A grinding apparatus

Abstract

This disclosure provides a grinding apparatus, comprising: a lower fixed plate, including a working plate surface and a bottom surface disposed opposite to each other; the working plate surface is provided with guide grooves distributed in a mesh pattern, and guide holes penetrating the working plate surface and the bottom surface are provided at several intersection nodes of the guide grooves; a transfer and recycling unit, including a transfer component with a chamber and a recycling container; the guide holes are connected to the chamber of the transfer component, and the chamber of the recycling container is connected to the chamber of the transfer component; and a negative pressure generating unit, connected to the recycling container, for providing a negative pressure environment for the inner cavity of the recycling container, so that residues in the guide grooves flow into the chamber of the transfer component through the guide holes. This grinding apparatus can effectively clean the grinding plate surface and improve the quality of the ground products.

Description

Technical Field

[0001] This invention relates to the field of semiconductor processing technology, and more particularly to a grinding apparatus. Background Technology

[0002] In the semiconductor wafer manufacturing industry, silicon wafers are the most commonly used semiconductor material, an indispensable component in chip production, and the material that accounts for the highest cost. With the rapid development of chip technology and photovoltaic technology, the demand for silicon wafers has increased dramatically.

[0003] Lamination (LAP) is an important process in silicon wafer manufacturing. The purpose of lamination is to give the silicon wafer a flat surface with a certain geometrical accuracy, while removing the mechanical stress damage layer on the surface of the silicon wafer caused by cutting during the slicing process.

[0004] Double-sided grinding involves placing a cut silicon wafer between upper and lower grinding discs. During the rotation of the grinding discs, the surface of the silicon wafer is roughened and thinned by the action of the grinding fluid and pressure.

[0005] However, during the grinding process, grinding waste such as slurry residue will remain in the guide groove of the lower platen of the grinding equipment. If the residence time is too long, the slurry will solidify and reduce its fluidity, which will cause blockage of the guide groove, resulting in grinding debris, deterioration of flatness, and deterioration of wafer quality.

[0006] Currently, the cleaning method for guide channels involves scraping off the solidified residue with a blade after grinding is complete. Since the cleaning process must be carried out after grinding, if cleaning is not done promptly, the residue will solidify, making blade cleaning time-consuming and laborious, and the residue is difficult to remove, resulting in unsatisfactory cleaning results. Summary of the Invention

[0007] This disclosure provides a grinding apparatus that can effectively clean the grinding disc surface and improve the quality of the ground products.

[0008] The technical solutions provided in this disclosure are as follows:

[0009] A grinding apparatus, comprising:

[0010] The lower plate includes a working plate surface and a bottom surface arranged opposite to each other. The working plate surface is provided with guide grooves distributed in a mesh pattern, and guide holes penetrating the working plate surface and the bottom surface are provided at several intersection nodes of the guide grooves.

[0011] A transfer and recycling unit includes a transfer component with a chamber and a recycling container, wherein the flow guide hole is connected to the chamber of the transfer component, and the chamber of the recycling container is connected to the chamber of the transfer component;

[0012] A negative pressure generating unit, connected to the recycling container, is used to provide a negative pressure environment for the inner cavity of the recycling container, so that the residue in the guide groove flows into the cavity of the transfer component through the guide hole.

[0013] For example, the transfer and recycling unit further includes a conversion wheel and multiple connecting conduits; wherein, the conversion wheel is located below the bottom surface and can rotate synchronously with the lower fixed plate; the conversion wheel is provided with through holes penetrating the two axially opposite sides of the conversion wheel, the through holes corresponding one-to-one with the guide holes and connected through the corresponding connecting conduits; the conversion wheel is rotatable relative to the transfer component, the chamber of the transfer component is located below the conversion wheel, and the top of the chamber of the transfer component is provided with an opening to collect all the residue flowing out of the through holes.

[0014] For example, the transfer component includes: a body adapted to the shape of the conversion wheel, the body being hollow to form a cavity of the transfer component, the opening of the cavity abutting the bottom of the conversion wheel so that the cavity communicates with all the through holes.

[0015] For example, the transfer component further includes a rotating assembly disposed between the transfer wheel and the main body, so that the transfer wheel is rotatable relative to the main body.

[0016] For example, the body extends upward along the opening edge of the chamber to form an extension, the extension being located on the outer periphery of the conversion wheel, and the rotating assembly includes a bearing assembly located between the conversion wheel and the extension.

[0017] For example, the flow-guiding trench includes a plurality of trench intersection nodes arranged in an array, and the flow-guiding holes are located at the trench intersection nodes that are spaced apart.

[0018] For example, in a plurality of trench intersection nodes distributed in an array, a flow guide hole is provided at every other trench intersection node in the same row; and a flow guide hole is provided at every other trench intersection node in the same column.

[0019] For example, the diameter of the guide hole gradually decreases along the direction from the working plate surface to the bottom surface.

[0020] For example, the inner diameter of the guide hole is larger than the width of the guide groove.

[0021] For example, the grinding apparatus further includes:

[0022] The main shaft, wherein the lower fixed plate and the conversion wheel are coaxially mounted on the main shaft;

[0023] The sun gear is located above the working disk surface and is mounted on the spindle;

[0024] An annular internal gear is arranged circumferentially along the working disk surface and has a gap with the sun gear;

[0025] Planetary gears are located above the working disk surface and in the gap, and mesh with the sun gear and the annular internal gear;

[0026] The support disk is located on the planetary tooth.

[0027] The beneficial effects of the embodiments disclosed herein are as follows:

[0028] In the above scheme, a mesh-like distribution of guide grooves is provided on the working surface of the lower platen, and guide holes are provided at several intersection nodes of the guide grooves. The guide holes can be connected to the chamber of the transfer and recycling unit. The negative pressure generating unit can generate a negative pressure environment in the chamber of the transfer and recycling unit, and then transmit the negative pressure to the guide holes. The negative pressure can absorb the residue in the guide grooves, clean the slurry residue and grinding waste in the guide grooves of the lower platen in real time, avoid accumulation and blockage, improve the cleaning efficiency of grinding residue, reduce the grinding fragment rate, and improve the wafer grinding quality. Attached Figure Description

[0029] Figure 1 This diagram illustrates the structure of the grinding equipment provided in the embodiments of this disclosure.

[0030] Figure 2 This diagram illustrates the working surface of the lower platen in the grinding apparatus provided in this embodiment. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this disclosure. All other embodiments obtained by those skilled in the art based on the described embodiments of this disclosure without creative effort are within the scope of protection of this disclosure.

[0032] Unless otherwise defined, the technical or scientific terms used in this disclosure shall have the ordinary meaning understood by one of ordinary skill in the art to which this disclosure pertains. The terms “first,” “second,” and similar terms used in this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, the terms “an,” “a,” or “the,” and similar terms do not indicate a quantity limitation, but rather indicate the presence of at least one. The terms “including,” “comprising,” or “containing,” and similar terms mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. The terms “connected,” “linked,” or similar terms are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. The terms “upper,” “lower,” “left,” and “right,” etc., are used only to indicate relative positional relationships, and these relative positional relationships may change accordingly when the absolute position of the described objects changes.

[0033] like Figure 1 and Figure 2 As shown in the present invention, a grinding device is provided, including a lower platen 100, a transfer and recycling unit 200, and a negative pressure generating unit 300.

[0034] The lower plate 100 includes a working plate surface 100A and a bottom surface 100B arranged opposite to each other. The working plate surface 100A is provided with a mesh-like distribution of guide grooves 110. In other words, the guide grooves 110 can be formed by multiple grooves intersecting to form a mesh. At several groove intersection nodes a of the guide grooves 110, there are guide holes 120 that penetrate the working plate surface 100A and the bottom surface 100B.

[0035] The transfer and recycling unit 200 includes a transfer component 210 with a chamber and a recycling container 220. The guide hole 120 is connected to the chamber of the transfer component 210, and the chamber of the recycling container 220 is connected to the chamber of the transfer component 210.

[0036] The negative pressure generating unit 300 is connected to the recycling container 220 and is used to provide a negative pressure environment for the inner cavity of the recycling container 220 so that the residue in the guide channel 110 flows into the cavity of the transfer component 210 through the guide hole 120.

[0037] In the above scheme, a mesh-like distribution of guide grooves 110 is provided on the working surface 100A of the lower fixed plate 100. The guide grooves 110 are mesh-like, and guide holes 120 are provided at several groove intersection nodes a of the guide grooves 110. The guide holes 120 can be connected to the chamber of the transfer and recycling unit 200. The negative pressure generating unit 300 can generate a negative pressure environment in the chamber of the transfer and recycling unit 200, and then transmit the negative pressure to the guide holes 120.

[0038] During the grinding process, grinding residues and waste can be guided through the flow channel 110 and absorbed into the chamber of the transfer component 210 by the negative pressure at the flow hole 120, and then recycled by the recycling container 220. In this way, the slurry residues and grinding wastes in the flow channel 110 of the lower platen 100 can be cleaned in real time, avoiding accumulation and blockage, improving the efficiency of grinding residue cleaning, reducing the grinding fragmentation rate, and improving the quality of wafer grinding.

[0039] In some exemplary embodiments, such as Figure 1 and Figure 2 As shown, the grinding equipment further includes a spindle 400, a sun gear 500, a planetary gear 600, an annular internal gear 700, and a support plate. The lower fixed plate 100 is mounted on the spindle 400. The sun gear 500 is located above the working plate surface 100A and is mounted on the spindle 400. The annular internal gear 700 is arranged circumferentially along the working plate surface 100A and has a gap with the sun gear 500. The planetary gear 600 is located above the working plate surface 100A, within the gap, and meshes with the sun gear 500 and the annular internal gear 700. The support plate is located on the planetary gear 600.

[0040] During grinding, the workpiece to be ground can be placed on the bearing plate. When the spindle 400 rotates, it can drive the lower fixed plate 100 and the sun tooth 500 to rotate, driving the bearing plate on the planetary tooth 600 to revolve around the sun tooth 500 and rotate around its own axis, so as to grind the workpiece to be ground.

[0041] The double-sided grinding equipment may also include an upper fixed plate, which is arranged opposite to the lower fixed plate 100. During the double-sided process, the workpiece to be ground comes into contact with the surfaces of the upper and lower fixed plates 100. It undergoes cycloidal motion through the rotation of the sun gear 500 and the ring internal gear 700. By supplying grinding slurry, mechanical and chemical reactions occur on the grinding surface, as well as physical reactions caused by rotation and pressure, so as to achieve the purpose of grinding the silicon wafer surface.

[0042] In this embodiment, the grinding slurry can be supplied through a nozzle installed on the upper plate.

[0043] In some exemplary embodiments, each bearing disk includes multiple workpiece bearing disk holes, and one workpiece to be ground can be placed in each workpiece bearing disk hole. Therefore, multiple workpieces to be ground can be ground simultaneously.

[0044] In this embodiment, the workpiece to be ground can be a silicon wafer.

[0045] Since the lower fixed plate 100 rotates during grinding, the guide holes 120 provided on the lower fixed plate 100 are displaced as the lower fixed plate 100 rotates. In order to smoothly draw out the residue from the guide holes 120 under negative pressure and guide it into the recycling container 220, in some exemplary embodiments, such as... Figure 1 and Figure 2 As shown, the transfer and recycling unit 200 also includes a conversion wheel 230 and multiple connecting conduits 240;

[0046] The conversion wheel 230 is located below the bottom surface 100B and can rotate synchronously with the lower fixed plate 100;

[0047] The conversion wheel 230 is provided with through holes 231 that pass through two opposite sides of the axial direction of the conversion wheel 230. The through holes 231 correspond one-to-one with the guide holes 120 and are connected through the corresponding connecting conduits 240.

[0048] The conversion wheel 230 is rotatable relative to the transfer member 210. The chamber of the transfer member 210 is located below the conversion wheel 230, and the top of the chamber of the transfer member 210 is provided with an opening to collect all the residue flowing out of the through hole 231.

[0049] By adopting the above solution, the conversion wheel 230 is set, and the through hole 231 on the conversion wheel 230 and the guide hole 120 on the lower fixed plate 100 are connected one-to-one through the connecting conduit 240. In this way, the residue in the guide hole 120 of the lower fixed plate 100 can be smoothly guided into the through hole 231 of the conversion wheel 230, and the lower fixed plate 100 and the conversion wheel 230 can rotate synchronously. For example, the conversion wheel 230 can be coaxially connected to the main shaft 400 with the lower fixed plate 100 to achieve the purpose of synchronous rotation of the two. This setting can avoid the connecting conduit 240 from getting tangled together.

[0050] Furthermore, the transfer component 210 is provided below the conversion wheel 230, and the conversion wheel 230 is rotatable relative to the transfer component 210. In this way, the transfer component 210 can remain stationary when the conversion wheel 230 rotates, so as to smoothly communicate with the recycling container 220 and ensure that the grinding residue is smoothly extracted into the recycling container 220.

[0051] In addition, the top of the chamber of the transfer component 210 is provided with an opening, which can hold all the residue flowing out of the through hole 231. Through the above ingenious design, the residue in the guide hole 120 on the rotating lower plate 100 can be smoothly guided into the chamber of the transfer component 210.

[0052] In some exemplary embodiments, such as Figure 1 and Figure 2 As shown, the transfer component 210 includes: a main body 211 adapted to the shape of the conversion wheel 230, the main body 211 being hollow to form a cavity of the transfer component 210, the opening of the cavity being aligned with the bottom of the conversion wheel 230 so that the cavity communicates with all the through holes 231.

[0053] It should be noted that the opening of the chamber is aligned with the bottom of the conversion wheel 230, specifically meaning that the opening area of ​​the chamber can at least cover all the through holes 231.

[0054] For example, the opening edge of the chamber may be arranged around the bottom peripheral edge of the conversion wheel 230 to ensure that the chamber can hold the residue discharged from all the through holes 231.

[0055] It should also be noted that the shape of the main body 211 is adapted to that of the conversion wheel 230. Specifically, for example, if the conversion wheel 230 is in the shape of a disc, then the main body 211 can be a hollow disc or hollow cylinder or other structure that has the same shape and size as the conversion wheel 230.

[0056] In some exemplary embodiments, such as Figure 1 and Figure 2 As shown, the transfer component 210 further includes a rotating assembly 250, which is disposed between the conversion wheel 230 and the main body 211 so that the conversion wheel 230 can rotate relative to the main body 211.

[0057] By adopting the above solution, the rotating component 250 can be rotatably connected between the converting wheel 230 and the main body 211 by setting the rotating component 250 between the converting wheel 230 and the main body 211.

[0058] In some exemplary embodiments, such as Figure 1 and Figure 2 As shown, the main body 211 extends upward along the opening edge of the chamber to form an extension 212, the extension 212 is located on the outer periphery of the conversion wheel 230, and the rotating assembly 250 includes a bearing assembly, the bearing assembly being located between the conversion wheel 230 and the extension 212.

[0059] Using the above scheme, the main body 211 extends upward from the opening edge of the chamber to form an extension 212. The extension 212 may be arranged around the outer circumference of the conversion wheel 230, or it may be located only at several points on the outer periphery of the conversion wheel 230. The extension 212 may be constructed as a track, cage, and support structure of the bearing assembly. By setting the bearing assembly between the extension 212 and the conversion wheel 230, smooth relative rotation between the conversion wheel 230 and the extension 212 can be achieved.

[0060] For example, the bearing assembly may include, but is not limited to, any suitable bearing component such as rolling bearings, sliding bearings, or combined bearings that combine rolling bearings and sliding bearings.

[0061] Furthermore, in some exemplary embodiments, such as Figure 1 and Figure 2 As shown, the flow guiding groove 110 includes a plurality of groove intersection nodes a arranged in an array, and the flow guiding holes 120 are located at the groove intersection nodes a that are spaced apart. That is, any two adjacent flow guiding holes 120 can be separated by at least one groove intersection node a.

[0062] This ensures that grinding residue can be guided through the flow channel 110 and drawn away by the negative pressure of the flow hole 120, while minimizing the number of flow holes 120 to reduce damage to the silicon wafer during the grinding process due to the negative pressure.

[0063] Specifically, in some exemplary embodiments, such as Figure 1 and Figure 2As shown, in a plurality of trench intersection nodes a arranged in an array, a guide hole 120 is provided at every other trench intersection node a in the same row; and a guide hole 120 is provided at every other trench intersection node a in the same column. Thus, by further optimizing the number and position of the guide holes 120, it is possible to ensure that grinding residue can be guided through the guide trenches 110 and drawn away by the negative pressure of the guide holes 120, while simultaneously reducing the number of guide holes 120 to minimize damage to the silicon wafer during the grinding process due to the negative pressure.

[0064] Furthermore, it should be noted that in some exemplary embodiments of this disclosure, the polishing equipment may also include a control unit, which may be communicatively connected to the negative pressure generating unit 300. The control unit may be used to control the working state of the negative pressure generating unit 300, which may include power level, etc., in order to control the negative pressure level for absorbing polishing residue, so as to avoid damage to the silicon wafer during the polishing process.

[0065] Furthermore, in some exemplary embodiments, such as Figure 1 and Figure 2 As shown, the diameter of the guide hole 120 gradually decreases along the direction from the working surface 100A to the bottom surface 100B. For example, the guide hole 120 may be funnel-shaped along the direction from the working surface 100A to the bottom surface 100B to further avoid clogging and improve the cleaning effect of grinding residue.

[0066] It is understood that the construction of the guide hole 120 is not limited to this. For example, the guide hole 120 may be a straight through hole of equal diameter; or, the guide hole 120 may also include an inlet located on the working plate surface 100A and an outlet located on the bottom surface 100B, with only a section of the hole near the inlet constructed in a funnel shape, and a straight through hole section of equal diameter existing between the inlet and the outlet.

[0067] Furthermore, in some exemplary embodiments, such as Figure 1 and Figure 2 As shown, the inner diameter of the guide hole 120 is larger than the width of the guide groove 110. This makes it easier to draw the grinding residue guided in the guide groove 110 into the guide hole 120.

[0068] Specifically, the width of the guide groove 110 can be 2 to 3 mm, for example, 2.1 mm, 2.2 mm, 2.3 mm, 2.4 mm, 2.5 mm, 2.6 mm, 2.7 mm, 2.8 mm, 2.9 mm or 3 mm.

[0069] The inner diameter of the guide hole 120 can be 1-2 mm larger than the width of the guide groove 110. For example, the inner diameter of the guide hole 120 can be 3.1 mm, 3.2 mm, 3.3 mm, 3.4 mm, 3.5 mm, 3.6 mm, 3.7 mm, 3.8 mm, 3.9 mm, 4 mm, 4.1 mm, 4.2 mm, 4.3 mm, 4.4 mm, 4.5 mm, 4.6 mm, 4.7 mm, 4.8 mm, 4.9 mm, or 5 mm.

[0070] Furthermore, in some exemplary embodiments, the negative pressure generating unit 300 may include, but is not limited to, a vacuum pump.

[0071] The following points need to be explained:

[0072] (1) The accompanying drawings of the embodiments of this disclosure only involve the structures involved in the embodiments of this disclosure. Other structures can be referred to the general design.

[0073] (2) For clarity, the thickness of layers or regions is enlarged or reduced in the drawings used to describe embodiments of the present disclosure, i.e., these drawings are not drawn to actual scale. It will be understood that when an element such as a layer, film, region or substrate is referred to as being “above” or “below” another element, the element may be “directly” located “above” or “below” the other element or there may be intermediate elements.

[0074] (3) Where there is no conflict, the embodiments of this disclosure and the features in the embodiments can be combined with each other to obtain new embodiments.

[0075] The above are merely specific embodiments of this disclosure, but the scope of protection of this disclosure is not limited thereto. The scope of protection of this disclosure shall be determined by the scope of the claims.

Claims

1. A grinding device, characterized in that, include: The lower plate includes a working plate surface and a bottom surface arranged opposite to each other. The working plate surface is provided with guide grooves distributed in a mesh pattern, and guide holes penetrating the working plate surface and the bottom surface are provided at several intersection nodes of the guide grooves. A transfer and recycling unit includes a transfer component with a chamber and a recycling container, wherein the flow guide hole is connected to the chamber of the transfer component, and the chamber of the recycling container is connected to the chamber of the transfer component; and A negative pressure generating unit, connected to the recycling container, is used to provide a negative pressure environment for the inner cavity of the recycling container, so that the residue in the guide groove flows into the cavity of the transfer component through the guide hole; The transfer and recycling unit further includes a conversion wheel and multiple connecting conduits; wherein, the conversion wheel is located below the bottom surface and can rotate synchronously with the lower fixed plate; the conversion wheel has through holes penetrating two opposite sides of the axial direction of the conversion wheel, the through holes corresponding one-to-one with the guide holes and connected through the corresponding connecting conduits; the conversion wheel is rotatable relative to the transfer component, the chamber of the transfer component is located below the conversion wheel, and the top of the chamber of the transfer component has an opening to collect all the residue flowing out of the through holes; the transfer component includes: and The document describes a main body with a shape adapted to the conversion wheel, and a rotating assembly disposed between the conversion wheel and the main body to allow the conversion wheel to rotate relative to the main body. The main body is hollow to form a chamber for the transfer component, and the opening of the chamber aligns with the bottom of the conversion wheel to communicate with all the through holes. The main body extends upward along the edge of the opening of the chamber to form an extension located on the outer periphery of the conversion wheel. The rotating assembly includes a bearing assembly located between the conversion wheel and the extension.

2. The grinding equipment according to claim 1, characterized in that, The flow-guiding trench includes multiple trench intersection nodes arranged in an array, and the flow-guiding holes are located at the trench intersection nodes that are spaced apart.

3. The grinding equipment according to claim 1, characterized in that, In a plurality of trench intersection nodes arranged in an array, a guide hole is provided at every other trench intersection node in the same row; and a guide hole is provided at every other trench intersection node in the same column.

4. The grinding equipment according to claim 1, characterized in that, The diameter of the guide hole gradually decreases along the direction from the working plate surface to the bottom surface.

5. The grinding equipment according to claim 1, characterized in that, The inner diameter of the guide hole is greater than the width of the guide groove.

6. The grinding equipment according to claim 1, characterized in that, The grinding equipment also includes: The main shaft, wherein the lower fixed plate and the conversion wheel are coaxially mounted on the main shaft; The sun gear is located above the working disk surface and is mounted on the spindle; An annular internal gear is arranged circumferentially along the working disk surface and has a gap with the sun gear; The planetary gear is located above the working disk surface and in the gap, and meshes with the sun gear and the annular internal gear; The support disk is located on the planetary tooth.

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