Method of cleaning crystalline particles generated in a sapphire silica polishing process

Abstract

The application relates to the field of sapphire optics, and discloses a method for cleaning crystalline particles generated in a sapphire silicon dioxide polishing process. The method comprises the following steps: (1) cleaning the upper and lower polishing disc surfaces of a polishing device I; the cleaning I conditions comprise: using a four-section program to uniformly accelerate the brush disc; (2) cleaning the liquid cylinder of the polishing device II by using a water gun, cleaning the liquid pipe of the polishing device III, and cleaning the liquid pipe and the inside of the lower polishing disc of the polishing device IV; the liquid inlet and outlet of the liquid pipe are provided with a filtering device. The method provided by the application can clean the crystalline particles in the polishing device in time, quickly and completely, thereby prolonging the service life of the polishing device, reducing the downtime of the polishing device and improving the first-time product processing yield.

Description

Technical Field

[0001] This invention relates to the field of sapphire optics, and more specifically, to a method for cleaning crystalline particles generated during the polishing process of sapphire silicon dioxide. Background Technology

[0002] Currently, the polishing processes used in the polishing of sapphire optical double polished wafers are generally divided into two types: silicon dioxide (SiO2) polishing and aluminum oxide (Al2O3) polishing. However, during processing, especially when using silicon dioxide (SiO2) polishing, a large number of crystal blocks and particles are generated. Furthermore, when the polishing equipment is used for a long time, a thick layer of solidified crystal blocks will adhere to the inside of the polishing equipment, which is difficult to clean. Even if it can be cleaned, it requires a lot of time and manpower, delaying the normal processing of the polishing equipment.

[0003] If the attached solidified crystals are not cleaned in a timely and effective manner, they will block the circulation of the inlet and outlet liquid ports, leading to risks such as liquid interruption on the plate, high plate temperature, and explosion of the polishing device. In severe cases, it may even damage the polishing device.

[0004] Therefore, timely, rapid and thorough cleaning of solidified crystalline particles after polishing is extremely important, and plays a vital role in stabilizing polishing equipment processing, extending the service life of polishing equipment, reducing downtime of polishing equipment, and improving product yield. Summary of the Invention

[0005] The purpose of this invention is to provide a method for timely, rapid and thorough cleaning of crystalline particles generated during the polishing process of sapphire silicon dioxide, so as to extend the service life of the polishing equipment, reduce the downtime of the polishing equipment, and improve the first-pass yield of the product.

[0006] To achieve the above objectives, the present invention provides a method for cleaning crystalline particles generated during the polishing process of sapphire silicon dioxide, the method comprising:

[0007] (1) Clean the surfaces of the upper and lower polishing discs of the polishing device I; the conditions for cleaning I include: using a four-stage program to uniformly increase the speed of the brush disc, with a starting speed of 4-6 rpm and an ending speed of 25-30 rpm, and a speed-to-pressure ratio of 1:8-15.

[0008] (2) After cleaning the liquid cylinder of the polishing device with a water gun (II), the liquid pipe of the polishing device (III) is cleaned, and then the liquid pipe and the interior of the lower polishing disc of the polishing device (IV) are cleaned; the inlet and outlet of the liquid pipe are equipped with a filter device.

[0009] The conditions for cleaning III include: using a water circulation method;

[0010] The conditions for cleaning IV include: using an alkaline liquid circulation method, wherein the temperature of the alkaline liquid is 35-45℃ and the pH value is 12.5-13.5.

[0011] Preferably, in step (1), the speed increase of the four-segment program uniform speed-increasing brush is 4-12 rpm / segment, and the ratio of the speed value of each segment to the speed increase value is an integer.

[0012] In a preferred embodiment, in step (1), the brushing time of the four-segment program uniform speed-up brushing is 12-18 min / segment, and the speed change time is 15-30 s.

[0013] Preferably, in step (1), the device for brushing the brush is a brush wheel.

[0014] Preferably, in step (2), the water circulation time is 8-15 min and the flow rate is 12-16 mL / min.

[0015] In a preferred embodiment, in step (2), the solute in the alkaline liquid is selected from at least one of potassium hydroxide, sodium hydroxide, and lithium hydroxide.

[0016] Preferably, in step (2), during the cleaning of the interior of the lower polishing disc of the polishing device, the rotation speed of the upper and lower polishing discs is 3-30 rpm and the time is 3-20 h.

[0017] In a preferred embodiment, in step (2), the absolute value of the difference in rotational speed between the upper and lower polishing discs is ≤15, and the rotational speed ratio between the upper and lower polishing discs is 1:1-3.

[0018] According to a preferred embodiment, in step (2), the filtration device is selected from one of filter stockings, filter screens, filter cotton, and filter cartridges.

[0019] According to another preferred embodiment, in step (2), the pressure of the water gun is 6-8 MPa.

[0020] This invention employs a four-stage uniform speed-increasing brushing process and utilizes the built-in pump of the liquid cylinder in the polishing device to sequentially circulate water and hot alkaline liquid, in conjunction with the upper and lower polishing discs in the polishing device, to effectively clean the crystalline particles inside the polishing device. This prevents crystallization blockage in the liquid pipes inside the polishing device, ultimately extending the service life of the polishing device, reducing scratches on the product, and improving the first-pass yield of the product. Detailed Implementation

[0021] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0022] As mentioned above, this invention provides a method for cleaning crystalline particles generated during the polishing process of sapphire silicon dioxide, the method comprising:

[0023] (1) Clean the surfaces of the upper and lower polishing discs of the polishing device I; the conditions for cleaning I include: using a four-stage program to uniformly increase the speed of the brush disc, with a starting speed of 4-6 rpm and an ending speed of 25-30 rpm, and a speed-to-pressure ratio of 1:8-15.

[0024] (2) After cleaning the liquid cylinder of the polishing device with a water gun (II), the liquid pipe of the polishing device (III) is cleaned, and then the liquid pipe and the interior of the lower polishing disc of the polishing device (IV) are cleaned; the inlet and outlet of the liquid pipe are equipped with a filter device.

[0025] The conditions for cleaning III include: using a water circulation method;

[0026] The conditions for cleaning IV include: using an alkaline liquid circulation method, wherein the temperature of the alkaline liquid is 35-45℃ and the pH value is 12.5-13.5.

[0027] Preferably, in step (1), the speed increase of the four-segment program uniform speed-increasing brush is 4-12 rpm / segment, and the ratio of the rotational speed value to the speed increase value in each segment is an integer. The inventors of this invention have found that, in this preferred case, the polishing device has a longer service life and the first-pass yield of the obtained products is higher.

[0028] In a preferred embodiment, in step (1), the brushing time of the four-segment program uniform speed-up brushing is 12-18 min / segment, and the speed change time is 15-30 s.

[0029] Preferably, in step (1), the device for brushing the brush is a brush wheel. For example, the brush wheel can be a brush wheel with a wire diameter of 0.6 mm and a bristle height of 7 mm.

[0030] More preferably, in step (1), the device for brushing the brush is a brush wheel, and the number of brush wheels is 5-8.

[0031] Preferably, in step (2), the water circulation time is 8-15 min and the flow rate is 12-16 mL / min. The inventors of this invention have found that, under this preferred condition, the first-pass yield of the obtained product is higher.

[0032] In a preferred embodiment, in step (2), the solute in the alkaline liquid is selected from at least one of potassium hydroxide, sodium hydroxide, and lithium hydroxide. More preferably, in step (2), the solute in the alkaline liquid is potassium hydroxide. The inventors of this invention have discovered that, in this preferred embodiment, the polishing device has a longer service life.

[0033] Preferably, in step (2), during the cleaning of the interior of the lower polishing disc of the polishing device IV, the rotation speed of the upper and lower polishing discs is 3-30 rpm, and the time is 3-20 h. More preferably, in step (2), during the cleaning of the interior of the lower polishing disc of the polishing device IV, the rotation speed of the upper and lower polishing discs is 3-20 rpm, and the time is 3-10 h.

[0034] In a preferred embodiment, in step (2), the absolute value of the speed difference between the upper and lower polishing discs is ≤15, and the speed ratio between the upper and lower polishing discs is 1:1-3. The inventors of this invention have found that, under this preferred embodiment, the first-pass yield of the obtained product is higher.

[0035] According to a preferred embodiment, in step (2), the filtering device is selected from a filter stock, a filter screen, filter cotton, and a filter cartridge. According to a particularly preferred embodiment, in step (2), the filtering device is a filter stock.

[0036] According to another preferred embodiment, in step (2), the pressure of the water gun is 6-8 MPa.

[0037] The present invention will be described in detail below through examples.

[0038] In the following examples, unless otherwise specified, all raw materials used are commercially available.

[0039] Example 1

[0040] (1) Clean the surfaces of the upper and lower polishing discs of the polishing device;

[0041] The conditions for cleaning I are: using a four-segment program with uniform speed increase for the polishing discs, wherein the upper and lower polishing discs rotate at the same speed, and

[0042] First stage of brushing: Start the upper and lower polishing discs, increase the speed to 5 rpm at a constant speed, with a pressure of 70 kg and a time of 30 s;

[0043] Second stage of brushing: uniformly increase speed to 10 rpm, pressure is 100 kg, time is 30 s;

[0044] Third stage of brushing: uniformly increase speed to 15 rpm, pressure is 150 kg, time is 30 s;

[0045] Fourth stage brushing: uniformly increase speed to 25 rpm, pressure to 200 kg, time to 15 min;

[0046] (2) After cleaning the liquid cylinder of the polishing device with a water gun at a pressure of 7MPa (II), the liquid pipe of the polishing device (III) is cleaned, and then the liquid pipe and the interior of the lower polishing disc of the polishing device (IV) are cleaned; the inlet and outlet of the liquid pipe are equipped with filter socks (filtration devices).

[0047] The conditions for cleaning III are: water circulation is used, the time is 10 minutes, and the flow rate is 15 mL / min;

[0048] The conditions for cleaning IV are as follows: potassium hydroxide solution (alkaline liquid) is circulated, and the temperature of the potassium hydroxide solution is 40°C, and the pH value is 13.5; and

[0049] The upper polishing disc rotates at 3 rpm, the lower polishing disc rotates at 3 rpm, and the time is 3 hours.

[0050] Example 2

[0051] (1) Clean the surfaces of the upper and lower polishing discs of the polishing device;

[0052] The conditions for cleaning I are: using a four-segment program with uniform speed increase for the polishing discs, wherein the upper and lower polishing discs rotate at the same speed, and

[0053] First stage of brushing: Start the upper and lower polishing discs, increase the speed to 5 rpm at a constant speed, with a pressure of 70 kg and a time of 30 s;

[0054] Second stage of brushing: uniformly increase speed to 10 rpm, pressure is 100 kg, time is 30 s;

[0055] Third stage of brushing: uniformly increase speed to 15 rpm, pressure is 150 kg, time is 30 s;

[0056] Fourth stage brushing: uniformly increase speed to 25 rpm, pressure to 200 kg, time to 15 min;

[0057] (2) After cleaning the liquid cylinder of the polishing device with a water gun at a pressure of 7MPa (II), the liquid pipe of the polishing device (III) is cleaned, and then the liquid pipe and the interior of the lower polishing disc of the polishing device (IV) are cleaned; the inlet and outlet of the liquid pipe are equipped with filter socks (filtration devices).

[0058] The conditions for cleaning III are as follows: water circulation is used; the time is 10 minutes; and the flow rate is 30 mL / min.

[0059] The conditions for cleaning IV are as follows: potassium hydroxide solution (alkaline liquid) is circulated, and the temperature of the potassium hydroxide solution is 40°C, and the pH value is 13.5; and

[0060] The upper polishing disc rotates at 3 rpm, the lower polishing disc rotates at 3 rpm, and the time is 3 hours.

[0061] Example 3

[0062] (1) Clean the surfaces of the upper and lower polishing discs of the polishing device;

[0063] The conditions for cleaning I are: using a four-segment program with uniform speed increase for the polishing discs, wherein the upper and lower polishing discs rotate at the same speed, and

[0064] First stage of brushing: Start the upper and lower polishing discs, increase the speed to 5 rpm at a constant speed, with a pressure of 70 kg and a time of 30 s;

[0065] Second stage of brushing: uniformly increase speed to 10 rpm, pressure is 100 kg, time is 30 s;

[0066] Third stage of brushing: uniformly increase speed to 15 rpm, pressure is 150 kg, time is 30 s;

[0067] Fourth stage brushing: uniformly increase speed to 25 rpm, pressure to 200 kg, time to 15 min;

[0068] (2) After cleaning the liquid cylinder of the polishing device with a water gun at a pressure of 7MPa (II), the liquid pipe of the polishing device (III) is cleaned, and then the liquid pipe and the interior of the lower polishing disc of the polishing device (IV) are cleaned; the inlet and outlet of the liquid pipe are equipped with filter socks (filtration devices).

[0069] The conditions for cleaning III are as follows: water circulation is used; the time is 10 minutes and the flow rate is 15 mL / min;

[0070] The conditions for cleaning IV are as follows: a sodium hydroxide solution (alkaline liquid) is circulated, and the sodium hydroxide solution is at a temperature of 40°C and a pH of 13.5; and

[0071] The upper polishing disc rotates at 3 rpm, the lower polishing disc rotates at 3 rpm, and the time is 3 hours.

[0072] Example 4

[0073] (1) Clean the surfaces of the upper and lower polishing discs of the polishing device;

[0074] The conditions for cleaning I are: using a four-segment program with uniform speed increase for the polishing discs, wherein the upper and lower polishing discs rotate at the same speed, and

[0075] First stage of brushing: Start the upper and lower polishing discs, increase the speed to 5 rpm at a constant speed, with a pressure of 70 kg and a time of 30 s;

[0076] Second stage of brushing: uniformly increase speed to 10 rpm, pressure is 100 kg, time is 30 s;

[0077] Third stage of brushing: uniformly increase speed to 15 rpm, pressure is 150 kg, time is 30 s;

[0078] Fourth stage brushing: uniformly increase speed to 25 rpm, pressure to 200 kg, time to 15 min;

[0079] (2) After cleaning the liquid cylinder of the polishing device with a water gun at a pressure of 7MPa (II), the liquid pipe of the polishing device (III) is cleaned, and then the liquid pipe and the interior of the lower polishing disc of the polishing device (IV) are cleaned; the inlet and outlet of the liquid pipe are equipped with filter socks (filtration devices).

[0080] The conditions for cleaning III are as follows: water circulation is used; the time is 10 minutes and the flow rate is 15 mL / min;

[0081] The conditions for cleaning IV are as follows: potassium hydroxide solution (alkaline liquid) is circulated, and the temperature of the potassium hydroxide solution is 40°C, and the pH value is 13.5; and

[0082] The upper polishing disc rotates at 5 rpm, the lower polishing disc rotates at 20 rpm, and the time is 3 hours.

[0083] Example 5

[0084] (1) Clean the surfaces of the upper and lower polishing discs of the polishing device;

[0085] The conditions for cleaning I are: using a four-segment program with uniform speed increase for the polishing discs, wherein the upper and lower polishing discs rotate at the same speed, and

[0086] First stage of brushing: Start the upper and lower polishing discs, increase the speed to 5 rpm at a constant speed, with a pressure of 70 kg and a time of 30 s;

[0087] Second stage of brushing: uniformly increase speed to 15 rpm, pressure is 150 kg, time is 30 s;

[0088] Third stage of brushing: uniformly increase speed to 19 rpm, pressure is 170 kg, time is 30 s;

[0089] Fourth stage brushing: uniformly increase speed to 25 rpm, pressure to 200 kg, time to 15 min;

[0090] (2) After cleaning the liquid cylinder of the polishing device with a water gun at a pressure of 7MPa (II), the liquid pipe of the polishing device (III) is cleaned, and then the liquid pipe and the interior of the lower polishing disc of the polishing device (IV) are cleaned; the inlet and outlet of the liquid pipe are equipped with filter socks (filtration devices).

[0091] The conditions for cleaning III are as follows: water circulation is used; the time is 10 minutes and the flow rate is 15 mL / min;

[0092] The conditions for cleaning IV are as follows: potassium hydroxide solution (alkaline liquid) is circulated, and the temperature of the potassium hydroxide solution is 40°C, and the pH value is 13.5; and

[0093] The upper polishing disc rotates at 3 rpm, the lower polishing disc rotates at 3 rpm, and the time is 3 hours.

[0094] Comparative Example 1

[0095] (1) Clean the surfaces of the upper and lower polishing discs of the polishing device;

[0096] The conditions for cleaning I are: a two-stage program with uniform speed increase of the polishing discs is used, wherein the upper and lower polishing discs rotate at the same speed, and

[0097] First stage of brushing: Start the upper and lower polishing discs, increase the speed uniformly to 10 rpm, the pressure is 100 kg, and the time is 30 s;

[0098] Second stage of brushing: uniformly increase speed to 25 rpm, pressure to 200 kg, time to 15 min;

[0099] (2) After cleaning the liquid cylinder of the polishing device with a water gun at a pressure of 7MPa (II), the liquid pipe of the polishing device (III) is cleaned, and then the liquid pipe and the interior of the lower polishing disc of the polishing device (IV) are cleaned; the inlet and outlet of the liquid pipe are equipped with filter socks (filtration devices).

[0100] The conditions for cleaning III are as follows: water circulation is used; the time is 10 minutes and the flow rate is 15 mL / min;

[0101] The conditions for cleaning IV are as follows: potassium hydroxide solution (alkaline liquid) is circulated, and the temperature of the potassium hydroxide solution is 40°C, and the pH value is 13.5; and

[0102] The upper polishing disc rotates at 3 rpm, the lower polishing disc rotates at 3 rpm, and the time is 3 hours.

[0103] Comparative Example 2

[0104] (1) Clean the surfaces of the upper and lower polishing discs of the polishing device;

[0105] The conditions for cleaning I are: using a four-segment program with uniform speed increase for the polishing discs, wherein the upper and lower polishing discs rotate at the same speed, and

[0106] First stage of brushing: Start the upper and lower polishing discs, increase the speed to 5 rpm at a constant speed, with a pressure of 70 kg and a time of 30 s;

[0107] Second stage of brushing: uniformly increase speed to 15 rpm, pressure is 150 kg, time is 30 s;

[0108] Third stage of brushing: uniformly increase speed to 25 rpm, pressure to 200 kg, time to 30 s;

[0109] Fourth stage brushing: uniformly increase speed to 35 rpm, pressure to 280 kg, time to 15 min;

[0110] (2) After cleaning the liquid cylinder of the polishing device with a water gun at a pressure of 7MPa (II), the liquid pipe of the polishing device (III) is cleaned, and then the liquid pipe and the interior of the lower polishing disc of the polishing device (IV) are cleaned; the inlet and outlet of the liquid pipe are equipped with filter socks (filtration devices).

[0111] The conditions for cleaning III are as follows: water circulation is used; the time is 10 minutes and the flow rate is 15 mL / min;

[0112] The conditions for cleaning IV are as follows: potassium hydroxide solution (alkaline liquid) is circulated, and the temperature of the potassium hydroxide solution is 40°C, and the pH value is 13.5; and

[0113] The upper polishing disc rotates at 3 rpm, the lower polishing disc rotates at 3 rpm, and the time is 3 hours.

[0114] Comparative Example 3

[0115] (1) Clean the surfaces of the upper and lower polishing discs of the polishing device;

[0116] The conditions for cleaning I are: using a four-segment program with uniform speed increase for the polishing discs, wherein the upper and lower polishing discs rotate at the same speed, and

[0117] First stage of brushing: Start the upper and lower polishing discs, increase the speed to 5 rpm at a constant speed, with a pressure of 70 kg and a time of 30 s;

[0118] Second stage of brushing: uniformly increase speed to 10 rpm, pressure is 100 kg, time is 30 s;

[0119] Third stage of brushing: uniformly increase speed to 15 rpm, pressure is 150 kg, time is 30 s;

[0120] Fourth stage brushing: uniformly increase speed to 25 rpm, pressure to 175 kg, time to 15 min;

[0121] (2) After cleaning the liquid cylinder of the polishing device with a water gun at a pressure of 7MPa (II), the liquid pipe of the polishing device (III) is cleaned, and then the liquid pipe and the interior of the lower polishing disc of the polishing device (IV) are cleaned; the inlet and outlet of the liquid pipe are equipped with filter socks (filtration devices).

[0122] The conditions for cleaning III are as follows: water circulation is used; the time is 10 minutes and the flow rate is 15 mL / min;

[0123] The conditions for cleaning IV are as follows: potassium hydroxide solution (alkaline liquid) is circulated, and the temperature of the potassium hydroxide solution is 40°C, and the pH value is 13.5; and

[0124] The upper polishing disc rotates at 3 rpm, the lower polishing disc rotates at 3 rpm, and the time is 3 hours.

[0125] Comparative Example 4

[0126] (1) Clean the surfaces of the upper and lower polishing discs of the polishing device;

[0127] The conditions for cleaning I are: using a four-segment program with uniform speed increase for the polishing discs, wherein the upper and lower polishing discs rotate at the same speed, and

[0128] First stage of brushing: Start the upper and lower polishing discs, increase the speed to 5 rpm at a constant speed, with a pressure of 70 kg and a time of 30 s;

[0129] Second stage of brushing: uniformly increase speed to 10 rpm, pressure is 100 kg, time is 30 s;

[0130] Third stage of brushing: uniformly increase speed to 15 rpm, pressure is 150 kg, time is 30 s;

[0131] Fourth stage brushing: uniformly increase speed to 25 rpm, pressure to 200 kg, time to 15 min;

[0132] (2) After cleaning the liquid cylinder of the polishing device with a water gun at a pressure of 7MPa (II), the liquid pipe of the polishing device (III) is cleaned, and then the liquid pipe and the interior of the lower polishing disc of the polishing device (IV) are cleaned; the inlet and outlet of the liquid pipe are equipped with filter socks (filtration devices).

[0133] The conditions for cleaning III are as follows: water circulation is used; the time is 10 minutes and the flow rate is 15 mL / min;

[0134] The conditions for cleaning IV are as follows: potassium hydroxide solution (alkaline liquid) is circulated, and the potassium hydroxide solution is at a temperature of 50°C and a pH of 13.5; and

[0135] The upper polishing disc rotates at 3 rpm, the lower polishing disc rotates at 3 rpm, and the time is 3 hours.

[0136] Comparative Example 5

[0137] (1) Clean the surfaces of the upper and lower polishing discs of the polishing device;

[0138] The conditions for cleaning I are: using a four-segment program with uniform speed increase for the polishing discs, wherein the upper and lower polishing discs rotate at the same speed, and

[0139] First stage of brushing: Start the upper and lower polishing discs, increase the speed to 5 rpm at a constant speed, with a pressure of 70 kg and a time of 30 s;

[0140] Second stage of brushing: uniformly increase speed to 10 rpm, pressure is 100 kg, time is 30 s;

[0141] Third stage of brushing: uniformly increase speed to 15 rpm, pressure is 150 kg, time is 30 s;

[0142] Fourth stage brushing: uniformly increase speed to 25 rpm, pressure to 200 kg, time to 15 min;

[0143] (2) After cleaning the liquid cylinder of the polishing device with a water gun at a pressure of 7MPa (II), the liquid pipe of the polishing device (III) is cleaned, and then the liquid pipe and the interior of the lower polishing disc of the polishing device (IV) are cleaned; the inlet and outlet of the liquid pipe are equipped with filter socks (filtration devices).

[0144] The conditions for cleaning III are as follows: water circulation is used; the time is 10 minutes and the flow rate is 15 mL / min;

[0145] The conditions for cleaning IV are as follows: potassium hydroxide solution (alkaline liquid) is circulated, and the temperature of the potassium hydroxide solution is 40°C, and the pH value is 11; and

[0146] The upper polishing disc rotates at 3 rpm, the lower polishing disc rotates at 3 rpm, and the time is 3 hours.

[0147] Test example:

[0148] The cleaning methods in the embodiments and comparative examples were tested and recorded for the indicators involved in Table 1. The following examples all take a single machine processing 900 light guide strips / run as an example, and the details are as follows:

[0149] Downtime: The total downtime of the equipment due to crystal cleaning (including the time required for manual cleaning when the machine is not completely cleaned).

[0150] Product first-pass yield: refers to the percentage of qualified products that pass cleanroom inspection after a single production run out of the total number of products processed (that is, the percentage of qualified products that do not require rework or repair out of the total number of products processed).

[0151] Table 1

[0152] Downtime (h) Number of qualified products in one run (pieces / run) Product first-pass yield (%) Example 1 3.5 892 99.1 Example 2 3.8 864 95.9 Example 3 3.6 830 92.2 Example 4 4.3 796 88.4 Example 5 4.5 859 95.4 Comparative Example 1 5.7 740 82.2 Comparative Example 2 3.6 729 81.0 Comparative Example 3 6.0 635 70.6 Comparative Example 4 3.7 715 79.4 Comparative Example 5 4.9 654 72.7

[0153] As can be seen from the results in Table 1, the method provided by this invention can clean the crystalline particles in the polishing device in a timely, rapid and thorough manner, which can extend the service life of the polishing device and improve the first-pass yield of the product. At the same time, compared with the existing manual methods for cleaning crystals, it can significantly reduce the downtime of the polishing device caused by cleaning crystals, thereby greatly improving production efficiency.

[0154] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A method for cleaning crystalline particles generated during the polishing process of sapphire silica, characterized in that, The method includes: (1) Clean the surfaces of the upper and lower polishing discs of the polishing device. The conditions for cleaning I include: using a four-segment program uniform speed-increasing brush disc, with a starting speed of 4-6 rpm and an ending speed of 25-30 rpm, and a speed-to-pressure ratio of 1:8-15; the speed-increasing amplitude of the four-segment program uniform speed-increasing brush disc is 4-12 rpm / segment, and the ratio of the speed value to the speed-increasing amplitude value of each segment is an integer. (2) After cleaning the liquid cylinder of the polishing device with a water gun (II), the liquid pipe of the polishing device (III) is cleaned, and then the liquid pipe and the interior of the lower polishing disc of the polishing device (IV) are cleaned; the inlet and outlet of the liquid pipe are equipped with a filter device. The conditions for cleaning III include: using a water circulation method; The conditions for cleaning IV include: using an alkaline liquid circulation method, wherein the temperature of the alkaline liquid is 35-45℃ and the pH value is 12.5-13.

5.

2. The method according to claim 1, wherein, In step (1), the brushing time of the four-segment program uniform speed-up brushing is 12-18 min / segment, and the speed change time is 15-30 s.

3. The method according to claim 1, wherein, In step (1), the device for brushing the brush is a brush wheel.

4. The method according to claim 1, wherein, In step (2), the water circulation time is 8-15 min and the flow rate is 12-16 mL / min.

5. The method according to claim 1, wherein, In step (2), the solute in the alkaline liquid is selected from at least one of potassium hydroxide, sodium hydroxide, and lithium hydroxide.

6. The method according to claim 1, wherein, In step (2), the interior of the lower polishing disc of the polishing device is cleaned. In step IV, the rotation speed of the upper and lower polishing discs is 3-30 rpm and the time is 3-20 h.

7. The method according to claim 6, wherein, In step (2), the absolute value of the difference in rotation speed between the upper and lower polishing discs is ≤15, and the rotation speed ratio between the upper and lower polishing discs is 1:1-3.

8. The method according to claim 1, wherein, In step (2), the filtration device is selected from one of the following: filter stock, filter screen, filter cotton, and filter element.

9. The method according to claim 1, wherein, In step (2), the pressure of the water gun is 6-8 MPa.