A cassette capable of accommodating wafers of different sizes and a cassette turning device

Abstract

The present application belongs to the technical field of wafer soaking process, and particularly relates to a wafer box capable of containing wafers of multiple sizes. The wafer box comprises two groups of side plates and a plurality of wafer fixing assemblies arranged between the two groups of side plates in a circumferential manner. First wafer fixing grooves and second wafer fixing grooves with different depths are formed on each wafer fixing assembly, and wafers of different sizes are respectively supported by the first wafer fixing grooves and the second wafer fixing grooves. Each wafer fixing assembly comprises a main body support rod, a plurality of protrusions are linearly and equidistantly arranged on the main body support rod, the first wafer fixing grooves are formed on the end faces of the protrusions, and the second wafer fixing grooves are formed between two protrusions, and the depth of the second wafer fixing grooves is greater than the depth of the first wafer fixing grooves. The wafer box is provided with a plurality of wafer fixing assemblies between the two groups of side plates to contain wafers of multiple sizes, and the wafer box has the advantages of simple structure, convenient preparation, low cost, adjustable space saving, and the like.

Description

Technical Field

[0001] This invention belongs to the field of wafer immersion process technology, and specifically relates to a wafer cassette and wafer cassette flipping device that can accommodate wafers of multiple sizes. Background Technology

[0002] Silicon wafers, also known as silicon ingots, are made from silicon ingots. Through specialized processes, millions of transistors can be etched onto silicon wafers, making them widely used in integrated circuit manufacturing. Currently, the manufacturing process for semiconductor devices and integrated circuits generally involves completing the front-side wafer processing first, followed by the back-side processing. Taking insulated-gate bipolar transistors (IGBTs) as an example, the front-side wafer processing typically includes front-side photolithography, front-side etching, front-side ion implantation, front-side annealing, front-side oxidation, and front-side deposition. The back-side wafer processing typically includes front-side film deposition, back-side thinning, cleaning, film removal, back-side ion implantation, back-side annealing, and back-side metallization. In these different processes, depending on the processing steps and equipment, sometimes the front side of the wafer needs to be used as the processing surface, and sometimes the back side needs to be used. Therefore, the orientation of the front and back sides of the wafer must be reversed. Even in the same wafer face processing technology, some processing equipment requires the front side of the wafer to face the wafer stage, while other processing equipment requires the back side of the wafer to face the wafer stage. Existing wafer cassettes have complex shapes, are difficult to manufacture, and have high costs. The number of wafers that a wafer cassette can hold is limited by the length of the wafer cassette, and each wafer cassette can only hold wafers of the same size, which further increases the cost and time of chip fabrication. Summary of the Invention

[0003] To address the aforementioned problems, the present invention aims to provide a wafer cassette capable of accommodating wafers of multiple sizes, thereby solving the problems of complex wafer cassette shapes, difficult manufacturing processes, high costs, limited wafer capacity due to the length of the wafer cassette, and the fact that each wafer cassette can only accommodate wafers of the same size, which further increases the cost and time of chip fabrication.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] An embodiment of the present invention provides a wafer cassette capable of accommodating wafers of multiple sizes, including two sets of side plates and a plurality of wafer fixing components disposed between the two sets of side plates and distributed circumferentially. Each wafer fixing component has a first wafer fixing groove and a second wafer fixing groove of different depths, and wafers of different sizes are supported by the first wafer fixing groove and the second wafer fixing groove respectively.

[0006] The wafer fixing assembly includes a main support rod with multiple protrusions arranged linearly and equidistantly on the main support rod. The first wafer fixing groove is formed on the end face of each of the protrusions, and the second wafer fixing groove is formed between two of the protrusions, with the depth of the second wafer fixing groove being greater than the depth of the first wafer fixing groove.

[0007] The width of the first wafer fixing groove and the second wafer fixing groove gradually decreases from the opening to the bottom; the bottom of the first wafer fixing groove and the second wafer fixing groove are provided with elastic clamping components for assisting in clamping the wafer.

[0008] The elastic clamping assembly includes an elastic post and an abutment structure;

[0009] The bottom of the first wafer fixing slot and the second wafer fixing slot are provided with insertion holes. One end of the elastic post is fixedly inserted into the insertion hole, and the other end of the elastic post is provided with an abutment structure. A rough-surfaced pad is installed on the abutment structure.

[0010] The elastic column includes an outer tube, an annular stop, a rod, a cylindrical limiting plate, and a compression spring. The annular stop is provided at the opening of the outer tube. One end of the rod passes through the annular stop and is inserted into the outer tube and connected to the cylindrical limiting plate. The other end of the rod is connected to the abutment structure.

[0011] The compression spring is housed inside the outer tube, with its two ends abutting against the bottom of the outer tube and the cylindrical limiting plate, respectively.

[0012] The contact structure includes a contact block with a V-shaped groove, and the pad is fixed to the inner wall of the V-shaped groove.

[0013] The side plate is a circular plate, and the side plate has a number of soaking liquid through holes and a number of fixing structures for installing the wafer fixing assembly.

[0014] The fixing structure includes a slot and a through hole at the bottom of the slot.

[0015] Both ends of the main support rod are integrally formed with plug-in blocks, and threaded blind holes are opened on the end face of the plug-in blocks; the plug-in blocks are inserted into the inside of the slot, so that the threaded blind holes correspond to the through holes, and are locked and fixed by fixing bolts.

[0016] The advantages and beneficial effects of this invention are: by setting several sets of wafer fixing components between two sets of side plates, and designing the first wafer fixing groove and the second wafer fixing groove on the wafer fixing components, wafers of different specifications can be clamped in a way that can accommodate wafers of various sizes, achieving the purpose of simple structure, convenient preparation, low cost, adjustability and space saving. Attached Figure Description

[0017] Figure 1 This is one of the isometric views of the chip box in one embodiment of the present invention;

[0018] Figure 2 This is a second isometric view of the cassette in one embodiment of the present invention;

[0019] Figure 3 This is a schematic diagram of the structure of a wafer fixing assembly in one embodiment of the present invention;

[0020] Figure 4 This is a schematic diagram of the side plate structure in one embodiment of the present invention;

[0021] Figure 5 This is a schematic diagram of the structure of an elastic clamping assembly in one embodiment of the present invention;

[0022] Figure 6 This is a schematic diagram of the structure of an elastic column in one embodiment of the present invention;

[0023] In the diagram: 1. Side plate; 2. Waist hole; 3. Waist fixing assembly; 4. First wafer fixing slot; 5. Second wafer fixing slot; 6. Fixing structure; 7. Main support rod; 8. Protrusion; 9. Insertion block; 10. Immersion solution through hole; 11. Threaded blind hole; 12. Through hole; 13. Slot; 15. Countersunk hole; 16. Elastic post; 17. Insertion hole; 18. Abutment structure; 19. Pad; 20. Outer sleeve; 21. Annular stop; 22. Insertion rod; 23. Cylindrical limiting plate; 24. Compression spring; 25. Abutment block; 26. V-groove; 27. Reinforcing plate; 100. Wafer cassette capable of accommodating wafers of various sizes. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The specific embodiments described herein are merely used to explain the present invention and are not intended to limit the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] One embodiment of the present invention provides a wafer cassette capable of accommodating wafers of various sizes. It features a simple structure, convenient fabrication, low cost, adjustability, and space-saving design. See also... Figure 1 , Figure 2 As shown, the wafer cassette capable of accommodating wafers of various sizes includes two sets of side plates 1 and multiple wafer fixing components 3 arranged circumferentially between the two sets of side plates 1. The multiple wafer fixing components 3 are arranged in parallel, and their two ends are fixedly connected to the two sets of side plates 1 respectively. Each wafer fixing component 3 has a first wafer fixing groove 4 and a second wafer fixing groove 5 with different depths on its inner side, which support wafers of different sizes respectively.

[0026] See Figure 3As shown in the embodiment of the present invention, the wafer fixing assembly 3 includes a main support rod 7, on which a plurality of protrusions 8 are linearly and equidistantly arranged. A first wafer fixing groove 4 is formed on the end face of each protrusion 8, and a second wafer fixing groove 5 is formed between two protrusions 8. The depth of the second wafer fixing groove 5 is greater than the depth of the first wafer fixing groove 4. That is, the first wafer fixing groove 4 is used to support small-sized wafers, and the second wafer fixing groove 5 is used to support large-sized wafers.

[0027] In one embodiment of the present invention, the widths of the first wafer fixing groove 4 and the second wafer fixing groove 5 gradually decrease from the opening to the bottom to facilitate wafer insertion and fixing. Specifically, the second wafer fixing groove 5 is formed by a wedge-shaped opening at the lower end between two adjacent protrusions 8. Therefore, without changing the length of the wafer cassette, the number of wafers that the cassette can hold is increased, allowing for the placement of two different sizes of wafers. If actual needs require, a structure that can hold more than two sizes can also be designed. Through the combined use of the first wafer fixing groove 4 and the second wafer fixing groove 5, wafers of various sizes can be supported and fixed, such as 8-inch and 6-inch or 8-inch and 4-inch wafers.

[0028] As an embodiment of the present invention, the bottom of the first wafer fixing groove 4 and the second wafer fixing groove 5 are both provided with elastic clamping components for assisting in clamping the wafer. The wafer is elastically supported by the elastic clamping components to avoid damaging the wafer.

[0029] See Figure 5 As shown, in an embodiment of the present invention, the elastic clamping assembly includes an elastic post 16 and an abutment structure 18; the bottom of the first wafer fixing groove 4 and the second wafer fixing groove 5 are provided with insertion holes 17, one end of the elastic post 16 is fixedly inserted into the insertion hole 17, and the other end of the elastic post 16 is provided with an abutment structure 18. A rough-surfaced pad 19 is installed on the abutment structure 18 to protect the wafer. In this embodiment, the pad 19 is a corrosion-resistant pad made of polytetrafluoroethylene.

[0030] See Figure 6 As shown, in an embodiment of the present invention, the elastic column 16 includes an outer sleeve 20, an annular stop 21, a rod 22, a cylindrical limiting plate 23, and a compression spring 24. The annular stop 21 is provided at the opening of the outer sleeve 20. One end of the rod 22 passes through the annular stop 21 and is inserted into the outer sleeve 20, connecting to the cylindrical limiting plate 23. The other end of the rod 22 is connected to the abutment structure 18. The compression spring 24 is housed within the outer sleeve 20, with both ends abutting against the bottom of the outer sleeve 20 and the cylindrical limiting plate 23, respectively. The compression spring 24 serves as a buffer. Preferably, the diameter of the cylindrical limiting plate 23 is 1-2 mm larger than the inner diameter of the annular stop 21.

[0031] See Figure 5As shown, in an embodiment of the present invention, the contact structure 18 includes a contact block 25, a V-shaped groove 26 is provided on the contact block 25, and a pad block 19 is fixed on the inner wall of the V-shaped groove 26. The V-shaped groove 26 further improves the support stability of the wafer.

[0032] See Figure 4 As shown, in an embodiment of the present invention, the side plate 1 is a circular plate, with a waist hole 2 in the middle. The side plate 1 also has several sets of immersion liquid through holes 10 and several sets of fixing structures 6 for mounting the wafer fixing assembly 3. In this embodiment, the fixing structure 6 includes a slot 13 and a through hole 12 disposed at the bottom of the slot 13. See also... Figure 3 As shown, the two ends of the main support rod 7 are integrally formed with plug-in blocks 9, and the end face of the plug-in block 9 is provided with threaded blind holes 11; the plug-in block 9 is inserted into the inside of the slot 13, so that the threaded blind hole 11 corresponds to the through hole 12, and is locked and fixed by fixing bolts.

[0033] As an embodiment of the present invention, a reinforcing plate 27 is fixed to the outer side of the main support rod 7 by fixing bolts. The reinforcing plate 27 has countersunk holes 15 at equal intervals, and the side wall of the main support rod 7 has mounting holes corresponding to the countersunk holes 15. One end of the fixing bolt passes through the countersunk hole 15 and is fixed inside the mounting hole. The strength of the film box is ensured by adding the reinforcing plate 27. The reinforcing plate 27 is made of stainless steel.

[0034] In this embodiment, the wafer is supported by the coordinated use of three sets of wafer fixing components 3, and the wafer is fixed and positioned by the coordinated use of elastic clamping components to prevent the wafer from falling out of the wafer cassette. This arrangement of the wafer fixing components 3 between the two sets of side plates 1, compared to existing wafer cassettes with outer shells, ensures that the wafer is fully in contact with the immersion solution during processes such as wafer soaking, guaranteeing thorough immersion.

[0035] Through embodiments of the present invention, a plurality of wafer fixing assemblies are arranged between two sets of side plates, and the design of the first wafer fixing groove and the second wafer fixing groove of the wafer fixing assemblies enables the clamping of wafers of different specifications. The structure is simple, easy to manufacture, low in cost, adjustable, and space-saving, accommodating wafers of various sizes. Compared with existing wafer cassettes with shells, this design ensures that the wafers are fully in contact with the immersion solution during processes such as wafer immersion, guaranteeing thorough immersion.

[0036] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A wafer cassette capable of accommodating wafers of multiple sizes, characterized in that, It includes two sets of side plates (1) and multiple wafer fixing components (3) arranged between the two sets of side plates (1) and distributed circumferentially. Each wafer fixing component (3) has a first wafer fixing groove (4) and a second wafer fixing groove (5) of different depths. The first wafer fixing groove (4) and the second wafer fixing groove (5) support wafers of different sizes respectively. The bottom of the first wafer fixing groove (4) and the second wafer fixing groove (5) are provided with elastic clamping components for assisting in clamping the wafers. The wafers are elastically supported by the elastic clamping components. The wafer fixing assembly (3) includes a main support rod (7), on which a plurality of protrusions (8) are arranged linearly and equidistantly. The first wafer fixing groove (4) is opened on the end face of each of the protrusions (8), and the second wafer fixing groove (5) is opened between two of the protrusions (8), and the depth of the second wafer fixing groove (5) is greater than the depth of the first wafer fixing groove (4). The elastic clamping assembly includes an elastic post (16) and an abutment structure (18). The bottom of the first wafer fixing groove (4) and the second wafer fixing groove (5) are provided with insertion holes (17). One end of the elastic post (16) is fixedly inserted into the insertion hole (17), and the other end of the elastic post (16) is provided with a contact structure (18). A rough pad (19) is installed on the contact structure (18). The elastic column (16) includes an outer tube (20), an annular stop (21), a plug rod (22), a cylindrical limiting plate (23), and a compression spring (24). The opening of the outer tube (20) is provided with an annular stop (21). One end of the plug rod (22) passes through the annular stop (21) and is inserted into the outer tube (20) and connected to the cylindrical limiting plate (23). The other end of the plug rod (22) is connected to the abutment structure (18). The compression spring (24) is housed inside the outer tube (20), and the two ends of the compression spring (24) abut against the bottom of the outer tube (20) and the cylindrical limiting plate (23), respectively.

2. The wafer cassette capable of accommodating wafers of multiple sizes according to claim 1, characterized in that, The contact structure (18) includes a contact block (25), on which a V-shaped groove (26) is provided, and the pad (19) is fixed on the inner wall of the V-shaped groove (26).

3. The wafer cassette capable of accommodating wafers of multiple sizes according to claim 1, characterized in that, The side plate (1) is a circular plate, and the side plate (1) is provided with a number of soaking liquid through holes (10) and a number of fixing structures (6) for installing the wafer fixing assembly (3).

4. The wafer cassette capable of accommodating wafers of multiple sizes according to claim 3, characterized in that, The fixing structure (6) includes a slot (13) and a through hole (12) at the bottom of the slot (13).

5. The wafer cassette capable of accommodating wafers of multiple sizes according to claim 4, characterized in that, The main support rod (7) has two integrally formed plug-in blocks (9) at both ends. The plug-in blocks (9) have threaded blind holes (11) on their end faces. The plug-in blocks (9) are inserted into the slot (13) so that the threaded blind holes (11) correspond to the through holes (12) and are locked in place by fixing bolts.

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