Electrode structure and chip

Abstract

The present application provides an electrode structure and a chip. The electrode structure includes: a body portion, which includes a first surface, a second surface, and a plurality of hollowed-out regions penetrating the first surface and the second surface. The first surface is opposite to the second surface. The plurality of hollowed-out regions include a first hollowed-out region and a second hollowed-out region. The distance between the first hollowed-out region and the second hollowed-out region is greater than half of the equivalent radius, and the equivalent radius is the ratio of twice the area of the first surface to the perimeter of the first surface. The material of the body portion includes an inorganic non-metallic solid material and a metallic material; a plurality of conductive portions, each of which fills the hollowed-out region correspondingly. The conductive portion includes a metallic material. The present application solves the problems that in existing power devices, the conductivity of the electrodes is poor and the current distribution inside the electrodes is uneven, thus affecting the performance of the devices.

Description

Technical Field

[0001] This application relates to the field of semiconductor technology, and in particular, to an electrode structure and a chip. Background Art

[0002] In existing power devices, the electrodes have good heat dissipation performance, but poor electrical conductivity, and there is a phenomenon of uneven current distribution inside the electrodes, which affects the device performance. Summary of the Invention

[0003] The main purpose of this application is to provide an electrode structure and a chip to solve the problem that the electrodes in existing power devices have poor electrical conductivity and uneven current distribution inside the electrodes, thus affecting the device performance.

[0004] To achieve the above object, according to one aspect of this application, an electrode structure is provided. The electrode structure includes: a body portion, including a first surface, a second surface, and a plurality of hollow regions penetrating the first surface and the second surface. The first surface and the second surface are opposite to each other. Among the plurality of hollow regions, there are a first hollow region and a second hollow region. The distance between the first hollow region and the second hollow region is greater than half of the equivalent radius, and the equivalent radius is the ratio of twice the area of the first surface to the perimeter of the first surface. The material of the body portion includes an inorganic non-metallic solid material and a metal material; a plurality of conductive portions, each of the conductive portions fills the hollow region correspondingly, and the conductive portion includes a metal material.

[0005] Optionally, the surface of the electrode structure has a plurality of regions, the volumes of the regions are equal, and each region includes at least one end face of the conductive portion. The distance between the centroid of the region and the equivalent centroid of all the end faces of the conductive portions included in the region is not greater than one-third of the equivalent radius.

[0006] Optionally, each region includes a first boundary line and a second boundary line. The first boundary line and the second boundary line intersect at the centroid of the surface of the electrode structure, and one end point of the first boundary line and one end point of the second boundary line are both the centroid of the surface of the electrode structure.

[0007] Optionally, the volumes of the conductive portions corresponding to all the end faces included in any two regions are equal.

[0008] Optionally, the volume of all the conductive portions included in the electrode structure Satisfies: , represents the ratio of the equivalent conductivity required for the electrode structure of the same size to the conductivity of standard annealed oxygen-free copper. represents the conductivity of the material of the conductive part, represents the conductivity of standard annealed oxygen-free copper, represents the total volume of the electrode structure.

[0009] Optionally, the plurality of conductive parts include at least one of the following: a columnar conductive part and an annular conductive part.

[0010] Optionally, any two of the conductive parts are spaced apart and not connected, and the i-th conductive part satisfies: , where represents the th end face of the th conductive part and the th end face of the th conductive part, and the minimum distance between the two end faces, represents the th end face of the

[0011] Optionally, the number of the columnar conductive parts is 4 to 36.

[0012] Optionally, adjacent two of the conductive parts are connected, and the shape formed by at least part of the conductive parts is one of the following: a grid shape and a mesh shape.

[0013] According to another aspect of the present application, a chip is provided, including: a chip body; at least one of any of the above electrode structures, and one electrode structure is located on one side of the chip body.

[0014] Applying the technical solution of the present application, the electrode structure includes a main body portion and a plurality of conductive portions. Among them, the main body portion includes a first surface, a second surface, and a plurality of hollow regions penetrating the first surface and the second surface. Each conductive portion correspondingly fills the hollow region. The material of the main body portion includes an inorganic non-metallic solid material and a metal material, and the material of the conductive portion includes a metal material. Among the plurality of hollow regions, there are a first hollow region and a second hollow region, and the distance between the first hollow region and the second hollow region is greater than half of the equivalent radius. Compared with the problems in existing power devices where the conductivity of the electrode is poor and the current distribution inside the electrode is uneven, thus affecting the device performance, the electrode structure in the present application includes a main body portion and a plurality of conductive portions. The main body portion includes a plurality of hollow regions, and each conductive portion correspondingly fills the hollow region, that is, a metal conductive channel is introduced into the main body portion, creating a low-resistance path that allows current to flow freely in these paths without being affected by the low conductivity of the material of the main body portion. This is equivalent to implanting a high-conductive network in a low-conductive material, ensuring good conductivity of the electrode, and thus ensuring a low on-state voltage drop of the device. In addition, there are a plurality of hollow regions, and the distance between the first hollow region and the second hollow region among the plurality of hollow regions is greater than half of the equivalent radius, ensuring a relatively uniform distribution of the conductive portions in the electrode structure, and thus ensuring a relatively uniform current distribution inside the electrode, suppressing the problems of uneven local Joule heat effect and uneven thermal stress of the device, and ensuring good reliability 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 shows a schematic diagram of an electrode structure provided according to an embodiment of the present application;

[0017] Figure 2 shows a schematic diagram of another electrode structure provided according to an embodiment of the present application;

[0018] Figure 3 shows a schematic diagram of yet another electrode structure provided according to an embodiment of the present application;

[0019] Figure 4 (a)-(b) show schematic diagrams of an optional electrode structure provided according to an embodiment of the present application;

[0020] Figure 5 shows a schematic diagram of yet another optional electrode structure provided according to an embodiment of the present application;

[0021] Figure 6(a) - 6(d) show schematic diagrams of each region in an electrode structure provided according to an embodiment of the present application;

[0022] Figure 7 show a schematic diagram of a specific electrode structure provided according to an embodiment of the present application.

[0023] Among them, the above-mentioned drawings include the following reference numerals:

[0024] 10. Electrode structure; 101. Body part; 1011. First surface; 102. Conductive part; 11. Region; 12. Conductive part set. Detailed implementation manners

[0025] It should be noted that the following detailed descriptions are all illustrative and are intended to provide further explanations 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.

[0026] It should be noted that the terms used herein are only for describing specific implementation manners and are not intended to limit the exemplary implementation manners according to the present application. As used herein, unless otherwise clearly specified in the context, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0027] 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 an intermediate element. Moreover, in the specification and claims, when an element is described as "connected" to another element, the element can be "directly connected" to the other element, or "connected" to the other element through a third element.

[0028] For the convenience of description, the following explains some nouns or terms related to the embodiments of the present application:

[0029] As introduced in the background art, the conductivity of the electrodes in existing power devices is poor and the current distribution inside the electrodes is uneven, thus affecting the performance of the devices. To solve the above problems, the embodiments of the present application provide an electrode structure and a chip.

[0030] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present invention.

[0031] The embodiments of the present application provide an electrode structure, as Figures 1 to 5 shown, the above-mentioned electrode structure 10 includes:

[0032] The main body part 101 includes a first surface 1011, a second surface (not labeled), and a plurality of hollow areas (not labeled) penetrating through the first surface 1011 and the second surface. The first surface 1011 is opposite to the second surface. Among the plurality of hollow areas, there are a first hollow area (not labeled) and a second hollow area (not labeled). The distance between the first hollow area and the second hollow area is greater than half of the equivalent radius, and the equivalent radius is the ratio of twice the area of the first surface 1011 to the perimeter of the first surface 1011. The material of the main body part 101 includes an inorganic non-metallic solid material and a metallic material;

[0033] Specifically, "the distance between the first hollow area and the second hollow area is greater than half of the equivalent radius" means that among the plurality of hollow areas, the distance between the two hollow areas with the farthest distance is greater than half of the equivalent radius.

[0034] Specifically, if the inorganic non-metallic solid material is diamond and the metallic material is copper or aluminum, then the material of the main body part can be a copper-diamond composite material or an aluminum-diamond composite material.

[0035] A plurality of conductive parts 102, and each of the conductive parts 102 fills the hollow area correspondingly one by one. The conductive part includes a metallic material.

[0036] Specifically, the material of the conductive part includes but is not limited to silver, copper, aluminum, and molybdenum.

[0037] Specifically, the volume of the conductive part is the same as that of the hollow area.

[0038] Through the above embodiments, the electrode structure includes a body portion and a plurality of conductive portions. Among them, the body portion includes a first surface, a second surface, and a plurality of hollowed-out regions connecting the first surface and the second surface. Each conductive portion correspondingly fills a hollowed-out region. The material of the body portion includes an inorganic non-metallic solid material and a metal material, and the material of the conductive portion includes a metal material. The plurality of hollowed-out regions include a first hollowed-out region and a second hollowed-out region, and the distance between the first hollowed-out region and the second hollowed-out region is greater than half of the equivalent radius. Compared with the problems in existing power devices where the conductivity of the electrode is poor and the current distribution inside the electrode is uneven, which affects the device performance, the electrode structure in this application includes a body portion and a plurality of conductive portions. The body portion includes a plurality of hollowed-out regions, and each conductive portion correspondingly fills a hollowed-out region, that is, a metal conductive channel is introduced into the body portion, creating a low-resistance path that allows current to flow freely in these paths without being affected by the low conductivity of the body portion material. This is equivalent to implanting a high-conductivity network in a low-conductivity material, ensuring good conductivity of the electrode and thus ensuring a low on-state voltage drop of the device. In addition, there are multiple hollowed-out regions, and the distance between the first hollowed-out region and the second hollowed-out region among the multiple hollowed-out regions is greater than half of the equivalent radius, ensuring a relatively uniform distribution of the conductive portions in the electrode structure, thus ensuring a relatively uniform current distribution inside the electrode, suppressing the problems of uneven local Joule heat effect and uneven thermal stress in the device, and ensuring good reliability of the device.

[0039] Specifically, the material of the body portion can also be silicon carbide, aluminum nitride, or boron nitride. The thermal conductivity of the material of the body portion is not less than 400 W / (m·K), which can further ensure good heat dissipation of the electrode structure, so that the Joule heat generated during the operation of the device can be dissipated faster and more effectively, thereby further improving the reliability of the device.

[0040] In the actual application process, those skilled in the art can flexibly select appropriate materials for the body portion and the conductive portion according to actual needs, and this application does not make specific restrictions on this.

[0041] It should be noted that there are three types of electrode designs: (1) Electrode design based on metal or alloy materials: High thermal conductivity metal materials represented by metals and their alloys such as copper, aluminum, silver, and molybdenum have superior electrical conductivity, good heat dissipation ability, and good machinability. Based on this type of metal material system, high thermal conductivity electrodes applicable to electronic devices such as IGCT (Integrated Gate-Commutated Thyristor) devices can be manufactured. The main defects of this technology are as follows: ① The upper limit of the thermal conductivity of metal materials is relatively low, unable to meet the heat dissipation requirements of high-power and large-capacity electronic devices. ② The thermal expansion coefficient of metal materials is usually relatively large, much larger than that of various semiconductor materials. If in direct contact with the chip, it will cause serious relative friction and result in device failure. ③ Poor chemical stability, prone to oxidation. (2) Electrode design based on non-metal materials: High thermal conductivity non-metal materials represented by diamond, silicon carbide, aluminum nitride, and boron nitride have superior heat dissipation ability and a thermal expansion coefficient compatible with semiconductor materials, and can be used to manufacture high thermal conductivity electrodes applicable to high-power and large-capacity electronic devices. The main defects of this technology are as follows: ① The electrical conductivity of non-metal materials is extremely poor and cannot meet the electrical conductivity requirements of electronic devices such as IGCT. ② The manufacturing cost of materials such as diamond is extremely high. (3) Electrode design based on metal-non-metal composite materials: Metal-non-metal composite materials represented by copper-diamond and aluminum-diamond significantly improve the thermal conductivity by randomly doping high thermal conductivity non-metal material particles in the metal matrix, have superior heat dissipation ability, and a thermal expansion coefficient compatible with semiconductor materials, and can be used to manufacture high thermal conductivity electrodes applicable to high-power and large-capacity electronic devices. The main defect of this technology is that when the volume fraction of non-metal particles is relatively high, the electrical conductivity of the metal-non-metal composite material deteriorates sharply.

[0042] It should be noted that the high thermal conductivity composite electrode materials (such as copper-diamond composite materials) used in packaging IGCT devices have poor electrical conductivity, resulting in the actual on-state voltage drop of the device being significantly higher than the designed value and unable to meet the engineering requirements. In order to solve the problem of poor electrical conductivity of the high thermal conductivity composite electrode materials and reduce the on-state voltage drop of the device, it is necessary to improve the design of the currently used high thermal conductivity composite electrode materials. Metal materials naturally have the advantage of high electrical conductivity. In this application, a metal conductive channel with a certain volume and penetrating the upper and lower surfaces of the electrode is added at a specified position inside the electrode, which can significantly improve the electrical conductivity of the electrode without affecting the thermal conductivity and thermal expansion characteristics. After adding the metal conductive channel, it is also necessary to ensure the uniformity of the current distribution inside the electrode, suppress the problems of local Joule heat effect and uneven thermal stress, and improve the reliability of the electronic device. For this purpose, this application further proposes a layout method for constructing the metal channel.

[0043] In an alternative solution, such as Figure 6As shown in FIGS. (a) - 6(d), the surface of the above - mentioned electrode structure 10 has a plurality of regions 11. The volumes of the respective regions 11 are equal. Each of the regions 11 includes the end face of at least one of the above - mentioned conductive parts (not shown). The distance between the centroid of the region 11 and the equivalent centroid of the end faces of all the conductive parts included in the region 11 is not greater than one - third of the above - mentioned equivalent radius. In this embodiment, the electrode surface is divided into a plurality of regions of equal volume, and the end face of at least one metal conductive part is included in each region. By adjusting the layout of the conductive parts, the equivalent centroid is made to approach the centroid of the region, reducing the distribution difference of current between different regions. This helps to further reduce the problem of uneven local Joule heat effect, and further reduces the risk of device failure.

[0044] In some embodiments, each of the above - mentioned regions includes a first boundary line and a second boundary line. The first boundary line and the second boundary line intersect at the centroid of the surface of the electrode structure, and one end point of the first boundary line and one end point of the second boundary line are both the centroid of the surface of the electrode structure. In this embodiment, the surface of the electrode structure is divided into a plurality of regions, each region is defined by a first boundary line and a second boundary line, and these two boundary lines intersect at the centroid of the electrode, which means that the distribution of the conductive parts in the electrode follows the symmetry principle, further reducing the local over - current phenomenon, further ensuring that the current distribution is more uniform, and further ensuring better device performance.

[0045] Specifically, the specific division method of the region is as follows: As Figure 6 shown in FIG. (a), the surface of the electrode structure 10 is circular, and each region 11 is a sector, and the sectors meet at the centroid of the surface of the electrode structure 10; as Figure 6 shown in FIGS. (b) and Figure 6 shown in FIG. (c), the surface of the electrode structure 10 is rectangular, and each region 11 is a rectangle or a triangle, and the rectangles or the triangles meet at the centroid of the surface of the electrode structure 10; as Figure 6 shown in FIG. (d), the surface of the electrode structure 10 is triangular, and each region 11 is a triangle, and the triangles meet at the centroid of the surface of the electrode structure 10. When the surface of the electrode structure is any other simply - connected shape, each region is divided in a similar manner, and the regions meet at the centroid of the surface of the electrode structure.

[0046] In one embodiment, as Figure 7As shown, the surface of the electrode structure 10 is circular, and each region 11 is a sector. The sectors meet at the centroid of the surface of the electrode structure 10. Each region 11 includes the end faces of three conductive parts 102, and the distance between the centroid of the end face of one of the conductive parts 102 in the region 11 and the centroids of the end faces of the other two conductive parts 102 is equal. In this case, the centroid of the region approximately coincides with the equivalent centroid of the end faces of all the conductive parts included in the region.

[0047] According to some other exemplary embodiments of the present application, the volumes of the conductive parts corresponding to the end faces of all the conductive parts included in any two of the above regions are equal. In this embodiment, the volume of the conductive part directly affects its conductivity, and thus affects the flow of current thereon. The fact that the volumes of the conductive parts corresponding to the end faces of all the conductive parts included in any two regions are equal further ensures the balance of the current distribution inside the electrode structure, further reduces the current concentration phenomenon caused by the volume difference of the conductive parts, and further reduces the risk of failure caused by thermal stress and local overheating, thereby further ensuring better device performance.

[0048] In some other alternative solutions of the present application, the volumes of all the conductive parts included in the above electrode structure Satisfy: , represents the ratio of the equivalent conductivity required for the above electrode structure to the conductivity of standard annealed oxygen-free copper under the same size, represents the conductivity of the material of the above conductive part, represents the conductivity of standard annealed oxygen-free copper, represents the total volume of the above electrode structure. In this embodiment, this formula can guide the selection of the volume of the conductive part in the design of the electrode structure, and further ensure better conductivity of the electrode structure.

[0049] Specifically, is the required conductivity grade of the electrode structure, and the unit is %IACS (International Annealed Copper Standard); is about 5.8×10 7 S / m.

[0050] Specifically, the volume of all the conductive parts included in the electrode structure can be calculated according to the required conductivity grade of the electrode structure.

[0051] In other embodiments, the plurality of the above-mentioned conductive parts include at least one of the following: a columnar conductive part and an annular conductive part. In this embodiment, the selection and layout of the columnar conductive part and the annular conductive part can further optimize the current conduction path and reduce the resistance. The cylindrical conductive part, due to its high surface area-to-volume ratio, is particularly suitable for application scenarios that require rapid heat dissipation, while the annular conductive part can provide a more uniform current distribution and is suitable for situations with high requirements for current distribution uniformity.

[0052] Specifically, the columnar conductive part can be a cylindrical conductive part, a prismatic conductive part, or other columnar conductive parts, and the present application does not make specific limitations thereto.

[0053] Specifically, in one electrode structure, all the conductive parts can be columnar conductive parts or annular conductive parts; or some of the conductive parts can be columnar conductive parts and the remaining conductive parts can be annular conductive parts.

[0054] Specifically, the shape of the conductive part can also be an irregular shape, such as a spiral shape. The spiral metal can form a spiral path inside the electrode structure, which helps to further evenly distribute the current.

[0055] According to some other exemplary embodiments of the present application, any two of the above-mentioned conductive parts are spaced apart and not connected, and the i-th above-mentioned conductive part satisfies: , where represents the minimum distance between the end face of the -th above-mentioned conductive part and the end face of the -th above-mentioned conductive part, represents the distance between the end face of the -th above-mentioned conductive part and the centroid of the surface of the above-mentioned electrode structure, represents the distance between the end face of the -th above-mentioned conductive part and the edge of the surface of the above-mentioned electrode structure, and R represents the above-mentioned equivalent radius. In this embodiment, by controlling the minimum distance between the end faces of the conductive parts and their distances from the center and edge of the electrode, the uniform distribution of the current path is further ensured, local overheating and current congestion are further avoided, and the stability of the device is further improved.

[0056] According to some other exemplary embodiments of the present application, the number of the columnar conductive parts is 4 to 36. In this embodiment, the increase in the number of conductive parts means more conductive paths, which helps to evenly distribute the current. However, it will also occupy more space, which may affect the proportion of the material of the main body part and the control of the thermal conductivity and the coefficient of thermal expansion. Therefore, selecting an appropriate number of conductive parts is the key to achieving the balance between high conductivity and high thermal conductivity of the electrode structure. Within the range of 4 to 36 conductive parts, the electrode structure can effectively disperse and carry the current, further improving the uniformity of the current distribution, while maintaining good thermal conductivity, further reducing the phenomenon of local overheating, and thus further improving the stability and reliability of the electronic device.

[0057] In one embodiment, the columnar conductive part is a cylindrical conductive part, the diameter of the cylindrical conductive part is 0.05 to 0.15 of the maximum width of the surface of the electrode structure, and the number of the cylindrical conductive parts is 4 to 36. In this embodiment, satisfying these two conditions simultaneously can further ensure that both the conductivity and the current distribution uniformity of the electrode structure are good.

[0058] In a specific embodiment, as Figure 1 shown, the electrode structure 10 is cylindrical, the diameter of the electrode structure 10 is 138 mm, the thickness of the electrode structure 10 is 5 mm, the shape of the conductive part 102 is cylindrical, the number of the conductive parts 102 is 9, the material of the conductive part 102 is molybdenum, and the diameter of the conductive part 102 is 10 mm. In the prior art, the axial equivalent conductivity of an electrode made of a copper-diamond composite material of the same size is on the order of 0.01% IACS. The equivalent conductivity of the electrode structure formed by embedding the cylindrical conductive part in the present application is on the order of 4% IACS, and the improvement effect can reach 400 times, which can meet the current-carrying capacity requirements of high-voltage and large-capacity IGCT devices.

[0059] Specifically, Figure 2 is a schematic diagram of an electrode structure with a ring-shaped conductive part.

[0060] In another specific embodiment, the electrode structure is cylindrical, the diameter of the electrode structure is 138 mm, the thickness of the electrode structure is 5 mm, the number of the cylindrical conductive parts is 25, the material of the cylindrical conductive part is molybdenum, and the diameter of the cylindrical conductive part is 10 mm. In this case, the electrode structure has a high conductivity.

[0061] In some further exemplary embodiments of the present application, adjacent ones of the above-mentioned conductive parts are connected, and at least a part of the shapes formed by the above-mentioned conductive parts are one of the following: grid-like and mesh-like. In this embodiment, the grid-like or mesh-like form forms a continuous conductive network, which is conducive to the smooth flow of current, reduces the additional loss of current between the conductive parts, and further improves the overall conductive performance of the electrode structure. For example, when the conductive parts form a grid-like layout, it can further ensure the uniform distribution of current in the horizontal and vertical directions, and further improve the performance of the device.

[0062] Specifically, if the shape formed by a plurality of conductive parts is grid-like, each side of the grid is a conductive part.

[0063] Specifically, in an electrode structure, the shapes formed by all the conductive parts can all be grid-like or mesh-like; or the shapes formed by some of the conductive parts can be grid-like, and the shapes formed by the remaining conductive parts can be mesh-like.

[0064] Specifically, if the shape formed by a plurality of conductive parts is mesh-like, and the part connecting adjacent two conductive parts does not penetrate the first surface and the second surface, then this part is not a conductive part, and the material of this part can be the same as the material of the conductive part.

[0065] Specifically, Figure 3 is a schematic diagram of another electrode structure. Figure 3 In, the shape of the conductive part set 12 (that is, the structure formed by all the conductive parts (not marked)) in the electrode structure 10 is grid-like.

[0066] Specifically, Figure 4 (a) - 4(b) is a schematic diagram of another electrode structure. Figure 4 (a) and Figure 4 (b), the shape of the conductive part set 12 (that is, the structure formed by all the conductive parts (not marked)) in the electrode structure 10 is mesh-like. Figure 4 (a) is a schematic diagram of the structure of the conductive part set, Figure 4 (b) is a schematic diagram of the structure of the electrode structure.

[0067] In one embodiment, an electrode structure includes a plurality of conductive parts, some of the conductive parts are spaced apart and not connected, and adjacent conductive parts among the remaining conductive parts are connected. The shapes of the non-connected conductive parts are columnar and / or annular, and the shapes formed by the connected conductive parts are grid-like and / or mesh-like.

[0068] Specifically, Figure 5 is a schematic diagram of another electrode structure. Figure 5 In, the shapes of the conductive parts 102 at different positions of the electrode structure 10 are different.

[0069] Specifically, the shape formed by multiple conductive parts can also be honeycomb-shaped, dendritic, etc., and the present application does not make specific limitations on this.

[0070] Specifically, the present application also provides the following 5 embodiments, as shown respectively in Figures 1 to 5 shown.

[0071] Embodiment 1: An electrode structure based on the layout of a metal column array (that is, any two conductive parts are spaced apart and not connected, and the conductive part is a cylindrical conductive part).

[0072] First, according to the formula , calculate the volume of all the conductive parts required in the electrode structure, and then arrange a plurality of metal columns (i.e., conductive parts) in the mold according to the layout requirements of the conductive parts (i.e., the current uniformity requirements), and the height of each metal column is sufficient to penetrate the upper and lower surfaces of the electrode structure; then fill the gaps between the plurality of metal columns with a high thermal conductivity material (such as copper-diamond, aluminum-diamond composite material, etc.), and realize the combination between the two through certain process means (such as infiltration process, sintering process, hot pressing process, deposition process, etc.); after forming, polish the surface of the electrode structure to meet the specified flatness and roughness requirements, so as to complete the preparation of the electrode structure.

[0073] It should be noted that there are no restrictions on the layout method and quantity of the plurality of metal columns, the size of the metal columns, the type and formula of the filled high thermal conductivity material, and the combination process between the metal columns and the high thermal conductivity material.

[0074] The experimental measurement results show that in a copper-diamond disc (i.e., the main body part) with a diameter of 138 mm and a thickness of 5 mm, 9 molybdenum columns (i.e., conductive parts) with a diameter of 10 mm that penetrate the upper and lower surfaces of the main body part are evenly embedded, and the axial equivalent conductivity of the disc can be increased from the 0.01% IACS level before embedding the molybdenum columns to the 4% IACS level, and the improvement effect can reach 400 times, which can meet the current-carrying capacity requirements of high-voltage and large-capacity IGCT devices.

[0075] Embodiment 2: An electrode structure based on the layout of a metal ring array (that is, any two conductive parts are spaced apart and not connected, and the conductive part is a ring-shaped conductive part).

[0076] First, according to the formula , calculate the volume of all the conductive parts required in the electrode structure, and then arrange multiple metal rings (i.e., conductive parts) in the mold according to the layout requirements of the conductive parts (i.e., the current uniformity requirements). The height of each metal ring is sufficient to penetrate the upper and lower surfaces of the electrode structure; then fill the gaps between the multiple metal rings with a high thermal conductivity material (such as copper-diamond, aluminum-diamond composite materials, etc.), and achieve the combination between the two through certain process means (such as infiltration process, sintering process, hot pressing process, deposition process, etc.); after forming, polish the surface of the electrode structure to meet the specified flatness and roughness requirements, thus completing the preparation of the electrode structure.

[0077] It should be noted that there are no restrictions on the layout method and quantity of the multiple metal rings, the size of the metal rings, the type and formula of the filled high thermal conductivity material, and the combination process between the metal rings and the high thermal conductivity material.

[0078] Example 3: Electrode structure based on a metal grid framework (i.e., connected between two adjacent conductive parts).

[0079] First, according to the formula , calculate the volume of all the conductive parts required in the electrode structure, and then arrange the metal grid framework evenly in the mold according to the layout requirements of the conductive parts (i.e., the current uniformity requirements). The height of the metal grid framework is sufficient to penetrate the upper and lower surfaces of the electrode structure; then fill the gaps between the metal grid framework with a high thermal conductivity material (such as copper-diamond, aluminum-diamond composite materials, etc.), and achieve the combination between the two through certain process means (such as infiltration process, sintering process, hot pressing process, deposition process, etc.); after forming, polish the surface of the electrode structure to meet the specified flatness and roughness requirements, thus completing the preparation of the electrode structure.

[0080] It should be noted that there are no restrictions on the layout method of the metal grid framework, the size of the metal grid framework, the type and formula of the filled high thermal conductivity material, and the combination process between the metal grid framework and the high thermal conductivity material.

[0081] Example 4: Electrode structure based on a metal mesh skeleton (i.e., connected between two adjacent conductive parts).

[0082] First, according to the formula , calculate the volume of all the conductive parts required in the electrode structure, and then, according to the layout requirements of the conductive parts (i.e., the current uniformity requirements), evenly arrange a metal mesh framework in the mold (i.e., the shape formed by all the conductive parts is a mesh), and the height of the metal mesh framework is sufficient to penetrate the upper and lower surfaces of the electrode structure; then fill the gaps of the metal mesh framework with a high thermal conductivity material (such as copper-diamond, aluminum-diamond composite materials, etc.), and realize the combination between the two through certain process means (such as infiltration process, sintering process, hot pressing process, deposition process, etc.); after forming, polish the surface of the electrode structure to meet the specified flatness and roughness requirements, thus completing the preparation of the electrode structure.

[0083] It should be noted that there are no restrictions on the layout method of the metal mesh framework, the size of the metal mesh framework, the type and formula of the filled high thermal conductivity material, and the bonding process between the metal mesh framework and the high thermal conductivity material.

[0084] Example 5: An electrode structure based on a hybrid structure metal framework (i.e., the shapes of at least some of the conductive parts are different).

[0085] First, according to the formula , calculate the volume of all the conductive parts required in the electrode structure, and then, according to the layout requirements of the conductive parts (i.e., the current uniformity requirements), evenly arrange a hybrid structure metal framework mixed with some or all of the structures in the above 4 examples in the mold, and the height of the hybrid structure metal framework is sufficient to penetrate the upper and lower surfaces of the electrode structure; then fill the gaps of the hybrid structure metal framework with a high thermal conductivity material (such as copper-diamond, aluminum-diamond composite materials, etc.), and realize the combination between the two through certain process means (such as infiltration process, sintering process, hot pressing process, deposition process, etc.); after forming, polish the surface of the electrode structure to meet the specified flatness and roughness requirements, thus completing the preparation of the electrode structure.

[0086] It should be noted that there are no restrictions on the layout method and quantity of the hybrid structure metal framework, the geometric shape and size of the hybrid structure metal framework, the type and formula of the filled high thermal conductivity material, and the bonding process between the hybrid structure metal framework and the filler.

[0087] Specifically, among these 5 examples, the electrode structures of Example 1 and Example 2 are recommended because the processing technologies of these two electrode structures are simple, the processing accuracy is higher, and the surface flatness is easy to control, which can reduce the contact thermal resistance and contact resistance between the electrode structure and the device.

[0088] The embodiment of the present application also provides a chip, including: a chip body; at least one of any of the above electrode structures, and one of the above electrode structures is located on one side of the above chip body.

[0089] In the above embodiments, the chip includes a chip body and at least one electrode structure. One of the electrode structures is located on one side of the chip body. The electrode structure includes a body portion and a plurality of conductive portions. The body portion includes a first surface, a second surface, and a plurality of hollowed-out regions connecting the first surface and the second surface. Each conductive portion fills the hollowed-out region correspondingly. The material of the body portion includes an inorganic non-metallic solid material and a metal material, and the material of the conductive portion includes a metal material. The plurality of hollowed-out regions include a first hollowed-out region and a second hollowed-out region, and the distance between the first hollowed-out region and the second hollowed-out region is greater than half of the equivalent radius. Compared with the problems in existing power chips where the conductivity of the electrodes is poor and the current distribution inside the electrodes is uneven, thus affecting the chip performance, the electrode structure in the present application includes a body portion and a plurality of conductive portions. The body portion includes a plurality of hollowed-out regions, and the conductive portions fill the hollowed-out regions correspondingly, that is, metal conductive channels are introduced into the body portion to create low-resistance paths, allowing current to flow freely in these paths without being affected by the low conductivity of the body portion material. This is equivalent to implanting a high-conductivity network in a low-conductive material, ensuring good conductivity of the electrodes, and thus ensuring a low on-state voltage drop of the chip. In addition, there are a plurality of hollowed-out regions, and the distance between the first hollowed-out region and the second hollowed-out region among the plurality of hollowed-out regions is greater than half of the equivalent radius, ensuring a relatively uniform distribution of the conductive portions in the electrode structure, and thus ensuring a relatively uniform current distribution inside the electrodes, suppressing the problems of uneven local Joule heat effect and uneven thermal stress of the chip, and ensuring good reliability of the chip.

[0090] From the above description, it can be seen that the above embodiments of the present application achieve the following technical effects:

[0091] In the electrode structure of the present application, the electrode structure includes a body portion and a plurality of conductive portions. Among them, the body portion includes a first surface, a second surface, and a plurality of hollow regions connecting the first surface and the second surface. Each conductive portion correspondingly fills the hollow region. The material of the body portion includes an inorganic non-metallic solid material and a metal material, and the material of the conductive portion includes a metal material. The plurality of hollow regions include a first hollow region and a second hollow region, and the distance between the first hollow region and the second hollow region is greater than half of the equivalent radius. Compared with the problem in existing power devices that the conductivity of the electrode is poor and the current distribution inside the electrode is uneven, which affects the device performance, the electrode structure in the present application includes a body portion and a plurality of conductive portions. The body portion includes a plurality of hollow regions, and the conductive portions correspondingly fill the hollow regions, that is, a metal conductive channel is introduced into the body portion, creating a low-resistance path that allows current to flow freely in these paths without being affected by the low conductivity of the body portion material. This is equivalent to implanting a high-conductive network in a low-conductive material, ensuring good conductivity of the electrode, and thus ensuring a low on-state voltage drop of the device. In addition, there are a plurality of hollow regions, and the distance between the first hollow region and the second hollow region among the plurality of hollow regions is greater than half of the equivalent radius, ensuring a relatively uniform distribution of the conductive portions in the electrode structure, and thus ensuring a relatively uniform current distribution inside the electrode, suppressing the problems of uneven local Joule heat effect and uneven thermal stress of the device, and ensuring good reliability of the device.

[0092] The above are only the preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An electrode structure, characterized in that, The electrode structure includes: A body portion, including a first surface, a second surface, and a plurality of hollow regions penetrating the first surface and the second surface. The first surface and the second surface are opposite to each other. The plurality of hollow regions include a first hollow region and a second hollow region. The distance between the first hollow region and the second hollow region is greater than half of the equivalent radius, where the equivalent radius is the ratio of twice the area of the first surface to the perimeter of the first surface. The material of the body portion includes an inorganic non-metallic solid material and a metallic material. A plurality of conductive portions, each of which fills the hollow region correspondingly. The conductive portion includes a metallic material.

2. The electrode structure according to claim 1, wherein, The surface of the electrode structure has a plurality of regions, and the volumes of the regions are equal. Each region includes at least one end face of the conductive portion. The distance between the centroid of the region and the equivalent centroid of all the end faces of the conductive portions included in the region is not greater than one-third of the equivalent radius.

3. The electrode structure according to claim 2, characterized in that, Each region includes a first boundary line and a second boundary line. The first boundary line and the second boundary line intersect at the centroid of the surface of the electrode structure, and one end point of the first boundary line and one end point of the second boundary line are both the centroid of the surface of the electrode structure.

4. The electrode structure according to claim 2, wherein The volumes of the conductive portions corresponding to all the end faces of the conductive portions included in any two regions are equal.

5. The electrode structure according to any one of claims 1 to 4, characterized in that, The volume of all the conductive parts included in the electrode structure Satisfies: , represents the ratio of the equivalent conductivity required for the electrode structure under the same dimensions to the conductivity of standard annealed oxygen-free copper, represents the conductivity of the material of the conductive part, represents the conductivity of standard annealed oxygen-free copper, represents the total volume of the electrode structure.

6. The electrode structure according to any one of claims 1 to 4, characterized in that, The plurality of conductive portions include at least one of the following: columnar conductive portions and annular conductive portions.

7. The electrode structure according to claim 6, wherein Any two of the conductive parts are spaced apart and not connected, and the i-th conductive part satisfies: , where represents the minimum distance between the end face of the -th conductive part and the end face of the -th conductive part, represents the distance between the end face of the -th conductive part and the centroid of the surface of the electrode structure, represents the distance between the end face of the -th conductive part and the edge of the surface of the electrode structure, and R represents the equivalent radius.

8. The electrode structure according to claim 6, wherein, The number of the columnar conductive portions is 4 to 36.

9. The electrode structure according to claim 1, wherein Adjacent two of the conductive portions are connected, and the shape formed by at least part of the conductive portions is one of the following: grid-like and net-like.

10. A chip, characterized in that, Including: A chip body; At least one electrode structure according to any one of claims 1 to 9, and one electrode structure is located on one side of the chip body.

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