JP6031426B2 - Polishing apparatus and polishing method - Google Patents

Description

The present invention relates to a polishing apparatus and a polishing method, and in particular, the surface of an object to be polished is prevented from being generated on the surface of an object to be polished (substrate) such as a wafer by the scattered and dried polishing liquid. The present invention relates to a polishing apparatus and a polishing method for polishing and flattening.
The present invention also relates to a polishing apparatus, and in particular, polishes the surface of an object to be polished (substrate) such as a wafer while preventing various covers disposed around the polishing table from being contaminated by the polishing liquid. And a polishing apparatus for flattening.

  A polishing apparatus for polishing the surface of a wafer generally includes a polishing table for supporting a polishing pad having a polishing surface and a top ring (polishing head) for holding the wafer. Then, while pressing the wafer held by the top ring with a predetermined pressure against the polishing surface of the polishing pad, the polishing table and the top ring are moved relative to each other to bring the wafer into sliding contact with the polishing surface. Polish the surface to a flat and mirror surface. In chemical mechanical polishing (CMP), a polishing liquid (slurry) is supplied onto the polishing pad during polishing.

  Thus, when the surface of a substrate such as a wafer is polished while supplying the polishing liquid, the polishing liquid is scattered around the polishing table. After polishing, the polishing surface is cleaned by spraying a liquid mixture (for example, pure water) of a liquid (for example, pure water) and a gas (for example, nitrogen gas) or a liquid (for example, pure water) from the atomizer onto the polishing surface of the polishing pad. Even when the polishing surface is cleaned by the atomizer, the polishing liquid remaining on the polishing surface is scattered around the polishing table. Then, when the scattered polishing liquid adheres to various components arranged around the polishing table and the inner wall surface of the chamber containing the polishing apparatus and is dried, the dried polishing liquid is peeled off and polished. It falls on the table and causes scratches on the substrate.

  In general, various cleaning nozzles are disposed at predetermined positions of the polishing apparatus, and the cleaning liquid is periodically sprayed from the cleaning nozzles toward predetermined portions of the polishing apparatus to be disposed around the polishing table and its periphery. Wash away the polishing liquid adhering to the surface of the components to be washed with the cleaning liquid. However, even if the polishing liquid is washed away with the cleaning liquid, the polishing liquid may adhere to the surface of components or the like disposed around the polishing table and may dry. As described above, when the polishing liquid adheres to the surface of the component or the like and is dried, it becomes difficult to wash the dried polishing liquid with the cleaning liquid. When the dry polishing liquid repeatedly accumulates, it eventually peels off and falls onto the polishing pad, causing a scratch on the substrate.

  In order to protect the top ring head having the top ring from the scattered polishing liquid, the top ring head may be surrounded by a top ring head cover. The polishing apparatus is generally provided with a dresser for dressing the polishing surface. The dressing head having this dresser may be surrounded by a dressing head cover to be protected from the scattered cleaning liquid. Further, by surrounding the atomizing nozzle of the atomizer with an atomizer cover, the mixed fluid or polishing liquid bounced off the polishing pad may be prevented from scattering.

  The atomizer cover generally has a considerably complicated shape, and the liquid containing the polishing liquid bounced off the polishing pad tends to stay in the atomizer cover. In addition, since the atomizer cover has many corners where liquid tends to accumulate, it is generally difficult to clean the outer surface with a cleaning liquid. And if the liquid containing polishing liquid adheres and solidifies to an atomizer cover, this solidified material will fall on a grinding | polishing surface and will contaminate a grinding | polishing surface.

  In addition, it is difficult to completely prevent the scattered polishing liquid from flowing into the top ring head cover. For this reason, the polishing liquid may enter the top ring head cover and stay inside the top ring head cover, contaminating the top ring head cover or the top ring head, or dropping on the polishing surface to contaminate the polishing surface. .

JP 2008-296293 A JP 2007-168039 A JP 2003-133277 A

  The present invention can prevent the polishing liquid scattered around the polishing table during polishing of the substrate from adhering to the surfaces of various components arranged around the polishing table and drying. A first object is to provide a polishing apparatus and a polishing method capable of preventing the occurrence of scratches on the surface.

  In addition, the present invention has an atomizer cover that can prevent the liquid bounced off the polishing surface from staying on the inner surface, is relatively easy to clean with the cleaning liquid, and can prevent contamination of the polishing surface due to falling solids. A second object is to provide a polishing apparatus.

  Further, the present invention can prevent the top ring head cover or the top ring head from being contaminated by the polishing liquid even if the polishing liquid enters the inside of the top ring head cover, and the polishing liquid can be dripped onto the polishing surface. It is a third object of the present invention to provide a polishing apparatus having a top ring head cover that can prevent the polishing surface from being contaminated.

One reference example of a polishing apparatus is a rotatable polishing table for supporting a polishing pad having a polishing surface, and a movement between a polishing position above the polishing table and a substrate delivery position on the side of the polishing table. A top ring head having a top ring that freely presses the substrate against the polishing surface, a top ring head cover surrounding the top ring head, a dressing position above the polishing table, and a retreat position at a side of the polishing table. A dresser head having a dresser for dressing the polishing surface while being freely movable; a dresser head cover surrounding the dresser head; and an upper surface of the top ring and the top ring when the top ring is at the substrate delivery position. A spray nozzle for spraying a cleaning liquid on the outer surface of the head cover; There when in the retracted position, having a spray nozzle for spraying the cleaning fluid on the outer surface of the dresser head cover.

  According to this configuration, when the top ring is located at the substrate delivery position, the cleaning liquid is sprayed from the spray nozzle onto the upper surface of the top ring and the outer surface of the top ring head cover to wet the upper surface of the top ring and the outer surface of the top ring head cover. Keep in state. Further, when the dresser is in the retracted position, the cleaning liquid is sprayed from the spray nozzle onto the outer surface of the dresser head cover to keep the outer surface of the dresser head cover wet. Therefore, it is possible to prevent the polishing liquid from adhering to the upper surface of the top ring, the outer surface of the top ring head cover, and the outer surface of the dresser head cover and drying.

In preferred hurts like the reference example, the polishing apparatus further comprises an atomizer for cleaning the polished surface by spraying the cleaning fluid on the polishing surface, a spray nozzle for spraying the cleaning fluid on the outer surface of the atomizer.

  According to this configuration, for example, when the polishing surface is cleaned by spraying a cleaning fluid from the atomizer to the polishing surface or when the polishing surface is dressed with a dresser, when the substrate is not actually polished, By spraying the cleaning liquid from the spray nozzle onto the outer surface of the atomizer and keeping the outer surface of the atomizer in a wet state, it is possible to prevent the polishing liquid from adhering to the outer surface of the atomizer and drying.

In preferred hurts like the reference example, the polishing apparatus further comprises a polishing liquid supply nozzle for supplying a polishing liquid to the polishing surface, a spray nozzle for spraying a cleaning liquid to the polishing liquid supply nozzle.

  According to this configuration, for example, when the polishing surface is cleaned by spraying a cleaning fluid from the atomizer to the polishing surface or when the polishing surface is dressed with a dresser, when the substrate is not actually polished, By spraying the cleaning liquid from the spray nozzle onto the polishing liquid supply nozzle to keep the polishing liquid supply nozzle in a wet state, it is possible to prevent the polishing liquid from adhering to the outer surface of the polishing liquid supply nozzle and drying.

In preferred hurts like the reference example, the polishing apparatus further comprises a spray nozzle for spraying a cleaning liquid on the inner wall surface of the chamber housing the polishing unit therein.

  According to this configuration, for example, when the substrate is not actually polished, the cleaning liquid is sprayed onto the inner wall surface of the chamber from the spray nozzle to keep the inner wall surface of the chamber in a wet state, so that the polishing liquid is applied to the inner wall surface of the chamber. It can prevent adhering and drying.

One reference example of the polishing method is to move the top ring holding the substrate to a polishing position above the polishing table, rotate the polishing table, and polish from the polishing liquid supply nozzle to the polishing surface of the polishing pad on the polishing table. While supplying the liquid, the top ring presses the substrate against the polishing surface to polish the substrate, and the top ring holding the polished substrate is moved from the polishing position to the substrate delivery position on the side of the polishing table. The cleaning liquid is sprayed on the upper surface of the top ring and the outer surface of the top ring head cover surrounding the top ring head having the top ring.

In preferred hurts like the reference example, the polishing method, when the top ring is in said substrate delivery position, the dresser is moved to the dressing position above of the polishing table, is pressed against the dresser to the grinding surface The polishing surface is dressed, the dresser is moved from the dressing position to a retracted position on the side of the polishing table, and the cleaning liquid is sprayed on the outer surface of the dresser head cover surrounding the dresser head having the dresser.

In preferred hurts like the reference example, the polishing method, when not polishing a substrate, while washing the polished surface by spraying the cleaning fluid on the polishing surface from the atomizer, the cleaning liquid to the outer surface of the atomizer Spray.

In preferred hurts like the reference example, the polishing method, when not polishing a substrate, spraying a cleaning liquid to the polishing liquid supply nozzle.

One aspect of a polishing apparatus includes a rotatable polishing table for supporting a polishing pad having a polishing surface, an atomizer head that sprays a cleaning fluid onto the polishing surface to clean the polishing surface, and an upper surface of the atomizer head The atomizer cover, the atomizer cover has a semi-cylindrical top plate having a semi-cylindrical shape, a first side plate and a second side plate extending downward from both lower ends of the semi-cylindrical top plate, the semi-cylindrical top plate, A first top plate having an arcuate longitudinal section with a constant radius from the base end to the tip of the atomizer cover, and a first top plate having an arcuate longitudinal section with a gradually decreasing radius from the base end to the tip of the atomizer cover. The top of the first top plate and the top of the second top plate are connected to each other to form the semi-cylindrical top plate.

  According to this configuration, the atomizer cover is formed into a smooth shape with no corners that is easy to flow even if liquid is scattered on the inner surface or outer surface thereof, and the atomizer cover is prevented from being contaminated with the liquid containing the polishing liquid. be able to. Furthermore, the wiping property of the liquid containing the polishing liquid adhering to the atomizer cover can be improved. Therefore, the liquid containing the polishing liquid can be prevented from solidifying on the inner surface and the outer surface of the atomizer cover, and further, contamination of the polished surface due to the fall of the solidified product can be prevented.

In a preferred aspect, the semi-cylindrical top plate, the first side plate, and the second side plate are integrally formed of resin.
By making the atomizer cover a smooth shape with no corners, integral molding with resin becomes possible.

In a preferred aspect, lower end surfaces of the first side plate and the second side plate are inclined downward from the tip end of the atomizer cover toward the base end.
According to this configuration, the liquid flowing down on the side plate from the semi-cylindrical top plate of the atomizer cover and reaching the lower end surface of the side plate can flow on the lower end surface from the front end to the base end of the atomizer cover. it can.

In a preferred aspect, the second side plate is connected to the second top plate, and the second side plate is provided with a protruding portion that protrudes in the horizontal direction.
Thus, the atomizer cover can be reinforced with the protrusion by providing the protrusion on the second side plate. Furthermore, the splashing of the liquid can be prevented by the protrusion.

  In a preferred aspect, the polishing apparatus further includes a top ring head having a top ring that presses against the polishing surface while holding and rotating the substrate, and a top ring head cover surrounding the top ring head, the top ring head cover being A side cover that surrounds the top ring head, and a lower cover that closes a lower end opening of the side cover, and the lower cover is located when the top ring is in a polishing position above the polishing table. A bottom plate that slopes downwardly outwardly in the radial direction of the polishing table;

  According to this configuration, the polishing liquid that has entered the inside of the top ring head cover reaches the bottom plate of the lower cover, flows along the gradient of the bottom plate, and is collected on the side of the polishing table. Therefore, it is possible to prevent the top ring head cover and the top ring head from being contaminated by the polishing liquid, and the polishing liquid from being dripped onto the polishing surface and contaminating the polishing surface.

In a preferred aspect, the lower cover includes a side plate that extends upward from the outer peripheral portion of the bottom plate and contacts or is close to the side plate of the side cover.
According to this configuration, the connecting portion between the side cover and the lower cover can be positioned above the corner portion between the side cover and the lower cover, thereby polishing the corner portion between the two. It is possible to prevent the liquid from accumulating.

  According to the polishing apparatus described above, the components arranged around the polishing table such as the top ring top surface, the top ring head cover outer surface, and the dresser head cover outer surface are kept in a wet state. It is possible to prevent the polishing liquid from adhering and drying. As a result, it is possible to prevent the dried polishing liquid from falling on the polishing table and to prevent the substrate from being scratched.

  According to the above-described polishing apparatus, the atomizer cover can be prevented from being contaminated with the liquid containing the polishing liquid, and the wiping property of the liquid containing the polishing liquid attached to the atomizer cover can be improved. Therefore, the liquid containing the polishing liquid can be prevented from solidifying on the inner surface and the outer surface of the atomizer cover, and further, contamination of the polished surface due to the fall of the solidified product can be prevented. Furthermore, even if the polishing liquid enters the inside of the top ring head cover, the top ring head cover and the top ring head are prevented from being contaminated by the polishing liquid, and the polishing liquid is prevented from being dripped onto the polishing surface and contaminating the polishing surface. be able to.

It is a perspective view showing the polish device concerning one embodiment of the present invention when the top ring is in the polish position above the polish table, and the dresser is in the dressing position above the polish table. FIG. 2 is a front view showing the polishing apparatus shown in FIG. 1 together with a spray nozzle when the top ring is in a substrate delivery position on the side of the polishing table and the dresser is in a retracted position on the side of the polishing table. FIG. 2 is a plan view showing the polishing apparatus shown in FIG. 1 together with a spray nozzle when the top ring is in a substrate delivery position on the side of the polishing table and the dresser is in a retracted position on the side of the polishing table. It is a front view which shows the atomizer with which the grinding | polishing apparatus shown in FIG. 1 is equipped with the spray nozzle. It is a perspective view which shows the polishing liquid supply nozzle with which the polishing apparatus shown in FIG. 1 is equipped with the spray nozzle. It is sectional drawing which shows the waterproof plate provided in the surrounding wall of a chamber. It is a perspective view which shows the grinding | polishing apparatus which concerns on other embodiment of this invention. It is a front view of the atomizer cover which shows an atomizer head with an imaginary line. It is a bottom view of an atomizer cover. FIG. 9 is a left side view of FIG. 8. It is a right view of FIG. It is a front view which expands and shows the lower cover of a top ring head cover. It is AA sectional view taken on the line of FIG. It is a longitudinal cross-sectional view of a 2nd dresser head cover. It is a perspective view which shows the detail of a polishing liquid supply nozzle.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a polishing apparatus according to an embodiment of the present invention. FIG. 1 shows a state in which the top ring 14 is in a polishing position above the polishing table 12 and the dresser 20 is in a dressing position above the polishing table 12. In FIG. 1, all the spray nozzles are omitted.

  As shown in FIG. 1, this polishing apparatus includes a polishing pad 10 having an upper surface as a polishing surface 10a, a polishing table 12 with the polishing pad 10 attached to the upper surface, and a substrate (object to be polished) such as a wafer as the polishing pad 10. A top ring head 16 having a top ring 14 that is slidably brought into contact with the polishing surface (upper surface) 10a of the polishing pad 10 and a dresser head 22 having a dresser 20 for dressing the polishing surface 10a of the polishing pad 10. Yes. The polishing table 12 is connected to a motor (not shown), and the motor rotates the polishing table 12 and the polishing pad 10 in the direction indicated by the arrow.

  A main portion of the top ring head 16 excluding the top ring 14 is surrounded by a top ring head cover 24. The top ring head 16 is connected to the upper end of a rotatable top ring head swing shaft 26. The top ring head swinging shaft 26 extends upward through the bottom plate of the top ring head cover 24. The top ring 14 is connected to the lower end of a top ring drive shaft 28 that extends downward through the bottom plate of the top ring head cover 24. The lower surface of the top ring 14 constitutes a substrate holding surface that holds the substrate by vacuum suction or the like.

  The top ring 14 is moved by the swing of the top ring head 16 as the top ring head swing shaft 26 rotates, and the polishing position immediately above the polishing table 12 shown in FIG. 1 and the polishing shown in FIGS. It moves between the substrate delivery positions on the side of the table 12.

  The main part of the dresser head 22 excluding the dresser 20 is surrounded by three dresser head covers, that is, a first dresser head cover 30a, a second dresser head cover 30b, and a third dresser head cover 30c. The dresser head 22 is connected to the upper end of a rotatable dresser head swing shaft 32 that extends upward through the bottom plate of the first dresser head cover 30a. The dresser 20 is connected to the lower end of a dresser drive shaft 38 that extends downward through the bottom plate of the second dresser head cover 30b.

  The dresser 20 has a dressing position just above the polishing table 12 shown in FIG. 1 and the polishing table 12 shown in FIGS. 2 and 3 by the swing of the dresser head 22 as the dresser head swing shaft 32 rotates. Move between the side retracted positions.

  Adjacent to the polishing table 12, the cleaning surface 10a of the polishing pad 10 is sprayed (sprayed) with a cleaning fluid such as a mixed fluid of liquid (for example, pure water) and gas (for example, nitrogen gas) or a liquid (for example, pure water). And an atomizer 40 for cleaning the polishing surface 10a. The upper surface of the atomizer 40 is composed of an atomizer cover 42. The lower surface of the atomizer 40 is provided with a number of jets (not shown) for jetting the cleaning fluid downward at predetermined intervals along the longitudinal direction. The atomizer 40 is connected to the upper end of the atomizer rocking shaft 44. With the rotation of the atomizer rocking shaft 44, the retreat position located on the side of the polishing table 12 shown by the solid line in FIG. It swings between a cleaning position above the polishing table 12 indicated by an imaginary line.

  A polishing liquid supply nozzle 46 for supplying a polishing liquid (slurry) from the supply port 46 a at the tip to the polishing surface 10 a of the polishing pad 10 is disposed adjacent to the polishing table 12. The polishing liquid supply nozzle 46 is connected to the upper end of the nozzle rocking shaft 48, and the polishing liquid in which the supply port 46 a shown in FIG. 1 is located above the polishing table 12 as the nozzle rocking shaft 48 rotates. It swings between a supply position and a retreat position (not shown) where the supply port 46a is located on the side of the polishing table 12. In this example, the polishing liquid supply nozzle 46 is configured by collecting a plurality of polishing liquid tubes into one pipe 50.

  The polishing table 12, the top ring head 16, the dresser head 22, the atomizer 40, and the polishing liquid supply nozzle 46 are connected to the operation control unit 5, and the operation of these devices is controlled by the operation control unit 5.

  As shown in FIGS. 2 and 3, the polishing apparatus is accommodated in the chamber 52. Inside the chamber 52, a spray nozzle that sprays cleaning liquid such as pure water on the inner wall surface of the chamber 52, that is, a ceiling wall spray nozzle 54 that sprays cleaning liquid on the ceiling wall 52a, and a peripheral wall spray that sprays cleaning liquid on the peripheral wall 52b. A nozzle 56 is disposed.

  Inside the chamber 52, a top ring spray nozzle 58 for spraying a cleaning liquid onto the upper surface of the top ring 14 when the top ring 14 is at the substrate delivery position on the side of the polishing table 12 is disposed. The top ring spray nozzle 58 is disposed on the upper side of the top ring 14 at the substrate delivery position. Further, a spray nozzle that sprays the cleaning liquid on the outer surface of the top ring head cover 24, that is, an upper spray nozzle 60 that sprays the cleaning liquid obliquely from above on the side of the top ring head cover 24 on the polishing table side, and a polishing table side of the top ring head cover 24. A side spray nozzle 62 for spraying the cleaning liquid in the horizontal direction toward the side surface is disposed. The upper spray nozzle 60 has a number of jet outlets 60a along the longitudinal direction thereof, and is arranged in the horizontal direction.

  Inside the chamber 52, when the dresser 20 is in a retracted position on the side of the polishing table 12, the spray nozzle for spraying the cleaning liquid onto the outer surface of the dresser head covers 30a, 30b, 30c, that is, the polishing of the dresser head covers 30a, 30b, 30c. An upper spray nozzle 64 that sprays the cleaning liquid obliquely from above on the side surface on the table side, and a side spray nozzle 66 that sprays the cleaning liquid in a horizontal direction toward the polishing table side surface of the dresser head covers 30a, 30b, and 30c are arranged. Yes. The upper spray nozzle 64 has a large number of jets 64a along the longitudinal direction thereof and is arranged in the horizontal direction.

  As shown in FIG. 4, a bracket 70 that rotates integrally with the atomizer swing shaft 44 is connected to the upper end of the atomizer swing shaft 44. The bracket 70 is provided with a spray nozzle 72 that sprays the cleaning liquid over the entire area of the atomizer cover 42 when the atomizer cover 42 is positioned at both the cleaning position and the retracted position. In this example, two spray nozzles 72 are provided.

  As shown in FIG. 5, a bracket 74 that rotates integrally with the nozzle swing shaft 48 is connected to the upper end of the nozzle swing shaft 48. When the supply port 46 a of the polishing liquid supply nozzle 46 is located at the side retracted position of the polishing table 12, the cleaning liquid is sprayed on the bracket 74 over the entire area of the polishing liquid supply nozzle 46, that is, on the outer surface of the pipe 50. A spray nozzle 76 is attached. In this example, two spray nozzles 76 are provided.

  Operations of the spray nozzles 54, 56, 58, 60, 62, 64, 66, 72, and 76 including the start and stop of the cleaning liquid spray are controlled by the operation control unit 5.

  Hereinafter, an operation sequence of the above-described polishing apparatus will be described. This operation sequence is controlled by the operation control unit 5 in accordance with an operation recipe preset in the operation control unit 5. The top ring 14 receives the substrate when it is in the substrate delivery position, moves the top ring 14 to the polishing position above the polishing table 12, then lowers the substrate while rotating it, and polishes the polishing surface of the rotating polishing pad 10 The substrate is polished by bringing the substrate into sliding contact with 10a. At the time of this polishing, the polishing liquid is supplied to the polishing surface 10a from the polishing liquid supply nozzle 46 moved from the retracted position to the polishing liquid supply position.

  After the polishing of the substrate is completed, the top ring 14 is raised. Further, the top ring 14 is moved to the substrate delivery position on the side of the polishing table 12, and the polished substrate is delivered to the next step. At the same time, the polishing liquid supply nozzle 46 is moved from the polishing liquid supply position to the retracted position.

  After the polishing of the substrate is completed, the dresser 20 is moved from the retracted position to the dressing position. Further, the dresser 20 is lowered while rotating, and the lower surface of the dresser 20 is brought into sliding contact with the polishing surface 10a of the rotating polishing pad 10, thereby dressing the polishing surface 10a. After the dressing of the polishing surface 10a is completed, the dresser 20 is moved from the dressing position to the retracted position.

  Further, the atomizer 40 is moved from the retracted position to the cleaning position, and then the cleaning fluid is ejected from the atomizer 40 onto the polishing surface 10a of the polishing pad 10, thereby cleaning the polishing surface 10a. Then, when the cleaning of the polishing surface 10a is completed, the atomizer 40 is moved from the cleaning position to the retracted position. In this example, the atomizer 40 can be moved from the cleaning position to the retracted position, but the atomizer 40 may be fixed at the cleaning position.

  When the top ring 14 is in the substrate transfer position, the cleaning liquid is sprayed on the top surface of the top ring 14 from the top ring spray nozzle 58 disposed on the upper side of the top ring 14, and at the same time, disposed around the top ring head cover 24. The cleaning liquid is sprayed from the upper spray nozzle 60 and the side spray nozzle 62 onto the outer surface of the top ring head cover 24. Thereby, the upper surface of the top ring 14 and the outer surface of the top ring head cover 24 are kept wet with the sprayed cleaning liquid. Thus, by keeping the wet state with the cleaning liquid, even if the polishing liquid comes into contact with the wet surface, the polishing liquid can be prevented from adhering to the surface, and the polishing liquid can be dried. Can be prevented. Further, when the top ring 14 is located at the substrate delivery position, the cleaning liquid is sprayed from the top ring spray nozzle 58, the upper spray nozzle 60, and the side spray nozzle 62. And the polishing performance of the polishing pad 10 is not affected.

  Before the top ring 14 moves from the substrate delivery position to the polishing position, spraying of the cleaning liquid from the top ring spray nozzle 58, the upper spray nozzle 60, and the side spray nozzle 62 is stopped. As described above, the operation control unit 5 controls the start and stop of spraying of the cleaning liquid from the spray nozzles 58, 60, 62 based on the position of the top ring 14.

  When the dresser 20 is in the retracted position on the side of the polishing table 12, the upper spray nozzle 64 and the side spray nozzle 66 arranged around the dresser head covers 30a, 30b, 30c are disposed on the outer surfaces of the dresser head covers 30a, 30b, 30c. Spray the cleaning solution. As a result, the outer surfaces of the dresser head covers 30a, 30b, 30c are kept wet with the sprayed cleaning liquid. Thus, by keeping the wet state with the cleaning liquid, even if the polishing liquid comes into contact with the wet surface, the polishing liquid can be prevented from adhering to the surface, and the polishing liquid can be dried. Can be prevented.

  Before the dresser 20 moves from the retracted position to the dressing position, spraying of the cleaning liquid from the upper spray nozzle 64 and the side spray nozzle 66 is stopped. As described above, the operation control unit 5 controls the start and stop of spraying of the cleaning liquid from the upper spray nozzle 64 and the side spray nozzle 66 based on the position of the dresser 20.

  When the atomizer 40 at the cleaning position sprays a cleaning fluid such as a mixed fluid or a liquid onto the polishing surface 10a to clean the polishing surface 10a, the dresser 20 moves the polishing surface 10a while the atomizer 40 is positioned at the retracted position. The cleaning liquid is sprayed from the spray nozzle 72 onto the outer surface of the atomizer cover 42 when the substrate is not actually polished, including when dressing. Thereby, the outer surface of the atomizer cover 42 is kept wet with the sprayed cleaning liquid. Thus, by keeping the wet state with the cleaning liquid, even if the polishing liquid comes into contact with the wet surface, the polishing liquid can be prevented from adhering to the surface, and the polishing liquid can be dried. Can be prevented.

  In particular, when the polishing surface 10a is cleaned by spraying the cleaning surface 10a from the atomizer 40, the cleaning fluid splashed from the polishing surface 10a by spraying the cleaning liquid from the spray nozzle 72 onto the outer surface of the atomizer cover 42. Can be prevented from adhering to the atomizer cover 42.

  When the substrate is being polished on the polishing pad 10, the cleaning liquid is not sprayed onto the atomizer cover 42. As described above, the operation control unit 5 controls the start and stop of spraying of the cleaning liquid from the spray nozzle 72 based on whether or not the substrate is polished.

  As described above, the atomizer 40 may be fixed at the cleaning position, and the cleaning liquid may be sprayed from the spray nozzle 72 onto the outer surface of the atomizer cover 42 when the substrate is not polished. The cleaning liquid covering the atomizer cover 42 can prevent the liquid on the polishing pad 10 from being scattered during the dressing and adhering to the atomizer 40. In this case, the cleaning liquid sprayed from the spray nozzle 72 falls on the polishing pad 10, but the cleaning liquid is removed by the cleaning fluid simultaneously supplied from the atomizer 40 to the polishing surface 10a. It will not remain on top.

  The polishing liquid supply nozzle 46 includes the time when the polishing surface 10a is cleaned by spraying a cleaning fluid such as a mixed fluid or liquid from the atomizer 40 onto the polishing surface 10a, and the time when the polishing surface 10a is dressed by the dresser 20. When the substrate is located at the retracted position and the substrate is not actually polished, the cleaning liquid is sprayed from the spray nozzle 76 onto the polishing liquid supply nozzle 46, that is, the pipe 50. Thus, the polishing liquid supply nozzle 46, that is, the outer surface of the pipe 50 is kept wet with the sprayed cleaning liquid. Thus, by keeping the wet state with the cleaning liquid, even if the polishing liquid comes into contact with the wet surface, the polishing liquid can be prevented from adhering to the surface, and the polishing liquid can be dried. Can be prevented.

  Before the polishing liquid supply nozzle 46 moves from the retracted position to the polishing liquid supply position, spraying of the cleaning liquid from the spray nozzle 76 is stopped. As described above, the operation control unit 5 controls the start and stop of the spray of the cleaning liquid from the spray nozzle 76 based on the position of the polishing liquid supply nozzle 46.

  In this example, the polishing liquid supply nozzle 46 can be moved from the polishing liquid supply position to the retracted position. However, like the above-described atomizer 40, the polishing liquid supply nozzle 46 is fixed to the polishing liquid supply position. Also good. In this case, when the polishing surface 10a is cleaned by spraying the cleaning fluid from the atomizer 40 to the polishing surface 10a, or when the polishing surface 10a is dressed by the dresser 20, the polishing liquid supply located at the polishing liquid supply position is provided. The polishing liquid supply nozzle 46 can be kept wet by spraying the cleaning liquid onto the nozzle 46.

  Further, when the substrate is not actually polished, the cleaning liquid is sprayed from the ceiling wall spray nozzle 54 to the ceiling wall 52 a of the chamber 52 and from the peripheral wall spray nozzle 56 to the peripheral wall 52 b of the chamber 52. Thus, the ceiling wall 52a and the peripheral wall 52b constituting the inner wall surface of the chamber 52 are kept wet with the cleaning liquid. Thus, by keeping the wet state with the cleaning liquid, even if the polishing liquid comes into contact with the wet surface, the polishing liquid can be prevented from adhering to the surface, and the polishing liquid can be dried. Can be prevented.

  When the substrate is being polished on the polishing pad 10, the cleaning liquid is not sprayed on the ceiling wall 52 a and the peripheral wall 52 b of the chamber 52. As described above, the operation control unit 5 controls the start and stop of spraying of the cleaning liquid from the ceiling wall spray nozzle 54 and the peripheral wall spray nozzle 56 based on whether or not the substrate is polished.

  As shown in FIG. 6, the waterproof plate 84 may be provided at a predetermined position on the peripheral wall 52 b of the chamber 52. The waterproof plate 84 includes a flat support plate 80 and a plurality of folded plates 82 attached to the support plate 80 at predetermined intervals along the vertical direction. Each folded plate 82 is inclined downward. The waterproof plate 84 configured in this way can prevent the airflow from the polishing pad 10 from rebounding.

  According to this polishing apparatus, the components arranged around the polishing table 12 such as the upper surface of the top ring 14, the outer surface of the top ring head cover 24, and the outer surfaces of the dresser head covers 30a, 30b, 30c are subjected to various processes such as polishing. It can be kept in a wet state without affecting the water content. As a result, it is possible to prevent the polishing liquid from adhering to the components arranged around the polishing table 12 and drying, and the dried polishing liquid falls on the polishing table 12 to generate scratches on the substrate. Can be prevented.

  The start and stop of spraying of the cleaning liquid from all the spray nozzles described above are executed according to the operation recipe set in the operation control unit 5. The cleaning liquid supplied from these spray nozzles can keep the above components wet even when the polishing apparatus is in idle operation (standby operation). The idle operation of the polishing apparatus is a standby operation when polishing of a substrate is not performed for a relatively long time. For example, after polishing of all the substrates in one lot is completed, There is a standby operation until the polishing of the substrate is started.

  In order to make it difficult for the polishing liquid or the like to adhere, a water repellent coat may be applied to some or all of the components arranged around the polishing table 12.

  FIG. 7 is a perspective view showing a polishing apparatus according to another embodiment of the present invention. Since the configuration and operation that are not particularly described are the same as the configuration and operation of the embodiment shown in FIG. In FIG. 7, the illustration of the operation control unit 5 is omitted.

  As shown in FIG. 7, the atomizer 40 atomizes a cleaning fluid such as a mixed fluid of liquid (for example, pure water) and gas (for example, nitrogen gas) or a liquid (for example, pure water) on the polishing surface 10a of the polishing pad 10. An atomizer head 89 (see FIG. 8) that cleans the polishing surface 10a by spraying (including spraying) and an atomizer cover 42 that covers the upper surface of the atomizer head 89 are provided. On the lower surface of the atomizer head 89, a plurality of spray nozzles 89a (see FIG. 8) for ejecting the cleaning fluid downward are provided at predetermined intervals along the longitudinal direction. The atomizer 40 is connected to the upper end of the atomizer rocking shaft 44. With the rotation of the atomizer rocking shaft 44, a retracted position located on the side of the polishing table 12 shown by a solid line in FIG. It swings between a cleaning position above the polishing table 12 indicated by an imaginary line.

8 to 11 show the atomizer cover 42. 8 and 9, the left side is the proximal end side of the atomizer cover 42, and the right side is the distal end side of the atomizer cover 42. As shown in FIGS. 8 to 11, the atomizer cover 42 has a first top plate 90 a having a constant radius R ₁ and a quarter-circular longitudinal section, and a radius that gradually decreases from the proximal end toward the distal end. , that is, a second top plate 90b having a radius _{R 2} on the base end side is larger than the radius _{R 3} of the distal radius _{(R 2>} R 3) 1/4 £ shaped longitudinal section. The top of the first top plate 90a and the top of the second top plate 90b are connected to each other to form a semi-cylindrical semi-cylindrical top plate 90. The semicylindrical top plate 90 has a semicircular longitudinal section. Further, the atomizer cover 42 has two side plates that slid smoothly and vertically from both lower ends of the semicylindrical top plate 90, that is, a first side plate 92 and a second side plate 94. The upper end of the first side plate 92 is integrally connected to the lower end of the first top plate 90a, and the upper end of the second side plate 94 is integrally connected to the lower end of the second top plate 90b.

  The first top plate 90 a, the second top plate 90 b, and the side plates 92 and 94 form a space 96 having an open lower end in the atomizer cover 42. When an imaginary plane passing through the top of the first top plate 90a and the top of the second top plate 90b (that is, the top of the semi-cylindrical top plate 90) in the vertical direction is defined as a vertical plane YY, the space 96 in the atomizer cover 42 has a vertical plane. The width a from YY to the first side plate 92 is constant, and the width b from the vertical plane YY to the second side plate 94 gradually decreases from the base end to the tip. The space 96 in the atomizer cover 42 is asymmetric about the vertical plane YY. In this space 96, as shown in FIG. 8, a cleaning fluid such as a mixed fluid of liquid (for example, pure water) and gas (for example, nitrogen gas) or a liquid (for example, pure water) is sprayed on the polishing surface 10a in a mist form. Then, the atomizer head 89 having the spray nozzle 89 a for cleaning the polishing surface 10 a is covered with the atomizer cover 42 and stored.

  In this example, the semi-cylindrical top plate 90 is formed by connecting the first top plate 90a and the second top plate 90b, both of which have a quarter-circular longitudinal section, at the top portion. The first top plate and the second top plate may be connected to each other at their tops to form a semi-cylindrical top plate.

  The second side plate 94 connected to the second top plate 90b is integrally provided with a projecting portion 98 whose outward projecting amount gradually decreases from the proximal end toward the distal end. The protrusion 98 serves to prevent the cleaning fluid that is wound up from the polishing pad 10 from diffusing into the chamber 52 (see FIG. 2) when the cleaning fluid is sprayed onto the polishing pad 10 from the spray nozzle 89a. The lower end surface 94a of the portion of the second side plate 94 where the protruding portion 98 is not formed and the lower end surface 98a of the protruding portion 98 are continuously connected. In this example, the protruding portion 98 is provided only on the second side plate 94 connected to the second top plate 90b, but the protruding portion may also be provided on the first side plate 92 connected to the first top plate 90a. .

  As shown in FIG. 8, the lower end surface 92 a of the first side plate 92 has a gradient that inclines downward from the front end of the atomizer cover 42 toward the base end with respect to the horizontal plane XX. Similarly, the lower end surface 94a of the second side plate 94 and the lower end surface 98a of the projecting portion 98 connected to each other have a slope inclined downward from the distal end toward the proximal end.

  The atomizer cover 42 is integrally formed of a resin such as polyvinyl chloride. The draft in the integral molding of resin is, for example, 1.5 °. That is, in FIG. 10, the vertical portion 92A of the first side plate 92 connected to the first top plate 90a and the vertical portion 94B of the second side plate 94 connected to the second top plate 90b are not parallel to each other. The distance gradually increases along the downward direction. The atomizer cover 42 has such a shape that can be integrally molded with resin.

  A rectangular nor seal 100 is attached to the rear surface of the top side of the top plate 90 of the atomizer cover 42, and a bolt fitting 102 is attached to a notch provided on the base end side. An elongated hole 102 a extending in the longitudinal direction of the atomizer cover 42 is provided inside the bolt attachment 102.

  The atomizer cover 42 is inserted into a long hole 102a of the bolt attachment 102 by inserting a shaft portion of a bolt (not shown) and tightening the bolt to bring the head of the bolt into contact with the bolt attachment 102. It is fixed with a bolt. The attachment position along the longitudinal direction of the atomizer cover 42 is finely adjusted through the long hole 102a.

  The atomizer cover 42 has a smooth shape with no corners that is easy to flow down even when liquid contacts the inner or outer surface. With such a shape, the atomizer cover 42 can be prevented from being contaminated with the liquid containing the polishing liquid, and the wiping property of the liquid containing the polishing liquid attached to the atomizer cover 42 can be improved. In addition, by making the atomizer cover 42 a smooth shape without corners, integral molding with resin becomes possible.

  As described above, the lower end surface 92a of the first side plate 92 connected to the first top plate 90a is inclined downward from the front end to the base end of the atomizer cover 42 with respect to the horizontal plane XX. Similarly, the lower end surface 94a of the second side plate 94 connected to the second top plate 90b and the lower end surface 98a of the protruding portion 98 are inclined downward from the distal end of the atomizer cover 42 toward the proximal end. The liquid flows down from the semi-cylindrical top plate 90 of the atomizer cover 42 to the side plates 92 and 94, and further flows down on the protruding portion 98 to reach the lower end surfaces 92 a and 94 a of the side plates 92 and 94 and the lower end portion 98 a of the protruding portion 98. . Since the lower end surfaces 92a, 94a, and 98a are inclined with respect to the horizontal plane XX, the liquid flows on the lower end surfaces 92a, 94a, and 98a from the distal end of the atomizer cover 42 toward the proximal end.

  Furthermore, the atomizer cover 42 can be reinforced by the projecting portion 98 by providing the projecting portion 98 integrally with the second side plate 94 connected to the second top plate 90b.

  As shown in FIG. 7, the top ring head cover 24 includes a side cover 112 having a side plate 110 and a lower cover 114 that closes a lower end opening of the side cover 112. FIG. 12 shows details of the lower cover 114. As shown in FIG. 12, the lower cover 114 has a bottom plate 116 and a side plate 118 that extends upward from the outer periphery of the bottom plate 116 and surrounds the periphery of the top ring head 16 together with the side plate 110 of the side cover 112. ing. The top ring 14 is connected to the lower end of a top ring drive shaft 28 that penetrates the bottom plate 116 of the lower cover 114 and extends downward.

  The bottom plate 116 of the lower cover 114 has a slope that is inclined downward toward the outer side in the radial direction of the polishing table 12 when the top ring 14 is in a polishing position above the polishing surface 10a. That is, the bottom plate 116 of the lower cover 114 has a slope that is inclined downward toward the top ring head swinging shaft 26.

  The polishing liquid that has entered the top ring head cover 24 reaches the bottom plate 116 of the lower cover 114, flows along the gradient of the bottom plate 116, and is collected on the side of the polishing table 12. Accordingly, it is possible to prevent the top ring head cover 24 and the top ring head 16 from being contaminated by the polishing liquid, or the polishing liquid from dripping onto the polishing surface 10a and contaminating the polishing surface 10a.

  FIG. 13 is an enlarged sectional view taken along line AA in FIG. As shown in FIG. 13, the nor seal 120 is attached to the back surface of the side plate 118 and the side plate 110 with the upper end surface of the side plate 118 of the lower cover 114 in contact with or close to the lower end surface of the side plate 110 of the side cover 112. Yes. The gap between the side plates 110 and 78 is sealed by the nor seal 120. With such a structure, the connecting portion between the side cover 112 and the lower cover 114 can be positioned above the corner between the side cover 112 and the lower cover 114. If the connecting portion between the side cover 112 and the lower cover 114 exists at the corner, the polishing liquid tends to stay in the corner. The configuration shown in FIG. 13 can solve such a problem. Further, the nor seal 120 can prevent the polishing liquid from entering the top ring head cover 24.

  FIG. 14 is a longitudinal sectional view of the second dresser head cover 30b. As shown in FIG. 14, the second dresser head cover 30 b includes a substantially cylindrical upper side plate 122 and a lower side plate 124. A tape 126 is attached to the outer peripheral surfaces of the upper side plate 122 and the lower side plate 124 with the lower end surface of the upper side plate 122 in contact with or close to the upper end surface of the lower side plate 124. The gap between the upper side plate 122 and the lower side plate 124 is sealed by the tape 126. A cushioning member 132 is disposed between the ridge 128 attached to the inner peripheral surface of the upper side plate 122 and the ridge 130 attached to the inner peripheral surface of the lower side plate 124. With such a structure, the connecting portion between the upper side plate 122 and the lower side plate 124 can be moved upward, and liquid can be prevented from entering the second dresser head cover 30b.

  A curved surface portion 120 a that smoothly connects the vertical portion of the upper side plate 122 to the horizontal portion is formed on the upper side plate 122. With such a curved surface portion 120a, water droplets can smoothly flow on the outer surface of the upper side plate 122.

  A configuration similar to that of the second dresser head cover 30b may be adopted for the first dresser head cover 30a.

  FIG. 15 shows details of the polishing liquid supply nozzle 46. As shown in FIG. 15, the polishing liquid supply nozzle 46 is configured by collecting a plurality of polishing liquid tubes 134 into one pipe 50. Accordingly, it is possible to prevent the polishing liquid from entering the gap between the polishing liquid tubes 134 and improve the cleaning performance of the polishing liquid supply nozzle 46.

  The embodiment described above is described for the purpose of enabling the person having ordinary knowledge in the technical field to which the present invention belongs to implement the present invention. Various modifications of the above embodiment can be naturally made by those skilled in the art, and the technical idea of the present invention can be applied to other embodiments. Therefore, the present invention should not be limited to the described embodiments, but should be the widest scope according to the technical idea defined by the claims.

DESCRIPTION OF SYMBOLS 5 Operation control part 10 Polishing pad 10a Polishing surface 12 Polishing table 14 Top ring 16 Top ring head 20 Dresser 22 Dresser head 24 Top ring head cover 30a, 30b, 30c Dresser head cover 40 Atomizer 42 Atomizer cover 46 Polishing liquid supply nozzle 50 Pipe 52 Chamber 54 ceiling wall spray nozzle 56 peripheral wall spray nozzle 58 top ring spray nozzle 60, 64 upper spray nozzle 62, 66 side spray nozzle 72, 76 spray nozzle 84 waterproof plate 89 atomizer head 90 semi-cylindrical top plate 90a first top plate 90b second top plate 92, 94 Side plate 96 Space 98 Projection 100 Nor seal 102 Bolt attachment 110 Side plate 112 Side cover 114 Lower cover 116 Bottom plate 118 Side plate 120 Nor seal 122 Upper side plate 1 4 lower plate 126 tape 132 cushioning material 134 polishing liquid tube

Claims (6)

A rotatable polishing table for supporting a polishing pad having a polishing surface;
An atomizer head for spraying a cleaning fluid onto the polishing surface to clean the polishing surface;
An atomizer cover covering the upper surface of the atomizer head;
The atomizer cover is
A semi-cylindrical top plate having a semi-cylindrical shape;
A first side plate and a second side plate extending downward from both lower ends of the semi-cylindrical top plate;
The semi-cylindrical top plate is
A first top plate having an arcuate longitudinal section with a constant radius from the base end to the tip of the atomizer cover;
A second top plate having an arcuate longitudinal section with a gradually decreasing radius from the base end to the tip of the atomizer cover;
A polishing apparatus, wherein a top part of the first top plate and a top part of the second top plate are connected to each other to form the semi-cylindrical top plate. The polishing apparatus according to claim 1 , wherein the semi-cylindrical top plate, the first side plate, and the second side plate are integrally formed of resin. The lower end surface of the first side plate and said second side plate, the polishing apparatus according to claim 1, characterized in that inclined downward toward the base end from the tip of the atomizer cover. The second side plate is connected to the second top plate;
The polishing apparatus according to claim 1 , wherein the second side plate is provided with a protruding portion that protrudes in a horizontal direction. A top ring head having a top ring pressed against the polishing surface while holding and rotating the substrate;
A top ring head cover surrounding the top ring head;
The top ring head cover has a side cover that surrounds the top ring head, and a lower cover that closes a lower end opening of the side cover,
It said lower cover, when the top ring is in a polishing position above the polishing table, according to claim 1, characterized in that it comprises a bottom plate which is inclined downward toward the outside in the radial direction of the polishing table Polishing equipment. The polishing apparatus according to claim 5 , wherein the lower cover includes a side plate that extends upward from an outer peripheral portion of the bottom plate and contacts or approaches the side plate of the side cover.

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