CN211788998U - Suspension crimping power semiconductor module - Google Patents

Abstract

The utility model discloses a name is suspension crimping power semiconductor module. Belongs to the technical field of high-voltage power semiconductor devices. The method mainly solves the problems of welding stress and welding cavities existing in the existing chip and electrode plate which are welded by the solder at high temperature. It is mainly characterized in that: the module comprises a module bottom plate, an insulating heat-conducting strip, a metal A, K electrode, an upper molybdenum wafer, a lower molybdenum wafer, a power semiconductor chip, a gate pole assembly and a module plastic shell; the center of the upper molybdenum wafer is provided with a mounting hole; the gate pole lead wire component is clamped in the mounting hole for positioning; the metal A electrode, the lower molybdenum wafer, the power semiconductor chip, the upper molybdenum wafer, the gate lead assembly and the metal K electrode are in compression contact in sequence. The utility model has the characteristics of can eliminate the deformation and the stress that chip high temperature welding produced, can satisfy the high voltage that the customer provided to the module product, heavy current requirement, the high-voltage semiconductor device in fields such as mainly used high pressure soft start power, high-pressure static reactive power compensation power, high-pressure pulse power supply, high-voltage direct current transmission.

Description

Suspension crimping power semiconductor module

Technical Field

The utility model belongs to the technical field of high-voltage power semiconductor device. To a floating compression joint power semiconductor module. In particular to a high-current power semiconductor module with greatly improved performance. The method is mainly applied to the fields of UPS power supplies, high-voltage soft start power supplies, high-voltage static reactive compensation power supplies, high-voltage direct-current power transmission and the like.

Background

The internal structure of the traditional power semiconductor module chip is as follows: the semiconductor chip and rare metal molybdenum are welded by solder at high temperature, the chip used by the power semiconductor module is bent and deformed due to welding stress between the monocrystalline silicon wafer and the metal molybdenum, meanwhile, due to the relation of welding solder, a cavity exists in the welding of the monocrystalline silicon wafer and the metal molybdenum, the performance of the power semiconductor module, especially the performance of high-voltage and high-current products, is seriously influenced due to the reasons, and the durability and reliability of the power semiconductor module cannot meet new requirements due to physical deformation caused by high-temperature welding, so that a new semiconductor device structure and a new process technology are required to be adopted.

Disclosure of Invention

The utility model discloses to the aforesaid is not enough, provides a brand-new chip inner structure's suspension crimping power semiconductor module, can eliminate the deformation and the stress that preceding chip high temperature welding produced, can satisfy the requirement of high voltage, the heavy current that the customer provided to the module product.

The technical solution of the utility model is that: the utility model provides a suspension crimping power semiconductor module, includes module bottom plate, insulating conducting strip, metal A electrode, power semiconductor chip, gate pole subassembly, metal K electrode and module plastic casing, its characterized in that: the lower molybdenum wafer and the upper molybdenum wafer are also included; the center of the upper molybdenum wafer is provided with a mounting hole; the gate pole assembly is clamped in the mounting hole for positioning, and a gate pole control pole is led out; the metal A electrode, the lower molybdenum wafer, the power semiconductor chip, the upper molybdenum wafer, the gate pole component and the metal K electrode are in compression contact (ohmic contact) in sequence.

The technical solution of the utility model in the module plastic casing in form seal chamber, thereby it has gel or epoxy to be filled with in this seal chamber and has both guaranteed that each part contacts well each other, prevents again that chip oxidation or high pressure from striking sparks.

The technical solution of the utility model is that the two negative angle mesas on the two sides of the edge of the power semiconductor chip are provided with an annular right-angle cylindrical insulation protection silica gel ring, and the mesa on the two sides is provided with 2-4 layers of high-purity and high-insulativity polyimide passivation layers.

The technical solution of the utility model wherein the outer surface of silica gel ring be equipped with the recess, increase creepage distance.

The technical solution of the utility model the molybdenum disk and the upper and lower surface of last molybdenum disk, the inside and outside surface of metal A electrode and metal K electrode be the abrasive surface, face plane degree and depth of parallelism are less than 10 microns.

The technical solution of the utility model is that the surface of the upper molybdenum disk and the lower molybdenum disk is coated with a ruthenium passivation layer to prevent the thermal oxidation of the upper molybdenum disk and the lower molybdenum disk.

The technical solution of the utility model is that the cathode and anode surfaces of the power semiconductor chip are coated with metal conductive layers with the thickness of 10-100 microns.

The utility model discloses a technical solution in power semiconductor chip and last molybdenum disk and lower molybdenum disk between for the contact of suspension crimping.

The technical solution of the utility model is that the insulation protection silica gel ring on the table top with two negative angles on the edge two sides of the power semiconductor chip is matched with the upper molybdenum wafer and the lower molybdenum wafer in a positioning way respectively.

The technical solution of the utility model is that the table-board molding angle of the double negative angles of the two sides of the edge of the power semiconductor chip is between 0.5 degrees and 35 degrees.

The utility model discloses owing to adopt by metal A electrode, lower molybdenum disk, power semiconductor chip, go up the semiconductor device that the molybdenum disk, gate pole subassembly, metal K electrode and module plastic casing equipment formed, therefore power semiconductor chip and the direct crimping of upper and lower molybdenum disk no longer need the high temperature welding of traditional handicraft, just so eliminated the former chip high temperature welding and the deformation and the stress that produce, and then guaranteed the stability and the reliability of device characteristic.

The utility model discloses because two PN junction edges at power semiconductor chip adopt the mesa molding to adopt two negative angle mesa molding technology in two sides, reduced surface electric field intensity, be favorable to semiconductor chip breakdown voltage's improvement, its mesa molding angle theta size is: theta is more than or equal to 0.5 degree and less than or equal to 35 degrees; compared with the prior single-side table-board modeling, the method is simple and easy to implement in process, is beneficial to protecting the surface of the table-board, reduces the loss of the conductive areas of the cathode surface and the anode surface, and is beneficial to improving the through-current capacity of the chip.

The utility model adopts the strong electric field insulation protection technology on the table top shape protection at the edge of the power semiconductor chip, so that the power semiconductor chip can bear larger avalanche breakdown voltage and is not easy to break down; and the surface of the double-sided table board is protected, and 2-4 layers of high-purity high-insulation organic protective materials such as polyimide and the like are adopted for surface passivation, so that the stability and reliability of the device are improved. The power semiconductor chip double-sided table-board protection silica gel ring is in an annular right-angle cylindrical shape, so that the surface creepage distance is increased, and the power semiconductor chip can bear higher surface breakdown voltage; meanwhile, the molybdenum wafers are placed in the centers of the two sides of the power semiconductor chip, and the upper molybdenum wafer and the lower molybdenum wafer are positioned by utilizing the inner circle of the protective silica gel ring.

The utility model has the characteristics of can eliminate the deformation and the stress that the chip high temperature welding produced before, can satisfy the high-pressure semiconductor device requirement more than voltage 1000V and more than 4 inches of chip diameter. The utility model discloses the high-voltage semiconductor device in fields such as mainly used high-pressure soft start power, high-pressure static reactive power compensation power, high-voltage pulse power supply, high-voltage direct current transmission.

Drawings

Fig. 1 is a schematic structural view of a power semiconductor module of the present invention.

In the figure: 1. a module base plate; 2. an insulating heat-conducting sheet; 3. a metal A electrode; 4. a molybdenum wafer is put; 5. a power semiconductor chip; 6. loading a molybdenum wafer; 7. a gate assembly; 8. a metal K electrode; 9. a modular plastic housing.

Detailed Description

The present invention will be further described with reference to fig. 1.

As shown in fig. 1. The suspension compression joint power semiconductor module comprises a module bottom plate 1, an insulating heat conducting strip 2, a metal A electrode 3, a lower molybdenum wafer 4, a power semiconductor chip 5, an upper molybdenum wafer 6, a gate pole component 7, a metal K electrode 8 and a module plastic shell 9, and is formed by mechanical suspension compression joint packaging.

The module bottom plate 1, the insulating heat conducting strip 2, the metal A electrode 3, the gate pole component 7, the metal K electrode 8 and the module plastic shell 9 are the same as those in the conventional power semiconductor module. The differences are the connection mode between the power semiconductor chip 5 and the upper molybdenum disc 6 and the lower molybdenum disc 4, the installation position of the gate electrode assembly 7, and the appearance and surface treatment of the power semiconductor chip 5.

The table top with two negative angles on the two sides of the edge of the power semiconductor chip 5 is provided with an annular right-angled cylindrical insulation protection silica gel ring, the table top with two surfaces is provided with 2-4 layers of passivation layers made of organic protection materials such as high-purity high-insulation polyimide and the like, and the high-purity high-insulation refers to purity and insulation indexes meeting the conventional requirements. The outer surface of the silica gel ring is provided with a groove. Insulating protection silica gel rings on two negative angle table tops on two sides of the edge of the power semiconductor chip 5 are respectively matched with the upper molybdenum wafer 6 and the lower molybdenum wafer 4 in a positioning mode. The table-board modeling angle theta of the double negative angles of the two sides of the edge of the power semiconductor chip 5 is as follows: theta is more than or equal to 0.5 degree and less than or equal to 35 degrees. The cathode and anode surfaces of the power semiconductor chip 5 are coated with a metal conductive layer with the thickness of 10-100 microns.

The center of the molybdenum wafer 6 is provided with a mounting hole, and the gate pole component 7 is clamped in the mounting hole for positioning and is led out of the gate pole control pole. The upper and lower surfaces of the lower molybdenum wafer 4 and the upper molybdenum wafer 6, and the inner and outer surfaces of the metal A electrode 3 and the metal K electrode 8 are grinding surfaces, and the surface flatness and parallelism are less than 10 microns. The surfaces of the upper molybdenum wafer 6 and the lower molybdenum wafer 4 are coated with rare metals such as: a ruthenium passivation layer. The metal A electrode 3, the lower molybdenum wafer 4, the power semiconductor chip 5, the upper molybdenum wafer 6, the gate pole component 7 and the metal K electrode 8 are in compression contact in sequence. The power semiconductor chip 5 is in contact with the upper molybdenum wafer 6 and the lower molybdenum wafer 4 in a suspended compression joint mode. A sealed cavity is formed in the module plastic housing 9 and filled with gel or epoxy.

After the suspension compression joint process is adopted, the power semiconductor chip 5 is directly compressed and connected with the upper molybdenum wafer 4 and the lower molybdenum wafer 6 without high-temperature welding, so that the stress generated by sintering deformation of the chip in the prior art is eliminated, and the development of the chip to a larger diameter and a higher voltage is facilitated.

The assembly process is simple and convenient, the molybdenum wafer is directly placed one level upwards, the self-positioning mechanisms are arranged, the shell is directly installed on the bottom plate, and then the insulating heat conducting strip 2, the metal A electrode 3, the lower molybdenum wafer 4, the semiconductor chip 5, the gate pole assembly 7, the upper molybdenum wafer 6 and the metal K electrode 8 are placed. The power semiconductor chip 5 in the module is in suspension pressure contact with the upper molybdenum wafer 4 and the lower molybdenum wafer 6 under the action of external pressure, the upper surface and the lower surface of the upper molybdenum wafer 6 and the lower molybdenum wafer 4, and the inner surface and the outer surface of the metal A electrode 3 and the metal K electrode 8 are grinding surfaces, and the requirements on the surface flatness and the parallelism are less than 10 microns. The surfaces of the upper and lower molybdenum wafers 4 and 6 are coated with passivation materials to prevent the molybdenum wafers from being thermally oxidized, and the surfaces of the cathode and the anode of the semiconductor chip 5 are coated with thicker metal conducting layers. The interior of the device is sealed by gel, thereby ensuring good contact among all parts and preventing high-pressure ignition of the chip.

Claims (10)

1. The utility model provides a suspension crimping power semiconductor module, includes module bottom plate (1), insulating conducting strip (2), metal A electrode (3), power semiconductor chip (5), gate pole subassembly (7), metal K electrode (8) and module plastic casing (9), its characterized in that: the molybdenum-containing furnace also comprises a lower molybdenum wafer (4) and an upper molybdenum wafer (6); the center of the upper molybdenum wafer (6) is provided with a mounting hole; the gate pole component (7) is clamped in the mounting hole for positioning, and a gate pole control pole is led out; the metal A electrode (3), the lower molybdenum wafer (4), the power semiconductor chip (5), the upper molybdenum wafer (6), the gate pole component (7) and the metal K electrode (8) are in compression contact in sequence.

2. The floating crimped power semiconductor module according to claim 1, characterized in that: a sealed cavity is formed in the module plastic shell (9), and gel or epoxy resin is filled in the sealed cavity.

3. The floating crimping power semiconductor module according to claim 1 or 2, characterized in that: the table top of two negative angles of the edge of the power semiconductor chip (5) is provided with an annular right-angle cylindrical insulation protection silica gel ring, and the table top of the two surfaces is provided with 2-4 layers of polyimide passivation layers.

4. The floating crimped power semiconductor module according to claim 3, characterized in that: the outer layer surface of the silica gel ring is provided with a groove.

5. The floating crimping power semiconductor module according to claim 1 or 2, characterized in that: the upper and lower surfaces of the lower molybdenum wafer (4) and the upper molybdenum wafer (6), and the inner and outer surfaces of the metal A electrode (3) and the metal K electrode (8) are grinding surfaces, and the surface flatness and parallelism are less than 10 microns.

6. The floating crimping power semiconductor module according to claim 1 or 2, characterized in that: the surfaces of the upper molybdenum wafer (6) and the lower molybdenum wafer (4) are coated with ruthenium passivation layers.

7. The floating crimping power semiconductor module according to claim 1 or 2, characterized in that: and a metal conducting layer with the thickness of 10-100 microns is coated on the surface of the cathode and the anode of the power semiconductor chip (5).

8. The floating crimping power semiconductor module according to claim 1 or 2, characterized in that: the power semiconductor chip (5) is in contact with the upper molybdenum wafer (6) and the lower molybdenum wafer (4) in a suspended compression joint mode.

9. The floating crimping power semiconductor module according to claim 1 or 2, characterized in that: and the insulating protection silica gel rings on the double-negative-angle table top on the two sides of the edge of the power semiconductor chip (5) are respectively matched with the upper molybdenum wafer (6) and the lower molybdenum wafer (4) in a positioning manner.

10. The floating crimped power semiconductor module according to claim 4, characterized in that: the table-board modeling angle of the double negative angles of the two sides of the edge of the power semiconductor chip (5) is between 0.5 degrees and 35 degrees.

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