Soldering flux application device and soldering flux application method

Abstract

The application relates to a flux coating device and a flux coating method. The flux coating device comprises a base, a rotating structure on the base, the rotating structure comprising a first sleeve, a second sleeve and a rotating shaft, the second sleeve being nested in the first sleeve, the rotating shaft being nested in the second sleeve, the rotating shaft and the second sleeve having a containing groove containing flux therebetween, the side wall of the first sleeve having a first notch, the side wall of the second sleeve having a second notch, the rotating shaft being connected to the first sleeve, and the flux being capable of flowing out of the rotating structure after the first notch and the second notch are aligned. The application realizes control of the amount of flux, reduces waste of the flux and lowers the cost of chip welding.

Description

Technical Field

[0001] This invention relates to the field of integrated circuit manufacturing technology, and in particular to a flux coating apparatus and a flux coating method. Background Technology

[0002] Flip chip (FC) is a commonly used semiconductor packaging technology that mounts a chip onto a packaging substrate by flipping it over. During the flip chip process, a soldering head typically applies flux to the adhesive-coated area of ​​the chip before mounting it onto the packaging substrate. To improve the uniformity of flux distribution in the adhesive-coated area, the flux coating device needs to reciprocate horizontally during flux application. However, this reciprocating motion causes synchronous movement of the flux within the device, potentially resulting in flux covering non-adhesive-coated areas of the chip (i.e., outside the adhesive-coated area), leading to flux waste. Furthermore, the flux coating device only applies flux when it reaches the corresponding adhesive-coated area, resulting in low packaging efficiency. Additionally, flux leakage can easily occur during the horizontal reciprocating motion of the flux coating device, causing further flux waste. Current flux coating devices use deep and large flux tanks to hold flux. To ensure that flux is fully and evenly coated on the chip surface, a lot of flux often needs to be put into the flux tank of the flux coating device. Unused flux is then taken out of the tank and scrapped, resulting in a waste of flux.

[0003] Therefore, how to reduce flux waste and improve the coating efficiency of flux coating equipment, thereby reducing the packaging cost of semiconductor structures, is a technical problem that urgently needs to be solved. Summary of the Invention

[0004] This invention provides a flux coating apparatus and a flux coating method to reduce flux waste and improve flux coating efficiency, thereby reducing the packaging cost of semiconductor structures.

[0005] According to some embodiments, the present invention provides a flux coating apparatus, comprising:

[0006] Base;

[0007] A rotating structure is located on the base. The rotating structure includes a first sleeve, a second sleeve, and a rotating shaft. The second sleeve is nested inside the first sleeve, and the rotating shaft is nested inside the second sleeve. There is a receiving groove for accommodating flux between the rotating shaft and the second sleeve. The side wall of the first sleeve has a first notch, and the side wall of the second sleeve has a second notch. The rotating shaft is connected to the first sleeve, and the flux can flow out of the rotating structure after the first notch and the second notch are aligned.

[0008] In some embodiments, the first notch extends along a first direction.

[0009] In some embodiments, the rotating structure further includes:

[0010] A baffle is located on the side wall of the first sleeve, the baffle being able to cover at least part of the first notch and being able to translate along the first direction.

[0011] In some embodiments, the first sleeve extends along the first direction, and the first notch penetrates the sidewall of the first sleeve along the first direction;

[0012] The top of the baffle is connected to the rotating shaft, the sidewall of the baffle is connected to the sidewall of the first notch, and the rotating shaft can move up and down along the first direction.

[0013] In some embodiments, along the first direction, the second sleeve is higher than the first sleeve, and the rotation axis is higher than the second sleeve;

[0014] The top of the baffle is connected to the rotating shaft, which protrudes from the top of the second sleeve.

[0015] In some embodiments, the width of the first notch is equal to the width of the second notch.

[0016] In some embodiments, it also includes:

[0017] A scraper is located outside the rotating structure along a second direction, and the scraper is connected to the side wall of the first sleeve. The second direction intersects the first direction.

[0018] In some embodiments, the scraper includes:

[0019] Base plate;

[0020] The first side plate is perpendicularly connected to the bottom plate via its bottom surface, and the side surface of the first side plate is connected to the side wall of the first sleeve.

[0021] In some embodiments, the base includes an annular sidewall distributed around the outer periphery of the rotating structure and the scraper; the scraper further includes:

[0022] The second side plate is perpendicularly connected to the bottom plate through its bottom surface, and the side surface of the second side plate is connected to the end of the first side plate away from the first sleeve. The second side plate is attached to the surface of the annular side wall.

[0023] In some embodiments, the width of the base plate gradually increases in the direction from the first sleeve to the second side plate.

[0024] According to other embodiments, the present invention also provides a flux coating method, comprising the following steps:

[0025] Provide the chips to be soldered;

[0026] The rotating shaft in the flux coating device described above is driven to rotate, aligning the first notch and the second notch, so that the flux flows from the first notch to the base through the second notch;

[0027] Control the chip to pick up the flux on the base.

[0028] In some embodiments, the first notch extends along a first direction, and the rotating structure further includes a baffle located on the side wall of the first sleeve; before driving the rotating shaft to rotate, the following steps are also included:

[0029] Control the baffle to translate along the first direction and adjust the size of the baffle covering the first gap.

[0030] In some embodiments, the specific steps of driving the rotating shaft in the flux coating apparatus as described above to rotate further include:

[0031] Adjust the rotational speed of the rotating shaft to control the flow rate of the flux flowing out of the receiving tank.

[0032] In some embodiments, the following steps are also included:

[0033] The rotating shaft is driven to rotate, completely offsetting the first notch and the second notch, thus preventing the flux from flowing out of the first notch.

[0034] The flux coating apparatus and method provided by this invention utilize a rotating structure comprising a first sleeve, a second sleeve, and a rotating shaft. The second sleeve is nested inside the first sleeve, and the rotating shaft is nested inside the second sleeve. A receiving groove for accommodating flux is provided between the rotating shaft and the second sleeve. The first sleeve has a first notch, and the second sleeve has a second notch. Rotation of the rotating shaft drives the rotation of the first sleeve. After the first notch on the first sleeve and the second notch on the second sleeve are aligned, the flux can flow from the receiving groove sequentially through the second notch and the first notch to the chip to be soldered. This allows control of the flux flow rate and volume through the rotation of the rotating shaft, achieving flux usage control, reducing flux waste, and lowering chip soldering costs. Furthermore, the flux in this invention is stored in the receiving groove between the rotating shaft and the second sleeve, resulting in a smaller flux quantity and avoiding the problem of flux waste caused by placing too much flux in the coating apparatus. Attached Figure Description

[0035] Appendix Figure 1 This is a three-dimensional structural schematic diagram of the flux coating device in a specific embodiment of the present invention;

[0036] Appendix Figure 2 This is a top view schematic diagram of the flux coating device in a specific embodiment of the present invention;

[0037] Appendix Figure 3 It is attached Figure 2 A schematic diagram of the cross-section at position AA;

[0038] Appendix Figure 4 It is attached Figure 2 A cross-sectional diagram at position BB;

[0039] Appendix Figure 5 This is a flowchart of the flux coating method in a specific embodiment of the present invention. Detailed Implementation

[0040] The specific embodiments of the flux coating apparatus and flux coating method provided by the present invention will be described in detail below with reference to the accompanying drawings.

[0041] This specific embodiment provides a flux coating device, with attachment Figure 1 This is a three-dimensional structural schematic diagram of the flux coating device in a specific embodiment of the present invention, with attached... Figure 2 This is a top view schematic diagram of the flux coating device in a specific embodiment of the present invention, with attached... Figure 3 It is attached Figure 2 A cross-sectional diagram at position AA, attached. Figure 4 It is attached Figure 2 A cross-sectional diagram at position BB. (See diagram below.) Figures 1-4 The flux coating apparatus includes:

[0042] Base 10;

[0043] A rotating structure is located on the base 10. The rotating structure includes a first sleeve 11, a second sleeve 12, and a rotating shaft 13. The second sleeve 12 is nested inside the first sleeve 11, and the rotating shaft 13 is nested inside the second sleeve 12. There is a receiving groove 17 for receiving flux between the rotating shaft 13 and the second sleeve 12. The side wall of the first sleeve 11 has a first notch 15, and the side wall of the second sleeve 12 has a second notch. The rotating shaft 13 is connected to the first sleeve 11. The flux can flow out of the rotating structure after the first notch 15 and the second notch are aligned.

[0044] For example, such as Figures 1-4 As shown, the flux coating device includes a disc-shaped base 10 and a rotating structure located on the base 10. The rotating structure includes a rotating shaft 13, a second sleeve 12 surrounding the outer periphery of the rotating shaft 13, and a first sleeve 11 surrounding the outer periphery of the second sleeve 12. The first sleeve 11, the second sleeve 12, and the rotating shaft 13 are all located on the base 10. The annular groove between the second sleeve 12 and the rotating shaft 13 serves as a receiving groove 17 for receiving the flux. The sidewall of the first sleeve 11 has a first notch 15 extending upward from the bottom of the first sleeve 11, and the sidewall of the second sleeve 12 has a second notch. The rotating shaft 13 is capable of rotating under the drive of a motor or other drive structure, and the rotation of the rotating shaft 13 drives the rotation of the first sleeve 11 connected to the rotating shaft 13. In one example, the second sleeve 12 is fitted against the surface of the first sleeve 11 facing the second sleeve 12 (i.e., the inner surface of the first sleeve 11), and the first sleeve 11 can rotate freely under the drive of the rotating shaft 13. For ease of control, in one example, the second sleeve is not connected to the rotating shaft 13, so the second sleeve 12 will not rotate with the rotation of the rotating shaft 13. In one example, the second sleeve 12 is fixedly connected to the base 10. When the rotating shaft 13 drives the first sleeve 11 to rotate until the first notch 15 on the first sleeve 11 aligns with the second notch on the second sleeve 12, the flux contained in the receiving groove 17 can flow out through the second notch from the first notch 15. In one example, the rotating shaft 13 is a solid rotating shaft, thereby further preventing the flux from leaking out.

[0045] In this specific embodiment, the flux is stored in the receiving groove 17 between the rotating shaft 13 and the second sleeve 12. This embodiment controls whether the flux flows out by controlling the rotation of the rotating shaft 13, and controls the flow rate and amount of flux by controlling the rotation parameters of the rotating shaft 13 (e.g., rotation speed, rotation angle, number of rotations, etc.). This achieves control over the amount of flux used, thus meeting welding requirements while reducing flux waste and lowering chip welding costs. This embodiment controls the flux flow by controlling the rotation of the rotating shaft 13, eliminating the need for reciprocating translation of the rotating structure, improving flux flow efficiency and thus increasing chip welding efficiency. Furthermore, the receiving groove 17 in this embodiment is located between the rotating shaft 13 and the second sleeve 12 and is a continuously distributed annular groove, reducing the difficulty of cleaning the receiving groove 17 and effectively reducing costs caused by cleaning wear.

[0046] In some embodiments, the first notch 15 extends along a first direction D1.

[0047] In some embodiments, the rotating structure further includes:

[0048] A baffle 14 is located on the side wall of the first sleeve 11. The baffle 14 can cover at least part of the first notch 15 and can translate along the first direction D1.

[0049] Specifically, the baffle 14 can be translated along the extension direction of the first notch 15. The baffle 14 can cover at least part of the first notch 15, and the flux flows out from the part of the first notch 15 that is not covered by the baffle 14. Thus, the size of the first notch 15 covered by the baffle 14 can be adjusted by the translational movement of the baffle 14, and the flow rate of the flux can be adjusted so that the needs of soldering (e.g., soldering chips of different sizes) can be met, while avoiding the waste of flux.

[0050] In some embodiments, the first sleeve 11 extends along the first direction D1, and the first notch 15 penetrates the sidewall of the first sleeve 11 along the first direction D1.

[0051] The top of the baffle 14 is connected to the rotating shaft 13, the side wall of the baffle 14 is connected to the side wall of the first notch 15, and the rotating shaft 13 can move up and down along the first direction D1.

[0052] In some embodiments, along the first direction D1, the second sleeve 12 is higher than the first sleeve 11, and the rotating shaft 13 is higher than the second sleeve 12;

[0053] The top end of the baffle 14 is connected to the rotating shaft 13, which protrudes from the top end of the second sleeve 12.

[0054] For example, such as Figures 1-4 As shown, the first sleeve 11, the second sleeve 12, and the rotating shaft 13 all extend along the first direction D1. The height of the second sleeve 12 along the first direction D1 is higher than the height of the first sleeve 11 along the first direction D1, and the height of the rotating shaft 13 along the first direction D1 is higher than the height of the second sleeve 12 along the first direction D1. This allows the second sleeve 12 to protrude from the first sleeve 11 along the first direction D1, and the rotating shaft 13 to protrude from the second sleeve along the first direction D1. This ensures the free rotation of the rotating shaft 13 and simplifies the connection between the baffle 14, the rotating shaft 13, and the first sleeve 11. The baffle 14 can be L-shaped, meaning it includes a first portion located on the side wall of the first sleeve 11 and a second portion perpendicularly connected to the first portion and connected to the top surface of the rotating shaft 13. The first portion of the baffle 14 is located within the first notch, and the sidewall of the first portion is abutted against the sidewall of the first notch. The first portion can rise and fall with the rotation shaft 13, thereby adjusting the size of the first notch 15 covered by the first portion, and thus controlling the flux outflow. For example, when the rotation shaft 13 rises along the first direction D1, the size of the baffle 14 covering the first notch 15 decreases, and when the first notch 15 aligns with the second notch, the flux outflow increases. When the rotation shaft 13 descends along the first direction D1, the size of the baffle 14 covering the first notch 15 increases, and when the first notch 15 aligns with the second notch, the flux outflow decreases.

[0055] In some embodiments, the width of the first notch 15 is equal to the width of the second notch to reduce the amount of flux adhering to the inner surface of the first sleeve 11, thereby further reducing flux waste.

[0056] In some embodiments, the flux coating apparatus further includes:

[0057] The scraper 16 is located outside the rotating structure along the second direction D2. The scraper 16 is connected to the side wall of the first sleeve 11. The second direction D2 intersects the first direction D1.

[0058] In some embodiments, the scraper 16 includes:

[0059] Base plate 162;

[0060] The first side plate 161 is perpendicularly connected to the bottom plate 162 through its bottom surface, and the side surface of the first side plate 161 is connected to the side wall of the first sleeve 11.

[0061] For example, such as Figures 1-4 As shown, the scraper 16 is located on the base 10, and the scraper 16 is located outside the rotating structure along the second direction D2 and connected to the side wall of the first sleeve 11. This allows the scraper 16 to rotate via the first sleeve 11 when the rotating shaft 13 rotates, thus scraping the flux flowing out from the first notch 15 and improving the uniformity of flux distribution on the base 10. By providing a bottom plate 162 connected to the first side plate 161, the contact area between the scraper 16 and the flux can be increased, thereby improving the efficiency of uniformly dispersing the flux. Furthermore, the vertical connection between the bottom plate 162 and the first side plate 161 allows the bottom plate 162 to collect excess flux, further improving the uniformity of flux distribution on the base 10.

[0062] In some embodiments, the base 10 includes an annular sidewall 101, which is distributed around the outer periphery of the rotating structure and the scraper 16; the scraper 16 further includes:

[0063] The second side plate 163 is perpendicularly connected to the bottom plate 162 through its bottom surface, and the side surface of the second side plate 163 is connected to the end of the first side plate 161 away from the first sleeve 11. The second side plate 163 is attached to the surface of the annular side wall 101.

[0064] Specifically, the base 10 includes a support plate 102 and an annular sidewall 101 surrounding the outer periphery of the support portion 102 and connected to the support plate 102. The annular sidewall 101 is seamlessly connected to the support plate 102, thereby preventing flux leakage from the base 10 and further reducing flux waste. The rotating structure and the scraper 16 are both located on the support plate 102. After the first notch 15 is aligned with the second notch, the flux flows from the receiving groove 17 onto the support plate 102. By providing a second side plate 163 connected to the first side plate 161 and the base plate 162, and the second side plate 163 fitting against the inner surface of the annular sidewall 101 (i.e., the surface of the annular sidewall facing the rotating structure), excess flux can be collected better, and the collected flux can be prevented from adhering to the annular sidewall 101 of the base 10, thereby reducing contamination of the annular sidewall 101.

[0065] In some embodiments, the width of the base plate 162 gradually increases in the direction from the first sleeve 11 to the second side plate 163, so that the scraper 16 can fully collect the excess flux, further improving the uniformity of flux distribution on the support plate 102.

[0066] This specific embodiment also provides a flux coating method, attached... Figure 5 This is a flowchart of the flux coating method in a specific embodiment of the present invention. For example... Figure 5 As shown, the flux coating method includes the following steps:

[0067] Step S51: Provide the chip to be soldered;

[0068] Step S52, drive the flux coating device as described above (see Figures 1-4 The rotating shaft 13 in the figure rotates to align the first notch 15 and the second notch, so that the flux flows from the first notch 15 through the second notch to the base 10;

[0069] Step S53: Control the chip to pick up the flux on the base 10.

[0070] In some embodiments, the first notch 15 extends along a first direction D1, and the rotating structure further includes a baffle 14 located on the side wall of the first sleeve 11; before driving the rotating shaft 13 to rotate, the following steps are also included:

[0071] Control the baffle 14 to translate along the first direction D1, and adjust the size of the baffle 14 covering the first notch 15.

[0072] For example, when the baffle 14 is controlled to translate along the first direction D1, such that the size of the baffle 14 covering the first notch 15 increases, the flux outflow decreases when the first notch 15 is aligned with the second notch; when the baffle 14 is controlled to translate along the first direction D1, such that the size of the baffle 14 covering the first notch 15 decreases, the flux outflow increases when the first notch 15 is aligned with the second notch.

[0073] In some embodiments, the specific steps of driving the rotating shaft 13 in the flux coating apparatus as described above to rotate further include:

[0074] Adjust the rotational speed of the rotating shaft 13 to control the flow rate of the flux flowing out of the receiving tank 17.

[0075] For example, when the rotational speed of the rotating shaft 13 increases, the number of times the first notch 15 aligns with the second notch within a preset time increases, and the flux outflow increases; when the rotational speed of the rotating shaft 13 decreases, the number of times the first notch 15 aligns with the second notch within a preset time decreases, and the flux outflow decreases.

[0076] In some embodiments, the flux coating method further includes the following steps:

[0077] The rotating shaft 13 is driven to rotate, completely offsetting the first notch 15 and the second notch, thus preventing the flux from flowing out of the first notch 15.

[0078] For example, when the amount of flux reaches the amount required for chip soldering, the rotating shaft can be driven to rotate so that the first notch 15 and the second notch do not overlap at all (i.e., the projection of the first notch 15 on the side wall of the second sleeve 12 does not overlap at all with the second notch), thereby preventing the flux from flowing out of the first notch 15 and further avoiding the waste of flux.

[0079] The flux coating apparatus and method provided in this specific embodiment utilize a rotating structure comprising a first sleeve, a second sleeve, and a rotating shaft. The second sleeve is nested inside the first sleeve, and the rotating shaft is nested inside the second sleeve. A receiving groove for accommodating flux is provided between the rotating shaft and the second sleeve. The first sleeve has a first notch, and the second sleeve has a second notch. The rotation of the rotating shaft drives the rotation of the first sleeve. After the first notch on the first sleeve and the second notch on the second sleeve are aligned, the flux can flow from the receiving groove sequentially through the second notch and the first notch to the chip to be soldered. This allows control of the flux flow rate by rotating the rotating shaft, achieving flux usage control, reducing flux waste, and lowering chip soldering costs. Furthermore, in this specific embodiment, the flux is stored in the receiving groove between the rotating shaft and the second sleeve, resulting in a smaller flux storage capacity and avoiding the problem of flux waste caused by placing too much flux in the coating apparatus.

[0080] The above description is only a preferred embodiment of the present invention. It should be noted that those skilled in the art can make several improvements and modifications without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A flux coating apparatus, characterized in that, include: Base; A rotating structure is located on the base. The rotating structure includes a first sleeve, a second sleeve, and a rotating shaft. The second sleeve is nested inside the first sleeve, and the rotating shaft is nested inside the second sleeve. There is a receiving groove for accommodating flux between the rotating shaft and the second sleeve. The side wall of the first sleeve has a first notch extending in a first direction, and the side wall of the second sleeve has a second notch. The rotating shaft is connected to the first sleeve, and the flux can flow out of the rotating structure after the first notch and the second notch are aligned. The rotating structure further includes a baffle located on the side wall of the first sleeve, the baffle being able to cover at least part of the first notch and being able to translate along the first direction; The first sleeve extends along the first direction, and the first notch penetrates the side wall of the first sleeve along the first direction. The top end of the baffle is connected to the rotating shaft, the side wall of the baffle is connected to the side wall of the first notch, and the rotating shaft can move up and down along the first direction.

2. The flux coating apparatus according to claim 1, characterized in that, Along the first direction, the second sleeve is higher than the first sleeve, and the rotation axis is higher than the second sleeve; The top of the baffle is connected to the rotating shaft, which protrudes from the top of the second sleeve.

3. The flux coating apparatus according to claim 1, characterized in that, The width of the first notch is equal to the width of the second notch.

4. The flux coating apparatus according to claim 1, characterized in that, Also includes: A scraper is located outside the rotating structure along a second direction, and the scraper is connected to the side wall of the first sleeve. The second direction intersects the first direction.

5. The flux coating apparatus according to claim 4, characterized in that, The scraper includes: Base plate; The first side plate is perpendicularly connected to the bottom plate via its bottom surface, and the side surface of the first side plate is connected to the side wall of the first sleeve.

6. The flux coating apparatus according to claim 5, characterized in that, The base includes an annular sidewall, which is distributed around the outer periphery of the rotating structure and the scraper; the scraper further includes: The second side plate is perpendicularly connected to the bottom plate through its bottom surface, and the side surface of the second side plate is connected to the end of the first side plate away from the first sleeve. The second side plate is attached to the surface of the annular side wall.

7. The flux coating apparatus according to claim 6, characterized in that, The width of the base plate gradually increases in the direction from the first sleeve to the second side plate.

8. A flux coating method, characterized in that, Includes the following steps: Provide the chips to be soldered; Drive the rotating shaft in the flux coating apparatus as described in claim 1 to rotate, align the first notch and the second notch, so that the flux flows from the first notch to the base through the second notch; Control the chip to pick up the flux on the base.

9. The flux coating method according to claim 8, characterized in that, The first notch extends along a first direction, and the rotating structure further includes a baffle located on the side wall of the first sleeve; before driving the rotating shaft to rotate, the following steps are also included: Control the baffle to translate along the first direction and adjust the size of the baffle covering the first gap.

10. The flux coating method according to claim 8, characterized in that, The specific steps for driving the rotating shaft in the flux coating apparatus as described in claim 1 to rotate further include: Adjust the rotational speed of the rotating shaft to control the flow rate of the flux flowing out of the receiving tank.

11. The flux coating method according to claim 8, characterized in that, It also includes the following steps: The rotating shaft is driven to rotate, completely offsetting the first notch and the second notch, thus preventing the flux from flowing out of the first notch.

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