Detachable power module sintering pressure head

Abstract

The utility model belongs to the technical field of semiconductor packaging, and particularly relates to a detachable power module sintering pressure head. The detachable power module sintering pressure head comprises a pressure base used for being connected with a pressure driving mechanism; the pressing blocks are detachably connected with the pressure base; wherein the pressing block is provided with a plurality of bosses used for being in contact with a chip. The part for providing pressure and the part for contacting the chip of the sintering pressure head are detachably connected, so that the application universality is greatly improved, and the cost is reduced. And for different chip layouts and DBC sizes, only the design of the detachable pressing block needs to be changed, and the pressure base does not need to be changed, so that the cost and the flexibility of a production line are reduced. The boss of the contact chip or the DTS copper sheet can be designed according to the layout of the chip, on one hand, the application is more flexible compared with an independent pressure head, on the other hand, the stress on the chip is more uniform compared with an integrated pressure head, and the sintering quality is better.

Description

Technical Field

[0001] This utility model belongs to the field of semiconductor packaging technology, specifically relating to a detachable power module sintering pressure head. Background Technology

[0002] Wide-bandgap semiconductor materials, primarily SiC and GaN, possess characteristics such as high breakdown electric field, high saturation electron velocity, high thermal conductivity, high electron density, high mobility, and the ability to withstand high power. These make them ideal for fabricating power modules for high-frequency, high-voltage, and high-temperature applications, and they contribute to improving the efficiency and power density of power electronic systems. The increasing power density and miniaturization of devices make timely heat dissipation crucial for ensuring the performance and reliability of power devices. As a key channel for interface heat dissipation, the high-temperature reliability and heat dissipation capacity of the interconnect layer in the power module packaging structure are particularly important.

[0003] Nano-silver sintering, as a low-temperature bonding technology, achieves dense bonding by diffusing micron-, nano-, or micro-nano-scale mixed silver atoms under specific temperature and pressure, achieving a sintering temperature similar to traditional solder. Its bonding layer, composed of silver or copper, possesses excellent electrical and thermal conductivity, meeting the requirements of low-temperature interconnection and high-temperature operation in third-generation semiconductor power module packaging. It has already seen widespread application in power device manufacturing. Similarly, DTS (Die Top System) technology is also maturely applied in power semiconductor module packaging.

[0004] Sintering nano-silver requires a sintering head, and existing sintering heads are divided into independent heads and integrated heads. Independent heads are customized for each chip based on its layout. Their advantage is that they can compensate for differences in substrate curvature and silver paste thickness, resulting in more uniform pressure on each chip and improved sintering quality. However, their disadvantages are limited flexibility and higher cost. Integrated heads can perform integrated operations on chips with different layouts. However, their disadvantage is that the pressure transmitted to each chip is not uniform enough, leading to significant differences in sintering quality between chips. This is especially true when sintering DTS copper sheets, where the small area and large number of DTS copper sheets make uneven pressure more likely to result in poorly sintered copper sheets. However, both independent and integrated heads have a single integrated part that contacts the chip or DTS copper sheet and provides pressure, making them suitable only for products with a single DBC size or chip layout. Changing the head requires replacing the entire head, limiting its application and increasing replacement costs. Utility Model Content

[0005] The purpose of this invention is to provide a detachable power module sintering pressure head to solve the technical problems of limited applicability and high replacement cost of existing sintering pressure heads.

[0006] This application provides a detachable power module sintering pressure head. The detachable power module sintering pressure head includes:

[0007] Pressure base, used to connect the pressure drive mechanism;

[0008] Several pressure blocks are detachably connected to the pressure base; among them

[0009] The pressure block is provided with several protrusions for contacting the chip.

[0010] In one embodiment of this application, the pressure block is provided with a plurality of recesses, and the recesses are provided with mounting holes.

[0011] In one embodiment of this application, the pressure block is square, and the recessed portion is located at the four corners of the pressure block.

[0012] In one embodiment of this application, the back of the pressure block is provided with a plurality of positioning holes;

[0013] The pressure base is provided with a positioning block that mates with the positioning hole.

[0014] In one embodiment of this application, the pressure base is provided with an air extraction groove.

[0015] In one embodiment of this application, the air extraction groove is located between adjacent pressure blocks.

[0016] In one embodiment of this application, the size of the boss is the same as the size of the corresponding chip.

[0017] In one embodiment of this application, the size of the boss is the same as the size of the corresponding silver-plated area on the DBC substrate.

[0018] The beneficial effects of this utility model are:

[0019] Unlike existing technologies, the detachable power module sintering head of this application includes: a pressure base for connecting a pressure driving mechanism; and several pressure blocks detachably connected to the pressure base; wherein the pressure blocks are provided with several protrusions for contacting the chip. By making the pressure-providing part and the chip-contacting part of the sintering head detachably connected, the application versatility is greatly improved, and costs are reduced. To cope with different chip layouts and DBC sizes, only the design of the detachable pressure blocks needs to be changed, without changing the pressure base, thus reducing costs and increasing production line flexibility. The protrusions contacting the chip or DTS copper sheet can be designed according to the chip layout, which is more flexible than independent pressure heads and provides more uniform force on the chip than integrated pressure heads, resulting in better sintering quality.

[0020] Other features and advantages of this invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objectives and other advantages of this invention are realized and obtained through the structures particularly pointed out in the description and the accompanying drawings.

[0021] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0022] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0023] Figure 1 This is a perspective view of a preferred embodiment of the detachable power module sintering pressure head of this utility model;

[0024] Figure 2 This is a front view of the pressing block according to a preferred embodiment of the present invention;

[0025] Figure 3 This is a schematic diagram of the back of the pressing block according to a preferred embodiment of the present invention;

[0026] Figure 4 This is a schematic diagram of the layout of a DBC substrate according to an embodiment of the present invention;

[0027] Figure 5 This is an exploded view of a preferred embodiment of the detachable power module sintering pressure head of this utility model.

[0028] In the picture:

[0029] Pressure base 1, pressure block 2, boss 21, recess 22, mounting hole 23, positioning hole 24, air extraction groove 12, DBC substrate 100, chip 101, silver plating area 102, silver paste 103. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0031] This application provides a detachable power module sintering pressure head, which will be described in detail below. It should be noted that the order of description of the following embodiments is not intended to limit the preferred order of the embodiments of this application. Furthermore, in the following embodiments, the descriptions of each embodiment have their own emphasis; parts not described in detail in a certain embodiment can be referred to in the relevant descriptions of other embodiments.

[0032] See Figure 4 The layout of a DBC substrate 100 includes several silver-plated areas 102 on its surface, silver paste 103 in the silver-plated areas 102, and a chip 101 on the silver paste 103.

[0033] See Figure 1 and Figure 2 In one embodiment, the detachable power module sintering head includes: a pressure base 1 for connecting a pressure driving mechanism; and a plurality of pressure blocks 2 detachably connected to the pressure base 1; wherein the pressure blocks 2 are provided with a plurality of protrusions 21 for contacting the chip 101.

[0034] In this embodiment, the pressure driving mechanism can be a hydraulic cylinder or other mechanism that provides pressure, which can drive the pressure base 1 to move, and can be implemented using existing technology. The pressure block 2 is detachably connected to the pressure base 1, and the pressure block 2 and its boss 21 can be designed according to specific needs. In different applications, only the pressure block 2 on the pressure base 1 needs to be replaced.

[0035] Optionally, the pressure block 2 can be detachably connected to the pressure base 1 via a fastener.

[0036] For details, see Figure 2 The pressure block 2 is provided with a plurality of recesses 22, and the recesses 22 are provided with mounting holes 23.

[0037] In this embodiment, the recess 22 can be used to accommodate the protruding end of the fastener, such as the nut portion of a screw. The mounting hole 23 allows the fastener to pass through to fix the pressure block 2 onto the pressure base 1. Optionally, the mounting hole 23 can be a screw hole or a through hole, and the pressure base 1 is also provided with a corresponding screw hole. The fastener can be a screw, which passes through the mounting hole 23 and is screwed into the screw hole on the pressure base 1.

[0038] Optionally, a number of protrusions 21 may be located in the central region of the pressing block 2, and recesses 22 may be located in the edge region of the pressing block 2.

[0039] Preferably, the pressing block 2 is square, and the recessed portion 22 is provided at the four corners of the pressing block 2.

[0040] Further, see Figure 3 and Figure 4The back of the pressure block 2 is provided with a plurality of positioning holes 24; the pressure base 1 is provided with a positioning block 11 that cooperates with the positioning holes 24.

[0041] In this embodiment, the pressure block 2 and the pressure base 1 can be pre-positioned by the cooperation of the positioning block 11 and the positioning hole 24, and then fixedly connected by the fastener.

[0042] In some applications, organic matter may volatilize during the silver paste sintering process. If this volatilization is not promptly removed, it can adhere to the substrate or chip, causing contamination and affecting bonding and copper sheet sintering. (See also...) Figure 1 In this embodiment, preferably, the pressure base 1 is provided with an air extraction groove 12.

[0043] Existing sintering pressure heads rely on external sintering chambers for venting, with the vents being far from the product, making it impossible to directly and effectively remove the volatile organic compounds from the silver paste. In this embodiment, the venting groove 12 is directly installed on the pressure base 1, allowing for close-range venting and improving the venting effect.

[0044] Preferably, the air extraction groove 12 is located between adjacent pressure blocks 2.

[0045] Optionally, the size of the protrusion 21 is the same as the size of the corresponding chip 101. One protrusion 21 can correspond to one chip 101.

[0046] Optionally, the size of the boss 21 is the same as the size of the corresponding silver-plated area 102 on the DBC substrate 100. One boss 21 may correspond to multiple chips 101 within one silver-plated area 102.

[0047] In summary, the detachable power module sintering pressure head of this utility model has the following advantages:

[0048] 1. The innovative design separates the pressure-providing part of the sintering head from the chip contact part, greatly expanding the applicability of applications and reducing costs.

[0049] 2. To accommodate different chip layouts and DBC sizes, only the design of the removable pressure block needs to be changed, without altering the pressure base, thus reducing costs and increasing production line flexibility.

[0050] 3. The detachable pressure block contacts the chip or DTS copper sheet with protrusions that can be designed according to the chip layout. On the one hand, it is more flexible in application than independent pressure heads. On the other hand, compared with integrated pressure heads, the chip force area is more uniform, which can compensate for the height difference between chips caused by DBC warpage and silver paste printing thickness differences, resulting in better sintering quality.

[0051] 4. The pressure base has venting grooves to extract the organic matter volatilized from the silver paste during sintering, preventing it from adhering to the DBC and chip surface, and improving bonding and sintering quality.

[0052] It should be noted that all the devices (parts whose specific structures are not specified) selected in this application are general standard parts or parts known to those skilled in the art, and their structures and principles can be known to those skilled in the art through technical manuals or conventional experimental methods.

[0053] In the description of the embodiments of this utility model, unless otherwise explicitly specified and limited, the terms "installation", "connection" and "linking" should be interpreted broadly, for example, they can be fixed connections, detachable connections, or integral connections.

[0054] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0055] Based on the above-described preferred embodiments of this utility model, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the technical concept of this utility model. The technical scope of this utility model is not limited to the contents of the specification.

Claims

1. A detachable power module sintering pressure head, characterized in that, include: Pressure base (1), used to connect the pressure drive mechanism; Several pressure blocks (2) are detachably connected to the pressure base (1); wherein The pressure block (2) is provided with a plurality of protrusions (21) for contacting the chip (101).

2. The detachable power module sintering pressure head according to claim 1, characterized in that, The pressure block (2) is provided with a plurality of recesses (22), and the recesses (22) are provided with mounting holes (23).

3. The detachable power module sintering pressure head according to claim 2, characterized in that, The pressure block (2) is square, and the recessed portion (22) is located at the four corners of the pressure block (2).

4. The detachable power module sintering pressure head according to claim 1, characterized in that, The back of the pressure block (2) is provided with several positioning holes (24); The pressure base (1) is provided with a positioning block (11) that mates with the positioning hole (24).

5. The detachable power module sintering pressure head according to claim 1, characterized in that, The pressure base (1) is provided with an air extraction groove (12).

6. The detachable power module sintering pressure head according to claim 5, characterized in that, The air extraction groove (12) is located between adjacent pressure blocks (2).

7. The detachable power module sintering pressure head according to claim 1, characterized in that, The dimensions of the boss (21) are the same as those of the corresponding chip (101).

8. The detachable power module sintering pressure head according to claim 1, characterized in that, The dimensions of the boss (21) are the same as the dimensions of the corresponding silver-plated area (102) on the DBC substrate (100).

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