CN117506712A - Chemical mechanical polishing device and polishing method - Google Patents

Abstract

The invention discloses a chemical mechanical polishing device and a polishing method, wherein the chemical mechanical polishing device comprises: polishing disk; the bearing head is used for loading a wafer to be polished; the liquid supply assembly is in one-to-one correspondence with the bearing heads and comprises liquid supply arms, and the liquid supply arms are provided with a plurality of liquid supply pipes for supplying polishing liquid to the polishing pads above the polishing disk; and the online trimming assembly is integrated with the liquid supply assembly and positioned at the side of the liquid supply arm so as to trim the surface of the polishing pad online.

Description

Chemical mechanical polishing device and polishing method

Technical Field

The invention belongs to the technical field of chemical mechanical polishing, and particularly relates to a chemical mechanical polishing device and a polishing method.

Background

The integrated circuit industry is the core of the information technology industry and plays a key role in the process of converting and upgrading the boosting manufacturing industry into digital and intelligent conversion. The chip is a carrier of an integrated circuit, and the chip manufacturing involves the process flows of integrated circuit design, wafer manufacturing, wafer processing, electrical measurement, dicing packaging, testing, and the like. Among them, chemical mechanical polishing (Chemical Mechanical Polishing, CMP) is an ultra-precise surface processing technique for global planarization, which belongs to one of five major core processes in wafer fabrication processes.

The third-generation semiconductor material can meet the new requirements of the modern electronic technology on severe conditions such as high temperature, high power, high voltage, high frequency, radiation resistance and the like due to the advantages of wider forbidden band width, high thermal conductivity, high breakdown field strength, high saturated electron drift rate, gao Jian energy combination and the like, so that the third-generation semiconductor material has wide application in the industries such as radio frequency communication, radars, satellites, power management, automobile electronics, industrial power electronics and the like.

However, third generation semiconductor materials such as gallium nitride (GaN), silicon carbide (SiC), zinc oxide (ZnO), diamond, etc., have extremely high hardness, and are difficult to polish, resulting in low polishing efficiency of the CMP process. Taking silicon carbide as an example, the mohs hardness is of the order of 9.5, which is next to the hardest diamond in the world. Therefore, the CMP process for the third generation semiconductor material is not efficient, and the single wafer polishing time is long.

And particles generated by the chemical mechanical polishing may clog the porous microstructure of the polishing pad, so that the surface of the polishing pad is glazed, thereby resulting in a continuous decrease in the removal rate of the material to be polished, which is disadvantageous for the execution of the polishing process, and even reduces the yield and reliability of semiconductor elements.

Disclosure of Invention

The embodiment of the invention provides a chemical mechanical polishing device and a polishing method, which aim to at least solve one of the technical problems in the prior art.

A first aspect of an embodiment of the present invention provides a chemical mechanical polishing apparatus, including:

polishing disk;

the bearing head is used for loading a wafer to be polished;

the liquid supply assembly is in one-to-one correspondence with the bearing heads and comprises liquid supply arms, and the liquid supply arms are provided with a plurality of liquid supply pipes for supplying polishing liquid to the polishing pads above the polishing disk;

and the online trimming assembly is integrated with the liquid supply assembly and positioned at the side of the liquid supply arm so as to trim the surface of the polishing pad online.

In some embodiments, the number of the carrying heads is a plurality, and the liquid supply arm is arranged between the adjacent carrying heads.

In some embodiments, the liquid supply arm is an arc-shaped structure, and the liquid supply arm extends towards the center of the polishing disk; the liquid supply pipes are arranged at intervals along the length direction of the liquid supply arm.

In some embodiments, the in-line conditioning assembly includes a stationary arm disposed adjacent to the liquid supply arm, the conditioning disk being disposed below the stationary arm.

In some embodiments, the conditioning disk is disposed at the front end of the fixed arm, and has a shape and size that matches the shape and size of the liquid supply arm.

In some embodiments, the liquid supply assembly includes a liquid supply pivot shaft disposed outside of the polishing platen; the liquid supply arm is arranged above the liquid supply pivot shaft, and the liquid supply arm and the online trimming assembly can swing around the liquid supply pivot shaft.

In some embodiments, the number of the bearing heads is three, and the bearing heads are uniformly distributed below the fixing frame; the fixing frame can drive the bearing head to rotate reciprocally around the center of the bearing head, and the liquid supply arm follows the bearing head to swing around the liquid supply pivot shaft.

In some embodiments, the fixed arm is removably attached to a side of the fluid supply arm.

In some embodiments, the liquid supply arm is provided with a clamping piece, and the fixed arm is arranged on the clamping piece; the fixed arm is movable along the length direction of the liquid supply arm to adjust the position of the conditioning disk.

A second aspect of the embodiments of the present invention provides a polishing method using the chemical mechanical polishing apparatus described above, comprising:

s1, loading a wafer by a bearing head and pressing a polishing pad above a polishing disk to implement chemical mechanical polishing;

s2, supplying polishing liquid to the polishing area by the liquid supply assembly, and online dressing the surface of the polishing pad by the online dressing assembly integrated with the liquid supply assembly.

In some embodiments, the carrier head can reciprocally rotate with respect to the center of the polishing platen, and the online conditioning assembly follows the carrier head to change the conditioning position.

A third aspect of an embodiment of the present invention provides a chemical mechanical polishing apparatus, comprising:

polishing disk;

the bearing head is used for loading a wafer to be polished;

the liquid supply assembly is in one-to-one correspondence with the bearing heads and comprises liquid supply arms, and the liquid supply arms are provided with a plurality of liquid supply pipes for supplying polishing liquid to the polishing pads above the polishing disk;

the online trimming assembly is integrated on the liquid supply assembly and positioned at the side of the liquid supply arm so as to trim the surface of the polishing pad online;

and the off-line dressing assembly is arranged at the side of the polishing disc so as to finish the surface of the polishing pad off-line.

In some embodiments, the liquid supply assembly includes a liquid supply pivot shaft disposed outside of the polishing platen; and a liquid supply arm is arranged above the liquid supply pivot shaft, and the liquid supply arm and the online trimming assembly swing around the liquid supply pivot shaft.

In some embodiments, the number of the bearing heads is three, and the bearing heads are uniformly distributed below the fixing frame; the fixing frame can drive the bearing head to rotate reciprocally around the center of the bearing head, and the liquid supply arm follows the bearing head to swing around the liquid supply pivot shaft.

In some embodiments, the offline conditioning assembly includes a conditioning pivot shaft with a conditioning arm disposed thereon, an end of the conditioning arm configured with a conditioner to condition the polishing pad surface offline.

In some embodiments, the dressing pivot axis is disposed outside the polishing platen and between adjacent liquid supply pivot axes, and the dresser is capable of pressing against the polishing pad to perform a dressing operation.

In some embodiments, the liquid supply arm is an arc-shaped structure, extends towards the center of the polishing disk and is positioned between adjacent bearing heads; the liquid supply pipes are arranged at intervals along the length direction of the liquid supply arm.

In some embodiments, the in-line conditioning assembly includes a stationary arm disposed adjacent to the liquid supply arm, an end of the stationary arm configured with a conditioning disk; the trimming disc is arranged at the front end of the fixed arm, and the outer shape and the size of the trimming disc are matched with those of the liquid supply arm.

A fourth aspect of the embodiments of the present invention provides a polishing method using the chemical mechanical polishing apparatus described above, comprising:

s10, a carrying head loads a wafer and presses against a polishing pad above a polishing disk, and a liquid supply assembly supplies polishing liquid to the polishing pad so as to implement chemical mechanical polishing;

s20, in the polishing process, an online trimming assembly is used for trimming the polishing pad;

and S30, after polishing is finished, the bearing head is far away from the polishing disc, and the offline dressing assembly is used for dressing the polishing pad.

In some embodiments, the carrier head can reciprocally rotate with respect to the center of the polishing platen, and the online conditioning assembly follows the carrier head to change the conditioning position.

The beneficial effects of the invention include:

a. the online trimming assembly is integrated on the liquid supply assembly, so that the structure is simplified, the space occupation of the chemical mechanical polishing device is reduced, and the convenience of operation is improved;

b. the chemical mechanical polishing device is provided with an online trimming component so as to trim the surface of the polishing pad in the polishing process, further maintain the characteristics of the polishing pad and ensure the polishing removal rate of the wafer;

c. in the polishing process, the carrier head can rotate back and forth by taking the center of the polishing disc as a reference, and the online trimming assembly moves along with the carrier head so as to change the trimming operation position, so that the trimming disc can cover the active area of the wafer and maintain the polishing characteristic of the polishing pad.

Drawings

The advantages of the present invention will become more apparent and more readily appreciated from the detailed description given in conjunction with the following drawings, which are meant to be illustrative only and not limiting of the scope of the invention, wherein:

FIG. 1 is a schematic view of a chemical mechanical polishing apparatus according to an embodiment of the present invention;

FIG. 2 is a schematic illustration of the liquid supply assembly of the embodiment of FIG. 1;

FIG. 3 is a bottom view of the liquid supply assembly of FIG. 2;

FIG. 4 is an enlarged view of a portion of the rectangular box of FIG. 3;

FIG. 5 is a schematic view of the chemical mechanical polishing apparatus of FIG. 1 showing a holder;

FIG. 6 is a flow chart of a polishing method according to an embodiment of the present invention;

FIG. 7 is a schematic view of a chemical mechanical polishing apparatus according to another embodiment of the present invention;

fig. 8 is a flowchart of a polishing method according to another embodiment of the present invention.

Detailed Description

The following describes the technical scheme of the present invention in detail with reference to specific embodiments and drawings thereof. The examples described herein are specific embodiments of the present invention for illustrating the concept of the present invention; the description is intended to be illustrative and exemplary in nature and should not be construed as limiting the scope of the invention in its aspects. In addition to the embodiments described herein, those skilled in the art can adopt other obvious solutions based on the disclosure of the claims of the present application and the specification thereof, including those adopting any obvious substitutions and modifications to the embodiments described herein.

The drawings in the present specification are schematic views, which assist in explaining the concept of the present invention, and schematically show the shapes of the respective parts and their interrelationships. It should be understood that for the purpose of clearly showing the structure of various parts of embodiments of the present invention, the drawings are not drawn to the same scale and like reference numerals are used to designate like parts in the drawings.

In the present invention, "chemical mechanical polishing (Chemical Mechanical Polishing, CMP)" is also referred to as "chemical mechanical planarization (Chemical Mechanical Planarization, CMP)", and Wafer (W) is also referred to as Substrate (Substrate), the meaning and actual function are equivalent. The term "comprising" and its like are to be construed as open-ended, i.e., including, but not limited to. The term "based on" should be understood as "based at least in part on". The term "one embodiment" or "the embodiment" should be understood as "at least one embodiment". The terms "first," "second," and the like, may refer to different or the same object and are used solely to distinguish one from another without implying a particular spatial order, temporal order, order of importance, etc. of the referenced objects. In some embodiments, the values, processes, selected items, determined items, devices, means, parts, components, etc. are referred to as "best," "lowest," "highest," "smallest," "largest," etc. It should be understood that such description is intended to indicate that a selection may be made among many available options of functionality, and that such selection need not be better, lower, higher, smaller, larger, or otherwise preferred in further or all respects than other selections.

Fig. 1 is a schematic view of a chemical mechanical polishing apparatus 100 according to an embodiment of the present invention, where the chemical mechanical polishing apparatus 100 includes:

a polishing disk 10, a polishing pad is arranged above the polishing disk 10, and a driving device is arranged below the polishing disk 10 to drive the polishing disk 10 to rotate around the central axis thereof;

a carrier head 20 for loading a wafer to be polished; the carrying head 20 is provided with a rotary driving device to drive the carrying head 20 and the wafer loaded by the carrying head to rotate so as to finish chemical mechanical polishing in a matching way;

the liquid supply assemblies 30 are in one-to-one correspondence with the bearing heads 20; that is, the number of the liquid supply assemblies 30 is the same as the number of the carrier heads 20 to supply the polishing liquid to the wafers loaded by the respective carrier heads 20, respectively;

further, the liquid supply assembly 30 includes a liquid supply arm 31 shown in fig. 2, and the liquid supply arm 31 is provided with a plurality of liquid supply pipes 32 to supply the polishing liquid toward the polishing pad above the polishing platen 10.

In the embodiment shown in fig. 1, the cmp apparatus 100 further includes an in-line conditioning assembly 40 integrated with the liquid supply assembly 30, and the in-line conditioning assembly 40 is located at a side of the liquid supply arm 31 to in-line condition the surface of the polishing pad, thereby preventing particulate matter from blocking the porous microstructure of the surface of the polishing pad and stabilizing the polishing characteristics of the polishing pad.

In the present invention, the number of the carrier heads 20 is plural to polish plural wafers simultaneously above the polishing disk 10, so as to improve the working efficiency of the chemical mechanical polishing apparatus 100, to solve the problem of excessively long polishing time of the third generation semiconductor material, and to control the cost of wafer manufacturing. In fig. 1, the carrier head 20 is three in number and is disposed substantially uniformly over the polishing pad above the polishing platen 10.

The liquid supply arm 31 shown in fig. 2 is disposed between the adjacent carrier heads 20 to supply the polishing liquid toward the active area of the corresponding carrier head 20.

Further, the liquid supply arm 31 has an arc structure, and extends toward the center of the polishing disk 10 to adapt to the problem of insufficient space as much as possible, so that the liquid supply pipe 30 of the liquid supply arm 31 can cover the radial direction of the polishing pad, and further supply the polishing liquid on the surface of the rotating polishing pad.

The number of liquid supply pipes 32 is plural, and they are arranged at intervals along the longitudinal direction of the liquid supply arm 31 to supply the polishing liquid to the corresponding area in accordance with the polishing process.

In some embodiments, in-line conditioning assembly 40 includes a stationary arm 41, as shown in fig. 2, stationary arm 41 is disposed adjacent to liquid supply arm 31, and conditioning disk 42 is disposed below stationary arm 41.

Fig. 3 is a bottom view of the in-line conditioning assembly 40 corresponding to fig. 2, wherein a conditioning disk 42 is disposed at the front end of the fixing arm 41, and the outer shape and size of the conditioning disk 42 match the outer shape and size of the liquid supply arm 31. Specifically, the dressing disc 42 has a strip structure, and a plurality of diamonds are inlaid above the dressing disc to realize dressing of the polishing pad, prevent glazing of the surface of the polishing pad, and further maintain polishing characteristics of the polishing pad.

Fig. 4 is an enlarged view of a portion of the rectangular frame of fig. 3, and the conditioning disk 42 has a waist-shaped structure, and a plurality of diamonds are uniformly distributed on the upper portion thereof to ensure the material removing performance of the conditioning disk 42.

As one aspect of the present embodiment, at least part of the conditioning disk 42 is located on the front side of the liquid supply arm 31 so that the conditioning disk 42 can be located closer to the center of the polishing pad, and the conditioning disk 42 can substantially cover the surface of the polishing pad to complete the conditioning of the polishing area, maintaining the polishing characteristics of the polishing pad. That is, the in-line dressing assembly 40 is capable of dressing the active area of the carrier head 20 to maintain a good polishing removal rate, which is advantageous for improving the operation efficiency of the chemical mechanical polishing apparatus 100.

The liquid supply assembly 30 further includes a liquid supply pivot shaft 33 shown in fig. 2, which is disposed outside the polishing platen 10; a liquid supply arm 31 is provided above the liquid supply pivot shaft 33, and the liquid supply arm 31 and the online dressing assembly 40 can swing around the liquid supply pivot shaft 33 to simultaneously realize polishing liquid supply and dressing of the polishing pad.

It should be noted that the liquid supply pivot shaft 33 is movable in the vertical direction to avoid interference of the dressing disk 42 swinging toward the center with the polishing disk 10 and the polishing pad thereon, and the liquid supply pivot shaft 33 is pressed toward the lower side so that the dressing disk 42 acts on the polishing pad with a certain dressing force.

In the invention, the online trimming assembly 40 is integrated on the liquid supply assembly 30, and a trimming swing driving device is not required to be additionally arranged, so that the structure is simplified, the space occupation is reduced, and the convenience of polishing operation is improved.

In the present invention, the number of the carrying heads 20 is three, and the carrying heads are uniformly distributed below the fixing frame 21, as shown in fig. 5; the fixing frame 21 can drive the carrier head 20 to reciprocally rotate around the central axis of the fixing frame 21, and the liquid supply arm 31 follows the carrier head 20 to swing around the liquid supply pivot shaft 33, so as to avoid collision between movable components.

In the present invention, the fixing arm 41 is detachably connected to the side of the liquid supply arm 31. Specifically, the liquid supply arm 31 is configured with a clamping piece 34 shown in fig. 2, and the fixing arm 41 is inserted into a fixing hole of the clamping piece 34; the fixed arm 41 is movable in the longitudinal direction of the liquid supply arm 31 to adjust the position of the conditioning disk 42.

In some embodiments, the rear end of the fixed arm 41 is configured with a driving module that can drive the fixed arm 41 to move along the length direction of the liquid supply arm 31, so that the conditioning disk 42 can completely cover the polishing area to maintain a good conditioning effect.

Meanwhile, the present invention also provides a polishing method using the chemical mechanical polishing apparatus 100 shown in fig. 1, fig. 6 is a flowchart of the polishing method, comprising:

s1, loading a wafer by a carrier head 20 and pressing against a polishing pad above a polishing disk 10 to implement chemical mechanical polishing;

specifically, an elastic film provided at the lower part of the carrier head 20 adsorbs a wafer to be polished by negative pressure; the fixed frame 21 shown in fig. 5 drives the carrier head 20 and the whole wafer to move toward the polishing disk 10, so that the wafer to be polished is entirely located on the polishing pad above the polishing disk 10; the carrier head 20 then presses the wafer against the polishing pad to perform chemical mechanical polishing.

S2, the liquid supply assembly 30 supplies polishing liquid to the polishing area, and the online dressing assembly 40 integrated with the liquid supply assembly 30 online dresses the surface of the polishing pad.

Specifically, the liquid supply pivot shaft 33 drives the liquid supply arm 31 to swing toward the polishing disk 10, so that the liquid supply pipe 32 is located above the polishing pad to supply the polishing liquid toward the active area of the wafer; meanwhile, the dressing plate 42 on the fixed arm 41 is pressed against the polishing pad, and the dressing plate 42 can remove accumulated particles above the polishing pad, so that the use performance of the polishing pad is prevented from being influenced by the blocking of the porous microstructure of the polishing pad.

For third generation semiconductor materials, a large amount of tiny particles are generated during polishing; in the existing polishing method, the polishing pad needs to be integrally trimmed after a wafer is processed; at the later stage of the single wafer polishing process, the characteristics of the polishing pad may decrease to affect the material removal rate, which may extend the polishing time of the wafer and affect the polishing efficiency of the wafer.

The polishing method provided by the invention can be used for finishing the polishing pad in real time in the polishing process so as to maintain the characteristics of the polishing pad, ensure the stability of the polishing removal rate and improve the processing efficiency of the wafer.

As an embodiment of the present invention, during polishing, the carrier head 20 can reciprocally rotate with reference to the center of the polishing platen 10, and the in-line dressing assembly 40 follows the carrier head 20 to change the dressing operation position so that the dressing platen 42 of the in-line dressing assembly 40 can cover at least the active area of the wafer. In fig. 1, the movement of the carrier head 20 and the liquid supply assembly 30 is shown using dashed lines; only one carrier head 20 and corresponding movement of the liquid supply assembly 30 is shown in order not to interfere with the clear embodiment of the solution.

Specifically, in the polishing process, the fixing frame 21 shown in fig. 5 drives the carrier head 20 to reciprocally rotate with reference to the center of the fixing frame 21, so as to change the contact area between the wafer loaded by the carrier head 20 and the polishing pad; meanwhile, the in-line conditioning assembly 40 integrated with the conditioning arm 31 follows the carrier head 20 to change the working area of the conditioning disk 42, expanding the conditioning range of the conditioning disk 42. That is, on the premise that the carrier head 20 and the liquid supply arm 31 keep a safe distance, the fixed arm 41 moves towards the moving direction of the carrier head 20, so as to realize online trimming.

Fig. 7 is a schematic view of a chemical mechanical polishing apparatus 100 according to another embodiment of the present invention, where the chemical mechanical polishing apparatus 100 includes:

a polishing pad 10;

a carrier head 20 for loading a wafer to be polished;

the liquid supply assembly 30, the liquid supply assembly 30 corresponds to the bearing head 20 one by one, the liquid supply assembly 30 comprises a liquid supply arm 31, and the liquid supply arm 31 is provided with a plurality of liquid supply pipes 32 for supplying polishing liquid to the polishing pad above the polishing disk 10;

an in-line dressing assembly 40, the in-line dressing assembly 40 being integrated with the liquid supply assembly 30 and being located at a side of the liquid supply arm 31 to dress the surface of the polishing pad in-line;

an offline conditioning assembly 50, the offline conditioning assembly 50 being disposed laterally of the polishing platen 10 to offline condition the polishing pad surface.

In the embodiment of fig. 7, the structure and function of the other components, except for the offline conditioning assembly 50, are similar to those of the corresponding components in the embodiment of fig. 1, and are briefly described below:

specifically, the liquid supply assembly 30 includes a liquid supply pivot shaft 33, and the liquid supply pivot shaft 33 is disposed outside the polishing disk 10; a liquid supply arm 31 is disposed above the liquid supply pivot 33 to drive the liquid supply arm 31 and the online trimming assembly 40 to swing around the liquid supply pivot 33.

Further, the liquid supply arm 31 has an arc structure, extends toward the center of the polishing disk 10 and is located between the adjacent carrier heads 20, and the liquid supply pipes 32 are arranged at intervals along the length direction of the liquid supply arm 31 to supply polishing liquid at different positions of the polishing pad, so that the polishing liquid can fully enter the inside of the carrier heads 20 to participate in the chemical mechanical polishing of the wafer.

The in-line dressing assembly 40 further includes a fixing arm 41 shown in fig. 2, the fixing arm 41 being disposed adjacent to the liquid supply arm 31, an end portion of the fixing arm 41 being provided with a dressing plate 42; the trimming disk 42 is provided at the front end of the fixed arm 41, and the outer shape and size of the trimming disk 42 match the outer shape and size of the liquid supply arm 31.

In fig. 7, the number of the carrying heads 20 is three, and the carrying heads 20 are uniformly distributed below the fixing frame 21; the fixing frame 21 can drive the carrier head 20 to rotate around the central axis, and the liquid supply arm 31 can follow the carrier head 20 to swing around the liquid supply pivot shaft 33, so as to change the positions of the liquid supply pipe 32 on the liquid supply arm 31 and the trimming disc 42 on the fixing arm 41, thereby ensuring the supply of polishing liquid and realizing the trimming operation of the polishing pad.

In fig. 7, the offline conditioning assembly 50 includes a conditioning pivot shaft 51, a conditioning arm 52 is provided above the conditioning pivot shaft 51, and a conditioner 53 is provided at an end of the conditioning arm 52 to condition the polishing pad surface offline.

Further, the dressing pivot shaft 51 is disposed at the outer side of the polishing disk 10, and the dressing pivot shaft 51 is disposed between the adjacent liquid supply pivot shafts 33, and the dresser 53 can be pressed against the polishing pad and perform the dressing operation, wherein the structure and the operation principle of the dresser 53 can be referred to the related description of the dressing apparatus for chemical mechanical polishing in the CN114536221a, and the description is omitted herein.

In addition, the present invention also discloses a polishing method using the chemical mechanical polishing apparatus 100 shown in fig. 7, the polishing method having a flow chart as shown in fig. 8, comprising:

s10, the bearing head 20 loads a wafer and presses against a polishing pad above the polishing disk 10, and the liquid supply assembly 30 supplies polishing liquid to the polishing pad so as to implement chemical mechanical polishing;

s20, during the polishing process, the online dressing assembly 40 is used for dressing the polishing pad;

in the process of dressing the polishing pad in line, the carrier head 20 can be reciprocally rotated with reference to the center of the polishing pad 10, and the in-line dressing assembly 40 moves following the carrier head 20 to change the dressing operation position.

That is, the carrier head 20 and the loaded wafer are driven by the fixing frame 21 to reciprocate with the center of the fixing frame 21 as a reference, and meanwhile, the liquid supply arm 31 of the liquid supply assembly 30 follows the swing with the liquid supply pivot shaft 33 as a reference, so as to change the working area of the trimming disc 42, so that the movable polishing area of the wafer can be fully trimmed, and the polishing characteristics of the polishing pad can be stabilized.

S30, after polishing is completed, the carrier head 20 is away from the polishing pad 10, and the offline conditioning assembly 50 is used to condition the polishing pad.

Specifically, after polishing is completed, the fixing frame 21 carries the carrier head 20 away from the polishing disk 10 to unload the polished wafer, thereby providing space for the offline conditioning assembly 50 to function; meanwhile, the dressing arm 52 swings toward the polishing disk 10 with reference to the dressing pivot shaft 51, and a dresser 53 provided at the front end of the dressing arm 52 acts on the polishing pad to dress the polishing pad surface as a whole.

Since the chemical mechanical polishing apparatus 100 is configured with the in-line dressing assembly 40, it is possible to properly dress the polishing pad during polishing, to shorten the working time of the offline dressing assembly 50, and to improve the overall working efficiency of the chemical mechanical polishing apparatus 100.

It should be noted that the solution/apparatus provided in the present application is mainly applied to chemical mechanical polishing of wafers of third generation semiconductor materials, and may be specifically applied to 4 inch, 6 inch or 8 inch wafers processed by the third generation semiconductor materials, such as 4, 6, 8 inch GaN wafers, or 8 inch SiC wafers.

In addition, because the growth difficulty of the third-generation semiconductor material is higher, the problems of difficult control of a temperature field, slow growth speed, high requirements on good product parameters, large crystal diameter expansion difficulty and the like exist, the wafer size of the third-generation semiconductor material is mainly 6-8 inches, along with the development of technology and the overcoming of the growth problem, the wafer size of the third-generation semiconductor material can be expanded to 12 inches or even more than 12 inches, and the method and the device are also applicable to the scheme/equipment provided by the application and are all within the protection scope of the application.

While embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that: many changes, modifications, substitutions and variations may be made to the embodiments without departing from the spirit and principles of the invention, the scope of which is defined by the claims and their equivalents.

Claims (20)

1. A chemical mechanical polishing apparatus, comprising:

polishing disk;

the bearing head is used for loading a wafer to be polished;

the liquid supply assembly is in one-to-one correspondence with the bearing heads and comprises liquid supply arms, and the liquid supply arms are provided with a plurality of liquid supply pipes for supplying polishing liquid to the polishing pads above the polishing disk;

and the online trimming assembly is integrated with the liquid supply assembly and positioned at the side of the liquid supply arm so as to trim the surface of the polishing pad online.

2. The chemical mechanical polishing apparatus according to claim 1, wherein the number of carrier heads is plural, and the liquid supply arm is disposed between adjacent carrier heads.

3. The chemical mechanical polishing apparatus according to claim 1, wherein the liquid supply arm has an arc-shaped structure extending toward the center of the polishing disk; the liquid supply pipes are arranged at intervals along the length direction of the liquid supply arm.

4. The chemical mechanical polishing apparatus according to claim 1, wherein the in-line conditioning assembly includes a stationary arm disposed adjacent to the liquid supply arm, and a conditioning disk is disposed below the stationary arm.

5. The chemical mechanical polishing apparatus according to claim 4, wherein the conditioning disk is disposed at a front end of the fixed arm, and has a shape and size matching those of the liquid supply arm.

6. The chemical mechanical polishing apparatus according to claim 2, wherein the liquid supply assembly includes a liquid supply pivot shaft disposed outside the polishing platen; the liquid supply arm is arranged above the liquid supply pivot shaft, and the liquid supply arm and the online trimming assembly can swing around the liquid supply pivot shaft.

7. The chemical mechanical polishing apparatus according to claim 6, wherein the number of the carrier heads is three, and the carrier heads are uniformly distributed below the fixed frame; the fixing frame can drive the bearing head to rotate reciprocally around the center of the bearing head, and the liquid supply arm follows the bearing head to swing around the liquid supply pivot shaft.

8. A chemical mechanical polishing apparatus as recited in claim 4, wherein the fixed arm is detachably connected to a side of the liquid supply arm.

9. The chemical mechanical polishing apparatus according to claim 8, wherein the liquid supply arm is provided with a clamping member, and the fixed arm is provided to the clamping member; the fixed arm is movable along the length direction of the liquid supply arm to adjust the position of the conditioning disk.

10. A polishing method, characterized by using the chemical mechanical polishing apparatus according to any one of claims 1 to 9, comprising:

s1, loading a wafer by a bearing head and pressing a polishing pad above a polishing disk to implement chemical mechanical polishing;

s2, supplying polishing liquid to the polishing area by the liquid supply assembly, and online dressing the surface of the polishing pad by the online dressing assembly integrated with the liquid supply assembly.

11. The polishing method as recited in claim 10 wherein the carrier head is capable of reciprocating with respect to a center of the polishing platen, and the on-line dressing assembly follows the carrier head to change a dressing operation position.

12. A chemical mechanical polishing apparatus, comprising:

polishing disk;

the bearing head is used for loading a wafer to be polished;

the liquid supply assembly is in one-to-one correspondence with the bearing heads and comprises liquid supply arms, and the liquid supply arms are provided with a plurality of liquid supply pipes for supplying polishing liquid to the polishing pads above the polishing disk;

the online trimming assembly is integrated on the liquid supply assembly and positioned at the side of the liquid supply arm so as to trim the surface of the polishing pad online;

and the off-line dressing assembly is arranged at the side of the polishing disc so as to finish the surface of the polishing pad off-line.

13. The chemical mechanical polishing apparatus according to claim 12, wherein the liquid supply assembly includes a liquid supply pivot shaft disposed outside the polishing platen; and a liquid supply arm is arranged above the liquid supply pivot shaft, and the liquid supply arm and the online trimming assembly swing around the liquid supply pivot shaft.

14. The chemical mechanical polishing apparatus according to claim 13, wherein the number of the carrier heads is three, and the carrier heads are uniformly distributed below the fixed frame; the fixing frame can drive the bearing head to rotate reciprocally around the center of the bearing head, and the liquid supply arm follows the bearing head to swing around the liquid supply pivot shaft.

15. The chemical mechanical polishing apparatus of claim 13, wherein the off-line conditioning assembly includes a conditioning pivot shaft having a conditioning arm disposed thereon, an end of the conditioning arm configured with a conditioner to condition the polishing pad surface off-line.

16. The chemical mechanical polishing apparatus according to claim 15, wherein the dressing pivot is disposed outside the polishing platen and between adjacent liquid supply pivot shafts, the dresser being capable of pressing against the polishing pad to perform the dressing operation.

17. The chemical mechanical polishing apparatus according to claim 13, wherein the liquid supply arm has an arc-shaped structure extending toward the center of the polishing platen and located between adjacent carrier heads; the liquid supply pipes are arranged at intervals along the length direction of the liquid supply arm.

18. The chemical mechanical polishing apparatus according to claim 17, wherein the in-line dressing assembly includes a fixed arm disposed adjacent to the liquid supply arm, an end of the fixed arm being configured with a dressing disk; the trimming disc is arranged at the front end of the fixed arm, and the outer shape and the size of the trimming disc are matched with those of the liquid supply arm.

19. A polishing method, characterized by using the chemical mechanical polishing apparatus according to any one of claims 12 to 18, comprising:

s10, a carrying head loads a wafer and presses against a polishing pad above a polishing disk, and a liquid supply assembly supplies polishing liquid to the polishing pad so as to implement chemical mechanical polishing;

s20, in the polishing process, an online trimming assembly is used for trimming the polishing pad;

and S30, after polishing is finished, the bearing head is far away from the polishing disc, and the offline dressing assembly is used for dressing the polishing pad.

20. The polishing method as recited in claim 19 wherein the carrier head is capable of reciprocating with respect to a center of the polishing platen, and the on-line dressing assembly follows the carrier head to change a dressing operation position.