CN114683164A

CN114683164A - Linear polishing machine

Info

Publication number: CN114683164A
Application number: CN202011592264.2A
Authority: CN
Inventors: 吴孟谕
Original assignee: Guangzhou Integrated Circuit Technology Research Institute Co ltd
Current assignee: Guangzhou Integrated Circuit Technology Research Institute Co ltd
Priority date: 2020-12-29
Filing date: 2020-12-29
Publication date: 2022-07-01
Also published as: WO2022143526A1

Abstract

A linear polisher comprises a polishing disc (200) for fixing a piece (100) to be polished, a power mechanism positioned above the polishing disc (200) and a grinding pad (330) in transmission connection with the power mechanism; the power mechanism is used for driving the grinding pad (330) so that the grinding pad (330) directly contacts and grinds the piece (100) to be polished. The linear polishing machine is novel in design and high in practicability.

Description

Linear polishing machine

Technical Field

The invention relates to the technical field of wafer polishing, in particular to a linear polishing machine.

Background

Chemical mechanical polishing or planarization (CMP) is a process that combines chemical and mechanical forces for surface planarization. In the CMP process, chemical slurry with abrasive property and corrosive property is used in combination with a polishing pad and a ring-shaped member; wherein the polishing pad typically has a diameter larger than the member to be polished.

The existing chemical mechanical polishing equipment mainly comprises two types, wherein one type of chemical mechanical polishing equipment comprises a polishing head, a polishing disk, a grinding pad finisher and a fluid pipeline. The polishing head spins around the center of the polishing head, and the lower end of the polishing head clamps the wafer through a Ring-shaped piece (Retaining Ring); the polishing pad is provided with a polishing pad as shown in fig. 1 and 2. The working process is as follows: the polishing head spins and presses the wafer downwards, the polishing disk drives the polishing pad to spin, and the fluid pipeline injects polishing liquid to enable the wafer to be polished on the polishing pad in a chemical mode and a mechanical mode. Meanwhile, the polishing pad conditioner cleans the polishing pad through its own motion and deionized water. Another chemical mechanical polishing apparatus includes a polishing head, a polishing disk, an abrasive pad conditioner, a fluid conduit, and a linear transport mechanism. The polishing head spins by the center thereof, and the lower end clamps the wafer through the clamping ring; the polishing pad is disposed at the periphery of the linear transport structure.

The two chemical mechanical polishing devices have the following problems: 1) in both chemical mechanical polishing apparatuses, a wafer with a front surface facing downward is held by a polishing head, and the wafer is ground by the rotation of the polishing head. However, in the areas with different radii of the wafer, due to the difference between the linear velocity and the angular velocity, the polishing speed at the outer edge of the wafer is the largest, and the polishing speed at the center is the smallest, which easily causes the poor uniformity of polishing from the center to the edge of the wafer. 2) In both types of chemical mechanical polishing apparatuses, an air flow channel is required to be arranged in the polishing disk, so that the polishing pad is lifted upwards by upward air flow during the polishing process, so that the wafer is in close contact with the polishing pad. However, since the uniformity of the gas flow and the upward pressure of the polishing pad are difficult to be ensured, the wafer and the polishing pad are not in perfect contact, which also results in poor uniformity of polishing on the wafer surface. 3) In two kinds of chemical mechanical polishing equipment, the grinding pad reorganizer carries out the grinding pad clearance through spin and butt grinding pad, and area of contact is little, and the clearance is inefficient, and the clearance effect uniformity is poor.

Disclosure of Invention

The invention provides a linear polishing machine aiming at the technical problems.

The invention provides the following technical scheme:

the invention provides a linear polishing machine, which comprises a polishing disk for fixing a piece to be polished, a power mechanism positioned above the polishing disk and a grinding pad in transmission connection with the power mechanism, wherein the polishing disk is used for fixing the piece to be polished; the power mechanism is used for driving the grinding pad so as to enable the grinding pad to directly contact and grind the piece to be polished.

In the linear polishing machine of the invention, the polishing pad is in a ring belt shape; the power mechanism comprises a plurality of rollers; the rollers are arranged in the grinding pad in a penetrating mode, cooperatively prop the grinding pad open, and are used for driving the grinding pad to rotate through respective rotation coordination, so that the to-be-polished piece is linearly polished through the rotation of the grinding pad.

In the above linear polishing machine of the present invention, the rollers are liftable rollers for applying downward force to the workpiece to be polished by the polishing pad.

In the linear polishing machine of the invention, the power mechanism further comprises a grinding pad collator which is abutted against the grinding pad and used for cleaning the grinding pad;

the polishing pad collator spans across the polishing pad; the crossing direction of the polishing pad collator is vertical to the transmission direction of the polishing pad.

In the linear polishing machine of the invention, the power mechanism further comprises a frame and a ring-shaped member which is arranged on the frame and used for covering the member to be polished so as to prevent the member to be polished from sliding.

In the above linear polishing machine of the present invention, the polishing disc is a horizontally movable mechanism for adjusting the position of the workpiece to be polished.

In the linear polishing machine of the invention, the polishing disk is provided with the lifting mechanism for lifting the piece to be polished.

The linear polishing machine further comprises a polishing head; the polishing head comprises the power mechanism and a polishing pad;

the linear polisher also includes an annular track; the plurality of polishing heads are respectively and directly or indirectly slidably arranged on the annular track;

the polishing dish is provided with a plurality ofly, and a plurality of polishing dishes all set up in the below of circular orbit.

the linear polishing machine also comprises a linear track; the polishing heads are respectively and directly or indirectly slidably arranged on the linear track;

the polishing dish is provided with a plurality ofly, and a plurality of polishing dishes all set up in linear orbit's below.

In the above linear polishing machine of the present invention, the linear polishing machine is provided with at least two linear rails.

The linear polishing machine can directly reduce the nonuniformity between the center and the edge of a workpiece to be polished, can meet the high-flux requirement of a plurality of polishing heads through the annular track and the linear track, can be flexibly arranged, and can respectively configure a hard polishing pad, a soft polishing pad and a brush for different polishing heads, thereby meeting the requirement of a polishing scheme or process. At the same time, the linear polisher of the present invention can be designed smaller than conventional polishers. The linear polishing machine is novel in design and high in practicability.

Drawings

The invention is further described below with reference to the accompanying drawings:

FIG. 1 is a schematic view showing a structure of a conventional CMP apparatus;

fig. 2 is a schematic side view of the conventional CMP apparatus shown in fig. 1.

FIG. 3 is a schematic view showing a structure of a polishing head and a polishing disk of a linear polisher for Chemical Mechanical Polishing (CMP);

FIG. 4 is a schematic structural view showing a linear polisher according to a first preferred embodiment of the present invention;

FIG. 5 is a schematic structural view showing a linear polisher according to a second preferred embodiment of the present invention;

fig. 6 shows a use state reference diagram of the polishing pad and the wafer robot of the linear polisher shown in fig. 4 and 5.

Detailed Description

In order to make the technical solutions, technical objects, and technical effects of the present invention clearer so as to enable those skilled in the art to understand and implement the present invention, the present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

As shown in fig. 3, fig. 3 is a schematic view showing a structure of a polishing head and a polishing disk of a linear polisher for chemical mechanical polishing CMP. The linear polishing machine comprises a polishing disk 200 for fixing a piece 100 to be polished, a power mechanism positioned above the polishing disk 200 and a grinding pad 330 in transmission connection with the power mechanism; the power mechanism is used for driving the polishing pad 330, so that the polishing pad 330 directly contacts and polishes the to-be-polished piece 100.

In the present embodiment, the workpiece 100 to be polished is a wafer to be polished.

The technical scheme is a basic scheme, the polishing disc 200 is used for fixing the piece to be polished 100, and the polishing pad 330 is used for directly contacting and polishing the piece to be polished 100, so that the thickness of the piece to be polished 100 can be kept to be uniform.

Further, the linear polisher further includes a polishing head 300; the polishing head 300 includes a power mechanism and a polishing pad 330;

the polishing pad 330 has a ring-shaped belt shape; the power mechanism comprises a plurality of rollers 320 parallel to each other; the plurality of rollers 320 are all arranged in the grinding pad 330 in a penetrating manner, cooperatively prop the grinding pad 330 open, and are used for driving the grinding pad 330 to rotate through respective rotation coordination, so that the to-be-polished piece 100 is linearly polished through the rotation of the grinding pad 330.

The rollers 320 are independently controlled to move up and down, and are used for applying a downward force to the polishing article 100 through the polishing pad 330. In this embodiment, the polishing head 300 can be lifted, and the roller can be lifted.

Further, the power mechanism further includes a polishing pad conditioner 340 disposed parallel to the roller 320 and abutting against the polishing pad 330 for cleaning the polishing pad 330. A polishing pad conditioner 340 spanning the polishing pad 330; the cross direction of the polishing pad conditioner 340 is perpendicular to the driving direction of the polishing pad 330. The polishing pad conditioner 340 is used for cleaning the polishing pad 330, and has the technical effects of high cleaning efficiency and good consistency by being vertical to the transmission direction of the polishing pad. Preferably, in the present embodiment, the number of the polishing pad conditioner 340 may be one or more.

Further, the polishing pad conditioner 340 is a rotating shaft with a cleaning part; the cleaning part is sleeved on the rotating shaft.

Further, the power mechanism further comprises a frame 360, and a ring member 310 mounted on the frame 360 and used for covering the member to be polished 100 to prevent the member to be polished 100 from sliding; a plurality of rollers 320 are rotatably mounted on the frame 360, respectively; the polishing pad conditioner 340 is rotatably disposed on the frame 360.

Further, the polishing disk 200 is a horizontally movable mechanism for adjusting the position of the member to be polished 100. Here, the member to be polished 100 and the polishing plate 200 may be fixed by a suction cup, or a receiving member including a groove for receiving the member to be polished 100 may be provided on the polishing plate.

Further, the linear polisher further includes a first guide pipe 400 for applying deionized water and/or chemical slurry onto the polishing pad 330; wherein the chemical slurry may be abrasive and corrosive; in addition, the first guide pipe 400 may be plural.

Further, the polishing head 300 further includes a second guide pipe 350 mounted on the ring member 310 for applying deionized water to the member to be polished 100.

As shown in fig. 4, fig. 4 is a schematic structural view illustrating a linear polisher according to a first preferred embodiment of the present invention. The linear polisher also includes an annular track 500; a plurality of polishing heads 300, the plurality of polishing heads 300 being slidably mounted on the ring-shaped track 500 directly or indirectly via respective racks 360 (not shown);

a plurality of polishing disks 200 are arranged, and the plurality of polishing disks 200 are arranged below the annular track 500;

in fig. 4, a plurality of polishing heads 300 respectively slide on the circular rails 500, so that different polishing heads 300 can polish the workpiece 100 to be polished on the same polishing disk 200.

Further, in the present embodiment, the linear polisher further includes a wafer robot 600 for moving the workpiece 100 to be polished.

As shown in fig. 5, fig. 5 is a schematic structural view illustrating a linear polisher according to a second preferred embodiment of the present invention. The linear polisher also includes a linear track 700; a plurality of polishing heads 300, the plurality of polishing heads 300 being slidably mounted on the linear track 700 directly or indirectly via respective racks 360 (not shown);

a plurality of polishing disks 200 are arranged, and the plurality of polishing disks 200 are arranged below the linear track 700;

in fig. 5, a plurality of polishing heads 300 respectively slide on the linear rails 700, so that different polishing heads 300 can polish the workpiece 100 to be polished on the same polishing disk 200.

In the prior art, the chemical mechanical polishing equipment adopting a combination of a plurality of polishing heads often has the accident that the whole machine stops production due to the fault of one polishing head, and in order to avoid the accident, two linear tracks 700 can be provided, so that the production stop caused by the breakdown of one polishing head is prevented. It is understood that the linear track (700) may be more than two.

Generally, a single wafer of the prior art requires multiple polishing processes, i.e., different polishing pads 330, which is cumbersome and time-consuming to replace. In the case where the linear polisher includes a plurality of polishing heads 300, the polishing pads 330 may be of different types to meet the polishing requirements and improve the throughput and efficiency of the apparatus.

In the present embodiment, the linear polisher further includes a wafer robot 600 for moving the workpiece 100 to be polished.

Further, as shown in fig. 6, in the present embodiment, further, a lifting mechanism 210 for lifting the member to be polished 100 is mounted on the polishing platen 200. The lift mechanism 210 includes a retractable support that may be embedded in the polishing platen 200. When the wafer is held, the retractable support is retracted downward so that the back of the wafer abuts the polishing platen 200. When the wafer is removed, the retractable support extends upward to move the wafer away from the polishing platen 200 for removal by the wafer robot 600.

In addition, in the prior art, the floor area of the chemical mechanical polishing apparatus is too large, and both the two types of chemical mechanical polishing apparatuses described in the background art need to ensure that the radius of the polishing disk and the polishing pad is much larger than the radius of the wafer, so as to achieve the polishing effect. By adopting the technical scheme of the invention, the polishing disc can be supported to fix the wafer only by fixing the to-be-polished piece 100 and the movable grinding pad 330, namely, the scheme greatly reduces the occupied area of the polishing disc and saves the space. The linear polishing machine can directly reduce the nonuniformity between the center and the edge of a piece to be polished, can meet the high-flux requirement of a plurality of polishing heads through the annular track and the linear track, can be flexibly arranged, and can respectively configure a hard polishing pad, a soft polishing pad and a brush for different polishing heads, thereby meeting the requirements of polishing schemes or processes. Also, the linear polisher of the present invention can be designed smaller than conventional polishers. The linear polishing machine is novel in design and high in practicability.

While the present invention has been described with reference to the embodiments shown in the drawings, the present invention is not limited to the embodiments, which are illustrative and not restrictive, and it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. The linear polishing machine is characterized by comprising a polishing disk (200) for fixing a piece (100) to be polished, a power mechanism positioned above the polishing disk (200) and a grinding pad (330) in transmission connection with the power mechanism; the power mechanism is used for driving the grinding pad (330) so that the grinding pad (330) directly contacts and grinds the piece (100) to be polished.

2. The linear polisher of claim 1, where the polishing pad (330) is in the form of an annular band; the power mechanism comprises a plurality of rollers (320); the rollers (320) are arranged in the grinding pad (330) in a penetrating manner, cooperatively prop the grinding pad (330) open, and are used for driving the grinding pad (330) to rotate through respective rotation coordination, so that the to-be-polished piece (100) is linearly polished through the rotation of the grinding pad (330).

3. The linear polisher of claim 2, wherein the rollers (320) are liftable rollers for applying a force downward on the workpiece (100) to be polished by the polishing pad (330).

4. The linear polishing machine according to any one of claims 1 to 3, wherein the power mechanism further comprises a polishing pad collator (340) abutting against the polishing pad (330) for cleaning the polishing pad (330);

a polishing pad conditioner (340) spanning the polishing pad (330); the transverse direction of the polishing pad collator (340) is perpendicular to the transmission direction of the polishing pad (330).

5. The linear polisher according to any one of claims 1 to 3, wherein the power mechanism further comprises a frame (360), and a ring member (310) mounted on the frame (360) for covering the member to be polished (100) to prevent the member to be polished (100) from sliding.

6. The linear polisher according to any one of claims 1 to 3, wherein the polishing disk (200) is a horizontally movable mechanism for adjusting the position of the object (100) to be polished.

7. The linear polisher according to any one of claims 1 to 3, wherein the polishing disk (200) is provided with a lifting mechanism (210) for lifting and lowering the workpiece (100) to be polished.

8. The linear polisher according to any one of claims 1 to 3 further comprising a polishing head (300); the polishing head (300) comprises the power mechanism and a polishing pad (330);

the linear polisher also includes an annular track (500); the polishing heads (300) are multiple, and the multiple polishing heads (300) are respectively and directly or indirectly slidably mounted on the annular track (500);

the polishing discs (200) are arranged in plurality, and the plurality of polishing discs (200) are arranged below the annular rail (500).

9. The linear polisher according to any one of claims 1 to 3 further comprising a polishing head (300); the polishing head (300) comprises the power mechanism and a polishing pad (330);

the linear polisher also includes a linear track (700); the polishing heads (300) are multiple, and the multiple polishing heads (300) are respectively and directly or indirectly slidably mounted on the linear track (700);

the polishing discs (200) are arranged in plurality, and the plurality of polishing discs (200) are arranged below the linear track (700).

10. The linear polisher according to claim 9, characterized in that the linear polisher is provided with at least two linear rails (700).