CN216371665U

CN216371665U - Chemical mechanical polishing equipment

Info

Publication number: CN216371665U
Application number: CN202122157805.5U
Authority: CN
Inventors: 曹秉霞; 郭伟
Original assignee: Guangzhou Yuexin Semiconductor Technology Co Ltd
Current assignee: Yuexin Semiconductor Technology Co ltd
Priority date: 2021-09-07
Filing date: 2021-09-07
Publication date: 2022-04-26
Anticipated expiration: 2031-09-07

Abstract

The utility model provides a chemical mechanical polishing device, comprising: the conveying device is used for receiving the wafer to be ground and unloading the ground wafer; the grinding platform is used for grinding the wafer to be ground; the mounting frame rotates to drive the grinding head to the grinding platform to grind the wafer to be ground, and after the grinding is finished, the mounting frame rotates to drive the grinding head to the conveying device to unload the ground wafer; the grinding head comprises a female head and at least two sub heads, the female head and all the sub heads are connected through a gear, all the sub heads are used for simultaneously sucking a wafer to be ground from the conveying device respectively, and the female head is used for driving the sub heads to rotate, so that all the wafers to be ground are ground on the same grinding platform simultaneously. The utility model can grind at least two wafers on the same grinding platform at the same time, thereby improving the efficiency of the chemical mechanical grinding equipment.

Description

Chemical mechanical polishing equipment

Technical Field

The utility model relates to the technical field of semiconductors, in particular to chemical mechanical polishing equipment.

Background

In the semiconductor wafer manufacturing process, with the reduction of feature size and the increase of metal interconnection in the integrated circuit manufacturing process, the requirement for the flatness of the wafer surface is higher and higher, therefore, Chemical Mechanical Polishing (CMP) is required, the CMP is implemented by a chemical mechanical polishing apparatus, which mainly comprises a polishing Platform (Platform), a polishing Pad (Pad), a polishing Head (Head), a polishing Slurry (Slurry) supply device and a Diamond Conditioner (Diamond Conditioner), and the wafer surface is removed by the friction between the polishing Platform and the wafer and the synergistic action of the chemical reaction between the polishing Slurry and the wafer surface, and the planarization is achieved by three stages of rough grinding, fine grinding and fine grinding. The existing grinding head structure has four grinding heads per machine, each set of grinding head can clamp one wafer, the grinding head circularly passes through the steps of Up Load > rough grinding > > fine grinding > Down Load, and all the steps are carried out simultaneously in order to improve the production efficiency. However, with the annual increase of the yield, the CMP step of each machine can be performed only one by one, which obviously does not meet the requirement, and in order to further improve the yield and efficiency, only a plurality of machines can be purchased, but the price of the machine is high, and the cost is too high for improving the operation efficiency by simply increasing the number of machines, so that it has a great significance for how to improve the efficiency of the machine.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide chemical mechanical polishing equipment, which can simultaneously polish at least two wafers on the same polishing platform, thereby improving the efficiency of the chemical mechanical polishing equipment.

In order to achieve the above object, the present invention provides a chemical mechanical polishing apparatus, comprising:

the conveying device is used for receiving the wafer to be ground and unloading the ground wafer;

the plurality of grinding platforms are respectively used for grinding the wafer to be ground;

the mounting frame rotates to drive the grinding head to the grinding platform to grind the wafer to be ground, and after the grinding head finishes grinding, the mounting frame rotates to drive the grinding head to the conveying device to unload the ground wafer;

the grinding head comprises a female head and at least two sub heads, the female head is connected with all the sub heads through gears, all the sub heads are used for sucking a wafer to be ground from the conveying device at the same time, and the female head is used for driving the sub heads to rotate, so that all the wafers to be ground are ground on the same grinding platform at the same time.

Optionally, in the chemical mechanical polishing apparatus, the number of the polishing platforms is three, and the three polishing platforms are respectively: rough grinding platform, fine grinding platform and accurate grinding platform.

Optionally, in the chemical mechanical polishing apparatus, the mounting rack is in a sheet shape, the first rotation shaft is arranged in the middle of the mounting rack, the edge of the mounting rack has four blades, and each blade has a polishing head thereon.

Optionally, in the chemical mechanical polishing apparatus, a second rotating shaft is further provided in the middle of the female head.

Optionally, in the chemical mechanical polishing apparatus, the second rotating shaft has a hollow structure.

Optionally, in the chemical mechanical polishing apparatus, a polishing liquid supply pipe is further disposed in the middle of the second rotating shaft, and the polishing liquid supply pipe is configured to supply polishing liquid to the polishing platen.

Optionally, in the chemical mechanical polishing apparatus, the sub-head includes a gear and a chuck fixedly connected to the gear, the chuck is configured to suck the wafer to be polished, the main head includes a gear, and the gear of the main head and the gear of the sub-head are connected in a manner of being clamped to each other.

Optionally, in the chemical mechanical polishing apparatus, on the same polishing head, a ratio of the number of the sub heads to the number of the main heads is 2 to 4.

Optionally, in the chemical mechanical polishing apparatus, each polishing head has three sub heads, the female head is located in the middle, and the three sub heads are respectively located around the female head.

Optionally, in the chemical mechanical polishing apparatus, the three sub heads are uniformly arranged around the female head.

In the chemical mechanical polishing equipment provided by the utility model, one polishing head comprises at least two sub heads and one mother head, and the mother head simultaneously controls the actions of the two sub heads, and each sub head can clamp one wafer for polishing, so that at least two wafers can be simultaneously polished on the same polishing platform in the same time period, and the efficiency of the chemical mechanical polishing equipment is improved.

Drawings

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

FIG. 2 is a schematic view of a polishing head according to an embodiment of the present invention;

FIG. 3 is a longitudinal cross-sectional view of the polishing head of an embodiment of the present invention;

FIG. 4 is a schematic view of a polishing head sucking a wafer according to an embodiment of the present invention;

in the figure: 100-conveying device, 200-grinding platform, 210-rough grinding platform, 220-fine grinding platform, 230-fine grinding platform, 300-grinding head, 310-female head, 320-male head, 321-gear, 322-suction disc, 331-grinding fluid supply pipe, 400-mounting frame, 510-first rotating shaft, 520-second rotating shaft and 600-wafer.

Detailed Description

The following describes in more detail embodiments of the present invention with reference to the schematic drawings. The advantages and features of the present invention will become more apparent from the following description. It is to be noted that the drawings are in a very simplified form and are not to precise scale, which is provided for the purpose of facilitating and distinctly claiming the embodiments of the present invention.

In the following, the terms "first," "second," and the like are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances. Similarly, if the method described herein comprises a series of steps, the order in which these steps are presented herein is not necessarily the only order in which these steps may be performed, and some of the described steps may be omitted and/or some other steps not described herein may be added to the method.

The inventor finds that the grinding head is not separated in the whole chemical mechanical grinding step, but each grinding head can only bear a single wafer at present, although the coarse grinding, the fine grinding and the fine grinding are all carried out at the same time, the number of wafers which can be processed in unit time is limited, and along with the large-scale production expansion of a factory, the production efficiency of a single machine is also an important factor for improving the production efficiency of the whole factory, so if a proper method can be adopted, some structures of the machine are improved, and the significance for improving the production efficiency of the single machine in unit time is great.

Therefore, referring to fig. 1 to 4, the present invention provides a chemical mechanical polishing apparatus, comprising:

a transfer device 100 for receiving a wafer to be polished and unloading the polished wafer;

a polishing platform 200 for polishing the wafer to be polished;

a polishing head 300 mounted on the mounting frame 400, wherein after the polishing head 300 obtains the wafer to be polished from the transmission device 100, the mounting frame 400 rotates to drive the polishing head 300 to the polishing platform 200 to polish the wafer to be polished, and after polishing is completed, the mounting frame 400 rotates to drive the polishing head 300 to the transmission device 100 to unload the polished wafer;

the polishing head 300 includes a female head 310 and at least two sub heads 320, the female head 310 and all the sub heads 320 are connected by a gear, all the sub heads 320 are used for simultaneously sucking a wafer to be polished from the transfer device 100, and the female head 310 is used for driving the sub heads 320 to rotate, so that all the wafers to be polished are simultaneously polished on the polishing platform 200.

In the embodiment of the present invention, there are three polishing platforms 200, which are respectively: rough grinding table 210, fine grinding table 220, and finish grinding table 230; the rough grinding platform 210 performs a first grinding on the wafer; the fine grinding platform 220 performs a second grinding on the wafer; the lapping table 230 performs a third grinding operation on the wafer. The three polishing platforms 200 may or may not simultaneously polish the wafers, preferably, the wafers are simultaneously polished, thereby improving efficiency. In the embodiment of the utility model, each wafer needs to be ground for three times, namely coarse grinding, fine grinding and fine grinding, and the fineness degrees of the three times of grinding are different as the name suggests.

Preferably, the mounting frame 400 is a plate, the middle of the mounting frame 400 has a first rotating shaft 510, the mounting frame 400 rotates through the first rotating shaft 510, the edge of the mounting frame 400 has four blades, each blade has a polishing head 300 thereon, the polishing head 300 revolves around the first rotating shaft 510, the polishing head 300 rotates counterclockwise around the first rotating shaft 510, the three polishing heads 300 are in one-to-one correspondence with the three polishing platforms 200 and polish wafers to be polished, and one polishing head 300 corresponds to the transfer device 100 and receives wafers to be polished and unloads the polished wafers. When three polishing heads 300 perform polishing, one polishing head 300 and the mounting frame 400 rotate, four polishing heads 300 all rotate, and after each rotation, the three polishing heads 300 still correspond to the three polishing platforms 200 one by one, and in order to increase efficiency, one polishing head 300 is added to perform wafer picking and placing in the conveying device 100 when other polishing heads 300 perform polishing, so that four blades are formed, that is, four polishing heads 300 are mounted, and one polishing head 300 corresponds to the conveying device 100. After stabilization, at any time, there are three polishing heads 300 corresponding to the three polishing platforms 200, and different polishing is performed on different polishing platforms 200, and another polishing head 300 sucks or places a wafer on the transfer device 100. For example, the four polishing heads 300 are a first polishing head 300, a second polishing head 300, a third polishing head 300 and a fourth polishing head 300, respectively, after the first polishing head 300 sucks the wafer on the transfer device 100, the first polishing head 300 transfers to the rough polishing platform 210 for rough polishing, and the second polishing head 300 sucks the wafer on the transfer device 100; then, the first polishing head 300 transfers to the fine polishing platform 220 for fine polishing, the second polishing head 300 transfers to the rough polishing platform 210 for rough polishing, and the third polishing head 300 sucks the wafer on the transferring device 100; then, the wafers of the first polishing head 300 are polished completely, and transferred to the transfer device 100 to be placed on the wafers, the robot moves the polished wafers on the transfer device 100 to the wafer box, the robot moves three wafers to be polished from another wafer box to the transfer device 100, and the fourth polishing head 300 sucks the non-polished wafers from the transfer device 100; thereafter, the second polishing head 300 is transferred to the fine grinding platform 230 for fine grinding, the third polishing head 300 is transferred to the fine grinding platform 220 for fine grinding, and the fourth polishing head 300 is transferred to the rough grinding platform 210 for rough grinding. In turn, each subsequent rotation will be followed by a rough grind, a finish grind and a finish grind, and these three may or may not be performed simultaneously, but each time three are required to be completed and then rotated. In the embodiment of the present invention, each polishing head 300 includes at least two sub-heads 320, which can simultaneously polish at least two wafers on each platform, thereby improving the efficiency of the chemical mechanical polishing apparatus by at least two times. If each polishing head 300 includes three sub-heads 320, the efficiency of the chemical mechanical polishing apparatus can be increased by three times.

Preferably, four polishing heads 300 are uniformly arranged on the periphery of the first rotating shaft 510, the included angle between the centers of adjacent polishing heads 300 and the line of the first rotating shaft 510 is 90 °, and the included angle between the axes of adjacent polishing heads 300 and the line of the first rotating shaft 510 is 90 °. The four polishing heads 300 are disposed around the first rotation axis 510, and the four blades are disposed around the first rotation axis 510.

Further, referring to fig. 3 in detail, fig. 3 is a longitudinal sectional view of the female head, the female head 310 further has a second rotating shaft 520 in the middle, the female head 310 rotates around the second rotating shaft 520, the second rotating shaft 520 is hollow, the middle is further provided with a polishing slurry supply pipe 331 for supplying the polishing slurry onto the polishing platen 200. While the sub head 320 performs physical polishing on the stage, a polishing liquid is supplied to perform chemical polishing, and simultaneously, the mother head 310 supplies the polishing liquid to the sub head 320. The polishing liquid supply pipe 331 is one pipe, and after being transferred to the corresponding polishing platen 200, the polishing liquid is sprayed onto the polishing platen 200, and the wafer is physically rubbed against the polishing platen 200, and the polishing liquid reacts with the surface of the wafer and is chemically polished.

In an embodiment of the present invention, referring to fig. 4 in detail, fig. 4 is a longitudinal sectional view of a sub-head, the sub-head 320 includes a gear 321 and a chuck 322 fixedly connected to the gear 321, and the chuck 322 sucks a wafer 600 to be polished. The female head 310 comprises a gear, the gear of the female head 310 is clamped with the gear of the male head 320, and when the female head 310 rotates, the gear of the male head 320 is driven to rotate, and the sucker 322 is driven to rotate. The center of the gear of the sub-head 320 may be hollow or solid. The rotation speed and pressure of the three sub heads 320 are controlled by the female head 310.

Preferably, the ratio of the number of the sub heads 320 to the number of the female heads 310 in the same polishing head 300 is 2 to 4. For example, in the present invention, each polishing head 300 has three sub heads 320, the female head 310 is located in the middle, the three sub heads 320 are respectively located around the female head 310, and the three sub heads 320 are uniformly arranged around the female head 310, and an included angle between a connecting line of centers of adjacent sub heads 320 and a center of the female head 310 is 120 °, which is equivalent to that the three sub heads 320 are uniformly arranged around the female head 310.

In summary, in the chemical mechanical polishing apparatus provided in the embodiments of the present invention, one polishing head includes at least two sub heads and one mother head, and the mother head simultaneously controls the actions of the two sub heads, so that each sub head can clamp one wafer for polishing, and therefore, in the same time period, at least two wafers can be simultaneously polished on the same polishing platform, thereby improving the efficiency of the chemical mechanical polishing apparatus.

The above description is only a preferred embodiment of the present invention, and does not limit the present invention in any way. It will be understood by those skilled in the art that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the utility model as defined by the appended claims.

Claims

1. A chemical mechanical polishing apparatus, comprising:

the grinding head is arranged on a mounting rack, and the mounting rack is used for driving the grinding head to the grinding platform and driving the grinding head to the conveying device;

2. The chemical mechanical polishing apparatus of claim 1, wherein the number of polishing platforms is three, respectively: rough grinding platform, fine grinding platform and accurate grinding platform.

3. The chemical mechanical polishing apparatus of claim 2, wherein the mounting block is plate-shaped, the mounting block having the first rotational axis in the middle thereof, the mounting block having four leaves at an edge thereof, one polishing head on each leaf.

4. The chemical mechanical polishing apparatus of claim 1, wherein the female head further has a second rotational axis in the middle.

5. The chemical mechanical polishing apparatus of claim 4, wherein the second rotating shaft is a hollow structure.

6. The chemical mechanical polishing apparatus as claimed in claim 5, wherein a polishing liquid supply pipe is further disposed in the middle of the second rotation shaft, and the polishing liquid supply pipe is configured to supply polishing liquid to the polishing platen.

7. The chemical mechanical polishing apparatus as claimed in claim 1, wherein the sub head comprises a gear, and a chuck fixedly connected to the gear, the chuck being adapted to suck the wafer to be polished, and the main head comprises a gear, and the gear of the main head and the gear of the sub head are connected by being locked to each other.

8. The chemical mechanical polishing apparatus of claim 1, wherein the ratio of the number of the sub heads to the number of the main heads on the same polishing head is 2-4.

9. The chemical mechanical polishing apparatus of claim 8, wherein each of said polishing heads has three sub-heads, said female head being located at the center, and three of said sub-heads being located at the periphery of said female head, respectively.

10. The chemical mechanical polishing apparatus of claim 1, wherein three of the sub heads are uniformly disposed around the female head.