RC-IGBT structure and semiconductor device

Abstract

The invention discloses an RC-IGBT structure and a semiconductor device. The RC-IGBT structure comprises a substrate, a drift region of a first conduction type, a collector region of a second conduction type, a first trench gate and a base region of the second conduction type, a first emitter region of the first conductivity type; a second emitter region of a second conductivity type; the second trench gate extends into the drift region from the second main surface to the first main surface; the anode regions of the second conduction type are arranged on one side, facing the second main surface, of the drift region and are positioned on two sides of the trench gate in the horizontal direction; a channel cut-off region of a first conductive type, wherein the channel cut-off region is arranged at one side, far away from the first trench gate, of the anode region; wherein the anode region is conductively connected with the collector region through an external connecting line. According to the RC-IGBT structure and the semiconductor device, the voltage rebound phenomenon can be effectively eliminated.

Description

Technical Field

[0001] The present application relates to the field of semiconductor technology, and in particular to an RC-IGBT structure and a semiconductor device. Background Art

[0002] Power semiconductor devices play a key role in the field of power electronic conversion. As modern power systems continue to increase their requirements for power density, efficiency, and reliability, traditional IGBT (Insulated Gate Bipolar Transistor) devices face many challenges. RC-IGBT (Reverse Conducting-Insulated Gate Bipolar Transistor) devices have emerged as a new type of power semiconductor device. It integrates IGBT and freewheeling diode on the same chip, which can significantly reduce chip area, reduce costs, and increase power density compared to traditional IGBTs. In addition, during the shutdown process, the reverse recovery characteristics of the internal diode can be effectively used to suppress voltage spikes and reduce electromagnetic interference (EMI).

[0003] Existing RC-IGBT devices still have some technical problems, such as an inherent voltage rebound phenomenon.

[0004] Therefore, improvements are needed to at least partially solve the above problems. Summary of the invention

[0005] The present invention aims to at least partially solve the above problems. To this end, one object of the present invention is to provide an RC-IGBT structure that can eliminate the voltage rebound phenomenon. Another object of the present invention is to provide a semiconductor device having the RC-IGBT structure.

[0006] The RC-IGBT structure comprises:

[0007] A substrate, the substrate having a first main surface and a second main surface opposite to the first main surface, the first main surface and the second main surface being spaced apart in a vertical direction;

[0008] a drift region of a first conductivity type, the drift region being disposed between the first main surface and the second main surface;

[0009] A collector region of a second conductivity type, the collector region being disposed on a side of the drift region facing the first main surface, and a side of the collector region away from the drift region constituting at least a portion of the first main surface;

[0010] a first trench gate extending from the second main surface to the first main surface into the drift region;

[0011] A base region of a second conductivity type, the base region being disposed on a side of the drift region facing the second main surface and located on both sides of the first trench gate in a horizontal direction;

[0012] A first emitter region of a first conductivity type, the first emitter region being disposed on a side of the base region facing the second main surface, and a side of the first emitter region away from the first main surface constituting a portion of the second main surface;

[0013] a second emitter region of a second conductivity type, the second emitter region being disposed on a side of the base region facing the second main surface and on a side of the first emitter region away from the first trench gate, and the side of the second emitter region away from the first main surface constituting a part of the second main surface;

[0014] a second trench gate, the second trench gate extending from the second main surface to the first main surface into the drift region;

[0015] an anode region of a second conductivity type, the anode region being disposed on a side of the drift region facing the second main surface and being located on both sides of the second trench gate in a horizontal direction, and a side of the anode region away from the first main surface constituting a part of the second main surface;

[0016] A channel stop region of the first conductivity type, the channel stop region being arranged on a side of the anode region away from the first trench gate, and a side of the channel stop region away from the first main surface constituting a part of the second main surface;

[0017] Wherein, the anode region and the collector region are conductively connected via an external connecting line.

[0018] The above technical solution has the following advantages and beneficial effects: when the RC-IGBT structure is in the forward conduction state, a positive voltage is applied to the first trench gate and a negative voltage is applied to the second trench gate. At this time, an electron channel is generated under the first trench gate and a hole channel is generated under the second trench gate. Electrons and holes participate in the conduction process together. The RC-IGBT structure will not have a unipolar transport mode, eliminating the voltage rebound phenomenon.

[0019] In some embodiments, the first trench gate and the second trench gate are connected through an inverter.

[0020] The above technical solution has the following advantages and beneficial effects: the first trench gate and the second trench gate can be controlled together, and a negative voltage can be automatically applied to the second trench gate through an inverter while a positive voltage is applied to the first trench gate.

[0021] In some embodiments, the RC-IGBT structure further includes a first buffer zone of a first conductivity type, the first buffer zone is located between the anode region and the drift region, and is located on a side of the second trench gate facing the first trench gate;

[0022] The doping concentration of the first buffer region is greater than the doping concentration of the drift region.

[0023] The above technical solution has the following advantages and beneficial effects: the setting of the first buffer zone can change the electric field distribution of the RC-IGBT structure, so that the RC-IGBT structure can be cut off more quickly.

[0024] In some embodiments, the RC-IGBT structure further includes a carrier storage region of the first conductivity type, the carrier storage region being located between the base region and the drift region;

[0025] The doping concentration of the carrier storage region is greater than the doping concentration of the drift region.

[0026] The above technical solution has the following advantages and beneficial effects: the setting of the carrier storage area can effectively improve the switching speed of the RC-IGBT structure and stabilize the working state of the RC-IGBT structure.

[0027] In some embodiments, the RC-IGBT structure further includes a terminal structure, wherein the terminal structure is at least partially located between the anode region and the base region.

[0028] The above technical solution has the following advantages and beneficial effects: the setting of the terminal structure can effectively improve the withstand voltage of the RC-IGBT structure.

[0029] In some embodiments, the terminal structure includes at least one of a field plate, a field limiting ring, a JTE, and a VLD.

[0030] In some embodiments, the RC-IGBT structure further includes a second buffer zone of the first conductivity type, the second buffer zone being located between the drift region and the collector region;

[0031] The doping concentration of the second buffer region is greater than the doping concentration of the drift region.

[0032] The above technical solution has the following advantages and beneficial effects: the provision of the second buffer zone can effectively improve the withstand voltage of the RC-IGBT structure.

[0033] In some embodiments, the first trench gate includes a first gate trench extending from the second main surface to the first main surface to the drift region, a first gate dielectric layer located on an inner surface of the first gate trench, and a first polysilicon gate located on a side of the first gate dielectric layer away from the inner surface of the first gate trench;

[0034] The second trench gate includes a second gate trench extending from the second main surface to the first main surface to the drift region, a second gate dielectric layer located on the inner surface of the second gate trench, and a second polysilicon gate located on a side of the second gate dielectric layer away from the inner surface of the second gate trench.

[0035] In some embodiments, the first conductivity type is N-type;

[0036] The second conductivity type is P type.

[0037] The semiconductor device includes the RC-IGBT structure described above.

[0038] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The following drawings of the present application are hereby used as part of the present application for understanding the present application. The drawings show the embodiments of the present application and their descriptions, and are used to explain the device and principle of the present application. In the drawings,

[0040] Figure 1 FIG. 4 is a schematic diagram of an RC-IGBT structure according to an embodiment of the present application.

[0041] Description of reference numerals:

[0042] 100-substrate, 101-first main surface, 102-second main surface, 110-drift region, 111-collector region, 112-first trench gate, 113-base region, 114-first emitter region, 115-second emitter region, 116-second trench gate, 117-anode region, 118-channel stop region, 119-first buffer region, 120-carrier storage region, 121-terminal structure, 122-second buffer region;

[0043] 200-External connection line. DETAILED DESCRIPTION

[0044] In the following description, a large number of specific details are provided to provide a more thorough understanding of the present application. However, it is apparent to those skilled in the art that the present application can be implemented without one or more of these details. In other examples, in order to avoid confusion with the present application, some technical features well known in the art are not described.

[0045] It should be understood that the present application can be implemented in different forms and should not be construed as being limited to the embodiments presented herein. On the contrary, providing these embodiments will make the disclosure thorough and complete and fully convey the scope of the present application to those skilled in the art. In the accompanying drawings, the sizes and relative sizes of layers and regions may be exaggerated for clarity. The same reference numerals throughout represent the same elements.

[0046] It should be understood that although the terms first, second, third, etc. can be used to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or part from another element, component, region, layer or part. Therefore, without departing from the teachings of the present application, the first element, component, region, layer or part discussed below can be represented as a second element, component, region, layer or part.

[0047] Spatially relative terms such as "under", "beneath", "below", "under", "above", "above", etc., may be used herein for convenience of description to describe the relationship of one element or feature to other elements or features shown in the figures. It should be understood that the spatially relative terms are intended to encompass different orientations of the device in use and operation in addition to the orientation shown in the figures.

[0048] The purpose of the terms used herein is only to describe specific embodiments and is not intended to be limiting of the present application. When used herein, the singular forms "one", "an" and "said / the" are also intended to include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "consisting of" and / or "comprising", when used in this specification, determine the presence of the features, integers, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts and / or groups. When used herein, the term "and / or" includes any and all combinations of the relevant listed items.

[0049] Embodiments of the invention are described herein with reference to cross-sectional views as schematic diagrams of ideal embodiments (and intermediate structures) of the present application. Thus, variations in the shapes shown due to, for example, manufacturing techniques and / or tolerances can be expected. Therefore, embodiments of the present application should not be limited to the specific shapes shown herein, but include shape deviations due to, for example, manufacturing. Therefore, what is shown in the figures is schematic in nature, and their shapes are not intended to display the actual shape of the device and are not intended to limit the scope of the present application.

[0050] See attached Figure 1The RC-IGBT structure according to an embodiment of the present application is exemplarily described. In the following description, N and P represent the conductivity type of the semiconductor. In this embodiment, the first conductivity type is set as N type and the second conductivity type is set as P type for description.

[0051] The RC-IGBT structure includes: a substrate 100, a drift region 110 of a first conductivity type, a collector region 111 of a second conductivity type, a first trench gate 112, a base region 113 of a second conductivity type, a first emitter region 114 of a first conductivity type, a second emitter region 115 of a second conductivity type, a second trench gate 116, an anode region 117 of a second conductivity type, and a channel stop region 118 of a first conductivity type.

[0052] The base body 100 has a first main surface 101 and a second main surface 102 opposite to the first main surface 101 . The first main surface 101 and the second main surface 102 are spaced apart in the vertical direction.

[0053] The drift region 110 of the first conductivity type is disposed between the first main surface 101 and the second main surface 102. The drift region 110110 generally has a lower doping concentration, so it has a higher resistance and can withstand a higher voltage.

[0054] The collector region 111 of the second conductivity type is disposed on the side of the drift region 110 facing the first main surface 101, and the side of the collector region 111 away from the drift region 110 constitutes at least a portion of the first main surface 101. Exemplarily, a collector metal connected to the collector region 111 may be disposed on the first main surface 101.

[0055] The first trench gate 112 extends from the second main surface 102 to the first main surface 101 into the drift region 110. In the present embodiment, the first trench gate 112 includes a first gate trench extending from the second main surface 102 to the first main surface 101 into the drift region 110, a first gate dielectric layer located on the inner surface of the first gate trench, and a first polysilicon gate located on a side of the first gate dielectric layer away from the inner surface of the first gate trench. The first polysilicon gate is an active gate, that is, the first polysilicon gate is connected to an external drive signal source, and its potential is directly controlled by the external drive signal.

[0056] The base region 113 of the second conductivity type is arranged on the side of the drift region 110 facing the second main surface 102 and is located on both sides of the first trench gate 112 in the horizontal direction. The base region 113 can also be called a body region. Exemplarily, the side of the base region 113 away from the first main surface 101 can constitute part of the second main surface 102.

[0057] The first emitter region 114 of the first conductivity type is disposed on the side of the base region 113 facing the second main surface 102 , and the side of the first emitter region 114 away from the first main surface 101 constitutes part of the second main surface 102 . The doping concentration of the first emitter region 114 is higher than that of the drift region 110 .

[0058] The second emitter region 115 of the second conductivity type is arranged on the side of the base region 113 facing the second main surface 102, and is located on the side of the first emitter region 114 away from the first trench gate 112, and the side of the second emitter region 115 away from the first main surface 101 constitutes part of the second main surface 102. That is, in the horizontal direction, the first emitter region 114 is located between the first trench gate 112 and the second emitter region 115, and the first emitter region 114 is in contact with the first trench gate 112 and the second emitter region 115 on both sides in the horizontal direction. The doping concentration of the second emitter region 115 is higher than the doping concentration of the base region 113.

[0059] The second trench gate 116 extends from the second main surface 102 to the first main surface 101 into the drift region 110. In this embodiment, the second trench gate 116 includes a second gate trench extending from the second main surface 102 to the first main surface 101 into the drift region 110, a second gate dielectric layer located on the inner surface of the second gate trench, and a second polysilicon gate located on the side of the second gate dielectric layer away from the inner surface of the second gate trench. The second polysilicon gate is an active gate, that is, the second polysilicon gate is connected to an external drive signal source, and its potential is directly controlled by the external drive signal.

[0060] The anode region 117 of the second conductivity type is disposed on the side of the drift region 110 facing the second main surface 102 and is located on both sides of the second trench gate 116 in the horizontal direction, and the side of the anode region 117 away from the first main surface 101 constitutes part of the second main surface 102. In the horizontal direction, the side of the anode region 117 facing the second trench gate 116 is in contact with the second trench gate 116.

[0061] A channel stop region 118 of the first conductivity type is disposed on a side of the anode region 117 away from the first trench gate 112, and a side of the channel stop region 118 away from the first main surface 101 constitutes a portion of the second main surface 102. In the horizontal direction, a side of the channel stop region 118 facing the anode region 117 contacts the anode region 117. The doping concentration of the channel stop region 118 is higher than the doping concentration of the drift region 110.

[0062] The anode region 117 is conductively connected to the collector region 111 through an external connection line 200. It should be noted that the external connection line 200 mentioned here is a connection line outside the substrate 100, which may include conductive connection parts such as metal layers, metal columns, and wires. The second trench gate 116, the anode region 117 and the channel stop region 118 together constitute a front anode structure.

[0063] When the RC-IGBT structure according to the present embodiment is in a blocking state, a positive voltage is applied to the collector region 111, and no voltage is applied to the first trench gate 112 (i.e., the first polysilicon gate) and the second trench gate 116 (i.e., the second polysilicon gate). The voltages at the first trench gate 112 and the second trench gate 116 are both 0, and no conductive channel is generated.

[0064] According to the RC-IGBT structure of the present embodiment, when the RC-IGBT structure is in the forward conduction state, the collector region 111 and the first trench gate 112 (i.e., the first polysilicon gate) are positively voltageed, and the second trench gate 116 (i.e., the second polysilicon gate) is negatively voltageed. At this time, an electron channel is generated under the first trench gate 112, and a hole channel is generated under the second trench gate 116. Electrons and holes participate in the conduction process together, and the RC-IGBT structure does not have a unipolar transport mode, thereby effectively eliminating the voltage rebound phenomenon. At the same time, the collector region 111 and the anode region 117 both inject holes into the drift region 110, and the hole channel under the second trench gate 116 can also increase the hole injection efficiency of the anode region 117. At this time, the conductivity modulation effect in the drift region 110 is greatly enhanced compared to the traditional IGBT structure, which can effectively increase the current density of the RC-IGBT structure, so that the RC-IGBT structure has a smaller conduction voltage drop.

[0065] According to the RC-IGBT structure of this embodiment, when it is in the off state and the reverse conduction state, the first trench gate 112 (i.e., the first polysilicon gate) is negatively pressurized, and the second trench gate 116 (i.e., the second polysilicon gate) is positively pressurized. At this time, a hole channel and an electron channel are respectively induced under the first trench gate 112 and the second trench gate 116. In the off state, an electron and hole extraction channel can be provided to accelerate the extraction of electrons and holes and reduce the turn-off loss. In the reverse conduction state, the electron channel formed under the second trench gate 116 provides a path for the freewheeling diode.

[0066] In some embodiments, the first trench gate 112 (i.e., the first polysilicon gate) and the second trench gate 116 (i.e., the second polysilicon gate) are connected via an inverter. The inverter is used to invert the phase of the input signal by 180°. Assuming that the first trench gate 112 receives a positive voltage signal, after passing through the inverter, a negative voltage signal is transmitted to the second trench gate 116, and vice versa. This makes the control signals of the two trench gates always in opposite logical states. By setting the inverter, the first trench gate 112 and the second trench gate 116 can be controlled together, and a negative voltage can be automatically applied to the second trench gate 116 through the inverter while a positive voltage is applied to the first trench gate 112.

[0067] In this embodiment, the RC-IGBT structure further includes a first buffer zone 119 of the first conductivity type, the first buffer zone 119 is located between the anode region 117 and the drift region 110, and is located on the side of the second trench gate 116 facing the first trench gate 112. The doping concentration of the first buffer zone 119 is greater than the doping concentration of the drift region 110. The side of the first buffer zone 119 away from the first main surface 101 can constitute part of the second main surface 102, and in the horizontal direction, the side of the first buffer zone 119 away from the first trench gate 112 is in contact with the second trench gate 116. The provision of the first buffer zone 119 can change the electric field distribution of the RC-IGBT structure, so that the RC-IGBT structure can be turned off faster. In some embodiments, the first buffer zone 119 may not be provided between the anode region 117 and the drift region 110, and the anode region 117 is directly in contact with the drift region 110.

[0068] In this embodiment, the RC-IGBT structure further includes a carrier storage region 120 of the first conductivity type, and the carrier storage region 120 is located between the base region 113 and the drift region 110. The doping concentration of the carrier storage region 120 is greater than the doping concentration of the drift region 110. The side of the carrier storage region 120 away from the first main surface 101 can constitute part of the second main surface 102, and in the horizontal direction, the side of the carrier storage region 120 facing the first trench gate 112 is in contact with the first trench gate 112. The provision of the carrier storage region 120 can effectively improve the switching speed of the RC-IGBT structure, stabilize the working state of the RC-IGBT structure, so that the RC-IGBT structure will not generate excessive voltage spikes or current surges due to the rapid change of carriers, reduce switching losses, and allow the RC-IGBT structure to switch between the on state and the off state more quickly and stably. The carrier storage region 120 can also increase the withstand voltage capability of the RC-IGBT structure. It can help the drift region 110 withstand a higher reverse voltage and prevent the RC-IGBT structure from being broken down. In some embodiments, the carrier storage region 120 may not be disposed between the base region 113 and the drift region 110 , and the base region 113 is in direct contact with the drift region 110 .

[0069] In some embodiments, the RC-IGBT structure further includes a terminal structure 121, and the terminal structure 121 is at least partially located between the anode region 117 and the base region 113, and further, can be located between the first buffer region 119 and the carrier storage region 120. It should be noted that the term "located between the anode region 117 and the base region 113" (located between the first buffer region 119 and the carrier storage region 120) here refers to a position located between the two in the horizontal direction, and the terminal structure 121 can be located in the substrate 100, or outside the substrate 100, or partially in the substrate 100 and partially outside the substrate 100, and this application does not make specific restrictions on this. The provision of the terminal structure 121 can effectively improve the withstand voltage of the RC-IGBT structure.

[0070] Exemplarily, the terminal structure 121 may include at least one of a field plate, a field limiting ring, a JTE (Junction Termination Extension) and a VLD (Variation of Lateral Doping). The field plate, the field limiting ring, the JTE and the VLD are structures known to those skilled in the art and will not be described in detail here.

[0071] In this embodiment, the RC-IGBT structure further includes a second buffer zone 122 of the first conductivity type, the second buffer zone 122 is located between the drift region 110 and the collector region 111, and the doping concentration of the second buffer zone 122 is greater than the doping concentration of the drift region 110. The second buffer zone 122 contacts the drift region 110 and the collector region 111 on both sides in the vertical direction. The second buffer zone 122 may also be referred to as a field termination zone. The main function of the second buffer zone 122 is to terminate the electric field when the RC-IGBT structure is turned off, to prevent the electric field from penetrating into the collector region 111, thereby improving the withstand voltage capability. When a high voltage is applied, the second buffer zone 122 can withstand a portion of the electric field, so that the electric field gradually weakens before reaching the collector region 111, thereby avoiding the breakdown of the collector region 111. The second buffer zone 122 can also reduce the duration and amplitude of the tail current by adjusting the carrier distribution and extraction speed. The reduction of the tail current helps to reduce the turn-off loss. In some embodiments, the second buffer zone 122 may not be provided between the drift region 110 and the collector region 111.

[0072] The present application also provides a semiconductor device, which includes the RC-IGBT structure as described above.

[0073] Although example embodiments have been described herein with reference to the accompanying drawings, it should be understood that the above example embodiments are merely exemplary and are not intended to limit the scope of the present application to this. Those of ordinary skill in the art may make various changes and modifications therein without departing from the scope and spirit of the present application. All these changes and modifications are intended to be included within the scope of the present application as required by the appended claims.

[0074] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of the units is only a logical function division, and there may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed.

[0075] In the description provided herein, a large number of specific details are described. However, it is understood that the embodiments of the present application can be practiced without these specific details. In some instances, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this description.

[0076] Similarly, it should be understood that in order to streamline the present application and help understand one or more of the various inventive aspects, in the description of the exemplary embodiments of the present application, the various features of the present application are sometimes grouped together into a single embodiment, figure, or description thereof. However, the method of the present application should not be interpreted as reflecting the following intention: the claimed application requires more features than the features clearly stated in each claim. More specifically, as reflected in the corresponding claims, the inventive point is that the corresponding technical problem can be solved with features less than all the features of a single disclosed embodiment. Therefore, the claims following the specific embodiment are hereby explicitly incorporated into the specific embodiment, wherein each claim itself serves as a separate embodiment of the present application.

[0077] It will be understood by those skilled in the art that, except for mutually exclusive features, all features disclosed in this specification (including the accompanying claims, abstracts and drawings) and all processes or units of any method or device disclosed in this specification may be combined in any combination. Unless otherwise expressly stated, each feature disclosed in this specification (including the accompanying claims, abstracts and drawings) may be replaced by an alternative feature that provides the same, equivalent or similar purpose.

[0078] In addition, those skilled in the art will appreciate that, although some embodiments described herein include certain features included in other embodiments but not other features, the combination of features of different embodiments is meant to be within the scope of the present application and form different embodiments. For example, in the claims, any one of the claimed embodiments can be used in any combination.

[0079] It should be noted that the above-mentioned embodiments illustrate rather than limit the invention and that those skilled in the art will be able to design alternative embodiments without departing from the scope of the appended claims.

Claims

1. An RC-IGBT structure, characterized in that: include: A substrate, the substrate having a first main surface and a second main surface opposite to the first main surface, the first main surface and the second main surface being spaced apart in a vertical direction; a drift region of a first conductivity type, the drift region being disposed between the first main surface and the second main surface; A collector region of a second conductivity type, the collector region being disposed on a side of the drift region facing the first main surface, and a side of the collector region away from the drift region constituting at least a portion of the first main surface; a first trench gate extending from the second main surface to the first main surface into the drift region; A base region of a second conductivity type, the base region being disposed on a side of the drift region facing the second main surface and located on both sides of the first trench gate in a horizontal direction; A first emitter region of a first conductivity type, the first emitter region being disposed on a side of the base region facing the second main surface, and a side of the first emitter region away from the base region constituting a portion of the second main surface; a second emitter region of a second conductivity type, wherein the first emitter region is disposed on a side of the base region facing the second main surface and is located on a side of the first emitter region away from the first trench gate, and a side of the second emitter region away from the base region constitutes a part of the second main surface; a second trench gate, the second trench gate extending from the second main surface to the first main surface into the drift region; an anode region of a second conductivity type, the anode region being disposed on a side of the drift region facing the second main surface and being located on both sides of the second trench gate in a horizontal direction, and a side of the anode region away from the first main surface constituting a part of the second main surface; A channel stop region of the first conductivity type, the channel stop region being arranged on a side of the anode region away from the first trench gate, and a side of the channel stop region away from the first main surface constituting a part of the second main surface; Wherein, the anode region and the collector region are conductively connected via an external connecting line.

2. The RC-IGBT structure according to claim 1, characterized in that: The first trench gate and the second trench gate are connected through an inverter.

3. The RC-IGBT structure according to claim 1, characterized in that: The RC-IGBT structure further includes a first buffer zone of a first conductivity type, the first buffer zone being located between the anode region and the drift region and located on a side of the second trench gate facing the first trench gate; The doping concentration of the first buffer region is greater than the doping concentration of the drift region.

4. The RC-IGBT structure according to claim 1, characterized in that: The RC-IGBT structure further includes a carrier storage region of a first conductivity type, wherein the carrier storage region is located between the base region and the drift region; The doping concentration of the carrier storage region is greater than the doping concentration of the drift region.

5. The RC-IGBT structure according to claim 1, characterized in that: The RC-IGBT structure further includes a terminal structure located at least partially between the anode region and the base region.

6. The RC-IGBT structure according to claim 5, characterized in that: The terminal structure includes at least one of a field plate, a field limiting ring, a JTE and a VLD.

7. The RC-IGBT structure according to claim 1, characterized in that: The RC-IGBT structure further includes a second buffer zone of the first conductivity type, the second buffer zone being located between the drift region and the collector region; The doping concentration of the second buffer region is greater than the doping concentration of the drift region.

8. The RC-IGBT structure according to claim 1, characterized in that: The first trench gate comprises a first gate trench extending from the second main surface to the first main surface to the drift region, a first gate dielectric layer located on an inner surface of the first gate trench, and a first polysilicon gate located on a side of the first gate dielectric layer away from the inner surface of the first gate trench; The second trench gate includes a second gate trench extending from the second main surface to the first main surface to the drift region, a second gate dielectric layer located on the inner surface of the second gate trench, and a second polysilicon gate located on a side of the second gate dielectric layer away from the inner surface of the second gate trench.

9. The RC-IGBT structure according to any one of claims 1 to 8, characterized in that: The first conductivity type is N type; The second conductivity type is P type.

10. A semiconductor device, characterized in that: The invention comprises the RC-IGBT structure according to any one of claims 1 to 9.

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