WO2022143526A1

WO2022143526A1 - Linear polishing machine

Info

Publication number: WO2022143526A1
Application number: PCT/CN2021/141632
Authority: WO
Inventors: 吴孟谕
Original assignee: 广州集成电路技术研究院有限公司
Priority date: 2020-12-29
Filing date: 2021-12-27
Publication date: 2022-07-07
Also published as: CN114683164A

Abstract

A linear polishing machine, comprising: a polishing disc (200) for fixing a member (100) to be polished, a power mechanism located above the polishing disc (200), and a grinding pad (330) in transmission connection with the power mechanism; wherein the power mechanism is used for driving the grinding pad (330), so that the grinding pad (330) directly contacts and grinds said member (100). The linear polishing machine of the present invention has a novel design and high practicability.

Description

A linear polishing machine

technical field

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

Background technique

Chemical mechanical polishing or planarization (CMP) is a process that combines chemical and mechanical forces for surface planarization. In the CMP process, an abrasive and corrosive chemical slurry is used in conjunction with the polishing pad and the ring; wherein, the diameter of the polishing pad is usually larger than that of the workpiece to be polished.

There are two main types of existing chemical mechanical polishing equipment. One of the chemical mechanical polishing equipment includes a polishing head, a polishing disc, a polishing pad organizer, and a fluid pipeline. The polishing head spins at its center, and the lower end clamps the wafer through a ring (Retaining Ring); a polishing pad is provided on the polishing disc, as shown in Figures 1 and 2. The working process is as follows: the polishing head spins and presses the wafer, the polishing disc drives the polishing pad to spin, and the fluid pipeline injects the polishing liquid, so that the wafer is ground and polished on the polishing pad by chemical and mechanical methods. At the same time, the pad organizer cleans the pad by its own motion along with deionized water. Another chemical mechanical polishing apparatus includes a polishing head, a polishing disc, a pad organizer, a fluid conduit, and a linear transfer mechanism. The polishing head spins with its center, and the lower end clamps the wafer through the clamping ring; the polishing pad is arranged on the periphery of the linear conveying structure.

technical problem

The above two chemical mechanical polishing apparatuses have the following problems: 1) Both chemical mechanical polishing apparatuses clamp the face-down wafer by the polishing head, and grind the wafer by the rotation of the polishing head. However, in different radii of the wafer, due to the different linear and angular velocities, the grinding speed at the outer edge of the wafer is the largest, and the grinding speed at the center is the smallest, which is likely to cause poor grinding consistency from the center of the wafer to the edge. 2) Both chemical mechanical polishing equipments need to set an air flow channel in the polishing disc, so that during the polishing process, the polishing pad is lifted up by the upward air flow, so that the wafer is in close contact with the polishing pad. However, due to the air flow and the upward pressure of the polishing pad, it is difficult to ensure the consistency, and the wafer and the polishing pad are not in perfect contact, which also results in poor polishing consistency on the wafer surface. 3) In the two chemical mechanical polishing equipments, the polishing pad organizer cleans the polishing pad by spinning and abutting the polishing pad, the contact area is small, the cleaning efficiency is low, and the cleaning effect consistency is poor.

technical solutions

Aiming at the above technical problems, the present invention proposes a linear polishing machine.

The present invention proposes the following technical solutions:

The invention provides a linear polishing machine, which includes a polishing disc for fixing a workpiece to be polished, a power mechanism located above the polishing disc, and a grinding pad drivingly connected with the power mechanism; the power mechanism is used to drive the grinding pad to make the grinding pad Direct contact and grinding of the part to be polished.

In the above-mentioned linear polishing machine of the present invention, the grinding pad is in the shape of an endless belt; the power mechanism includes a plurality of rollers; the plurality of rollers are all penetrated in the grinding pad, and the grinding pad is propped up cooperatively so as to be rotated by the respective rollers. The grinding pad is driven to rotate in a matched manner, so that the workpiece to be polished is linearly polished through the rotation of the grinding pad.

In the above-mentioned linear polishing machine of the present invention, the rollers are liftable rollers, which are used to exert downward force on the workpiece to be polished by means of the polishing pad.

In the above-mentioned linear polishing machine of the present invention, the power mechanism further comprises a polishing pad organizer abutting against the polishing pad and used for cleaning the polishing pad;

The polishing pad organizer spans the polishing pad; the spanning direction of the polishing pad organizer is perpendicular to the driving direction of the polishing pad.

In the above-mentioned linear polishing machine of the present invention, the power mechanism further comprises a frame, and a ring member mounted on the frame and used to cover the workpiece to be polished to prevent the workpiece to be polished from sliding.

In the above-mentioned 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 above-mentioned linear polishing machine of the present invention, a lifting mechanism for lifting and lowering the workpiece to be polished is installed on the polishing disc.

In the above-mentioned linear polishing machine of the present invention, a polishing head is also included; the polishing head includes the power mechanism and a polishing pad;

The linear polishing machine also includes an annular track; there are multiple polishing heads, and the multiple polishing heads are respectively directly or indirectly slidably mounted on the annular track;

A plurality of polishing discs are arranged, and the plurality of polishing discs are all arranged below the annular track.

The linear polishing machine also includes a linear track; there are multiple polishing heads, and the multiple polishing heads are respectively directly or indirectly slidably mounted on the linear track;

A plurality of polishing discs are arranged, and the plurality of polishing discs are all arranged below the linear track.

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

beneficial effect

The linear polishing machine of the invention can directly reduce the non-uniformity between the center and the edge of the workpiece to be polished, and can meet the high-density requirements of multiple polishing heads through the annular track and the linear track, and the multiple polishing heads can be flexibly arranged. The polishing head can be equipped with hard abrasive pads, soft abrasive pads and brushes respectively to meet the needs of polishing schemes or processes. At the same time, the linear polishing machine of the present invention can be designed to be smaller than the conventional polishing machine. The linear polishing machine of the invention has novel design and strong practicability.

Description of drawings

Below in conjunction with accompanying drawing, the present invention is further described:

Fig. 1 shows the structural representation of a kind of existing CMP equipment;

FIG. 2 shows a schematic side view of the conventional CMP apparatus shown in FIG. 1 .

FIG. 3 shows a schematic structural diagram of a polishing head and a polishing disc of a linear polishing machine for chemical mechanical polishing (CMP);

FIG. 4 shows a schematic structural diagram of the linear polishing machine according to the first preferred embodiment of the present invention;

FIG. 5 shows a schematic structural diagram of a linear polishing machine according to the second preferred embodiment of the present invention;

FIG. 6 shows a reference diagram of the use state of the polishing disk and the wafer robot of the linear polishing machine shown in FIGS. 4 and 5 .

Detailed ways

In order to make the technical solution, technical purpose and technical effect of the invention clearer, so that those skilled in the art can understand and implement the present invention, the present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments.

As shown in FIG. 3 , FIG. 3 shows a schematic structural diagram of a polishing head and a polishing disc of a linear polishing machine used for chemical mechanical polishing CMP. The linear polishing machine includes a polishing disk 200 for fixing the workpiece 100 to be polished, a power mechanism located above the polishing disk 200, and a polishing pad 330 connected to the power mechanism; the power mechanism is used to drive the polishing pad 330 to make the polishing pad 330 directly contacts and grinds the workpiece 100 to be polished.

In this embodiment, the object to be polished 100 is a wafer to be polished.

The above-mentioned technical solution is a basic solution. The polishing disc 200 is used to fix the workpiece 100 to be polished, and the polishing pad 330 directly contacts and grinds the workpiece 100 to be polished, so that the thickness of the workpiece 100 to be polished can be kept uniform.

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

The grinding pad 330 is in the shape of an endless belt; the power mechanism includes a plurality of rollers 320 that are parallel to each other; the plurality of rollers 320 are all penetrated in the grinding pad 330, and the grinding pad 330 is cooperatively stretched, and is used to cooperate with each other by rotating The polishing pad 330 is driven to rotate, so that the workpiece 100 to be polished is linearly polished through the rotation of the polishing pad 330 .

Wherein, the roller 320 is a roller that can be independently controlled to rise and fall, and is used to exert downward force on the object to be polished 100 through the abrasive pad 330 . In this embodiment, the polishing head 300 can be raised and lowered, so that the roller can be raised and lowered.

Further, the power mechanism further includes a polishing pad organizer 340 arranged in parallel with the roller 320 and abutting with the polishing pad 330 for cleaning the polishing pad 330 . The polishing pad organizer 340 spans the polishing pad 330 ; the spanning direction of the polishing pad organizer 340 is perpendicular to the driving direction of the polishing pad 330 . The function of the polishing pad organizer 340 is to clean the polishing pad 330. By being perpendicular to the transmission direction of the polishing pad, it has the technical effects of high cleaning efficiency and good consistency. Preferably, in this embodiment, the number of polishing pad organizers 340 may be one or more.

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

Further, the power mechanism further includes a frame 360 and a ring member 310 mounted on the frame 360 and used to cover the workpiece 100 to be polished to prevent the workpiece 100 from sliding; a plurality of rollers 320 are respectively rotatably installed on the machine On the frame 360; the polishing pad organizer 340 is rotatably arranged on the frame 360.

Further, the polishing disc 200 is a horizontally movable mechanism for adjusting the position of the workpiece 100 to be polished. Here, the fixing method of the workpiece to be polished 100 and the polishing disk 200 may be a suction cup method, or a receiving member may be provided on the polishing disk, and the receiving member includes a groove for accommodating the workpiece to be polished 100 .

Further, the linear polishing machine further includes a first guide tube 400 for applying deionized water and/or chemical slurry to the polishing pad 330; wherein the chemical slurry may be abrasive and corrosive; in addition, the first guide There may be multiple tubes 400 .

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

As shown in FIG. 4 , FIG. 4 shows a schematic structural diagram of a linear polishing machine according to the first preferred embodiment of the present invention. The linear polishing machine further includes an annular track 500; there are multiple polishing heads 300, and the multiple polishing heads 300 are directly or indirectly slidably mounted on the annular track 500 through respective racks 360 (not shown in the figure);

A plurality of polishing discs 200 are provided, and the plurality of polishing discs 200 are arranged below the annular track 500;

In FIG. 4 , a plurality of polishing heads 300 slide on the annular track 500 respectively, so that the effect of polishing the workpiece 100 to be polished on the same polishing disc 200 by different polishing heads 300 can be achieved.

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

As shown in FIG. 5 , FIG. 5 shows a schematic structural diagram of a linear polishing machine according to the second preferred embodiment of the present invention. The linear polishing machine further includes a linear track 700; there are multiple polishing heads 300, and the multiple polishing heads 300 are directly or indirectly slidably mounted on the linear track 700 through their respective racks 360 (not shown in the figure);

A plurality of polishing discs 200 are provided, and the plurality of polishing discs 200 are arranged below the linear track 700;

In FIG. 5 , a plurality of polishing heads 300 slide on the linear track 700 respectively, so that the effect of polishing the workpiece 100 to be polished on the same polishing disc 200 by different polishing heads 300 can be achieved.

In the prior art solution, the chemical mechanical polishing equipment using a combination of multiple polishing heads often has an accident that the whole machine is shut down due to the failure of one of the polishing heads. A downtime in the polishing head resulted in a production stoppage. It will be appreciated that there may be more than two linear tracks (700).

Generally speaking, in the prior art, a single wafer needs to undergo various polishing processes, that is, using different polishing pads 330 , which is troublesome and time-consuming to replace. In the case where the linear polishing machine includes a plurality of polishing heads 300, the polishing pads 330 can be of different types to meet the requirements of polishing and improve the processing capacity and efficiency of the equipment.

In this embodiment, the linear polishing machine further includes a wafer robot 600 for moving the workpiece 100 to be polished.

Further, as shown in FIG. 6 , in this embodiment, further, a lifting mechanism 210 for lifting and lowering the workpiece 100 to be polished is installed on the polishing disc 200 . The lift mechanism 210 includes a retractable support that can be embedded in the polishing disc 200 . When the wafer is fixed, the retractable support is retracted downward so that the backside of the wafer abuts the polishing pad 200 . When the wafer is removed, the retractable support extends upward to keep the wafer away from the polishing pad 200 for removal by the wafer robot 600 .

In addition, in the prior art, the machine of the chemical mechanical polishing equipment occupies an excessively large area, and the two chemical mechanical polishing equipment described in the background art need to ensure that the radius of the polishing disc and the grinding pad is much larger than the radius of the wafer, so that the Grinding effect can be achieved. With the technical solution of the present invention, by fixing the workpiece 100 to be polished and the moving grinding pad 330, it is only necessary to ensure that the polishing disc can provide a support solution to fix the wafer, that is, this solution greatly reduces the occupied area of the polishing disc and saves space . The linear polishing machine of the present invention can directly reduce the non-uniformity between the center and the edge of the workpiece to be polished, and can meet the high-density requirements of multiple polishing heads through the annular track and the linear track, and the multiple polishing heads can be flexibly arranged. The polishing head can be equipped with hard abrasive pads, soft abrasive pads and brushes respectively to meet the needs of polishing schemes or processes. At the same time, the linear polishing machine of the present invention can be designed to be smaller than the conventional polishing machine. The linear polishing machine of the invention has novel design and strong practicability.

The embodiments of the present invention have been described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific embodiments, which are merely illustrative rather than restrictive. Under the inspiration of the present invention, without departing from the scope of protection of the present invention and the claims, many forms can be made, which all belong to the protection of the present invention.

Claims

A linear polishing machine, characterized in that it comprises a polishing disc (200) for fixing a workpiece (100) to be polished, a power mechanism located above the polishing disc (200), and a grinding pad (330) drivingly connected with the power mechanism; The power mechanism is used for driving the polishing pad (330), so that the polishing pad (330) directly contacts and grinds the workpiece (100) to be polished.
The linear polishing machine according to claim 1, characterized in that, the grinding pad (330) is in the shape of an endless belt; the power mechanism comprises a plurality of rollers (320); 330), the grinding pad (330) is propped up cooperatively, so as to drive the grinding pad (330) to rotate through the respective rotation, so that the workpiece (100) to be polished is linearly polished by the rotation of the grinding pad (330).
The linear polishing machine according to claim 2, characterized in that, the roller (320) is a liftable roller, and is used for exerting downward force on the object to be polished (100) by the abrasive pad (330).
The linear polishing machine according to any one of claims 1 to 3, wherein the power mechanism further comprises a polishing pad organizer (340) abutting against the polishing pad (330) and used for cleaning the polishing pad (330). ;

The polishing pad organizer (340) spans the polishing pad (330); the spanning direction of the polishing pad organizer (340) is perpendicular to the driving direction of the polishing pad (330).
The linear polishing machine according to any one of claims 1 to 3, wherein the power mechanism further comprises a frame (360), and is mounted on the frame (360) and used to cover the workpiece (100 to be polished) ) to prevent the sliding of the to-be-polished (100) ring (310).
The linear polishing machine according to any one of claims 1 to 3, characterized in that, the polishing disc (200) is a horizontally movable mechanism for adjusting the position of the workpiece (100) to be polished.
The linear polishing machine according to any one of claims 1 to 3, characterized in that, a lifting mechanism (210) for lifting and lowering the workpiece (100) to be polished is installed on the polishing disc (200).
The linear polishing machine according to any one of claims 1 to 3, further comprising a polishing head (300); the polishing head (300) comprising the power mechanism and a grinding pad (330);

The linear polishing machine further comprises an annular track (500); there are a plurality of polishing heads (300), and the plurality of polishing heads (300) are respectively directly or indirectly slidably mounted on the annular track (500);

A plurality of polishing discs (200) are provided, and the plurality of polishing discs (200) are all arranged below the annular track (500).
The linear polishing machine according to any one of claims 1 to 3, further comprising a polishing head (300); the polishing head (300) comprising the power mechanism and a grinding pad (330);

The linear polishing machine further includes a linear track (700); there are multiple polishing heads (300), and the multiple polishing heads (300) are respectively directly or indirectly slidably mounted on the linear track (700);

A plurality of polishing discs (200) are provided, and the plurality of polishing discs (200) are all arranged below the linear track (700).
The linear polishing machine according to claim 9, characterized in that, the linear polishing machine is provided with at least two linear tracks (700).