Cleaning and bearing device and cleaning method for thinned wafer

Abstract

The invention discloses a cleaning and bearing device and a cleaning method for thinned wafers. The invention relates to the technical field of chips, and discloses a thinned wafer cleaning and bearing device which comprises a lifting handle and a bearing part located at one end of the lifting handle, and the bearing part comprises a bearing body and a bearing clamping groove located in at least one side of the bearing body; the bearing clamping groove is arranged in an arc-shaped concave mode, the shape of the arc is matched with the shape of the wafer, and the bearing clamping groove is used for bearing the wafer during cleaning. The bearing clamping groove and the lifting handle are arranged in an inclined mode. When the thinned wafer is cleaned, the wafer is clamped in the groove through the bearing groove, and the groove wall of the bearing groove has a limiting effect, so that the movement and falling of the wafer are reduced, and the damage of the wafer is reduced. A certain included angle is formed between the bearing clamping groove and the vertical direction, cleaning dead angles can be eliminated, and the problem that cleaning liquid is not evenly distributed is solved.

Description

Technical Field

[0001] The present application relates to the field of chip technology, and in particular to a cleaning carrier device and a cleaning method for thinned wafers. Background Art

[0002] Wafer thinning is a key process in semiconductor chip manufacturing, aiming to reduce wafer thickness to meet the demands for miniaturization and higher performance. However, after wafer thinning, wafer removal and cleaning present numerous challenges.

[0003] Thinned wafers become thinner and more fragile, placing extremely high demands on cleaning effectiveness and wafer protection during the cleaning process. Incomplete cleaning can leave residual impurities and contaminants that can affect chip performance and reliability. Improper cleaning methods can also cause scratches, corrosion, and other damage to the wafer surface. Summary of the Invention

[0004] The present application provides a cleaning carrier device and a cleaning method for thinned wafers to solve the problems of improper cleaning and incomplete cleaning in related technologies.

[0005] In a first aspect, the present application provides a cleaning and carrying device for thinned wafers, comprising a handle and a carrying portion located at one end of the handle, wherein:

[0006] The carrying portion includes a carrying body and a carrying slot located on at least one side of the carrying body;

[0007] The carrying slot is arranged in an arc-shaped depression, the shape of the arc being adapted to the shape of the wafer, and is used to carry the wafer during cleaning;

[0008] The carrying card slot and the handle are arranged obliquely.

[0009] Ordinary wafers are thicker and have better mechanical properties. They can withstand certain external forces and their own gravity and are not easily deformed or damaged during the cleaning process. Therefore, they can be placed on a cleaning device similar to a plate rack. This cleaning device has a simple structure and can meet the support and fixation needs of ordinary wafers during the cleaning process. It is only necessary to ensure that there is an appropriate spacing between the wafers so that the cleaning liquid can fully contact the wafer surface. The mechanical properties of the thinned wafer deteriorate, and more sophisticated support and fixation methods are required to prevent damage due to uneven force, collision or shaking during the cleaning process. Usually, the thickness of ordinary wafer 300 is 350μm~750μm. InP wafers are brittle materials. The tensile stress itself is much greater than the shear stress, and the fracture energy is only 0.63J / m 2, the Kirkmar hardness is 537, and the thickness of the thinned wafer is 80μm~150μm. Due to the low hardness and reduced thickness, the fracture strength will be significantly reduced, and it is more likely that the wafer will be broken and scrapped due to fracture. This application can provide more stable and uniform support to ensure the safety and stability of the wafer during the cleaning process. The design of the cleaning carrier can enable the wafer to maintain a specific angle and position in the cleaning liquid to avoid collisions between wafers, and it is also conducive to better circulation of the cleaning liquid and flushing of the wafer surface.

[0010] The present application provides a carrier slot on at least one side of the carrier body, the carrier slot being an arc-shaped recessed arrangement, the arc shape being adapted to the shape of the wafer, and a carrier slot being provided along the extension direction of the arc for carrying the wafer. The carrier slot and the handle are arranged at an angle, so that when cleaning the thinned wafer, the wafer is clamped in the slot through the carrier slot, and the slot wall of the carrier slot has a limiting effect, reducing the movement and falling of the wafer and reducing damage to the wafer. The carrier slot and the handle are arranged at an angle, and under the action of gravity, the handle is usually placed in the cleaning tank in a direction perpendicular to the horizontal plane, that is, in a vertical direction. Therefore, the carrier slot is arranged at a certain angle to the vertical direction, which can eliminate cleaning dead corners and overcome the problem of uneven distribution of cleaning liquid, so that the cleanliness of the wafer fully meets the strict standards of semiconductor chip manufacturing. At the same time, this inclined design can also promote the downward precipitation of impurities such as wax and glue, preventing them from sticking back to the front of the wafer, thereby improving the cleaning quality. The wafer facing the carrier body is usually the back of the wafer, and the wafer facing away from the carrier body is the front of the wafer.

[0011] Tilt placement allows the cleaning fluid to flow better across the wafer surface under the action of gravity, improving cleaning fluid utilization and cleaning effectiveness. It also makes the wafer more stable in the cleaning carrier, reducing stress concentration caused by shaking or collisions during the cleaning process, protecting the thinned wafer from damage, and, to a certain extent, reducing the impact of the wafer's own gravity on it, reducing the risk of deformation caused by gravity. Tilt placement also makes the wafer more stable in the cleaning carrier, reducing stress concentration caused by shaking or collisions during the cleaning process, and reducing damage to the thinned wafer.

[0012] It should be noted that when cleaning the wafer, when it is placed vertically, the wafer is completely under its own weight. For thinned wafers, it is easy to be deformed by gravity, and may even cause the wafer to break. In addition, during the cleaning process, vertically placed wafers are more susceptible to the impact of the cleaning fluid and water flow fluctuations, further increasing the risk of wafer damage. After cleaning, the cleaning fluid on the surface of the vertically placed wafer in the traditional cleaning carrier drains slowly, and there will be more cleaning fluid residue, which not only affects the cleaning efficiency, but may also cause impurities in the cleaning fluid to adhere to the wafer surface again, affecting the quality of the wafer. At the same time, it is difficult for the operator to take the wafer at a vertical angle, and it is easy to cause the risk of wafer breakage due to the problem of the wafer taking angle.

[0013] It should be noted that the carrier body generally has four side surfaces, and a carrier slot is provided on at least one side of the carrier body. The carrier slot may be provided on only one side of the carrier body, on two opposite sides of the carrier body, or on all four sides of the carrier body. This application does not limit the shape of the carrier body, and the shape may be adjusted according to actual usage.

[0014] It should be noted that when the wafer is round, the shape of the clamping part is correspondingly round. When the shape of the wafer is an irregular structure, such as 1 / 4 or 1 / 2 piece, the clamping part can use any side of the clamping part to push the lower piece point to point, and the design can be widened and extended accordingly.

[0015] In some embodiments, the depth of the carrying card slot is 0.5 mm to 1 mm. Within this range, the carrying card slot can provide sufficient bearing capacity for the wafer, reduce the movement and damage of the wafer, and reduce the damage to the effective area of the wafer caused by contact with the wafer; and / or,

[0016] The width of the carrier slot is 0.05mm to 0.5mm. When the width of the carrier slot is within this range, the wafer support effect can be improved, while reducing the shaking of the wafer, reducing the friction when inserting and removing the wafer, and reducing the shaking and friction damage of the wafer.

[0017] In some embodiments, there is at least a partial hollow area between the carrier card slot and the carrier body for allowing the cleaning liquid to flow. The hollow area provides a circulation area for the cleaning liquid, facilitates cleaning of key locations, and improves the cleaning effect.

[0018] In some embodiments, the thickness of the hollowed-out area is 5 mm to 50 mm. When the thickness of the hollowed-out area is within this range, the cleaning liquid can flow more smoothly, improving the cleaning efficiency, reducing the residue of impurities, and enhancing the cleaning effect. It should be noted that the area of the hollowed-out area can be determined according to the effective area of the wafer. On the premise of ensuring reliable connection between the carrier slot and the carrier body, the area of the hollowed-out area can be made as large as possible to increase the water flow area, thereby enhancing the cleaning effect.

[0019] In some embodiments, a plurality of through holes are provided on the carrier body, and the diameter of the holes is 3 to 6 mm. By providing a plurality of through holes on the carrier body, the cleaning liquid can flow freely through the through holes, improving the cleaning effect. When the diameter of the holes is within this range, a certain cleaning water flow pressure can be provided, making the impurities on the wafer cleaner.

[0020] In some embodiments, the inclination angle between the carrier slot and the handle is 30° to 60°. When the inclination angle between the carrier slot and the handle is within this range, cleaning dead corners can be further eliminated, the problem of uneven distribution of the cleaning liquid can be overcome, making the cleanliness of the wafer fully meet the strict standards of semiconductor chip manufacturing. At the same time, it can also prompt impurities such as wax and glue to precipitate downward, preventing them from sticking back to the front side of the wafer and further improving the cleaning quality.

[0021] In a second aspect, the present application provides a cleaning method for a thinned wafer, including the following steps:

[0022] Using a wafer picking device for the thinned wafer to pick up the thinned wafer from the operating table;

[0023] Transferring the wafer to a cleaning carrier device for the thinned wafer as described in the first aspect for cleaning;

[0024] Among them, the wafer picking device for the thinned wafer includes a pusher and a wafer receiver. The pusher includes a pushing part, and the pushing part has an abutting surface that abuts against at least a part of the circumferential side wall of the wafer to be picked up, for pushing the wafer from the thinning carrier device;

[0025] The wafer receiver includes a receiving part, and the receiving part has a receiving groove for accommodating at least a part of the circumferential side wall of the wafer. When the pusher pushes the wafer to the edge of the thinning carrier device, it receives the wafer, fixes the wafer in the receiving groove, and transfers the wafer to the carrier slot of the cleaning carrier device for the thinned wafer;

[0026] The carrier slot is used to fix the wafer during cleaning.

[0027] The conventional thinning process is as follows: wax coating - melt the wax on the heating table, and use a tool to evenly apply it on the carrier substrate to form a wax film with a thickness of 0.01 to 0.03 mm. Wafer bonding - place the wafer face down on the wax-coated carrier substrate, eliminate bubbles, and ensure a tight fit. Curing - the thermoplastic wax cools naturally, and the thermosetting wax cures by heating. Thinning - install the assembly (wafer and carrier substrate combination) into the thinning equipment, set the parameters to start thinning, and monitor the thickness. Dewaxing - soak the assembly in the dewaxing solvent for 10 to 60 minutes, take it out and rinse with deionized water or cleaning solution.

[0028] During the dewaxing step, the wafers are transferred to the cleaning apparatus along with the wafer assembly. The support of the carrier substrate prevents the wafers from being damaged during transfer to the cleaning apparatus, despite being thinned. However, when the assembly is subsequently immersed in a solvent, the wafers are more likely to shake and break when they fall off the carrier substrate. This is especially true for thinned wafers, resulting in a low wafer yield.

[0029] The pushing portion of the wafer removal device for the thinned wafer has an abutment surface that abuts against at least part of the circumferential side wall of the wafer to be removed, and is used to push the wafer from the thinning carrier (the wax film is heated to soften the wax film before pushing), and the abutment surface is aligned with the arc edge of the wafer, pushing the wafer off the assembly in just a few seconds. Then, when the pusher pushes the wafer to the edge of the thinning carrier, the wafer is received by the splicer and fixed in the accommodating groove of the splicer, and the wafer is transferred to the carrying slot of the cleaning carrier of the thinned wafer through the splicer, so that the wafer is fixed in the carrying slot in the cleaning carrier of the first aspect and immersed in the dewaxing solvent for cleaning.

[0030] The pusher can abut against at least part of the side wall of the wafer through the abutment surface, and then push the wafer to move on the thinning carrier through the abutment surface, thereby avoiding damage to the wafer caused by placing the carrier and the wafer into the cleaning liquid together. Since the thinned wafer has low strength, is fragile and easily damaged, it is also easily damaged by the transport device during its separate transport. Therefore, the connecting portion has a accommodating groove for accommodating at least part of the circumferential side wall of the wafer. When the pusher pushes the wafer to the edge of the thinning carrier, the wafer is received and fixed in the accommodating groove, and the wafer is transferred to the supporting card slot of the cleaning carrier of the thinned wafer. The wafer can be transported by carding, reducing damage to the wafer during transportation. The cleaning carrier of the thinned wafer can make the wafer surface have an inclination angle with the horizontal plane, so that the wafer is completely immersed in the solution, the cleaning liquid is evenly covered, and the wax and glue are precipitated downward to avoid sticking back to the front side of the wafer. In addition, the cleaning carrier of the thinned wafer only contacts the outermost contour of the front or back side of the wafer in the area of the carrier groove wall, which can reduce the damage to the effective area caused by contact.

[0031] In some embodiments, the wafer pushing part is arranged in an arc shape, where:

[0032] The central angle of the arc of the wafer pushing part is 150 - 180°. The central angle of the arc of the wafer pushing part reflects the size of the contact area between the abutting surface of the wafer pushing part and the circumferential side wall of the wafer. When the central angle of the arc of the wafer pushing part is within this range, the contact area between the wafer pushing part and the wafer can be increased, so that the force is more evenly distributed when pushing the wafer, making it easier to push the wafer. At the same time, when cooperating with the chip bonding part, the interference of the chip bonding part can be reduced, facilitating docking; and / or,

[0033] The radius of the arc is R1, and the radius of the wafer is R2, 0.2mm ≤ R1 - R2 ≤ 0.5mm. When the difference in the radii of the wafer is within this range, the arc of the wafer pushing part can reduce the wobbling of the wafer in the wafer pusher during wafer pushing, and at the same time reduce the friction between the abutting surface and the circumferential side wall of the wafer, reducing wafer breakage; and / or,

[0034] Both ends of the arc are provided with rounded corners, and the radius of the rounded corner is R3, 3mm ≤ R3 ≤ 5mm. Providing rounded corners at both ends of the arc can reduce the damage to the wafer caused by both ends of the wafer pushing part, reducing the risk of wafer breakage; and / or,

[0035] The height of the wafer pushing part is H1, and the height of the wafer is H0, 0.05mm ≤ H1 - H0 ≤ 0.5mm. When the difference between the height of the wafer pushing part and the height of the wafer is within this range, the wafer can be pushed better, so that the contact surface of the entire circumferential side wall of the wafer with the wafer pushing part is lower than the abutting surface of the wafer pushing part, thereby protecting the side wall of the wafer and reducing damage to the wafer.

[0036] It should be noted that the wafer pusher further includes a holding body. The holding body can have the same thickness as the wafer pushing part and be arranged in a sheet shape, or it can have a different thickness from the wafer pushing part and be in a shape convenient for holding, such as the shape of a holding handle or a holding ring.

[0037] It should be noted that the material of the wafer pushing part can be at least one of FR4 and PTFE. These materials can not only provide a certain support strength to facilitate pushing the wafer, but also have a certain elasticity to reduce damage to the wafer. The material of the holding body can be the same as or different from the material of the wafer pushing part.

[0038] The groove wall of the receiving groove provides a limiting function for the wafer, preventing the wafer from falling during the wafer picking process, providing a stable gripping force for the transfer of the wafer, being able to ensure good contact with the wafer, and at the same time minimizing damage to the wafer, solving the problems of low efficiency in the traditional wafer picking method, easy wafer breakage and damage, and poor adaptability of the wafer picking tool, and greatly improving the wafer unloading speed and wafer picking efficiency.

[0039] In some embodiments, the accommodating groove includes a first groove wall and a second groove wall arranged in an arc shape, wherein the first groove wall abuts against the upper surface of the wafer, and the second groove wall abuts against the lower surface of the wafer, wherein:

[0040] The central angle of the first groove wall is 150° to 180°. The central angle of the first groove wall within this range facilitates wafer connection, does not interfere with the wafer pusher, reduces damage to the wafer, and provides sufficient supporting area for the wafer to reduce the risk of wafer falling; and / or,

[0041] The central angle of the second groove wall is 120° to 150°. When the central angle of the second groove wall is within this range, it can provide space when abutting against the edge of the wafer thinning carrier, making it easier for the wafer to enter the accommodating groove and improving the wafer splicing efficiency; and / or,

[0042] The thickness of the first groove wall is 2 mm to 3 mm. Within this range, the thickness of the first groove wall can provide sufficient strength for supporting the wafer; and / or,

[0043] The thickness of the second groove wall is 3 mm to 5 mm. Within this range, the thickness of the second groove wall can provide sufficient strength for supporting the wafer.

[0044] In some embodiments, the depth of the accommodating groove is 0.5 mm to 1 mm. The depth of the accommodating groove within this range can provide a sufficient accommodating depth for the wafer, thereby reducing the probability of the wafer falling during the transfer process; and / or,

[0045] The width of the receiving groove is 0.05 mm to 0.5 mm. When the width of the receiving groove is within this range, the shaking of the wafer in the receiving groove can be reduced, and the friction between the wafer and the receiving groove can be reduced, thereby reducing damage to the wafer.

[0046] It should be noted that the wafer splicer also includes a transfer portion. The transfer portion can be of the same thickness as the splicing portion and be in the form of a sheet, or it can be of a different thickness than the transfer portion and be shaped for easy gripping, such as a handle or a gripping ring. The splicing portion can be made of at least one of FR4 and PTFE. These materials provide both a certain degree of support strength to facilitate wafer handling and a certain degree of elasticity to reduce damage to the wafer. The transfer portion can be made of the same material as the splicing portion or a different material. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0048] Figure 1 Schematic diagram of the structure of a cleaning and carrying device for thinned wafers according to an embodiment of the present application.

[0049] Figure 2 This is a structural schematic diagram of a wafer pusher of a wafer removal device for a thinned wafer according to an embodiment of the present application.

[0050] Figure 3 This is a structural diagram of a wafer pusher of a wafer removal device for a thinned wafer according to an embodiment of the present application when pushing the wafer.

[0051] Figure 4 This is a structural schematic diagram of a wafer splicer of a wafer removal device for a thinned wafer according to an embodiment of the present application.

[0052] Figure 5 This is a structural schematic diagram of a wafer splicer of a wafer removal device for a thinned wafer according to an embodiment of the present application.

[0053] Figure 6 Schematic diagram of the structure of a device for removing a thinned wafer according to an embodiment of the present application.

[0054] Description of Figure Numbers:

[0055] 100 Wafer removal device for thinned wafers; 11 Wafer pusher; 111 Wafer pushing portion; 1111 Abutment surface; 112 Holding body; 12 Wafer connector; 121 Wafer connector portion; 1211 Accommodating groove; 12111 First groove wall; 12112 Second groove wall; 122 Transfer portion; 200 Cleaning and carrying device for thinned wafers; 21 Handle; 22 Carrying portion; 221 Carrying body; 2211 Hole; 222 Carrying slot; 300 Wafer. DETAILED DESCRIPTION

[0056] In order to enable those skilled in the art to better understand the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0057] Wafer thinning is a key process in semiconductor chip manufacturing, aiming to reduce wafer thickness to meet the demands of miniaturization and high performance. However, wafer removal and cleaning after thinning present numerous challenges.

[0058] Thinned wafers become thinner and more fragile, placing extremely high demands on cleaning effectiveness and wafer protection during the cleaning process. Incomplete cleaning can leave residual impurities and contaminants that can affect chip performance and reliability. Improper cleaning methods can also cause scratches, corrosion, and other damage to the wafer surface.

[0059] In view of this, the present application provides a cleaning carrier device and a cleaning method for thinned wafers to solve the problems of improper cleaning and incomplete cleaning in related technologies.

[0060] First, as Figure 1 As shown, the present application provides a cleaning and carrying device 200 for thinned wafers, comprising a handle 21 and a carrying portion 22 located at one end of the handle 21, wherein:

[0061] The carrying portion 22 includes a carrying body 221 and a carrying slot 222 located on at least one side of the carrying body 221;

[0062] The carrying slot 222 is configured as an arc-shaped depression, the shape of which matches the shape of the wafer 300, and is used to carry the wafer 300 during cleaning.

[0063] The carrying slot 222 and the handle 21 are arranged at an angle.

[0064] Ordinary wafers 300 are thicker and have better mechanical properties. They can withstand certain external forces and their own gravity and are not easily deformed or damaged during the cleaning process. Therefore, they can be placed on a cleaning device similar to a plate rack. This cleaning device has a simple structure and can meet the support and fixation requirements of ordinary wafers 300 during the cleaning process. It is only necessary to ensure that there is an appropriate spacing between the wafers 300 so that the cleaning liquid can fully contact the surface of the wafer 300. The mechanical properties of the thinned wafer deteriorate, and more sophisticated support and fixation methods are required to prevent damage due to uneven force, collision or shaking during the cleaning process. Usually, the thickness of ordinary wafers 300 is 350μm to 750μm. InP wafers are brittle materials. The tensile stress itself is much greater than the shear stress, and the fracture energy is only 0.63J / m 2, the Knoop hardness is 537, and the thickness of the thinned wafer is 80 μm to 150 μm. Due to the low hardness and reduced thickness, the fracture strength will be significantly reduced, and the wafer is more likely to be broken and scrapped due to fracture. This application can provide more stable and uniform support to ensure the safety and stability of the wafer 300 during the cleaning process. The design of the cleaning carrier device can keep the wafer 300 at a specific angle and position in the cleaning liquid, avoiding mutual collision between the wafers 300, and at the same time facilitating better circulation and flushing of the cleaning liquid on the surface of the wafer 300.

[0065] In this application, through the carrier slot 222 on at least one side of the carrier body 221, the carrier slot 222 is arranged as a circular arc-shaped depression, and the shape of the arc is adapted to the shape of the wafer 300. A carrier groove is provided along the extension direction of the arc for carrying the wafer 300. The carrier slot 222 is inclined with respect to the handle 21, so that when cleaning the thinned wafer, the wafer 300 is clamped in the groove through the carrier groove. The groove wall of the carrier groove has a limiting effect, reducing the movement and detachment of the wafer 300 and reducing the damage to the wafer 300. And the carrier slot 222 is inclined with respect to the handle 21. Under the action of gravity, the handle 21 is usually placed in the cleaning tank in a direction perpendicular to the horizontal plane, that is, the vertical direction. Therefore, the carrier slot 222 is arranged at a certain angle with respect to the vertical direction, which can eliminate the cleaning dead angle and overcome the problem of uneven distribution of the cleaning liquid, making the cleanliness of the wafer 300 fully meet the strict standards of semiconductor chip manufacturing. At the same time, this inclined design can also prompt impurities such as wax and glue to precipitate downward, avoiding their re-adhesion to the front surface of the wafer 300 and improving the cleaning quality. Usually, the wafer 300 facing the carrier body 221 is the back surface of the wafer 300, and the wafer 300 facing away from the carrier body 221 is the front surface of the wafer 300.

[0066] Inclined placement can make the cleaning liquid flow better through the surface of the wafer 300 under the action of gravity, improving the utilization rate and cleaning effect of the cleaning liquid. At the same time, inclined placement can also make the wafer 300 more stable in the cleaning carrier device, reducing the stress concentration caused by shaking or collision during the cleaning process, protecting the thinned wafer from damage, reducing the influence of the self-gravity of the wafer 300 to a certain extent, and reducing the deformation risk caused by gravity. At the same time, inclined placement can also make the wafer 300 more stable in the cleaning carrier device, reducing the stress concentration caused by shaking or collision during the cleaning process and reducing the damage to the thinned wafer.

[0067] It should be noted that when cleaning the wafer 300, when it is placed vertically, the wafer 300 is completely under its own weight. For the thinned wafer, it is easy to be deformed by the action of gravity, and may even cause the wafer 300 to break. In addition, during the cleaning process, the vertically placed wafer 300 is more susceptible to the impact of the cleaning liquid and the fluctuation of the water flow, further increasing the risk of damage to the wafer 300. After cleaning is completed, the cleaning liquid on the surface of the vertically placed wafer 300 in the traditional cleaning carrier is drained slowly, and there will be more cleaning liquid residue, which will not only affect the cleaning efficiency, but may also cause impurities in the cleaning liquid to adhere to the surface of the wafer 300 again, affecting the quality of the wafer 300. At the same time, it is difficult for the operator to take the wafer at a vertical angle, and it is easy to cause the risk of fragmentation due to the problem of the angle of taking the wafer.

[0068] It should be noted that the carrier body 221 generally has four side surfaces, and a carrier card slot 222 is provided on at least one side of the carrier body 221. The carrier card slot 222 may be provided on only one side of the carrier body 221, on two opposite sides of the carrier body 221, or on all four side surfaces of the carrier body 221. This application does not limit the shape of the carrier body 221, and the shape may be adjusted according to actual usage.

[0069] It should be noted that when the wafer 300 is circular, the shape of the clamping part is correspondingly circular. When the shape of the wafer 300 is an irregular structure, such as a 1 / 4 or 1 / 2 piece, the clamping part can use any side of the clamping part to push the lower piece point-to-point, and the design can be widened and extended accordingly.

[0070] In combination with the first aspect, in some embodiments provided in the present application, the depth of the supporting slot 222 is 0.5 mm to 1 mm. The depth of the supporting slot 222 is within this range, so that the supporting slot 222 can provide sufficient bearing force for the wafer 300, reduce the movement and damage of the wafer 300, and reduce the damage to the effective area of the wafer 300 caused by contact with the wafer 300.

[0071] In conjunction with the first aspect, in some embodiments provided herein, the width of the carrier slot 222 is 0.05 mm to 0.5 mm. Within this width range, the carrier slot 222 can improve the bearing effect on the wafer 300, while reducing the shaking of the wafer 300, reducing the friction during the insertion and removal of the wafer 300, and reducing the shaking and friction damage of the wafer 300.

[0072] In conjunction with the first aspect, in some embodiments provided herein, there is at least a partially hollowed area between the carrier slot 222 and the carrier body 221 for the flow of cleaning liquid. The hollowed area provides a circulation area for the cleaning liquid, facilitating cleaning of key locations and improving the cleaning effect.

[0073] In conjunction with the first aspect, in some embodiments provided in the present application, the thickness of the hollow area is 5 mm to 50 mm. The thickness of the hollow area within this range can make the cleaning liquid flow more smoothly, improve cleaning efficiency, reduce impurity residues, and enhance the cleaning effect. It should be noted that the area of the hollow area can be determined by the effective area of the wafer 300. Under the premise of ensuring that the carrying card slot 222 is reliably connected to the carrying body 221, the area of the hollow area can be made as large as possible to increase the water flow area, thereby improving the cleaning effect.

[0074] In conjunction with the first aspect, in some embodiments provided herein, the carrier body 221 is provided with a plurality of through holes 2211, each having a diameter of 3 to 6 mm. The plurality of through holes 2211 provided on the carrier body 221 allows the cleaning liquid to flow freely through the through holes 2211, thereby improving the cleaning effect. Within this range of diameters, the holes 2211 can provide a certain cleaning water pressure, thereby more thoroughly cleaning impurities from the wafer 300.

[0075] In conjunction with the first aspect, in some embodiments provided herein, the angle of inclination between the carrier slot 222 and the handle 21 is between 30° and 60°. Within this range, the angle of inclination between the carrier slot 222 and the handle 21 can further eliminate blind spots in cleaning and overcome the problem of uneven distribution of cleaning liquid, ensuring that the cleanliness of the wafer 300 fully meets the strict standards of semiconductor chip manufacturing. Furthermore, it can also encourage impurities such as wax and glue to settle downward, preventing them from adhering back to the front of the wafer 300, further improving cleaning quality.

[0076] In a second aspect, the present application provides a method for cleaning a thinned wafer, comprising the following steps:

[0077] The thinned wafer is removed from the operating table using the wafer removal device 100;

[0078] Transferring the wafer 300 to the cleaning carrier 200 for cleaning the thinned wafer as described in the first aspect;

[0079] Among them, such as Figure 2 and Figure 3As shown, the wafer picking device 100 for the thinned wafer includes a pusher 11 and a wafer receiver 12. The pusher 11 includes a pushing part 111, and the pushing part 111 has an abutting surface 1111 that abuts at least partially against the circumferential side wall of the wafer 300 to be picked, for pushing the wafer 300 from the thinning carrier device;

[0080] As Figure 4 and Figure 5 As shown, the wafer receiver 12 includes a receiving part 121, and the receiving part 121 has a receiving groove 1211 for accommodating at least partially the circumferential side wall of the wafer 300. When the pusher 11 pushes the wafer 300 to the edge of the thinning carrier device, it receives the wafer 300, fixes the wafer 300 in the receiving groove 1211, and transfers the wafer 300 to the receiving card slot 222 of the cleaning carrier device 200 for the thinned wafer;

[0081] The receiving card slot 222 is used to fix the wafer 300 during cleaning.

[0082] The conventional thinning process flow is as follows: wax coating - melting the sticky wax on the heating table and evenly coating it on the carrier substrate with a tool to form a wax film with a thickness of 0.01 - 0.03 mm. Wafer sticking - placing the wafer 300 face down on the wax-coated carrier substrate, removing air bubbles to ensure close fitting. Curing - natural cooling of the thermoplastic sticky wax, heating and curing of the thermosetting sticky wax. Thinning - loading the combination (wafer and carrier substrate combination) onto the thinning equipment, setting the parameters and starting thinning, and monitoring the thickness. Dewaxing - immersing the combination in a dewaxing solvent for 10 - 60 minutes, and after taking it out, rinsing it with deionized water or cleaning solution.

[0083] In the dewaxing step, the transfer of the wafer 300 is to put the combination of the wafer 300 into the cleaning device together. Due to the support of the carrier substrate, although the wafer 300 is thinned, it is not easily damaged during the transfer to the cleaning device. However, when the combination is put into the solvent together and the wafer falls off the carrier substrate, it is easy to cause the wafer 300 to shake and break, especially for the thinned wafer, resulting in a low qualified rate of the thinned wafer 300.

[0084] As Figures 2 to 6 shown, the pushing part 111 of the wafer picking device for the thinned wafer has an abutting surface 1111 that abuts at least partially against the circumferential side wall of the wafer 300 to be picked, for pushing the wafer 300 from the thinning carrier device. (Before pushing, heat the wax film to soften it), the abutting surface 1111 is aligned with the arc edge of the wafer 300, and the wafer 300 is pushed off from the combination, which only takes a few seconds. As Figure 6As shown, when the pusher 11 pushes the wafer 300 to the edge of the thinning carrier device, the wafer 300 is received by the bonding device 12, fixed in the receiving groove 1211 of the bonding device 12, and the wafer 300 is transferred to the receiving card slot 222 of the cleaning carrier device 200 of the thinned wafer through the bonding device 12, so that the wafer 300 is fixed in the receiving card slot 222 of the cleaning carrier device in the first aspect and soaked in the dewaxing solvent for cleaning.

[0085] The pusher 11 can abut against at least a part of the side wall of the wafer 300 through the abutting surface 1111, and then push the wafer 300 to move on the thinning carrier device through the abutting surface 1111, so as to avoid damaging the wafer 300 caused by putting the carrier device and the wafer 300 into the cleaning liquid together. Since the strength of the thinned wafer is low, it is fragile and easy to be damaged, and it is also easy to be damaged by the transfer device during its separate transfer. Therefore, the bonding part 121 has a receiving groove 1211 for receiving at least a part of the circumferential side wall of the wafer 300. When the pusher 11 pushes the wafer 300 to the edge of the thinning carrier device, the wafer 300 is received, fixed in the receiving groove 1211, and the wafer 300 is transferred to the receiving card slot 222 of the cleaning carrier device 200 of the thinned wafer. The wafer 300 can be transferred by a clamping method, reducing the damage of the wafer 300 during the transfer process. The cleaning carrier device 200 of the thinned wafer can make the surface of the wafer 300 have an inclined angle with the horizontal plane, so that the wafer 300 is completely immersed in the solution, the cleaning liquid is evenly covered, the wax and glue precipitate downward, avoiding sticking back to the front side of the wafer 300. Moreover, the cleaning carrier device 200 of the thinned wafer contacts only the area of the slot wall of the receiving slot with the outermost contour of the front or back side of the wafer 300, which can reduce the damage of the effective area caused by the contact.

[0086] Combined with the second aspect, in some embodiments provided by the present application, the pusher part 111 is arranged in an arc shape, wherein: the central angle of the arc of the pusher part 111 is 150-180°, and the central angle of the arc of the pusher part 111 reflects the size of the contact area between the abutting surface 1111 of the pusher part 111 and the circumferential side wall of the wafer 300. When the central angle of the arc of the pusher part 111 is within this range, the contact area between the pusher part 111 and the wafer 300 can be increased, so that the force is more uniform when pushing the wafer 300, and it is easier to push the wafer 300. At the same time, when cooperating with the bonding part 121, the interference of the bonding part 121 is reduced, which is convenient for docking.

[0087] In combination with the second aspect, in some embodiments provided by the present application, the pushing piece portion 111 is arranged in an arc shape, where: the radius of the arc is R1, the radius of the wafer 300 is R2, and 0.2 mm ≤ R1~R2 ≤ 0.5 mm. With the difference in the radii of the wafer 300 within this range, the arc of the pushing piece portion 111 can reduce the wobbling of the wafer 300 in the pusher 11 during pushing, while reducing the friction between the abutting surface 1111 and the circumferential side wall of the wafer 300, and reducing the breakage of the wafer 300.

[0088] In combination with the second aspect, in some embodiments provided by the present application, the pushing piece portion 111 is arranged in an arc shape, where: fillets are provided at both ends of the arc, and the radius of the fillet is R3, and 3 mm ≤ R3 ≤ 5 mm. Providing fillets at both ends of the arc can reduce the damage to the wafer 300 caused by both ends of the pushing piece portion 111, and reduce the risk of breakage of the wafer 300.

[0089] In combination with the second aspect, in some embodiments provided by the present application, the pushing piece portion 111 is arranged in an arc shape, where: the height of the pushing piece portion 111 is H1, the height of the wafer 300 is H0, and 0.05 mm ≤ H1 - H0 ≤ 0.5 mm. With the difference in the height of the pushing piece portion 111 and the height of the wafer 300 within this range, the wafer 300 can be better pushed, so that the contact surface of the entire circumferential side wall of the wafer 300 in contact with the pushing piece portion 111 is lower than the abutting surface 1111 of the pushing piece portion 111, thereby protecting the side wall of the wafer 300 and reducing the damage to the wafer 300.

[0090] It should be noted that the pusher 11 further includes a holding body 112. The holding body 112 can have the same thickness as the pushing piece portion 111 and be arranged in a sheet shape, or can have a different thickness from the pushing piece portion 111 and be in a shape convenient for holding, such as the shape of a holding handle or a holding ring.

[0091] It should be noted that the material of the pushing piece portion 111 can be at least one of FR4 and PTFE. These materials can not only provide a certain support strength to facilitate the pushing of the wafer 300, but also have a certain elasticity to reduce the damage to the wafer 300. The material of the holding body 112 can be the same as or different from the material of the pushing piece portion 111.

[0092] The groove wall of the receiving groove 1211 provides a limiting function for the wafer 300, preventing the wafer 300 from falling during the wafer picking process, providing a stable grasping force for the transfer of the wafer 300, being able to ensure good contact with the wafer 300, and minimizing the damage to the wafer 300 to the greatest extent. It solves the problems of low efficiency in the traditional wafer picking method, easy breakage and damage of the wafer 300, and poor adaptability of the wafer picking tool, and greatly improves the wafer unloading speed and wafer picking efficiency.

[0093] In combination with the second aspect, in some embodiments provided in the present application, the accommodating groove 1211 includes a first groove wall 12111 and a second groove wall 12112 arranged in an arc shape, wherein the first groove wall 12111 abuts the upper surface of the wafer 300, and the second groove wall 12112 abuts the lower surface of the wafer 300, wherein: the central angle of the first groove wall 12111 is 150° to 180°. The central angle of the first groove wall 12111 is within this range, which is convenient for connecting the wafers, does not interfere with the pusher 11, reduces damage to the wafer 300, and provides sufficient bearing area for the wafer 300, reducing the risk of the wafer 300 falling; and / or,

[0094] In combination with the second aspect, in some embodiments provided in the present application, the accommodating groove 1211 includes a first groove wall 12111 and a second groove wall 12112 arranged in an arc shape, wherein the first groove wall 12111 abuts the upper surface of the wafer 300, and the second groove wall 12112 abuts the lower surface of the wafer 300, wherein: the central angle of the second groove wall 12112 is 120°~150°. The central angle of the second groove wall 12112 is within this range, which can provide a clearance space when abutting the edge of the wafer 300 thinning carrier device, so that the wafer 300 can enter the accommodating groove 1211 more easily, thereby improving the efficiency of splicing.

[0095] In combination with the second aspect, in some embodiments provided in the present application, the accommodating groove 1211 includes a first groove wall 12111 and a second groove wall 12112 arranged in an arc shape, wherein the first groove wall 12111 abuts the upper surface of the wafer 300, and the second groove wall 12112 abuts the lower surface of the wafer 300, wherein: the thickness of the first groove wall 12111 is 2mm~3mm, and the thickness of the first groove wall 12111 within this range can provide sufficient strength for supporting the wafer 300.

[0096] In conjunction with the second aspect, in some embodiments provided herein, the accommodating groove 1211 includes a first groove wall 12111 and a second groove wall 12112 arranged in an arc shape, wherein the first groove wall 12111 abuts the upper surface of the wafer 300, and the second groove wall 12112 abuts the lower surface of the wafer 300. The thickness of the second groove wall 12112 is 3 mm to 5 mm. Within this thickness range, the second groove wall 12112 can provide sufficient strength for supporting the wafer 300.

[0097] In combination with the second aspect, in some embodiments provided in the present application, the depth of the accommodating groove 1211 is 0.5 mm to 1 mm. The depth of the accommodating groove 1211 is within this range, which can ensure that the wafer 300 has sufficient accommodating depth and reduce the probability of the wafer 300 falling during the transfer process of the wafer 300.

[0098] In conjunction with the second aspect, in some embodiments provided herein, the width of the receiving groove 1211 is 0.05 mm to 0.5 mm. The width of the receiving groove 1211 within this range can reduce shaking of the wafer 300 in the receiving groove 1211, while reducing friction between the wafer 300 and the receiving groove 1211, thereby reducing damage to the wafer 300.

[0099] It should be noted that the wafer splicer 12 also includes a transfer portion 122. The transfer portion 122 can be of the same thickness as the splicing portion 121 and be in a sheet-like configuration. Alternatively, the transfer portion 122 can be of a different thickness than the transfer portion 122 and be shaped for easy gripping, such as a handle or a gripping ring. The splicing portion 121 can be made of at least one of FR4 and PTFE. These materials provide both a certain degree of support strength to facilitate receiving the wafer 300 and a certain degree of elasticity to reduce damage to the wafer 300. The material of the transfer portion 122 can be the same as or different from that of the splicing portion 121.

[0100] In summary, the carrying slot on at least one side of the carrying body is arranged in an arc-shaped recessed configuration, the shape of the arc being adapted to the shape of the wafer, and a carrying slot is provided along the extension direction of the arc for carrying the wafer. The carrying slot and the handle are arranged at an angle, so that when cleaning the thinned wafer, the wafer is clamped in the slot through the carrying slot, and the slot wall of the carrying slot has a limiting effect, reducing the movement and falling of the wafer and reducing the damage to the wafer. Moreover, the carrying slot and the handle are arranged at an angle, and under the action of gravity, the handle is usually placed in the cleaning tank in a direction perpendicular to the horizontal plane, that is, in a vertical direction. Therefore, the carrying slot is arranged at a certain angle to the vertical direction, which can eliminate cleaning dead corners and overcome the problem of uneven distribution of the cleaning liquid, so that the cleanliness of the wafer fully meets the strict standards of semiconductor chip manufacturing. At the same time, this inclined design can also promote the downward precipitation of impurities such as wax and glue, preventing them from sticking back to the front of the wafer, thereby improving the cleaning quality.

[0101] In the description of this application, it should be noted that the terms "upper" and "lower" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application. Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be internal communication between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0102] It should be noted that in this application, 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 variant thereof is intended to cover non-exclusive inclusion, such 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 further 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 presence of additional identical elements in the process, method, article or device comprising the said element.

[0103] The above are only specific embodiments of the present application, enabling those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to these embodiments shown herein, but rather will be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A cleaning and loading device for a thinned wafer, characterized in that, It includes a handle and a bearing part located at one end of the handle, wherein: The bearing part includes a bearing body and bearing slots located on at least one side of the bearing body; The bearing slots are arranged as arc-shaped depressions, and the shape of the arc is adapted to the shape of the wafer for bearing the wafer during cleaning; The bearing slots are inclined with respect to the handle.

2. The cleaning and bearing device for a thinned wafer according to claim 1, wherein: The depth of the bearing slots is 0.5 mm to 1 mm; and / or, The width of the bearing slots is 0.05 mm to 0.5 mm.

3. The cleaning and carrying device for the thinned wafer as described in claim 1, characterized in that, There is at least a partially hollowed-out area between the bearing slots and the bearing body for the cleaning liquid to flow through.

4. The cleaning and loading device for the thinned wafer according to claim 3, characterized in that, The thickness of the hollowed-out area is 5 mm to 50 mm.

5. The cleaning and carrying device for the thinned wafer according to claim 3, wherein, A plurality of through holes are provided on the bearing body, and the diameter of the holes is 3 to 6 mm.

6. The cleaning and carrying device for the thinned wafer as described in claim 1, wherein, The inclination angle between the bearing slots and the handle is 30° to 60°.

7. A cleaning method for a thinned wafer, characterized in that, It includes the following steps: Use the wafer picking device for the thinned wafer to pick up the thinned wafer from the operating table; Transfer the wafer to the cleaning and bearing device for the thinned wafer according to any one of claims 1 to 6 for cleaning; Among them, the wafer picking device for the thinned wafer includes a pusher and a wafer receiver. The pusher includes a pushing part, and the pushing part has a contact surface that abuts against at least a part of the circumferential side wall of the wafer to be picked up, so as to push the wafer from the thinning and bearing device; The wafer receiver includes a receiving part. The receiving part has a receiving groove for accommodating at least a part of the circumferential side wall of the wafer. When the pusher pushes the wafer to the edge of the thinning and bearing device, it receives the wafer, fixes the wafer in the receiving groove, and transfers the wafer to the bearing slots of the cleaning and bearing device for the thinned wafer; The bearing slots are used to fix the wafer during cleaning.

8. The cleaning method of the thinned wafer according to claim 7, characterized in that, The pushing part is arranged in an arc shape, wherein: The central angle of the arc of the pushing part is 150° to 180°; and / or, The radius of the arc is R1, and the radius of the wafer is R2, 0.2 mm ≤ R1 - R2 ≤ 0.5 mm; and / or, Round corners are provided at both ends of the arc, and the radius of the round corners is R3, 3 mm ≤ R3 ≤ 5 mm; and / or, The height of the pushing part is H1, and the height of the wafer is H0, 0.05 mm ≤ H1 - H0 ≤ 0.5 mm.

9. The cleaning method of the thinned wafer as described in claim 7, characterized in that, The receiving groove includes a first groove wall and a second groove wall arranged in an arc shape. The first groove wall abuts against the upper surface of the wafer, and the second groove wall abuts against the lower surface of the wafer, wherein: The central angle of the first groove wall is 150° to 180°; and / or, The central angle of the second groove wall is 120° to 150°; and / or, The thickness of the first groove wall is 2 mm to 3 mm; and / or, The thickness of the second groove wall is 3 mm to 5 mm.

10. The cleaning method for a thinned wafer according to claim 7, wherein: The depth of the receiving groove is 0.5 mm to 1 mm; and / or, The width of the receiving groove is 0.05 mm to 0.5 mm.

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