CN220065625U - Comprehensive cleaning equipment for chemically mechanical polished wafer - Google Patents

Abstract

The embodiment of the utility model discloses comprehensive cleaning equipment for chemically mechanical polished wafers, wherein a cleaning cavity is arranged between a lower disc of a wafer taking machine and a wafer collecting box, a lower wafer assembly for conveying the wafers into the cleaning cavity is arranged on the lower disc, and a roller assembly for conveying the wafers from the lower wafer end to the wafer collecting end of the cleaning cavity, a spray head for spraying cleaning liquid and a brush head for brushing the wafers are arranged in the cleaning cavity; the roller assembly comprises a plurality of rollers which are arranged along the width direction of the cleaning cavity, the rollers form a conveying surface along the length direction of the cleaning cavity, the brush surface of the brush head is tightly attached to the conveying surface, and the spray head is arranged towards the conveying surface. The problems of complex equipment operation and poor wafer cleaning effect in the prior art are effectively solved.

Description

Comprehensive cleaning equipment for chemically mechanical polished wafer

Technical Field

The utility model relates to the technical field of semiconductor processing, in particular to comprehensive cleaning equipment for wafers after chemical mechanical polishing.

Background

In the semiconductor industry, chemical mechanical polishing (Chemical Mechanical Polishing, CMP) is a means of achieving global planarization in integrated circuit fabrication, and is widely used to planarize material layers on wafers. Firstly, the surface material of the workpiece is subjected to chemical reaction with an oxidant, a catalyst and the like in the polishing solution to generate a soft layer which is relatively easy to remove, then the soft layer is removed under the mechanical action of an abrasive in the polishing solution and a polishing pad, so that the surface of the workpiece is exposed again, and then the chemical reaction is carried out, so that the surface polishing of the workpiece is completed in the alternate process of the chemical action process and the mechanical action process.

After the chemical mechanical polishing process, the wafer is transferred to a cleaning unit, and the water column subjected to ultrasonic vibration is sprayed to the surface of the wafer during cleaning to clean the residual particles on the surface of the wafer. Still other solutions would be to add a brushing unit after the cleaning unit and then brush.

However, this cleaning method does not provide a good cleaning effect on the wafer. On one hand, two working procedures of cleaning and brushing are needed after the completion of the lower wafer, and the wafer circulation time is long. After polishing, the surface of the wafer has obvious polishing liquid residues, and the polishing liquid is attached to the surface of the wafer because the time required for flowing to the cleaning unit is long, so that the operation of a cleaning brush piece in the next step is not easy to remove, and the polishing passing rate is reduced. On the other hand, the water column can only remove the particles with larger surfaces/polishing solution, small particles on the surface of the wafer cannot be removed in time, and when the small particles are combined with the surface of the wafer through chemical bonds, the subsequent working procedures are difficult to remove, and the reworking treatment is required to cause waste of productivity.

In addition, 3 pieces of equipment for discharging, cleaning and brushing the sheets are required to be operated, the steps are complex, the equipment occupies large space, the equipment is more, the personnel are more, the material requirement is high, and the total cost is high.

In the wafer processing process in the prior art, the adopted cleaning, brushing and discharging equipment is complex in operation, more in equipment, large in occupied space and more in operators, and the problem of wafer surface polishing liquid and small particle residues caused by the wafer flow process after polishing is finished.

Disclosure of Invention

The embodiment of the utility model provides comprehensive cleaning equipment for wafers after chemical mechanical polishing, which effectively solves the problems of complex equipment operation and poor wafer cleaning effect in the prior art.

The utility model provides comprehensive cleaning equipment for wafers after chemical mechanical polishing, which is characterized in that a cleaning cavity is arranged between a lower disc of a wafer taking machine and a wafer collecting box, a lower wafer assembly for conveying the wafers into the cleaning cavity is arranged on the lower disc, and a roller assembly for conveying the wafers from the lower wafer end to the wafer collecting end of the cleaning cavity, a spray head for spraying cleaning liquid and a brush head for brushing the wafers are arranged in the cleaning cavity;

the roller assembly comprises a plurality of rollers which are arranged along the width direction of the cleaning cavity, the rollers form a conveying surface along the length direction of the cleaning cavity, the brush surface of the brush head is tightly attached to the conveying surface, and the spray head is arranged towards the conveying surface.

Further, the roller assembly comprises an upper roller and a lower roller, wherein the upper roller and the lower roller are staggered along the length direction of the conveying surface.

Further, the brush head comprises an upper brush head and a lower brush head, wherein the upper brush head is arranged between two adjacent upper rollers, and the lower brush head is arranged between two adjacent lower rollers.

Further, the lower piece tray is rotatably fixed on the piece taking machine through a rotating shaft, and the lower piece assembly is a water gun which is arranged above the lower piece tray and faces to the lower piece end of the cleaning cavity.

Further, the lower sheet end is provided with the upper roller and the lower roller relatively, and the sheet collecting end is provided with the upper roller and the lower roller relatively.

Further, the spray heads comprise a plurality of first spray heads for spraying liquid medicine and a plurality of second spray heads for spraying clean water;

and/or the first spray head is arranged on the front half section of the cleaning cavity close to the lower sheet end, and the second spray head is arranged on the rear half section of the cleaning cavity close to the sheet collecting end.

Further, a connecting rod capable of reciprocating movement is arranged in the cleaning cavity along the width direction, and the brush head is arranged on the connecting rod.

Further, a plurality of self-rotating motors are arranged on the connecting rod, and the brush head is connected to the connecting rod through the self-rotating motors.

Further, the lower disc is obliquely arranged with the disc collecting box, the lower point of the edge of the lower disc is connected with the lower disc end of the conveying surface, and the high point of the disc collecting box is connected with the disc collecting end of the conveying surface.

Further, the lower sheet box is arranged on a lifting table and comprises a plurality of vertically arranged sheet grooves, and the lifting table is used for driving the lower sheet box to enable the sheet grooves to be connected with the lower sheet ends of the conveying surfaces.

The utility model sets a cleaning cavity between the lower disc and the collecting box, and sets a roller component, a brush head and a spray head in the cleaning cavity, so that the wafer is transmitted through the roller component in the process of leaving the lower disc and reaching the collecting box, and is directly brushed by the brush head in the transmission process, and is cleaned by the spray head. On one hand, the technical scheme of the utility model combines the three working procedures of sheet feeding (actually referred to as a transportation process), sheet brushing and sheet cleaning, and compared with the prior art that the two working procedures of sheet feeding, sheet brushing and sheet cleaning are carried out after the completion of sheet feeding, the technical scheme shortens the time required by wafer circulation, improves the working efficiency, simultaneously ensures the first environment after the completion of wafer polishing, reduces the possibility of combining polishing liquid with the surface of the wafer, and improves the cleanliness of the surface of the wafer. On the other hand, the scheme is improved on the basis of the sheet taking machine, and three steps of sheet discharging, sheet brushing and cleaning can be integrated on one device, so that the space occupied by the device can be reduced, the operation steps are simplified, and the cost of operators is reduced.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the drawings that are needed in the description of the embodiments will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present utility model, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic side view of an integrated cleaning apparatus for chemically mechanically polished wafers according to an embodiment of the present utility model;

FIG. 2 is a schematic view of a drum assembly and brush head of an integrated cleaning apparatus for chemically mechanically polished wafers according to an embodiment of the present utility model;

fig. 3 is a schematic structural diagram of a connection between a lower plate and a cleaning chamber of an integrated cleaning apparatus for chemically mechanically polished wafers according to an embodiment of the present utility model.

The reference numerals are as follows:

10. a lower sheet assembly; 11. a lower plate; 12. a water gun; 13. a circular groove; 14. a rotating shaft; 30. cleaning the cavity; 31. a roller assembly; 311. a roller; 312. a drum shaft; 32. a brush head; 321. a connecting rod; 322. a self-rotation motor; 33. a spray head; 331. a first nozzle; 332. a second nozzle; 34. a conveying surface; 35. a housing; 36. a lower sheet end; 37. a receiving end; 40. a receiving box; 41. a sheet groove; 42. a water tank.

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present utility model, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to fall within the scope of the utility model.

In the description of the present utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on the drawings are merely for convenience in describing the present utility model and simplifying the description, and do not indicate or imply that the apparatus or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more features. In the description of the present utility model, the meaning of "a plurality" is two or more, unless explicitly defined otherwise.

In the present utility model, the word "in a preferred embodiment" is used to mean "serving as an example, instance, or illustration. Any embodiment described herein as "in a preferred embodiment" is not necessarily to be construed as preferred or advantageous over other embodiments. The following description is presented to enable any person skilled in the art to make and use the utility model. In the following description, details are set forth for purposes of explanation. It will be apparent to one of ordinary skill in the art that the present utility model may be practiced without these specific details. In other instances, well-known structures and processes have not been described in detail so as not to obscure the description of the utility model with unnecessary detail. Thus, the present utility model is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein.

After the cmp process, the wafer is transferred to a cleaning apparatus, commonly referred to as a wafer carrier, typically performed by a wafer extractor in the prior art. During cleaning, the water column subjected to ultrasonic vibration is sprayed onto the surface of the wafer to clean the remaining particles on the surface of the wafer, which is generally called cleaning. In still other embodiments, a brushing device may be added after the cleaning device, and the wafer surface may be brushed with a brush head, which is referred to as a brush sheet.

Referring to fig. 1 to 3, an embodiment of the present utility model provides an integrated cleaning apparatus for chemically mechanically polished wafers, a cleaning chamber 30 is provided between a lower tray 11 of a wafer taking machine and a wafer receiving box 40, a lower wafer assembly 10 for transporting the wafers into the cleaning chamber 30 is provided on the lower tray 11, a drum assembly 31 for transporting the wafers from a lower end 36 to a wafer receiving end 37 of the cleaning chamber 30, a spray head 33 for spraying cleaning liquid, and a brush head 32 for brushing the wafers are provided in the cleaning chamber 30; the roller assembly 31 includes a plurality of rollers 311 arranged in the width direction of the cleaning chamber 30, the plurality of rollers 311 forming a conveying surface 34 in the length direction of the cleaning chamber 30, the brush surface of the brush head 32 being disposed against the conveying surface 34, and the shower head 33 being disposed toward the conveying surface 34.

It should be noted that the conveying surface 34 is a virtual surface and is not a structure that actually exists, and is labeled in fig. 1 for ease of understanding and description.

The lower platen 11 is a polishing platen of a chemical mechanical polishing apparatus, and a ceramic platen is generally used. The cassette 40 refers to a cassette for receiving wafers, also referred to as a wafer cassette. As can be seen in conjunction with fig. 1, the lower end 36 of the wash chamber 30 is near the end of the lower tray 11, and the receiving end 37 of the wash chamber 30 is near the end of the receiving box 40.

The utility model sets a cleaning cavity 30 between the lower disc 11 and the collecting box 40 of the tablet machine, and sets a roller component 31, a brush head 32 and a spray head 33 in the cleaning cavity 30, so that the wafers are transmitted through the roller component 31 in the process of leaving the lower disc 11 and reaching the collecting box 40, and are directly scrubbed by the brush head 32 in the transmission process, and are cleaned by the spray head 33. On one hand, the technical scheme of the utility model combines the three working procedures of sheet feeding (actually referred to as a transportation process), sheet brushing and sheet cleaning, and compared with the prior art that the two working procedures of sheet feeding, sheet brushing and sheet cleaning are carried out after the completion of sheet feeding, the technical scheme shortens the time required by wafer circulation, improves the working efficiency, simultaneously ensures the first environment after the completion of wafer polishing, reduces the possibility of combining polishing liquid with the surface of the wafer, and improves the cleanliness of the surface of the wafer. On the other hand, the scheme is improved on the basis of the sheet taking machine, and three steps of sheet discharging, sheet brushing and cleaning can be integrated on one device, so that the space occupied by the device can be reduced, the operation steps are simplified, and the cost of operators is reduced.

In a preferred embodiment, the lower sheet end 36 is provided with an upper roller and a lower roller opposite each other, and the take-up end 37 is provided with an upper roller and a lower roller opposite each other.

The upper and lower rollers rotate about an axis to collectively drive the wafer from the lower end 36 of the cleaning chamber 30 toward the take-up end 37. It will be appreciated that the rotational directions of the upper and lower drums are opposite, as shown in fig. 1, with the upper drum rotating counterclockwise and the lower drum rotating clockwise.

The upper roller and the lower roller are respectively arranged at the upper side and the lower side of the conveying surface 34, after the wafer enters the lower roller 36 of the cleaning cavity 30 from the lower disc 11, the wafer firstly moves towards the receiving end 37 under the clamping and rotating drive of the first upper roller and the first lower roller which are oppositely arranged, and the wafer reaches the receiving end 37 of the cleaning cavity 30 and comes out from the last upper roller and the last lower roller which are oppositely arranged and enters the receiving box 40.

The first upper roller and the first lower roller are oppositely arranged, so that the wafer is clamped to enter the cleaning cavity 30, the positioning and direction adjusting effects can be achieved, and the wafer is ensured to enter the conveying surface 34 in the cleaning cavity 30, and the direction and the position of the conveying surface 34 are consistent. And the two rollers 311 convey the wafer together, so that the pushing force on the wafer is greater. When the wafer leaves the cleaning chamber 30, the last upper roller and the last lower roller are arranged oppositely, so that the functions of positioning and direction adjustment can be achieved, and the wafer is ensured to enter the wafer collecting box 40.

The roller assembly 31 is a common transmission structure, and the transmission structure of the roller assembly 31 is not particularly limited in the present embodiment, and those skilled in the art will understand that there are many possible embodiments of the transmission structure of the roller assembly 31, such as:

the outer surface of the cleaning cavity 30 is provided with a shell 35, two sides of the shell 35 in the width direction are provided with brackets, bearings are arranged in the brackets, a roller shaft 312 of the roller assembly 31 is arranged in the bearings, two sides of the roller shaft 312 are provided with gears, the gears are matched with chains, and the chains are connected with a motor and used for driving the roller 311 to rotate.

In a preferred embodiment, the roller assembly 31 includes upper and lower rollers that are staggered along the length of the conveying surface 34. The brush head 32 includes an upper brush head 32 and a lower brush head 32, the upper brush head 32 being disposed between two adjacent upper rollers and the lower brush head 32 being disposed between two adjacent lower rollers.

The upper rollers and the lower rollers are arranged in a staggered manner, the brush head 32 is arranged between the two adjacent rollers 311, the brush head 32 is used for brushing the surface of the wafer while the rollers 311 drive the wafer, and the upper brush head 32 and the lower brush head 32 are arranged in a staggered manner, so that the upper surface and the lower surface of the wafer can be brushed, and the liquid medicine and particles for cleaning the surface of the wafer can be cleaned.

In a preferred embodiment, lower tray 11 is rotatably mounted to the extractor by shaft 14, and lower tray assembly 10 is a water gun 12 disposed above lower tray 11 and facing lower end 36 of wash chamber 30.

The lower tray 11 is provided with a plurality of circular grooves 13 for placing wafers, and the water gun 12 flushes water towards the lower end 36 of the cleaning cavity 30 to flush out the wafers in the circular grooves 13 and enter the cleaning cavity 30. The lower disc 11 rotates through the rotating shaft 14, and in the rotating process, different circular grooves 13 sequentially turn to the positions facing the muzzle of the water gun 12, so that a plurality of wafers in the lower disc 11 sequentially flush into the cleaning cavity 30, and the working efficiency is improved.

In a preferred embodiment, the spray head 33 includes a plurality of first spray heads 331 for spraying a chemical solution, and a plurality of second spray heads 332 for spraying clear water;

and/or, the first spray head 331 is disposed on a front half section of the cleaning chamber 30 near the lower sheet end 36, and the second spray head 332 is disposed on a rear half section of the cleaning chamber 30 near the collecting end 37.

The first spray head 331 is used for spraying liquid medicine, and the liquid medicine can react with the polishing solution on the surface of the wafer to the cleaning polishing solution, the first spray head 331 is connected with a liquid medicine supply system, and a specific structure of the liquid medicine supply system can be obtained from the existing scheme by a person skilled in the art, and the scheme is not repeated. At the same time, the brush head 32 contacts the wafer surface, and impurities on the wafer surface perform brush cleaning work.

The second spray head 332 is used for spraying clean water, so that the residual liquid medicine and polishing liquid on the surface of the wafer are washed clean. At the same time, the brush head 32 contacts the wafer surface to clean the residual liquid medicine and particles on the wafer surface.

The first shower nozzle 331 is arranged on the first half section, the second shower nozzle 332 is arranged on the second half section, the polishing solution is firstly neutralized, the polishing solution is prevented from adhering to the surface of the wafer, and then the residual liquid medicine and larger particles on the surface of the wafer are washed cleanly by clean water.

In a preferred embodiment, a reciprocating link 321 is provided in the cleaning chamber 30 in the width direction, and the brush head 32 is provided on the link 321.

The driving link 321 reciprocates along the width direction of the cleaning chamber 30, and a crank link 321 mechanism may be adopted, and crank rotation drives the link 321 to reciprocate, which is a conventional mechanical structure in the art, and will not be described here.

Of course, other structures may be used to drive the connecting rod 321 to reciprocate, and the present solution is not limited in particular.

The connecting rod 321 reciprocates to drive the brush head 32 to reciprocate, thereby playing a role in brushing the surface of the wafer.

In a preferred embodiment, the connecting rod 321 is provided with a plurality of rotation motors 322, and the brush head 32 is connected to the connecting rod 321 through the rotation motors 322.

The brush head 32 is connected to the connecting rod 321 through a small-sized rotation motor 322, and the brush head 32 rotates while reciprocating along the width direction, so that the cleaning work of brushing the impurities on the surface of the wafer is better performed.

It will be appreciated that the spray head 33, brush head 32 and roller assembly 31 used in this embodiment are all made of acid and alkali resistant materials.

In a preferred embodiment, lower tray 11 is inclined with respect to cassette 40, with the lower edge of lower tray 11 being in contact with lower end 36 of transport surface 34 and the upper edge of cassette 40 being in contact with receiving end 37 of transport surface 34.

Referring to fig. 1, in a specific embodiment, the lower tray 11 is obliquely disposed, and the lower point of the lower tray 11 is connected to the lower end 36 of the cleaning chamber 30, and the inclination angle of the lower tray 11 is consistent with the inclination angles of the cleaning chamber 30, the conveying surface 34, and the wafer receiving box 40, so that the wafer conveying direction is consistent, and the wafer circulation among the lower tray 11, the cleaning chamber 30, and the wafer receiving box 40 is easier.

In a preferred embodiment, the lower cassette is mounted on a lift table and includes a plurality of vertically disposed tab slots 41, the lift table being adapted to drive the lower cassette such that the tab slots 41 interface with the lower tab ends 36 of the transport surface 34.

Referring to fig. 1, in one embodiment, after a wafer enters a first wafer slot 41, the lift table is raised or lowered and the wafer can enter a second wafer slot 41. It will be appreciated that the height of each lift of the lift table is predetermined based on the spacing of the sheet grooves 41 such that after each lift, the sheet grooves 41 are in close contact with the lower sheet ends 36 of the transport surface 34.

In one particular embodiment, the pod 40 may be placed in a water tank 42 so that the cleaned wafers are collected and immersed in water for the next operation.

The foregoing has outlined some of the more detailed description of an integrated cleaning apparatus for chemical mechanical polished wafers in accordance with the embodiments of the present utility model, wherein the detailed description is provided for the purpose of illustrating the principles and embodiments of the present utility model and for the purpose of facilitating an understanding of the method and core concepts thereof; meanwhile, the contents of the present specification should not be construed as limiting the present utility model in view of the fact that those skilled in the art can vary in specific embodiments and application scope according to the ideas of the present utility model.

Claims (10)

1. The comprehensive cleaning equipment for the wafer after the chemical mechanical polishing is characterized in that a cleaning cavity is arranged between a lower disc of a wafer taking machine and a wafer collecting box, a lower wafer assembly for conveying the wafer into the cleaning cavity is arranged on the lower disc, and a roller assembly for conveying the wafer from the lower wafer end to the wafer collecting end of the cleaning cavity, a spray head for spraying cleaning liquid and a brush head for brushing the wafer are arranged in the cleaning cavity;

the roller assembly comprises a plurality of rollers which are arranged along the width direction of the cleaning cavity, the rollers form a conveying surface along the length direction of the cleaning cavity, the brush surface of the brush head is tightly attached to the conveying surface, and the spray head is arranged towards the conveying surface.

2. The integrated cleaning apparatus for post-cmp wafers of claim 1 wherein the roller assembly comprises an upper roller and a lower roller, the upper roller and the lower roller being staggered in a direction along the length of the transport surface.

3. The integrated cleaning apparatus for post-cmp wafers of claim 2 wherein the brush head comprises an upper brush head disposed between two adjacent upper rollers and a lower brush head disposed between two adjacent lower rollers.

4. The integrated cleaning apparatus for post-cmp wafers of claim 3 wherein the lower plate is rotatably secured to the extractor by a spindle, and the lower plate assembly is a water gun disposed above the lower plate and directed toward a lower plate end of the cleaning chamber.

5. The integrated cleaning apparatus for post-cmp wafers of claim 4 wherein the lower platen end is opposite the upper platen and the lower platen, and the take-up platen end is opposite the upper platen and the lower platen.

6. The integrated cleaning apparatus for post-cmp wafers of claim 1 wherein the spray heads comprise a plurality of first spray heads for spraying a chemical solution and a plurality of second spray heads for spraying clean water;

and/or the first spray head is arranged on the front half section of the cleaning cavity close to the lower sheet end, and the second spray head is arranged on the rear half section of the cleaning cavity close to the sheet collecting end.

7. The integrated cleaning apparatus for post-cmp wafers of claim 6 wherein the cleaning chamber is provided with a connecting rod reciprocating in a width direction, and the brush head is disposed on the connecting rod.

8. The integrated cleaning apparatus for post-cmp wafers of claim 7 wherein the link is provided with a plurality of spin motors, the brush head being coupled to the link by the spin motors.

9. The integrated cleaning apparatus for post-cmp wafers of claim 1 wherein the lower tray is disposed obliquely to the cassette, the lower tray edge low point is connected to the lower end of the transport surface, and the upper tray high point is connected to the receiving end of the transport surface.

10. The integrated cleaning apparatus for post-cmp wafers of claim 2 wherein the lower platen is disposed on a lift table and includes a plurality of vertically disposed platen slots, the lift table being configured to drive the lower platen such that the platen slots are in engagement with lower platen ends of the transport surface.