Wafer carrier

Abstract

The invention provides a wafer carrier. The wafer carrier comprises a wafer tray, an annular piece, a driving device and a second suction cup assembly. The wafer tray comprises a bearing surface for bearing a wafer and an adsorption groove arranged on the bearing surface. A plurality of through holes are formed in the bearing surface, the through holes are uniformly distributed in at least two circumferences with different diameters, and suction cup assemblies capable of sliding up and down are arranged in the through holes. The annular piece is arranged below the wafer tray, a plurality of slope-shaped protrusions are arranged on the surface of the annular piece, and the bottom end of the suction cup assembly abuts against the surface of the annular piece all the time. The height of the top of the sucker assembly relative to the bearing face is adjusted by changing the abutting position of the bottom of the sucker assembly and the surface of the annular piece. The driving device is used for driving the annular piece to rotate so as to change the abutting position of the annular piece and the suction cup assembly. The wafer carrier provided by the invention can compatibly bear and adsorb wafers of multiple sizes.

Description

Technical Field

[0001] The present application relates to the field of semiconductor processing and manufacturing technology, and in particular to a wafer carrier that is compatible with multiple sizes. Background Art

[0002] During the inspection process of semiconductor wafers, a wafer tray is required to adsorb and fix the wafers, and to keep the surface of the wafers as flat as possible under the adsorption effect of the tray, so that the inspection system can handle these wafers normally.

[0003] First, because wafers come in different sizes, conventional technology typically requires a wafer tray of a specific size for each wafer size. This means that each wafer tray can only support and hold wafers of a specific size. Therefore, different trays must be replaced for wafers of different sizes, making the process cumbersome and inefficient.

[0004] Furthermore, due to the influence of upstream manufacturing processes, wafers reaching the inspection stage will have varying degrees of warpage. Furthermore, wafers of different sizes will have different warpage forms and amounts due to differences in material stress distribution.

[0005] Currently, during semiconductor wafer inspection, commonly used wafer trays rely on flat suction cups to hold wafers. However, this design is ineffective when holding warped wafers. Summary of the Invention

[0006] The purpose of this application is to provide a wafer carrier that is compatible with carrying and adsorbing wafers of multiple sizes.

[0007] The present application provides a wafer carrier, which includes a wafer tray, a ring, a driving device and a suction cup assembly.

[0008] The wafer tray includes a carrying surface for carrying wafers and an adsorption groove arranged on the carrying surface. A plurality of through holes are arranged on the carrying surface, and the plurality of through holes are evenly distributed on at least two circumferences of different diameters. A suction cup assembly that can slide up and down is arranged in the through holes. An annular member is arranged below the wafer tray, and a plurality of sloped protrusions are arranged on the surface of the annular member. The bottom end of the suction cup assembly is always in contact with the surface of the annular member; the height of the top of the suction cup assembly relative to the carrying surface is adjusted by changing the contact position between the bottom of the suction cup assembly and the surface of the annular member. The driving device is used to drive the annular member to rotate to change the contact position between the annular member and the suction cup assembly.

[0009] In one feasible solution, the through holes provided on the supporting surface of the wafer tray include a plurality of first through holes and a plurality of second through holes; the first through holes are evenly distributed along the first circumference, the second through holes are evenly distributed along the second circumference, the first circumference and the second circumference are concentric, and the diameter of the first circumference is smaller than the diameter of the second circumference. The annular member includes an inner ring and an outer ring connected to each other, the inner ring is below the first circumference, and the outer ring is below the second circumference; the upper surface of the inner ring is provided with a plurality of first sloped protrusions evenly distributed around the circumference, and the upper surface of the outer ring is provided with a plurality of second sloped protrusions evenly distributed around the circumference. The suction cup assembly includes a first suction cup assembly and a second suction cup assembly; the first suction cup assembly is slidably installed in the first through hole, and its bottom always remains in contact with the upper surface of the inner ring; the second suction cup assembly is slidably installed in the second through hole, and its bottom always remains in contact with the upper surface of the outer ring.

[0010] In an implementable solution, the number of first through holes is K1, and the number of second through holes is K2; wherein, K1 ≥ 3, K2 ≥ 3; the number of first sloped protrusions provided on the upper surface of the inner ring is N1, and the number of second sloped protrusions provided on the upper surface of the outer ring is N2; wherein, N1 = m1*K1, m1 is a positive integer; N2 = m2*K2, m2 is a positive integer.

[0011] In one feasible solution, the number of the first through holes is the same as that of the second through holes, i.e., K1=K2, and the first through holes and the second through holes are distributed in the same radial direction; the number of the first sloped protrusions is the same as that of the second sloped protrusions, i.e., N1=N2, and the first sloped protrusions and the second sloped protrusions are distributed in the same radial direction.

[0012] In an implementable solution, the upper surface of the inner ring is further provided with a plurality of gently sloping protrusions, which are the same in number as the first sloped protrusions and are evenly distributed circumferentially in the intervals between adjacent first sloped protrusions; the first suction cup assembly is a negative pressure suction cup assembly that can control adsorption or release; by making the bottom of the first suction cup assembly contact with at least part of the surface of the gently sloping protrusion, the top of the first suction cup assembly extends beyond the bearing surface of the wafer tray.

[0013] In an implementable solution, both ends of the gently sloping protrusion transition smoothly with the upper surface of the inner ring, and the surface of the gently sloping protrusion is configured to have a surface with varying heights.

[0014] In an implementable solution, the first suction cup assembly and the second suction cup assembly have the same length in the vertical direction, and the top end of the first sloped protrusion does not exceed the top end of the second sloped protrusion.

[0015] In one feasible solution, the top end of the first sloped protrusion is lower than the top end of the second sloped protrusion.

[0016] In an implementable solution, the height difference between the top of the first slope-shaped protrusion and the top of the second slope-shaped protrusion is 3 mm to 7 mm.

[0017] In an implementable solution, the first sloped protrusion and the second sloped protrusion are trapezoidal, with the short base at the top and the long base coinciding with the upper surfaces of the inner ring and the outer ring, and the two sides of the trapezoid are inclined.

[0018] In an implementable solution, a negative pressure air circuit is provided in the wafer tray body, the negative pressure air circuit is connected to the adsorption groove on the upper surface of the wafer tray, and a vacuum logic valve is provided at the connection point; the vacuum logic valve to which the wafer is attached is in an on state, and the vacuum logic valve to which the wafer is not attached is in a disconnected state.

[0019] In an implementable solution, the adsorption groove includes a plurality of concentrically distributed and mutually unconnected annular grooves, and each annular groove is connected to a negative pressure air path in the wafer tray body through a plurality of vacuum logic valves.

[0020] In an implementable solution, the wafer carrier further includes a tray base, an edge of the wafer tray is fixedly connected to the tray base, and a cavity for accommodating the annular member and the driving device is formed between the wafer tray and the tray base.

[0021] In an implementable scheme, the first suction cup assembly includes a first suction cup, a first suction cup push rod and a first return spring; the first suction cup push rod is slidably installed in the first through hole of the wafer tray, the first suction cup is installed at the top of the first suction cup push rod, the first return spring is sleeved on the first suction cup push rod, and the first return spring always gives the first suction cup push rod a downward force so that the bottom of the first suction cup push rod always contacts the upper surface of the inner ring; the second suction cup assembly includes a second suction cup, a second suction cup push rod and a second return spring; the second suction cup push rod is slidably installed in the second through hole of the wafer tray, the second suction cup is installed at the top of the second suction cup push rod, the second return spring is sleeved on the second suction cup push rod, and the second return spring always gives the second suction cup push rod a downward force so that the bottom of the second suction cup push rod always contacts the upper surface of the outer ring.

[0022] In an implementable scheme, the first suction cup assembly includes a first suction cup, a first suction cup push rod and a first return spring; the first suction cup push rod is slidably installed in the first through hole of the wafer tray, the first suction cup is installed on the top of the first suction cup push rod, the first return spring is sleeved on the first suction cup push rod, and the first return spring always applies a downward force to the first suction cup push rod so that the bottom of the first suction cup push rod always contacts the upper surface of the inner ring; wherein, the first suction cup is a negative pressure suction cup, and a negative pressure air duct connected to the first suction cup is arranged in the first suction cup push rod, and the negative pressure air duct is used to connect to an external negative pressure generating device.

[0023] Compared with the prior art, the beneficial effects of this application include at least:

[0024] First, the wafer carrier of the present application drives the ring part to rotate through a driving device, thereby changing the contact position between the ring part and the suction cup assembly, and using the sloped convex surface and the non-slope convex surface on the ring part to interfere with the bottom of the suction cup assembly, so as to raise or lower the suction cup assemblies on different circumferences, thereby being able to receive wafers of different sizes and place them on the surface of the wafer tray for adsorption and fixation. Therefore, the wafer carrier of the present application is compatible with the reception and adsorption of wafers of different sizes, making the wafer carrier more integrated, improving the versatility and production flexibility of the wafer carrier, and reducing production costs.

[0025] In a further solution, the ring member of the wafer carrier of the present application is further provided with a gently sloping protrusion that is different from the sloped protrusion. At the same time, some of the suction cup assemblies are controllable negative pressure suction cup assemblies. After the wafer is placed on the surface of the wafer tray, the driving device continues to drive the ring member to rotate so that the surface of the gently sloping protrusion collides with the bottom of some of the suction cup assemblies. Some of the suction cup assemblies are raised to exceed the bearing surface and adsorb the wafer through negative pressure. Then, they gradually leave the bottom of the suction cup assembly through the gently sloping protrusion to lower the suction cup assembly. Under the negative pressure adsorption and pulling of the suction cup assembly, the wafer is tightly attached to the tray surface, thereby solving the problem of weak adsorption of warped wafers and improving the smoothness of production and testing links. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0027] Figure 1 A three-dimensional diagram of a wafer carrier shown in an embodiment of the present application;

[0028] Figure 2 for Figure 1 A top view of the wafer carrier;

[0029] Figure 3 for Figure 1 Exploded diagram of the wafer carrier structure;

[0030] Figure 4 This is a structural diagram of a ring member compatible with multiple sizes shown in an embodiment of the present application;

[0031] Figure 5 for Figure 4 A front view of the inner ring section of the middle ring member;

[0032] Figure 6 This is a structural diagram of the negative pressure air circuit inside the wafer tray shown in an embodiment of the present application;

[0033] Figure 7 For the Figure 6 The cross-sectional view of the wafer carrier is taken along line AA in the middle;

[0034] Figure 8 This is a schematic diagram of the local structure of the first suction cup assembly in contact with the inner ring.

[0035] In the figure: 1. Wafer tray; 11. First through hole; 12. Second through hole; 101. Adsorption groove; 1011. Annular groove; 102. Negative pressure air path; 103. Vacuum logic valve; 104. Air path connector; 2. Ring member; 21. Inner ring; 211. First sloped protrusion; 212. Gentle slope protrusion; 22. Outer ring; 221. Second sloped protrusion; 3. Driving device; 4. First suction cup assembly; 41. First suction cup; 42. First suction cup push rod; 43. First return spring; 44. Negative pressure air path; 5. Second suction cup assembly; 6. Tray base. DETAILED DESCRIPTION

[0036] To make the objectives, technical solutions, and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Generally, the components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations.

[0037] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for protection, but merely represents selected embodiments of the present application. All other embodiments obtained by persons of ordinary skill in the art based on the embodiments in the present application without creative work are within the scope of protection of the present application.

[0038] like Figures 1 to 4 As shown, the application provides an embodiment of a wafer carrier, which at least includes a wafer tray 1, a suction cup assembly, a ring member 2 and a driving device.

[0039] The wafer tray 1 includes a carrying surface for carrying wafers and an adsorption groove 101 arranged on the carrying surface. A plurality of through holes are provided on the carrying surface, and the plurality of through holes are evenly distributed on at least two circumferences of different diameters. A suction cup assembly that can slide up and down is provided in the through holes. The ring member 2 is provided below the wafer tray 1, and a plurality of sloped protrusions are provided on the surface of the ring member 2. The bottom end of the suction cup assembly is always in contact with the surface of the ring member 2; the height of the top of the suction cup assembly relative to the carrying surface is adjusted by changing the contact position between the bottom of the suction cup assembly and the surface of the ring member 2. The driving device 3 is used to drive the ring member 2 to rotate to change the contact position between the ring member 2 and the suction cup assembly.

[0040] In addition, the wafer carrier may further include a tray base 6 , the edge of the wafer tray 1 is connected and fixed to the tray base 6 , and a cavity for accommodating the ring member 2 and the driving device 3 is formed between the wafer tray 1 and the tray base 6 .

[0041] In the wafer carrier of the present application, before receiving a wafer, the drive device 3 drives the ring member 2 to rotate, changing the contact position between the ring member 2 and the suction cup assembly. When at least a predetermined position of the sloped protrusion on the surface of the ring member 2 contacts the suction cup assembly, the top of the suction cup assembly extends beyond the surface of the wafer tray 1, preparing to receive the wafer. Because the support surface is provided with a plurality of through holes evenly distributed along at least two circumferences of different diameters, each through hole is provided with a suction cup assembly, the wafer can be placed on the suction cup assembly located on the corresponding circumference according to the size of the wafer. Thereafter, the drive device 3 drives the ring member 2 to continue rotating, changing the contact position between the ring member 2 and the suction cup assembly, gradually disengaging the sloped protrusion on the surface of the ring member 2 from the bottom of the suction cup assembly, causing the top of the suction cup assembly to gradually lower until it no longer extends beyond the surface of the wafer tray 1, thereby placing the wafer on the surface of the wafer tray 1 and then being adsorbed by the adsorption groove 101 on the surface of the wafer tray 1.

[0042] In summary, the wafer carrier of the present application drives the ring member 2 to rotate through the driving device 3, thereby changing the contact position between the ring member 2 and the suction cup assembly, thereby being able to raise or lower the suction cup assemblies on different circumferences, thereby being able to receive wafers of different sizes and place them on the surface of the wafer tray 1 for adsorption and fixation. Therefore, the wafer carrier of the present application is compatible with the reception and adsorption of wafers of different sizes, making the wafer carrier more integrated, improving the versatility and production flexibility of the wafer carrier, and reducing production costs.

[0043] In some embodiments, as Figures 1 to 4 As shown, the through-holes provided on the supporting surface of the wafer tray 1 may include a plurality of first through-holes 11 and a plurality of second through-holes 12; the first through-holes 11 are evenly distributed along a first circumference S1, and the second through-holes 12 are evenly distributed along a second circumference S2; the first circumference S1 and the second circumference S2 are concentric, and the diameter of the first circumference S1 is smaller than the diameter of the second circumference S2. The annular member 2 may include an inner ring 21 and an outer ring 22 connected to each other, with the inner ring 21 positioned below the first circumference S1 and the outer ring 22 positioned below the second circumference S2; the upper surface of the inner ring 21 is provided with a plurality of first sloped protrusions 211 evenly distributed around the circumference, and the upper surface of the outer ring 22 is provided with a plurality of second sloped protrusions 221 evenly distributed around the circumference. The suction cup assembly includes a first suction cup assembly 4 and a second suction cup assembly 5. The first suction cup assembly 4 is slidably installed in the first through hole 11, and its bottom is always kept in contact with the upper surface of the inner ring 21; the second suction cup assembly 5 is slidably installed in the second through hole 12, and its bottom is always kept in contact with the upper surface of the outer ring 22.

[0044] It should be noted that when the bottoms of the first suction cup assembly 4 and the second suction cup assembly 5 leave the corresponding sloped raised surfaces and come into contact with the horizontal surfaces of the inner ring 21 and the outer ring 22, the tops of the first suction cup assembly 4 and the second suction cup assembly 5 drop to a level that does not exceed the surface of the wafer tray 1.

[0045] In the wafer carrier of the present application, before receiving a wafer, the drive device 3 drives the ring member 2 to rotate so that a predetermined position on the surface of the first sloped protrusion 211 contacts the bottom of the first suction cup assembly 4, thereby causing the multiple first suction cup assemblies 4 to rise along the first through hole 11 and extend from the surface of the wafer tray 1. Similarly, the drive device 3 drives the ring member 2 to rotate so that a predetermined position on the surface of the second sloped protrusion 221 contacts the bottom of the second suction cup assembly 5, thereby causing the multiple second suction cup assemblies 5 to rise along the second through hole 12 and extend from the surface of the wafer tray 1. Because the multiple first through holes 11 are distributed along the first circumference S1 and the multiple second through holes 12 are distributed along the second circumference S2, and the diameter of the first circumference S1 is smaller than the diameter of the second circumference S2, the multiple first suction cup assemblies 4, after extending from the surface of the wafer tray 1, form a supporting area for relatively small wafers, and the multiple second suction cup assemblies 5, after extending from the surface of the wafer tray 1, form a supporting area for relatively large wafers.

[0046] After placing the wafer of corresponding size on the first suction cup assembly 4 or the second suction cup assembly 5, the driving device 3 drives the ring part 2 to continue to rotate, and then the first sloped protrusion 211 and / or the second sloped protrusion 221 gradually leave the bottom of the suction cup assembly, that is, the surface of the sloped protrusion gradually loses contact with the bottom of the suction cup assembly, and the suction cup assembly is lowered until the top of the suction cup assembly drops below the surface of the wafer tray 1, so as to place the wafer on the surface of the wafer tray 1, and then the adsorption groove 101 on the surface of the wafer tray 1 generates an adsorption force to adsorb the wafer.

[0047] In summary, the wafer carrier of the present application drives the ring part 2 to rotate through the driving device 3, thereby changing the position of the first sloped protrusion 211 on the inner ring 21 and / or the second sloped protrusion 221 on the outer ring 22, thereby causing the first suction cup assembly 4 and / or the second suction cup assembly 5 to rise and fall, forming bearing areas of different sizes, thereby being able to receive and adsorb wafers of multiple sizes, making the wafer carrier more integrated, compatible with wafers of different sizes, improving the versatility and production flexibility of the wafer carrier, and reducing production costs.

[0048] In some embodiments, the number of first through holes 11 is K1, and the number of second through holes is K2; where K1 ≥ 3 and K2 ≥ 3. The number of first sloped protrusions 211 provided on the upper surface of the inner ring 21 is N1, and the number of second sloped protrusions 221 provided on the upper surface of the outer ring 22 is N2. Where N1 = m1 * K1, where m1 is a positive integer; N2 = m2 * K2, where m2 is a positive integer.

[0049] In some embodiments, the first through hole 11 can be distributed in a different radial direction from the first through hole 11. At the same time, the corresponding second sloped protrusion 221 on the outer ring 22 and the first sloped protrusion 211 on the inner ring 21 are not in the same radial direction. Therefore, when the ring member 2 is driven to rotate by the driving device 3, the first suction cup assembly 4 and the second suction cup assembly 5 can be alternately raised or lowered.

[0050] However, in some preferred embodiments, as Figures 1 to 4 As shown, the number of the first through holes 11 and the second through holes 12 is the same, that is, K1=K2, and the first through holes 11 and the second through holes 12 are distributed in the same radial direction. The number of the first sloped protrusions 211 and the second sloped protrusions 221 is the same, that is, N1=N2, and the first sloped protrusions 211 and the second sloped protrusions 221 are distributed in the same radial direction. In addition, during the lifting and lowering process of the first suction cup assembly 4 and the second suction cup assembly 5, the top height of the first suction cup assembly 4 does not exceed the top height of the second suction cup assembly 5, thereby ensuring that when the second suction cup assembly 5 carries a relatively large wafer, the first suction cup assembly 4 will not lift the wafer to produce a reaction.

[0051] In some embodiments, as Figure 3 and Figure 4 As shown, the first suction cup assembly 4 and the second suction cup assembly 5 have the same vertical length, and the top of the first sloped protrusion 211 does not extend beyond the top of the second sloped protrusion 221, thereby ensuring that the top height of the first suction cup assembly 4 does not exceed the top height of the second suction cup assembly 5. Preferably, the top of the first sloped protrusion 211 is lower than the top of the second sloped protrusion 221. Specifically, the height difference between the top of the first sloped protrusion 211 and the top of the second sloped protrusion 221 is 3 mm to 7 mm, for example, 4 mm, 5 mm, 6 mm, etc.

[0052] In some embodiments, as Figure 4 and Figure 5 As shown, the first sloped protrusion 211 and the second sloped protrusion 221 are both trapezoidal, with the short base at the top and the long base coinciding with the upper surface of the inner ring 21 and the outer ring 22. Both sides of the trapezoid are inclined, so that the driving device 3 drives the ring member 2 to rotate counterclockwise or clockwise, and the sloped protrusion can drive the suction cup assembly to rise and fall.

[0053] In some embodiments, as Figure 8As shown, the first suction cup assembly 4 includes a first suction cup 41, a first suction cup top rod 42 and a first return spring 43. The first suction cup top rod 42 is slidably installed in the first through hole 11 of the wafer tray 1. The first suction cup 41 is installed at the top of the first suction cup top rod 42. The first return spring 43 is sleeved on the first suction cup top rod 42, and the first return spring 43 always gives the first suction cup top rod 42 a downward force so that the bottom of the first suction cup top rod 42 always contacts the upper surface of the inner ring 21. The second suction cup assembly 5 includes a second suction cup, a second suction cup top rod and a second return spring (not shown in the figure). The second suction cup top rod is slidably installed in the second through hole 12 of the wafer tray 1. The second suction cup is installed at the top of the second suction cup top rod. The second return spring is sleeved on the second suction cup top rod, and the second return spring always gives the second suction cup top rod a downward force so that the bottom of the second suction cup top rod always contacts the upper surface of the outer ring 22. It is understandable that according to the above scheme, the heights of the first slope protrusion 211 and the second slope 221 are set. When the first suction cup assembly 4 and the second suction cup assembly 5 move to the highest point respectively, the first suction cup is located higher than the second suction cup.

[0054] In the prior art, due to the influence of the upstream manufacturing process, the wafers that actually reach the detection process link will have different degrees of warping. In addition, wafers of different sizes have different warping shapes and warping amounts due to differences in material stress distribution. For wafers with larger warping, if a conventional wafer tray is used for adsorption and carrying, the vacuum leakage caused by the warping will cause the wafer to be unable to be firmly adsorbed on the wafer tray, thereby causing subsequent production and testing links to be unable to proceed smoothly. In order to solve this problem, based on the solution that the first through hole 11 and the first through hole 11 are distributed in the same radial direction, and the second sloped protrusion 221 on the outer ring 22 and the first sloped protrusion 211 on the inner ring 21 are also in the same radial direction, the present application further provides the following embodiments.

[0055] In some preferred embodiments, Figure 4 and Figure 5 As shown, the upper surface of the inner ring 21 is also provided with a plurality of gently sloping protrusions 212, which are the same in number as the first sloped protrusions 211 and are evenly distributed in the intervals between adjacent first sloped protrusions 211. The first suction cup assembly 4 is a negative pressure suction cup assembly that can control adsorption or release. By making the bottom of the first suction cup assembly 4 collide with at least part of the surface of the gently sloping protrusion 212, the top of the first suction cup assembly 4 exceeds the bearing surface of the wafer tray 1. Furthermore, when the bottom of the first suction cup assembly 4 collide with the surface of the gently sloping protrusion 212, the top of the second suction cup assembly 5 does not exceed the bearing surface of the wafer tray 1. When the bottom of the first suction cup assembly 4 collide with a predetermined position on the surface of the gently sloping protrusion 212 (for example, the highest point of the gently sloping protrusion 212), the top of the first suction cup assembly 4 exceeds the surface of the wafer tray 1, and at this time, the top of the first suction cup assembly 4 adsorbs the wafer. For example, as Figure 8 As shown, the first suction cup 41 of the first suction cup assembly 4 is a negative pressure suction cup, and a negative pressure airway 44 communicating with the first suction cup 41 is provided in the first suction cup top rod 42 , and the negative pressure airway 44 is used to communicate with an external negative pressure generating device.

[0056] Specifically, before receiving the wafer, the driving device 3 drives the ring part 2 to rotate, so that the first sloped protrusion 211 rotates to the bottom of the first suction cup assembly 4, and because the second sloped protrusion 221 is in the same radial direction as the first sloped protrusion 211, the second sloped protrusion 221 also rotates to the bottom of the second suction cup assembly 5, thereby causing the first suction cup assembly 4 and the second suction cup assembly 5 to gradually rise until they extend out of the surface of the wafer tray 1, and the top of the first suction cup assembly 4 does not exceed the top of the second suction cup assembly 5, and is ready to receive the wafer.

[0057] Then, wafers are placed on the first suction cup assemblies 4 or the second suction cup assemblies 5 according to their sizes. The drive device 3 then rotates the ring member 2, causing the first sloped protrusions 211 to gradually disengage from the bottom of the first suction cup assemblies 4, and the second sloped protrusions 221 to gradually disengage from the bottom of the second suction cup assemblies 5. As a result, the first and second suction cup assemblies 4 and 5 gradually descend until they are below the surface of the wafer tray 1, thereby placing the wafers on the surface of the wafer tray 1.

[0058] Next, the driving device 3 drives the ring member 2 to continue rotating so that the gently sloping protrusion 212 rotates to the bottom of the first suction cup assembly 4. The surface of the gently sloping protrusion 212 contacts the bottom of the first suction cup assembly 4, thereby causing the first suction cup assembly 4 to rise a certain distance and protrude from the surface of the wafer tray 1. At this time, the top of the first suction cup assembly 4 contacts the wafer, and the first suction cup assembly 4 adsorbs the wafer through the action of negative pressure. Then, the driving device 3 drives the ring member 2 to continue rotating so that the gently sloping protrusion 212 gradually disengages from the conflict with the bottom of the first suction cup assembly 4, thereby causing the first suction cup assembly 4 to gradually descend until it does not exceed the surface of the wafer tray 1. Since the first suction cup assembly 4 has negative pressure adsorption capacity, through the cooperation of the gently sloping protrusion 212, the first suction cup assembly 4 can be raised alone and adsorb the wafer, and then the wafer can be pulled down together until the wafer is tightly fitted with the surface of the wafer tray 1. Under the pulling force of the suction cup, even a warped wafer can form good contact with the surface of the wafer tray 1 , and then due to the action of the adsorption grooves 101 on the surface of the wafer tray 1 , the wafer can be firmly adsorbed on the wafer tray 1 .

[0059] In summary, the present application further provides a circumferentially evenly distributed gentle slope protrusion 212 on the upper surface of the inner ring 21, and the first suction cup assembly 4 is a controllable negative pressure suction cup assembly. The driving device 3 drives the annular member 2 to rotate, so that the first and second sloped protrusions leave the bottom of the suction cup assembly, and the suction cup assembly descends. After the wafer is placed on the surface of the wafer tray 1, the driving device 3 continues to rotate so that the gentle slope protrusion 212 reaches the bottom of the first suction cup assembly 4. The first suction cup assembly 4 rises and opens the negative pressure to adsorb the wafer, and then descends by leaving the bottom of the first suction cup assembly 4 through the gentle slope protrusion 212, thereby making the wafer fit tightly with the surface of the wafer tray 1. The wafer is adsorbed by negative pressure, solving the problem of weak adsorption of warped wafers and improving the smoothness of production and testing links.

[0060] In some embodiments, as Figure 5 As shown, the two ends of the gently sloping protrusion 212 smoothly transition with the upper surface of the inner ring 21, and the surface of the gently sloping protrusion 212 is configured to have a varying height. For example, the gently sloping protrusion 212 can be a straight inclined surface, or a wavy surface with varying lift heights. Depending on the degree of wafer warpage, the gently sloping protrusion 212 can be rotated to different positions on the bottom of the first suction cup assembly 4, thereby enabling the first suction cup assembly 4 to have different lift heights.

[0061] In some embodiments, as Figure 5 As shown, the maximum height of the gently sloping protrusion 212 is lower than the maximum height of the first slope-shaped protrusion 211 .

[0062] In some embodiments, the surface height variations of all the gently sloping protrusions 212 may be exactly the same, or at least two of all the gently sloping protrusions 212 may have surfaces with different height variations, thereby enabling the multiple first suction cup assemblies 4 to exhibit different height differences as the gently sloping protrusions 212 are raised, thereby adapting to more complex wafer warping conditions.

[0063] In some embodiments, as Figure 6 and Figure 7 As shown, a negative pressure gas circuit 102 is provided in the wafer tray 1 body. This circuit is connected to an external negative pressure generating and controlling device via a gas circuit connector 104 provided on one side of the wafer tray 1. This circuit communicates with the adsorption groove 101 on the upper surface of the wafer tray 1, with a vacuum logic valve 103 provided at the connection point. The vacuum logic valve 103 is in the on state when a wafer is attached, and in the off state when no wafer is attached.

[0064] In some embodiments, as Figure 6 and Figure 7As shown, the adsorption groove 101 can include multiple concentrically distributed and disconnected annular grooves 1011. Each annular groove 1011 is connected to the negative pressure gas path 102 in the wafer tray 1 body via a plurality of vacuum logic valves 103. Only one negative pressure gas path 102 is required, allowing the wafer carrier to adsorb wafers of different sizes with only one negative pressure gas path 102, reducing the number of gas path connections, making the structure more compact, and improving compatibility.

[0065] For example, when adsorbing a relatively small wafer (150mm, 200mm in diameter, etc.), the edge of the wafer only covers the inner annular grooves 1011. The vacuum logic valves 103 in these annular grooves 1011 are open, generating a negative pressure adsorption force. The outer annular grooves 1011 are uncovered, and the vacuum logic valves 103 therein remain closed.

[0066] For another example, when adsorbing a relatively large wafer (such as 300 mm in diameter), the edge of the wafer covers all the annular grooves 1011 , and the vacuum logic valves 103 in these annular grooves 1011 are turned on to generate negative pressure adsorption force to adsorb the wafer.

[0067] The foregoing description is merely a partial list of preferred embodiments of the present application and is not intended to limit the present application. Persons skilled in the art will readily appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A wafer carrier, characterized in that: include: A wafer tray (1) comprises a carrying surface for carrying wafers and an adsorption groove (101) arranged on the carrying surface; a plurality of through holes are arranged on the carrying surface, the plurality of through holes are evenly distributed on at least two circumferences of different diameters, and a suction cup assembly that can slide up and down is arranged in the through holes; An annular member (2) is arranged below the wafer tray (1), and a plurality of sloped protrusions are provided on the surface of the annular member (2), so that the bottom end of the suction cup assembly always contacts the surface of the annular member (2); and the height of the top end of the suction cup assembly relative to the bearing surface is adjusted by changing the contact position between the bottom end of the suction cup assembly and the surface of the annular member (2); The driving device (3) is used for driving the annular member (2) to rotate so as to change the contact position between the annular member (2) and the suction cup assembly.

2. The wafer carrier according to claim 1, wherein: The through holes provided on the bearing surface of the wafer tray (1) include a plurality of first through holes (11) and a plurality of second through holes (12); the first through holes (11) are evenly distributed along a first circumference, the second through holes (12) are evenly distributed along a second circumference, the first circumference and the second circumference are concentric, and the diameter of the first circumference is smaller than the diameter of the second circumference; The annular member (2) comprises an inner ring (21) and an outer ring (22) connected to each other, wherein the inner ring (21) is located below the first circumference, and the outer ring (22) is located below the second circumference; a plurality of first sloped protrusions (211) uniformly distributed around the circumference are provided on the upper surface of the inner ring (21), and a plurality of second sloped protrusions (221) uniformly distributed around the circumference are provided on the upper surface of the outer ring (22); The suction cup assembly comprises a first suction cup assembly (4) and a second suction cup assembly (5); The first suction cup assembly (4) is slidably mounted in the first through hole (11), and its bottom is always kept in contact with the upper surface of the inner ring (21); the second suction cup assembly (5) is slidably mounted in the second through hole (12), and its bottom is always kept in contact with the upper surface of the outer ring (22).

3. The wafer carrier according to claim 2, wherein: The number of the first through holes (11) is K1, and the number of the second through holes is K2; wherein K1 ≥ 3, K2 ≥ 3; The number of the first slope-shaped protrusions (211) provided on the upper surface of the inner ring (21) is N1, and the number of the second slope-shaped protrusions (221) provided on the upper surface of the outer ring (22) is N2; Among them, N1=m1*K1, m1 is a positive integer; N2=m2*K2, m2 is a positive integer.

4. The wafer carrier according to claim 3, wherein: The number of the first through holes (11) and the second through holes (12) are the same, that is, K1=K2, and the first through holes (11) and the second through holes (12) are distributed in the same radial direction; The number of the first slope-shaped protrusions (211) and the second slope-shaped protrusions (221) is the same, that is, N1=N2, and the first slope-shaped protrusions (211) and the second slope-shaped protrusions (221) are distributed in the same radial direction.

5. The wafer carrier according to claim 4, wherein: The upper surface of the inner ring (21) is further provided with a plurality of gently sloping protrusions (212), which are the same in number as the first slope-shaped protrusions (211) and are evenly distributed in the intervals between adjacent first slope-shaped protrusions (211); The first suction cup assembly (4) is a negative pressure suction cup assembly capable of controlling adsorption or release; By making the bottom of the first suction cup assembly (4) contact at least a portion of the surface of the gently sloping protrusion (212), the top of the first suction cup assembly (4) is made to extend beyond the bearing surface of the wafer tray (1).

6. The wafer carrier according to claim 5, wherein: Both ends of the gently sloping protrusion (212) transition smoothly with the upper surface of the inner ring (21), and the surface of the gently sloping protrusion (212) is configured to have a surface with varying heights.

7. The wafer carrier according to any one of claims 2 to 6, characterized in that: The first suction cup assembly (4) and the second suction cup assembly (5) have the same length in the vertical direction, and the top end of the first sloped protrusion (211) does not exceed the top end of the second sloped protrusion (221).

8. The wafer carrier according to claim 7, wherein: The top of the first slope-shaped protrusion (211) is lower than the top of the second slope-shaped protrusion (221).

9. The wafer carrier according to claim 8, wherein: The height difference between the top of the first slope-shaped protrusion (211) and the top of the second slope-shaped protrusion (221) is 3 mm to 7 mm.

10. The wafer carrier according to any one of claims 2 to 6, characterized in that: The first sloped protrusion (211) and the second sloped protrusion (221) are trapezoidal, with the short base at the top and the long base coinciding with the upper surfaces of the inner ring (21) and the outer ring (22), and the two sides of the trapezoid are inclined.

11. The wafer carrier according to any one of claims 1 to 6, characterized in that: A negative pressure air path (102) is provided in the wafer tray (1) body, the negative pressure air path (102) is connected to the adsorption groove (101) on the upper surface of the wafer tray (1), and a vacuum logic valve (103) is provided at the connection point; The vacuum logic valve (103) to which the wafer is attached is in an on state, and the vacuum logic valve (103) to which the wafer is not attached is in an off state.

12. The wafer carrier according to claim 11, wherein: The adsorption groove (101) comprises a plurality of concentrically distributed and mutually unconnected annular grooves (1011), and each of the annular grooves (1011) is connected to the negative pressure air path (102) in the wafer tray (1) body via a plurality of vacuum logic valves (103).

13. The wafer carrier according to claim 1, wherein: It also includes a tray base (6), the edge of the wafer tray (1) is connected and fixed to the tray base (6), and a cavity for accommodating the annular member (2) and the driving device (3) is formed between the wafer tray (1) and the tray base (6).

14. The wafer carrier according to claim 2, wherein: The first suction cup assembly (4) comprises a first suction cup (41), a first suction cup top rod (42) and a first return spring (43); The first suction cup push rod (42) is slidably mounted in the first through hole (11) of the wafer tray (1), the first suction cup (41) is mounted on the top of the first suction cup push rod (42), the first return spring (43) is sleeved on the first suction cup push rod (42), and the first return spring (43) always applies a downward force to the first suction cup push rod (42), so that the bottom of the first suction cup push rod (42) always contacts the upper surface of the inner ring (21); The second suction cup assembly (5) comprises a second suction cup, a second suction cup top rod and a second return spring; The second suction cup push rod is slidably installed in the second through hole (12) of the wafer tray (1), the second suction cup is installed on the top of the second suction cup push rod, the second return spring is sleeved on the second suction cup push rod, and the second return spring always applies a downward force to the second suction cup push rod so that the bottom of the second suction cup push rod always contacts the upper surface of the outer ring (22).

15. The wafer carrier according to claim 5, wherein: The first suction cup assembly (4) comprises a first suction cup (41), a first suction cup top rod (42) and a first return spring (43); The first suction cup push rod (42) is slidably mounted in the first through hole (11) of the wafer tray (1), the first suction cup (41) is mounted on the top of the first suction cup push rod (42), the first return spring (43) is sleeved on the first suction cup push rod (42), and the first return spring (43) always applies a downward force to the first suction cup push rod (42), so that the bottom of the first suction cup push rod (42) always contacts the upper surface of the inner ring (21); The first suction cup (41) is a negative pressure suction cup, and a negative pressure airway (44) communicating with the first suction cup (41) is provided in the first suction cup top rod (42), and the negative pressure airway (44) is used to communicate with an external negative pressure generating device.

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