CN118204900A - Polishing pad, chemical mechanical polishing equipment and polishing method - Google Patents

Abstract

The present disclosure relates to a polishing pad, a chemical mechanical polishing device and a polishing method. The polishing pad comprises: a first surface and a second surface arranged opposite to each other. The first surface is provided with a plurality of grooves arranged in sequence from the outside to the inside. The ratio of the spacing between any adjacent grooves to the radius of the polishing pad is 8/25 to 12/25. The polishing pad in the embodiment of the present disclosure can make the contact area between the object to be polished and the polishing pad larger, which is conducive to improving the polishing efficiency and further improving the production efficiency.

Description

Polishing pad, chemical mechanical polishing apparatus and polishing method

Technical Field

The present disclosure relates to the field of semiconductor technologies, and in particular, to a polishing pad, a chemical mechanical polishing apparatus, and a polishing method.

Background

When the chemical mechanical polishing equipment is used for polishing the wafer, if a new polishing head is used, the thickness of the positioning ring of the new polishing head cannot meet the production requirement, so that the polishing rate of the edge of the wafer to be polished is insufficient, and residues are generated. Therefore, when using a new polishing head, a certain polishing consumption is required for the positioning ring in the new polishing head, so that the new polishing head meets the production requirement.

However, the polishing time of the new polishing head is too long, which seriously affects the usable time of the chemical mechanical polishing equipment, so that the consumption in the production process cannot be satisfied.

Therefore, how to improve the polishing efficiency, thereby shortening the polishing time of the new polishing head and further improving the production efficiency is a problem to be solved.

Disclosure of Invention

Accordingly, in order to solve the above-mentioned problems in the related art, it is necessary to provide a polishing pad, a chemical mechanical polishing apparatus, and a polishing method, which can improve polishing efficiency, thereby shortening polishing time of a new polishing head and improving production efficiency.

To solve the above technical problems, according to some embodiments, an aspect of the present disclosure provides a polishing pad, including: the first surface and the second surface are oppositely arranged. The first surface is provided with a plurality of grooves which are sequentially distributed at intervals from outside to inside. The ratio of the spacing between any adjacent grooves to the radius of the polishing pad is 8/25-12/25.

In the embodiment of the disclosure, the first surface of the polishing pad is provided with a plurality of grooves which are sequentially arranged at intervals from outside to inside, and the ratio of the interval between any two adjacent grooves to the radius of the polishing pad is 8/25-12/25. The present disclosure provides polishing pads with specific patterns by reducing the number of grooves, i.e., by increasing the spacing between adjacent grooves in the polishing pad, relative to conventional polishing pads. Therefore, the polishing pad in the embodiment of the disclosure can make the contact area between the object to be polished and the polishing pad larger, thereby being beneficial to improving the polishing efficiency and further improving the production efficiency.

According to some embodiments, the pad has a shore hardness of not less than 65.

In the embodiment of the disclosure, the polishing efficiency can be further improved by adopting the polishing pad with high hardness, so that the production efficiency is further improved.

According to some embodiments, the widths of the plurality of grooves are all equal.

According to some embodiments, the pitch of any adjacent grooves is equal.

According to some embodiments, the spacing between the outermost grooves and the outer edge of the polishing pad is less than the spacing between adjacent grooves. The spacing between the innermost grooves and the center of the polishing pad is less than the spacing between adjacent grooves.

According to some embodiments, another aspect of the present disclosure provides a chemical mechanical polishing apparatus comprising a polishing pad as described in some embodiments above and a polishing head. The grinding head is arranged above the grinding pad and comprises a grinding head main body and a positioning ring arranged on the lower surface of the grinding head main body. The positioning ring is contacted with the first surface of the polishing pad.

In the embodiment of the disclosure, the chemical mechanical polishing device comprises a polishing pad and a polishing head, wherein a plurality of grooves are sequentially arranged on the first surface of the polishing pad at intervals from outside to inside, and the ratio of the distance between any two adjacent grooves to the radius of the polishing pad is 8/25-12/25. The present disclosure provides polishing pads with specific patterns by reducing the number of grooves, i.e., by increasing the spacing between adjacent grooves in the polishing pad, relative to conventional polishing pads. Therefore, the polishing pad in the embodiment of the disclosure can make the contact area between the positioning ring of the new polishing head and the polishing pad larger, thereby being beneficial to improving the polishing efficiency and further improving the production efficiency.

According to some embodiments, the chemical mechanical polishing apparatus further comprises: a grinding disc and a grinding fluid supply device. One side surface of the grinding disc is covered with a grinding pad and is contacted with the second surface of the grinding pad. The polishing liquid supply device extends from one side of the polishing disc to the upper part of the polishing pad and is used for supplying polishing liquid to the polishing pad.

According to some embodiments, a further aspect of the present disclosure provides a grinding method comprising: providing a chemical mechanical polishing apparatus as described in some embodiments above; placing a wafer to be polished in a positioning ring of a polishing head; the surface to be ground of the wafer to be ground is contacted with the first surface of the grinding pad; providing a polishing liquid to the first surface of the polishing pad by a polishing liquid supply device; the surface to be polished is polished by using a polishing head.

In the embodiment of the disclosure, the first surface of the polishing pad is provided with a plurality of grooves which are sequentially arranged at intervals from outside to inside, and the ratio of the interval between any two adjacent grooves to the radius of the polishing pad is 8/25-12/25. The present disclosure provides polishing pads with specific patterns by reducing the number of grooves, i.e., by increasing the spacing between adjacent grooves in the polishing pad, relative to conventional polishing pads. Therefore, the polishing pad in the embodiment of the disclosure can make the contact area between the positioning ring of the new polishing head and the polishing pad larger, thereby being beneficial to improving the polishing efficiency and further improving the production efficiency.

According to some embodiments, before placing the wafer to be polished into the retaining ring of the polishing head, the method further comprises: providing a polishing liquid to the first surface of the polishing pad by a polishing liquid supply device; the positioning ring is adjusted by using the polishing liquid and the polishing pad.

According to some embodiments, the polishing liquid comprises silica. The mass percentage of the silicon dioxide in the grinding liquid is not less than 20 percent.

In the embodiment of the disclosure, the consumption speed of the positioning ring in the new grinding head can be rapidly increased by using the silicon dioxide grinding fluid with higher solid content and matching with high grinding pressure and rotating speed, so that the grinding head can rapidly reach the production requirement.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings required for the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present disclosure, and other drawings may be obtained according to these drawings without inventive effort for a person of ordinary skill in the art.

FIG. 1 (a) is a schematic top view of a polishing pad according to one embodiment of the present disclosure;

FIG. 1 (b) is a schematic cross-sectional view of a polishing pad according to one embodiment of the present disclosure;

FIG. 2 is a schematic cross-sectional view of a chemical mechanical polishing apparatus according to an embodiment of the disclosure;

Fig. 3 is a flow chart of a polishing method according to an embodiment of the present disclosure.

Reference numerals illustrate:

1-a polishing pad; 11-grooves; 12-a first surface; 13-a second surface; 2-grinding head; 21-a polishing head body; 22-positioning rings; 3-grinding disc; 4-a grinding fluid supply device; 41-grinding fluid; 5-a wafer to be ground; 6-soft cushion.

Detailed Description

In order that the disclosure may be understood, a more complete description of the disclosure will be rendered by reference to the appended drawings. Embodiments of the present disclosure are illustrated in the accompanying drawings. This disclosure may, however, be embodied in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. The terminology used in the description of the disclosure herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure.

It will be understood that when an element or layer is referred to as being "on," "adjacent," "connected to," or "coupled to" another element or layer, it can be directly on, adjacent, connected, or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being "directly on," "directly adjacent to," "directly connected to," or "directly coupled to" another element or layer, there are no intervening elements or layers present. It will be understood that, although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the present disclosure.

Spatially relative terms, such as "under", "below", "beneath", "under", "above", "over" and the like, may be used herein to describe one element or feature's relationship to another element or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use and operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements or features described as "under" or "beneath" other elements would then be oriented "on" the other elements or features. Thus, the exemplary terms "below" and "under" may include both an upper and a lower orientation. Furthermore, the device may also include an additional orientation (e.g., rotated 90 degrees or other orientations) and the spatial descriptors used herein interpreted accordingly.

As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. Also, as used herein, the term "and/or" includes any and all combinations of the associated listed items.

As used herein, a "deposition" process includes, but is not limited to, physical vapor deposition (Physical Vapor Deposition, PVD for short), chemical vapor deposition (Chemical Vapor Deposition, CVD for short), or atomic layer deposition (Atomic Layer Deposition, ALD for short).

In integrated circuit fabrication, chemical mechanical polishing processes are an important process for planarizing the wafer surface as the device size is shrinking. When the chemical mechanical polishing equipment is used for polishing the wafer, if a new polishing head is used, the thickness of the positioning ring of the new polishing head cannot meet the production requirement, so that the polishing rate of the edge of the wafer to be polished is insufficient, and residues are generated. Therefore, when using a new polishing head, a certain polishing consumption is required for the positioning ring in the new polishing head, so that the new polishing head meets the production requirement. However, the polishing time of the new polishing head is too long, which seriously affects the usable time of the chemical mechanical polishing equipment, so that the consumption in the production process cannot be satisfied.

Chemical mechanical polishing is accomplished by tightly attaching a semiconductor wafer in a polishing head to a rotating polishing surface or otherwise moving the wafer relative to the polishing surface under controlled temperature, pressure, and chemical composition conditions. The polishing surface may be a planar polishing pad formed of a relatively soft porous material (e.g., foamed polyurethane) and wetted with an aqueous slurry seat slurry that is chemically active and abrasive. The aqueous slurry may be acidic or basic and typically includes abrasive particles, reactive chemicals such as transition metal chelating salts or oxidizing agents, and adjuvants such as solvents, buffers, and passivating agents. In the slurry, salts or other reagents provide a chemical etching action. And the abrasive particles, together with the polishing pad, provide a mechanical polishing action. During the polishing process, slurry is continuously supplied to the polishing pad through one or more nozzles.

Based on the above, the disclosure provides a polishing pad, a chemical mechanical polishing apparatus and a polishing method, which can improve polishing efficiency, thereby shortening polishing time of a new polishing head and improving production efficiency.

Referring to fig. 1 (a) and 1 (b), some embodiments of the present disclosure provide a polishing pad 1, comprising: a first surface 12 and a second surface 13 disposed opposite to each other. The first surface 12 is provided with a plurality of grooves 11 which are sequentially arranged at intervals from outside to inside. The ratio of the spacing between any adjacent grooves 11 (e.g., D1 and D2) to the radius r of the polishing pad 1 is 8/25 to 12/25.

In the embodiment of the disclosure, the first surface 12 of the polishing pad 1 is provided with a plurality of grooves 11 sequentially arranged at intervals from outside to inside, and the ratio of the space between any adjacent grooves 11 (e.g., D1 and D2) to the radius r of the polishing pad 1 is 8/25-12/25. The present disclosure results in a polishing pad 1 having a particular pattern by reducing the number of grooves 11, i.e., by increasing the spacing (e.g., D1 and D2) between adjacent grooves 11 in the polishing pad 1, relative to conventional polishing pads. Thus, the polishing pad 1 in the embodiment of the disclosure can make the contact area between the object to be polished and the polishing pad 1 larger, thereby being beneficial to improving the polishing efficiency and further improving the production efficiency.

In some embodiments, the polishing pad 1 is formed by bonding a base pad and a polishing layer in a stacked arrangement to form a single unit, and the physical and chemical properties of the whole unit are uniform.

In some examples, the polishing pad 1 has a diameter dimension that is greater than the diameter dimension of a subsequent wafer to be polished.

Specifically, the size difference range between the diameter size of the polishing pad 1 and the diameter size of the wafer to be polished subsequently includes: 5 mm-20 mm. For example: the difference in the diameter size of the polishing pad 1 from the diameter size of the wafer to be polished is 5mm, 10mm, 15mm, 20mm, or the like.

In some examples, the ratio of the spacing between any adjacent grooves 11 (e.g., D1 and D2) to the radius r of the polishing pad 1 may be: 8/25, 9/25, 2/5, 11/25 or 12/25, etc.

In some embodiments, the shore hardness of the polishing pad 1 is not less than 65.

In some examples, the pad 1 may have a shore hardness of 65, 70, 75, 80, 85, or the like.

In the embodiment of the disclosure, the polishing pad 1 with high hardness is adopted, so that the polishing efficiency can be further improved, and the production efficiency can be further improved.

In some embodiments, the widths of the plurality of grooves 11 are all equal.

In some embodiments, the spacing (e.g., D1 and D2) of any adjacent grooves 11 is equal.

In some embodiments, the spacing D1 between the outermost grooves 11 and the outer edge of the polishing pad 1 is less than the spacing between adjacent grooves 11 (e.g., D1 and D2). The spacing D2 between the innermost groove 11 and the center O of the polishing pad 1 is smaller than the spacing between adjacent grooves 11 (e.g., D1 and D2).

Referring to fig. 2, some embodiments of the disclosure further provide a chemical mechanical polishing apparatus including the polishing pad 1 and the polishing head 2 described in some embodiments above. The polishing head 2 is disposed above the polishing pad 1 and includes a polishing head body 21 and a positioning ring 22 disposed on a lower surface of the polishing head body 21. The retaining ring 22 is in contact with the first surface 12 of the polishing pad 1.

In the embodiment of the disclosure, the chemical mechanical polishing apparatus includes a polishing pad 1 and a polishing head 2, where a first surface 12 of the polishing pad 1 is provided with a plurality of grooves 11 sequentially arranged from outside to inside at intervals, and a ratio of a space (e.g., D1 and D2) between any adjacent grooves 11 to a radius r of the polishing pad 1 is 8/25-12/25. The present disclosure results in a polishing pad 1 having a particular pattern by reducing the number of grooves 11, i.e., by increasing the spacing (e.g., D1 and D2) between adjacent grooves 11 in the polishing pad 1, relative to conventional polishing pads. In this way, the polishing pad 1 in the embodiment of the disclosure can make the contact area between the positioning ring 22 of the new polishing head 2 and the polishing pad 1 larger, so as to be beneficial to improving the polishing efficiency and further improving the production efficiency.

In some embodiments, referring to fig. 2, the polishing head 2 includes a polishing head body 21, a retaining ring 22, and at least two air chambers (not shown). At least two air chambers are provided at the outer surface of the grinding bit body 21.

Illustratively, the grinding bit 2 has two air chambers, which are arranged corresponding to the two sub-channels of the grinding bit body 21. Each air chamber is connected to a respective one of the sub-channels in the polishing head body 21 and configured to generate an air flow.

In some embodiments, referring to FIG. 2, the polishing head body 21 has a rotational axis. The air chambers are spaced apart at substantially equal angular intervals about the axis of rotation of the polishing head body 21. The two air chambers may be spaced apart at 180 degree intervals about the rotational axis of the polishing head body 21. The grinding bit body 21 includes an axial portion and a base portion connected to the axial portion. The base portion has an upper surface, sides and a lower surface. The cavity of the polishing head body 21 is provided at the lower surface of the base portion. The main channel is provided at an axial portion of the polishing head body, and the sub-channels are provided at a base portion of the polishing head body 21.

Illustratively, each sub-channel has an opening disposed at a side of the base portion of the grinding bit body 21. Each air chamber is connected to an opening of each sub-channel.

In some embodiments, referring to fig. 2, the polishing head 2 is used to polish the wafer 5 to be polished with a polishing liquid. The cushion 6 is disposed between the polishing head 2 and the wafer 5 to be polished, and the wafer 5 to be polished can be tightly attached to the cushion 6 by using partial vacuum or an adhesive. The grinding bit 2 is arranged to be continuously rotated in a first direction and optionally to be reciprocated laterally in a second direction by a drive motor. Accordingly, the combined rotational and lateral movement of the wafer 5 to be polished aims to reduce the difference in material removal rate on the surface of the wafer 5 to be polished.

According to some embodiments, the chemical mechanical polishing apparatus further comprises: a polishing plate 3 and a polishing liquid supply device 4. One side surface of the polishing disk 3 is covered with the polishing pad 1 and is in contact with the second surface 13 of the polishing pad 1. The polishing liquid supply device 4 extends from one side of the polishing disk 3 to above the polishing pad 1, and is configured to supply the polishing liquid to the polishing pad 1.

Specifically, in some embodiments, referring to FIG. 2, the polishing pad 1 is mounted on a polishing platen 3. The polishing disc 3 has a relatively large surface area compared to the wafer 5 to be polished to accommodate the translational movement of the wafer 5 to be polished on the polishing head 2 over the surface of the polishing pad 1. A polishing liquid supply device 4 is installed above the polishing platen 3 to deliver a polishing liquid, which is dropped from a nozzle of the polishing liquid supply device 4 onto the surface of the polishing pad 1. The slurry may be gravity fed from a reservoir or container or otherwise pumped to the slurry supply 4. In addition, the polishing liquid may be supplied from below the polishing pad 3 so that the polishing liquid flows upward through the bottom surface of the polishing pad 1.

In some embodiments, the chemical mechanical polishing apparatus may include a motor. The motor can drive the grinding disc 3 to rotate. The polishing disc 3 drives the polishing pad 1 to rotate through the carrying machine, and cooperates with the polishing liquid to perform the chemical mechanical polishing process on the positioning ring 22 of the new polishing head 2.

In some examples, the chemical mechanical polishing apparatus further comprises: grinding disc cleaning system, water spraying mechanism and water absorbing mechanism. The grinding disc cleaning system is arranged on the grinding table and above the grinding disc 3 and is used for brushing the grinding disc 3. The water spraying mechanism is arranged on the grinding table and is positioned above the grinding disc 3 and is used for spraying water to the grinding disc 3 in the cleaning process. The water absorbing mechanism is arranged on the grinding table and is positioned above the grinding disc 3 and used for absorbing the waste water and the grinding liquid on the grinding disc 3 after the cleaning is finished.

In some examples, the solids content of the slurry is higher. In this way, the polishing liquid 41 with higher solid content is adopted, so that better polishing effect can be generated between the positioning ring 22 of the new polishing head and the polishing pad 1.

In some examples, the slurry supply device 4 includes a magnetic stirring device disposed on the polishing table, a stand, and an atomizer disposed on the stand. Wherein, connect through the grinding fluid conveyer pipe between magnetic stirring device and the atomizer, the atomizer is connected with compressed air pipeline. The magnetic stirring device is used for uniformly stirring the polishing liquid 41. The polishing liquid conveying pipe is installed on the magnetic stirring device for conveying the polishing liquid 41. The compressed air pipeline is arranged on the bracket and used for conveying compressed air. The atomizer is used to spray the polishing liquid 41. The atomizing nozzle is provided with a stainless steel cup cover which is used for controlling the spraying range.

In some examples, the abrasive disk cleaning system includes a lift cylinder disposed on the abrasive table, a rotating motor coupled to the lift cylinder, and a brush coupled to the rotating motor. The lifting electric cylinder is used for controlling the brushing brush to lift. The rotating motor is used for driving the brushing brush to rotate.

In some examples, the grinding table is coupled to a power section for driving the grinding table in rotation about its axis. Specifically, the power section includes a motor or the like.

Referring to fig. 3, another aspect of the disclosure provides a polishing method, including steps S100 to S400.

S100, providing a chemical mechanical polishing apparatus as described in some embodiments above.

S200, placing a wafer to be polished in a positioning ring of a polishing head; the surface to be polished of the wafer to be polished is contacted with the first surface of the polishing pad.

And S300, supplying the polishing liquid to the first surface of the polishing pad through a polishing liquid supply device.

S400, polishing the surface to be polished by using the polishing head.

In the embodiment of the disclosure, the first surface of the polishing pad is provided with a plurality of grooves which are sequentially arranged at intervals from outside to inside, and the ratio of the interval between any two adjacent grooves to the radius of the polishing pad is 8/25-12/25. The present disclosure provides polishing pads with specific patterns by reducing the number of grooves, i.e., by increasing the spacing between adjacent grooves in the polishing pad, relative to conventional polishing pads. Therefore, the polishing pad in the embodiment of the disclosure can make the contact area between the positioning ring of the new polishing head and the polishing pad larger, thereby being beneficial to improving the polishing efficiency and further improving the production efficiency.

In some embodiments, before placing the wafer 5 to be polished in the positioning ring 22 of the polishing head 2, the method further comprises: supplying the polishing liquid 41 to the first surface 12 of the polishing pad 1 by the polishing liquid supply device 4; the retainer ring 22 is adjusted by using the polishing liquid 41 and the polishing pad 1.

Further, illustratively, a cushion 6 is disposed between the polishing head 2 and the wafer 5 to be polished, and within the retaining ring 22.

In some embodiments, the polishing liquid 41 comprises silica. The mass percentage of silica in the polishing liquid 41 is not less than 20%. Illustratively, the polishing liquid 41 is dropped onto the surface of the polishing pad 1 from the nozzles of the polishing liquid supply apparatus 4.

In the embodiment of the disclosure, by using the silica polishing liquid 41 with higher solid content and matching with high polishing pressure and rotation speed, the consumption speed of the positioning ring 22 in the new polishing head 2 can be increased rapidly, so that the polishing head 2 can meet the production requirement rapidly.

In this specification, each embodiment is described in a progressive manner, and each embodiment is mainly described by differences from other embodiments, and identical and similar parts between the embodiments are all enough to be referred to each other.

The technical features of the above-described embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above-described embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.

The above examples merely represent a few embodiments of the present disclosure, which are described in more detail and are not to be construed as limiting the scope of the claims. It should be noted that variations and modifications can be made by those skilled in the art without departing from the spirit of the disclosure, which are within the scope of the disclosure. Accordingly, the scope of protection of the present disclosure should be determined by the following claims.

Claims (10)

1. A polishing pad, comprising: a first surface and a second surface arranged opposite to each other; the first surface is provided with a plurality of grooves arranged in sequence from the outside to the inside; the ratio of the spacing between any adjacent grooves to the radius of the polishing pad is 8/25 to 12/25. 2 . The polishing pad as claimed in claim 1 , wherein the Shore hardness of the polishing pad is not less than 65. 3 . The polishing pad as claimed in claim 1 , wherein the widths of the plurality of grooves are equal. 4 . The polishing pad as claimed in claim 1 , wherein the spacing between any adjacent grooves is equal. 5. The polishing pad as described in claim 4 is characterized in that the distance between the outermost groove and the outer edge of the polishing pad is smaller than the distance between adjacent grooves; the distance between the innermost groove and the center of the polishing pad is smaller than the distance between adjacent grooves. 6. A chemical mechanical polishing device, comprising: The polishing pad according to any one of claims 1 to 5; and A grinding head; the grinding head is arranged above the grinding pad, and comprises a grinding head body, and a positioning ring arranged on the lower surface of the grinding head body; the positioning ring is in contact with the first surface of the grinding pad. 7. The chemical mechanical polishing apparatus according to claim 6, characterized in that the chemical mechanical polishing apparatus further comprises: A grinding disc, one side surface of which is covered with the grinding pad and is in contact with the second surface of the grinding pad; A grinding liquid supply device extends from one side of the grinding disc to above the grinding pad, and is used for providing grinding liquid to the grinding pad. 8. A grinding method, characterized in that it comprises: Providing a chemical mechanical polishing apparatus as claimed in claim 7; Placing a wafer to be ground in the positioning ring of the grinding head; the surface to be ground of the wafer to be ground is in contact with the first surface of the grinding pad; Providing polishing liquid to the first surface of the polishing pad by the polishing liquid supply device; The grinding head is used to grind the surface to be ground. 9. The grinding method according to claim 8, characterized in that before placing the wafer to be ground in the positioning ring of the grinding head, it also includes: Providing polishing liquid to the first surface of the polishing pad by the polishing liquid supply device; The positioning ring is adjusted using the polishing liquid and the polishing pad. 10. The grinding method according to claim 8 or 9, characterized in that the grinding liquid comprises silicon dioxide; the mass percentage of the silicon dioxide in the grinding liquid is not less than 20%.