CN220400563U - Fixing device - Google Patents

Abstract

The utility model provides a fixing device, which is used for fixing a substrate by matching with a bearing platform, and comprises a pressing piece, wherein the pressing piece comprises: a first portion for pressing against the substrate; a second portion extending from the first portion toward the load-bearing platform. According to the fixing device, the first part of the pressing piece is used for pressing the substrate, the second part extends towards the bearing platform, the path of water entering from the side face of the substrate is blocked, and the water entering risk of the substrate is reduced.

Description

Fixtures

Technical field

The embodiment of the present invention relates to a fixing device.

Background technique

FIG. 1 shows a schematic diagram of a prior art fixing device, FIG. 2 shows a schematic diagram of a prior art fixing device, in which more fixing rods 214 of the carrying platform 210 are shown than in FIG. 1 , and FIG. 3 shows 4 shows a cross-sectional view taken along line a-a of FIG. 3 . Nowadays, the substrate 200 is getting thinner and thinner. In the flip chip connecting the die 300 to the substrate 200 In the bonding (Flip Chip Bond, FCB) process, the die area 206 of the substrate 200 for bonding the die 300 has more metal material than other areas, so it is more susceptible to thermal deformation than other areas. Therefore, currently The reflow step after the flip-chip bonding process requires pressing down other areas of the substrate 200 around the die area 206 through the first cover jig 220 and cooperating with the downward pressure provided by the carrying platform 210 negative pressure to minimize warpage. However, as shown in Figure 3, the existing first jig 220 needs to open holes to expose the die area 206 of the substrate 200, and cannot directly press down. The die area 206, and the downward negative pressure provided by the carrying platform 210 is small, so the existing fixing device is still quite limited in its ability to control the warpage of the die area 206 and the process. In the flip-chip bonding process and reflow process, the die area 206 cannot be flat enough.

In one embodiment, the substrate 200 is an embedded trace substrate (ETS) with two layers of traces fixed using the existing first jig 220. FIG. 5 shows the substrate 200 corresponding to a tube. In the contour diagram of the core 300-sized part, the units of the X-axis and Y-axis are pixels, which can be converted into length according to the resolution. It can be seen that the substrate 200 has a "crying face" shape with a high center and low surroundings, and In Figure 5, the height of the highest point is 13.8 μm, and the height of the lowest point is -20.1 μm, resulting in a warpage amount of approximately 34 μm. When the temperature is higher, the warpage amount of the substrate 200 is between 30 μm and 40 μm.

Referring to Figures 1, 2 and 4, during processing, the substrate 200 is first placed on the carrying platform 210, and then the first jig 220 and the carrying platform 210 are used to clamp the substrate 200; a flip chip bonding process is performed to The die 300 is connected to the substrate 200; a reflow soldering process is performed; the first jig 220 is replaced with the second jig 222 as shown in Figures 6 and 7, and a flux cleaning process is performed, where Figure 6 is a top view , Figure 7 is a cross-sectional view taken along line b-b of Figure 6 , the opening of the second jig 222 exposes all the die 300 , in this step, due to the gap 700 between the second jig 222 and the bearing platform 210 , the lining There is a risk of water entering the side of the bottom 200; then the substrate 200 is unbound from the carrying platform 210 and the second jig 222; and finally the substrate 200 is unloaded.

Utility model content

In view of the problems existing in the related art, the purpose of this utility model is to provide a fixing device to reduce the risk of water intrusion into the substrate.

In order to achieve the above purpose, the present invention provides a fixing device for fixing a substrate in conjunction with a bearing platform, including a pressing member. The pressing member includes: a first part for pressing against the substrate; a second part starting from the first part. A portion extends toward the load-bearing platform.

In some embodiments, the second portion is used to contact the carrying platform.

In some embodiments, the pressing member is magnetically attracted to the carrying platform.

In some embodiments, the bearing platform has a bearing surface and a magnetic component embedded at the bearing surface, and the magnetic component fixes the second part through magnetic force.

In some embodiments, the first part and the second part together have an L-shape in a cross-sectional view taken along the pressing direction of the first part.

In some embodiments, the pressing member further includes a slot for exposing a plurality of pads of the substrate.

In some embodiments, the first and second portions surround the slot.

In some embodiments, the fixing device further includes: an adhesive layer, adapted to be attached to a side of the substrate facing the carrying platform.

In some embodiments, the edges of the adhesive layer are not aligned with the edges of the substrate.

In some embodiments, the fixing device further includes: a carrier plate, adapted to be attached to a side of the adhesive layer facing the carrying platform.

In some embodiments, the hardness of the carrier plate is greater than the hardness of the adhesive layer.

In some embodiments, a plurality of first through holes are formed in the carrier board, and the first through holes penetrate the carrier board along the thickness direction of the carrier board.

In some embodiments, a plurality of second through holes are formed in the adhesive layer, and the second through holes penetrate the adhesive layer along the thickness direction of the adhesive layer.

In some embodiments, the first through hole and the second through hole correspond one to one and are aligned with each other.

In some embodiments, a carrier plate is used to contact the carrier platform.

In some embodiments, the carrier plate is made of material that is transparent to X-rays.

In some embodiments, the material of the carrier is AlCSi.

In some embodiments, the pressing member further includes a plurality of third through holes, and the third through holes penetrate the second part along the pressing direction of the pressing member.

In some embodiments, the bearing platform has a bearing surface and a fixing rod protruding relative to the bearing surface, and the third through hole is used to receive the fixing rod.

In some embodiments, the third through hole and the fixing rod fit each other.

The beneficial technical effects of this utility model are:

The first part of the pressing member of the fixing device in the embodiment of the present application is used to press against the substrate, and the second part extends toward the bearing platform, blocking the path of water ingress from the side of the substrate and reducing water intrusion into the substrate. risk.

Description of the drawings

Figure 1 shows a simplified diagram of a prior art fixture.

Figure 2 shows a simplified diagram of a prior art fixture.

Figure 3 shows a top view of a prior art fixture.

FIG. 4 shows a cross-sectional view taken along line a-a of FIG. 3 .

Figure 5 shows an isometric view of a substrate secured using a prior art fixture.

6 and 7 illustrate a second jig of the prior art.

8 and 9 show a schematic structural diagram of a fixing device according to an embodiment of the present application.

Figure 10 shows a top view of a fixation device according to an embodiment of the present application.

FIG. 11A shows a cross-sectional view taken along line c-c of FIG. 10 .

FIG. 11B shows a cross-sectional view taken along line c-c of FIG. 10 of a different embodiment than FIG. 11A .

Figure 12 shows the machine table with ejector pins.

Figure 13 shows an isometric view of a substrate secured using the fixture shown in Figure 11A.

Figures 14, 15, 16, and 17 are respectively along the a'-a' line, the a-a line in Figure 3 of the prior art, and the c'-c' line in Figure 10 of the embodiment of the present application. Schematic diagram of the pads of the substrate, the pads of the die and the solder taken from line c-c.

FIG. 18 is a graph showing changes in the amount of warpage in the control group 1 and the control group 2 as the temperature changes.

FIG. 19 is a graph showing the change amplitude of the warpage amount of the plurality of cells in Control Groups 1 to 4.

Detailed ways

In order to better understand the spirit of the embodiments of the present application, they will be further described below in conjunction with some preferred embodiments of the present application.

Embodiments of the present application will be described in detail below. Throughout this specification, identical or similar components and components having the same or similar functions are designated by similar reference numerals. The embodiments described herein with respect to the accompanying drawings are illustrative and diagrammatic in nature and are intended to provide a basic understanding of the present application. The embodiments of the present application should not be construed as limitations of the present application.

As used herein, the terms "approximately," "substantially," "substantially," and "about" are used to describe and illustrate small variations. When used in connection with an event or situation, the term may refer to instances in which the event or situation occurs precisely as well as instances in which the event or situation occurs closely.

In this specification, unless otherwise specified or limited, relative terms such as: "central", "longitudinal", "lateral", "front", "rear", "right" "of", "left", "inside", "outside", "lower", "higher", "horizontal", "vertical", "above", "below" , "above", "below", "top", "bottom" and their derivatives (such as "horizontally", "downward", "upwardly", etc.) should be interpreted as quotations Orientations are described in the Discussion or illustrated in the accompanying drawings. These relative terms are only used for convenience of description and do not require the present application to be constructed or operated in a particular direction.

For ease of description, "first," "second," "third," etc. may be used herein to distinguish different components of a figure or a series of figures. "First", "second", "third", etc. are not intended to describe corresponding components.

Figures 8 and 9 show a schematic structural diagram of a fixing device according to an embodiment of the present application. Figure 9 shows more fixing rods 214 of the carrying platform 210 than Figure 8 . Figure 10 shows a top view of the fixing device. Figure 11A A cross-sectional view taken along line c-c in Figure 10 is shown. The embodiment of the present application provides a fixing device for fixing the substrate 200 in cooperation with the bearing platform 210. The fixing device includes a pressing member 10, and the pressing member 10 includes: One part 11 is used to press the substrate 200; the second part 12 extends from the first part 11 toward the carrying platform 210. The first part 11 of the pressing member 10 of the fixing device in the embodiment of the present application is used to press the substrate 200, and the second part 12 extends toward the carrying platform 210, blocking the path of water from the side of the substrate 200, reducing the The risk of water intrusion into the substrate 200 is eliminated.

In some embodiments, the second part 12 is used to contact the bearing platform 210, and the second part 12 abuts the bearing platform 210, so that the distance between the first part 11 and the bearing platform 210 is fixed, that is, the first part 11 The downward force provided to the substrate 200 is fixed and will not aggravate the warpage of the substrate 200 due to the unstable position of the first part 11 .

In some embodiments, the pressing member 10 is magnetically attracted to the bearing platform 210 , so the pressing member 10 cannot easily move relative to the bearing platform 210 . Referring to FIG. 11A , in some embodiments, the bearing platform 210 has a bearing surface 212 and a magnetic component 204 embedded in the bearing surface 212 . The magnetic component 204 fixes the second part 12 through magnetic force, and the second part 12 contacts the magnetic component 204 . In some embodiments, magnetic member 204 is a magnet.

In some embodiments, in a cross-sectional view taken along the pressing direction of the first part 11 , the first part 11 and the second part 12 together have an (inverted) L-shaped shape.

Referring to FIG. 11A , in some embodiments, the pressing member 10 further includes a slot 14 for exposing a plurality of pads 140 of the substrate 200 . In some embodiments, the first portion 11 and the second portion 12 surround the slot 14 .

In some embodiments, the fixing device further includes an adhesive layer 20 for being attached to the side of the substrate 200 facing the carrying platform 210 .

Referring to FIG. 11A , in some embodiments, the edges of the carrier plate 30 , the edges of the adhesive layer 20 , and the edges of the substrate 200 are aligned. In some embodiments, the edge of the carrier plate 30, the edge of the adhesive layer 20, and the edge of the substrate 200 are not aligned, for example, the edges of the carrier plate 30 and the adhesive layer 20 exceed the edge of the substrate 200 (see Figure 11B), or The edges of the carrier plate 30 and the adhesive layer 20 are both recessed relative to the edges of the substrate 200 . The edge of the carrier plate 30 exceeds the edge of the adhesive layer 20 and the edge of the substrate 200 . In some embodiments, the edge of the adhesive layer 20 is not aligned with the edge of the substrate 200 , for example, the edge of the adhesive layer 20 exceeds the edge of the substrate 200 (see FIG. 11B ), or is recessed relative to the edge of the substrate 200 .

In some embodiments, the fixing device further includes: a carrier plate 30 for being attached to the side of the adhesive layer 20 facing the carrying platform 210 . The embodiment of the present application uses the combination of the carrier plate 30 and the adhesive layer 20 to provide downward adhesive force for all areas of the substrate 200 in the horizontal direction, so that the substrate 200 is attached to the carrier plate 30 and the use of the substrate 200 is improved. The die area where the die 300 is bonded can also receive a downward force, effectively leveling the substrate 200 . Moreover, the embodiment of the present application does not require the carrying platform 210 to provide negative pressure to achieve flattening of the substrate 200 . In some embodiments, the upper surface of the tube core 300 is not higher than the upper surface of the pressing member 10 . For example, the thickness of the tube core 300 may be 100 μm to 750 μm, and the thickness of the first part 11 of the pressing member 10 may be 1 mm.

In some embodiments, the hardness of the carrier plate 30 is greater than the hardness of the adhesive layer 20 .

Referring to FIG. 11A , in some embodiments, a plurality of first through holes 41 are formed in the carrier plate 30 , and the first through holes 41 penetrate the carrier plate 30 along the thickness direction of the carrier plate 30 . In some embodiments, a plurality of second through holes 42 are formed in the adhesive layer 20 , and the second through holes 42 penetrate the adhesive layer 20 along the thickness direction of the adhesive layer 20 . In some embodiments, the first through hole 41 and the second through hole 42 correspond one to one and are aligned with each other.

In some embodiments, the carrier plate 30 is used to contact the carrier platform 210 . In some embodiments, the material of the carrier plate 30 can be penetrated by X-rays to facilitate inspection of joint quality and flatness, and is easy to process and has good adhesive layer adhesion, such as aluminum alloy. In some embodiments, the material of the carrier plate 30 is AlCSi or the like.

In some embodiments, the pressing member 10 further includes a plurality of third through holes 43 , and the third through holes 43 penetrate the second part 12 along the pressing direction of the pressing member 10 . In some embodiments, the bearing platform 210 has a bearing surface 212 and a fixing rod 214 protruding relative to the bearing surface 212 , and the third through hole 43 is used to receive the fixing rod 214 .

In some embodiments, the third through hole 43 and the fixing rod 214 may fit together as shown in FIG. 11A . In other embodiments, there may also be a gap 900 between the third through hole 43 and the fixing rod 214 as shown in FIG. 9 , because the third through hole 43 is opened on the second part 12 instead of the first part 11 , the gap 900 will not affect the waterproof effect of the pressing member 10 .

The embodiments of the present application can share the bearing platform 210 of the prior art, and also share some of the processing steps of the prior art. The difference is that the embodiments of the present application perform the flip-chip bonding process, the reflow soldering process, and the cleaning process. There is no need to replace the fixture as in the prior art, but the pressing member 10 can always be used, which simplifies the production process. The difference is that, referring to FIG. 12 , a machine with an ejector pin 1200 is used. The ejector pin 1200 passes through the first through hole 41 and the second through hole 42 to push open the substrate 200 . The substrate 200 and the adhesive layer 20 , the carrier board 30 is detached. The carrier plate 30 and the adhesive layer 20 can be used to support other substrates 200 after being cleaned and recycled.

FIG. 13 is a contour diagram of a portion corresponding to the size of one die 300 of the substrate 200 fixed using the fixing device shown in FIG. 11A. The units of the X-axis and the Y-axis are pixels, which can be converted into length according to the resolution. degree, it can be obtained that the amount of warpage of the substrate 200 fixed by the fixing device of the embodiment of the present application is small, and the central area of the substrate 200 (the die area used for bonding the die 300 is located in the central area) is particularly flat. . In some embodiments, units of substrate 200 (corresponding to portions the size of one die 300) warp by less than 10 μm.

Figures 14, 15, 16, and 17 are respectively along the a'-a' line, the a-a line in Figure 3 of the prior art, and the c'-c' line in Figure 10 of the embodiment of the present application. The schematic diagram of the pad 140 of the substrate 200, the pad 144 of the die, and the solder 142 taken along line c-c shows that the spacing between the pads 140 and 144 in the prior art is uncertain, and the difference is large. When the spacing is large (for example, the middle diagram in Figure 14), there may be air welding/cold welding. However, in the embodiment of the present application, the spacing between the pads 140 and 144 is constant, the difference is small, and the welding situation is stable.

The carrier plate 30 and the adhesive layer 20 of the embodiment of the present application can handle most warped substrates 200 , including substrates 200 using special materials, such as low CTE (eg, 10 ppm/℃) materials and the prior art. An ultra-low coefficient of thermal expansion (CTE) (for example, <5ppm/°C) material (higher rigidity) that cannot be processed by the jig 220. The control group 1 is a 2 to 6-layer substrate with a low thermal expansion coefficient, and its thickness is 100 to 800 μm. , using the fixing device of the prior art; the control group 2 is a 2 to 6-layer substrate with an ultra-low thermal expansion coefficient, and its thickness is 100 to 800 μm, using the fixing device of the prior art; the control group 3 is a low thermal expansion coefficient A substrate with 2 to 6 layers, with a thickness of 100 to 800 μm, uses the fixture of this application; the control group 4 is a substrate with 2 to 6 layers of ultra-low thermal expansion coefficient, with a thickness of 100 to 800 μm, using this application of fixtures. Figure 18 shows a graph 1800 of the change in warpage amount (in μm) of control group 1 and control group 2 as the temperature changes, in which the dotted line is the result of control group 1 and control group 2 using the embodiment of the present application. In the case of the fixation device, the solid line is the case of the control group 1 and the control group 2 using the fixation device of the embodiment of the prior art. FIG. 19 shows a graph 1900 of the change amplitude of the warpage amount (unit: μm) of a plurality of units in the control groups 1 to 4. The fixing device of the embodiment of the present application effectively reduces the amount of warpage of the substrate 200 .

The embodiment of the present application uses an adhesive layer (such as tape) 20 to attach the substrate 200 to the carrier board 30 and fix the die area of the substrate 200, thereby solving the problem of the existing technology's problem in the reflow soldering process in the die area. It is easy to warp due to lack of support. The embodiment of the present application uses an adhesive layer 20 to attach the substrate to a metal carrier plate 30 that is not easily deformed by heat. The adhesive layer 20 can provide good fixation, and the pressing member 10 does not need to be positioned under each die 300 The periphery of the die area is pressed, so only one slot 14 needs to be opened on the pressing member 10 to expose all the die areas at the same time. Therefore, it can be applied to various designs of substrates 200 and can be avoided during the cleaning step. Moisture and flux remain around the die area.

In the embodiment of the present application, the carrier board 30 is provided with a first through hole 41 , and the adhesive layer 20 is provided with a second through hole 42 , which allows the ejector pin 1200 to pass through and push away the substrate 200 , so that the substrate 200 is separated from the adhesive layer 20 Detach. Although the carrier plate 30 and the adhesive layer 20 are provided to support the substrate 200 so that the distance between the first part 11 and the bearing platform 210 becomes longer, the pressing member 10 also has a second part 12 extending toward the bearing platform 210, which is beneficial to pressing. The component 10 is fixed on the carrying platform 210 by magnetic attraction.

Compared with the prior art and the present application, when performing the flip chip process and the reflow soldering process, the prior art uses a mesh first fixture 220 , while the present application uses a pressure resistor with a complete slot 14 . component 10, so the metal material of the pressing component 10 is less than that of the first mesh fixture 220, which absorbs less heat in the high-temperature process (reflow soldering process) and makes it easier to control the temperature; the existing technology needs to carry The platform 210 provides negative pressure to level the substrate 200 together with the first fixture 220. However, this application does not require the carrying platform 210 to provide negative pressure; when the substrate 200 in the prior art is different, the first fixture 220 needs to follow. Replacement means changing the material or size of the first jig 220, which means changing the heat absorbed during the reflow soldering process. In the reflow soldering process, due to the change of the jig, the material, size, and reflow soldering parameters need to be readjusted. However, the embodiment of the present application uses a pressing member 10 with a complete slot 14. Even if the type of substrate 200 changes, there is no need to replace the pressing member 10. The above-mentioned problems of the prior art do not exist; Embodiments of the technology need to control the amount of warpage of the substrate 200, the coplanarity of the solder (solder ball) 142, the volume of the solder 142 to avoid contact between the solder 142 and the first fixture 220, etc. The embodiments of the present application only need to confirm The feeding quality of the carrier plate 30, for example, because the substrate 200 is supported by the carrier plate 30, it must be determined in advance that the carrier plate 30 itself is not warped, or that the carrier plate 30 is of the same height in the height direction (Z-axis direction); The amount of warpage of the substrate 200 using the fixture of the prior art depends on the design and material of the substrate 200, and is usually in a "crying face" shape. The substrate 200 using the embodiment of the fixture of the present application is mainly composed of The plate 30 and the adhesive layer 20 are controlled, and the warpage amount is less than 20 μm.

The above are only preferred embodiments of the present utility model and are not intended to limit the present utility model. For those skilled in the art, the present utility model may have various modifications and changes. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present utility model shall be included in the protection scope of the present utility model.

Claims (10)

1. A fixing device for fixing a substrate in cooperation with a load-bearing platform, comprising a pressing member, the pressing member comprising:

a first portion for pressing against the substrate;

a second portion extending from the first portion toward the load-bearing platform.

2. The fixture of claim 1, wherein the second portion is configured to contact the load-bearing platform.

3. The fixture of claim 1, wherein the load bearing platform has a load bearing surface and a magnetic member embedded at the load bearing surface, the magnetic member securing the second portion by magnetic force.

4. The fixation device of claim 1, wherein the first portion and the second portion together have an L-shape in a cross-sectional view taken along a pressing direction of the first portion.

5. The fixture of claim 1, wherein the press-on member further comprises a slot for exposing a plurality of pads of the substrate.

6. The fixation device of claim 5, wherein the first portion and the second portion surround the slot.

7. The fixture of claim 1, further comprising:

and the bonding layer is used for being attached to one side of the substrate facing the bearing platform.

8. The fixture of claim 7, wherein an edge of the adhesive layer is not aligned with an edge of the substrate.

9. The fixture of claim 7, further comprising:

and the carrier plate is used for being attached to one side of the bonding layer facing the bearing platform.

10. The fixture of claim 9, wherein the carrier plate has a hardness greater than the hardness of the adhesive layer.