Cleaning device and method for package structure

Abstract

A cleaning device and method for a package structure, for use in cleaning a semiconductor package structure. The cleaning device comprises an upper cavity module (1), a lower cavity module (2), and a control module (5) connected to the upper cavity module (1) and the lower cavity module (2), respectively. The upper cavity module (1) covers the lower cavity module (2) to form a sealed cavity, and the upper cavity module (1) sprays cleaning liquid to a package structure to be cleaned. The lower cavity module (2) comprises a retaining wall unit (11), a raising / lowering mechanism (12), a clamping unit (14), and a lower cavity (16). The retaining wall unit (11) is fixedly arranged on the bottom surface of the lower cavity (16); the raising / lowering mechanism (12) drives the clamping unit (14) to raise and lower; and the clamping unit (14) is arranged in the lower cavity (16), and used for clamping the package structure. The control module (5) is configured to control the raising / lowering mechanism (12) to lower the clamping unit (14) and the clamped package structure to a process position where the clamping unit (14) and the retaining wall unit (11) jointly form a liquid storage cavity. The liquid storage cavity is used for accumulating cleaning liquid to immerse the package structure, allowing thorough cleaning of the package structure. The cleaning device can fully and effectively remove soldering flux residues in package structures.

Description

Cleaning device and cleaning method for packaging structure TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor packaging, in particular to a cleaning device and a cleaning method for packaging structure. BACKGROUND

[0002] A system-on-chip (SoC) is a complex large system integrated in a large chip. Unlike the concept of a system-on-chip, chip heterogeneity proposes to split a large system into several small systems, each of which is made into a small chip, or even a standard small chip, and then re-integrated on the same carrier through a soldering process in the packaging technology. Each small chip is stably connected to the carrier through a plurality of bumps to achieve better performance than a system-on-chip. In the process of packaging the chip, flux (such as rosin) is used to improve the reliability of soldering between the small chip and the carrier. After soldering is completed, the packaging structure after soldering needs to be cleaned to remove residual flux, so as to avoid the adverse effects of residual flux on subsequent packaging processes, thereby affecting product yield.

[0003] With further improvement of packaging density, the size of the packaging structure is continuously reduced, and the gap between the chip and the carrier and the gap between the bumps will become smaller. It is more difficult for the cleaning liquid to enter the small gap between the chip and the carrier. Therefore, the traditional high water pressure flushing under atmospheric pressure is no longer applicable. Therefore, there is an urgent need for a cleaning device and a cleaning method that can effectively remove residual flux from the packaging structure. SUMMARY

[0004] In view of the above problems, the present application aims to provide a cleaning device and a cleaning method for packaging structure, which can effectively remove residual flux from the packaging structure by immersing the packaging structure in a cleaning liquid.

[0005] To achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0006] A cleaning device for packaging structure, comprising an upper cavity module, a lower cavity module and a control module, wherein the control module is connected to the upper cavity module and the lower cavity module respectively;

[0007] The upper cavity module is movably arranged on the lower cavity module, and the upper cavity module is used to cover the lower cavity module to form a closed cavity, and the upper cavity module is used to spray cleaning liquid onto the packaging structure to be cleaned;

[0008] The lower cavity module comprises a retaining wall unit, a lifting mechanism, a clamping unit and a lower cavity body, the retaining wall unit is fixedly arranged on the bottom surface of the lower cavity body, the lifting mechanism is used to drive the clamping unit to lift, and the clamping unit is arranged in the lower cavity body and used to clamp the packaging structure.

[0009] The control module is configured to control the lifting mechanism to drive the clamping unit and the clamped packaging structure to descend to a process position, at this time, the clamping unit and the retaining wall unit jointly form a liquid storage cavity, and the liquid storage cavity is used to accumulate the cleaning liquid to soak the packaging structure.

[0010] The application also provides a cleaning method of a packaging structure, comprising:

[0011] Step S100: the control module keeps the clamping unit at an initial position, and the packaging structure to be cleaned is placed on the clamping unit;

[0012] Step S200: the upper cavity module is closed on the lower cavity module to form a closed cavity;

[0013] Step S300: the clamping unit is lowered from the initial position to a process position, and the upper cavity module sprays the cleaning liquid to the packaging structure;

[0014] Step S400: the packaging structure is soaked in the cleaning liquid in the liquid storage cavity for a predetermined time.

[0015] Compared with the prior art, the application has the following beneficial effects:

[0016] The cleaning device provided by the application is fixedly arranged with a retaining wall unit in a lower cavity body, and an upper cavity module is closed on a lower cavity module to form a closed cavity. When the packaging structure is lowered from an initial position to a process position along with the clamping unit, the clamping unit and the retaining wall unit jointly form a liquid storage cavity, and when the upper cavity module sprays the cleaning liquid to the packaging structure, the liquid storage cavity stores the cleaning liquid. After the spraying is completed, the packaging structure continues to be soaked in the cleaning liquid in the liquid storage cavity, so that the packaging structure can be more effectively and sufficiently cleaned.

[0017] SUMMARY

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only some embodiments of the application, and for those skilled in the art, other drawings can also be obtained without creative labor based on these drawings.

[0019] Fig. 1 is a perspective view of the cleaning device of the application.

[0020] Fig. 2 is a sectional view of the cleaning device of the application.

[0021] Fig. 3 is a cross-sectional view of the cleaning apparatus with the clamping unit in an initial position.

[0022] Fig. 4 is a cross-sectional view of the cleaning apparatus with the clamping unit in a process position.

[0023] Fig. 5 is a flow chart of a cleaning method for a package structure.

[0024] Preferred embodiments of the present application

[0025] The present application will now be described in detail with reference to certain figures and embodiments. The following description is presented to enable any person skilled in the art to make use of the application, and addresses various modifications and variations that can be made by the skilled person to the application. It is to be understood that the detailed description is designed to cover all alternatives and modifications that are reasonably supported by the present application.

[0026] It should be noted that in this specification and the accompanying drawings, similar elements and / or acts are designated with like reference numerals and letters when describing specific embodiments of the present application. The accompanying drawings are only intended to show some non-limiting examples of how the application can be made and used, and should not be construed to limit the scope of the application as defined by the appended claims.

[0027] The technical solutions of the present application will be described clearly and completely below with reference to the drawings. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0028] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate the orientation or positional relationship shown in the drawings, and are only used for the purpose of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", "third" are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0029] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connection", "linking" should be understood in a broad sense, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through intermediate medium, or internal communication of two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0030] In order to make the purpose, technical scheme and advantages of the present application more clear, the embodiments of the present application will be further described in detail below with reference to the drawings.

[0031] Referring to FIG. 1 and FIG. 2, the present application provides a cleaning device. The cleaning device comprises a lower cavity module 1, an upper cavity module 2, a gas extraction pipeline (not shown) and a control module 5 connected with the lower cavity module 1 and the upper cavity module 2 respectively. The upper cavity module 2 is movably connected with the lower cavity module 1, and the upper cavity module 2 is movably arranged on the lower cavity module 1. The gas extraction pipeline is arranged on the lower cavity module 1. When the packaging structure needs to be cleaned, the upper cavity module 2 is driven to descend and cover on the lower cavity module 1 to form a closed chamber. The gas in the closed chamber can be extracted by an external gas extraction pump through the gas extraction pipeline, so that the pressure in the closed chamber is negative pressure. For example, when the pressure in the closed chamber is negative pressure, the upper cavity module 2 sprays cleaning liquid to clean the packaging structure. The cleaning liquid can better enter the gap of the packaging structure, so as to achieve better cleaning effect. The cleaning liquid includes but is not limited to deionized water, liquid containing saponifier, etc. The composition of the cleaning liquid can be selected according to the actual process.

[0032] Further referring to FIG. 3, the lower cavity module 1 comprises a barrier wall unit 11, a lifting mechanism 12, a rotating mechanism 13, a magnetic fluid seal 14, a clamping unit 15, a lower cavity body 16, a cavity bottom plate 17, an elastic pipeline 18 and an elastic pipeline support 19. The lower cavity body 16 is arranged on the cavity bottom plate 17. In the present embodiment, the lower cavity body 16 and the cavity bottom plate 17 can be arranged fixedly, and the upper cavity module 2 is lowered and covers on the lower cavity module 1 to form a closed chamber. It can be understood that in other embodiments, the upper cavity module 2 can also be arranged fixedly, and the lower cavity module 1 moves upward to close with the upper cavity module 2 to form a closed chamber. The lower end 18a of the elastic pipeline 18 is fixed on the bottom of the lower cavity body 16, and the upper end 18b of the elastic pipeline 18 is fixed on the elastic pipeline support 19. The clamping unit 15 is used for clamping the packaging structure. In the present embodiment, the elastic pipeline 18 selects a bellows.

[0033] The retaining wall unit 11 is fixedly arranged in the lower cavity 16. Specifically, the retaining wall unit 11 comprises a surrounding wall 111, a base plate 112 and a supporting seat 113. The surrounding wall 111 is in a ring structure, the surrounding wall 111 is arranged on the base plate 112, the upper end of the supporting seat 113 is arranged on the base plate 112, and the lower end of the supporting seat 113 is fixedly connected with the bottom of the lower cavity 16. The supporting seat 113 is in a columnar body, the elastic pipeline 18 is telescoped in the supporting seat 113, and the elastic pipeline support 19 moves up and down in the elastic pipeline 18.

[0034] The lifting mechanism 12 comprises a second driving source 121, a lifting shaft 122 and a base 123. The lifting shaft 122 is arranged at the output end of the second driving source 121, and the base 123 is arranged at one end of the lifting shaft 122. The second driving source 121 drives the lifting shaft 122 and the base 123 to lift. The second driving source 121 can be a pneumatic cylinder.

[0035] The magnetic fluid seal 14 comprises a magnetic fluid seal inner shaft 141 and a magnetic fluid seal outer ring 142. The magnetic fluid seal outer ring 142 is sleeved on the outer periphery of the magnetic fluid seal inner shaft 141. The magnetic fluid seal outer ring 142 is connected with the bottom of the base 123, and the lower end of the elastic pipeline support 19 is connected with the top of the base 123. The magnetic fluid seal outer ring 142, the base 123 and the elastic pipeline support 19 are connected as a whole, and the second driving source 121 drives the magnetic fluid seal outer ring 142, the base 123 and the elastic pipeline support 19 to lift together.

[0036] The rotating mechanism 13 comprises a first driving source 131 and a rotating shaft 132. The rotating shaft 132 is arranged at the output end of the first driving source 131. The first driving source 131 can be a motor. The lower end of the magnetic fluid seal inner shaft 141 is arranged at the output end of the rotating shaft 132, and the upper end of the magnetic fluid seal inner shaft 141 is connected with the bottom of the clamping unit 15. Therefore, the first driving source 131 drives the magnetic fluid seal inner shaft 141 and the clamping unit 15 to rotate, and the magnetic fluid seal inner shaft 141 and the clamping unit 15 rotate together with the rotating shaft 132 with the encapsulation structure.

[0037] In addition, the magnetic fluid seal outer ring 142 is arranged on the outer periphery of the magnetic fluid seal inner shaft 141. When the magnetic fluid seal outer ring 142 lifts, the magnetic fluid seal inner shaft 141 is lifted, thereby driving the first driving source 131 and the rotating shaft 132 to lift. That is, when the second driving source 121 works, the base 123, the rotating mechanism 13, the magnetic fluid seal 14, the clamping unit 15 and the elastic pipeline support 19 lift at the same time.

[0038] Further, the clamping unit 15 comprises a support column 153, a clamping plate 151 and three clamping pieces 152 arranged on the clamping plate 151 and used for clamping the packaging structure, the clamping plate 151 is arranged on the support column 153, the support column 153 is connected with the upper end of the magnetic fluid seal inner shaft 141, and the support column 153 moves up and down in the elastic pipeline support 19. The bottom surface of the clamping plate 151 is provided with an annular protrusion 1511, and when the packaging structure is lowered to the process position with the clamping unit 15, the outer surface of the annular protrusion 1511 abuts against the inner surface of the support seat 113, so that the clamping unit 15 is clamped with the bottom disc 112, and the retaining wall 111, the bottom disc 112 and the annular protrusion 1511 jointly form the liquid storage cavity 4.

[0039] The support seat 113 is provided with a first liquid discharge hole, the bottom of the lower cavity 16 is provided with a second liquid discharge hole, and a liquid discharge cavity is formed between the support seat 113 and the outer periphery of the elastic pipeline 18, and the first liquid discharge hole is in communication with the lower cavity 16 and the liquid discharge cavity. When the clamping unit 15 is raised from the process position, the cleaning liquid in the liquid storage cavity 4 flows into the liquid discharge cavity and is then discharged to the outside through the first liquid discharge hole and the second liquid discharge hole of the lower cavity 16.

[0040] Specifically, when the packaging structure needs to be cleaned, according to an embodiment of the present application, the packaging structure is placed on the clamping unit 15, the upper cavity module 2 is driven to be lowered and covers the lower cavity module 1 to form a closed cavity, the second driving source 121 drives the lifting shaft 122 to be lowered, and the base 123 and the rotating mechanism 13 are lowered with the lifting shaft 122. When the base 123 moves, the magnetic fluid seal 14 and the clamping unit 15 are lowered with the base 123, the clamping unit 15 with the packaging structure is lowered from the initial position (shown in FIG. 3) to the process position (shown in FIG. 4) and abuts against the inner periphery of the support seat 113, so that the retaining wall 111 of the retaining wall unit 11 and the bottom disc 112 form the liquid storage cavity 4 with the annular protrusion 1511. At the same time, the upper end 18b of the elastic pipeline 18 is lowered with the elastic pipeline support 19. The lower end 18a of the elastic pipeline 18 is fixed, and the elastic pipeline 18 restores to the natural shape or is compressed when the elastic pipeline support 19 is lowered.

[0041] After the packaging structure is lowered to the process position, the closed cavity is pumped to make the pressure in the closed cavity be negative pressure, the upper cavity module 2 sprays the packaging structure, and the cleaning liquid is accumulated in the liquid storage cavity 4 in the spraying process. After the spraying is completed, the cleaning liquid covers the packaging structure, and the packaging structure is soaked in the liquid storage cavity 4 in the negative pressure environment. The soaking environment is set in the negative pressure environment, which can reduce the surface tension of the cleaning liquid, improve the diffusion capacity of the cleaning liquid, make the cleaning liquid more smoothly enter the gap of the packaging structure, and uniformly diffuse in the gap between the bumps and the bumps and between the chips and the carrier.

[0042] After the soaking is completed, gas is input into the closed chamber to break the vacuum environment of the closed chamber, so that the air pressure in the closed chamber reaches normal pressure. In the normal pressure state, the second driving source 121 drives the lifting shaft 122 to rise, and the magnetic fluid seal 14 and the clamping unit 15 rise with the base 123. The clamping unit 15 carries the packaging structure from the process position to the initial position, and the clamping unit 15 is separated from the support seat 113. In the process of rising of the clamping unit 15, the cleaning liquid accumulated in the liquid storage cavity 4 starts to drain and is emptied. When the elastic pipeline support 19 rises, the elastic pipeline 18 is stretched.

[0043] In the embodiment, the elastic pipeline 18 and the elastic pipeline support 19 are in a columnar body structure, which is used to prevent the magnetic fluid seal 14 from being corroded when the cleaning liquid is drained. A certain gap is preset between the top of the elastic pipeline support 19 and the bottom of the clamping unit 15 to avoid interference between the clamping unit 15 and the elastic pipeline support 19 when the clamping unit 15 rotates.

[0044] Further, after the packaging structure rises to the initial position, the first driving source 131 drives the magnetic fluid seal inner shaft 141 and the clamping unit 15 to rotate together. In the normal pressure state, the packaging structure rotates with the clamping unit 15, and the centrifugal force generated by the rotation is used to spin dry the cleaning liquid on the clamping unit 15 and the packaging structure, so as to dry the packaging structure. Alternatively, while the packaging structure is rotating, dry gas (such as N2) is blown to the packaging structure to blow the cleaning liquid on the surface of the packaging structure to the outside of the packaging structure, so as to achieve the purpose of rapid drying. Through the drying process, the cleaning liquid on the surface of the packaging structure is removed, which facilitates the packaging structure to enter the next process, prevents the cleaning liquid from polluting the process environment of the next process, and improves the process safety and stability.

[0045] In other optional embodiments, when the packaging structure is in the initial position, the upper cavity module 2 is driven to descend and cover the lower cavity module 1 to form a closed chamber. The closed chamber is pumped to be in a negative pressure state, and the upper cavity module 2 performs a first spraying operation on the packaging structure. After the first spraying is completed, the closed chamber is broken to restore to a normal pressure state. The clamping unit 15 carries the packaging structure from the initial position (shown in FIG. 3) to the process position (shown in FIG. 4) and abuts against the inner wall of the support seat 113 to form the liquid storage cavity 4. The closed chamber is pumped again to be in a negative pressure state, and the upper cavity module 2 performs a second spraying operation on the packaging structure. During the second spraying, the cleaning liquid is accumulated in the liquid storage cavity 4. After the second spraying is completed, the cleaning liquid covers the packaging structure, and the packaging structure is completely soaked in the cleaning liquid in the liquid storage cavity 4. After the soaking is completed, the closed chamber is broken to restore to a normal pressure state. The clamping unit 15 carries the packaging structure from the process position to the initial position to perform a drying process.

[0046] Further, after the soaking is completed, the clamping unit 15 carries the packaging structure from the process position back to the initial position, and the upper cavity module 2 sprays the packaging structure for the third time under normal pressure. Then, the drying process is performed. Alternatively, the third spraying can also be performed under negative pressure.

[0047] Illustratively, after the packaging structure is sprayed with the cleaning liquid at the initial position, the packaging structure is kept still for a preset time, so that the cleaning liquid enters the gap of the packaging structure and soaks the contaminants in the gap, which helps to promote the complete cleaning of the residual contaminants.

[0048] In an alternative embodiment, after the packaging structure is lowered to the process position, the closed cavity is not limited to negative pressure, for example, it can also be normal pressure. The upper cavity module 2 sprays the packaging structure first, and during the spraying process, the cleaning liquid accumulates in the liquid storage cavity 4. After the spraying is completed, the cleaning liquid covers the packaging structure, and then the closed cavity is pumped to negative pressure, so that the packaging structure is soaked in the liquid storage cavity 4 under negative pressure, effectively cleaning the packaging structure.

[0049] It should be noted that when the packaging structure is soaked in the cleaning liquid in the liquid storage cavity, the closed cavity is not limited to negative pressure, for example, it can also be normal pressure. In addition, when the upper cavity module 2 sprays the packaging structure, the closed cavity is also not limited to negative pressure. The clamping unit 15 carrying the packaging structure can be lifted or lowered in a negative pressure environment or under normal pressure. It should be understood that in order to further ensure the cleaning effect, the packaging structure can be sprayed multiple times at the initial position during the cleaning process to ensure the cleaning effect. The number of repetitions can be selected according to the process requirements.

[0050] In an alternative embodiment, the cavity bottom plate 17 is provided with four guide columns 171, and the rotating mechanism 13 is slidingly arranged on the guide columns 171 through the connecting piece. The rotating mechanism 13 can stably ascend and descend along the guide columns 171, so that the clamping unit 15 drives the packaging structure to stably ascend and descend as a whole, effectively avoiding the situation that the clamping unit 15 ascends and descends obliquely.

[0051] In an alternative embodiment, the outer surface of the annular protrusion 1511 is provided with a first sealing ring. After the packaging structure is lowered to the process position, the first sealing ring abuts against the inner surface of the support seat 113. The first sealing ring is used to seal the gap between the clamping unit 15 and the retaining wall unit 11, preventing the cleaning liquid from leaking.

[0052] Further, the lower surface of the base 123 is provided with a ring-shaped second sealing ring. When the packaging structure is at the process position, the second sealing ring elastically abuts against the cavity bottom plate 17. The second sealing ring is used to prevent external gas from entering the closed cavity.

[0053] Further, the upper surface of the base 123 is provided with a third annular sealing ring, and the third sealing ring elastically abuts on the bottom of the lower cavity 16 when the packaging structure is in the initial position, and the third sealing ring is used to prevent external gas from entering the closed chamber.

[0054] In an optional embodiment, the lifting mechanism 12 includes at least two second driving sources 121, and the at least two second driving sources 121 are respectively arranged on the cavity bottom plate 17. The control module 5 drives the at least two second driving sources 121 to work synchronously, and the clamping unit 15 drives the packaging structure to stably lift as a whole, thereby effectively avoiding the situation that the clamping unit 15 tilts to lift.

[0055] For example, the cleaning device further includes at least two third driving sources 3, and the at least two third driving sources 3 are respectively arranged on the cavity bottom plate 17. The upper cavity module 2 is arranged at the output end of the third driving source 3. The control module 5 drives the at least two third driving sources 3 to work synchronously, and the third driving source drives the upper cavity module 2 to lift, and the upper cavity module 2 stably lifts as a whole, thereby effectively avoiding the situation that the upper cavity module 2 tilts to lift.

[0056] In the process of packaging the chip, flux (for example, rosin) is used to improve the reliability of the welding between the chip and the carrier. For example, in the flip chip, the packaging structure includes a carrier and at least one small chip, and the small chip is flip-chip welded on the carrier by bumps. As described in the background, when the small chip is flip-chip welded on the carrier, most of the flux will volatilize at high temperature, but part of the flux and other pollutants will still remain in the gap between the small chip and the carrier and the gap between the bumps.

[0057] In order to further improve the cleaning effect of the packaging structure, in an optional embodiment, when the packaging structure is soaked, the control module 5 changes the pressure in the closed chamber, for example, breaks the vacuum environment in the closed chamber. The change of the pressure in the closed chamber in the process of breaking the vacuum causes the cleaning liquid on the surface of the packaging structure to press into the gap between the small chip and the carrier and the gap between the bumps, and the cleaning liquid in the gap reciprocates and oscillates due to the pressure fluctuation in the closed chamber, which can further remove the small bubbles between the cleaning liquid and the flux, increase the effective contact area between the cleaning liquid and the flux, and improve the cleaning effect.

[0058] Optionally, when the packaging structure is soaked, the pressure in the closed chamber can be continuously reduced to change the pressure in the chamber, so that the cleaning liquid in the storage cavity 4 reciprocates and oscillates in the gap between the small chip and the carrier and the gap between the bumps.

[0059] It should be noted that the pressure in the closed chamber can be continuously changed or intermittently changed, and the pressure in the closed chamber can be increased from negative pressure to normal pressure or positive pressure, or decreased from positive pressure to normal pressure or negative pressure. The fluctuation of the pressure in the closed chamber causes the cleaning liquid in the gap to oscillate, thereby improving the cleaning effect.

[0060] If the closed chamber is broken from vacuum to positive pressure, the cleaning liquid is prone to generate bubbles due to the pressure in the closed chamber being greater than the pressure outside the closed chamber. Preferably, the change of the pressure in the chamber is carried out when the closed chamber is broken from vacuum to normal pressure or still maintained at negative pressure. Further, the periodic fluctuation of the pressure in the closed chamber can more effectively improve the immersion cleaning effect.

[0061] In summary, the cleaning device of the embodiment adds a retaining wall unit 11 in the lower cavity 16, and the retaining wall unit 11 includes a surrounding wall 111, a bottom disc 112, and a support seat 113. The upper cavity module 2 is covered on the lower cavity module 1 to form a closed chamber. When the encapsulation structure is lowered to the process position with the encapsulation structure, the clamping unit 15 abuts against the inner surface of the support seat 113 to form a liquid storage cavity 4 together with the surrounding wall 111 and the bottom disc 112. When the upper cavity module 2 sprays cleaning liquid to the encapsulation structure, the closed chamber maintains a negative pressure state. During the process of spraying cleaning liquid to the encapsulation structure by the upper cavity module 2, the liquid storage cavity 4 stores the cleaning liquid. After the spraying is completed, the encapsulation structure is further immersed in the liquid storage cavity 4 to clean the encapsulation structure more effectively and sufficiently.

[0062] Corresponding to the above-mentioned cleaning device of the encapsulation structure, the application also proposes a cleaning method of the encapsulation structure, and the cleaning method of the encapsulation structure comprises the following steps:

[0063] Step S100: The control module keeps the clamping unit in an initial position, and places the encapsulation structure to be cleaned on the clamping unit.

[0064] Specifically, the encapsulation structure to be cleaned is placed on the clamping unit 15, and the air pressure in the upper cavity module 2 and the lower cavity module 1 is in a normal pressure state at this time.

[0065] Step S200: The upper cavity module is covered on the lower cavity module to form a closed chamber.

[0066] Specifically, the cleaning device further comprises two third driving sources 3, and the two third driving sources 3 are arranged on the cavity bottom plate 17. The upper cavity module 2 is arranged at the output end of the third driving source 3. The control module 5 drives the two third driving sources 3 to work synchronously. The third driving source 3 drives the upper cavity module 2 to ascend and descend. The upper cavity module 2 is driven to descend and cover on the lower cavity module 1 to form a closed chamber.

[0067] Step S300: The clamping unit is lowered from the initial position to the process position, and the upper cavity module sprays cleaning liquid to the encapsulation structure.

[0068] Specifically, after the packaging structure is lowered to the process position, the enclosed cavity can be pumped to have a negative pressure, and the upper cavity module 2 sprays the packaging structure. During the spraying process, the cleaning liquid is accumulated in the liquid storage cavity 4. It should be noted that the spraying process mentioned in the present application is not limited to be performed in a negative pressure environment, for example, it can also be performed in a normal pressure environment.

[0069] Step S400: soaking the packaging structure in the cleaning liquid in the liquid storage cavity for a predetermined time.

[0070] Optionally, the cleaning liquid covers the packaging structure, and the pressure in the enclosed cavity is maintained at a negative pressure. The packaging structure is completely soaked in the cleaning liquid in the liquid storage cavity 4 in the negative pressure environment, and the packaging structure is effectively cleaned.

[0071] Optionally, between the step S200 and the step S300, the following step is further included: the upper cavity module 2 sprays the cleaning liquid to the packaging structure when the packaging structure is in the initial position. Preferably, before the upper cavity module 2 sprays the cleaning liquid to the packaging structure, the enclosed cavity is pumped to have a negative pressure, or the upper cavity module 2 sprays the cleaning liquid to the packaging structure, and then the enclosed cavity is pumped to have a negative pressure. The packaging structure is maintained stationary for a predetermined time, so that the cleaning liquid enters the gap of the packaging structure to clean the packaging structure.

[0072] Pumping the enclosed cavity can pump out the residual gas in the packaging structure, so that the gap of the packaging structure is filled with the cleaning liquid, thereby ensuring the cleaning effect of the packaging structure. At the same time, after the cleaning liquid is sprayed, the cleaning environment of the packaging structure is set to a negative pressure condition, which can reduce the surface tension of the cleaning liquid, improve the diffusion ability of the cleaning liquid, and make the cleaning liquid more smoothly enter the gap of the packaging structure and uniformly diffuse in the gap between the bumps and the bumps and between the chip and the carrier. The packaging structure is maintained stationary for a predetermined time in the negative pressure environment, so that the bubbles in the gap of the packaging structure have enough time to escape from the packaging structure, and the cleaning liquid has enough time to enter the gap of the packaging structure, thereby achieving a better cleaning effect.

[0073] Further, during the process of spraying the cleaning liquid to the packaging structure in the initial position, the packaging structure can be selected to be stationary or to rotate at a predetermined rotational speed. It should be understood that the predetermined rotational speed in the present application can be selected to be a low rotational speed, for example, the predetermined rotational speed is less than or equal to 600 rpm. Selecting the packaging structure to be stationary or to rotate at a low rotational speed can effectively prevent the cleaning liquid from being directly thrown out of the packaging structure due to the large centrifugal force of high rotational speed, and effectively avoid the situation that the cleaning liquid is thrown out of the packaging structure without entering the gap of the packaging structure to be cleaned for effective cleaning.

[0074] Further, the packaging structure in the initial position further comprises: spraying the packaging structure with cleaning liquid again, and changing the pressure in the closed chamber at least once during the spraying of the cleaning liquid; and keeping the packaging structure static for a preset time after the pressure stops changing.

[0075] During the formation of the pressure difference in the closed chamber, the force on the cleaning liquid changes, and thus the position of the cleaning liquid changes, so that the cleaning liquid is more likely to enter the gap of the packaging structure, dissolve the contaminants, and thus facilitate the cleaning liquid to completely clean the contaminants, thereby further improving the cleaning effect.

[0076] The number of times the pressure in the closed chamber changes can be selected according to actual process requirements, which is not limited in the present application. It should be understood that, in order to improve the cleaning efficiency, the number of times the pressure changes can be as many as possible, so that the rate at which the cleaning liquid enters the gap of the packaging structure is accelerated during the process in which the pressure in the closed chamber changes constantly, and after the cleaning liquid completely dissolves the contaminants, the cleaning liquid is accelerated to be discharged from the packaging structure. Alternatively, the pressure in the closed chamber fluctuates periodically, and the pressure in the closed chamber is in a negative pressure state before and after changing.

[0077] Further, the cleaning method further comprises steps S500: the clamping unit is raised from the process position to the initial position; and S600: a drying process, the drying process comprising: inputting a gas into the closed chamber to make the gas pressure in the closed chamber reach an atmospheric pressure, rotating the packaging structure in the atmospheric pressure state, and / or blowing dry gas to the packaging structure.

[0078] Specifically, after the packaging structure is raised to the initial position, the first driving source 131 drives the magnetic fluid seal inner shaft 141 and the clamping unit 15 to rotate together, and in the atmospheric pressure state, the packaging structure rotates with the clamping unit 15, and the centrifugal force generated by the rotation is used to spin dry the cleaning liquid on the clamping unit 15 and the packaging structure, so as to dry the packaging structure.

[0079] In other alternative embodiments, dry gas (such as N2) is blown to the packaging structure while the packaging structure is rotating, so as to blow the cleaning liquid on the surface of the packaging structure to the outside of the packaging structure, so as to achieve the purpose of rapid drying.

[0080] Illustratively, the step S500 further comprises: after the clamping unit is raised from the process position to the initial position, the upper cavity module sprays the packaging structure with cleaning liquid to clean the packaging structure.

[0081] Optionally, after step S600, step S500a is performed, and after step S500a, step S600 is performed, and steps S500a and S600 are repeated multiple times.

[0082] Optionally, after step S600, step S500a is performed, and after step S500a, step S600 is performed, and steps S500a and S600 are repeated multiple times.

[0083] To further improve the cleaning effect of the packaging structure, in an optional embodiment, in step S400, when the packaging structure is soaked, the control module changes the pressure of the closed chamber at least once. The change of the pressure in the closed chamber causes the cleaning liquid on the surface of the packaging structure to press into the gap between the small chips and the carrier and the gap between the bumps, and due to the pressure fluctuation of the closed chamber, the cleaning liquid in the gap realizes reciprocating oscillation, which can further remove small bubbles between the cleaning liquid and the flux, increase the effective contact area between the cleaning liquid and the flux, and improve the cleaning effect.

[0084] It should be noted that the pressure in the closed chamber can be continuously changed or intermittently changed. Preferably, the closed chamber is kept in a negative pressure state, and the pressure of the closed chamber is periodically fluctuated.

[0085] The above has described the basic concept. It is obvious that the above application disclosure is only used as an example and does not limit the application. Although it is not explicitly stated here, those skilled in the art can make various modifications, improvements and corrections to the application. Such modifications, improvements and corrections are suggested in the application, so such modifications, improvements and corrections still belong to the spirit and scope of the exemplary embodiments of the application.

[0086] At the same time, specific words are used in the application to describe the embodiments of the application. For example, "one embodiment", "an embodiment", and / or "some embodiments" means a certain feature, structure or characteristic related to at least one embodiment of the application. Therefore, it should be emphasized and noted that the "one embodiment" or "one embodiment" or "one alternative embodiment" mentioned in different places in the specification does not necessarily refer to the same embodiment. In addition, some features, structures or characteristics in one or more embodiments of the application can be properly combined.

[0087] It should be appreciated that, for this and other reasons, the features of the application are capable of independent use apart from the disclosure of a single embodiment. Thus, regardless of the content of the foregoing description or the embodiments disclosed herein, a single feature can be set forth and claimed independently of a combination with other features set forth. It is not necessary for every means or feature described herein to be present in every embodiment. Further, although process steps, algorithms or methods can be described or implied in a certain order, it is not necessary that each such process step be carried out in the described order, but rather, the description should be understood to include any and all combinations of the described processes, algorithms or methods, and that the ordering of steps in the embodiments can be customized based on the actual implementation.

Claims

1. A cleaning apparatus for a package structure, characterized by, The upper cavity module, the lower cavity module and the control module are connected respectively; The upper cavity module is movably arranged on the lower cavity module, and is used for covering the lower cavity module to form a closed cavity and spraying cleaning liquid on the packaging structure to be cleaned; The lower cavity module comprises a retaining wall unit, a lifting mechanism, a clamping unit and a lower cavity body, the retaining wall unit is fixedly arranged on the bottom surface of the lower cavity body, the lifting mechanism is used for driving the clamping unit to lift, the clamping unit is arranged in the lower cavity body, and the clamping unit is used for clamping the packaging structure; The control module is configured to control the lifting mechanism to drive the clamping unit and the clamped packaging structure to descend to a process position, at this time, the clamping unit and the retaining wall unit jointly form a liquid storage cavity, and the liquid storage cavity is used for accumulating the cleaning liquid to soak the packaging structure.

2. The apparatus for cleaning a package structure according to claim 1, wherein The retaining wall unit comprises a surrounding wall, a base plate and a support seat, the surrounding wall is arranged on the base plate, the support seat is in the form of a columnar body, the upper end of the support seat is arranged on the base plate, and the lower end of the support seat is arranged on the bottom surface of the lower cavity body, when the packaging structure descends to the process position, the clamping unit abuts against the inner surface of the support seat and jointly forms the liquid storage cavity with the surrounding wall and the base plate.

3. The apparatus for cleaning a package structure according to claim 2, wherein The clamping unit comprises a clamping plate and a clamping piece arranged on the clamping plate, the bottom surface of the clamping plate is provided with an annular protrusion, and when the clamping unit drives the packaging structure to descend to the process position, the annular protrusion abuts against the inner surface of the support seat.

4. The apparatus for cleaning a package structure according to claim 3, wherein A first sealing ring is arranged on the outer surface of the annular protrusion, and when the clamping unit drives the packaging structure to descend to the process position, the first sealing ring abuts against the inner surface of the support seat.

5. The apparatus for cleaning a package structure of claim 3, wherein The lower cavity module further comprises a rotating mechanism, the rotating mechanism is arranged on the output end of the lifting mechanism, and the clamping unit is arranged on the output end of the rotating mechanism.

6. The apparatus for cleaning a package structure of claim 5, wherein The rotating mechanism comprises a first driving source and a rotating shaft, the rotating shaft is arranged on the output end of the first driving source, the lower cavity module further comprises a magnetic fluid seal, the magnetic fluid seal comprises a magnetic fluid seal inner shaft and a magnetic fluid seal outer ring, and the magnetic fluid seal outer ring is sleeved on the outer periphery of the magnetic fluid seal inner shaft; The upper end of the magnetic fluid seal inner shaft is connected with the bottom of the clamping unit, and the lower end of the magnetic fluid seal inner shaft is arranged on the output end of the rotating shaft.

7. The apparatus for cleaning a package structure of claim 6, wherein The lifting mechanism comprises a second driving source, a lifting shaft and a base, the lifting shaft is arranged on the output end of the second driving source, and the base is arranged on one end of the lifting shaft; The upper end of the magnetic fluid seal outer ring is connected with the bottom of the base.

8. The apparatus for cleaning a package structure of claim 7, wherein The lower cavity module further comprises an elastic pipeline and an elastic pipeline support, the bottom of the elastic pipeline support is fixed on the base, a certain gap is preset between the top of the elastic pipeline support and the bottom of the clamping unit, the lower end of the elastic pipeline is fixed on the lower cavity body, and the upper end of the elastic pipeline is fixed on the elastic pipeline support.

9. The apparatus for cleaning a package structure of claim 7, wherein The lower cavity module also includes a cavity base plate, the lower cavity is disposed on the cavity base plate, and the lower surface of the base is provided with an annular second sealing ring. When the packaging structure is lowered to the process position, the second sealing ring elastically abuts against the cavity base plate.

10. The apparatus for cleaning a package structure of claim 7, wherein The upper surface of the base is provided with an annular third sealing ring. When the encapsulation structure is in the initial position, the third sealing ring elastically abuts against the bottom of the lower cavity.

11. The cleaning apparatus for the packaging structure according to claim 8, characterized in that, The support base has a first drain hole, and the bottom of the lower cavity has a second drain hole. The outer periphery of the support base and the elastic pipe are closed to form a drain cavity. The first drain hole is connected to the lower cavity and the drain cavity.

12. The apparatus for cleaning a package structure of claim 1, wherein The control module is used to change the pressure of the sealed chamber when the encapsulation structure is immersed in the cleaning fluid in the reservoir.

13. The apparatus for cleaning a package structure of claim 12, wherein The pressure in the enclosed chamber fluctuates periodically.

14. A cleaning method applied to the cleaning apparatus according to any one of claims 1 to 13, characterized by, include: Step S100: The control module keeps the clamping unit in the initial position and places the package structure to be cleaned on the clamping unit; Step S200: The upper cavity module is closed onto the lower cavity module to form a sealed chamber; Step S300: The clamping unit descends from the initial position to the process position, and the upper cavity module sprays cleaning fluid onto the packaging structure; Step S400: Immerse the encapsulation structure in the cleaning solution within the liquid storage chamber for a predetermined time.

15. The cleaning method according to claim 14, wherein Step S300 further includes: after the clamping unit descends from the initial position to the process position, it evacuates the closed chamber to make the pressure inside the closed chamber negative.

16. The cleaning method according to claim 14, wherein Between steps S200 and S300, the method further includes: bringing the pressure inside the sealed cavity to atmospheric pressure, and spraying cleaning fluid onto the encapsulation structure from the upper cavity module.

17. The cleaning method of claim 14, wherein, Between steps S200 and S300, the process further includes: spraying cleaning fluid onto the packaging structure; evacuating the sealed chamber to make the pressure inside the sealed chamber reach a negative pressure; and keeping the packaging structure stationary for a preset time to allow the cleaning fluid to enter the gaps in the packaging structure and clean the packaging structure.

18. The cleaning method according to claim 17, wherein Also includes: Spray the cleaning fluid onto the encapsulation structure again, and during the spraying process, change the pressure inside the sealed chamber at least once. After the pressure stops changing, the encapsulation structure remains stationary for a preset time.

19. The cleaning method according to claim 18, wherein The pressure inside the sealed chamber was negative both before and after the change.

20. The cleaning method of claim 14, wherein, It also includes step S500: the clamping unit returns from the process position to the initial position; S600: a drying process, the drying process including: inputting gas into the sealed chamber to make the gas pressure in the sealed chamber reach atmospheric pressure, rotating the packaging structure under atmospheric pressure, and / or blowing drying gas into the packaging structure.

21. The cleaning method according to claim 20, wherein, Between step S500 and step S600, step S500a is also included: evacuating the sealed chamber to make the pressure inside the sealed chamber reach negative pressure; the upper cavity module sprays cleaning fluid onto the packaging structure; and keeping the packaging structure stationary for a preset time to allow the cleaning fluid to enter the gaps of the packaging structure to clean the packaging structure.

22. The cleaning method of claim 20, wherein, After step S600, step S500a is further included: the closed chamber is pumped to make the pressure in the closed chamber reach a negative pressure; the upper cavity module sprays cleaning liquid to the packaging structure; the packaging structure is kept static for a preset time, so that the cleaning liquid enters the gap of the packaging structure to clean the packaging structure, and then step S600 is performed.

23. The cleaning method of claim 20, wherein, The step S500 further includes: after the clamping unit is lifted from the process position to the initial position, the upper cavity module sprays cleaning liquid to the packaging structure to clean the packaging structure.

24. The cleaning method of claim 14, wherein, The pressure in the closed chamber is changed at least once while the packaging structure is kept soaking in the cleaning liquid in the liquid storage cavity.

25. The cleaning method according to claim 24, wherein, The pressure in the closed chamber fluctuates periodically.

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