Power tube isolation structure and power integrated circuit

Abstract

The present application provides a power tube isolation structure and a power integrated circuit, which collects electrons generated by the power tube through a first N-type isolation ring; absorbs the electrons generated by the power tube through a second P-type isolation ring and the power tube to form an electric field; and absorbs the electrons generated by the power tube through the second N-type isolation ring, thereby reducing the total amount of minority carriers injected into the substrate and the substrate current, reducing the interference current of the minority carriers transmitted laterally to the control part circuit, and achieving the function of protecting the normal operation of the control circuit.

Description

Technical Field

[0001] The present application belongs to the technical field of semiconductor devices, and in particular, relates to a power tube isolation structure and a power integrated circuit. Background Art

[0002] The power tube in the existing power integrated circuit is generally controlled by the control circuit. In order to avoid crosstalk between the power tube and the control circuit and ensure the normal operation of the control circuit, an isolation structure is usually set between the power tube and the control circuit.

[0003] However, it is generally difficult for existing isolation structures to completely isolate the substrate current generated by the minority carriers injected into the substrate by the power tube. When the substrate current passes through the substrate and reaches the logic control circuit, it is easy to form an interference current that interferes with the normal operation of the logic circuit, causing signal interference or latching in the control circuit, and may cause the entire power integrated circuit to fail. Summary of the invention

[0004] The purpose of the present application is to provide a power tube isolation structure and a power integrated circuit, aiming to solve the problem that the traditional power tube isolation structure has poor isolation effect and is prone to generate interference current.

[0005] In order to achieve the above objectives, in a first aspect, an embodiment of the present application provides a power tube isolation structure, including:

[0006] A first N-type isolation ring, wherein a substrate of the first N-type isolation ring is connected to a substrate of a first P-type isolation ring in the power tube and a substrate of the first N-type isolation ring is electrically connected to a doped end of the first P-type isolation ring or a doped end of a second P-type isolation ring, and is configured to collect electrons generated by the power tube;

[0007] The second P-type isolation ring, the substrate of the second P-type isolation ring is connected to the substrate of the first N-type isolation ring, and is configured to form an electric field with the power tube to absorb electrons generated by the power tube;

[0008] A second N-type isolation ring, wherein a substrate of the second N-type isolation ring is connected to a substrate of the second P-type isolation ring, is configured to absorb electrons generated by the power tube.

[0009] In a possible implementation of the first aspect, the doped end of the second P-type isolation ring is electrically connected to the doped end of the first N-type isolation ring, the doped end of the first P-type isolation ring is electrically connected to the ground pin, and the doped end of the second N-type isolation ring is electrically connected to the power pin.

[0010] In another possible implementation of the first aspect, the doped end of the second P-type isolation ring is electrically connected to the ground pin, the doped end of the first N-type isolation ring is electrically connected to the doped end of the first P-type isolation ring, and the doped end of the second N-type isolation ring is electrically connected to the power pin.

[0011] In another possible implementation manner of the first aspect, the power tube isolation structure further includes:

[0012] a third P-type isolation ring, the substrate of the third P-type isolation ring being connected to the substrate of the second N-type isolation ring and being configured to form an electric field with the second P-type isolation ring to absorb electrons generated by the power tube;

[0013] A third N-type isolation ring, the substrate of which is connected to the substrate of the third P-type isolation ring, is configured to absorb electrons generated by the power tube.

[0014] In another possible implementation of the first aspect, the doped end of the second P-type isolation ring is electrically connected to the ground pin, the doped end of the first N-type isolation ring is electrically connected to the doped end of the first P-type isolation ring, the doped end of the second N-type isolation ring is electrically connected to the doped end of the third P-type isolation ring, and the doped end of the third N-type isolation ring is electrically connected to the power pin.

[0015] In another possible implementation of the first aspect, the doped end of the second P-type isolation ring is electrically connected to the doped end of the second N-type isolation ring, the doped end of the first N-type isolation ring is electrically connected to the doped end of the first P-type isolation ring, the doped end of the third P-type isolation ring is electrically connected to the ground pin, and the doped end of the third N-type isolation ring is electrically connected to the power pin.

[0016] In another possible implementation of the first aspect, the doped end of the second P-type isolation ring is electrically connected to the doped end of the first N-type isolation ring, the doped end of the first P-type isolation ring is electrically connected to the ground pin, the doped end of the third P-type isolation ring is electrically connected to the doped end of the second N-type isolation ring, and the doped end of the third N-type isolation ring is electrically connected to the power pin.

[0017] In another possible implementation of the first aspect, the N-type isolation ring includes N-type doping, an N-well, a deep N-well, an N-type buried layer and a first substrate, the N-type buried layer is laid on the first substrate, the deep N-well is laid on the N-type buried layer, the N-well is laid on the deep N-well, and the N-type doping is laid on the N-well.

[0018] In another possible implementation of the first aspect, the P-type isolation ring includes P-type doping, a P-well, a P-type buried layer and a second substrate, the P-type buried layer is laid on the second substrate, the P-well is laid on the P-type buried layer, and the P-type doping is laid on the P-well.

[0019] In a second aspect, an embodiment of the present application provides a power integrated circuit, including the power tube isolation structure.

[0020] Compared with the prior art, the embodiments of the present invention have the following beneficial effects: the power tube isolation structure collects electrons generated by the power tube through the first N-type isolation ring; absorbs electrons generated by the power tube by forming an electric field with the power tube through the second P-type isolation ring; absorbs electrons generated by the power tube through the second N-type isolation ring, thereby reducing the total amount of minority carriers injected into the substrate and the substrate current, reducing the interference current of the minority carriers transmitted laterally to the control part circuit, and achieving the function of protecting the normal operation of the control circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] 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.

[0022] Figure 1 A schematic diagram of the overall structure of the power tube isolation structure provided in an embodiment of the present application;

[0023] Figure 2 This is the circuit diagram of a traditional power tube;

[0024] Figure 3 A schematic diagram of a first structural example of a power tube isolation structure provided in an embodiment of the present application;

[0025] Figure 4 A second structural schematic diagram of the power tube isolation structure provided in an embodiment of the present application;

[0026] Figure 5 A third structural schematic diagram of the power tube isolation structure provided in an embodiment of the present application;

[0027] Figure 6 A fourth structural schematic diagram of the power tube isolation structure provided in an embodiment of the present application;

[0028] Figure 7 A fifth structural schematic diagram of the power tube isolation structure provided in an embodiment of the present application.

[0029] Among them, the reference numerals in the figure are:

[0030] 1-first N-type isolation ring, 2-second P-type isolation ring, 3-second N-type isolation ring, 4-third P-type isolation ring, 5-third N-type isolation ring. DETAILED DESCRIPTION

[0031] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0032] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0033] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0034] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0035] At present, the power tubes in traditional power integrated circuits are controlled by low-voltage bipolar transistors and complementary metal oxide semiconductor (BiCMOS) circuits. Under certain specific circumstances, substrate current will be generated due to the injection of minority carriers from the power tube into the substrate, and part of the substrate current will reach the control circuit through the substrate to form interference current.

[0036] Figure 2 This is the circuit diagram of a traditional power tube, such as Figure 2As shown in the figure, the working principle of the power integrated circuit is that the upper tube (HS MOS) and the lower tube (LS MOS) are turned on alternately. Before the upper tube is turned off, the direction of the inductor current is from left to right (drain potential SW to output voltage VOUT). When the upper tube is turned off and the lower tube is not turned on, this period of time is called the dead time. Because the inductor current cannot change suddenly, the current will continue to flow through the parasitic diode of the substrate and the drain of the lower tube. GND is 0 potential, and the drain potential SW voltage must be negative to ensure that the parasitic diode is turned on for continuous flow. Therefore, during the dead time, the drain potential SW will have negative burrs, causing the isolation ring and the substrate (grounded, 0 potential) parasitic diode to be forward biased, and electrons will be injected into the substrate (relative to the P-type substrate, electrons are called minority carriers) to form substrate current. The generated substrate current may have a large amplitude (for example, 100mA). If there is no effective isolation between the power tube and the control circuit, a part of the substrate current will reach the control circuit through the substrate attenuation, forming a current that interferes with the normal operation of the control circuit, called interference current, which is easy to cause signal interference or latch-up in the low-power circuit, and may cause the entire power integrated circuit to fail.

[0037] In response to the above problems, the present application provides a power tube isolation structure, which forms an electric field between the internal isolation ring and the power tube to absorb the electrons generated by the power tube, thereby changing the floating substrate potential near the minority carrier injection point, reducing the total amount of minority carriers injected into the substrate, that is, reducing the substrate current, and reducing the substrate current reaching the control circuit, that is, reducing the interference current, and ultimately achieving the purpose of protecting the normal operation of the control circuit.

[0038] Figure 1 The overall structural diagram of the power tube isolation structure provided by an embodiment of the present application is as follows Figure 1 For the sake of convenience, only the parts related to this embodiment are shown, which are described in detail as follows: applied between the power tube and the control circuit, including:

[0039] A first N-type isolation ring 1, wherein the substrate of the first N-type isolation ring 1 is connected to the substrate of the first P-type isolation ring in the power tube and the doped end of the first N-type isolation ring is electrically connected to the doped end of the first P-type isolation ring or the doped end of the second P-type isolation ring, and is configured to collect electrons generated by the power tube;

[0040] A second P-type isolation ring 2, the substrate of which is connected to the substrate of the first N-type isolation ring 1, and is configured to form an electric field with the power tube to absorb electrons generated by the power tube;

[0041] The second N-type isolation ring 3 has a substrate connected to the substrate of the second P-type isolation ring 2 and is configured to absorb electrons generated by the power tube.

[0042] In this embodiment, the electrons generated by the power tube are collected by the first N-type isolation ring. When the doped end of the first N-type isolation ring is electrically connected to the doped end of the second P-type isolation ring, the doped end of the first P-type isolation ring is electrically connected to the ground pin, so that the second P-type isolation ring and the power tube form an electric field to absorb the electrons generated by the power tube; when the doped end of the first N-type isolation ring is electrically connected to the doped end of the first P-type isolation ring, the doped end of the second P-type isolation ring is electrically connected to the ground pin, so that the second P-type isolation ring and the power tube form an electric field to absorb the electrons generated by the power tube; the electrons are further absorbed by the second N-type isolation ring to prevent the electrons injected by the power tube from reaching the control circuit. Among them, the electrical connection can be a metal connection. At the same time, in the power tube, psub is a P-type substrate, p-epi is a P-type epitaxial layer, Ndrift is an N-type drain end drift injection, and Pbody is the channel part of the device.

[0043] Figure 3 A schematic diagram of a first structural example of a power tube isolation structure provided in an embodiment of the present application is shown in FIG. Figure 3 As shown, exemplarily, the doped end of the second P-type isolation ring 2 is electrically connected to the doped end of the first N-type isolation ring 1, the doped end of the first P-type isolation ring is electrically connected to the ground pin, and the doped end of the second N-type isolation ring 3 is electrically connected to the power pin.

[0044] In this embodiment, it is a multi-ring active analog junction isolation structure. When the drain potential SW is less than -0.7V, the present application is triggered, and electrons are collected through the first N-type isolation ring ND1. The first N-type isolation ring ND1 is transferred to the second P-type isolation ring P2 through a metal wire, thereby reducing the potential of the second P-type isolation ring P2. The potential of the second P-type isolation ring P2 is lower than the potential of the first P-type isolation ring P1 (PGND), forming a potential difference. The electric field generated by the second P-type isolation ring P2 and the first P-type isolation ring P1 prevents most of the electrons generated by the drain (D end, drain) from being injected into the control circuit, that is, reducing the interference current. However, when the drain potential SW is less than -1V, the structure reaches saturation and the blocking efficiency is reduced.

[0045] Figure 4 A second structural diagram of the power tube isolation structure provided in the embodiment of the present application is shown in FIG. Figure 4 As shown, the doped end of the second P-type isolation ring 2 is electrically connected to the ground pin, the doped end of the first N-type isolation ring 1 is electrically connected to the doped end of the first P-type isolation ring 2, and the doped end of the second N-type isolation ring 3 is electrically connected to the power pin.

[0046] In this embodiment, it is a negative feedback junction isolation structure. As the drain potential SW increases, the electrons collected by the first N-type isolation ring ND1 increase, and the potential of the first P-type isolation ring P1 decreases, thereby reducing the potential difference between the drain potential SW and the first P-type isolation ring P1, reducing the total amount of minority carriers injected into the substrate, and thus reducing ID The total current (the forward-biased PN junction current formed between the drain potential SW and the first P-type isolation ring P1) forms a negative feedback, which reduces the substrate current and further reduces the interference current.

[0047] When the drain potential SW is less than -0.7 V, the isolation effect of the multi-ring active analog junction isolation structure is roughly the same as that of the negative feedback junction isolation structure. When the drain potential SW is less than -1 V, the isolation effect of the negative feedback junction isolation is better than that of the multi-ring active analog junction isolation.

[0048] Exemplarily, the power tube isolation structure further includes:

[0049] A third P-type isolation ring 4, the substrate of which is connected to the substrate of the second N-type isolation ring 3, and is configured to form an electric field with the second P-type isolation ring 2 to absorb electrons generated by the power tube;

[0050] The third N-type isolation ring 5 , whose substrate is connected to the substrate of the third P-type isolation ring 4 , is configured to absorb electrons generated by the power tube.

[0051] In this embodiment, based on the above two structures, they can be used in combination if the chip area allows, to further block the substrate current of the power tube from reaching the control circuit. Specifically, an electric field is formed through the third P-type isolation ring and the second P-type isolation ring to generate a potential difference, thereby absorbing the electrons generated by the power tube, and further absorbing the electrons generated by the power tube through the third N-type isolation ring 5.

[0052] Figure 5 A third structural schematic diagram of the power tube isolation structure provided in the embodiment of the present application is shown in FIG. Figure 5 As shown, exemplarily, the doped end of the second P-type isolation ring 2 is electrically connected to the ground pin, the doped end of the first N-type isolation ring 1 is electrically connected to the doped end of the first P-type isolation ring, the doped end of the second N-type isolation ring 3 is electrically connected to the doped end of the third P-type isolation ring 4, and the doped end of the third N-type isolation ring 5 is electrically connected to the power pin.

[0053] In this embodiment, it is a negative feedback + multi-ring active analog junction isolation structure. As the drain terminal potential SW increases, the electrons collected by the first N-type isolation ring ND1 increase, and the potential of the first P-type isolation ring P1 is reduced through metal connection, thereby reducing the potential difference between the drain terminal (D terminal, drain) and the first P-type isolation ring P1, thereby reducing the substrate current.

[0054] At the same time, the electric field formed between the second P-type isolation ring P2 and the first P-type isolation ring P1 will cause the electrons to move toward the second P-type isolation ring P2. The voltage drop formed by the substrate resistance Rsub further reduces the potential of the first P-type isolation ring P1, forming a negative feedback, thereby reducing I DThe total current (the forward-biased PN junction current formed between the drain potential SW and the first P-type isolation ring P1) is reduced to reduce electron injection. At the same time, the doped end of the second N-type isolation ring ND2 and the doped end of the third P-type isolation ring P3 are suspended with metal short circuits, and the electrons injected from the drain are collected by the second N-type isolation ring ND2. The second N-type isolation ring ND2 is transferred to the third P-type isolation ring P3 through a metal wire, thereby reducing the potential of the third P-type isolation ring P3. Among them, the third P-type isolation ring P3 is lower than the potential of the second P-type isolation ring P2 (PGND), forming an electric potential difference, and the generated electric field further prevents electrons from being injected into the control circuit, thereby reducing interference current.

[0055] Figure 6 A fourth structural schematic diagram of the power tube isolation structure provided in the embodiment of the present application is shown in FIG. Figure 6 As shown, the doped end of the second P-type isolation ring 2 is electrically connected to the doped end of the second N-type isolation ring 3, the doped end of the first N-type isolation ring 1 is electrically connected to the doped end of the first P-type isolation ring, the doped end of the third P-type isolation ring 4 is electrically connected to the ground pin, and the doped end of the third N-type isolation ring 5 is electrically connected to the power pin.

[0056] In this embodiment, it is a double negative feedback junction isolation structure, the first N-type isolation ring ND1 absorbs electrons to reduce the potential of the first P-type isolation ring P1, and the second N-type isolation ring ND2 absorbs electrons to reduce the potential of the second N-type isolation ring ND2. At the same time, the electric field formed by the second P-type isolation ring P2 and the first P-type isolation ring P1, and the electric field formed by the third P-type isolation ring P3 and the second P-type isolation ring P2 will accelerate the electrons that are not absorbed to move to the third P-type isolation ring P3, thereby generating a larger voltage drop on the substrate, reducing the potential of the first P-type isolation ring P1, and reducing the potential difference between the drain end (D end, drain) and the first P-type isolation ring P1, thereby reducing I D The current (the forward-biased PN junction current formed between the drain potential SW and the first P-type isolation ring P1) is reduced, thereby reducing electron injection into the substrate and reducing the substrate current.

[0057] Figure 7 A fifth structural diagram of the power tube isolation structure provided in the embodiment of the present application is shown in FIG. Figure 7 As shown, exemplarily, the doped end of the second P-type isolation ring 2 is electrically connected to the doped end of the first N-type isolation ring 1, the doped end of the first P-type isolation ring is electrically connected to the ground pin, the doped end of the third P-type isolation ring 4 is electrically connected to the doped end of the second N-type isolation ring 3, and the doped end of the third N-type isolation ring 5 is electrically connected to the power pin.

[0058] In this embodiment, it is a dual multi-ring active analog junction isolation structure. The first N-type isolation ring ND1 absorbs electrons to reduce the potential of the second P-type isolation ring P2, and the second N-type isolation ring ND2 absorbs electrons to reduce the potential of the third P-type isolation ring P3. At this time, the potential of P3 < the potential of P2 < the potential of P1. The electric field formed by the third P-type isolation ring P3 and the second P-type isolation ring P2, as well as the electric field formed by the second P-type isolation ring P2 and the first P-type isolation ring P1, will both hinder most of the electrons generated at the drain end from injecting into the control circuit, reducing the interference current.

[0059] Exemplarily, the N-type isolation ring includes N-type doping, an N-well, a deep N-well, an N-type buried layer, and a first substrate. The N-type buried layer is laid on the first substrate, the deep N-well is laid on the N-type buried layer, the N-well is laid on the deep N-well, and the N-type doping is laid on the N-well.

[0060] In this embodiment, the N-type isolation ring structures of the first N-type isolation ring, the second N-type isolation ring, and the third N-type isolation ring are all the same. Specifically, the N-type buried layer can be laid on the first substrate, the deep N-well can be laid on the N-type buried layer, the N-well can be laid on the deep N-well, and the N-type doping can be laid on the N-well. The first substrate provides support and electrodes. The substrate leakage current is reduced through the N-type buried layer (NBL). Isolation from the outside is achieved through the deep N-well (DNW). The substrate is made through the N-well (NWell) and isolated from the outside. The positive electrode material is doped through the N-type doping (N+), such as phosphorus, arsenic, etc.

[0061] Exemplarily, the P-type isolation ring includes P-type doping, a P-well, a P-type buried layer, and a second substrate. The P-type buried layer is laid on the second substrate, the P-well is laid on the P-type buried layer, and the P-type doping is laid on the P-well.

[0062] In this embodiment, the P-type isolation ring structures of the first P-type isolation ring, the second P-type isolation ring, and the third P-type isolation ring are all the same. Specifically, the P-type buried layer can be laid on the second substrate, the P-well can be laid on the P-type buried layer, and the P-type doping can be laid on the P-well. The second substrate provides support and electrodes. The substrate leakage current is reduced through the P-type buried layer (PBL). The substrate is made through the P-well (PWell) and isolated from the outside. The negative electrode material is doped through the P-type doping (P+), such as boron, gallium, etc.

[0063] This application discloses a power integrated circuit, including a power transistor isolation structure.

[0064] In this embodiment, the power tube isolation structure is arranged between the power tube and the control circuit of the power integrated circuit, and the electrons generated by the power tube are collected by the first N-type isolation ring; the electrons generated by the power tube are absorbed by the second P-type isolation ring and the power tube to form an electric field; the electrons generated by the power tube are absorbed by the second N-type isolation ring, thereby reducing the total amount of minority carriers injected into the substrate and the substrate current, reducing the interference current of the minority carriers transmitted laterally to the control part circuit, and achieving the function of protecting the normal operation of the control circuit.

[0065] 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.

[0066] The technicians in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In practical applications, the above-mentioned function allocation can be completed by different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated in a processing unit, or each unit can exist physically separately, or two or more units can be integrated in one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of this application. The specific working process of the units and modules in the above-mentioned system can refer to the corresponding process in the aforementioned embodiment, which will not be repeated here.

[0067] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0068] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0069] In the embodiments provided in the present application, it should be understood that the disclosed power tube isolation structure can be implemented in other ways. For example, the power tube isolation structure embodiments described above are only schematic. For example, the division of the modules or units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0070] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0071] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0072] 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 power tube isolation structure, characterized in that: include: A first N-type isolation ring, wherein a substrate of the first N-type isolation ring is connected to a substrate of a first P-type isolation ring in the power tube and a doped end of the first N-type isolation ring is electrically connected to a doped end of the first P-type isolation ring or a doped end of a second P-type isolation ring, and is configured to collect electrons generated by the power tube; The second P-type isolation ring, the substrate of the second P-type isolation ring is connected to the substrate of the first N-type isolation ring, and is configured to form an electric field with the power tube to absorb electrons generated by the power tube; a second N-type isolation ring, the substrate of the second N-type isolation ring being connected to the substrate of the second P-type isolation ring and being configured to absorb electrons generated by the power tube; The N-type isolation ring comprises an N-type doping, an N-well, a deep N-well, an N-type buried layer and a first substrate, wherein the N-type buried layer is laid on the first substrate, the deep N-well is laid on the N-type buried layer, the N-well is laid on the deep N-well, and the N-type doping is laid on the N-well; The P-type isolation ring includes a P-type doping, a P-well, a P-type buried layer and a second substrate. The P-type buried layer is laid on the second substrate, the P-well is laid on the P-type buried layer, and the P-type doping is laid on the P-well.

2. The power tube isolation structure according to claim 1, characterized in that: The doped end of the second P-type isolation ring is electrically connected to the doped end of the first N-type isolation ring, the doped end of the first P-type isolation ring is electrically connected to the ground pin, and the doped end of the second N-type isolation ring is electrically connected to the power pin.

3. The power tube isolation structure according to claim 1, characterized in that: The doped end of the second P-type isolation ring is electrically connected to the ground pin, the doped end of the first N-type isolation ring is electrically connected to the doped end of the first P-type isolation ring, and the doped end of the second N-type isolation ring is electrically connected to the power pin.

4. The power tube isolation structure according to claim 1, characterized in that: The power tube isolation structure also includes: a third P-type isolation ring, the substrate of the third P-type isolation ring being connected to the substrate of the second N-type isolation ring and being configured to form an electric field with the second P-type isolation ring to absorb electrons generated by the power tube; A third N-type isolation ring, the substrate of which is connected to the substrate of the third P-type isolation ring, is configured to absorb electrons generated by the power tube.

5. The power tube isolation structure according to claim 4, characterized in that: The doped end of the second P-type isolation ring is electrically connected to the ground pin, the doped end of the first N-type isolation ring is electrically connected to the doped end of the first P-type isolation ring, the doped end of the second N-type isolation ring is electrically connected to the doped end of the third P-type isolation ring, and the doped end of the third N-type isolation ring is electrically connected to the power pin.

6. The power tube isolation structure according to claim 4, characterized in that: The doped end of the second P-type isolation ring is electrically connected to the doped end of the second N-type isolation ring, the doped end of the first N-type isolation ring is electrically connected to the doped end of the first P-type isolation ring, the doped end of the third P-type isolation ring is electrically connected to the ground pin, and the doped end of the third N-type isolation ring is electrically connected to the power pin.

7. The power tube isolation structure according to claim 4, characterized in that: The doped end of the second P-type isolation ring is electrically connected to the doped end of the first N-type isolation ring, the doped end of the first P-type isolation ring is electrically connected to the ground pin, the doped end of the third P-type isolation ring is electrically connected to the doped end of the second N-type isolation ring, and the doped end of the third N-type isolation ring is electrically connected to the power pin.

8. A power integrated circuit, characterized in that: The invention comprises the power tube isolation structure as described in any one of claims 1 to 7.

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