CN112405339A

CN112405339A - Temporary storage placing system for polishing silicon wafers

Info

Publication number: CN112405339A
Application number: CN202011404818.1A
Authority: CN
Inventors: 袁祥龙; 刘园; 武卫; 刘建伟; 由佰玲; 孙晨光; 王彦君; 常雪岩; 裴坤羽; 祝斌; 刘姣龙; 张宏杰; 谢艳; 杨春雪; 刘秒; 吕莹; 徐荣清
Original assignee: Tianjin Zhonghuan Advanced Material Technology Co Ltd; Zhonghuan Advanced Semiconductor Materials Co Ltd
Current assignee: Tianjin Zhonghuan Advanced Material Technology Co Ltd; Zhonghuan Advanced Semiconductor Materials Co Ltd
Priority date: 2020-12-05
Filing date: 2020-12-05
Publication date: 2021-02-26

Abstract

A temporary storage system for polishing silicon wafers comprises an uploading temporary storage mechanism for storing the silicon wafers to be polished; a loading temporary storage mechanism for placing the polished silicon wafer; the drive cleaning mechanism is used for driving the uploading temporary storage mechanism and the downloading temporary storage mechanism to rotate and spraying the non-polishing surface of the silicon wafer placed on the uploading temporary storage mechanism or the downloading temporary storage mechanism; the upper loading temporary storage mechanism enables the surface of the silicon wafer to be polished to be soaked by the solution; the temporary storage mechanism is downloaded to ensure that the polished surface of the silicon wafer is protected by the solution and cleaned; the uploading temporary storage mechanism and the downloading temporary storage mechanism are arranged around the driving cleaning mechanism. The invention synchronously and stably temporarily stores a plurality of groups of uploaded or downloaded silicon wafers, not only completely soaks the surface to be polished of the uploaded silicon wafers, but also protects the non-polished surface of the uploaded silicon wafers; and the polishing surface of the silicon wafer is completely isolated from air in a water liquid environment, and the polishing liquid and impurities on the non-polishing surface of the silicon wafer are cleaned and removed.

Description

Temporary storage placing system for polishing silicon wafers

Technical Field

The invention belongs to the technical field of silicon wafer polishing equipment, and particularly relates to a temporary storage system for polishing a silicon wafer.

Background

In the current semiconductor silicon wafer market, with the requirements of increasing the chip quantity and unit cost of a single semiconductor silicon wafer, the existing semiconductor silicon wafer gradually develops towards large-size and thin-slice. Correspondingly, in the chemical mechanical polishing process of large-size silicon wafers, especially for silicon wafers requiring single-side polishing, multiple wafers can not be polished in the same polishing disk as small-size silicon wafers, especially for large-size silicon wafers of 12 inches, 18 inches and above, each silicon wafer needs to be polished separately, and equipment for synchronously and independently polishing multiple groups of silicon wafers appears.

However, in the polishing machine process, in order to adapt to the synchronous and independent polishing of a plurality of groups of silicon wafers, how to ensure that the uploading temporary storage placement of the synchronously polished silicon wafers and the downloading temporary storage placement of the polished silicon wafers are prepared in advance before polishing; but also to satisfy: before polishing operation, ensuring that all polished surfaces of the silicon wafers in the loading temporary storage mechanism are completely soaked by water liquid and are not exposed in air to be polluted or oxidized; after polishing, the polishing surface of the silicon wafer placed in the temporary loading and placing mechanism is always in a water liquid environment, so that the surface of the polished surface is protected from being polluted or oxidized by particles, and the polishing quality of the silicon wafer is ensured; and meanwhile, the linkage of the cooperation of the uploading temporary storage placing mechanism and the downloading temporary storage placing mechanism with the upstream and downstream processes is improved, so that the key points of ensuring the polishing quality of the silicon wafer, improving the polishing efficiency and reducing the production cost are realized.

Disclosure of Invention

The invention provides a temporary storage system for polishing silicon wafers, which is particularly suitable for polishing equipment for synchronously and independently polishing a plurality of groups of silicon wafers and solves the technical problems that the surfaces of the silicon wafers to be polished are completely soaked by water liquid when the silicon wafers are polished and uploaded and the surfaces of the silicon wafers to be polished are completely isolated from air in a water liquid environment when the silicon wafers are downloaded.

In order to solve the technical problems, the invention adopts the technical scheme that:

a temporary storage system for polishing silicon wafers comprises:

an uploading temporary storage mechanism for placing the silicon wafer to be polished;

the downloading temporary storage mechanism is used for placing the polished silicon wafer;

the drive cleaning mechanism is used for driving the uploading temporary storage mechanism and the downloading temporary storage mechanism to rotate and spraying the non-polishing surface of the silicon wafer in the uploading temporary storage mechanism or the downloading temporary storage mechanism;

the uploading temporary storage mechanism enables the surface to be polished of the silicon wafer to be soaked by the solution;

the download temporary storage mechanism enables the polished surface of the silicon wafer to be protected by solution and cleaned;

the uploading temporary storage mechanism and the downloading temporary storage mechanism are wound on the driving cleaning mechanism.

Further, the upload temporary storage mechanism includes a plurality of upload devices disposed adjacent to each other, and the upload devices include:

an upper loading support assembly for supporting the silicon wafer;

the uploading overflow assembly is used for infiltrating the surface to be polished of the silicon wafer;

the upper loading support assembly is contacted with the side wall of the silicon wafer and enables the silicon wafer to be suspended, and the upper loading support assembly can move up and down along the height direction of the upper loading support assembly;

the upper loading overflow assembly is arranged in the upper loading support assembly and is arranged concentrically with the upper loading support assembly, and the upper loading overflow assembly is in full contact with the surface to be polished of the silicon wafer.

Further, the upload support assembly comprises:

a plurality of uploading columns;

the uploading mobile station is used for fixing and driving the uploading column to ascend and descend;

the upper loading column is arranged along the outer periphery of the upper loading overflow assembly, and the upper end face of the upper loading column is provided with a circular arc-shaped boss which is contacted with the side wall face of the silicon wafer;

the uploading mobile station is positioned below the uploading overflow assembly and is arranged at a gap with the uploading overflow assembly.

Further, the upload overflow assembly comprises:

the loading disc is fixedly arranged on the loading support assembly;

the elastic pad is arranged on the loading disc and can suck and discharge solution;

the upper loading overflow hole sequentially penetrates through the upper loading disc and the elastic cushion;

wherein, one side of the elastic cushion, which is far away from the upper loading disc, is provided with a plurality of annular brushes;

the upper loading overflow holes are distributed in the hairbrush gap.

Further, the upper loading overflow hole is provided at least at the center of the upper loading tray.

Further, the download temporary storage mechanism comprises a plurality of download devices which are arranged adjacently, and each download device is provided with:

a download placing component which stores a certain solution and makes the solution flow in a buffering way;

and a download supporting assembly which is used for supporting the silicon chip and can move up and down;

the downloading support assembly penetrates through the downloading placement assembly; and the circumscribed circle of the graph formed by the contact points of the download supporting assembly and the silicon wafer is connected with the same diameter as the silicon wafer.

Further, the download placement component comprises:

a download tray;

and a download overflow hole at least arranged at the center of the download disc;

the download tray is provided with an inner layer groove for storing solution and an outer layer groove matched with the contour of the inner layer groove; a plurality of lugs which are used for being penetrated by the downloading supporting component and are integrally arranged with the outer layer groove are arranged in the outer layer groove.

Further, the download support assembly comprises:

a plurality of lower loading columns arranged along the periphery of the outer layer groove;

the downloading placing rack is used for fixing the downloading columns;

the upper section of the downloading column is a cone, penetrates through the lug and is in contact with the side wall surface of the silicon wafer, and the polished surface of the silicon wafer is arranged close to one side in the downloading disc;

the download placing frame is positioned below the download disc and is provided with a through hole penetrated by the download overflow hole.

Further, the drive washing mechanism includes:

the drive disc is integrally connected with the uploading temporary storage mechanism and the downloading temporary storage mechanism;

the liquid through pipe is arranged on the driving disc and is respectively arranged towards the uploading temporary storage mechanism and the downloading temporary storage mechanism;

and a drive disposed below said drive disc;

the driving device drives the driving disc to drive the uploading temporary storage mechanism and the downloading temporary storage mechanism to rotate in the same direction; and synchronously controlling the liquid through pipe to spray the non-polishing surface of the silicon wafer placed in the uploading temporary storage mechanism or the downloading temporary storage mechanism.

Furthermore, the driving disc is also provided with a plurality of placing frames which are integrally arranged and extend outwards, and the placing frames are arranged along the periphery of the driving disc and are used for placing the uploading temporary storage mechanism and the downloading temporary storage mechanism.

Compared with the prior art, the temporary storage system designed by the invention can synchronously carry out temporary storage and download temporary storage on a plurality of groups of silicon wafers, not only can satisfy the stable storage of the silicon wafers, but also can ensure that the surface to be polished of the carried silicon wafer is completely infiltrated, is beneficial to removing impurities on the polished surface of the silicon wafer, prevents the surface to be polished from adsorbing impurities in the air, and simultaneously protects the non-polished surface of the carried silicon wafer.

The polishing surface of the downloaded silicon wafer is completely isolated from air in a water liquid environment, the surface of the polished surface is protected from being polluted or oxidized by particles, the polishing quality of the silicon wafer is ensured, and meanwhile, the polishing liquid and impurities on the non-polished surface of the downloaded silicon wafer are cleaned and removed.

The system can enable the silicon wafers to be continuously transferred and temporarily stored in uploading, polishing and downloading processes, energy waste is avoided, the linkage of the uploading temporary storage device, the downloading temporary storage device and the polishing process is improved, the polishing quality is guaranteed, and the polishing efficiency is improved.

Drawings

FIG. 1 is a schematic structural diagram of a temporary storage system for polishing a silicon wafer according to an embodiment of the present invention;

FIG. 2 is a top view of a temporary storage system for polishing a silicon wafer in accordance with one embodiment of the present invention;

FIG. 3 is a top view of an upload buffer mechanism according to an embodiment of the present invention;

fig. 4 is a top view of an uploading mobile station of an embodiment of the invention;

fig. 5 is a plan view of an elastic pad in an upper tray according to an embodiment of the present invention;

FIG. 6 is a top view of the distribution of the upper overflow holes in the upper tray according to an embodiment of the present invention;

FIG. 7 is a top view of a download staging mechanism according to an embodiment of the present invention;

FIG. 8 is a schematic diagram of a download buffering mechanism according to an embodiment of the present invention;

FIG. 9 is a top view of a load tray in accordance with an embodiment of the present invention;

fig. 10 is a schematic structural diagram of a download rack according to an embodiment of the present invention;

FIG. 11 is a top view of a drive purge mechanism according to an embodiment of the present invention;

FIG. 12 is a top view of a drive disk of an embodiment of the present invention.

In the figure:

10. upload temporary storage mechanism 11, upload support assembly 111 and upload column

112. Upload mobile station 12, upload overflow unit 121, and upload tray

122. Elastic pad 1221, brush 1222, brush set

123. Upload overflow hole 20, download temporary storage mechanism 21, download placing assembly

211. A download tray 2111, an inner layer slot 2112 and an outer layer slot

2113. Lug 2114, groove 212, download overflow aperture

22. Download supporting assembly 221, download column 222 and download placing rack

2221. Annular frame 2222, T-shaped frame 30, drive wiper mechanism

31. Driving disc 311, center frame 312 and placing frame

32. Liquid passing tube 33, driving device 40 and silicon wafer

Detailed Description

The invention is described in detail below with reference to the figures and specific embodiments.

The embodiment provides a temporary storage system for silicon wafer polishing, as shown in fig. 1 and fig. 2, comprising an uploading temporary storage mechanism 10 for placing a silicon wafer 40 to be polished, a downloading temporary storage mechanism 20 for placing a polished silicon wafer 40, and a driving cleaning mechanism 30 for driving the uploading temporary storage mechanism 10 and the downloading temporary storage mechanism 20 to rotate and spray the non-polished surface of the silicon wafer 40 placed in the uploading temporary storage mechanism 10 or the downloading temporary storage mechanism 20, wherein the uploading temporary storage mechanism 10 and the downloading temporary storage mechanism 20 are arranged around the driving cleaning mechanism 30. The uploading temporary storage mechanism 10 can enable the surface to be polished of the silicon wafer 40 to be completely covered and infiltrated by the aqueous solution, so that the polishing of the polished surface of the silicon wafer 40 in the next step is facilitated, impurity particles on the surface can be polished quickly and accurately, meanwhile, the surface to be polished can be isolated from air, the surface to be polished is prevented from being oxidized by the air, and the polishing effect is poor when the oxidized silicon wafer 40 is polished. The temporary storage mechanism 20 is downloaded to enable the polished surface of the silicon wafer 40 to be placed in the aqueous solution, protected by the aqueous solution and capable of being cleaned by the aqueous solution to remove polished particles and polishing liquid adhered to the surface of the silicon wafer, and meanwhile, the silicon wafer 40 completely surrounded by the aqueous solution is isolated from air, so that the polished surface can be kept moist, meanwhile, the polished surface can be prevented from being polluted by impurities, and the surface quality of the polished surface of the silicon wafer is guaranteed. The uploading temporary storage mechanism 10 and the downloading temporary storage mechanism 20 which are arranged around the driving cleaning mechanism 30 can synchronously operate a plurality of groups of silicon wafers, so that the time of the middle operation step is saved, the operation space is fully utilized, the linkage of the equipment is improved, and the polishing efficiency is improved.

Specifically, as shown in fig. 3, the upload temporary storage mechanism 10 includes several upload devices disposed adjacently, and in the present embodiment, two sets of upload devices disposed on the same side are provided, each having: an upper loading support assembly 11 for supporting the silicon wafer 40 and an upper loading overflow assembly 12 for wetting the surface of the silicon wafer 40 to be polished. The upper loading support assembly 11 is in contact with the side wall of the silicon wafer 40 and enables the silicon wafer 40 to be arranged above the upper loading overflow assembly 12 in a suspended mode, the upper loading support assembly 11 can move up and down along the height direction of the upper loading support assembly 11, the upper loading overflow assembly 12 is arranged in the upper loading support assembly 11 and is arranged concentrically with the upper loading support assembly 11, and the upper loading overflow assembly 12 is in full contact with the surface, to be polished, of the silicon wafer 40. Specifically, the initial position of the upper loading support assembly 11 is located at the upper limit position, that is, the upper end surface of the upper loading support assembly and the silicon wafer 40 is higher than the uppermost end of the lower loading overflow assembly 12, when the upper loading manipulator takes the silicon wafer 40 out of the wafer basket loaded with the silicon wafer 40 to be polished and places the silicon wafer on the upper loading support assembly 11, the upper loading support assembly 11 is controlled to descend so that the surface of the silicon wafer 40 to be polished is in full contact with the aqueous solution in the upper loading overflow assembly 12, and the surface of the silicon wafer 40 to be polished is completely isolated from the air; after the silicon wafer 40 is moved out by the polishing robot, the upper loading support assembly 11 returns to the initial position again to wait for the next silicon wafer 40 to be polished. The loading robot is a common structure in the art, and the drawings are omitted.

Further, the uploading support assembly 11 includes a plurality of vertically arranged uploading columns 111 and an uploading mobile station 112 for fixing and driving the uploading columns 111 to ascend and descend. The upper loading column 111 is arranged along the outer periphery of an upper loading tray 121 in the upper loading overflow assembly 11, the upper loading column 111 and the upper loading tray 121 are arranged in a clinging manner and can freely lift up and down vertically, and a graph obtained by connecting the upper loading column 111 is inscribed in a diameter circle of the silicon wafer 40.

The number of the upper posts 111 is at least three and is uniformly arranged on the upper moving stage 112, in this embodiment, the number of the upper posts 111 is six, and the upper posts are uniformly and symmetrically arranged on the edge of the upper moving stage 112, as shown in fig. 4, the upper moving stage 112 is coaxially arranged with the upper tray 121, so the center thereof is arranged in a ring structure. The upper moving stage 112 includes two concentric and integrally connected annular frames, but may have other structures as long as the upper column 111 can be stably fixed thereon. Is fixedly mounted on a mounting frame for driving the drive plate 31 in the washing mechanism 30, and is used for loading the movable table 112. The upper transfer stage 112 is located below the upper tray 121 in the upper overflow assembly 11, and there is a gap between the upper transfer stage and the upper tray 121, so that there is enough space for the lifting and lowering adjustment of the upper column 111.

Further, the upper loading column 111 is of a T-shaped structure, the lower end surface of the upper loading column is uniformly arranged along the circumference of the upper loading moving table 112, the upper end surface of the upper loading column is provided with an arc-shaped boss, and the side wall surface of the silicon wafer 40 is in contact with the arc-shaped boss, so that the side wall surface of the silicon wafer 40 is arranged in a suspended manner by the upper loading column 111, the contact between the upper loading column 111 and the surface to be polished of the silicon wafer 40 is zero, the contact area between the upper loading overflow hole 123 below the surface to be polished of the silicon wafer 40 and the upper loading overflow hole 123 can be maximized, and the silicon wafer 40 can. The surface quality of the polishing solution is ensured, and meanwhile, the surface to be polished can be ensured to be in full contact with the elastic pad 122 containing water liquid arranged in the loading overflow assembly 12, so that the surface to be polished can be ensured to be soaked in a full-coverage manner.

While the silicon wafer 40 is placed on the upper loading column 111, the cleaning mechanism 30 is driven to spray the liquid onto the non-polishing surface of the silicon wafer 40, i.e., the upper end surface of the silicon wafer 40, through the liquid passing tube 32 at once until the silicon wafer 40 is picked up by the polishing robot and removed from the upper loading buffer mechanism 10. This operation is intended to ensure that the upper end surface of the silicon wafer 40 is wetted with the water solution, and the water solution sprays the silicon wafer 40 to keep the silicon wafer 40 wet, thereby isolating the lower end surface of the silicon wafer 40, i.e., the surface to be polished, from the air.

Further, in the polishing machine, the polishing manipulator is a sucker type polishing manipulator which can move 360 degrees in the horizontal direction and can vertically and vertically move in a telescopic manner, the lower end face of the polishing manipulator is the same as the area of the polished silicon wafer 40, the number of the polishing manipulators is determined according to the number of the silicon wafers 40 placed in the uploading temporary storage mechanism 10 and the downloading temporary storage mechanism 20, the polishing manipulators synchronously and independently operate, and can synchronously rotate and move to be right above the uploading temporary storage mechanism 10 and the downloading temporary storage mechanism 20 so as to take out or place the silicon wafers 40, the structure is an automatic adsorption structure commonly used in the field, and the attached drawings are omitted.

Further, the height of the upper loading column 111 is greater than the overall height of the upper loading overflow assembly 11, so as to ensure that the silicon wafer 40 is suspended and set to have a sufficient height for adjusting the contact position between the silicon wafer 40 and the elastic pad 122, ensure the infiltration effect, and prevent the upper loading overflow assembly 12 from interfering with the operation of the upper and lower loading manipulators when the silicon wafer 40 is placed on the upper and lower loading manipulators.

Further, the upload support assembly 11 further includes an upload drive source for driving the movement of the upload mobile station 112, and the upload drive source is located directly below the upload mobile station 112 and is disposed coaxially with the upload tray 121. Each uploading device is provided with an independent uploading driving source, and the purpose is to ensure the stability and consistency of the overall operation of the uploading device.

Further, the upper overflow assembly 12 includes an upper tray 121 fixed on the upper support assembly 11, an elastic pad 122 disposed on the upper tray 121 and capable of freely sucking and discharging the solution, and an upper overflow hole 123 sequentially penetrating through the upper tray 121 and the elastic pad 122. Wherein, a plurality of annular brushes 1221 are arranged on one side of the elastic pad 122 away from the loading disc 121, and the loading overflow holes 123 are distributed in the gap between the brushes 1221. Preferably, the elastic pad 122 is a sponge that can absorb or discharge a solution, not only does not damage the surface of the silicon wafer 40, but also has the characteristics of rapid water absorption and recovery of the original shape after compression, can be continuously and repeatedly used, and does not contaminate the surface of the silicon wafer 40.

As shown in fig. 5, the elastic pad 122 includes at least two brush groups 1222 formed by ring-shaped brushes, and an annular gap channel is provided between adjacent brush groups 1222, which not only can be used to fix the elastic pad 122 on the loading tray 121 through a connecting member, but also can store the collection of the loaded aqueous solution, i.e. when a silicon wafer is placed on the elastic pad 122, the brush group 1222 composed of ring-shaped brushes 1221 integrally supports the silicon wafer 40, when the silicon wafer is taken by the polishing robot, the brush group 1222 is deformed by the pressure and drainage due to the instant pressure absorption of the polishing robot, and the drained aqueous solution can flow into the gap channel; after the silicon wafer 40 is removed, the brush set 1222 absorbs the water in the gap channel and the water overflowed from the upper overflow hole 123, and returns to the original state again to wait for the temporary storage of the next group of silicon wafers 40.

Further, the number of the ring-shaped brushes 1221 in the brush group 1222 disposed inside is not less than the number of the ring-shaped brushes 1221 in the brush group 1222 disposed inside. This is because the silicon plate 40 has a larger area and thus a larger pressure on the outer set 1222 than the inner set 1222, so the supporting force for the inner set 1222 is less than the outer set 1222, i.e. the number of annular brush 1221 layers in the outer set 1222 is greater. Of course, the diameter of the outer annular brush 1221 is larger, and the number of the brush heads distributed thereon is also larger, so that the brush heads can be distributed up and down in parallel or in a crossed and staggered manner, which is within the protection scope of the present application. The number of the brush groups 1222 is at least two, in this embodiment, four brush groups 1222 are selected, or other numbers of brush groups 1222 may be selected, but a gap must be formed between adjacent brush groups 1222, so as to fix the elastic pad 122, prevent water from accumulating on the elastic pad 122, and increase the contact point of the elastic pad 122 to the silicon wafer 40, so as to improve the stability of the placement and support of the silicon wafer 40.

As shown in FIG. 6, at least the center of the loading tray 121 is provided with an upper overflow hole 123 to ensure that the liquid overflows from the center of the loading tray and to enable the liquid to be radially flushed from the center of the silicon wafer 40 to the periphery. And other uploading overflow holes 123 are distributed along the center of the uploading disc 121 in a multi-layer radiation diffusion way towards the side far away from the center. The graph formed by the uploading overflow holes 123 which are distributed in a multi-layer radiation way along the center of the uploading disc 121 to the side far away from the center is a plurality of concentric circles; and the upper loading overflow holes 123 are uniformly distributed along the circumference of the circle on which the upper loading overflow holes are positioned. Since the circular area from the center to the outer diameter is gradually enlarged, the area of the liquid flow to be overflowed is increased, and more upper overflow holes 123 need to be distributed on the concentric circle at the outer side to complete the overall coverage of the surface to be polished of the silicon wafer 40. From the center to the outer diameter edge, the upper loading overflow hole 123 forms a liquid spraying assembly 30 with a concentric circle 32 structure which expands layer by layer, so that liquid flow sprayed out of the upper loading overflow hole 123 is completely radiated to all positions of the surface to be polished of the silicon wafer 40, the surface to be polished of the silicon wafer 40 is ensured to be isolated from air, and the surface to be polished of the silicon wafer 40 is prevented from being oxidized.

When the elastic pad 122 contacts the aqueous solution, the surface to be polished of the silicon wafer 40 is completely covered by the liquid flow overflowing from the upper overflow hole 123, so that the surface to be polished of the silicon wafer 40 is fully infiltrated, and the polishing and the removal of particle impurities on the surface to be polished of the silicon wafer 40 in the next step are facilitated; meanwhile, the surface to be polished of the silicon wafer 40 surrounded by the liquid flow is also isolated from the outside air, so that the surface to be polished of the silicon wafer 40 is prevented from being oxidized, and the surface quality of the polished silicon wafer 40 is ensured.

Preferably, in the present embodiment, all the upper overflow holes 123 have the same structure, and may be circular, triangular, or polygonal, so as to make all the liquid streams ejected from the upper overflow holes 123 have the same speed and size, so as to ensure the uniformity and consistency of the surface to be polished of the silicon wafer 40, which is protected and wetted by the liquid streams.

The uploading temporary storage mechanism in the embodiment is mainly used for temporarily storing the silicon wafers to be polished taken out of the wafer basket before polishing, is prepared for synchronously and independently polishing a plurality of groups of silicon wafers at the same time in the next step, can stably place the plurality of groups of silicon wafers, ensures that the polished surfaces of all the silicon wafers are completely soaked and not exposed in the air, prevents impurities in the air adsorbed by the polished surfaces from being polluted or oxidized, and simultaneously protects the non-polished surfaces of the uploaded silicon wafers. The mechanism is beneficial to removing the polished surface of the silicon wafer, simple in structure and easy to control, and enables a plurality of groups of silicon wafers to continuously and accurately flow, temporarily store, avoid energy waste, improve placing efficiency, reduce circulation placing errors and improve linkage matched with upstream and downstream processes.

At the time of the uploading process, the uploading columns 111 on both uploading devices are at their initial upper limit positions; when the loading and unloading manipulator takes the silicon wafer 40 to be polished out of the wafer basket loaded with the silicon wafer 40 and respectively places the silicon wafer 40 on the loading columns 111 of the two loading devices, the circular arc-shaped bosses of the loading columns 111 are contacted with the side wall surfaces of the silicon wafer 40, the silicon wafer 40 is suspended and arranged in a hanging manner, and the polishing surfaces of the silicon wafer 40 are all arranged downwards; simultaneously, the cleaning mechanism 30 is driven to spray liquid to the non-polishing surfaces of the two silicon wafers 40 through the liquid through pipe 32, and two uploading driving sources in the two uploading devices are synchronously controlled to synchronously overflow the water liquid through the uploading overflow holes 123. After the two silicon wafers 40 are placed, the two uploading driving sources are controlled to control the uploading columns 111 of the two uploading devices to synchronously descend to the lower limit position, and the surfaces to be polished of the two silicon wafers 40 are in full contact with the elastic pads 122. And controlling the two polishing manipulators to be respectively arranged right above the two uploading devices, enabling the two polishing manipulators to synchronously descend to adsorb the silicon wafer 40, and synchronously moving the uploading devices out to the polishing mechanism for polishing. After the silicon chip 40 is removed, the water storage and liquid spraying work of the upper overflow hole 123 and the liquid through pipe 32 is stopped; and the upper post 111 returns to the original position again to wait for the next round of the placement of the silicon wafer 40 to be polished.

As shown in fig. 7 and 8, the download register mechanism 20 includes a plurality of download devices disposed adjacent to each other, and the number of download devices in the download register mechanism 20 is the same as the number of upload devices in the upload register mechanism 10, and the download devices are disposed around the drive cleaning mechanism 30. The download devices each have: a down-loading placing assembly 21 for storing a certain solution and making the solution flow in a buffer manner and a down-loading supporting assembly 22 for supporting the polished silicon wafer 40 and moving up and down. Wherein the solution in the lower loading module 21 can be completely contacted with the polished surface of the silicon wafer 40; the downloading supporting component 22 is arranged through the downloading placing component 21; the circumscribed circle of the figure formed by the contact points of the connecting download supporting assembly 22 and the silicon wafer 40 has the same diameter as the silicon wafer 40. That is, the polished silicon wafer 40 is placed in the lower loading assembly 21 which only contains water liquid, the polished surface of the silicon wafer 40 is placed downwards, and the liquid passing pipe 32 in the cleaning mechanism 30 is driven to continuously pass through the non-polished surface at the upper end of the silicon wafer 40; then the silicon wafer 40 is supported by the controlled download supporting component 22 to be separated from the water level in the download placing component 21, and then the silicon wafer 40 is moved into the empty wafer basket to be collected.

Specifically, the download placing assembly 21 includes a download tray 211 carrying water liquid and a download overflow hole 212 at least disposed at the center of the download tray 211, wherein the download tray 211 is a dual-layer structure and is fixedly disposed on the download supporting assembly 22 and coaxially disposed with the download supporting assembly 22. The download tray 211 has an inner tank 2111 for storing aqueous solution and an outer tank 2112 which is contoured to the inner tank 2111 and integrally connected to the inner tank 2111, the inner tank 2111 being of circular configuration as shown at 9. A plurality of lugs 2113 are provided in the outer slot 2112 for the lower support assembly 22 to pass through and be integrally provided with the outer slot 2112. The arrangement of the download overflow holes 212 is beneficial to improving the flow of water in the download tray 211, and meanwhile, water can be continuously supplied to the inner layer slot 2111. Preferably, a down-loading overflow hole 212 is further disposed on one side of the inner groove 2111 near the outer sidewall, so that the entire surface of the polishing surface of the cover silicon wafer 40 can be cleaned by water flow, and the polishing surface can be completely disposed in a water environment and isolated from the outside air, and the impurity particles in the air can be attached to the polishing surface to prevent contamination.

Further, the height of the connection layer between the outer layer slot 2112 and the inner layer slot 2111 is lower than the height of the outer wall of the outer layer slot 2112, so as to facilitate the lifting of the silicon wafer 40 supported by the downloading pillars 221 in the downloading supporting assembly 22. The upper end face of the outer wall surface of the outer layer slot 2112 is provided with a plurality of grooves 2114, all the grooves 2114 are uniformly arranged, and the grooves 2114 are all arranged on the outer layer slot 2112 between the adjacent lugs 2113. The grooves 2114 are provided to overflow the water in the inner grooves 2111, so as to prevent the silicon wafer 40 from being ejected due to excessive water in the inner grooves 2111.

Further, the download support assembly 21 comprises a plurality of download posts 221 disposed along the periphery of the outer layer slot 2111 and a download holder 222 for holding the download posts 221, wherein the upper section of the download posts 221 is a cone, passes through the lugs 2113 and contacts the side wall surface of the silicon wafer 40, and the polished surface of the silicon wafer 40 is disposed near one side of the download tray 211. The download placing rack 222 is located below the download tray 211 and is provided with a through hole through which the download overflow hole 123 passes, and is connected to the lower end surface of the download column 221.

Preferably, the lower section of the down loading column 221 is a cylinder, and the upper section thereof is a cone, which is more favorable for the matching of the side wall surface of the silicon wafer 40 and the contact thereof; the height of the upper section cone is smaller than that of the lower section column, so that the stability of placing the silicon wafer 40 is better facilitated; preferably, the included angle of the generatrix of the upper section is not more than 45 °, so that the side wall surface of the silicon wafer 40 is raised by the upper loading column 111 and suspended, so that the downward polishing surface of the silicon wafer 40 is in zero contact with the lower loading column 221, and on the premise that the water contact between the silicon wafer 40 and the inner-layer groove 2111 is not affected, the lower loading column 221 is more favorable for pushing the silicon wafer 40 to be separated from the lower loading device, and meanwhile, the silicon wafer 40 can be stably placed on the lower loading column 221.

In the initial position, the lower load column 221 is at the lowest position and the upper end surface of the connection layer between the inner slot 2111 and the outer slot 2112 is flush, so as to ensure that the polished surface of the silicon wafer 40 suspended on the lower load column 221 is completely exposed to the water in the inner slot 2111. After the cleaning is finished, the downloading column 221 is controlled to push the silicon wafers 40 to vertically move upwards to the highest position, after the loading and unloading manipulator moves the silicon wafers away, the downloading column 221 returns to the initial position again, and the next group of silicon wafers 40 is waited to be placed.

As shown in fig. 10, the download rack 222 includes a central annular shelf 2221 and a T-shaped shelf 2222 extending outward and integrally provided with the annular shelf 2221, the annular shelf 2221 is penetrated by a download overflow hole 212 provided at the center of the download tray 211; the end of the T-shaped frame 2222 remote from the annular frame 2221 is connected to the adjacent downloader column 221.

Further, the download supporting assembly 22 further comprises a download driving source for driving the download rack 222 to drive the download column 221 to move up and down along the height direction of the lug 2113, and the download driving source is disposed below the download rack 222 and is coaxial with the download rack 222. The download temporary storage mechanism in the embodiment can stably and synchronously temporarily store a plurality of groups of polished silicon wafers taken out of the polishing machine, ensure that the polishing surfaces of the downloaded silicon wafers are completely in a water liquid environment to keep moist, simultaneously ensure that the polished surfaces are not contacted with air, protect the polished surfaces from being polluted or oxidized, ensure the polishing quality of the silicon wafers, and simultaneously clean and remove polishing liquid and impurities on the non-polished surfaces of the downloaded silicon wafers; the silicon wafer surface quality protection device has the advantages that the structural design is simple, the linkage is good, the surface quality of the silicon wafer is protected, the silicon wafer can be stably, accurately and continuously flowed and temporarily stored in the downloading process, the energy waste is avoided, and the working efficiency is high.

During the downloading process, the downloading devices are all placed right below the polishing manipulator, and the downloading columns 221 are all at their initial positions; the polishing manipulator drives the silicon wafer 40 to move downwards into the downloading disc 211 and is supported and placed by the downloading column 221, and simultaneously controls the downloading overflow holes 212 in the two downloading devices and the two liquid through pipes 32 driving the cleaning mechanism 30 to face the downloading devices to synchronously overflow and spray towards the lower end face and the upper end face of the silicon wafer 40 respectively; after the polishing manipulator is moved away, the driving disc 31 in the driving cleaning mechanism 30 is controlled to rotate, the two downloading devices are driven to rotate to the positions close to the empty wafer baskets for collecting the blanking silicon wafers 40, the two silicon wafers 40 are put into the wafer baskets one by one through the loading and unloading manipulator, and after the silicon wafers 40 are moved away, the downloading columns 221 return to the initial positions. Repeating the above steps, and continuing to temporarily store the next group of silicon wafers 40.

As shown in fig. 11, the driving and cleaning mechanism 30 includes a driving plate 31 integrally connected to the upload buffer mechanism 10 and the download buffer mechanism 20, a plurality of liquid passing pipes 32 disposed on the driving plate 31 and respectively facing the upload buffer mechanism 10 and the download buffer mechanism 20, and a driving device 33 disposed below the driving plate 31. The driving device 33 drives and controls the driving disc 31 to drive the uploading temporary storage mechanism 10 and the downloading temporary storage mechanism 20 to rotate in the same direction; and synchronously controlling the liquid pipe 32 to spray the non-polishing surface of the silicon wafer 40 placed in the upper temporary storage mechanism 10 or the lower temporary storage mechanism 20.

In the present embodiment, the uploading driving source and the downloading driving source may employ a control manner such as hydraulic, piston, or pneumatic to control the ascending and descending movement of the uploading column 111 and the downloading column 221, which is not particularly limited herein. The driving device 33 is a commonly used motor control structure, which is a device commonly used in the field and will not be described in detail herein; of course, other control methods are also adopted and are within the protection scope of the present application.

In the present embodiment, the number of the liquid passing tubes 32 is six, and the liquid passing tubes 32 are respectively directed to two uploading devices in the uploading temporary storage mechanism 10 and two downloading devices in the downloading temporary storage mechanism 20, that is, when the silicon wafer 40 is placed on the uploading tray 121 or the downloading tray 211, the liquid passing tubes 32 are controlled to spray the non-polishing surface of the silicon wafer 40 for cleaning impurities or polishing liquid on the silicon wafer 40; meanwhile, the surface to be polished or the non-polished surface of the silicon wafer 40 is kept in a wet state, which is beneficial to the next polishing and cleaning work; the surface to be polished or polished of the silicon wafer 40 can be protected from air, and the surface quality of the silicon wafer 40 can be protected.

As shown in fig. 12, the driving disc 31 includes a circular center frame 311, a plurality of placing frames 312 integrally disposed and extending outward are further disposed on the outer periphery of the center frame, the driving device 33 is fixedly mounted on the lower end of the center frame 311, the placing frames 312 are disposed along the periphery of the center frame 311 through a connecting member and are used for placing the upload temporary storage mechanisms 10 and the download temporary storage mechanisms 20, and the number of the placing frames 312 is the same as that of the upload discs 121 and the download discs 211.

1. The temporary storage system can synchronously carry out uploading temporary storage and downloading temporary storage on a plurality of groups of silicon wafers, not only can meet the requirement of stable storage of the silicon wafers, but also can ensure that the surface to be polished of the uploaded silicon wafers is completely infiltrated, is beneficial to removing impurities on the polished surface of the silicon wafers, prevents the surface to be polished from adsorbing impurities in the air, and simultaneously protects the non-polished surface of the uploaded silicon wafers.

2. The polishing surface of the downloaded silicon wafer is completely isolated from air in a water liquid environment, the surface of the polished surface is protected from being polluted or oxidized by particles, the polishing quality of the silicon wafer is ensured, and meanwhile, the polishing liquid and impurities on the non-polished surface of the downloaded silicon wafer are cleaned and removed.

3. The system can enable the silicon wafers to be continuously transferred and temporarily stored in uploading, polishing and downloading processes, energy waste is avoided, the linkage of the uploading temporary storage device, the downloading temporary storage device and the polishing process is improved, the polishing quality is guaranteed, and the polishing efficiency is improved.

The embodiments of the present invention have been described in detail, and the description is only for the preferred embodiments of the present invention and should not be construed as limiting the scope of the present invention. All equivalent changes and modifications made within the scope of the present invention shall fall within the scope of the present invention.

Claims

1. A temporary storage system for polishing silicon wafers is characterized by comprising:

2. A temporary storage system for silicon wafer polishing as set forth in claim 1 wherein said upload temporary storage mechanism comprises a plurality of adjacent upload devices, said upload devices having:

an upper loading support assembly for supporting the silicon wafer;

3. A temporary storage system for silicon wafer polishing as set forth in claim 2 wherein said upper load support assembly comprises:

a plurality of uploading columns;

4. A temporary storage system for silicon wafer polishing as set forth in claim 2 or 3 wherein said upload overflow assembly comprises:

the loading disc is fixedly arranged on the loading support assembly;

the upper loading overflow holes are distributed in the hairbrush gap.

5. A temporary storage system for silicon wafer polishing as set forth in claim 4 wherein said upper overflow hole is provided at least at the center of said upper tray.

6. A temporary storage system for silicon wafer polishing as set forth in any one of claims 1-3 and 5 wherein said download temporary storage mechanism comprises a plurality of adjacently disposed download units, said download units having:

7. The temporary storage system for silicon wafer polishing as set forth in claim 6 wherein said download placement assembly comprises:

a download tray;

8. The temporary storage system for silicon wafer polishing as set forth in claim 7 wherein said download support assembly comprises:

the downloading placing rack is used for fixing the downloading columns;

9. A temporary storage system for silicon wafer polishing as set forth in any one of claims 1-3, 5, 7-8 wherein said drive cleaning mechanism comprises:

and a drive disposed below said drive disc;

10. A temporary storage system for silicon wafer polishing as claimed in claim 9, wherein said drive plate further has a plurality of integrally disposed and outwardly extending storage racks, said storage racks being disposed along the periphery of said drive plate and being used for placing said upper temporary storage mechanism and said lower temporary storage mechanism.