A high voltage protection device and a manufacturing method thereof

Abstract

The present application is applicable to the technical field of semiconductor devices, and provides a high-voltage protection device, including a substrate, a buried layer and an epitaxial layer, which are stacked in sequence; based on the epitaxial layer, a first well and a high-voltage well are arranged in sequence from any point on the edge of the epitaxial layer to the center point; and a first active area is arranged on the first well; the high-voltage well has three closed annular vacant areas, and a second well, a third well and a fourth well are arranged in the three annular vacant areas respectively; and a second active area, a third active area and a fourth active area are arranged on the second well, the third well and the fourth well; a fifth well is arranged on the high-voltage well, and a fifth active area is arranged in the fifth well, thereby solving the technical problem that the SCR device in the prior art cannot be applied to ultra-high voltage withstand occasions.

Description

Technical Field

[0001] The present application belongs to the technical field of semiconductor devices, and in particular, relates to a high-voltage protection device and a manufacturing method thereof. Background Art

[0002] As the size of semiconductor processes shrinks, the gap between device operating voltage and breakdown voltage becomes smaller and smaller, and the electrostatic discharge (ESD) problem of integrated circuits becomes more and more prominent. Usually, the operating voltage of the chip port is between 0V and the power supply voltage, so the ESD structure of the common device port only needs to ensure that the ESD device has no leakage current when the port voltage is between 0V and the power supply voltage.

[0003] When an ESD event occurs, the existing high-trigger positive voltage-resistant SCR device triggers the SCR structure, which requires the voltage between the port PAD and the ground to exceed the reverse breakdown voltage of the PN junction. This structure is only applicable when the normal working voltage of the PAD is higher than the ground voltage.

[0004] However, in actual applications, some chips may have a port voltage far higher than the power supply voltage or a negative voltage lower than the ground potential. In this case, the parasitic PN junction of the SCR device will be turned on, resulting in a large leakage current at the port, making the port signal incomplete and affecting the actual use of the entire chip. In addition, the conduction of the thyristor (Silicon Controlled Rectifier, SCR) device is triggered by reverse breakdown of the PN junction of the N-well and P-well, so it cannot be used in ultra-high withstand voltage applications, and some applications have special requirements such as low leakage current. Summary of the invention

[0005] The embodiments of the present application provide a high-voltage protection device and a manufacturing method, which can solve the technical problem in the prior art that SCR devices cannot be applied to ultra-high voltage applications.

[0006] In a first aspect, an embodiment of the present application provides a high voltage protection device, including:

[0007] substrate;

[0008] buried layer;

[0009] An epitaxial layer, wherein the substrate, the buried layer and the epitaxial layer are stacked in sequence;

[0010] Based on the epitaxial layer, a first well and a high-voltage well are sequentially arranged from any point on the edge of the epitaxial layer to the center point; and a first active area is arranged on the first well;

[0011] The high-voltage well has three closed annular vacant areas, and a second well, a third well, and a fourth well are respectively arranged in the three annular vacant areas; and a second active area, a third active area, and a fourth active area are arranged on the second well, the third well, and the fourth well;

[0012] A fifth well is provided on the high-voltage well, and a fifth active region is provided on the fifth well;

[0013] The doping type of the substrate, the epitaxial layer, the first well, the second well, the third well, the fourth well, the first active region and the third active region is a first type;

[0014] The doping types of the buried layer, the fifth well, the second active region, the fourth active region and the fifth active region are of the second type; the first type is different from the second type.

[0015] In a possible implementation manner of the first aspect, the first well, the second well, the third well, the fourth well, and the fifth well are all closed rings.

[0016] In a possible implementation of the first aspect, the doping concentration of the high-voltage well is respectively less than the doping concentration of the first well, the doping concentration of the second well, the doping concentration of the third well, the doping concentration of the fourth well, and the doping concentration of the fifth well.

[0017] In a possible implementation of the first aspect, the fifth active region is suspended; the first active region, the second active region, the third active region and the fourth active region of the second well, and the second active region, the third active region and the fourth active region of the fourth well constitute the first end of the high-voltage protection device; the second active region, the third active region and the fourth active region of the third well constitute the second end of the high-voltage protection device; any one of the first end of the high-voltage protection device and the second end of the high-voltage protection device is an anode, and the remaining end is a cathode.

[0018] In a possible implementation manner of the first aspect, the first type of doping is P doping; the second type of doping is N doping; or,

[0019] The first type of doping is N-doping; the second type of doping is P-doping.

[0020] In a possible implementation of the first aspect, the high-voltage well includes a first high-voltage sub-well, a second high-voltage sub-well, and a third high-voltage sub-well that are interconnected, and each sub-well is arranged around an annular vacant area. The fifth well includes a first sub-well, a second sub-well, and a third sub-well that are interconnected, and each sub-well is arranged one-to-one on each high-voltage sub-well; the fifth active area includes a first sub-active area, a second sub-active area, and a third sub-active area, and each sub-active area is arranged one-to-one on each sub-well.

[0021] In a possible implementation manner of the first aspect, the third well is an emitter, the second high-voltage sub-well and the second sub-well are bases, and the second well and the fourth well are collectors, so as to form a lateral PNP transistor 1;

[0022] The second high-voltage sub-well and the second sub-well are used as collectors, the second well and the fourth well are used as bases, and the fourth active region and the second sub-active region of the second well are used as emitters, so as to form a lateral NPN transistor 1;

[0023] The buried layer is a collector, the second well and the fourth well are bases, and the fourth active region and the second sub-active region of the second well are emitters, so as to form a vertical NPN transistor 2;

[0024] The lateral NPN transistor 1 , the longitudinal NPN transistor 2 and the lateral PNP transistor 1 form a forward thyristor structure.

[0025] In a possible implementation of the first aspect, the second well and the fourth well are emitters, the second high-voltage sub-well and the second sub-well are bases, and the third well is a collector, so as to form a lateral PNP transistor 2;

[0026] The second high-voltage sub-well is used as a collector, the third well is used as a base, and the second active region and the fourth active region of the third well are used as an emitter, so as to form a lateral NPN transistor 3;

[0027] The buried layer is a collector, the third well is a base, and the second active region and the fourth active region of the third well are emitters, so as to form a vertical NPN transistor 4;

[0028] The lateral NPN transistor 3 , the longitudinal NPN transistor 4 and the lateral PNP transistor 2 form an inverting thyristor structure.

[0029] In a second aspect, an embodiment of the present application provides a method for manufacturing a high-voltage protection device, comprising:

[0030] forming a buried layer on the substrate by diffusion or ion implantation;

[0031] forming an epitaxial layer on the buried layer by epitaxial growth;

[0032] Forming a first well on the epitaxial layer by first-type doping and forming a high-voltage well having three closed annular vacant areas by inversion doping;

[0033] Forming a second well, a third well and a fourth well in the three annular vacant regions respectively by first type doping;

[0034] forming a first active region on the first well by first type doping;

[0035] By first type doping and second type doping, a second active region, a third active region and a fourth active region are arranged on the second well, the third well and the fourth well;

[0036] forming a fifth well in the high-voltage well by second-type doping;

[0037] forming a fifth active region in the fifth well by second type doping;

[0038] Wherein, the doping type of the substrate, the epitaxial layer, the first well, the second well, the third well, the fourth well, the first active region and the third active region is the first type;

[0039] The doping types of the buried layer, the fifth well, the second active region, the fourth active region and the fifth active region are of the second type; the first type is different from the second type.

[0040] In a possible implementation manner of the second aspect, the first active region, the second active region, the third active region and the fourth active region of the second well, and the second active region, the third active region and the fourth active region of the fourth well are connected by metal wires to form a first end of the high-voltage protection device;

[0041] The second active region, the third active region and the fourth active region of the third well are connected by metal wires to form a second end of the high voltage protection device;

[0042] Wherein, any one of the first end of the high-voltage protection device and the second end of the high-voltage protection device is an anode, and the remaining end is a cathode.

[0043] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0044] By pre-setting a first well and a high-voltage well of a special shape, setting a second well, a third well and a fourth well in the annular vacant area reserved in the high-voltage well, setting a fifth well on the high-voltage well, and performing doping in the first to fifth wells to form multiple active areas, a special PN junction consisting of the high-voltage well and other wells can be formed in the high-voltage protection device, and a special connection of multiple PN junctions can be achieved through the above-mentioned setting process, and the effect of equal forward breakdown voltage and reverse breakdown voltage can be achieved through the above-mentioned structure, thereby greatly improving the limit values ​​of the reverse breakdown voltage and the forward breakdown voltage of the finally formed high-voltage protection device, and solving the technical problem in the prior art that the SCR device cannot be applied to ultra-high voltage withstand occasions. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0046] Figure 1 is a cross-sectional schematic diagram of a high-voltage protection device provided in one embodiment of the present application;

[0047] Figure 2 It is a cross-sectional and top view comparison structure diagram of a high-voltage protection device provided in one embodiment of the present application;

[0048] Figure 3 is a schematic diagram of an equivalent circuit of a high voltage protection device provided in one embodiment of the present application;

[0049] Figure 4 is a schematic diagram of an equivalent circuit of a high voltage protection device provided in one embodiment of the present application;

[0050] Figure 5 It is a flow chart of a method for manufacturing a high-voltage protection device provided in another embodiment of the present application. DETAILED DESCRIPTION

[0051] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present application. However, it should be clear to those skilled in the art that the present application may also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present application.

[0052] It should be understood that when used in the present specification and the appended claims, the term "comprising" indicates the presence of described features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0053] It should also be understood that the term “and / or” used in the specification and appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0054] As used in the specification and appended claims of this application, the term "if" can be interpreted as "when" or "uponce" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrase "if it is determined" or "if [described condition or event] is detected" can be interpreted as meaning "uponce it is determined" or "in response to determining" or "uponce [described condition or event] is detected" or "in response to detecting [described condition or event]", depending on the context.

[0055] In addition, in the description of the present application specification and the appended claims, the terms "first", "second", "third", etc. are only used to distinguish the descriptions and cannot be understood as indicating or implying relative importance.

[0056] References to "one embodiment" or "some embodiments" etc. described in the specification of this application mean that one or more embodiments of the present application include specific features, structures or characteristics described in conjunction with the embodiment. Therefore, the statements "in one embodiment", "in some embodiments", "in some other embodiments", "in some other embodiments", etc. that appear in different places in this specification do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized in other ways.

[0057] The present invention aims to solve the technical problem that the SCR device in the prior art cannot be applied to ultra-high withstand voltage occasions. The present invention provides a manufacturing method and device of a protection device, equipment and a computer-readable storage medium.

[0058] In one embodiment, Figure 1 as well as Figure 2A schematic structural diagram of a high-voltage protection device provided in the present application is shown, wherein the high-voltage protection device comprises a substrate 101, a buried layer 102 and an epitaxial layer, wherein the substrate 101, the buried layer 102 and the epitaxial layer are stacked in sequence; based on the epitaxial layer, a first well 201, 213 and a high-voltage well HVNW are sequentially arranged from any point on the edge of the epitaxial layer to the center point; and a first active area is arranged on the first well 201, 213; the high-voltage well HVNW has three closed annular vacant areas, and a second well 204, a third well 207 and a fourth well 210 are respectively arranged in the three annular vacant areas; and a second active area, a third active area and a fourth active area are arranged on the second well 204, the third well 207 and the fourth well 210; a fifth well is arranged on the high-voltage well HVNW, and a fifth active area is arranged on the fifth well.

[0059] Among them, the doping type of the substrate 101, the epitaxial layer, the first well 201, 213, the second well 204, the third well 207, the fourth well 210, the first active region and the third active region is the first type; the doping type of the buried layer 102, the fifth well NW, the second active region, the fourth active region and the fifth active region is the second type; the first type is different from the second type.

[0060] In the above embodiment, by pre-setting the first wells 201, 213 and the high-voltage well HVNW of a special shape, setting the second well 204, the third well 207 and the fourth well 210 in the annular vacant area reserved in the high-voltage well HVNW, setting the fifth well NW on the high-voltage well HVNW, and performing doping from the first wells 201, 213 to the fifth well NW to form multiple active areas, a special PN junction consisting of the high-voltage well HVNW and other wells can be formed in the high-voltage protection device, and the special connection of multiple PN junctions is achieved through the above setting process, and the effect of equal forward breakdown voltage and reverse breakdown voltage is achieved through the above structure, so that the reverse breakdown voltage and forward breakdown voltage of the finally formed high-voltage protection device can be greatly improved, and the technical problem that the SCR device in the prior art cannot be applied to ultra-high voltage applications is solved.

[0061] It should be noted that in the above solution, since the second well 204, the third well 207 and the fourth well 210 are separated by the high voltage well HVNW, they are actually isolated. The isolation ring has the characteristic of low leakage, so it can also effectively prevent problems such as parasitic field tubes.

[0062] Optionally, the first wells 201 and 213 , the second well 204 , the third well 207 , the fourth well 210 , and the fifth well NW are all closed rings.

[0063] Among them, the closed loop can better isolate each active area and the well, thereby reducing leakage to the greatest extent and more effectively preventing problems such as parasitic field tubes.

[0064] Optionally, the doping concentration of the high voltage well HVNW is respectively smaller than the doping concentrations of the first wells 201 , 213 , the second well 204 , the third well 207 , the fourth well 210 , and the fifth well NW.

[0065] Among them, the doping concentration of the high-voltage well HVNW is set to be lower than the doping concentration of the first wells 201 and 213, the doping concentration of the second well 204, the doping concentration of the third well 207, the doping concentration of the fourth well 210 and the doping concentration of the fifth well NW, so as to ensure the low doping of the high-voltage well HVNW at this time, and it can also be set to be lower than the doping concentration of all active areas, so as to further improve the forward and reverse breakdown voltages of the formed PN junction.

[0066] In a possible implementation, the fifth active region is suspended; the first active region, the second active region 403, the third active region 404 and the fourth active region 405 of the second well 204, and the second active region 411, the third active region 412 and the fourth active region 413 of the fourth well 210 constitute the first end of the high-voltage protection device; the second active region 407, the third active region 408 and the fourth active region 409 of the third well 207 constitute the second end of the high-voltage protection device; any one of the first end of the high-voltage protection device and the second end of the high-voltage protection device is an anode, and the remaining end is a cathode.

[0067] Through the above implementation method, the formation of the PN junction can be guaranteed, and the effect of improving the breakdown voltage value in the forward and reverse directions can be fully realized. When the BCD 0.5um process is adopted, the reverse breakdown voltage can be 70V in the laboratory measurement, so the forward trigger voltage can be 70V and the reverse trigger voltage can be 70V. It can play a role in resisting positive and negative high-voltage ESD protection, and has the characteristics of low leakage current. The ESD protection capability is 15KV under the Human-Body Model (HBM).

[0068] In a possible implementation manner, the first type of doping is P doping; and the second type of doping is N doping.

[0069] In a possible implementation manner, the first type of doping is N-doping; and the second type of doping is P-doping.

[0070] In the above two solutions, the types of P doping and N doping can be flexibly replaced to achieve equivalent effects.

[0071] In a possible implementation, the high-voltage well HVNW includes a first high-voltage sub-well 203, 206, a second high-voltage sub-well 206, 209 and a third high-voltage sub-well 209, 212 that are interconnected, and each sub-well is arranged around the annular vacant area. The fifth well NW includes a first sub-well 202, 205, a second sub-well 205, 208 and a third sub-well 208, 211 that are interconnected, and each sub-well is arranged one-to-one on each high-voltage sub-well; the fifth active area includes a first sub-active area 402, 406, a second sub-active area 406, 410 and a third sub-active area 410, 414, and each sub-active area is arranged one-to-one on each sub-well.

[0072] Through the above process, each sub-well, high-voltage sub-well and sub-active area that may be individually connected is isolated as a separate area, thereby achieving better low leakage current and isolation effects.

[0073] Based on the above embodiments, the working principle of the protection device is further described with an embodiment: Figure 3 As shown, the third well 207 is an emitter, the second high-voltage sub-wells 206, 209 and the second sub-wells 205, 208 are bases, and the second well 204 and the fourth well 210 are collectors, so as to form a lateral PNP transistor 1;

[0074] The second high-voltage sub-wells 206 and 209 and the second sub-wells 205 and 208 are used as collectors, the second well 204 and the fourth well 210 are used as bases, and the fourth active region of the second well 204 and the second sub-active regions 406 and 410 are used as emitters to form a lateral NPN transistor 1;

[0075] The buried layer 102 is a collector, the second well 204 and the fourth well 210 are bases, and the fourth active region of the second well 204 and the second sub-active regions 406 and 410 are emitters, so as to form a vertical NPN transistor 2;

[0076] The lateral NPN transistor 1 , the longitudinal NPN transistor 2 and the lateral PNP transistor 1 form a forward thyristor structure.

[0077] In this structure, since the SCR structure is the same from GND to PAD and from PAD to GND, this structure can withstand positive and negative voltages. When an ESD event occurs, when the PAD voltage is higher than the GND voltage and reaches the breakdown voltage of the high-voltage N-well (HVNW) 206, 209 and the P-well (PW) 204, 210, the PN junction is broken down, and the current flows from the high-voltage N-well (HVNW) 206, 209 to the P-well (PW) 204, 210, the lateral PNP transistor 1, the lateral NPN transistor 1 and the longitudinal NPN transistor 2 are turned on, and the forward SCR is triggered.

[0078] Optionally, refer to Figure 4 As shown, the second well 204 and the fourth well 210 are emitters, the second high-voltage sub-wells 206 and 209 and the second sub-wells 205 and 208 are bases, and the third well 207 is used as a collector to form a lateral PNP transistor 2;

[0079] The second high-voltage sub-wells 206 and 209 serve as collectors, the third well 207 serves as a base, and the second active region and the fourth active region of the third well 207 serve as emitters, so as to form a lateral NPN transistor 3;

[0080] The buried layer 102 is a collector, the third well 207 is a base, and the second active region and the fourth active region of the third well 207 are emitters, so as to form a vertical NPN transistor 4;

[0081] The lateral NPN transistor 3 , the longitudinal NPN transistor 4 and the lateral PNP transistor 2 form an inverting thyristor structure.

[0082] Among them, when the GND voltage is higher than the PAD voltage and reaches the breakdown voltage of the high-voltage N-well (HVNW) 206, 209 and the P-well (PW) 207, the PN junction is broken down, and the current flows from the high-voltage N-well (HVNW) 206, 209 to the P-well (PW) 207, the lateral PNP transistor 2, the lateral NPN transistor 3 and the longitudinal NPN transistor 4 are turned on, and the reverse SCR is triggered.

[0083] Since the high voltage N wells (HVNW) 206 and 209 are lightly doped wells, the PN junction breakdown voltage formed by the high voltage N wells (HVNW) 206 and 209 and the P wells (PW) 204, 207, and 210 is very high, and the high voltage resistance characteristic can be achieved.

[0084] Furthermore, the device can adopt the BCD 0.5um process, and its structure is triggered by the PN junction formed by the high-voltage N-well and the P-well. The reverse breakdown voltage of the PN junction is 70V, so it can achieve a forward trigger voltage of 70V and a reverse trigger voltage of 70V. It can play a role in withstanding positive and negative high-voltage ESD protection, and has the characteristics of low leakage current. The ESD protection capability is 15KV under the Human-Body Model (HBM).

[0085] Corresponding to the high voltage protection device described in the above embodiment, Figure 5 A flow chart of a method for manufacturing a high-voltage protection device provided in an embodiment of the present application is shown. For ease of explanation, only the part related to the embodiment of the present application is shown.

[0086] Reference Figure 5 , a method for manufacturing a high-voltage protection device, the method for manufacturing a high-voltage protection device is used to manufacture the high-voltage protection device as described above, comprising:

[0087] S1, forming a buried layer 102 on the substrate 101 by diffusion or ion implantation;

[0088] S2, forming an epitaxial layer on the buried layer 102 by epitaxial growth;

[0089] S3, forming first wells 201 and 213 on the epitaxial layer by first type doping and forming a high-voltage well HVNW having three closed annular vacant areas by inversion doping;

[0090] S4, forming a second well 204, a third well 207 and a fourth well 210 in the three annular vacant regions respectively by first type doping; and forming a first active region on the first wells 201 and 213 by first type doping;

[0091] S5, disposing a second active region, a third active region and a fourth active region on the second well 204, the third well 207 and the fourth well 210 by first type doping and second type doping; and forming a fifth well NW in the high voltage well HVNW by second type doping;

[0092] S6, forming a fifth active region in the fifth well NW by second type doping;

[0093] The doping type of the substrate 101, the epitaxial layer, the first wells 201 and 213, the second well 204, the third well 207, the fourth well 210, the first active region and the third active region is the first type;

[0094] The doping type of the buried layer 102 , the fifth well NW, the second active region, the fourth active region and the fifth active region is a second type; the first type is different from the second type.

[0095] By pre-setting the first well 201, 213 and a high-voltage well HVNW of a special shape, setting the second well 204, the third well 207 and the fourth well 210 in the annular vacant area reserved in the high-voltage well HVNW, setting the fifth well NW on the high-voltage well HVNW, and performing doping to form multiple active areas in the first well 201, 213 to the fifth well NW, a special PN junction consisting of the high-voltage well HVNW and other wells can be formed in the high-voltage protection device, and the special connection of multiple PN junctions can be achieved through the above-mentioned setting process, and the effect of equal forward breakdown voltage and reverse breakdown voltage can be achieved through the above-mentioned structure, so that the limit values ​​of the reverse breakdown voltage and the forward breakdown voltage of the finally formed high-voltage protection device can be greatly improved, and the technical problem that the SCR device in the prior art cannot be applied to ultra-high voltage withstand occasions can be solved.

[0096] In an optional implementation manner, the method for manufacturing the high-voltage protection device further includes:

[0097] The first active area, the second active area 403, the third active area 404 and the fourth active area 405 of the second well 204, the second active area 411, the third active area 412 and the fourth active area 413 of the fourth well 210 are connected by metal wires to form a first end of the high voltage protection device;

[0098] The second active region 407, the third active region 408 and the fourth active region 409 of the third well 207 are connected by metal wires to form the second end of the high voltage protection device;

[0099] Wherein, any one of the first end of the high-voltage protection device and the second end of the high-voltage protection device is an anode, and the remaining end is a cathode.

[0100] It should be understood that the size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0101] The embodiments described above are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A high voltage protection device, characterized in that: include: substrate; buried layer; An epitaxial layer, wherein the substrate, the buried layer and the epitaxial layer are stacked in sequence; Based on the epitaxial layer, a first well and a high-voltage well are sequentially arranged from any point on the edge of the epitaxial layer to the center point; and a first active area is arranged on the first well; The high-voltage well has three closed annular structures, the interior of the annular structures is an empty area, and the second well, the third well and the fourth well are respectively arranged in the three empty areas; and the second active area, the third active area and the fourth active area are arranged on the second well, the third well and the fourth well; A fifth well is provided on the high-voltage well, and a fifth active region is provided on the fifth well; The doping type of the substrate, the epitaxial layer, the first well, the second well, the third well, the fourth well, the first active region and the third active region is a first type; The doping types of the buried layer, the fifth well, the second active region, the fourth active region and the fifth active region are of the second type; the first type is different from the second type.

2. The high voltage protection device according to claim 1, characterized in that: The first well and the fifth well are both closed rings.

3. The high voltage protection device according to claim 1, characterized in that: The doping concentration of the high-voltage well is respectively smaller than the doping concentration of the first well, the doping concentration of the second well, the doping concentration of the third well, the doping concentration of the fourth well, and the doping concentration of the fifth well.

4. The high voltage protection device according to claim 1, characterized in that: The fifth active area is suspended; the first active area, the second active area, the third active area and the fourth active area of ​​the second well, and the second active area, the third active area and the fourth active area of ​​the fourth well constitute the first end of the high-voltage protection device; the second active area, the third active area and the fourth active area of ​​the third well constitute the second end of the high-voltage protection device; any one of the first end of the high-voltage protection device and the second end of the high-voltage protection device is an anode, and the remaining end is a cathode.

5. The high voltage protection device according to claim 1, characterized in that: The first type of doping is P doping; the second type of doping is N doping; or, The first type of doping is N-doping; the second type of doping is P-doping.

6. The high voltage protection device according to claim 1, characterized in that: The high-voltage well includes a first high-voltage sub-well, a second high-voltage sub-well and a third high-voltage sub-well which are interconnected, and each high-voltage sub-well is arranged around a vacant area respectively; the fifth well includes a first sub-well, a second sub-well and a third sub-well which are interconnected, and each sub-well is arranged one-to-one on each high-voltage sub-well; the fifth active area includes a first sub-active area, a second sub-active area and a third sub-active area, and each sub-active area is arranged one-to-one on each sub-well.

7. The high voltage protection device according to claim 6, characterized in that: The third well is an emitter, the second high-voltage sub-well and the second sub-well are bases, and the second well and the fourth well are collectors, so as to form a lateral PNP transistor 1; The second high-voltage sub-well and the second sub-well are used as collectors, the second well and the fourth well are used as bases, and the fourth active region and the second sub-active region of the second well are used as emitters, so as to form a lateral NPN transistor 1; The buried layer is a collector, the second well and the fourth well are bases, and the fourth active region and the second sub-active region of the second well are emitters, so as to form a vertical NPN transistor 2; The lateral NPN transistor 1 , the longitudinal NPN transistor 2 and the lateral PNP transistor 1 form a forward thyristor structure.

8. The high voltage protection device according to claim 6, characterized in that: The second well and the fourth well are emitters, the second high-voltage sub-well and the second sub-well are bases, and the third well is a collector, so as to form a lateral PNP transistor 2; The second high-voltage sub-well is used as a collector, the third well is used as a base, and the second active region and the fourth active region of the third well are used as an emitter, so as to form a lateral NPN transistor 3; The buried layer is a collector, the third well is a base, and the second active region and the fourth active region of the third well are emitters, so as to form a vertical NPN transistor 4; The lateral NPN transistor 3 , the longitudinal NPN transistor 4 and the lateral PNP transistor 2 form an inverting thyristor structure.

9. A method for manufacturing a high voltage protection device, characterized in that: The method for manufacturing the high-voltage protection device is used to manufacture the high-voltage protection device according to any one of claims 1 to 8, comprising: forming a buried layer on the substrate by diffusion or ion implantation; forming an epitaxial layer on the buried layer by epitaxial growth; Forming a first well on the epitaxial layer by first-type doping and forming a high-voltage well having three closed annular structures by inversion doping, wherein the interior of the annular structures is a vacant area; Forming a second well, a third well and a fourth well in the three vacant regions respectively by first type doping; and forming a first active region on the first well by first type doping; A second active region, a third active region and a fourth active region are disposed on the second well, the third well and the fourth well by first type doping and second type doping; and a fifth well is formed in the high-voltage well by second type doping; forming a fifth active region in the fifth well by second type doping; Wherein, the doping type of the substrate, the epitaxial layer, the first well, the second well, the third well, the fourth well, the first active region and the third active region is the first type; The doping types of the buried layer, the fifth well, the second active region, the fourth active region and the fifth active region are of the second type; the first type is different from the second type.

10. The method for manufacturing a high voltage protection device according to claim 9, characterized in that: The method for manufacturing the high-voltage protection device also includes: The first active area, the second active area, the third active area and the fourth active area of ​​the second well, the second active area, the third active area and the fourth active area of ​​the fourth well are connected by metal wires to form a first end of the high-voltage protection device; The second active region, the third active region and the fourth active region of the third well are connected by metal wires to form a second end of the high voltage protection device; Wherein, any one of the first end of the high-voltage protection device and the second end of the high-voltage protection device is an anode, and the remaining end is a cathode.

Images