Silicon wafer cleaning method and silicon wafer cleaning system

Abstract

The invention provides a silicon wafer cleaning method and a silicon wafer cleaning system.The silicon wafer cleaning method comprises the steps that a flower basket loaded with silicon wafers is placed in a cleaning tank to be cleaned, and in the cleaning process or after cleaning is completed, the flower basket is converted into a second placement state from a first placement state; when cleaning is carried out in the cleaning tank, the flower basket is overturned from the first placement state to the second placement state, so that all-directional cleaning of the silicon wafers in the flower basket is facilitated, subsequent lifting according to the second placement state is also facilitated, and the problems of incomplete draining and mutual pollution of the silicon wafers in the tank type cleaning process can be effectively avoided; therefore, the problem of poor watermarks of silicon wafer products is solved.

Description

[0001] This application claims the priority of the Chinese patent application filed with the China Patent Office on April 19, 2024, with application number 202420829329.8 and title “A flower basket and cleaning device”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of photovoltaic production technology, and in particular to a silicon wafer cleaning method and cleaning system. Background Art

[0003] During the production of solar cells, silicon wafers and battery cells often need to be transferred between different tank-type cleaning equipment to achieve surface micro-machining and cleaning. In the prior art, baskets are generally used for centralized loading and transfer to improve production efficiency.

[0004] When cleaning silicon wafers, battery cells, etc., the baskets loaded with silicon wafers, battery cells, etc. need to be circulated in the cleaning tank. At this time, if the baskets are placed and circulated in an unstable or improper position, it may easily lead to problems such as inadequate cleaning of the silicon wafers in the baskets and poor product watermarks. Summary of the invention

[0005] The technical problem to be solved by the present application is to provide a silicon wafer cleaning method and a cleaning system to solve the problem that the existing method of using a basket to load silicon wafers for cleaning easily leads to inadequate cleaning of the silicon wafers in the basket and poor product watermarks.

[0006] In order to solve the above problems, the present application is implemented through the following technical solutions:

[0007] The present application proposes a silicon wafer cleaning method, which includes:

[0008] The flower basket loaded with silicon wafers is placed in a cleaning tank for cleaning;

[0009] During the cleaning process or after the cleaning is completed, the flower basket is changed from the first placement state to the second placement state.

[0010] Optionally, in the method, the flower basket is placed in or outside the cleaning tank and changed from the first placement state to the second placement state.

[0011] Optionally, in the method, the flower basket is changed from the first placement state to the second placement state in a liquid environment and / or a nitrogen environment.

[0012] Optionally, in the method, the flower basket is loaded with at least two layers of silicon wafers placed along a first direction;

[0013] The first placement state is changed to the second placement state, comprising:

[0014] The flower basket is turned over to change the flower basket from a first orientation placement state to a second orientation placement state.

[0015] Optionally, in the method, the number of the flower baskets is at least two and they are arranged in a row along a first direction;

[0016] Changing the flower basket from the first placement state to the second placement state comprises:

[0017] The flower baskets are changed from being arranged along the first direction to being arranged along the second direction.

[0018] Optionally, the number of the flower baskets is at least two, and before the flower baskets are changed from the first placement state to the second placement state, the method includes:

[0019] The spacing between adjacent flower baskets is adjusted so that there is a preset spacing between adjacent flower baskets along the second direction.

[0020] Optionally, in the method, the spacing between adjacent flower baskets is adjusted to a preset spacing in the cleaning tank; or, the flower baskets are transferred outside the cleaning tank, the spacing between adjacent flower baskets is adjusted to a preset spacing outside the cleaning tank, and then placed in another cleaning tank;

[0021] Alternatively, the flower baskets are transferred out of the cleaning tank one by one, and then placed in another cleaning tank one by one according to a preset spacing.

[0022] Optionally, the method further comprises: after cleaning is completed, drying the flower basket in the second placement state.

[0023] The present application also proposes a silicon wafer cleaning system, which includes at least one cleaning tank and a flipping mechanism;

[0024] The cleaning tank is used to accommodate a basket loaded with silicon wafers;

[0025] The turnover mechanism is used to change the flower basket from a first placement state to a second placement state during or after cleaning the flower basket.

[0026] Optionally, in the cleaning system, the flipping mechanism includes a flower basket seat and a driving unit, the flower basket seat is arranged in the cleaning tank to carry the flower basket, and the driving unit drives the flower basket seat to rotate so that the flower basket is changed from the first placement state to the second placement state.

[0027] Optionally, in the cleaning system, the flipping mechanism is disposed outside the cleaning tank, and is used to transfer the flower basket and drive the flower basket to change from the first placement state to the second placement state.

[0028] Optionally, the cleaning system further comprises a transfer mechanism, and the transfer mechanism is used to transfer the flower basket in the cleaning tank.

[0029] Optionally, in the cleaning system, the transfer mechanism includes a first transfer member and two second transfer members, and the two second transfer members are respectively arranged on both sides of the first transfer member.

[0030] Optionally, the cleaning system further includes a nitrogen purge mechanism, and the nitrogen purge mechanism is used to blow nitrogen into and / or outside the cleaning tank.

[0031] Optionally, in the cleaning system, the cleaning system further includes a drying device connected to the cleaning tank and used for drying the flower basket in the second placement state.

[0032] Compared with the prior art, this application has the following advantages:

[0033] The silicon wafer cleaning method of the present application places a flower basket loaded with silicon wafers in a cleaning tank for cleaning, and during or after the cleaning process, changes the flower basket from a first placement state to a second placement state; wherein, when cleaning in the cleaning tank, the flower basket is flipped from the first placement state to the second placement state, which is convenient for all-round cleaning of the silicon wafers in the flower basket and for subsequent lifting in the second placement state, and can effectively avoid the problems of incomplete drainage and mutual contamination of silicon wafers during the tank cleaning process, thereby improving the problem of poor watermarks on silicon wafer products.

[0034] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 A schematic diagram of a silicon wafer cleaning method provided in an embodiment of the present application;

[0036] Figure 2 A schematic diagram of a first flower basket placement state change process provided in an embodiment of the present application;

[0037] Figure 3 A schematic diagram of a second flower basket placement state change process provided in an embodiment of the present application;

[0038] Figure 4 A schematic diagram of a third flower basket placement state transformation process provided in an embodiment of the present application;

[0039] Figure 5 A schematic diagram of a fourth flower basket placement state transformation process provided in an embodiment of the present application;

[0040] Figure 6This is a schematic diagram of a flower basket from a first angle in an embodiment of the present application;

[0041] Figure 7 This is a schematic diagram of a flower basket from a second angle in an embodiment of the present application;

[0042] Figure 8 A schematic diagram of a fifth flower basket placement state change process provided in an embodiment of the present application;

[0043] Fig. 9 A schematic diagram of a first flower basket spacing adjustment process provided in an embodiment of the present application;

[0044] Fig.10 A schematic diagram of a second flower basket spacing adjustment process provided in an embodiment of the present application;

[0045] Fig.11 A schematic diagram of a third flower basket spacing adjustment process provided in an embodiment of the present application;

[0046] Fig.12 A schematic diagram of the first flower basket spacing and placement state transformation process provided in an embodiment of the present application;

[0047] Fig.13 A schematic diagram of a second process of changing the spacing and placement status of flower baskets provided in an embodiment of the present application;

[0048] Fig.14 This is a schematic diagram of the state of a double-layer flower basket placed in a cleaning tank in an embodiment of the present application;

[0049] Fig.15 A schematic diagram of the structure of a cleaning system provided in the first embodiment of the present application;

[0050] Fig.16 This is a schematic diagram of the combination of the flipping mechanism and the cleaning tank in the embodiment of the present application;

[0051] Fig.17 This is a schematic diagram of the structure of the transfer mechanism in the embodiment of the present application;

[0052] Fig.18 A schematic diagram of the structure of a cleaning system provided in the second embodiment of the present application;

[0053] Fig.19 This is a schematic diagram of the structure of the cleaning system provided in the third embodiment of the present application. DETAILED DESCRIPTION

[0054] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0055] It should be understood that the references to "one embodiment" or "an embodiment" throughout the specification mean that the specific features, structures, or characteristics associated with the embodiment are included in at least one embodiment of the present application. Therefore, the references to "in one embodiment" or "in an embodiment" appearing throughout the specification do not necessarily refer to the same embodiment. In addition, these specific features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0056] During the production of solar cells, silicon wafers and battery cells often need to be transferred in different processes. For example, after the finished square rods are sliced ​​and debonded, the silicon wafers need to be transported to the insert cleaning process for wet cleaning. During the cleaning and transportation process, they are generally loaded and transferred in a centralized manner through baskets. However, during the loading and transfer process, problems such as insufficient cleaning of the silicon wafers on the top of the basket, incomplete drainage of the silicon wafers, and poor product watermarks are likely to occur.

[0057] In view of the above problems, the present invention provides a method for cleaning a silicon wafer, such as Figure 1 As shown, it includes steps 101 to 102:

[0058] Step 101: placing the flower basket loaded with silicon wafers in a cleaning tank for cleaning.

[0059] In the above step 101, the silicon wafers are loaded into a basket, and then the basket is pulled into a cleaning tank for cleaning. The cleaning tank can be a liquid tank or gas tank such as a water tank, an acid tank, an alkali tank or a nitrogen tank, which has the effect of cleaning or washing the silicon wafers.

[0060] Step 102: during or after the cleaning process, the flower basket is changed from the first placement state to the second placement state.

[0061] In the above step 102, when cleaning the silicon wafers in the cleaning tank, the flower basket is controlled to change from the first placement state to the second placement state, that is, the flower basket is controlled to change its posture by flipping operations, etc., and by changing the posture, the silicon wafers in the flower basket can be more fully contacted with the cleaning material in the cleaning tank according to the cleaning needs, and impurities, oil stains, etc. on the silicon wafers can fall off more quickly, further improving the cleaning effect. Of course, the posture change can also be performed when the silicon wafers are pulled out of the cleaning tank without changing the posture in the cleaning tank, so as to facilitate the completion of the silicon wafer draining operation; and after the cleaning is completed (the number of cleaning tanks can be one or more, that is, after the cleaning is completed in the last cleaning tank, the cleaning is completed, otherwise it is all in the cleaning process), the flower basket is changed from the first placement state to the second placement state, so as to facilitate pulling with a suitable posture, avoiding problems such as unstable or improper position during circulation causing collisions between silicon wafers in the flower basket and poor product watermarks.

[0062] In the embodiment of the present application, the first placement state and the second placement state of the flower basket can be a determined or uncertain placement state, and the change of the flower basket from the first placement state to the second placement state is intended to indicate that the placement state of the flower basket has changed during or after cleaning.

[0063] In an embodiment of the present application, a flower basket loaded with silicon wafers is placed in a cleaning tank for cleaning, and during or after the cleaning process, the flower basket is changed from a first placement state to a second placement state; wherein, when cleaning in the cleaning tank, the flower basket is flipped from the first placement state to the second placement state, which can facilitate all-round cleaning of the silicon wafers in the flower basket according to the needs of cleaning, and also facilitate subsequent lifting in the second placement state, which can effectively avoid the problems of incomplete drainage and mutual contamination of silicon wafers during the tank cleaning process, thereby improving the problem of poor watermarks on silicon wafer products.

[0064] Optionally, in one embodiment, in the above step 102, changing the flower basket from the first placement state to the second placement state includes: placing the flower basket in or outside the cleaning tank and changing it from the first placement state to the second placement state.

[0065] In this embodiment, if Figure 2 As shown, when the flower basket 10 is suitable for changing the placement state in the cleaning tank 30, the flower basket can be directly changed from the first placement state to the second placement state in the cleaning tank by flipping, moving the position, etc.;

[0066] In this embodiment, if Figure 3 As shown, when the flower basket 10 is not suitable for changing the placement state in the cleaning tank 30, the flower basket can be changed from the first placement state to the second placement state outside the cleaning tank by flipping or the like.

[0067] Optionally, in one embodiment, in the step 102, the flower basket is changed from the first placement state to the second placement state in a liquid environment and / or a nitrogen environment.

[0068] In this embodiment, the flower basket is controlled to change from the first placement state to the second placement state in a liquid environment or a nitrogen environment, so that silicon wafer contamination can be avoided during the placement state change process.

[0069] When the flower basket is changed from the first placement state to the second placement state in a liquid environment, the cleaning tank is a liquid tank, that is, cleaning liquid such as water, acid or alkali needs to be added into the cleaning tank.

[0070] Among them, when the flower basket is changed from the first placement state to the second placement state in a nitrogen environment, the above-mentioned cleaning tank can be set as a nitrogen tank, that is, nitrogen needs to be introduced into the cleaning tank through a nitrogen purge mechanism. Specifically, a nitrogen pipeline can be set at the bottom of the cleaning tank, and nitrogen is introduced during the cleaning process of the flower basket. Nitrogen is provided from bottom to top, so that the cleaning tank presents a nitrogen environment. A nitrogen purge mechanism can also be set outside the cleaning tank. When the flower basket is changed from the first placement state to the second placement state, the flower basket is purged with nitrogen to perform gas protection to prevent the surface of the silicon wafer from being contaminated, oxidized, and other adverse phenomena.

[0071] Optionally, in one embodiment, the flower basket is loaded with at least two layers of silicon wafers placed along a first direction;

[0072] The first placement state is changed to the second placement state, comprising:

[0073] The flower basket is turned over to change the flower basket from a first orientation placement state to a second orientation placement state.

[0074] In this embodiment, the first direction is the direction in which the silicon wafers can be stably arranged and loaded in the flower basket, that is, the vertical direction; and the silicon wafers are stacked in at least two layers in the flower basket, which can significantly increase the silicon wafer loading capacity per unit area of ​​the flower basket.

[0075] In this embodiment, the first direction placement state is a flower basket placement state corresponding to the first direction, and this placement state is suitable for inserting the silicon wafer into the flower basket; the second direction placement state is a placement state different from the first direction placement state, that is, the horizontal direction. In this second direction placement state, the silicon wafers can not only be stably and independently arranged and loaded in the flower basket, but also avoid bumps and scratches between the silicon wafers in the flower basket due to unstable or improper position during circulation, and can also effectively avoid incomplete drainage during the trough cleaning process and mutual contamination between silicon wafers, resulting in poor product watermarks and other problems.

[0076] For example, when the basket 10 is loaded with two layers of silicon wafers placed along a first direction, when the first placement state is changed to the second placement state in a single cleaning tank 30, specifically, Figure 4 shown.

[0077] For example, when the basket 10 is loaded with two layers of silicon wafers placed along a first direction, when the first placement state is changed to the second placement state outside the cleaning tank 30, specifically, Figure 5 shown.

[0078] In the embodiment of the present application, the above-mentioned flower basket can be a single-layer flower basket or a multi-layer flower basket, wherein the single-layer flower basket is a flower basket with only one layer of accommodating space; the multi-layer flower basket is a flower basket with multiple layers of accommodating space, and the multi-layer accommodating space can specifically be 2 layers, 3 layers, 4 layers, etc. The above-mentioned accommodating space is a space for loading single-layer silicon wafers in an upright state. Because each layer of accommodating space can hold silicon wafers, the design of the multi-layer accommodating space enables the above-mentioned flower basket to insert multiple layers of silicon wafers, which can significantly increase the silicon wafer loading capacity per unit area of ​​the flower basket.

[0079] For example, Figure 6 , 7 As shown, the flower basket 10 provided in the embodiment of the present application has a multi-layer accommodating space 20 formed by multiple connecting rods 12 and two fixed plates 11, for example, N-layer accommodating space, where N can be 2, 3 or 4, etc., which can achieve the silicon wafer loading capacity of N single-layer flower baskets. Therefore, when the silicon wafers are wet-tank cleaned, it is equivalent to expanding the number of flower baskets placed in a single cleaning tank to N times while keeping the floor area of ​​the cleaning tank unchanged. This can not only achieve a huge increase in the equipment's production capacity, but also effectively reduce the consumption of chemicals.

[0080] Optionally, in a specific implementation, when the flower basket is a multi-layer flower basket, in the step 102, changing the flower basket from the first placement state to the second placement state includes: flipping the flower basket from an upright state to a lying state.

[0081] In this specific embodiment, when in an upright state, the flower basket has multiple layers of storage space, and the above storage space is used to store silicon wafers in an upright state; while in a lying state, the flower basket has only one layer of storage space, so that when the flower basket is lifted in a lying state, the residual liquid medicine on the upper silicon wafer will not flow to the lower silicon wafer, thereby avoiding the generation of water marks and other adverse effects on the appearance.

[0082] In this specific embodiment, when the flower basket is a multi-layer flower basket with multi-layer accommodating space, the overall height of the flower basket is lowered by flipping, so that the silicon wafers on the upper layer of the flower basket can contact the cleaning material according to the need of cleaning. At the same time, the impurities, oil stains, etc. on the silicon wafers can fall off more quickly through the flipping operation, further improving the cleaning effect. On the other hand, the flower basket is flipped from an upright state to a flat state, while the silicon wafers are still in an upright state, and the multi-layer silicon wafers are arranged side by side in the horizontal direction. Therefore, when the flower basket is lifted in a flat state, the silicon wafers of each layer will not be contaminated with each other due to the multi-layer distribution in the vertical direction, and the upper silicon wafers and the lower silicon wafers will not be contaminated with each other due to residual liquid, and there will be pollution and bad watermarks caused by drainage.

[0083] Optionally, in one embodiment, the flower baskets are provided in at least two numbers and are arranged along the first direction;

[0084] Changing the flower basket from the first placement state to the second placement state comprises:

[0085] The flower baskets are changed from being arranged along the first direction to being arranged along the second direction.

[0086] In this embodiment, the first direction is an arrangement direction for placing multiple flower baskets in the cleaning tank, for example, a vertical direction; when silicon wafers are loaded in the flower baskets and cleaned in the cleaning tank, at least two flower baskets are arranged along the first direction to facilitate cleaning of multiple flower baskets at the same time.

[0087] In this embodiment, the second direction is a direction different from the first direction, and specifically can be an arrangement direction that is convenient for transporting multiple flower baskets, such as a horizontal direction; during the cleaning process or after cleaning is completed, the flower baskets are changed from being arranged along the first direction to being arranged along the second direction, so that the silicon wafers in the flower baskets at different arrangement positions can contact with the cleaning material by adjusting the arrangement method, and the impurities, oil stains, etc. on the silicon wafers can fall off more quickly by adjusting the arrangement position, thereby further improving the cleaning effect; at the same time, after cleaning is completed, the flower baskets are changed to be arranged along the second direction, so that the flower baskets are at least offset from each other in the vertical direction, which is convenient for the robot to carry and transport, and can also avoid the problem of water contamination between the silicon wafers in each flower basket.

[0088] For example, when two flower baskets 10 are provided, the first direction is the vertical direction, and the second direction is the horizontal direction, as shown in the following example: Figure 8 In the manner shown, the two flower baskets are arranged in the cleaning tank 30 in a second direction instead of being arranged in a first direction.

[0089] Optionally, in one embodiment, at least two flower baskets are provided. The silicon wafer cleaning method provided in the embodiment of the present application further includes step 103 before the flower basket is changed from the first placement state to the second placement state:

[0090] Step 103: adjusting the distance between adjacent flower baskets so that there is a preset distance between adjacent flower baskets along the second direction.

[0091] In this embodiment, before the flower basket is changed from the first placement state to the second placement state, the spacing between adjacent flower baskets along the second direction is adjusted to a preset spacing by a robot or a transfer mechanism, and the existence of the preset spacing enables the flower basket to be changed from the first placement state to the second placement state.

[0092] In practical applications, the second direction is a direction corresponding to the second placement state, specifically a direction that affects whether the flower basket can be placed in the second placement state.

[0093] For example, when there are two flower baskets, if in the first placement state the two flower baskets are arranged horizontally side by side in an upright state, and in the second placement state the two flower baskets are arranged horizontally side by side in a lying state in the first placement state, then the second direction is the horizontal direction.

[0094] For example, when there are two flower baskets, if in the first placement state the two flower baskets are arranged vertically side by side in a lying state, and in the second placement state the two flower baskets are arranged vertically side by side in an upright state in the first placement state, then the second direction is the vertical direction.

[0095] Optionally, in a specific embodiment, the distance between adjacent flower baskets is adjusted to a preset distance in the cleaning tank.

[0096] In this specific implementation, Fig. 9 As shown, when the internal space of the cleaning tank 30 at least in the second direction is large enough, the distance between adjacent flower baskets is directly adjusted to a preset distance in the cleaning tank 30 .

[0097] Optionally, in a specific implementation, the flower baskets are transferred outside the cleaning tank, the spacing between adjacent flower baskets is adjusted to a preset spacing outside the cleaning tank, and then placed into another cleaning tank.

[0098] In this specific implementation, multiple flower baskets are simultaneously transferred out of the cleaning tank, and then the distance between adjacent flower baskets in the second direction is adjusted to a preset spacing, and then placed in another cleaning tank, so that the spacing between adjacent flower baskets in the other cleaning tank becomes the preset spacing.

[0099] This specific implementation is suitable for the case where the internal space of the cleaning tank in the second direction is insufficient or is not suitable for adjusting the spacing between the flower baskets.

[0100] For example, the flower basket state transformation process of this specific embodiment is as follows: Fig.10 shown.

[0101] Optionally, in a specific implementation, the flower baskets are transferred out of the cleaning tank in sequence, and then placed in another cleaning tank in sequence according to a preset interval.

[0102] In this specific implementation, the flower baskets are transferred out of the cleaning tank one by one, and then placed in another cleaning tank in sequence according to a preset spacing, so that the spacing between adjacent flower baskets in the other cleaning tank can also become the preset spacing.

[0103] For example, the flower basket state transformation process of this specific embodiment is as follows: Fig.11 shown.

[0104] In the embodiment of the present application, after adjusting the spacing between adjacent flower baskets to a preset spacing, each flower basket can be directly changed from the first placement state to the second placement state in the current cleaning tank; or each flower basket can be transferred to another cleaning tank, and the flower basket can be changed from the first placement state to the second placement state in the other cleaning tank.

[0105] Optionally, in one embodiment, the flower basket is cleaned in a first cleaning tank in a first placement state, then lifted and translated to a second cleaning tank, and the spacing between adjacent flower baskets is adjusted to a preset spacing in the second cleaning tank, and then each flower basket is lifted and translated to a third cleaning tank, and each flower basket is changed from the first placement state to the second placement state in the third cleaning tank. The corresponding process is as follows: Fig.12 shown.

[0106] In this embodiment, the first cleaning tank is a tank for cleaning the flower baskets; the second cleaning tank is a tank for expanding the distance between the flower baskets to facilitate subsequent posture changes; and the third cleaning tank is a tank for posture changes of the flower baskets.

[0107] In a specific embodiment, when the flower basket is a multi-layer flower basket and the first placement state is an upright placement state, the first cleaning tank is used to accommodate the flower basket in an upright state and having a multi-layer accommodating space; in a specific embodiment, when the flower basket is a multi-layer flower basket and the second placement state is a lying state, compared with the first cleaning tank, the second cleaning tank and the third cleaning tank can be widened to accommodate the flower basket in the lying state.

[0108] In this specific implementation, Fig.13As shown, one or more flower baskets 10 are first placed in a first cleaning tank 31 with a small spacing for cleaning; then the flower baskets 10 are pulled apart and placed in a second cleaning tank 32 by lifting and translating, so as to expand the spacing between the flower baskets 10, so as to facilitate the subsequent posture change operation. Compared with the first cleaning tank 31, the second cleaning tank 32 can be widened to match the larger spacing between adjacent flower baskets, so as to facilitate the flower baskets to be transferred to the third cleaning tank in groups for direct posture change operation; then the flower baskets 10 in the second cleaning tank 32 are lifted and translated into the third cleaning tank 33 in groups of at least two and turned to a flat state, so as to reduce the adverse appearance effects such as water marks caused by the residual liquid on the upper silicon wafer of the flower basket flowing to the lower silicon wafer during subsequent dehydration and drying. Compared with the first cleaning tank, the third cleaning tank can also be widened to accommodate the flower baskets in a flat state.

[0109] In this specific embodiment, the distance between the two adjacent flower baskets in the second cleaning tank can be adjusted to be greater than the height of the flower baskets in an upright state, so that when the flower baskets are transferred to the third cleaning tank in groups, the flower baskets can be flipped without adjusting the distance between them.

[0110] Optionally, in an embodiment of the present application, the above-mentioned pulling process is carried out along a first direction, and the angle between the first direction and the horizontal direction is 70 to 90 degrees, that is, when the flower basket is pulled to the first cleaning tank / the second cleaning tank / the third cleaning tank or pulled out of the first cleaning tank / the second cleaning tank / the third cleaning tank, it is carried out in a vertical direction or a direction close to the vertical direction, so that the flower basket can be quickly lifted out.

[0111] When extracting the flower basket, the flower basket is lifted until the bottom of the flower basket is beyond the top of the cleaning tank.

[0112] Optionally, in an embodiment of the present application, the above-mentioned translation process is carried out along the second direction, and the angle between the second direction and the horizontal direction is 0 to 30°, that is, when the flower basket is translated to above the first cleaning tank / the second cleaning tank / the third cleaning tank or moved away from above the first cleaning tank / the second cleaning tank / the third cleaning tank, it is carried out in a horizontal direction or a direction close to the horizontal direction, so that the flower basket can be transferred smoothly.

[0113] In practical applications, during the translation of the flower basket, the flower basket can be controlled to translate at a second rate, that is, the flower basket is controlled to translate at a fixed rate; or the flower basket can be controlled to translate at a first rate, a second rate, and a third rate in sequence, wherein the second rate is greater than the first rate and the third rate, that is, the flower basket is translated at a slower rate at the beginning, at a faster rate in the middle, and at a slower rate at the end.

[0114] Optionally, in a specific embodiment, the pulling time is controlled to be 20 to 50 s, for example, one of 20s, 30s, 40s, 50s or a range value between any two of them, and the flipping time is controlled to be 10 to 30 s, for example, one of 10s, 12s, 15s, 20s, 30s or a range value between any two of them, which can effectively take into account the flower basket transfer efficiency and the cleaning effect of silicon wafer drainage.

[0115] Optionally, in one implementation, the silicon wafer cleaning method provided in the embodiment of the present application further includes step 104:

[0116] Step 104: After cleaning is completed, the flower basket is dried in the second placement state.

[0117] In this embodiment, the flower basket is horizontally moved to a drying device such as an oven for drying in the second placement state, which can effectively improve the adverse appearance effects such as water marks. In particular, when the flower basket is a multi-layer flower basket, it can effectively prevent the upper silicon wafer from leaking water to the lower silicon wafer, thereby causing contamination of the lower silicon wafer.

[0118] In practical applications, after the flower basket is lifted to the third cleaning tank, the total operation time from flipping to lifting the flower basket to the drying equipment is controlled to be 100-150s, for example, a range value between one of 100s, 110s, 120s, 130s, 140s, 150s or any two thereof. Compared with the lifting between the cleaning tanks during the cleaning process, the operation time of lifting the flower basket in the cleaning tank after the cleaning is completed is longer, that is, the flower basket after cleaning is lifted by a slow lifting method to transfer the flower basket or perform subsequent drying operations. The slow lifting method can avoid collisions between silicon wafers and damage on the one hand, and can also allow sufficient time for the flower basket to lie flat at this time, so that the silicon wafers in the flower basket can be drained more thoroughly.

[0119] In practical applications, the cleaning tank can be an alkaline cleaning tank, a water tank, a mixed acid tank, an ozone cleaning tank, a slow pulling tank, a nitrogen tank, etc.

[0120] The cleaning method provided in the embodiment of the present application is further described below by taking a double-layer flower basket with two layers of accommodating space, in which the first placement state is an upright state and the second placement state is a lying state as an example.

[0121] (1) First, the first flower basket 21 and the second flower basket 22 are placed in an upright position in the first cleaning tank 31 for cleaning. Fig.14 As shown, the first flower basket and the second flower basket are both flower baskets with double-layer accommodation space and each layer of accommodation space accommodates a silicon wafer 13 in an upright state;

[0122] (2) Then, the long hanging plate of the robot arm is used to lift the first flower basket and the second flower basket respectively and move them in a translational manner to place them into the second cleaning tank;

[0123] (3) The robot arm is controlled to move downward, and the first and second flower baskets are lifted by the robot arm at the same time, and translated to the top of the third cleaning tank. The robot arm is then controlled to move downward, and the first and second flower baskets are respectively placed on different flipping brackets in the third cleaning tank. The flipping brackets are then driven by the rotating motor to move, thereby flipping the first and second flower baskets to a flat state with two layers of silicon wafers side by side.

[0124] (4) The rear robot arm slowly pulls the first flower basket and the second flower basket in a horizontal state, and each flower basket is lifted out and placed in a subsequent drying device for a drying process.

[0125] Tests have shown that, compared with the method of slowly lifting the flower basket directly in an upright state, the method of flipping the flower basket to a flat state can reduce the watermark defect rate of silicon wafer products from 15% to 1%.

[0126] The present application also provides a silicon wafer cleaning system 100. Figures 15 to 17 , including at least one cleaning tank 30 and a flipping mechanism 40, wherein the cleaning tank 30 is used to accommodate a flower basket 10 loaded with silicon wafers 10, and the flipping mechanism 40 is used to change the flower basket 10 from a first placement state to a second placement state during or after cleaning the flower basket 10.

[0127] In the silicon wafer cleaning system provided in the embodiment of the present application, due to the presence of the flipping mechanism, the flower basket can be changed from the first placement state to the second placement state during or after the flower basket is cleaned, which is convenient for all-round cleaning of the silicon wafers in the flower basket and subsequent lifting according to the second placement state. The problem of incomplete drainage and mutual contamination of silicon wafers during the trough cleaning process can be effectively avoided, thereby improving the problem of poor watermarks on silicon wafer products.

[0128] The first placement state and the second placement state of the flower basket may be determined or uncertain. The change of the flower basket from the first placement state to the second placement state is intended to indicate that the placement state of the flower basket has changed during or after cleaning.

[0129] In this embodiment, in order to increase the loading capacity and improve the cleaning efficiency, multiple flipping mechanisms are arranged at intervals in the cleaning tank, which can carry multiple of the above-mentioned flower baskets, and can significantly increase the silicon wafer cleaning volume in a single cleaning process.

[0130] Optionally, in one embodiment, Fig.15As shown, the flip mechanism 40 can be disposed outside the cleaning tank, and can transform the flower basket 10 from the first placement state to the second placement state outside the cleaning tank after the flower basket 10 is cleaned.

[0131] In this embodiment, by additionally providing a turning mechanism 40 outside the cleaning tank, the turning mechanism can be used to control the turning of the flower basket after cleaning is completed, and the flower basket can be controlled to change from the first placement state to the second placement state without modifying the cleaning tank.

[0132] Optionally, in a specific embodiment, the flipping mechanism 40 includes a robot, which is disposed on the top of the cleaning tank and is used to clamp the flower basket and control the flipping of the flower basket.

[0133] In this specific embodiment, by additionally arranging a robot outside the cleaning tank, the robot can be used to control the flower basket to flip during the cleaning process, and the flower basket can be controlled to change from the first placement state to the second placement state without modifying the cleaning tank.

[0134] Alternatively, in another embodiment, Fig.16 As shown, the flipping mechanism 40 can be arranged in the cleaning tank, and can change the flower basket 10 from the first placement state to the second placement state in the cleaning tank 30 during the cleaning process of the flower basket 10, or change the flower basket 10 from the first placement state to the second placement state in the cleaning tank after the flower basket 10 is cleaned; wherein, the flower basket 10 is carried on the flipping mechanism 40, and the flipping of the flipping mechanism 30 drives the flower basket 10 to flip, that is, the flower basket 10 can be changed from the first placement state to the second placement state in the cleaning tank.

[0135] The above-mentioned flipping mechanisms 40 may be provided in two in the cleaning tank 30, for respectively changing the two flower baskets 10 from the first placement state to the second placement state.

[0136] Optionally, in a specific embodiment, Fig.16 As shown, the turning mechanism 40 includes a flower basket seat 41 and a driving unit 42. The flower basket seat 41 is disposed in the cleaning tank 30 for carrying the flower basket 10. The driving unit 42 drives the flower basket seat 41 to rotate so that the flower basket 10 is changed from a first placement state to a second placement state.

[0137] The flower basket seat 41 can be arranged in the cleaning tank 30 via a horizontal rotating shaft 43, and the output end of the driving unit 42 is in transmission connection with the rotating shaft 43. The rotating shaft 43 can drive the flower basket seat 41 to rotate around the horizontal rotating shaft 43, and the flower basket 10 is loaded on the flower basket seat 41, and the flower basket 10 will also rotate with the rotation of the flower basket seat 41. Therefore, by controlling the rotation of the horizontal rotating shaft through the driving unit 42, the flip bracket 41 can be driven to rotate, and the flower basket 10 can be driven to flip, so as to realize the transformation of the flower basket from the first placement state to the second placement state.

[0138] In the embodiment of the present application, the cleaning tank 30 may be a liquid tank or a nitrogen tank, or a nitrogen purge mechanism may be provided outside the cleaning tank 30 to flip and lift the flower basket in a liquid environment or a nitrogen environment.

[0139] Optionally, the flower basket seat 41 has two mutually perpendicular bearing surfaces to respectively bear the flower basket in an upright state and a flat state.

[0140] Optionally, in a more specific embodiment, the flower basket seat 41 is L-shaped or bucket-shaped, which makes it easy to change the flower basket 10 from a lying state to an upright state or from an upright state to a lying state, and the lifting device can smoothly lift the flower basket regardless of the upright state or the lying state.

[0141] The driving unit 42 may be a motor, and the output end of the motor is connected to the rotating shaft 43 via a transmission belt 44. Optionally, a rotating gear 45 is provided at one end of the rotating shaft 43, and the transmission belt 44 is wound around the rotating gear 45 and the output end of the motor, thereby realizing a transmission connection between the rotating shaft 43 and the motor.

[0142] Optionally, in a more specific embodiment, when the cleaning tank 30 is a liquid tank, Fig.16 As shown, the motor is arranged above the cleaning tank through a cantilever to protect the motor from being corroded by liquid.

[0143] Optionally, in another specific embodiment, when the cleaning tank 30 is a nitrogen tank, the motor is disposed at the bottom of the cleaning tank and is transmitted to the rotating shaft 43 through a conveyor belt 44 or a rotating gear 45 to improve driving efficiency.

[0144] Optionally, in one embodiment, the cleaning system provided in the embodiment of the present application further includes a transfer mechanism 50, which is used to transfer the flower baskets in the cleaning tank so as to adjust the spacing between adjacent flower baskets before changing the flower baskets from the first placement state to the second placement state, so that there is a preset spacing between adjacent flower baskets along the second direction.

[0145] The transfer mechanism can adjust the spacing between adjacent flower baskets to a preset spacing in the cleaning tank; or transfer the flower baskets to outside the cleaning tank, adjust the spacing between adjacent flower baskets to a preset spacing outside the cleaning tank, and then place them in another cleaning tank; or transfer the flower baskets out of the cleaning tank one by one, and then place them in another cleaning tank one by one according to the preset spacing.

[0146] Optionally, in a specific embodiment, Fig.17 As shown, the transfer mechanism 50 includes a first transfer member 51 and two second transfer members 52, and the two second transfer members 52 are respectively arranged on both sides of the first transfer member 51. The first transfer member 51 is used to lift a single flower basket 10 into the cleaning tank 30, and the second transfer member is used to lift two flower baskets 10 in groups into the cleaning tank 30 or out of the cleaning tank 30. Optionally, the first transfer member 51 can be a long hanging plate, and the second transfer member 52 can be a short hanging plate.

[0147] Optionally, in a specific embodiment, Fig.15 As shown, the at least one cleaning tank 30 includes a first cleaning tank 31, which is used to clean the flower basket and change the flower basket from the first placement state to the second placement state during or after the cleaning process.

[0148] Among them, the internal space of the first cleaning tank is sufficient to accommodate the flower baskets in the first placement state and the second placement state; optionally, the flower basket is a multi-layer flower basket loaded with at least two layers of silicon wafers placed along the first direction, and the first placement state is an upright state, and the second placement state is a lying state, and the first cleaning tank can be heightened along the first direction to accommodate the flower basket in the upright state and with a multi-layer accommodating space.

[0149] Optionally, in a specific embodiment, Fig.18 As shown, the at least one cleaning tank 30 includes a first cleaning tank 31 and a second cleaning tank 32. The first cleaning tank is used to clean the flower basket in the first placement state; the second cleaning tank is used to accommodate the flower basket changed from the first placement state to the second placement state.

[0150] Wherein, the internal space of the first cleaning tank is sufficient to accommodate the flower basket in the first placement state;

[0151] Optionally, the flower basket is a multi-layer flower basket loaded with at least two layers of silicon wafers placed along a first direction, and the first placement state is an upright state, and the second placement state is a flat state. The first cleaning tank should be heightened along the first direction to accommodate the flower basket in an upright state and having multi-layer accommodating space; the second cleaning tank is widened to accommodate the flower basket 10 in a flat state.

[0152] Optionally, in a specific embodiment, Fig.19 As shown, the at least one cleaning tank 30 includes a first cleaning tank 31, a second cleaning tank 32 and a third cleaning tank 33; the first cleaning tank 31 is used to clean at least two flower baskets in a first placement state; the second cleaning tank 32 is used to accommodate at least two flower baskets with a preset distance in the second direction before the flower baskets are changed from the first placement state to the second placement state; the third cleaning tank 33 is used to accommodate the flower baskets changed from the first placement state to the second placement state.

[0153] Optionally, the flower basket is a multi-layer flower basket loaded with at least two layers of silicon wafers placed along a first direction, and the first placement state is an upright state, and the second placement state is a flat state, then the first cleaning tank can be heightened to accommodate the flower basket in an upright state and having a multi-layer accommodating space; the second cleaning tank is a tank used to expand the distance between the flower baskets for subsequent flipping; the third cleaning tank is a tank used to flip the flower basket, and compared with the first cleaning tank, the third cleaning tank should be widened to accommodate the flower basket in a flat state.

[0154] In this specific embodiment, one or more flower baskets 10 are first placed in a first cleaning tank 31 with a small spacing for cleaning; then the flower baskets 10 are pulled apart and placed in a second cleaning tank 32 by lifting and translating, thereby increasing the spacing between the flower baskets 10 for subsequent flipping operations. Compared with the first cleaning tank 31, the second cleaning tank 32 should be widened to match the larger spacing between adjacent flower baskets, so that the flower baskets can be transferred to the third cleaning tank in groups for direct flipping; then Figure 4 As shown, the flower baskets 10 in the second cleaning tank 32 are lifted and translated into the third cleaning tank 33 in groups of at least two and turned over to a flat state, so as to reduce the adverse effects on appearance such as water marks caused by residual liquid on the upper silicon wafer of the flower basket flowing to the lower silicon wafer during subsequent dehydration and drying. Compared with the first cleaning tank, the third cleaning tank should also be widened to accommodate the flower baskets in a flat state.

[0155] Optionally, in a specific embodiment, the distance between two adjacent flower baskets in the second cleaning tank is greater than the height of the flower baskets in an upright state, so that when the flower baskets are transferred to the third cleaning tank in groups, the flower baskets can be flipped without adjusting the distance between them.

[0156] In practical applications, such as Fig.18 As shown, the width of the second cleaning tank 32 is sufficient to facilitate at least two grippers of the robot arm to simultaneously grip at least two of the above-mentioned flower baskets in groups, that is, when the robot arm simultaneously grips the first flower basket 21 and the second flower basket 22, smooth operation can be ensured.

[0157] Optionally, in one embodiment, Fig.15 ,18 As shown in Figure 19, the cleaning system provided in the embodiment of the present application further includes a nitrogen purge mechanism 60, which is used to blow nitrogen into and / or outside the cleaning tank, thereby creating a nitrogen environment for the flower basket, so as to transform the flower basket from the first placement state to the second placement state under the nitrogen environment.

[0158] Optionally, in a specific embodiment, the nitrogen purge mechanism includes a nitrogen pipeline (not shown) disposed at the bottom of the cleaning tank 60, and the nitrogen pipeline is used to provide nitrogen to the bottom of the cleaning tank.

[0159] Optionally, in one embodiment, Fig.15 , 18 As shown in Figures 19, the cleaning system provided in the embodiment of the present application further includes a drying device 70, which is connected to the cleaning tank 30 and is used to dry the flower basket in the second placement state.

[0160] The drying device 70 may be an oven or the like.

[0161] In summary, in this embodiment, the flower basket is flipped from an upright state to a flat state during cleaning in the cleaning tank, which is convenient for all-round cleaning of the silicon wafers in the flower basket and also convenient for subsequent lifting in a flat state. Lifting the flower basket in a flat state can effectively avoid the problem of residual liquid in the upper space contaminating the lower space during the tank cleaning process, thereby improving the problem of poor watermarks on silicon wafer products.

[0162] It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0163] Although the optional embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including optional embodiments and all changes and modifications that fall within the scope of the present application.

[0164] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity from another entity, and do not necessarily require or imply any such actual relationship or order between these entities. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that an article or terminal device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such article or terminal device. In the absence of further restrictions, the elements defined by the sentence "including one..." do not exclude the existence of other identical elements in the article or terminal device including the elements.

[0165] The technical solution provided by the present application is introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. At the same time, for those skilled in the art, according to the principles and implementation methods of the present application, there may be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as limiting the present application.

Claims

1. A silicon wafer cleaning method, characterized in that: include: The flower basket loaded with silicon wafers is placed in a cleaning tank for cleaning; During the cleaning process or after the cleaning is completed, the flower basket is changed from the first placement state to the second placement state.

2. The cleaning method according to claim 1, characterized in that The flower basket is placed in or outside the cleaning tank and changed from the first placement state to the second placement state.

3. The cleaning method according to claim 1, characterized in that The flower basket is placed in a liquid environment and / or a nitrogen environment, and is changed from the first placement state to a second placement state.

4. The cleaning method according to claim 1, characterized in that: The flower basket is loaded with at least two layers of silicon wafers placed along a first direction; The first placement state is changed to the second placement state, comprising: The flower basket is turned over to change the flower basket from a first orientation placement state to a second orientation placement state.

5. The cleaning method according to claim 1, characterized in that: The number of the flower baskets is at least two and they are arranged in a row along a first direction; Changing the flower basket from the first placement state to the second placement state comprises: The flower baskets are changed from being arranged along the first direction to being arranged along the second direction.

6. The cleaning method according to claim 1, characterized in that: The flower baskets are provided with at least two, and before the flower baskets are changed from the first placement state to the second placement state, the method further comprises: The spacing between adjacent flower baskets is adjusted so that there is a preset spacing between adjacent flower baskets along the second direction.

7. The cleaning method according to claim 6, characterized in that: Adjusting the distance between adjacent flower baskets to a preset distance in the cleaning tank; or transferring the flower baskets to outside the cleaning tank, adjusting the distance between adjacent flower baskets to a preset distance outside the cleaning tank, and then placing the flower baskets in another cleaning tank; Alternatively, the flower baskets are transferred out of the cleaning tank one by one, and then placed in another cleaning tank one by one according to a preset spacing.

8. The method according to any one of claims 1 to 5, characterized in that: Also includes: After cleaning is completed, the flower basket is dried in the second placement state.

9. A silicon wafer cleaning system, characterized in that: It includes at least one cleaning tank and a turning mechanism; The cleaning tank is used to accommodate a basket loaded with silicon wafers; The turnover mechanism is used to change the flower basket from a first placement state to a second placement state during or after cleaning the flower basket.

10. The cleaning system according to claim 9, characterized in that: The flip mechanism includes a flower basket seat and a driving unit. The flower basket seat is arranged in the cleaning tank for carrying the flower basket. The driving unit drives the flower basket seat to rotate so that the flower basket is changed from the first placement state to the second placement state.

11. The cleaning system according to claim 9, characterized in that: The turning mechanism is arranged outside the cleaning tank, and is used for transferring the flower basket and driving the flower basket to change from the first placement state to the second placement state.

12. The cleaning system according to claim 9, characterized in that: It also includes a transfer mechanism, which is used to transfer the flower basket in the cleaning tank.

13. The cleaning system according to claim 12, characterized in that: The transfer mechanism comprises a first transfer member and two second transfer members, and the two second transfer members are respectively arranged on both sides of the first transfer member.

14. The cleaning system according to claim 9, characterized in that: It also includes a nitrogen purge mechanism, which is used to blow nitrogen into the cleaning tank and / or outside the cleaning tank.

15. The cleaning system according to claim 9, characterized in that: The cleaning system further comprises a drying device connected to the cleaning tank and used for drying the flower basket in the second placement state.

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