A semiconductor package substrate cleaning device and method

Abstract

The present invention relates to the technical field of semiconductor packaging equipment, and provides a semiconductor packaging substrate cleaning device and method. A driving unit drives a clamping unit to clamp a substrate and drive the lifting and jitter of a substrate platform. The stacked carrier and substrate platform are directionally guided by guide rods connected to the carrier. A jacking plate connected to the driving unit drives the substrate platform to move in a lifting manner along the direction of the guide rods. The guide rods are distributed at the corners of the carrier. A plurality of flanges connected to the oppositely arranged guide rods are staggered, and the flanges are located in the upper middle part of the guide rods. A compression spring is also connected between the carrier and the substrate platform. During the chip bonding process, the driving cylinder continues to jack up so that the substrate platform abuts against the flanges on the guide rods, and the cooperation with the compression spring causes the substrate to slightly shake to help air bubbles escape. Shaking the substrate can utilize gravity to help the air bubbles move upward and leave the solder.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor packaging equipment, and particularly relates to a semiconductor packaging substrate cleaning device and method. Background Art

[0002] In the field of semiconductor packaging, a substrate is a carrier for supporting chips and connecting to external circuits. During the entire semiconductor packaging process, a large amount of substances and abrasive particles of the substrate adhere to the substrate after processes such as die bonding and wire bonding. A contact cleaning method is usually adopted, but the contact method will cause the substrate to be pressed and deformed, resulting in problems with the circuit connection between the chip and the substrate. During the die bonding process, a flowing solder is used to fix the chip. The solder is applied to the pads on the substrate or the leads of the chip. The chip is placed on the substrate, and the solder is melted by heating to fix the chip in the correct position. The solder solidifies after cooling to form a firm mechanical and electrical connection. Since the adhesive used is flowing, air will be involved during the process of applying the solder and will melt during the subsequent heating process to form a liquid state. The air trapped in the solder will form bubbles, which will not only affect its adhesion force but also cause open circuits or high resistance in the circuit, affecting the performance of semiconductor devices. It is also inconvenient for later cleaning. Therefore, we propose a semiconductor packaging substrate cleaning device and method. Summary of the Invention

[0003] (I) Technical Problems to be Solved

[0004] In view of the deficiencies of the prior art, the present invention provides a semiconductor packaging substrate cleaning device and method, which overcomes the deficiencies of the prior art, is reasonably designed, has a compact structure, and solves the problems raised in the background art.

[0005] (II) Technical Solutions

[0006] To achieve the above objectives, the present invention is realized through the following technical solutions:

[0007] A semiconductor packaging substrate cleaning device includes a base, a carrier table, and a substrate platform, including a driving unit and a clamping unit. The driving unit drives the clamping unit to clamp the substrate and drives the lifting and shaking of the substrate platform. The stacked carrier table and substrate platform are directionally guided by guide rods connected to the carrier table. The lifting plate connected to the driving unit drives the substrate platform to move in a lifting manner along the direction of the guide rods. The guide rods are distributed at the corners of the carrier table, and a plurality of flanges connected to the oppositely arranged guide rods are staggered, and the flanges are located in the upper middle part of the guide rods. A compression spring is also connected between the carrier table and the substrate platform. It further includes a cleaning head with ultrasonic oscillation that slides along the direction of the substrate to ensure the cleanliness of the substrate.

[0008] Preferably, the clamping unit includes a plurality of grippers mounted on the rotating shaft, and the same baffle is connected between the grippers. The baffle surrounds the substrate to prevent the solder from flowing out of the substrate.

[0009] Preferably, the clamping unit further includes a first linkage rod and a second linkage rod connected to the rotating shaft, and the first linkage rod and the second linkage rod are hinged.

[0010] Preferably, the driving unit includes a driving cylinder, a driving rod is provided at the output end of the driving cylinder, a pair of transmission rods are hinged on the driving rod, and a connecting block connected to the rotating shaft is connected to the side end of the transmission rod far from the driving rod.

[0011] Preferably, a platform transverse groove is provided on the substrate platform for the first linkage rod and the second linkage rod to pass through, and a stage cutting groove is provided on the stage for the driving unit to be connected and matched.

[0012] Preferably, a moving cylinder is further provided on the base, the moving cylinder drives the cleaning head to slide through a slide rail and a slider, and a vacuum tube is connected to the cleaning head.

[0013] Preferably, the cleaning head includes three air inlet channels on both sides and a central vacuum discharge channel separated by a partition inside. Ultrasonic oscillators are installed at the air inlet channels, and a conical adsorption channel is provided at the vacuum discharge channel.

[0014] Preferably, it includes the following steps:

[0015] S1. Chip placement: First, the operator or automated equipment precisely places the chip at a predetermined position on the substrate to ensure accurate alignment.

[0016] S2. Substrate fixation: Next, the gripper or fixture firmly fixes the substrate in place to prevent movement in subsequent steps.

[0017] S3. Substrate movement: Then, the substrate is controlled to approach the chip by an accurate drive system and placed on the chip to ensure the relative position between the two is accurate.

[0018] S4. Solder application: Solder is applied between the chip and the substrate, which is usually done by solder paste printing or pre-placing solder balls to ensure uniform distribution of the solder.

[0019] S5. Heating: The substrate and the chip are heated to make the solder reach the melting point and melt into a liquid state to facilitate the formation of good solder joints.

[0020] S6, Slight shaking: When the solder is in a liquid state, the substrate platform 4 is further lifted by driving the cylinder 31 so that it abuts against the flange 51 on the guide rod 5, and the shrinkage spring is cooperated to make the substrate 6 shake slightly. The purpose of this is to help the bubbles escape from the solder and ensure good contact between the chip and the substrate.

[0021] S7, Cooling and curing: After the bubbles escape, stop shaking the substrate and let the solder cool and cure. The cured solder forms a solid solder joint, firmly fixing the chip on the substrate.

[0022] S8, Substrate cleaning: Finally, the cleaning head reciprocates through the cylinder, and at the same time generates ultrasonic oscillation to separate the fine particles on the substrate. The vacuum pump generates a vacuum to remove the separated particles, ensuring that the surface of the substrate is clean and pollution-free.

[0023] (III) Beneficial effects

[0024] The embodiment of the present invention provides a semiconductor package substrate cleaning device and method. It has the following beneficial effects:

[0025] 1. The traditional cleaning device removes fine particles in a contact manner. However, the contact method will cause the substrate to be pressed and deformed. Adopting the method of sucking the particles on the substrate by ultrasonic oscillation can avoid the above problems.

[0026] 2. Reducing chip handling: Chips are usually much smaller and more fragile than substrates. By moving the substrate while keeping the chip fixed, the mechanical stress on the chip can be reduced, and the risk of chip damage can be lowered.

[0027] 3. Adapting to different chip sizes: During the production process, chips of different sizes or shapes need to be processed. Keeping the chip fixed and moving the substrate is easier to adapt to this change.

[0028] 4. Facilitating automation: In an automated system, it is easier to design a robotic arm or conveyor system that moves the substrate, especially when the chip is placed on a fixed tray or carrier.

[0029] 5. Solder bubble treatment: During the chip bonding process, the substrate platform is further lifted by driving the cylinder so that it abuts against the flange on the guide rod, and the shrinkage spring is cooperated to make the substrate shake slightly to help the bubbles escape. Shaking the substrate can break the surface tension of the bubbles, making it easier for them to escape. At the same time, shaking the substrate can utilize gravity to help the bubbles move upward and leave the solder. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic structural diagram of the present invention;

[0031] Figure 2 It is a partial schematic diagram of the present invention;

[0032] Figure 3 Is a three-dimensional schematic diagram of the bottom of the present invention Figure 2 ;

[0033] Figure 4 Is a three-dimensional schematic diagram of one side of the present invention Figure 2 ;

[0034] Figure 5 Is a schematic diagram of the driving unit of the present invention

[0035] Figure 6 Is a schematic diagram of the carrier stage and the substrate platform of the present invention

[0036] Figure 7 Is a schematic diagram of the guide rod of the present invention

[0037] Figure 8 Is a schematic diagram of the cleaning head of the present invention

[0038] In the figure: 1, base; 11, cleaning head; 12, vacuum tube; 13, moving cylinder; 2, carrier stage; 21, carrier stage cutting groove; 3, driving unit; 31, driving cylinder; 32, driving rod; 33, transmission rod; 34, connecting block; 35, lifting plate; 4, substrate platform; 41, rotating shaft; 42, gripper; 43, first linkage rod; 44, second linkage rod; 45, platform transverse groove; 5, guide rod; 51, flange; 6, substrate Detailed implementation manners

[0039] In order to make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without making creative efforts shall fall within the protection scope of the present invention

[0040] Refer to the attached Figure 1-8A semiconductor packaging substrate cleaning device includes a base 1, a carrier 2, a substrate platform 4, a driving unit 3 and a clamping unit, the clamping unit includes a plurality of grippers 42 mounted on a rotating shaft 41, and the grippers 42 are also connected to a baffle, the baffle surrounds a substrate 6 to prevent solder from flowing out of the substrate 6, and also includes a first linkage rod 43 and a second linkage rod 44 connected to the rotating shaft 41, the first linkage rod 43 and the second linkage rod 44 are hinged, the driving unit 3 drives the clamping unit to clamp the substrate 6 and drives the lifting and shaking of the substrate platform 4, the stacked carrier 2 and the substrate platform 4 are guided in their directions by a guide rod 5 connected to the carrier 2, and the top connected to the driving unit 3 The lifting plate 35 drives the substrate platform 4 to move up and down in the direction of the guide rod 5. The driving unit 3 includes a driving cylinder 31. A driving rod 32 is provided at the output end of the driving cylinder 31. A pair of transmission rods 33 are hinged on the driving rod 32. The side ends of the transmission rods 33 away from the driving rods 32 are connected to connection blocks 34 connected to the rotating shaft 41. The guide rods 5 are distributed at the corners of the carrier 2. Several flanges 51 connected to the relatively arranged guide rods 5 are staggered, and the flanges 51 are located in the middle and upper part of the guide rods 5. A contraction spring is also connected between the carrier 2 and the substrate platform 4. It also includes a cleaning head 11 with ultrasonic oscillation that slides in the direction of the substrate 6 to ensure the cleanliness of the substrate.

[0041] Specific reference Figure 2 and attached Figure 5 , the driving cylinder 31 lifts and pushes the driving rod 32 and the transmission rod 33. At this time, the transmission rod 33 is hinged and continues to lift the transmission rod 33 to drive the shaft 41 to rotate. Since the first linkage rod 43 and the second linkage rod 44 are both sleeved on the shaft 41 and synchronously drive them to rotate, the gripper 42 on the shaft 41 can synchronously clamp the substrate 6 and continue to lift. At this time, the lifting plate 35 on the driving cylinder 31 is against the bottom of the substrate platform 4 to lift it, which corresponds to the fixture for fixing the chip. After the fixture is released, the chip is placed on the substrate and the solder is placed for heating, and the lifting is continued. At this time, the substrate platform 4 is against the flange 51 on the guide rod 5 and cooperates with the contraction spring between the carrier 2 and the substrate platform 4 to form a regular shake to discharge the air, and finally the cleaning head 11 is adsorbed.

[0042] The substrate platform 4 is provided with a platform transverse groove 45 for the first linkage rod 43 and the second linkage rod 44 to pass through, and the platform cut groove 21 provided on the platform 2 is provided for the driving unit 3 to connect and cooperate with.

[0043] The base 1 is also provided with a moving cylinder 13 , which drives the cleaning head 11 to slide via a slide rail and a slider, and the cleaning head 11 is also connected with a vacuum tube 12 .

[0044] The cleaning head 11 includes three air inlet channels on both sides and a middle vacuum discharge channel separated by a partition inside. Ultrasonic oscillators are installed at the air inlet channels, and a conical adsorption channel is set at the vacuum discharge channel.

[0045] A cleaning method for a semiconductor package substrate cleaning device includes the following steps:

[0046] S1. Chip placement: First, an operator or automated equipment precisely places the chip at a predetermined position on the substrate, ensuring accurate alignment.

[0047] S2. Substrate fixation: Then, a gripper or fixture firmly fixes the substrate in place to prevent movement in subsequent steps.

[0048] S3. Substrate movement: Then, the substrate is controlled to move closer to the chip through an accurate drive system and placed on the chip, ensuring the relative position between the two is accurate.

[0049] S4. Solder application: Solder is applied between the chip and the substrate, usually by solder paste printing or pre-placing solder balls, to ensure uniform distribution of the solder.

[0050] S5. Heating: The substrate and the chip are heated to make the solder reach the melting point and melt into a liquid state to facilitate the formation of good solder joints.

[0051] S6. Slight shaking: When the solder is in a liquid state, the substrate platform 4 is continuously lifted by the driving cylinder 31 to abut against the flange 51 on the guide rod 5, and the substrate 6 is slightly shaken in cooperation with the contraction spring. The purpose of this is to help air bubbles escape from the solder and ensure good contact between the chip and the substrate.

[0052] S7. Cooling and curing: After the air bubbles escape, the substrate shaking is stopped, and the solder is allowed to cool and cure. The cured solder forms a solid solder joint, firmly fixing the chip on the substrate.

[0053] S8. Substrate cleaning: Finally, the cleaning head reciprocates through the cylinder, while generating ultrasonic oscillation to separate the fine particles on the substrate. The vacuum pump generates vacuum to exhaust the separated particles, ensuring the substrate surface is clean and pollution-free.

[0054] It should be noted that in this text, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variation thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the existence of additional identical elements in the process, method, article or device comprising the said element.

[0055] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A semiconductor packaging substrate cleaning device, comprising a base (1), a carrier stage (2), and a substrate platform (4), characterized in that: It includes a driving unit (3) and a clamping unit. The driving unit (3) drives the clamping unit to clamp the substrate (6) and drives the lifting and jitter of the substrate platform (4); The stacked platform (2) and the substrate platform (4) are directionally guided by the guide rods (5) connected to the platform (2). The lifting plate (35) connected to the driving unit (3) drives the substrate platform (4) to move up and down along the direction of the guide rods (5); The guide rods (5) are distributed at the corners of the platform (2). A number of flanges (51) connected to the relatively arranged guide rods (5) are staggered, and the flanges (51) are located in the upper middle part of the guide rods (5). A compression spring is also connected between the platform (2) and the substrate platform (4); It also includes a cleaning head (11) with ultrasonic oscillation that slides along the direction of the substrate (6) to ensure the cleanliness of the substrate.

2. The cleaning device for a semiconductor packaging substrate according to claim 1, wherein: The clamping unit includes a plurality of grippers (42) mounted on the rotating shaft (41). The same baffle is also connected between the grippers (42). The baffle surrounds the substrate (6) to prevent the solder from flowing out of the substrate (6).

3. The cleaning device for a semiconductor packaging substrate according to claim 1, wherein: The clamping unit also includes a first linkage rod (43) and a second linkage rod (44) connected to the rotating shaft (41). The first linkage rod (43) and the second linkage rod (44) are hinged.

4. A semiconductor package substrate cleaning device according to any one of claims 2-3, characterized in that: The driving unit (3) includes a driving cylinder (31). The output end of the driving cylinder (31) is provided with a driving rod (32). A pair of transmission rods (33) are hinged on the driving rod (32). The side end of the transmission rod (33) far from the driving rod (32) is connected with a connecting block (34) connected to the rotating shaft (41).

5. The cleaning device for a semiconductor packaging substrate according to claim 1, characterized in that: The substrate platform (4) is provided with a platform transverse groove (45) for the first linkage rod (43) and the second linkage rod (44) to pass through. The platform (2) is provided with a platform cutting groove (21) for the driving unit (3) to be connected and matched.

6. The cleaning device for a semiconductor packaging substrate according to claim 1, characterized in that: The base (1) is also provided with a moving cylinder (13). The moving cylinder (13) drives the cleaning head (11) to slide through a slide rail and slider, and a vacuum tube (12) is also connected to the cleaning head (11).

7. The cleaning device for a semiconductor packaging substrate according to claim 1, wherein: The cleaning head (11) includes two side air inlet channels and a middle vacuum discharge channel separated by a partition inside. Ultrasonic oscillators are arranged at the air inlet channels, and a conical adsorption channel is arranged at the vacuum discharge channel.

8. A cleaning method based on a cleaning device for a semiconductor packaging substrate: characterized in that, It includes the following steps: S1. Chip placement: First, the operator or automated equipment precisely places the chip at the predetermined position on the substrate to ensure accurate alignment; S2. Substrate fixation: Then, the gripper or fixture firmly fixes the substrate in place to prevent movement in subsequent steps; S3. Substrate movement: Then, through an accurate drive system, the substrate is controlled to approach the chip and placed on the chip to ensure the accurate relative position between the two; S4. Solder application: Solder is applied between the chip and the substrate, which is usually done by solder paste printing or pre-placing solder balls to ensure uniform distribution of the solder; S5. Heating: The substrate and the chip are heated to make the solder reach the melting point and melt into a liquid state to facilitate the formation of good solder joints; S6. Slight shaking: When the solder is in a liquid state, the substrate platform is continuously lifted by the driving cylinder so that it abuts against the flange on the guide rod, and the substrate is slightly shaken in cooperation with the contraction spring. The purpose of this is to help the bubbles escape from the solder and ensure good contact between the chip and the substrate; S7. Cooling and curing: After the bubbles escape, stop shaking the substrate and let the solder cool and cure. The cured solder forms a solid solder joint, firmly fixing the chip on the substrate; S8. Substrate cleaning: Finally, the cleaning head reciprocates through the cylinder, and at the same time generates ultrasonic oscillation to separate the fine particles on the substrate. The vacuum pump generates a vacuum to remove the separated particles, ensuring that the surface of the substrate is clean and pollution-free.

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