rings, and the electrostatic protection rings are grounded P+ heavily doped active areas.

[0013] The present invention is further improved, the positive pole of the electrostatic protection device is connected to the I / O port, the negative pole of the electrostatic protection device is grounded, and the semiconductor substrate is also provided with a plurality of electrostatic protection rings, and the electrostatic protection rings include a grounded P+ heavily doped active area and an N+ heavily doped active area connected to a power supply.

[0014] The present invention is further improved, the bidirectional BJT series stack unit is transformed from a planar metal oxide semiconductor field effect transistor or a planar bipolar junction transistor or a vertical bipolar junction transistor, and the bidirectional SCR series stack unit is a bidirectional silicon controlled rectifier.

[0015] The present invention is further improved, and the manufacturing process of the electrostatic protection device with a bidirectional SCR path includes a nano-scale complementary metal oxide semiconductor process, a three-dimensional fin field effect transistor, a full-surround gate transistor process or a silicon process on an insulating substrate.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: an electrostatic protection device with a bidirectional SCR path is provided, and a new bidirectional electrostatic protection stacking architecture is formed by adding a bidirectional SCR series stacking unit with hysteresis characteristics in series to a traditional bidirectional BJT series stacking unit. The bidirectional SCR path of the bidirectional SCR series stacking unit can reduce the overall clamping voltage Vc of the electrostatic protection device. While providing bidirectional electrostatic protection for the I / O port, adjusting the ratio of the number of bidirectional SCR series stacking units and bidirectional BJT series stacking units can change the overall clamping voltage Vc of the electrostatic protection device. While maintaining the linear stacking of the working voltage of the electrostatic protection device, the overall clamping voltage of the electrostatic protection device can be flexibly adjusted. The design has a high degree of freedom and no latch-up risk, and the effective electrostatic protection level of the chip is significantly improved. The application range is wide, and it is particularly suitable for circuit protection with a wide working voltage range such as automotive electronic chips and high-voltage charging power chips, which solves the problem in the prior art that the traditional bidirectional BJT stacking method will cause a higher Vc and occupy a huge layout area. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the solutions in the present invention or the prior art, a brief introduction is given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0018] FIG1 (a) is a schematic diagram of a stacking scheme of an existing bidirectional BJT stacking solution;

[0019] FIG1( b ) is a structural diagram of an existing bidirectional BJT stacking solution;

[0020] FIG1( c ) is a schematic diagram of the IV curve of the existing bidirectional BJT stacking solution;

[0021] FIG2 (a) is a schematic diagram of a stack of an electrostatic protection device with a bidirectional SCR path according to the present invention;

[0022] FIG2( b ) is a schematic diagram of an IV curve of an electrostatic protection device having a bidirectional SCR path according to the present invention;

[0023] Figure 3 A structural schematic diagram of an electrostatic protection device with a bidirectional SCR path according to the present invention;

[0024] FIG4 (a) is a schematic diagram of the layout of a bidirectional SCR series stacked unit of the present invention;

[0025] FIG4( b ) is a structural cross-sectional view of the bidirectional SCR series stacked unit of the present invention along the AA′ tangent line;

[0026] FIG4( c ) is a structural cross-sectional view of the bidirectional SCR series stacked unit of the present invention along the BB′ cut line. DETAILED DESCRIPTION

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present invention belongs; the terms used in the specification of the application herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention; the terms "including" and "having" and any variations thereof in the specification and claims of the present invention and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of the present invention or the above-mentioned drawings are used to distinguish different objects, not to describe a specific order.

[0028] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present invention. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0029] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings.

[0030] As shown in Figures 1(a) to 4(c), the present invention provides an electrostatic protection device with a bidirectional SCR path, comprising a semiconductor substrate and N bidirectional BJT series stacking units and M bidirectional SCR series stacking units arranged on the semiconductor substrate, where N and M are both positive integers, the bidirectional BJT series stacking units are connected in series with the bidirectional SCR series stacking units through metal interconnections, the bidirectional BJT series stacking units are connected to the positive electrode of the electrostatic protection device through the metal interconnections, the bidirectional SCR series stacking units are connected to the negative electrode of the electrostatic protection device through the metal interconnections, a first N-type well region is provided in the bidirectional SCR series stacking unit, a first P-type ESD protection layer and a second P-type ESD protection layer are provided in the first N-type well region, a P+ heavily doped active region and an N+ heavily doped active region connected to the bidirectional BJT series stacking unit through the metal interconnections, and an N+ heavily doped active region and a P+ heavily doped active region connected to the negative electrode of the electrostatic protection device through the metal interconnections are provided in the second P-type ESD protection layer. In this embodiment, a bidirectional SCR path with hysteresis characteristics is formed between the P+ heavily doped active area and the N+ heavily doped active area of ​​the first P-type ESD protection layer and the P+ heavily doped active area and the N+ heavily doped active area of ​​the second P-type ESD protection layer, that is, an SCR path with hysteresis characteristics is formed between the P+ heavily doped active area of ​​the first P-type ESD protection layer and the N+ heavily doped active area of ​​the second P-type ESD protection layer, and an SCR path with hysteresis characteristics is also formed between the N+ heavily doped active area of ​​the first P-type ESD protection layer and the P+ heavily doped active area of ​​the second P-type ESD protection layer. R path, the bidirectional SCR path can reduce the overall clamping voltage Vc of the ESD protection device. Adjusting the ratio of the number of bidirectional SCR series stacking units and the number of bidirectional BJT series stacking units can change the overall clamping voltage Vc of the ESD protection device. While maintaining the linear stacking of the ESD protection device working voltage, the overall clamping voltage of the ESD protection device can be flexibly adjusted. It has a high degree of design freedom and no latch-up risk, which significantly improves the effective ESD protection level of the chip and has a wide range of applications, especially for circuit protection with a wide working voltage range such as automotive electronic chips and high-voltage charging power chips.

[0031] As shown in Figures 2 (a) to 4 (c), the number N of bidirectional BJT series stacked units is less than the number M of bidirectional SCR series stacked units. The distance between the P+ heavily doped active area and the N+ heavily doped active area of ​​the first P-type ESD protection layer, and the distance between the P+ heavily doped active area and the N+ heavily doped active area of ​​the second P-type ESD protection layer are both L1, L1 ≥ 0 μm. Adjusting the size of L1 can adjust the hysteresis depth of the bidirectional SCR path. The segmentation area ratio of the P+ heavily doped active area and the N+ heavily doped active area of ​​the first P-type ESD protection layer, and the P+ heavily doped active area of ​​the second P-type ESD protection layer are The divided area ratio of the N+ heavily doped active area and the N+ heavily doped active area can be adjusted; a second N-type well area is provided in the bidirectional BJT series stack unit, a P+ heavily doped active area connected to the bidirectional SCR series stack unit through a metal interconnection line is provided in the second N-type well area, and a P+ heavily doped active area connected to the positive electrode of the electrostatic protection device through a metal interconnection line is also provided in the second N-type well area; the positive electrode of the electrostatic protection device is connected to the I / O port one, the negative electrode of the electrostatic protection device is connected to the I / O port two, and the semiconductor substrate is also provided with a plurality of electrostatic protection rings, which are grounded P+ heavily doped active areas. In this embodiment, as shown in FIG2 (a), the bidirectional SCR series stack unit is a protection unit module with hysteresis characteristics, and its on-resistance increases linearly with the number of added modules. However, due to its stronger current discharge, it has hysteresis characteristics, and the amplitude of the hysteresis is adjustable, so that a wider Vc can be provided; a bidirectional SCR series stack unit with hysteresis characteristics is added in series to the existing bidirectional BJT series stack unit to form a new bidirectional electrostatic protection stack architecture. By adjusting the type, number and proportion (the number of M and N) of the bidirectional SCR series stack units added in series, the overall Vc of the electrostatic protection device can be freely and flexibly adjusted to meet the high-voltage ESD design window, and the ESD protection level is effectively improved without the risk of latch-up. As shown in FIG2 (b), the dotted line is a schematic diagram of the IV curve of the existing bidirectional BJT stacking solution, and the Vc is obviously higher; the solid line is a new bidirectional electrostatic protection stack architecture at the same voltage, and the Vc is significantly reduced. Figure 3 As shown, the stacked architecture is fully compatible with the mature CMOS (Complementary Metal Oxide Semiconductor) process and can be used for bidirectional electrostatic protection between I / O ports. In this case, multiple electrostatic protection rings of the semiconductor substrate need to be grounded.

[0032] As shown in Figures 4 (a) to 4 (c), the positive electrode of the electrostatic protection device is connected to the I / O port, the negative electrode of the electrostatic protection device is grounded, and the semiconductor substrate is also provided with multiple electrostatic protection rings, which include a grounded P+ heavily doped active area and an N+ heavily doped active area connected to the power supply; the bidirectional BJT series stack unit is transformed from a planar metal oxide semiconductor field effect tube or a planar bipolar junction transistor or a vertical bipolar junction transistor, and the bidirectional SCR series stack unit is a bidirectional thyristor rectifier. In this embodiment, it can be used for the protection of the I / O port and the GND port. At this time, adding a grounded P+ heavily doped active area and a N+ heavily doped active area connected to the power supply as a double protection ring can avoid the grounded P+ heavily doped active area from inducing abnormal latching problems when reverse conduction. Figure 4 (a) is a schematic diagram of the layout of the bidirectional SCR series stack unit, which consists of the layout of the bidirectional BJT series stack unit and the bidirectional SCR series stack unit. The electrostatic discharge path of the bidirectional BJT series stack unit is a bidirectional NPN path. The electrostatic discharge path of the bidirectional SCR series stack unit includes a bidirectional NPN path, a forward SCR path, and a reverse SCR path. By adjusting the split area ratio of the P+ heavily doped active area and the N+ heavily doped active area of ​​the first P-type ESD protection layer, and the split area ratio of the P+ heavily doped active area and the N+ heavily doped active area of ​​the second P-type ESD protection layer, the hysteresis depth of the bidirectional SCR path can be further controlled, thereby achieving a more precise adjustment of Vc. Wherein, 100 represents a semiconductor substrate, 200 and 301 represent a second N-type well region, 210 and 311 represent a first N-type well region, 111, 112, 120, 201, 202, 211, 216, 315, 315-1, 315-2, 315-3, 317, 317-1, 317-2, 317-3, 411, 412, 511, 512 represent a P+ heavily doped active area, 213, 214, 303, 304, 305, 313, 318, 318-1, 318-2, 318-3, 319, 319-1, 319-2, 319-3 represent N+ heavily doped active areas, 212 represents a first P-type ESD protection layer, 215 represents a second P-type ESD protection layer, and 101, 102, 103, 104, 105, 106, 107, 108, 109 represent metal interconnects.

[0033] The manufacturing process of an electrostatic protection device with a bidirectional SCR path of the present invention is applicable to various common integrated circuit manufacturing processes, such as nano-scale complementary metal oxide semiconductor (CMOS) process, three-dimensional fin field effect transistor (FinField-EffectTransistor, FinFET) or gate-all-around FET (GAA) process, or silicon-on-insulator (SOI) process, etc.

[0034] As can be seen from the above, the present invention provides an electrostatic protection device with a bidirectional SCR path, and a new bidirectional electrostatic protection stacking architecture is formed by adding a bidirectional SCR series stacking unit with hysteresis characteristics in series to a traditional bidirectional BJT series stacking unit. The bidirectional SCR path of the bidirectional SCR series stacking unit can reduce the overall clamping voltage Vc of the electrostatic protection device. While providing bidirectional electrostatic protection for the I / O port, adjusting the ratio of the number of bidirectional SCR series stacking units and the bidirectional BJT series stacking units can change the overall clamping voltage Vc of the electrostatic protection device. While maintaining the linear stacking of the working voltage of the electrostatic protection device, the overall clamping voltage of the electrostatic protection device can be flexibly adjusted. The design has a high degree of freedom and no latch-up risk, and the effective electrostatic protection level of the chip is significantly improved. The application range is wide, and it is particularly suitable for circuit protection with a wide working voltage range such as automotive electronic chips and high-voltage charging power chips. It solves the problem in the prior art that the traditional bidirectional BJT stacking method will cause a higher Vc and occupy a huge layout area.

[0035] The specific implementation modes described above are preferred implementation modes of the present invention, and are not intended to limit the specific implementation scope of the present invention. The scope of the present invention includes but is not limited to the specific implementation modes, and all equivalent changes made according to the present invention are within the protection scope of the present invention.

Claims

1. An electrostatic protection device with a bidirectional SCR path, characterized in that: The invention comprises a semiconductor substrate and N bidirectional BJT series stacking units and M bidirectional SCR series stacking units arranged on the semiconductor substrate, wherein N and M are both positive integers, wherein the bidirectional BJT series stacking unit is connected in series with the bidirectional SCR series stacking unit through a metal interconnection line, wherein the bidirectional BJT series stacking unit is connected to the positive electrode of the electrostatic protection device through the metal interconnection line, wherein the bidirectional SCR series stacking unit is connected to the negative electrode of the electrostatic protection device through the metal interconnection line, wherein a first N-type well region is provided in the bidirectional SCR series stacking unit, wherein a first P-type ESD protection layer and a second P-type ESD protection layer are provided in the first P-type ESD protection layer, wherein a P+ heavily doped active region and an N+ heavily doped active region connected to the bidirectional BJT series stacking unit through the metal interconnection line, wherein a second P-type ESD protection layer is provided in the second P-type ESD protection layer The N+ heavily doped active area and the P+ heavily doped active area are connected to the negative electrode of the protection device, and a bidirectional SCR path with hysteresis characteristics is formed between the P+ heavily doped active area and the N+ heavily doped active area of ​​the first P-type ESD protection layer and the P+ heavily doped active area and the N+ heavily doped active area of ​​the second P-type ESD protection layer. The bidirectional SCR path can reduce the overall clamping voltage Vc of the electrostatic protection device, and adjusting the number ratio of the bidirectional SCR series stacking units and the bidirectional BJT series stacking units can change the overall clamping voltage Vc of the electrostatic protection device. The distance between the P+ heavily doped active area and the N+ heavily doped active area of ​​the first P-type ESD protection layer and the distance between the P+ heavily doped active area and the N+ heavily doped active area of ​​the second P-type ESD protection layer are both L1, L1≥0μm, and adjusting the size of L1 can adjust the hysteresis depth of the bidirectional SCR path.

2. The electrostatic protection device with a bidirectional SCR path according to claim 1, characterized in that: The number N of the bidirectional BJT series stacked units is less than the number M of the bidirectional SCR series stacked units.

3. The electrostatic protection device with a bidirectional SCR path according to claim 2, characterized in that: The divided area ratio of the P+ heavily doped active area and the N+ heavily doped active area of ​​the first P-type ESD protection layer and the divided area ratio of the P+ heavily doped active area and the N+ heavily doped active area of ​​the second P-type ESD protection layer can be adjusted.

4. The electrostatic protection device with a bidirectional SCR path according to claim 3, characterized in that: A second N-type well region is provided in the bidirectional BJT series stack unit, and a P+ heavily doped active region is provided in the second N-type well region and is connected to the bidirectional SCR series stack unit through a metal interconnection line. The second N-type well region is also provided with a P+ heavily doped active region connected to the positive electrode of the electrostatic protection device through a metal interconnection line.

5. The electrostatic protection device with a bidirectional SCR path according to claim 4, characterized in that: The positive electrode of the electrostatic protection device is connected to I / O port one, the negative electrode of the electrostatic protection device is connected to I / O port two, and the semiconductor substrate is also provided with a plurality of electrostatic protection rings, which are grounded P+ heavily doped active regions.

6. The electrostatic protection device with a bidirectional SCR path according to claim 5, characterized in that: The positive pole of the electrostatic protection device is connected to the I / O port, the negative pole of the electrostatic protection device is grounded, and the semiconductor substrate is also provided with a plurality of electrostatic protection rings, which include a grounded P+ heavily doped active area and an N+ heavily doped active area connected to a power supply.

7. The electrostatic protection device with a bidirectional SCR path according to claim 6, characterized in that: The bidirectional BJT series stack unit is transformed from a planar metal oxide semiconductor field effect tube or a planar bipolar junction transistor or a vertical bipolar junction transistor, and the bidirectional SCR series stack unit is a bidirectional silicon controlled rectifier.

8. The electrostatic protection device with a bidirectional SCR path according to claim 7, characterized in that: The manufacturing process of the electrostatic protection device with a bidirectional SCR path includes a nano-scale complementary metal oxide semiconductor process, a three-dimensional fin field effect transistor, a full-surround gate transistor process or a silicon on insulating substrate process.

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