CN219626642U - Module with self-sealing structure - Google Patents

Abstract

The utility model provides a module with a self-sealing structure. Belongs to the technical field of power device manufacturing. The suspension crimping power device mainly solves the problem that the pressure drop stability of the device is affected by the fact that the potting material permeates into the surface of a chip in the existing suspension crimping power device. The main characteristics of the device are as follows: the device comprises a module bottom plate, an insulating heat conducting sheet, a metal electrode A, a lower cushion block, a lower molybdenum wafer, a crimping chip, an upper molybdenum wafer, an upper pressing block, a metal electrode K, a gate electrode lead assembly and a module plastic shell; the centers of the upper molybdenum wafer, the upper pressing block and the metal electrode K are provided with mounting holes; the gate lead assembly is clamped into the mounting hole and positioned, and the gate control electrode G is led out; the edge of the crimping chip is provided with a round boss for positioning; the metal electrode A, the lower cushion block, the lower molybdenum wafer, the crimping chip, the upper molybdenum wafer, the upper pressing block and the metal electrode K are in crimping contact in sequence. The utility model has the characteristics of reliability, practicability and self-sealing structure, and is mainly used for designing and packaging the power semiconductor module.

Description

Module with self-sealing structure

Technical Field

The utility model belongs to the technical field of power device manufacturing. Relates to the design and packaging of a suspension compression joint power device, in particular to a high-current power semiconductor module with greatly improved stability.

Background

At present, most of the suspension crimping power devices are composed of a bottom plate, electrodes, chips, an upper molybdenum wafer, a lower molybdenum wafer, an upper pressing block, a lower cushion block and a shell, positioning and integrated assembly are needed by a positioning ring during module assembly, the positioning ring is made of PPS/PBT or silica gel, the thickness of the suspension crimping chips is generally 0.2-2.5mm, the precision requirement on a positioning ring die is high, meanwhile, the positioning effect is needed, the size matching is tight, and the chips are extruded to a certain extent when the devices are subjected to thermal expansion and cold contraction during module packaging and actual use, so that the risk of chip breakage is increased; on the other hand, the PPS/PBT or the positioning ring made of silica gel cannot play a role in sealing, and the potting material such as gel, epoxy and the like of the inner cavity of the module infiltrates into the surface of the chip to influence the pressure drop stability of the device. With the rapid development of power semiconductor technology, the power device has raised higher requirements on reliability, and the stability of the device under extreme environments (such as H3TRB, high and low temperature abrupt changes) is a focus of some customers.

Disclosure of Invention

The present utility model aims to overcome the above-mentioned drawbacks by providing a reliable, practical and self-sealing module for power semiconductor module design and packaging.

The technical scheme of the utility model is as follows: the utility model provides a module with self sealss structure, includes module bottom plate, insulating conducting strip, metal electrode A, lower cushion, lower molybdenum disk, crimping chip, goes up molybdenum disk, goes up briquetting, metal electrode K, gate lead assembly and module plastic housing, characterized by: the center of the upper molybdenum wafer, the upper pressing block and the metal electrode K is provided with a mounting hole; the gate lead assembly is clamped into the mounting hole and positioned, and the gate control electrode G is led out; the edge of the crimping chip is provided with a round boss for positioning; the metal electrode A, the lower cushion block, the lower molybdenum wafer, the crimping chip, the upper molybdenum wafer, the upper pressing block and the metal electrode K are in crimping contact in sequence.

The circular boss comprises an upper circular boss on the upper side and a lower circular boss on the lower side.

The height of the upper circular boss is larger than the thickness of the upper molybdenum wafer in the technical solution of the utility model; the thickness of the lower circular boss is larger than that of the lower molybdenum wafer.

In the technical scheme of the utility model, the round boss is symmetrical in structure at two sides of the crimping chip and is connected into a whole.

The round boss is made of silica gel.

The crimping chip in the technical scheme of the utility model is a power semiconductor crimping chip, and a power semiconductor silicon wafer is arranged in the middle.

According to the technical scheme, the upper molybdenum wafer, the lower molybdenum wafer, the upper pressing block and the lower cushion block are in tight fit with the round boss.

The inner diameter of the upper molybdenum wafer and the lower molybdenum wafer is 0.05-0.2mm smaller than that of the circular boss, and the inner diameter of the upper pressing block and the lower cushion block is 0.05-0.2mm larger than that of the circular boss.

The thickness of the crimping chip in the technical solution of the utility model is 0.2-2.5mm.

In the technical scheme of the utility model, a sealed cavity is formed in a module plastic shell (11), and silica gel or epoxy resin is filled in the sealed cavity.

The utility model adopts a module with a self-sealing structure, which is composed of a module bottom plate, an insulating heat-conducting sheet, a metal electrode A, a lower cushion block, a lower molybdenum wafer, a crimping chip, an upper molybdenum wafer, an upper pressing block, a metal electrode K, a gate electrode assembly and a module plastic shell, wherein the centers of the upper molybdenum wafer, the upper pressing block and the metal electrode K are provided with mounting holes, the gate electrode lead assembly is clamped into the mounting holes and positioned to lead out a gate electrode control G, the edge of the crimping chip is provided with a circular boss for positioning, and the metal electrode A, the lower cushion block, the lower molybdenum wafer, the crimping chip, the upper molybdenum wafer, the upper pressing block and the metal electrode K are in crimping contact in sequence.

The utility model has the characteristics of reliability, practicability and self-sealing structure, and is mainly used for designing and packaging the power semiconductor module.

Drawings

Fig. 1 is a left side view of the construction of the module of the present utility model.

Fig. 2 is a left side view of a particular chip seal in a modular construction of the present utility model.

The reference numerals are: 1-a module base plate; 2-insulating heat conductive sheet; 3-metal electrode a; 4-a lower cushion block; 5-lower molybdenum wafer; 6-crimping the chip; 7-coating a molybdenum wafer; 8-pressing into blocks; 9-a metal electrode K; 10-gate lead assembly; 11-a module plastic housing; 12-a power semiconductor silicon wafer; 13-circular bosses; 14-chip sealing portion.

Detailed Description

Embodiments of the present utility model will be described more fully hereinafter with reference to the accompanying drawings in which embodiments of the utility model are shown.

As shown in fig. 1 and 2, an embodiment of a module with a self-sealing structure according to the present utility model is composed of a module base plate 1, an insulating and heat-conducting sheet 2, a metal electrode A3, a lower pad 4, a lower molybdenum wafer 5, a crimping chip 6, an upper molybdenum wafer 7, an upper pressing block 8, a metal electrode K9, a gate lead assembly 10 and a module plastic housing 11. Wherein, the module base plate 1, the insulating heat conducting fin 2, the metal electrode A3, the gate lead assembly 10 and the module plastic housing 11 are the same as those in the prior art, and the crimping chip 6 is a power semiconductor crimping chip.

The centers of the upper molybdenum wafer 7, the upper pressing block 8 and the metal electrode K9 are provided with mounting holes, the mounting holes are matched with the gate lead assembly 10, the gate lead assembly 10 is clamped into the mounting holes to be positioned, and the gate control electrode G is led out.

The crimping chip 6 is formed according to the design requirement, the middle is a power semiconductor silicon chip 12, the edge is provided with a round boss 13 for positioning, the thickness is 0.2-2.5mm, and the crimping chip and the silicon chip are integrally formed to play a role of a positioning ring. The circular boss 13 comprises an upper circular boss on the upper side and a lower circular boss on the lower side, the upper circular boss and the lower circular boss on the lower side are symmetrical in structure and are connected into a whole on the outer side, and the material is silica gel. The height of the upper circular boss is larger than the thickness of the upper molybdenum wafer 7, and the thickness of the lower circular boss is larger than the thickness of the lower molybdenum wafer 5. The round boss 13 is formed by high-temperature curing after silica gel is injected by a matched die, the inner diameters of the upper molybdenum disc 7 and the lower molybdenum disc 5 are slightly smaller than those of the round boss 13 by 0.05-0.2mm, the round boss 13 can be easily placed in the round boss, the inner diameters of the upper pressing block 8 and the lower cushion block 4 are slightly larger than those of the round boss 13 by 0.05-0.2mm, and the upper molybdenum disc 7, the lower molybdenum disc 5, the upper pressing block 8 and the lower cushion block 4 are in tight fit with the round boss 13.

A sealed cavity is formed in the module plastic shell 11, and a chip sealing part 14 between the metal electrode A3 and the metal electrode K9 in the sealed cavity is filled with silica gel or epoxy resin, so that water vapor or other harmful gases in the external environment are prevented from entering, and an external protection layer is formed.

The module is formed by directly mechanically pressing a module bottom plate 1, an insulating heat conducting sheet 2, a metal electrode A3, a lower cushion block 4, a lower molybdenum wafer 5, a crimping chip 6, an upper molybdenum wafer 7, an upper pressing block 8, a metal electrode K9 and a gate lead assembly 10, sleeving a module plastic shell 11, and encapsulating gel or epoxy resin. The metal electrode A3, the lower cushion block 4, the lower molybdenum wafer 5, the crimping chip 6, the upper molybdenum wafer 7, the upper pressing block 8 and the metal electrode K9 are in crimping contact in sequence.

In the implementation process, the method is carried out in a purifying environment, so that dust and impurities in the external environment are prevented from entering the surface of the chip, the flatness requirement of the contact layer of each accessory is less than 20 mu m, the roughness requirement is less than 0.5 mu m, and bad contact or damage to the chip is avoided.

The utility model has the advantages that: gel or epoxy resin filled in the cavity of the shell 11 can effectively prevent water vapor or other harmful gases in the external environment from entering, so as to form an external protection layer; the crimping chip 6 plays the positioning role through injection moulding's circular boss 13 on its mesa, and molybdenum disk 7, lower molybdenum disk 5, go up briquetting 8, lower cushion 4 are gone up in the location, avoid each part in the assembly process to be non-concentric, receive upper and lower shearing force and the chip is damaged after leading to the pressurized, injection moulding's circular boss 13 is integrative with power semiconductor silicon chip 12 simultaneously, can avoid the extrusion to the chip when expending with heat and shrinking, reduce the risk that the silicon chip breaks, and also can not influence the chip when having certain elasticity can with last briquetting 8, lower cushion 4 tight fit, play the sealed effect to the chip, avoided the inside embedment material gel of module or epoxy's infiltration, influence the stability of the pressure drop etc. electric properties of module.

The utility model can eliminate the influence of the sealing protection material (gel, epoxy resin, etc.) in the module on the electrical properties such as the pressure drop of the chip, has self-sealing effect, and has higher capability of resisting the influence of H3TRB and abrupt change of high and low temperatures.

The above description is only of the preferred embodiments of the present utility model and is not intended to limit the present utility model in any way. Therefore, any modification, equivalent substitution, equivalent variation and modification made to the above embodiments according to the technical substance of the present utility model still fall within the scope of the technical solution of the present utility model, all without departing from the content of the present utility model.

Claims (10)

1. The utility model provides a module with self sealss structure, includes module bottom plate (1), insulating conducting strip (2), metal electrode A (3), lower cushion (4), lower molybdenum disk (5), crimping chip (6), goes up molybdenum disk (7), goes up briquetting (8), metal electrode K (9), gate lead assembly (10) and module plastics shell (11), characterized by: the centers of the upper molybdenum wafer (7), the upper pressing block (8) and the metal electrode K (9) are provided with mounting holes; the gate electrode lead assembly (10) is clamped into the mounting hole and positioned, and the gate electrode control electrode G is led out; the edge of the crimping chip (6) is provided with a round boss (13) for positioning; the metal electrode A (3), the lower cushion block (4), the lower molybdenum wafer (5), the crimping chip (6), the upper molybdenum wafer (7), the upper pressing block (8) and the metal electrode K (9) are in crimping contact in sequence.

2. A module with self-sealing structure according to claim 1, characterized in that: the circular boss (13) comprises an upper circular boss on the upper side and a lower circular boss on the lower side.

3. A module with self-sealing structure according to claim 2, characterized in that: the height of the upper circular boss is larger than the thickness of the upper molybdenum wafer (7); the thickness of the lower circular boss is larger than that of the lower molybdenum wafer (5).

4. A module with self-sealing structure according to claim 1, 2 or 3, characterized in that: the round boss (13) is positioned on two sides of the crimping chip (6) and is symmetrical in structure and connected into a whole.

5. A module with self-sealing structure according to claim 4, characterized in that: the round boss (13) is made of silica gel.

6. A module with self-sealing structure according to any one of claims 1-3, 5, characterized in that: the crimping chip (6) is a power semiconductor crimping chip, and the middle is a power semiconductor silicon chip (12).

7. A module with self-sealing structure according to any one of claims 1-3, 5, characterized in that: the upper molybdenum wafer (7), the lower molybdenum wafer (5), the upper pressing block (8) and the lower cushion block (4) are tightly matched with the round boss (13).

8. A module with self-sealing structure according to claim 7, characterized in that: the inner diameters of the upper molybdenum wafer (7) and the lower molybdenum wafer (5) are 0.05-0.2mm smaller than the inner diameter of the circular boss (13), and the inner diameters of the upper pressing block (8) and the lower cushion block (4) are 0.05-0.2mm larger than the inner diameter of the circular boss (13).

9. A module with self-sealing structure according to any one of claims 1-3, 5, 8, characterized in that: the thickness of the crimping chip (6) is 0.2-2.5mm.

10. A module with self-sealing structure according to any one of claims 1-3, 5, 8, characterized in that: a sealed cavity is formed in the module plastic shell (11), and silica gel or epoxy resin is filled in the sealed cavity in a sealing mode.