Gate commutated thyristor and semiconductor device
By increasing the concentration of the doped region in the gate commutation thyristor, the problem of poor shutdown capability of the gate commutation thyristor in existing GCT chips is solved, and higher current shutdown capability and lower cathode heavy trigger risk is achieved.
Patent Information
- Application Number
- CN202520622083.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-03
- Publication Date
- 2025-05-27
- Estimated Expiration
- 2035-04-03
AI Technical Summary
In existing GCT chips, the shutdown capability of the gate converter thyristor is poor, and there is a large risk of cathode heavy triggering caused by dynamic avalanche during the shutdown process.
A gate commutation thyristor is designed, including a first base region, a second base region, a third base region and a first emission region that are stacked in sequence, and also includes at least two doping regions located in the third base region and in the second base region. The doping concentration of the doping region is greater than the doping concentration of the second base region and the third base region, ensuring that the resistance below the gate is smaller, and thus improving the current shutdown capability.
By increasing the concentration of the doped region, the voltage drop between the gate and cathode is reduced, the current shutdown capability of the device is improved, and the risk of cathode heavy triggering is reduced.
Smart Images
Figure CN222916503U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of semiconductor technology, and more particularly, to a gate commutated thyristor and a semiconductor device. Background Art
[0002] A gate commutated thyristor (GCT) is a current fully controlled high-power semiconductor device in the field of power electronics. Its conduction characteristics are like those of a thyristor, with low on-state losses. Its turn-off characteristics are like those of a transistor, so it has the characteristics of low on-state losses, large surge current, fast turn-off speed, and large power capacity. GCTs are usually used in some power-intensive electrical devices, such as heavy industry core equipment like metallurgical mill drive systems, ship drive systems, grid energy quality control devices, and high-voltage transmission commutation devices. In existing GCT chips, the turn-off ability of the gate commutated thyristor is poor, and there is a risk of cathode re-triggering caused by large dynamic avalanche during the turn-off process. Summary of the Utility Model
[0003] The main object of the present application is to provide a gate commutated thyristor and a semiconductor device to solve the problem of poor turn-off ability of the gate commutated thyristor in existing GCT chips.
[0004] To achieve the above object, according to one aspect of the present application, there is provided a gate commutated thyristor, including: a first base region; a second base region located on the surface of the first base region, the doping type of the second base region being different from that of the first base region; a third base region located on the surface of the second base region away from the first base region, the doping type of the third base region being the same as that of the second base region; a first emitter region located on the side of the third base region away from the first base region, the doping type of the first emitter region being the same as that of the first base region; at least two doped regions, the doped regions being at least located in the third base region and the second base region, the doped regions not being in contact with the first emitter region, the doping type of the doped regions being the same as that of the second base region, the doping concentration of the doped regions being greater than the doping concentration of the second base region, and the doping concentration of the doped regions being greater than the doping concentration of the third base region.
[0005] Optionally, the doping concentration of the third base region is greater than the doping concentration of the second base region, and the first emitter region has a convex structure.
[0006] Optionally, the gate commutated thyristor further includes: a fourth base region located on a surface of the third base region away from the first base region, the doping type of the fourth base region being the same as that of the second base region, the doping concentration of the fourth base region being less than that of the third base region, the first emitter region covering a part of the surface of the fourth base region away from the first base region, and the doped region being located in the fourth base region, the third base region, and the second base region.
[0007] Optionally, the gate commutated thyristor further includes: a cathode electrode located on a surface of the first emitter region away from the first base region; and at least two gate electrodes respectively located on at least a part of the surface of the doped region away from the first base region.
[0008] Optionally, the gate commutated thyristor further includes: a second emitter region located on a side of the first base region away from the second base region, the doping type of the second emitter region being different from that of the first emitter region.
[0009] Optionally, the gate commutated thyristor further includes: an anode electrode located on a surface of the second emitter region away from the first base region.
[0010] Optionally, the gate commutated thyristor further includes: a buffer layer located between the second emitter region and the first base region, the doping type of the buffer layer being the same as that of the first base region.
[0011] Optionally, the doping concentration of the first emitter region is 1e19 cm -3 ~5e21 cm -3 .
[0012] Optionally, the doping concentration of the doped region is a Gaussian distribution in a first direction, the doping concentration of a surface of the doped region away from the first base region being the peak value, and the doping concentration of the surface of the doped region away from the first base region being 1e18 cm -3 ~1e19 cm -3 , and the first direction is a direction parallel to the thickness of the first base region.
[0013] According to another aspect of the present application, a semiconductor device is provided, including any one of the gate commutated thyristors described above.
[0014] Applying the technical solution of the present application, the gate commutated thyristor includes a first base region, a second base region, a third base region, and a first emitter region stacked in sequence, and further includes at least two doped regions located in the third base region and the second base region. Among them, the doping type of the first base region is different from that of the second base region, the doping types of the third base region and the doped regions are the same as that of the second base region, the doping type of the first emitter region is the same as that of the first base region, and the doping concentration of the doped regions is greater than the doping concentrations of the second base region and the third base region. Compared with the problem of poor turn-off ability of the gate commutated thyristor in the existing GCT chips, in the present application, the doped regions are located in the third base region and the second base region, and the concentration of the doped regions is greater than that of the third base region and the second base region, ensuring a smaller resistance under the gate, thereby ensuring a smaller voltage drop between the gate and the cathode during the current turn-off process, and further ensuring a higher current turn-off ability of the device. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The accompanying drawings forming a part of this application are used to provide a further understanding of the application. The schematic embodiments and descriptions thereof of the application are used to explain the application and do not constitute an improper limitation to the application. In the drawings:
[0016] Figure 1 FIG. shows a schematic cross-sectional structure diagram of a gate commutated thyristor provided by an embodiment of the present application;
[0017] Figure 2 FIG. shows a schematic cross-sectional structure diagram of another gate commutated thyristor provided by an embodiment of the present application.
[0018] Among them, the above-mentioned drawings include the following reference numerals:
[0019] 10. First base region; 11. Second base region; 12. Third base region; 13. First emitter region; 14. Doped region; 15. Fourth base region; 16. Cathode electrode; 17. Gate electrode; 18. Second emitter region; 19. Anode electrode. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0020] It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present application belongs.
[0021] Note that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly dictates otherwise, the singular forms are also intended to include the plural forms. In addition, it should be understood that when the terms "comprises" and / or "comprising" are used in this specification, they specify the presence of the stated features, steps, operations, devices, components, and / or combinations thereof.
[0022] It should be understood that when an element (such as a layer, film, region, or substrate) is described as being "on" another element, the element can be directly on the other element or there can also be intervening elements. Also, in the specification and claims, when an element is described as being "connected" to another element, the element can be "directly connected" to the other element or "connected" to the other element through a third element.
[0023] As introduced in the background art, the turn-off ability of the gate-commutated thyristor in the existing GCT chip is poor. To solve the above problems, embodiments of the present application provide a gate-commutated thyristor and a semiconductor device.
[0024] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application.
[0025] Embodiments of the present application provide a gate-commutated thyristor, as Figure 1 and Figure 2 shown, comprising:
[0026] A first base region 10;
[0027] A second base region 11, located on the surface of the first base region 10, and the doping type of the second base region 11 is different from that of the first base region 10;
[0028] A third base region 12, located on the surface of the second base region 11 away from the first base region 10, and the doping type of the third base region 12 is the same as that of the second base region 11;
[0029] A first emitter region 13, located on the side of the third base region 12 away from the first base region 10, and the doping type of the first emitter region 13 is the same as that of the first base region 10;
[0030] At least two doped regions 14, the above-mentioned doped regions 14 are at least located in the above-mentioned third base region 12 and the above-mentioned second base region 11, the above-mentioned doped regions 14 are not in contact with the above-mentioned first emitter region 13, the doping type of the above-mentioned doped regions 14 is the same as that of the above-mentioned second base region 11, the doping concentration of the above-mentioned doped regions 14 is greater than the doping concentration of the above-mentioned second base region 11, and the doping concentration of the above-mentioned doped regions 14 is greater than the doping concentration of the above-mentioned third base region 12.
[0031] In the above embodiment, the gate commutated thyristor includes a first base region, a second base region, a third base region, and a first emitter region stacked in sequence, and further includes at least two doped regions located in the third base region and the second base region. Among them, the doping type of the first base region is different from that of the second base region, the doping types of the third base region and the doped regions are the same as that of the second base region, the doping type of the first emitter region is the same as that of the first base region, and the doping concentration of the doped regions is greater than the doping concentrations of the second base region and the third base region. Compared with the problem of poor turn-off ability of the gate commutated thyristor in the existing GCT chip, in the present application, the doped regions are located in the third base region and the second base region, and the concentration of the doped regions is greater than that of the third base region and the second base region, ensuring that the resistance under the gate is small, thereby ensuring that the voltage drop between the gate and the cathode during the current turn-off process is small, and further ensuring that the device has a high current turn-off ability.
[0032] In the embodiment of the present application, the doping types of the above-mentioned first base region and the above-mentioned first emitter region are N-type, and the doping types of the above-mentioned second base region, the above-mentioned third base region, and the above-mentioned doped regions are P-type. Specifically, the doped regions provided in the present application can reduce the voltage drop between the P-base region under the gate and the cathode during the current turn-off process.
[0033] Specifically, the above-mentioned first base region of the present application is equivalent to the substrate. Specifically, as Figure 1 and Figure 2 shown, the two doped regions 14 are arranged at intervals in the second direction, and the second direction is the direction perpendicular to the thickness of the first base region 10.
[0034] In the embodiment of the present application, the material of the first base region can be single crystal silicon or silicon carbide, and the present application does not make specific limitations thereon.
[0035] Specifically, the doping elements of the first base region and the first emitter region can be phosphorus (P), arsenic (As), antimony (Sb), etc., and the doping elements of the second base region, the third base region, and the doped regions can be boron (B), aluminum (Al), etc. In the actual application process, those skilled in the art can flexibly select appropriate doping elements according to actual needs, and the present application does not make specific limitations thereon.
[0036] In an exemplary embodiment, as Figure 1 and Figure 2As shown, the doping concentration of the above-mentioned third base region 12 is greater than that of the above-mentioned second base region 11, and the above-mentioned first emitter region 13 has a boss structure. In this embodiment, the doping concentration of the third base region is greater than that of the second base region, ensuring that the J3 junction (i.e., the PN junction formed by the third base region and the first emitter region) has a relatively large reverse breakdown voltage, thereby increasing the cathode retrigger current threshold and further enhancing the turn-off ability of the device.
[0037] In some other exemplary embodiments, such as Figure 1 and Figure 2 shown, the above-mentioned gate commutated thyristor further includes: a fourth base region 15, located on the surface of the above-mentioned third base region 12 away from the above-mentioned first base region 10. The doping type of the above-mentioned fourth base region 15 is the same as that of the above-mentioned second base region 11. The doping concentration of the above-mentioned fourth base region 15 is less than that of the above-mentioned third base region 12. The above-mentioned first emitter region 13 covers a part of the surface of the above-mentioned fourth base region 15 away from the above-mentioned first base region 10. The above-mentioned doping region 14 is located in the above-mentioned fourth base region 15, the above-mentioned third base region 12, and the above-mentioned second base region 11. In this embodiment, the fourth base region is located on the surface of the third base region away from the first base region, further reducing the voltage drop between the P base region under the gate and the cathode during the current turn-off process, which helps to further improve the current turn-off ability of the thyristor and ensures the more reliable operation of the device.
[0038] In the embodiments of the present application, the doping type of the above-mentioned fourth base region is P-type.
[0039] Specifically, the doping element of the fourth base region can be boron (B), aluminum (Al), etc., and the present application does not make specific limitations thereto.
[0040] In some alternative solutions, such as Figure 1 and Figure 2 shown, the above-mentioned gate commutated thyristor further includes: a cathode electrode 16, located on the surface of the above-mentioned first emitter region 13 away from the above-mentioned first base region 10; at least two gate electrodes 17, each corresponding to at least a part of the surface of the above-mentioned doping region 14 away from the above-mentioned first base region 10. In this embodiment, this design of multiple gate electrodes can achieve a more uniform current distribution, reduce the risk of local overheating, and further improve the reliability and service life of the thyristor.
[0041] Specifically, the materials of the cathode electrode and the gate electrode can be aluminum (Al), copper (Cu), nickel (Ni), tungsten (W), silver (Ag), etc. In the actual application process, those skilled in the art can flexibly select the materials of the cathode electrode and the gate electrode according to actual needs, and the present application does not make specific limitations thereto.
[0042] Specifically, the gate electrode can be located on a partial surface of the doped region away from the first base region, or can be located on the entire surface of the doped region away from the first base region. This application does not make specific limitations in this regard.
[0043] In other embodiments, such as Figure 1 and Figure 2 shown, the above-mentioned gate commutated thyristor further includes: a second emitter region 18, located on a side of the first base region 10 away from the second base region 11, and the doping type of the second emitter region 18 is different from that of the first emitter region 13. In this embodiment, by providing a second emitter region on the other side of the first base region and making it have a different doping type, the injection and extraction of carriers can be more effectively balanced during the on and off processes of the device, thereby improving the current control ability and switching speed of the device.
[0044] In the embodiment of this application, the doping type of the above-mentioned second emitter region is P-type.
[0045] Specifically, the doping element of the second doped region can be boron (B), aluminum (Al), etc. This application does not make specific limitations in this regard. The second emitter region can be prepared by ion implantation, diffusion, epitaxy or chemical vapor deposition.
[0046] In some other alternative solutions, such as Figure 1 and Figure 2 shown, the above-mentioned gate commutated thyristor further includes: an anode electrode 19, located on a surface of the second emitter region 18 away from the first base region 10.
[0047] Specifically, the material of the anode electrode can be aluminum (Al), copper (Cu), nickel (Ni), tungsten (W), silver (Ag), etc. In the actual application process, those skilled in the art can flexibly select the material of the anode electrode according to actual needs. This application does not make specific limitations in this regard.
[0048] In some other alternative solutions, the above-mentioned gate commutated thyristor further includes: a buffer layer, located between the second emitter region and the first base region, and the doping type of the buffer layer is the same as that of the first base region. In this embodiment, the buffer layer can modulate the electric field distribution, avoid complete depletion of the first base region under high voltage, and prevent punch-through breakdown between the first emitter region and the second emitter region, thereby improving the breakdown voltage and withstand voltage performance of the device.
[0049] In the embodiment of this application, the doping type of the above-mentioned buffer layer is N-type.
[0050] Specifically, the doping element of the buffer layer can be phosphorus (P), arsenic (As), antimony (Sb), selenium (Se), sulfur (S), etc. In the actual manufacturing process, those skilled in the art can flexibly select a suitable buffer layer material according to actual needs, and this application does not make specific limitations thereto. The buffer layer can be prepared by ion implantation combined with high-temperature diffusion.
[0051] In an exemplary embodiment, as Figure 1 and Figure 2 shown, the doping concentration of the above-mentioned first emitter region 13 is 1e19 cm -3 ~5e21 cm -3 .
[0052] In an exemplary embodiment, as Figure 1 and Figure 2 shown, the doping concentration of the above-mentioned doping region 14 is Gaussian-distributed in the first direction, the doping concentration on the surface of the above-mentioned doping region 14 far from the above-mentioned first base region 10 is the peak value, and the doping concentration on the surface of the above-mentioned doping region 14 far from the above-mentioned first base region 10 is 1e18 cm -3 ~1e19 cm -3 , and the above-mentioned first direction is the direction parallel to the thickness of the above-mentioned first base region 10.
[0053] Specifically, as Figure 1 and Figure 2 shown, the thickness of the doping region 14 is greater than the thickness of the third base region 12, and the doping concentration of the doping region 14 located in the second base region 11 is greater than 1e16 cm -3 .
[0054] In one embodiment, as Figure 1 shown, the doping concentration of the third base region 12 is Gaussian-distributed in the first direction, the upper surface of the third base region 12 (i.e., the surface far from the first base region 10) is the peak value, and the doping concentration on the upper surface of the third base region 12 is 1e17 cm -3 ~5e17 cm -3 , the doping concentration on the lower surface of the third base region 12 (i.e., the interface between the third base region 12 and the second base region 11) is 3e14 cm -3 ~1e15 cm -3 , the thickness of the third base region 12 is 50 μm~80 μm; the doping concentration of the second base region 11 is Gaussian-distributed in the first direction, the upper surface of the second base region 11 (i.e., the surface far from the first base region 10) is the peak value, and the doping concentration on the upper surface of the second base region 11 is 5e14 cm -3 ~5e15 cm -3 , and the sum of the thicknesses of the second base region 11 and the third base region 12 is 100 μm~160 μm.
[0055] In one embodiment, asFigure 2 As shown, the doping concentration of the fourth base region 15 is a Gaussian distribution in the first direction, the upper surface of the fourth base region 15 (i.e., the surface far from the first base region 10) is the peak, and the doping concentration of the upper surface of the fourth base region 15 is 5e14 cm -3 ~5e15 cm -3 , the thickness of the fourth base region 15 is 15 μm to 25 μm; the doping concentration of the third base region 12 is a Gaussian distribution in the first direction, the peak of the doping concentration of the third base region 12 is in the central region of the third base region 12, and the peak of the doping concentration of the third base region 12 is 1e17 cm -3 ~1e18 cm -3 , the doping concentration of the lower surface of the third base region 12 (i.e., the interface between the third base region 12 and the second base region 11) is 1e15 cm -3 ~1e16 cm -3 , the thickness of the third base region 12 is 5 μm to 25 μm; the doping concentration of the second base region 11 is a Gaussian distribution in the first direction, the upper surface of the second base region 11 (i.e., the surface far from the first base region 10) is the peak, and the doping concentration of the upper surface of the second base region 11 is 5e14 cm -3 ~5e15 cm -3 , and the sum of the thicknesses of the second base region 11, the third base region 12, and the fourth base region 15 is 100 μm to 160 μm.
[0056] In one embodiment, as Figure 2 shown, the fourth base region 15 is uniformly doped, the doping concentration of the fourth base region 15 is 5e14 cm -3 ~5e15 cm -3 , the thickness of the fourth base region 15 is 15 μm to 25 μm; the third base region 12 is uniformly doped, the doping concentration of the third base region 12 is 1e17 cm -3 ~1e18 cm -3 , the thickness of the third base region 12 is 5 μm to 25 μm; the doping concentration of the second base region 11 is a Gaussian distribution in the first direction, the upper surface of the second base region 11 (i.e., the surface far from the first base region 10) is the peak, and the doping concentration of the upper surface of the second base region 11 is 3e14 cm -3 ~1e15 cm -3 , and the thickness of the second base region 11 is 50 μm to 100 μm.
[0057] The embodiment of the present application also provides a semiconductor device, including any of the above-mentioned gate-commutated thyristors.
[0058] In the above embodiments, the semiconductor device includes a gate-commutated thyristor. The gate-commutated thyristor includes a first base region, a second base region, a third base region, and a first emitter region stacked in sequence, and further includes at least two doped regions located in the third base region and the second base region. The doping type of the first base region is different from that of the second base region. The doping types of the third base region and the doped regions are the same as that of the second base region. The doping type of the first emitter region is the same as that of the first base region. The doping concentration of the doped regions is greater than the doping concentrations of the second base region and the third base region. Compared with the problem of poor turn-off ability of the gate-commutated thyristor in the existing GCT chip, in this application, the doped regions are located in the third base region and the second base region, and the concentration of the doped regions is greater than that of the third base region and the second base region, ensuring a smaller resistance under the gate, thereby ensuring a smaller voltage drop between the gate and the cathode during the current turn-off process, and further ensuring a higher current turn-off ability of the device.
[0059] From the above description, it can be seen that the above embodiments of this application achieve the following technical effects:
[0060] In the gate-commutated thyristor of this application, the gate-commutated thyristor includes a first base region, a second base region, a third base region, and a first emitter region stacked in sequence, and further includes at least two doped regions located in the third base region and the second base region. The doping type of the first base region is different from that of the second base region. The doping types of the third base region and the doped regions are the same as that of the second base region. The doping type of the first emitter region is the same as that of the first base region. The doping concentration of the doped regions is greater than the doping concentrations of the second base region and the third base region. Compared with the problem of poor turn-off ability of the gate-commutated thyristor in the existing GCT chip, in this application, the doped regions are located in the third base region and the second base region, and the concentration of the doped regions is greater than that of the third base region and the second base region, ensuring a smaller resistance under the gate, thereby ensuring a smaller voltage drop between the gate and the cathode during the current turn-off process, and further ensuring a higher current turn-off ability of the device.
[0061] The above is only the preferred embodiment of this application and is not used to limit this application. For those skilled in the art, this application can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this application shall be included in the protection scope of this application.
Claims
1. A gate-commutated thyristor, characterized in that: include: first base region; a second base region, located on the surface of the first base region, wherein the doping type of the second base region is different from the doping type of the first base region; a third base region, located on a surface of the second base region away from the first base region, the doping type of the third base region being the same as the doping type of the second base region, and the doping concentration of the third base region being greater than the doping concentration of the second base region; A first emitter region is located at a side of the third base region away from the first base region, and the doping type of the first emitter region is the same as the doping type of the first base region; At least two doping regions, the doping regions are located at least in the third base region and the second base region, the doping regions are not in contact with the first emitter region, the doping type of the doping regions is the same as that of the second base region, the doping concentration of the doping regions is greater than the doping concentration of the second base region, and the doping concentration of the doping regions is greater than the doping concentration of the third base region.
2. The gate-commutated thyristor according to claim 1, characterized in that: The first emitting area has a boss structure.
3. The gate-commutated thyristor according to claim 1, characterized in that: The gate-commutated thyristor further comprises: A fourth base region is located on a surface of the third base region away from the first base region, the doping type of the fourth base region is the same as the doping type of the second base region, the doping concentration of the fourth base region is less than the doping concentration of the third base region, the first emitter region covers a portion of the surface of the fourth base region away from the first base region, and the doping region is located in the fourth base region, the third base region and the second base region.
4. The gate-commutated thyristor according to any one of claims 1 to 3, characterized in that: The gate-commutated thyristor further comprises: A cathode electrode, located on a surface of the first emitter region away from the first base region; At least two gate electrodes are located in a one-to-one correspondence at least on a portion of the surface of the doped region away from the first base region.
5. The gate-commutated thyristor according to claim 4, characterized in that: The gate-commutated thyristor further comprises: The second emitter region is located at a side of the first base region away from the second base region, and the doping type of the second emitter region is different from the doping type of the first emitter region.
6. The gate-commutated thyristor according to claim 5, characterized in that: The gate-commutated thyristor further comprises: An anode electrode is located on a surface of the second emitter region away from the first base region.
7. The gate-commutated thyristor according to claim 6, characterized in that: The gate-commutated thyristor further comprises: A buffer layer is located between the second emitter region and the first base region, and a doping type of the buffer layer is the same as a doping type of the first base region.
8. The gate-commutated thyristor according to any one of claims 1 to 3, characterized in that: The doping concentration of the first emission region is 1e19cm -3 ~5e21cm -3 .
9. The gate-commutated thyristor according to any one of claims 1 to 3, characterized in that: The doping concentration of the doping region is Gaussian in the first direction, the doping concentration of the surface of the doping region away from the first base region is a peak value, and the doping concentration of the surface of the doping region away from the first base region is 1e18 cm -3 ~1e19cm -3 , the first direction is a direction parallel to the thickness of the first base region.
10. A semiconductor device, characterized in that: The invention comprises the gate-commutated thyristor according to any one of claims 1 to 9.