A polishing disc for electrically assisted photocatalytic polishing of large-size diamonds

Abstract

The present invention discloses a polishing disc for electrically assisted photocatalytic polishing of large-sized diamonds, comprising a supporting disc, a contact disc, a light source, a through-hole electro-hydraulic slip ring, a power supply component and a liquid supply component. The polishing disc is a hollow polishing disc, with many through holes and multiple ring grooves on the upper surface; the light source is arranged in the middle of the polishing disc, and the light emitted by the light source irradiates the polishing surface of the diamond to be polished; the through-hole electro-hydraulic slip ring is arranged above the polishing disc, supplies power and liquid to the polishing disc and transmits motion; the liquid supply part is used to provide cooling liquid to the light source and recycle waste liquid; during the polishing process, the polishing surface of the diamond to be polished is immersed in the polishing liquid; the light emitted by the light source irradiates the surface to be polished, and at the same time, an oxidation reaction and a grinding reaction of the polishing pad on the diamond surface occur. The embodiment of the present invention can improve the material removal rate and surface quality of diamond.

Description

Technical Field

[0001] The invention relates to the technical field of semiconductor manufacturing, and in particular to a polishing disc used for electrically assisted photocatalytic polishing of large-sized diamonds. Background Art

[0002] Diamond has good mechanical properties, its friction coefficient is extremely low (0.08~0.1), its natural hardness is the highest (100GPa), and it has good wear resistance, good chemical stability, and high thermal conductivity (2×10 3 W / (m·K)), large resistance (>10 13 The application of large-sized single-crystal diamond requires that it has an ultra-smooth surface and high flatness, while the surface roughness of the original growth surface of single-crystal diamond is usually from a few hundred nanometers to several microns, which cannot be directly used in the field of semiconductor substrates or devices. Therefore, efficient grinding and polishing technology has become the premise for the industrial application of large-sized single-crystal diamond.

[0003] At present, more than 90% of electronic devices in the world use silicon. As the power of electronic devices increases, the performance of single crystal silicon determines that it cannot work in high-frequency, high-power, and high-temperature working environments. However, diamond not only has an extremely low dielectric constant, but also has a wide bandgap, high carrier mobility, high thermal conductivity, and high breakdown voltage. Diamond can be semiconductorized by doping with an appropriate amount of boron atoms, which makes it an excellent semiconductor material. For example, diamond semiconductors can work at a high temperature of 600°C, which is twice that of silicon semiconductors. The operating frequency can reach 81GHz and can be used in microwave and millimeter wave band ultra-high-speed computer chips and other fields. It is considered to be the most ideal semiconductor substrate material in the future. Single crystal diamond belongs to the fourth generation of semiconductor materials. It is not only the inherent demand and development direction of the upgrading of the semiconductor technology field, but also the electronic information material that supports the upgrading of industries characterized by intelligence and the development of high-tech industries in the future. Actively carrying out the technical accumulation of the fourth generation of semiconductor materials represented by diamond is of great forward-looking significance for achieving "innovation-driven development".

[0004] If single crystal diamond materials are to reasonably and fully demonstrate their excellent properties, mature material processing and treatment methods must be used to obtain ultra-smooth flat processing surfaces. Traditional single crystal diamond processing methods mainly include mechanical grinding, laser polishing, ion beam polishing and various composite field processing, such as chemical mechanical polishing, thermochemical polishing, etc. Mechanical grinding uses diamond grinding wheels or diamond grinding powder as grinding media, and has high processing efficiency, but the microscopic surface quality of diamond after processing is not good, and it is easy to produce defects such as micro cracks, grooves and scratches; laser polishing has high processing efficiency and can be used for the processing of complex shapes, but the polishing process is complicated, and the final surface quality of polishing is related to the initial surface roughness; ion beam polishing is suitable for the processing of complex shapes, and can achieve large-diameter local atomic-level polishing, but the polishing efficiency is low, and the polishing environment and equipment requirements are high; traditional chemical mechanical polishing uses molten salt as an oxidant to corrode the carbon atoms on the diamond surface at high temperature to generate CO and CO2 to achieve the purpose of polishing. This method has a poor processing environment and is very harmful to operators and processing equipment.

[0005] Therefore, in view of the above-mentioned technical problems, a polishing disc for electrically assisted photocatalytic polishing of large-sized diamonds is proposed. Summary of the invention

[0006] The invention provides a polishing disc for electrically assisted photocatalytic polishing of large-sized diamonds, so as to improve the diamond polishing efficiency and the surface quality of the diamond.

[0007] In a first aspect, an embodiment of the present invention provides a polishing disk for electrically assisted photocatalytic polishing of large-sized diamonds, comprising:

[0008] A support disk, wherein the support disk is a hollow structure, wherein a plurality of through holes are arranged in the support disk and a plurality of ring grooves are arranged on the upper surface thereof, wherein the through holes are used to place graphite electrodes and the ring grooves are used to place conductive rings;

[0009] A contact plate is provided with a plurality of circles of through holes evenly arranged on the contact plate, and the positions of the through holes correspond one to one with the supporting plate.

[0010] A conductive ring is disposed in the ring groove above the support plate and contacts the graphite electrode to form an electrical circuit;

[0011] The polishing head is arranged below the contact plate, connected to the rotating component, and performs a rotating motion. The upper surface of the polishing head is provided with a plurality of diamond placement grooves distributed in an annular manner for placing the diamonds to be polished.

[0012] The polishing pad is arranged on the surface to be polished of the diamond to be polished, and the area of ​​the polishing pad is greater than or equal to the area of ​​the surface to be polished.

[0013] A light source is arranged in the middle of the support plate; the light emitted by the light source irradiates the polishing surface of the diamond to be polished;

[0014] A liquid supply part is used to provide cooling liquid to the light source and recycle waste liquid; during the polishing process, the liquid supply part inputs external cooling liquid into the light source through the electro-hydraulic slip ring;

[0015] Optionally, the support plate and contact plate of the polishing plate, the annular groove on the support plate can be in the form of concentric circles, radial or spiral, and a suitable contact plate can be selected according to the properties of the material to be polished, and it is convenient to replace it in the later stage due to wear;

[0016] Optionally, the polishing disc can achieve a rotation speed of 100-1000 rpm without a drive, and can achieve a rotation speed of 1000-3000 rpm if the polishing disc is mounted on a spindle;

[0017] Optionally, the light source includes but is not limited to a UV ultraviolet curing lamp, a mercury lamp ultraviolet light source, a short arc xenon lamp, a high-intensity metal halide lamp, and the like.

[0018] And / or, the coolant is water;

[0019] Among them, during the polishing process, polishing liquid is dripped into the polishing pad, and at the same time, the polishing pad and the polishing disk grind the polishing surface of the diamond to be polished at the same time; at the same time, under the irradiation of the light source, the polishing liquid and the polishing surface of the diamond to be polished undergo an oxidation reaction, thereby realizing the polishing process.

[0020] Optionally, the polishing disc for electrically assisted photocatalytic polishing of large-sized diamonds further comprises:

[0021] A power supply, wherein the positive electrode and the negative electrode of the power supply are respectively connected to the positive electrode and the negative electrode of the upper end of the through-hole electro-hydraulic slip ring, and the positive electrode and the negative electrode of the lower end of the through-hole electro-hydraulic slip ring are respectively connected to the positive and negative electrodes of the conductive ring and the light source. Under the irradiation of the light source, free-moving electrons are generated in the polishing liquid. At the same time, an electric field is formed by connecting the conductive ring and the conductive graphite with the conductive polishing liquid to realize the polishing process.

[0022] Rotating component: connected to the polishing disc and used to control the polishing disc to rotate around its central axis.

[0023] Optionally, the polishing disc for electrically assisted photocatalytic polishing of large-sized diamonds further comprises:

[0024] A protective shell, installed above the support plate, for protecting the conductive ring and the energized parts on the support plate;

[0025] A protective cover, installed in the central hollow portion below the contact plate, for protecting the light source from contact with the polishing liquid;

[0026] a nozzle, for providing the polishing liquid to the polishing pad;

[0027] A liquid storage tank, used for storing the polishing liquid waste generated during the polishing process;

[0028] The intelligent cabinet is used to control the wavelength of the ultraviolet light source and provide the cooling liquid to the ultraviolet light source.

[0029] In a second aspect, an embodiment of the present invention further provides a method for polishing a large-size diamond by electro-assisted photocatalytic polishing, which is applied to a polishing disk for electro-assisted photocatalytic polishing of a large-size diamond provided in any embodiment of the present invention. The method for polishing a large-size diamond by electro-assisted photocatalytic polishing comprises:

[0030] Insert the diamond to be polished into the diamond placement groove on the polishing head;

[0031] Placing a polishing pad on the polishing surface of the diamond to be polished, and fixing the polishing pad;

[0032] Supplying polishing liquid into the polishing pad to fully wet the polishing pad;

[0033] Starting the power supply and turning on the ultraviolet light source, so that the ultraviolet light source irradiates the surface of the diamond to be polished, connects the circuit on the polishing disk, and forms a loop with the free mobile electrons in the polishing liquid;

[0034] The rotating spindle is started, and the polishing process begins. Under the action of chemical mechanical polishing, the polishing surface of the diamond to be polished is polished.

[0035] The polishing disc for electrically assisted photocatalytic polishing of large-sized diamonds provided in the embodiment of the present invention adopts the following principle: when nano-TiO2 is irradiated with ultraviolet light of a certain wavelength (387.5nm), the electrons in the valence band are excited to jump to the conduction band, and positively charged holes are generated in the valence band. The holes can absorb OH groups adsorbed on the surface of titanium dioxide particles. –Oxidation with H2O generates highly oxidizing hydroxyl radicals ·OH (standard redox potential is 2.76eV). Photogenerated electrons can also react with O2 to generate active oxygen radicals such as O2·, which also participate in the redox reaction. The highly oxidizing holes and hydroxyl radicals ·OH generated by titanium dioxide under photocatalytic conditions react with diamonds to achieve the purpose of atomic-level diamond removal. With the help of the mechanical movement of titanium dioxide particles and the diamond surface, the bumps are removed preferentially, which increases the contact probability of photogenerated holes and hydroxyl radicals with diamonds, accelerates the chemical reaction rate and material removal rate, and thus obtains an ultra-smooth surface.

[0036] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. By reading the following description with reference to the drawings, the above and other purposes, features and advantages of the exemplary embodiments of the present invention will become easy to understand. In the drawings, several embodiments of the present invention are shown in an exemplary and non-limiting manner, and the same or corresponding reference numerals represent the same or corresponding parts, among which:

[0038] Figure 1 Schematic diagram of the external structure of a polishing disc for electrically assisted photocatalytic polishing of large-sized diamonds provided in an embodiment of the present invention;

[0039] Figure 2 It is a schematic structural diagram of a polishing disc for electrically assisted photocatalytic polishing of large-sized diamonds provided by an embodiment of the present invention;

[0040] Figure 3 It is a schematic diagram of the cross-sectional structure of a polishing disc for electrically assisted photocatalytic polishing of large-sized diamonds provided by an embodiment of the present invention;

[0041] Figure 4 is a schematic diagram of a top view of the support plate provided by an embodiment of the present invention;

[0042] Figure 5 A schematic diagram of the structure of a contact plate provided by an embodiment of the present invention when viewed from above. DETAILED DESCRIPTION

[0043] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art. If not specifically stated, the technical means used in the embodiments are conventional means well known to those skilled in the art.

[0044] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in the present invention should be the common meanings understood by those skilled in the art to which the present invention belongs. In this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Terms such as "connection" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral body; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. The terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "include..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0045] The embodiment of the present invention provides a polishing disc for electrically assisted photocatalytic polishing of large-sized diamonds, so that the polishing liquid and diamonds continuously undergo oxidation reaction under photocatalysis, thereby improving the surface quality of the diamond after polishing. Exemplarily, the electrically assisted photocatalytic polishing device for large-sized diamonds can be used not only for polishing diamond wafers, but also for processing silicon carbide wafers. Based on the polishing disc for electrically assisted photocatalytic polishing of large-sized diamonds, surface polishing and wafer thinning of wafers can be achieved. The polishing disc for electrically assisted photocatalytic polishing of large-sized diamonds is described below.

[0046] Figure 1 Schematic diagram of the external structure of a polishing disc for electrically assisted photocatalytic polishing of large-sized diamonds provided by an embodiment of the present invention. Figure 1 A polishing disc for electrically assisted photocatalytic polishing of large-sized diamonds comprises: a through-hole electro-hydraulic slip ring 5, a protective shell 6, a polishing disc 7, a power supply part, and a liquid supply part.

[0047] Combination Figure 2, Figure 3 , the upper end of the through-hole electro-hydraulic slip ring is connected to the rotating spindle of the equipment, and the rotational motion is transmitted to the entire polishing disc. The upper surface of the support disc 701 is provided with multiple ring grooves, and the conductive ring 8 is placed in the ring groove. A terminal 9 is provided above each conductive ring, and the terminal 9 is connected to the power supply part. The positive pole of the external power supply is connected to the power supply part 3, and the current passes through the through-hole electro-hydraulic slip ring 5, the power supply part 301 and the terminal 9 to transmit the current to the conductive ring 801 and the conductive ring 803. The negative pole of the external power supply is connected to the power supply parts 4 and 302, and is connected to the conductive rings 802 and 804 through the terminal. The conductive rings 801 and 803 transmit the current transmitted by the external power supply to the graphite electrode 10 in the internal through hole of the polishing disc 7. At the same time, under the irradiation of the ultraviolet light source 12, the ions in the polishing liquid begin to move, and an oxidation reaction occurs with the polishing surface of the diamond to be polished under the action of the current output by the graphite electrode 10.

[0048] The ultraviolet light source 12 is fixed in the hollow part of the support plate 701 and rotates together with the polishing plate.

[0049] The intelligent cabinet is connected to the liquid supply part 1 to deliver the cooling liquid to the ultraviolet light source 12, and the cooling waste liquid flows back to the intelligent cabinet through the liquid supply part 2. The through-hole electro-hydraulic slip ring can ensure that the cooling liquid and the cooling waste liquid delivery pipelines do not interfere with each other.

[0050] The light emitted by the ultraviolet light source must meet the following conditions: at least one of the components in the polishing liquid can generate photogenerated electron-hole pairs under the irradiation of the ultraviolet light source. For example, the polishing liquid contains photocatalyst TiO2 particles. Under the irradiation of LED ultraviolet light, photogenerated electrons and holes are generated on the surface of the TiO2 particles, and water molecules in the polishing liquid react with OH － It can effectively capture photogenerated holes and generate hydroxyl radicals with strong oxidizing ability. Under the mechanical action of the abrasive, the hydroxyl radicals, as a strong oxidant, can oxidize the surface of the diamond wafer, and then the abrasive mechanically removes the oxide layer on the surface of the wafer. In the embodiment of the present invention, no oxidant needs to be added. The polishing disc is mainly irradiated with ultraviolet light to catalyze the reaction of water and oxygen in the air to generate a large number of highly active hydroxyl radicals that react with carbon atoms on the surface of the diamond to achieve polishing of the diamond surface.

[0051] In the embodiment of the present invention, the polishing plate support plate 701 is made of resin, and may also be made of glass or other insulating materials. The polishing plate contact plate 702 is made of alumina ceramic material with strong corrosion resistance. The protective shell 6 and the protective cover 11 can protect the power supply part and the ultraviolet light source, and need to be made of insulating and corrosion-resistant materials, such as resin, glass, etc.

[0052] In the embodiment of the present invention, the polishing disc can achieve a rotation speed of 100-1000 rpm without a drive, and can achieve a rotation speed of 1000-3000 rpm if the polishing disc is installed on a spindle.

[0053] Figure 3 Schematic diagram of the cross-sectional structure of a polishing disc for electrically assisted photocatalytic polishing of large-sized diamonds provided by an embodiment of the present invention. Figure 3 The internal structure of the polishing disc for electro-assisted photocatalytic polishing of large-sized diamonds and the installation method of each component can be clearly understood. The liquid conveying part 101 inputs the cooling liquid conveyed from the outside into the ultraviolet light source 12 to cool the ultraviolet light source and ensure that the ultraviolet light source works safely and effectively. The used cooling waste liquid flows back to the intelligent cabinet through the liquid conveying part 201.

[0054] Figure 4 Schematic diagram of the top view of the support plate provided by an embodiment of the present invention. Figure 4 The embodiment of the present invention adopts a concentric circular ring groove arrangement, and the number of the ring grooves is an even number. A plurality of ring grooves are arranged on the upper surface of the polishing disk support disk for placing conductive rings, and a plurality of through holes are arranged in the ring grooves for placing graphite electrodes.

[0055] Figure 5 is a schematic diagram of a top view of the contact disk provided by an embodiment of the present invention. Figure 5 The polishing plate contact plate is provided with through holes corresponding to the polishing plate support plate one by one, for placing graphite electrodes.

[0056] The embodiment of the present invention adopts a combined polishing disc, wherein the upper disc is a support disc and the lower disc is a contact disc. During the polishing process, the contact disc contacts the abrasive particles in the polishing liquid and wears out. The contact disc is made of alumina ceramic material and adopts a combined design, which can reduce costs, facilitate processing, and facilitate replacement after wear.

[0057] During the process of electro-assisted photocatalytic polishing of large-sized diamonds, the various reactions that occur are as follows:

[0058] The polishing liquid contains photocatalyst TiO2 particles. Under the irradiation of LED ultraviolet light, photogenerated electrons and holes are generated on the surface of TiO2 particles, and water molecules in the polishing liquid react with OH to form a photocatalyst. － It can effectively capture photogenerated holes and generate hydroxyl radicals with strong oxidizing ability. Under the mechanical action of the abrasive, the hydroxyl radicals act as strong oxidants to oxidize the diamond surface, and then the abrasive mechanically removes the oxide layer on the wafer surface.

[0059] As a strong oxidant in electro-assisted photocatalytic polishing, the generation mechanism of hydroxyl radicals under the irradiation of LED ultraviolet light source is as follows:

[0060] TiO2+hv→h＋ +e －

[0061] h ＋ +H2O→H ＋ +—OH

[0062] h++OH － →—OH

[0063] e － +H2O2→—OH+OH －

[0064] e-+O2→O2 －

[0065] O2 － +H2O2→—OH+OH － +O2

[0066] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A polishing disc for electrically assisted photocatalytic polishing of large-sized diamonds, characterized in that: include: A support disk, wherein the support disk is a hollow structure, wherein a plurality of through holes are arranged in the support disk and a plurality of ring grooves are arranged on the upper surface thereof, wherein the through holes are used to place graphite electrodes and the ring grooves are used to place conductive rings; A contact plate is arranged below the support plate, and a plurality of through holes are evenly arranged on the contact plate, and the positions of the through holes correspond to the support plate one by one; A conductive ring is disposed in the ring groove above the support plate and contacts the graphite electrode to form an electrical circuit; A polishing head is arranged below the contact plate, and a diamond placement groove is arranged on the upper surface of the polishing head for placing the diamond to be polished; A polishing pad is arranged on the surface to be polished of the diamond to be polished, and the area of ​​the polishing pad is greater than or equal to the area of ​​the surface to be polished; A light source, which is an ultraviolet light source, is disposed in the middle of the support plate; the light emitted by the light source irradiates the polishing surface of the diamond to be polished; A liquid supply part, used for providing cooling liquid to the light source and recovering waste liquid; During the polishing process, the liquid supply part inputs external cooling liquid into the light source through the electro-hydraulic slip ring; A through-hole electro-hydraulic slip ring is arranged above the support plate and is used to transmit liquid, current and motion to the polishing plate. The through-hole electro-hydraulic slip ring has two inlets and two outlets for liquid passage, allowing two liquids to pass through. The polishing liquid is any one or any combination of P25 nano-TiO2 photocatalyst polishing liquid, 5nm TiO2 photocatalyst polishing liquid, cerium oxide and zirconium oxide; A power supply, wherein the power supply is an external power supply, wherein the positive electrode and the negative electrode of the power supply are respectively connected to the positive electrode and the negative electrode of the upper end of the through-hole electro-hydraulic slip ring, and the positive electrode and the negative electrode of the lower end of the through-hole electro-hydraulic slip ring are respectively connected to the positive and negative electrodes of the conductive ring and the light source, and the polishing liquid generates free-moving electrons under the irradiation of the light source, and at the same time, an electric field is formed by connecting the conductive ring and the conductive graphite with the conductive polishing liquid to realize the polishing process; In the polishing process, polishing liquid is dripped into the polishing pad, and at the same time, the polishing pad and the polishing disc grind the polishing surface of the diamond to be polished; at the same time, under the irradiation of the light source, the polishing liquid and the polishing surface of the diamond to be polished undergo an oxidation reaction, thereby realizing the polishing process; The polishing liquid contains photocatalyst TiO2 particles. Under the irradiation of LED ultraviolet light, photogenerated electrons and holes are generated on the surface of TiO2 particles, and water molecules in the polishing liquid react with OH － It can effectively capture photogenerated holes and generate hydroxyl radicals with strong oxidizing ability. Under the mechanical action of the abrasive, the hydroxyl radicals act as strong oxidants to oxidize the diamond surface, and then the abrasive mechanically removes the oxide layer on the wafer surface. As a strong oxidant in electro-assisted photocatalytic polishing, the generation mechanism of hydroxyl radicals under the irradiation of LED ultraviolet light source is as follows: TiO2+hv→h + +and － h + +H2O→H + +—OH h++OH － →—OH e － +H2O2→—OH+OH － e-+O2→O2 － O2 － +H2O2→—OH+OH － +O2。 2. A polishing disc for electrically assisted photocatalytic polishing of large-sized diamonds according to claim 1, characterized in that: The supporting plate and the contact plate of the polishing plate are glued and fixed, and the through holes on the two plates correspond to each other one by one.

3. A polishing disc for electrically assisted photocatalytic polishing of large-sized diamonds according to claim 1, characterized in that: The light source is an ultraviolet light source, and the light source includes one or more of a UV ultraviolet curing lamp, a mercury lamp ultraviolet light source, a short arc xenon lamp, and a high-intensity metal halide lamp.

4. A polishing disc for electrically assisted photocatalytic polishing of large-sized diamonds according to claim 1, characterized in that: Also includes: Rotating component: connected to the polishing disc and used to control the polishing disc to rotate around its central axis.

5. The polishing disc for electrically assisted photocatalytic polishing of large-sized diamonds according to claim 1, characterized in that: The polishing disc annular groove is concentric, radial or spiral.

6. A method for polishing large-size diamonds by electro-assisted photocatalytic polishing, characterized in that: A polishing disc for electrically assisted photocatalytic polishing of large-sized diamonds as claimed in any one of claims 1 to 5, wherein the electrically assisted photocatalytic polishing of large-sized diamonds comprises: Insert the diamond to be polished into the diamond placement groove on the polishing head; Placing a polishing pad on the polishing surface of the diamond to be polished, and fixing the polishing pad; Supplying polishing liquid into the polishing pad to fully wet the polishing pad; Starting the power supply and turning on the ultraviolet light source, so that the ultraviolet light source irradiates the surface of the diamond to be polished, connects the circuit on the polishing disk, and forms a loop with the free mobile electrons in the polishing liquid; The rotating spindle is started, and the polishing process begins. Under the action of chemical mechanical polishing, the polishing surface of the diamond to be polished is polished.

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