IGCT device package structure

Abstract

The utility model relates to a kind of IGCT device packaging structure, it is related to chip packaging technical field, for solving the problem that the center gate region of chip exists and cathode molybdenum sheet contact when warping deformation occurs.It includes: cathode molybdenum sheet, recess is arranged on it;Chip, cathode face is placed on cathode molybdenum sheet;Wherein, comb structure is arranged on the cathode face of chip, comb structure is placed on cathode molybdenum sheet, cathode face has center gate region, center gate region is correspondingly arranged with recess, IGCT device packaging structure is structured as when center gate region is pressed deformation, the deformation part of center gate region is located in recess, and not with the contact of recess's groove bottom.The utility model of the..The internal space of recess can exist insulation gap between cathode molybdenum sheet by the utility model, prevent center gate region and cathode molybdenum sheet direct contact. Thus, the GK short-circuit risk caused by chip contact after being pressed deformation and cathode molybdenum sheet is avoided, and then the reliability of device is improved.

Description

Technical Field

[0001] This utility model relates to the field of chip packaging technology, and in particular to an IGCT device packaging structure. Background Technology

[0002] In existing edge-gate IGCT chips, the center position is far from the gate region. When the chip is turned off, the current is transferred from the comb to the ring gate region. Since the commutation path of the comb at the center position is long, the voltage is significantly lower than the gate voltage, resulting in a high risk of turn-off failure. Therefore, when designing the lateral structure of the edge-gate IGCT chip, the comb at the center position is eliminated.

[0003] However, this design results in a larger diameter of the annular area where the inner comb bars are distributed. Under no pressure, since the surface of the comb bars is higher than the surface of the gate, there is an insulating gap between the gate and the molybdenum sheet. However, when the chip is under pressure, the central gate region warps and deforms to a certain extent, posing a risk of contact with the cathode molybdenum sheet.

[0004] In other words, when the central gate region of the chip warps, there is a problem of contact with the cathode molybdenum sheet. Utility Model Content

[0005] This invention provides an IGCT device packaging structure to solve the problem of contact between the central gate region of the chip and the cathode molybdenum sheet when the central gate region of the chip warps.

[0006] This utility model provides an IGCT device packaging structure, which includes: A molybdenum cathode sheet with grooves provided thereon; The chip has its cathode surface placed on a molybdenum cathode sheet. The chip has a comb structure on its cathode surface, which is placed on the cathode molybdenum sheet. The cathode surface has a central gate region, which is correspondingly arranged with a groove. The IGCT device packaging structure is designed such that when the central gate region is deformed by pressure, the deformed part of the central gate region is located in the groove and does not contact the bottom of the groove.

[0007] In one embodiment, the groove is a circular groove, the central gate region is circular, and the central axis of the circular groove coincides with the center of the central gate region.

[0008] In one implementation, the diameter of the circular groove is smaller than the diameter of the central gate region.

[0009] In one embodiment, the groove opening is provided with a rounded chamfer, or the groove opening is provided with an anti-scratch layer, which is used to prevent the chamfer at the groove opening from scratching the chip.

[0010] In one embodiment, the IGCT device package structure further includes an elastic buffer. The elastic buffer is non-conductive and is disposed in a groove. One end of the elastic buffer is fixed to the bottom of the groove, and the other end of the elastic buffer is in contact with the central gate region. The IGCT device package structure is configured such that when the central gate region is deformed by pressure, the elastic buffer applies an anti-deformation force to the central gate region to reduce the amount of deformation of the central gate region.

[0011] In one embodiment, the elastic buffer includes a plurality of elastic buffer pillars spaced apart on the bottom of a groove. One end of each elastic buffer pillar is fixed to the bottom of the groove, and the other end contacts the central gate region. The IGCT device package structure is configured such that when the central gate region is deformed by pressure, the elastic buffer pillar applies an anti-deformation force to the central gate region to reduce the amount of deformation of the central gate region.

[0012] In one embodiment, multiple elastic buffer columns are divided into multiple groups, each group of elastic buffer columns is circularly distributed and spaced apart, and the multiple groups of elastic buffer columns are arranged radially at intervals along the circular groove.

[0013] In one embodiment, the center of the distribution circle of each set of elastic buffer pillars coincides with the central axis of the circular groove.

[0014] In one embodiment, the central axis of one of the multiple elastic buffer pillars coincides with the central axis of the circular groove. The other elastic buffer pillars in the multiple elastic buffer pillars are divided into multiple groups. Each group of elastic buffer pillars is circularly distributed and spaced apart. The multiple groups of elastic buffer pillars are arranged radially spaced along the circular groove.

[0015] In one embodiment, the resilient buffer column includes: The main body has an opening inside and is fixed to the bottom of the groove. The cover is placed at the opening of the oral cavity and has a through hole. The telescopic rod passes through the opening and the through hole. The telescopic rod is slidably connected to the opening. One end of the telescopic rod extending out of the through hole contacts the central gate pole region. Multiple tension springs are arranged around the circumference of the telescopic rod. One end of the tension spring is fixedly connected to the cover, and the other end of the tension spring is fixedly connected to the telescopic rod. A compression spring, one end of which is fixed to the bottom of the opening, and the other end of which is fixed to the telescopic rod; The IGCT device packaging structure is designed such that when the central gate region is compressed and deformed, the telescopic rod slides downward under pressure, the compression spring is in a compressed state, and multiple tension springs are in a stretched state.

[0016] Compared with existing technologies, the advantages of this invention lie in the fact that by providing a groove below the central gate region, the internal space of the groove ensures that when the central gate region of the chip is subjected to downward pressure, the downwardly protruding and deformed portion remains within the internal space of the groove. This ensures that even if the central gate region bulges downward under pressure, an insulating gap exists between it and the cathode molybdenum sheet thanks to the internal space of the groove, preventing direct contact between the central gate region and the cathode molybdenum sheet. This avoids the risk of a GK short circuit caused by the chip contacting the cathode molybdenum sheet after deformation under pressure, thereby improving the reliability of the device. Attached Figure Description The present invention will be described in more detail below based on embodiments and with reference to the accompanying drawings.

[0017] Figure 1 This is a schematic diagram of the structural composition of the IGCT device packaging structure in Embodiment 1 of this utility model; Figure 2 This is a schematic diagram of the structural composition of the IGCT device packaging structure in Embodiment 2 of this utility model; Figure 3 yes Figure 2 A schematic diagram of the layout of the medium-elastic buffer column; Figure 4 yes Figure 2 Schematic diagram of the structure of a medium-elastic buffer column; Figure 5 This is a schematic diagram of the structural composition of the IGCT device packaging structure in Embodiment 3 of this utility model; Figure 6 yes Figure 5 A schematic diagram of the layout of the medium-elastic buffer column; Figure 7 yes Figure 5 Schematic diagram of the structure of a medium-elastic buffer column; Figure 8 These are front views of the cathode surface of the IGCT device packaging structure in embodiments one to three of this utility model; Figure 9 This is a commutation circuit diagram of the inner ring comb bar in embodiments one to three of this utility model.

[0018] Figure label: 10. Cathode molybdenum sheet; 11. Groove; 111. Scratch-resistant layer; 20. Chip; 21. Cathode surface; 2111. Inner ring comb bar; 2112. Second ring comb bar; 212. Central gate electrode area; 213. Annular gate electrode area; 30. Elastic buffer; 31. Elastic buffer post; 311. Body; 3111. Opening mouth; 312. Cover; 313. Tension spring; 314. Compression spring; 315. Telescopic rod. Detailed Implementation

[0019] The present invention will be further described below with reference to the accompanying drawings.

[0020] Example 1 like Figure 1 As shown, this utility model provides an IGCT device packaging structure, which includes a molybdenum cathode sheet 10 and a chip 20. The molybdenum cathode sheet 10 has a groove 11 on it. The chip 20 has a cathode surface 21 placed on the molybdenum cathode sheet 10. A comb structure is provided on the cathode surface 21 of the chip 20, which is placed on the molybdenum cathode sheet 10. The cathode surface 21 has a central gate region 212, which is correspondingly positioned to the groove 11. The IGCT device packaging structure is configured such that when the central gate region 212 is deformed under pressure, the deformed portion of the central gate region 212 is located within the groove 11 and does not contact the bottom of the groove 11.

[0021] In the above configuration, by providing a groove 11 below the central gate region 212, the internal space of the groove 11 ensures that when the central gate region 212 of the chip 20 is pressed downwards, the downwardly protruding and deformed portion is located within the internal space of the groove 11. This ensures that even if the central gate region 212 bulges downwards under pressure, an insulating gap exists between it and the cathode molybdenum sheet 10 thanks to the internal space of the groove 11, preventing direct contact between the central gate region 212 and the cathode molybdenum sheet 10. This avoids the risk of a GK short circuit caused by the chip 20 contacting the cathode molybdenum sheet 10 after being deformed under pressure, thereby improving the reliability of the device.

[0022] Specifically, such as Figure 1 As shown, in one embodiment, the comb structure of chip 20 includes an inner comb bar 2111, a second comb bar 2112 wrapped around the outer periphery of the inner comb bar 2111, a third comb bar wrapped around the outer periphery of the second comb bar 2112, an (N-1)th comb bar, and an Nth comb bar wrapped around the outer periphery of the (N-1)th comb bar. Both the inner comb bar 2111 and the Nth comb bar are arranged in a ring shape.

[0023] It should be noted that the chip 20 in this embodiment is an edge-gate IGCT chip. In the prior art, the center position of the edge-gate IGCT chip is far from the gate region. When it is turned off, the current is transferred from the comb to the annular gate region. Since the commutation path of the comb at the center position is long, the voltage is significantly lower than the gate voltage, resulting in a high risk of turn-off failure. Therefore, in this embodiment, the comb at the center position is eliminated when designing the lateral structure of the edge-gate IGCT chip, resulting in a larger diameter of the annular region where the inner comb is distributed. Under no pressure, since the comb surface is higher than the gate surface, there is an insulating gap between the gate and the molybdenum sheet. However, when the chip is under pressure, the central gate region warps to a certain extent, posing a risk of contact with the cathode molybdenum sheet.

[0024] In this embodiment, a groove 11 is designed in the central area of ​​the contact surface between the cathode molybdenum sheet 10 and the chip. The groove depth is adjusted according to the different inner diameters of the inner ring comb 2111 distribution area of ​​the chip. That is, the larger the inner diameter, the groove depth is increased accordingly. While ensuring that the chip cathode electrode and the cathode molybdenum sheet 10 are in complete contact, the risk of GK short circuit caused by the chip 20 contacting the cathode molybdenum sheet 10 after being deformed by pressure is avoided, thereby improving the reliability of the device.

[0025] Specifically, such as Figure 1 As shown, in one embodiment, the groove 11 is a circular groove, and the central gate region 212 is circular, with the central axis of the circular groove coinciding with the center of the central gate region 212. This ensures that when the central gate region 212 is subjected to downward pressure, the portion protruding and deforming downwards is largely contained within the circular groove, preventing direct contact between the central gate region 212 and the cathode molybdenum sheet 10. This avoids the risk of a GK short circuit caused by the chip 20 contacting the cathode molybdenum sheet 10 after being deformed under pressure, thereby improving the reliability of the device.

[0026] Specifically, such as Figure 1 As shown, in one embodiment, the diameter of the circular groove is smaller than the diameter of the central gate region 212. This ensures that the cathode molybdenum sheet 10 completely covers the distribution area of ​​the comb structure.

[0027] Specifically, such as Figure 1 As shown, in one embodiment, the groove opening of the recess 11 is rounded. This effectively prevents the chip 20 from being scratched by the sharp corners of the groove opening, thus ensuring that the chip 20 can function properly after packaging.

[0028] Example 2 like Figure 2 As shown, this utility model provides an IGCT device packaging structure, which includes a molybdenum cathode sheet 10 and a chip 20. The molybdenum cathode sheet 10 has a groove 11 on it. The chip 20 has a cathode surface 21 placed on the molybdenum cathode sheet 10. A comb structure is provided on the cathode surface 21 of the chip 20, which is placed on the molybdenum cathode sheet 10. The cathode surface 21 has a central gate region 212, which is correspondingly positioned to the groove 11. The IGCT device packaging structure is configured such that when the central gate region 212 is deformed under pressure, the deformed portion of the central gate region 212 is located within the groove 11 and does not contact the bottom of the groove 11.

[0029] By providing a groove 11 below the central gate region 212, the internal space of the groove 11 ensures that when the central gate region 212 of the chip 20 is pressed downwards, the downwardly protruding and deformed portion is located within the internal space of the groove 11. This ensures that even if the central gate region 212 bulges downwards under pressure, an insulating gap exists between it and the cathode molybdenum sheet 10 thanks to the internal space of the groove 11, preventing direct contact between the central gate region 212 and the cathode molybdenum sheet 10. This avoids the risk of a GK short circuit caused by the chip 20 contacting the cathode molybdenum sheet 10 after being deformed under pressure, thereby improving the reliability of the device.

[0030] Specifically, such as Figure 2 As shown, in one embodiment, the comb structure of chip 20 includes an inner comb bar 2111, a second comb bar 2112 wrapped around the outer periphery of the inner comb bar 2111, a third comb bar wrapped around the outer periphery of the second comb bar 2112, an (N-1)th comb bar, and an Nth comb bar wrapped around the outer periphery of the (N-1)th comb bar. Both the inner comb bar 2111 and the Nth comb bar are arranged in a ring shape.

[0031] It should be noted that the chip 20 in this embodiment is an edge-gate IGCT chip. In the prior art, the center position of the edge-gate IGCT chip is far from the gate region. When it is turned off, the current is transferred from the comb to the annular gate region. Since the commutation path of the comb at the center position is long, the voltage is significantly lower than the gate voltage, resulting in a high risk of turn-off failure. Therefore, in this embodiment, the comb at the center position is eliminated when designing the lateral structure of the edge-gate IGCT chip, resulting in a larger diameter of the annular region where the inner comb is distributed. Under no pressure, since the comb surface is higher than the gate surface, there is an insulating gap between the gate and the molybdenum sheet. However, when the chip is under pressure, the central gate region warps to a certain extent, posing a risk of contact with the cathode molybdenum sheet.

[0032] In this embodiment, a groove 11 is designed in the central area of ​​the contact surface between the cathode molybdenum sheet 10 and the chip. The groove depth is adjusted according to the different inner diameters of the inner ring comb 2111 distribution area of ​​the chip. That is, the larger the inner diameter, the groove depth is increased accordingly. While ensuring that the chip cathode electrode and the cathode molybdenum sheet 10 are in complete contact, the risk of GK short circuit caused by the chip 20 contacting the cathode molybdenum sheet 10 after being deformed by pressure is avoided, thereby improving the reliability of the device.

[0033] Specifically, such as Figure 2As shown, in one embodiment, the groove 11 is a circular groove, and the central gate region 212 is circular, with the central axis of the circular groove coinciding with the center of the central gate region 212. This ensures that when the central gate region 212 is subjected to downward pressure, the portion protruding and deforming downwards is largely contained within the circular groove, preventing direct contact between the central gate region 212 and the cathode molybdenum sheet 10. This avoids the risk of a GK short circuit caused by the chip 20 contacting the cathode molybdenum sheet 10 after being deformed under pressure, thereby improving the reliability of the device.

[0034] Specifically, such as Figure 2 As shown, in one embodiment, the diameter of the circular groove is smaller than the diameter of the central gate region 212. This ensures that the cathode molybdenum sheet 10 completely covers the distribution area of ​​the comb structure.

[0035] Specifically, such as Figure 2 As shown, in one embodiment, a scratch-resistant layer 111 is provided at the groove opening of the groove 11. The scratch-resistant layer 111 is used to prevent the chamfer at the groove opening from scratching the chip 20.

[0036] Specifically, such as Figure 2 As shown, in one embodiment, the IGCT device package structure further includes an elastic buffer 30. The elastic buffer 30 is non-conductive and is disposed within a groove 11. One end of the elastic buffer 30 is fixed to the bottom of the groove 11, and the other end of the elastic buffer 30 contacts the central gate region 212. The IGCT device package structure is configured such that when the central gate region 212 is deformed under pressure, the elastic buffer 30 applies an anti-deformation force to the central gate region 212 to reduce the amount of deformation of the central gate region 212. This effectively prevents the central gate region 212 from directly contacting the cathode molybdenum sheet 10. This avoids the risk of a GK short circuit caused by the chip 20 contacting the cathode molybdenum sheet 10 after being deformed under pressure, thereby improving the reliability of the device.

[0037] It should be noted that in this embodiment, a groove 11 and an elastic buffer 30 are provided. The elastic buffer 30 is used to reduce the amount of deformation, and the groove 11 is used to accommodate the deformed part. This can effectively prevent the central gate electrode region 212 from directly contacting the cathode molybdenum sheet 10.

[0038] It should be noted that the elastic buffer 30 has a buffering function. When the elastic buffer 30 applies an anti-deformation force to the central gate region 212, the cathode molybdenum sheet 10 and the chip 20 are not in rigid contact with the elastic buffer 30. This prevents damage to the cathode molybdenum sheet 10 and the chip 20 caused by rigid contact, thus ensuring the stable and reliable operation of the elastic buffer 30. Specifically, as... Figure 3As shown, in one embodiment, the elastic buffer 30 includes a plurality of elastic buffer pillars 31, which are spaced apart on the bottom of the groove. One end of each elastic buffer pillar 31 is fixed to the bottom of the groove 11, and the other end contacts the central gate region 212. The IGCT device packaging structure is configured such that when the central gate region 212 is deformed by pressure, the elastic buffer pillars 31 apply an anti-deformation force to the central gate region 212 to reduce the amount of deformation of the central gate region 212. In this way, the multiple elastic buffer pillars 31 can apply an anti-deformation force to the central gate region 212, so that the central gate region 212 is subjected to force at multiple points, thereby making the force uniform and preventing damage caused by excessive local force due to single-point force, thus ensuring that the chip 20 can work normally after packaging.

[0039] Specifically, such as Figure 3 As shown, in one embodiment, multiple elastic buffer pillars 31 are divided into multiple groups, each group of elastic buffer pillars 31 is circularly distributed and spaced apart, and the multiple groups of elastic buffer pillars 31 are arranged radially spaced along the circular groove. This layout allows the central gate region 212 to be subjected to force at multiple points, thereby making the force uniform and preventing damage caused by excessive local force due to single-point force, thus ensuring that the chip 20 can work normally after packaging.

[0040] Specifically, such as Figure 4 As shown, in one embodiment, the elastic buffer post 31 includes a body 311, a cover 312, and a telescopic rod 315. The body 311 has an opening 3111 inside and is fixed to the bottom of a groove. The cover 312 covers the opening of the opening 3111 and has a through hole. The telescopic rod 315 passes through the opening 3111 and the through hole, and is slidably connected to the opening 3111. One end of the telescopic rod 315 extending out of the through hole contacts the central gate region 212. Multiple tension springs 3... 13, which is arranged around the circumference of the telescopic rod 315, one end of the tension spring 313 is fixedly connected to the cover 312, and the other end of the tension spring 313 is fixedly connected to the telescopic rod 315; the compression spring 314, one end of which is fixed to the bottom end of the opening 3111, and the other end of the compression spring 314 is fixed to the telescopic rod 315; wherein, the IGCT device packaging structure is configured such that when the central gate region 212 is deformed by pressure, the telescopic rod 315 slides downward under pressure, the compression spring 314 is in a compressed state, and the multiple tension springs 313 are in a stretched state.

[0041] Of course, in alternative embodiments not shown in the accompanying drawings of this application, only a tension spring 313 or a compression spring 314 may be provided, depending on the actual situation.

[0042] It should be noted that the main body 311, the cover 312, and the telescopic rod 315 are all made of insulating material, while only the tension spring 313 and the compression spring 314 are made of metal. Thus, the elastic buffer post 31 is non-conductive and does not conduct electricity when in contact with the cathode molybdenum sheet 10 and the chip 20.

[0043] It should be noted that the bottom of the groove 11 is provided with multiple positioning holes, and the main body 311 is fixed in the corresponding positioning holes.

[0044] Example 3 like Figure 5 As shown, this utility model provides an IGCT device packaging structure, which includes a molybdenum cathode sheet 10 and a chip 20. The molybdenum cathode sheet 10 has a groove 11 on it. The chip 20 has a cathode surface 21 placed on the molybdenum cathode sheet 10. A comb structure is provided on the cathode surface 21 of the chip 20, which is placed on the molybdenum cathode sheet 10. The cathode surface 21 has a central gate region 212, which is correspondingly positioned to the groove 11. The IGCT device packaging structure is configured such that when the central gate region 212 is deformed under pressure, the deformed portion of the central gate region 212 is located within the groove 11 and does not contact the bottom of the groove 11.

[0045] By providing a groove 11 below the central gate region 212, the internal space of the groove 11 ensures that when the central gate region 212 of the chip 20 is pressed downwards, the downwardly protruding and deformed portion is located within the internal space of the groove 11. This ensures that even if the central gate region 212 bulges downwards under pressure, an insulating gap exists between it and the cathode molybdenum sheet 10 thanks to the internal space of the groove 11, preventing direct contact between the central gate region 212 and the cathode molybdenum sheet 10. This avoids the risk of a GK short circuit caused by the chip 20 contacting the cathode molybdenum sheet 10 after being deformed under pressure, thereby improving the reliability of the device.

[0046] Specifically, such as Figure 5 As shown, in one embodiment, the comb structure of chip 20 includes an inner comb bar 2111, a second comb bar 2112 wrapped around the outer periphery of the inner comb bar 2111, a third comb bar wrapped around the outer periphery of the second comb bar 2112, an (N-1)th comb bar, and an Nth comb bar wrapped around the outer periphery of the (N-1)th comb bar. Both the inner comb bar 2111 and the Nth comb bar are arranged in a ring shape.

[0047] It should be noted that the chip 20 in this embodiment is an edge-gate IGCT chip. In the prior art, the center position of the edge-gate IGCT chip is far from the gate region. When it is turned off, the current is transferred from the comb to the annular gate region. Since the commutation path of the comb at the center position is long, the voltage is significantly lower than the gate voltage, resulting in a high risk of turn-off failure. Therefore, in this embodiment, the comb at the center position is eliminated when designing the lateral structure of the edge-gate IGCT chip, resulting in a larger diameter of the annular region where the inner comb is distributed. Under no pressure, since the comb surface is higher than the gate surface, there is an insulating gap between the gate and the molybdenum sheet. However, when the chip is under pressure, the central gate region warps to a certain extent, posing a risk of contact with the cathode molybdenum sheet.

[0048] In this embodiment, a groove 11 is designed in the central area of ​​the contact surface between the cathode molybdenum sheet 10 and the chip. The groove depth is adjusted according to the different inner diameters of the inner ring comb 2111 distribution area of ​​the chip. That is, the larger the inner diameter, the groove depth is increased accordingly. While ensuring that the chip cathode electrode and the cathode molybdenum sheet 10 are in complete contact, the risk of GK short circuit caused by the chip 20 contacting the cathode molybdenum sheet 10 after being deformed by pressure is avoided, thereby improving the reliability of the device.

[0049] Specifically, such as Figure 5 As shown, in one embodiment, the groove 11 is a circular groove, and the central gate region 212 is circular, with the central axis of the circular groove coinciding with the center of the central gate region 212. This ensures that when the central gate region 212 is subjected to downward pressure, the portion protruding and deforming downwards is largely contained within the circular groove, preventing direct contact between the central gate region 212 and the cathode molybdenum sheet 10. This avoids the risk of a GK short circuit caused by the chip 20 contacting the cathode molybdenum sheet 10 after being deformed under pressure, thereby improving the reliability of the device.

[0050] Specifically, such as Figure 5 As shown, in one embodiment, the diameter of the circular groove is smaller than the diameter of the central gate region 212. This ensures that the cathode molybdenum sheet 10 completely covers the distribution area of ​​the comb structure.

[0051] It should be noted that if the cathode molybdenum sheet 10 does not completely cover the distribution area of ​​the comb structure, the actual usable area of ​​the cathode will be reduced, thus decreasing the current carrying capacity and turn-off capability.

[0052] Specifically, such as Figure 5 As shown, in one embodiment, a scratch-resistant layer 111 is provided at the groove opening of the groove 11. The scratch-resistant layer 111 is used to prevent the chamfer at the groove opening from scratching the chip 20.

[0053] Specifically, such as Figure 5As shown, in one embodiment, the IGCT device package structure further includes an elastic buffer 30. The elastic buffer 30 is non-conductive and is disposed within a groove 11. One end of the elastic buffer 30 is fixed to the bottom of the groove 11, and the other end of the elastic buffer 30 contacts the central gate region 212. The IGCT device package structure is configured such that when the central gate region 212 is deformed under pressure, the elastic buffer 30 applies an anti-deformation force to the central gate region 212 to reduce the amount of deformation of the central gate region 212. This effectively prevents the central gate region 212 from directly contacting the cathode molybdenum sheet 10. This avoids the risk of a GK short circuit caused by the chip 20 contacting the cathode molybdenum sheet 10 after being deformed under pressure, thereby improving the reliability of the device.

[0054] It should be noted that in this embodiment, a groove 11 and an elastic buffer 30 are provided. The elastic buffer 30 is used to reduce the amount of deformation, and the groove 11 is used to accommodate the deformed part. This can effectively prevent the central gate electrode region 212 from directly contacting the cathode molybdenum sheet 10.

[0055] It should be noted that the elastic buffer 30 has a buffering function. When the elastic buffer 30 applies an anti-deformation force to the central gate region 212, the cathode molybdenum sheet 10 and the chip 20 are not in rigid contact with the elastic buffer 30. This can prevent damage to the cathode molybdenum sheet 10 and the chip 20 caused by rigid contact between the elastic buffer 30 and the cathode molybdenum sheet 10 and the chip 20, thereby ensuring that the elastic buffer 30 can work stably and reliably.

[0056] Specifically, such as Figure 3 As shown, in one embodiment, the elastic buffer 30 includes a plurality of elastic buffer pillars 31, which are spaced apart on the bottom of the groove. One end of each elastic buffer pillar 31 is fixed to the bottom of the groove 11, and the other end contacts the central gate region 212. The IGCT device packaging structure is configured such that when the central gate region 212 is deformed by pressure, the elastic buffer pillars 31 apply an anti-deformation force to the central gate region 212 to reduce the amount of deformation of the central gate region 212. In this way, the multiple elastic buffer pillars 31 can apply an anti-deformation force to the central gate region 212, so that the central gate region 212 is subjected to force at multiple points, thereby making the force uniform and preventing damage caused by excessive local force due to single-point force, thus ensuring that the chip 20 can work normally after packaging.

[0057] Specifically, such as Figure 6 As shown, in one embodiment, the central axis of one of the multiple elastic buffer pillars 31 coincides with the central axis of the circular groove. The other elastic buffer pillars in the multiple elastic buffer pillars 31 are divided into multiple groups. Each group of elastic buffer pillars is circularly distributed and spaced apart. The multiple groups of elastic buffer pillars are arranged radially spaced along the circular groove.

[0058] Specifically, such as Figure 7 As shown, in one embodiment, the elastic buffer post 31 includes a body 311, a cover 312, and a telescopic rod 315. The body 311 has an opening 3111 inside and is fixed to the bottom of a groove. The cover 312 covers the opening of the opening 3111 and has a through hole. The telescopic rod 315 passes through the opening 3111 and the through hole, and is slidably connected to the opening 3111. One end of the telescopic rod 315 extending out of the through hole contacts the central gate region 212. A tension spring 313 is also included. The telescopic rod 315 extends out of the through hole at one end, and the tension spring 313 is fixedly connected to the cover 312 at one end and to the telescopic rod 315 at the other end. The compression spring 314 is fixed at one end to the bottom of the opening 3111 at one end and to the telescopic rod 315 at the other end. The IGCT device packaging structure is configured such that when the central gate region 212 is deformed by pressure, the telescopic rod 315 slides downward under pressure, the compression spring 314 is in a compressed state, and the tension spring 313 is in a stretched state. Of course, in alternative embodiments not shown in the accompanying drawings of this application, only a tension spring 313 or a compression spring 314 may be provided, depending on the actual situation.

[0059] It should be noted that the main body 311, the cover 312, and the telescopic rod 315 are all made of insulating material, while only the tension spring 313 and the compression spring 314 are made of metal. Thus, the elastic buffer post 31 is non-conductive and does not conduct electricity when in contact with the cathode molybdenum sheet 10 and the chip 20.

[0060] It should be noted that the bottom of the groove 11 is provided with multiple positioning holes, and the main body 311 is fixed in the corresponding positioning holes.

[0061] It should be noted that, as Figure 8 As shown, the structures of chip 20 in embodiments one to three of this application are identical. A comb structure is provided on the cathode surface 21 of chip 20. The comb structure includes an inner comb bar 2111, a second comb bar 2112 wrapped around the outer periphery of the inner comb bar 2111, a third comb bar wrapped around the outer periphery of the second comb bar 2112, an (N-1)th comb bar, and an Nth comb bar wrapped around the outer periphery of the (N-1)th comb bar. The inner comb bar 2111 and the Nth comb bar are both arranged in a ring. Chip 20 has a ring-shaped gate region 213 and a central gate region 212. The central gate region 212 does not have an inner comb bar 2111.

[0062] It should be noted that, as Figure 9The diagram shows the commutation loop of the inner comb bar 2111 in the IGCT device package structure of this application. The arrows indicate the direction of current flow. In this application, when designing the lateral structure of the edge-gate IGCT chip, the comb bar at the center position is eliminated; that is, the inner comb bar 2111 is not set in the central gate region 212. This shortens the commutation path length of the comb bar at the center position, thereby reducing the risk of turn-off failure.

[0063] Although the present invention has been described with reference to preferred embodiments, various modifications can be made thereto and components can be replaced with equivalents without departing from the scope of the invention. In particular, the technical features mentioned in the various embodiments can be combined in any manner, provided there is no structural conflict. The present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. An IGCT device packaging structure, characterized in that, It includes: A molybdenum cathode sheet with grooves provided thereon; as well as The chip has its cathode surface placed on the cathode molybdenum sheet; The chip has a comb structure on its cathode surface, which is placed on the cathode molybdenum sheet. The cathode surface has a central gate region, which is correspondingly arranged with the groove. The IGCT device packaging structure is configured such that when the central gate region is deformed by pressure, the deformed part of the central gate region is located in the groove and does not contact the bottom of the groove.

2. The IGCT device packaging structure according to claim 1, characterized in that, The groove is a circular groove, the central gate region is circular, and the central axis of the circular groove coincides with the center of the central gate region.

3. The IGCT device packaging structure according to claim 2, characterized in that, The diameter of the circular groove is smaller than the diameter of the central gate region.

4. The IGCT device packaging structure according to claim 2, characterized in that, The groove opening is provided with a rounded chamfer, or the groove opening is provided with an anti-scratch layer, the anti-scratch layer being used to prevent the chamfer at the groove opening from scratching the chip.

5. The IGCT device packaging structure according to any one of claims 2 to 4, characterized in that, The IGCT device packaging structure also includes an elastic buffer, which is non-conductive and disposed in the groove. One end of the elastic buffer is fixed to the bottom of the groove, and the other end of the elastic buffer is in contact with the central gate region. The IGCT device packaging structure is configured such that when the central gate region is deformed by pressure, the elastic buffer applies an anti-deformation force to the central gate region to reduce the amount of deformation of the central gate region.

6. The IGCT device packaging structure according to claim 5, characterized in that, The elastic buffer includes multiple elastic buffer pillars, which are spaced apart on the bottom of the groove. One end of each elastic buffer pillar is fixed to the bottom of the groove, and the other end contacts the central gate region. The IGCT device packaging structure is configured such that when the central gate region is deformed by pressure, the elastic buffer pillar applies an anti-deformation force to the central gate region to reduce the amount of deformation of the central gate region.

7. The IGCT device packaging structure according to claim 6, characterized in that, The multiple elastic buffer pillars are divided into multiple groups, and each group of elastic buffer pillars is arranged in a circular pattern and spaced apart. The multiple groups of elastic buffer pillars are arranged at radial intervals along the circular groove.

8. The IGCT device packaging structure according to claim 7, characterized in that, The center of the distribution circle of each set of elastic buffer columns coincides with the central axis of the circular groove.

9. The IGCT device packaging structure according to claim 6, characterized in that, The central axis of one of the multiple elastic buffer pillars coincides with the central axis of the circular groove. The other elastic buffer pillars in the multiple elastic buffer pillars are divided into multiple groups. Each group of elastic buffer pillars is circularly distributed and spaced apart. The multiple groups of elastic buffer pillars are arranged radially spaced along the circular groove.

10. The IGCT device packaging structure according to claim 6, characterized in that, The elastic buffer column includes: The body has an opening inside, and the body is fixed to the bottom of the groove; and A cover body, which covers the opening of the oral cavity, the cover body being provided with a through hole; and A telescopic rod is inserted into the opening and the through hole, the telescopic rod is slidably connected to the opening, and one end of the telescopic rod extending out of the through hole contacts the central gate region; Multiple tension springs are arranged circumferentially around the telescopic rod, one end of each tension spring is fixedly connected to the cover, and the other end of each tension spring is fixedly connected to the telescopic rod; and A compression spring, one end of which is fixed to the bottom end of the opening, and the other end of which is fixed to the telescopic rod; The IGCT device packaging structure is configured such that when the central gate region is deformed by pressure, the telescopic rod slides downward under pressure, the compression spring is in a compressed state, and the multiple tension springs are in a stretched state.

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