JP2017204523A - Polishing member and polishing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polishing member and a polishing method, capable of smoothly polishing a raw material to be processed from a peripheral end side face up to the main surface regardless of the shape.SOLUTION: A polishing member 10 polishes a peripheral end side face 36 and/or the main surfaces 32, 34 by being rotated in contact with the peripheral end side face 36 of a wafer 30 being a raw material to be processed and/or the main surfaces 32, 34. Then, the polishing member 10 has a polishing cloth 12 having flexibility and on the surface of the polishing cloth 12, a granular polishing material is carried.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a polishing member and a polishing method applied to an apparatus having a polishing function used in a semiconductor manufacturing process and the like, and more specifically, smooth from the peripheral side surface to the main surface of a workpiece such as a silicon wafer. The present invention relates to a polishing member and a polishing method.

  In recent years, with the miniaturization of semiconductor devices, improvement in yield in wet processing such as etching, polishing, and cleaning has become an important issue. For example, in a cleaning apparatus, in order to remove contaminants and particles adhering to the surface of, for example, a semiconductor wafer (hereinafter simply referred to as a wafer) as an object to be cleaned, in a horizontal direction (vertical direction) or a vertical direction (horizontal direction) By rotating the cylindrical brush on the wafer placed in contact with the cylindrical side surface as the contact surface, the main surface and peripheral side surface of the wafer rotating as the brush rotates are rubbed with the brush in one direction. A brush scrub device that scrapes out is conventionally known (for example, see Patent Document 1).

  In addition to cleaning, when polishing a wafer as a material to be processed, for example, in a state where a plurality of wafers are overlapped with a spacer interposed between the wafers, A batch-type process in which end surfaces are polished together and a single-wafer process in which wafers are processed one by one (for example, see Patent Document 2) are also performed.

JP2015-225945A JP 2002-307276 A

  When a workpiece such as a wafer is polished, it is important to polish it to a smooth surface. This is because, if polishing cannot be performed smoothly and defective parts such as irregularities and edges remain after processing, damage is likely to start from the defective parts, or foreign substances are likely to adhere to the defective parts. .

  However, in the batch-type polishing process described above, the peripheral edge side surfaces of a large number of wafers are polished together by a relatively hard polishing member such as a grindstone. Edges are likely to occur at the boundary with the wide surface and the back surface (that is, it is difficult to polish each wafer smoothly from the peripheral side surface to the main surface), and therefore, foreign objects adhere to such edges. easy. Further, foreign matters may further adhere in the spacer removing operation after processing. Further, in a situation where the wafers are manually stacked one by one and the batch processing is performed, the wafers are likely to vary in the polishing state due to wafer misalignment, and the occurrence of edges is, of course, the yield. It tends to cause a decline.

  On the other hand, the single wafer type polishing process can be expected to improve the yield compared to the batch type process, but as disclosed in Patent Document 2, the peripheral end side surface of the wafer is provided with one notch polishing member and one peripheral polishing side. When polishing from four different types of polishing members, that is, a side polishing member and two bevel polishing members, the setting of processing conditions is complicated and easily fluctuated, and the wafer is easily damaged. In addition, since the polishing by the four polishing members is chamfered in stages, it is difficult to smooth the connection between the processed surfaces at each stage. That is, it is difficult to smoothly polish the wafer from the peripheral side surface to the main surface, and foreign substances are likely to adhere to the rough surface portion.

  In both the batch type and the single wafer type, particularly when the peripheral side surface of the wafer is polished as a material to be processed, the orientation is a notch or flat surface notch for defining the crystal axis direction of the wafer. Due to the presence of an orientation flat (hereinafter abbreviated as orientation flat), the polishing member polishing the peripheral side surface of the wafer cannot sufficiently contact the wafer at the orientation flat portion. Wafer polishing may be insufficient or impossible.

  The present invention has been made by paying attention to the above-described problems, and is applied to an apparatus having a polishing function used in a semiconductor manufacturing process or the like, from a peripheral end side surface to a main surface regardless of its shape. An object of the present invention is to provide a polishing member and a polishing method that can be polished smoothly.

  In order to achieve the above-described object, the polishing member according to the present invention rotates the peripheral end side surface and / or main surface of the material to be processed by contacting and rotating the peripheral end side surface and / or main surface. The polishing member has a flexible polishing cloth, and a granular abrasive is carried on the surface of the polishing cloth.

  According to the configuration described above, since the polishing cloth of the polishing member has flexibility, it can be circulated from the peripheral end side surface of the work material to the main surface by the deformation, and the peripheral end side surface and main surface of the work material The material to be processed can be smoothly polished from the peripheral side surface to the main surface without causing an edge at the boundary. Thus, if the workpiece material can be smoothly polished from the peripheral side surface to the main surface and no edge is generated, adhesion of foreign matters can be avoided. In addition, when the polishing member (polishing cloth) is deformed during polishing, there is a setting failure including deviation from the predetermined processing position of the workpiece material regardless of the processing type such as batch type or single wafer type. Even so, such a defective factor is absorbed, and smooth polishing from the peripheral side surface of the workpiece material to the main surface is enabled. Therefore, not only the manual process but also the polishing process can be automated, which can contribute to the improvement of the yield.

  In addition, since the polishing member can be deformed, even if the workpiece material has an irregular shape, such as a wafer having an orientation flat, it is always applied with a desired pressure to the peripheral side surface over the entire circumference of the workpiece material. Can touch. In other words, according to the present invention, the workpiece material can be smoothly polished over the entire circumference from the peripheral end side surface to the main surface regardless of its shape.

  In addition, the polishing member according to the present invention is configured to polish the peripheral end side surface by rotating in contact with the peripheral end side surface of the material to be processed, and is mounted on the outer periphery of the rotatable support member and the support member. A polishing cloth that is attached and carries an abrasive on the surface, and the polishing cloth is deformable by being in pressure contact with the workpiece.

  Even in such a polishing member, since the polishing cloth can be deformed when it comes into pressure contact with the work material, the deformation can wrap around from the peripheral side surface of the work material to the main surface. The workpiece material can be smoothly polished from the peripheral end side surface to the main surface without causing an edge at the boundary between the peripheral end side surface and the main surface.

  In the configuration described above, it is preferable that the polishing cloth is detachably (replaceable) attached to the support member. Thus, only the polishing cloth needs to be replaced when the abrasive is consumed, and the processing cost (and thus the manufacturing cost) can be reduced. Moreover, in the said structure, it is preferable that a polishing member is movable so that the grinding | polishing position with respect to a workpiece material can be changed. In this case, the polishing member may be moved, for example, in a direction perpendicular to the main surface of the material to be processed (that is, a direction along the circumferential end side surface of the material to be processed), preferably in the longitudinal direction of the polishing member. In this way, the degree of wear of the polishing material can be made uniform throughout the polishing member, and the polishing member can be used evenly (the polishing cloth can be used efficiently and effectively by utilizing a wide range of polishing cloth). become). Further, in this case, if the polishing member is formed long in the longitudinal direction so that the workpiece can be polished at an arbitrary position along the longitudinal direction, the polishing member is longer than the conventional polishing member that does not move. It has excellent durability that can be used for a long time, and as a result, it is possible to ensure a stable quality with little variation in the workpiece material over a long period of time. Further, the polishing member may be tilted, and by doing so, smooth polishing from the peripheral end side surface to the main surface of the workpiece material is further facilitated.

  In the above configuration, the polishing cloth may be formed of, for example, a nonwoven fabric or a woven fabric. In addition, as a method of supporting the abrasive on the polishing cloth, for example, feather-like or flocked protrusions are formed on the surface of the polishing cloth, and the abrasive is attached (attached to bite into these feathered portions or protrusions). Various methods such as forming a plurality of protrusions separately and attaching the abrasive to the side surfaces of the protrusions, or attaching them to the surface so as not to bite in. . In this case, examples of the abrasive include particulate diamond and alumina.

  In this specification, the “main surface” is a surface including the front and back having the largest area among the surfaces constituting the material to be processed. For example, when the material to be processed is a semiconductor wafer It means the front and back surfaces of a wafer on which functional layers such as circuits and patterns including transistors and wirings are deposited. Further, in this specification, the “circumferential end side surface” means a side surface located at the outer peripheral end edge connecting the main surfaces of the workpiece material.

  Further, in order to achieve the above-described object, the present invention rotatably supports a work material while regulating the position of the work material by a support, and the peripheral surface of the work material supported by the support. The abrasive member is brought into press contact, and the abrasive member is deformed so that the peripheral side surface of the workpiece is bitten into the abrasive member, and the abrasive member is rotated in the bite and pressed state to rotate the abrasive member. Provided is a polishing method for polishing the peripheral end side surface of a workpiece.

  ADVANTAGE OF THE INVENTION According to this invention, the grinding | polishing member and grinding | polishing method which can grind | polish a workpiece material smoothly from a peripheral end side surface to a main surface irrespective of the shape are obtained.

The schematic plan view which shows the principal part structure of the apparatus which has a grinding | polishing function which concerns on one Embodiment of this invention. The side view which shows schematically the whole apparatus which has the grinding | polishing function of FIG. (A) is a plan view of the polishing member, (b) is a side view showing the polishing member in a vertical state facing the peripheral end side surface of the workpiece, and (c) is a state of (b). The side view which shows the state by which the grinding | polishing member was tilted from. The fragmentary sectional side view which shows the biting press state which makes a grinding | polishing member press-contact with the peripheral end side surface of a workpiece material, and deform | transforms a grinding | polishing member so that the circumferential end side surface of a workpiece material bites into a polishing member. (A) is a partial sectional side view showing an example of the state of polishing of the peripheral end side surface of the workpiece material polished by the polishing member, and (b) is polishing the peripheral end side surface of the workpiece material polished by the polishing member. The partial side cross-sectional part which shows the other example of a state. Schematic which shows an example which hold | maintained the abrasive material to the processus | protrusion of the surface of polishing cloth. It is the schematic which shows the state which pressed the wafer against the abrasive material member, (a) is a figure which shows the state pressed slightly, (b) is a figure which shows the state pressed strongly. The figure which shows embodiment from which the structure of a grinding | polishing member with respect to a wafer, and an arrangement | positioning aspect differ. (A)-(c) is a figure which shows the structural example of a disk-shaped grinding | polishing member, respectively. (A)-(c) is a figure which shows the example of arrangement | positioning of the polishing cloth which contacts with respect to a wafer, respectively.

Hereinafter, an embodiment of a polishing member and a polishing method according to the present invention will be described with reference to the drawings.
In the following description, a configuration example of a device having a polishing function for polishing a workpiece material (hereinafter also referred to as a device) will be described first, and then an embodiment of a polishing member used in such a device, A polishing method will be described. In the following description, a workpiece material to be polished is a perfect semiconductor wafer. However, when processing a workpiece material having a different shape, such as a semiconductor wafer having a non-circular contour with an orientation flat. The present invention is applicable.

  The apparatus 1 according to the present embodiment is, for example, a so-called inline processing apparatus, that is, a loader unit (not shown) in which a wafer 30 as a workpiece to be polished is loaded and accommodated, and the wafer 30 is rotated. 1 and FIG. 2 for polishing in the state of being processed, a cleaning unit (not shown) for cleaning the polished wafer 30, and for drying the cleaned wafer 30 And an unloader unit (not shown) for storing the washed and dried wafer 30 for unloading, and various internal transfer robots (not shown) have a wafer between each unit. It is comprised as a processing apparatus which carries in / out 30. Such an apparatus may be a single polishing apparatus composed of only the polishing section 5, and the structure arrangement form thereof is arbitrary. In any case, the wafer 30 to be polished is carried in and out of the apparatus 1 manually or automatically via a transfer robot.

  In the present embodiment, an example in which the wafer 30 is polished while being arranged in the horizontal direction in the apparatus 1 will be described. However, in the present invention, the wafer 30 is arranged not only in the horizontal direction but also in the vertical direction. The present invention can also be applied to a case where polishing is performed in various states such as a state, an obliquely disposed state, and an invertedly disposed state.

  As schematically shown in FIGS. 1 and 2, the polishing processing unit 5 of the apparatus 1 according to the present embodiment includes a support body 2 configured by, for example, a turntable that rotatably supports the wafer 30 while regulating the position of the wafer 30. And a polishing member 10 that polishes at least the peripheral side surface 36 by rotating at least the peripheral end side surface 36 of the wafer 30 supported by the support 2 by contacting (described later) the rotation. In this case, a plurality (four in this embodiment) of polishing members 10 are arranged at predetermined angular intervals (for example, equal angular intervals) along the outer periphery of the wafer 30 supported by the support 2.

  The wafer 30 has a first main surface 32 (hereinafter simply referred to as the front surface 32) that forms the surface, a second main surface 34 (hereinafter simply referred to as the back surface 34) that forms the back surface, and these surfaces 32. , 34 and the peripheral end side surface 36 located at the outer peripheral end surface connecting the two, and the support body 2 as a turntable is evacuated through, for example, the suction path 7, so that the back surface 34 of the wafer 30 is provided. Is adsorbed to support the wafer 30 and is itself rotationally driven during polishing. Further, the polishing member 10 is disposed so as not to block a transfer path of a transfer robot (not shown) or to be retractable from the transfer path (for example, by using an air cylinder, the polishing member 10 can be attached to and detached from the peripheral side surface 36 of the wafer 30). Can be moved to). In addition, all drive elements such as a motor for rotating the polishing member 10 and a control device for controlling the operation of the polishing member 10 are, for example, in the housing 70 that supports the polishing member 10 so that the polishing member 10 can be moved (rotated, translated, tilted). Be placed.

  Further, the apparatus 1 (polishing processing unit 5) of the present embodiment has the polishing member 10 in contact with the peripheral end side surface 36 of the wafer 30 supported on the support 2 facing the wafer 30 (for example, the center of the wafer 30). (Toward) A biasing mechanism that always biases is provided. In particular, in the present embodiment, the biasing mechanism pushes and pulls the interposition member 74 by the cylinder 72 and causes the biasing force of the biasing spring 76 to act on the polishing member 10 via a force transmission member (not shown) in the housing 70. Is realized. Alternatively, other urging forms such as a configuration in which a polishing cloth is applied to the wafer using the weight of the weight and the polishing cloth moves following a step such as an orientation flat so as to follow the shape may be employed. Further, it is preferable to provide a mechanism (for example, a combination mechanism of servo motor control and spring 76) that can adjust such an urging force (contact pressure between the wafer 30 and the polishing member 10). The urging mechanism that urges the polishing member 10 may be configured to press the polishing member against the wafer by a combination of its own weight and weight, for example.

  As shown in FIG. 3, the polishing member 10 includes a rotatable support member 14 and a polishing cloth 12 attached to the outer peripheral surface of the support member 14 and carrying an abrasive on the surface. In this case, the polishing cloth 12 has a continuous polishing surface, and has flexibility such that it can be deformed by contact with the wafer 30 by the urging force of the urging mechanism, and is constituted by, for example, a nonwoven fabric or a woven cloth. It is possible.

  Examples of the abrasive supported on the surface of the polishing cloth 12 include granular materials such as diamond, alumina, cerium oxide, or particulate abrasive grains (particle size is, for example, several microns to nano level). Can be mentioned. Such an abrasive is carried (including adhesion, adhesion, etc.) on the polishing cloth 12, and as a carrying method thereof, for example, feathered or flocked projections (see FIG. 4 and FIG. 6, various methods are conceivable, such as forming such feathers and protrusions indicated by reference numeral 16 (hereinafter referred to as protrusions 16) and attaching an abrasive to these protrusions 16. In this case, the granular abrasive can be adhered by various methods such as simply depositing on the surface, adhering to the polishing cloth during deposition, or pressing while applying pressure. Specifically, as shown in FIG. 6, if the polishing cloth is a non-woven fabric, a portion of the fiber 12F that is fluffed is sprinkled with an abrasive (abrasive grain) 17 so as to be deposited on the surface of the fiber 12F. Abrasive material adheres to (protrusions 16) and deposits in a state of being entangled with the surface portion. Alternatively, the abrasive 17 is bitten into the side surface of the protrusion 16 by pressing (including pressure bonding) the abrasive (abrasive abrasive grains) against the fluffy fibers or the protrusion formed on the surface of the polishing cloth. It is also possible to attach to the surface so that it does not bite. That is, the abrasive may be deposited in a layered manner on the surface of the polishing cloth (preferably deposited in a layered manner so that the surface is easily deformed) and may be held on both by adhering to the protruding portion, The position to be carried, the amount to be carried, the particle diameter, the material, and the like may be changed according to the relationship regarding the processing conditions between the peripheral end side surface of the wafer and the main surface (front and back). For example, it is preferable that the amount of polishing at the protrusion portion is smaller than that at the polishing cloth portion. Further, a polishing cloth or an abrasive can be selected so that the polishing member 10 can be used for both polishing and cleaning.

  In the present embodiment, the polishing pad 12 is detachably (replaceable) attached to the support member 14. In this case, the polishing cloth 12 may be wound around the entire circumference of the support member 14 with a single cloth, or may be joined by, for example, an oblique joining portion 19 as shown in FIG. It may be divided into a plurality of sheets and separately attached to the support member 14. The shape of the joining portion at that time can be a combination of angle blades such as a vertical or saw blade, and both ends of the polishing cloth 12 may be overlapped.

  Further, the support member 14 that supports the polishing cloth 12 may not be a flexible material that is deformed by being pressed against the peripheral side surface 36 of the wafer 30 as in the polishing cloth 12, or at least of the outer surface thereof. You may form from the material which has a predetermined | prescribed softness | flexibility which deform | transforms with the abrasive cloth 12 over a predetermined | prescribed thickness. Examples of such materials include urethane, silicon, velukurin, soft PVC, hard resin and metal that are processed into a mesh shape or combined into a thin rod shape, etc., and materials that have flexibility due to deformation due to stress. be able to. In this case, it is preferable that the polishing member 10 (polishing cloth 12) has flexibility (deformable flexibility) as shown in FIG. That is, when the wafer 30 is pressed against the polishing member, the position of the polishing member that is deformed by the end face of the wafer 30 (the most pressed position) is pulled by P1, the polishing member being pressed by the wafer 30. When the position of the deformed polishing member (bending position deformed from the flat surface) is P2, and the radii of curvature at the respective positions are R1 and R2, respectively, as shown in FIG. In this case, R1 ≧ R2, and as shown in FIG. 7 (b), it is preferable to have such flexibility that R1 ≦ R2 when pressed with a strong force.

  Further, the polishing member 10 of the present embodiment is movable so that its polishing position with respect to the wafer 30 can be changed. Such a moving mechanism is provided in the housing 70 as described above. Specifically, the polishing member 10 can make the level of wear of the polishing material uniform throughout the polishing member 10, so that the polishing member 10 can be used evenly (using a wide range of the polishing cloth 12 to polish the polishing member 10. In order to use the cloth 12 efficiently and effectively, for example, the direction perpendicular to the front surface 32 and the back surface 34 of the wafer 30 (that is, the direction along the peripheral side surface 36 of the wafer 30), in this embodiment, the polishing member 10 Can be moved in the longitudinal direction (vertical direction in FIG. 3B). In particular, the polishing member 10 of the present embodiment has a long polishing surface extending in the longitudinal direction so that the wafer 30 can be polished at an arbitrary position along the longitudinal direction (the polishing member 10 is formed long in the longitudinal direction). The height dimension (larger than the thickness dimension of the wafer 30) is set larger than at least the radial dimension.

  In addition, the polishing member 10 of the present embodiment is configured so that the rotation axis O is set to a predetermined angle range (θ) with respect to the vertical axis V as shown in FIG. It can be tilted (can tilt) inside. In this case, the polishing member 10 is polished while rotating around the wafer while the wafer is in a fixed state. However, the polishing member 10 is only required to be in a relatively rotatable relationship. It may be a structure that rotates or both of them rotate. That is, the polishing member only needs to rotate in contact with the peripheral side surface of the wafer, and includes one in which the other rotates with respect to the other and one in which both rotate.

Next, the operation of polishing the wafer 30 by the apparatus 1 having the above configuration will be briefly described with reference to FIGS.
First, a wafer 30 to be polished is carried into the apparatus 1 manually by an operator or automatically by a transfer robot. For example, a cassette containing a plurality of wafers 30 is set in the aforementioned loader unit in the apparatus 1.

  Subsequently, in an automatic apparatus having a transfer robot, the transfer robot takes out one wafer 30 from the cassette of the loader unit, carries it into the polishing unit 5 and places it on the support 2. At this time, the polishing member 10 is retracted to a predetermined standby position by a moving mechanism such as the air cylinder described above, for example, so that the wafer 30 can be carried into the circular support region surrounded by the support 2 without any obstacles.

  When the wafer 30 is loaded into the circular support region surrounded by the support 2 and the wafer 30 is sucked and supported on the support 2, the polishing member 10 is subsequently moved to a predetermined polishing position. At this time, as shown in FIG. 4, the polishing member 10 is pressed against the peripheral side surface 36 of the wafer 30 supported on the support 2 by the urging force of the urging mechanism described above, so that the wafer The peripheral end side surface 30 of 30 is deformed so as to bite into the polishing member 10 (in this embodiment, both the polishing cloth 12 and the support member 14 are deformed), and the biting pressure state is set. Therefore, in this embodiment, the holding force (supporting force) of the wafer 30 by the support 2 is set to be larger than the pressing pressure of the polishing member 10 by the urging force.

  The amount of biting of the polishing member 10 with respect to the peripheral end side surface 36 of the wafer 30 is preferably set to 30% or less with respect to the thickness of the polishing pad 12, including deformation during the pressing operation. Further, in this biting press state, the deforming portion 12A of the polishing pad 12 is opposed to the peripheral end side surface 36 of the wafer 30 and pressed in parallel therewith, and the peripheral end side surface 36 of the wafer 30. The second pressing portion 12b that is obliquely deformed across the front surface 32 and the third pressing portion 12c that is obliquely deformed across the peripheral end side surface 36 to the back surface 34 of the wafer 30 are provided. That is, the polishing cloth 12 turns around from the peripheral side surface 36 of the wafer 30 to the front surface 32 and the back surface 34 due to the deformation.

  Then, in this bite-pressed state, the polishing member 10 is rotated at a predetermined rotational speed by a motor, and the peripheral end side surface of the wafer 30 that comes into contact with the pressing portions 12a, 12b, 12c of the deformed portion 12A of the polishing pad 12 The whole 36 and a part of the front surface 32 and the back surface 34 are polished simultaneously. Further, at the time of such polishing, water, a chemical solution, a polishing solution, and the like are sprayed onto the polishing region by a spray nozzle (not shown) at a predetermined timing. Such polishing is performed, for example, in the range of 5 mm or less of the outer periphery of the wafer 30, and the relative rotational difference between the wafer 30 and the polishing pad 12 is preferably constant.

As described above, the thickness direction of the peripheral edge side surface of the wafer 30 can be polished from the front side to the main surface on the back side by polishing in the state where the polishing member 10 is biting and pressed. By forming the relationship regarding the processing conditions between the peripheral edge side surface of the wafer and the portion reaching the main surface (front and back) as follows, a smoother curved surface is formed from the front side to the main surface on the back side. It is possible.

  In this case, when the polishing cloth is pushed by the wafer, the part reaching the main surface becomes easy to become familiar, and if the part having flexibility (such as non-woven fabric) is hard, the relationship is as shown in the above table. It is also possible to reverse the relationship with the above table by softening the part that has it. In addition, when polishing the peripheral side surface, it is preferable to polish at least one surface (including the entire surface or a part of the surface) of the main surface along with the polishing. A mode in which at least one surface is polished before or after polishing, or at least one surface of the main surface is polished simultaneously with polishing of the peripheral side surface is included.

According to the polishing method of the present embodiment, the following effects can be obtained as compared with the conventional polishing method.
Conventional polishing uses a polishing member and slurry (polishing liquid). When the pressing pressure is increased or the polishing speed is increased, the amount of heat generated is large, and the temperature of the wafer and slurry rises. Supply while managing. For this reason, it is preferable not to use slurry because contamination of the apparatus, supply path / polishing tank / cleaning tank due to slurry, cost due to waste liquid treatment, and environmental problems occur.

  On the other hand, for example, when polishing the wafer by rotating one or both of the wafers using the polishing member 10 with the polishing cloth 12 bonded to the support member 14, the polishing material (polishing) As shown in FIG. 6, the abrasive grains 17 are deposited on a flexible portion and are attached to a soft portion (protrusion) such as a nonwoven fabric or a woven fabric. And there is a margin of movement in the positional relationship of the accumulated abrasive material, and the abrasive material on the polishing cloth is unstablely vibrated minutely.

  This makes it possible to create a more random (non-uniform) polishing state compared to a polishing method in which the polishing member only rotates, and polishing unevenness is eliminated by stacking random polishing, resulting in better polishing. An effect is obtained. Further, this unstable minute vibration is close to the effect of polishing using a slurry (polishing liquid = free abrasive grains), and a good polishing result can be obtained even when no slurry is used. In other words, if no slurry is used, only water temperature control is required, so there is no contamination of the polishing apparatus, wafer (object to be polished), slurry supply path, cleaning tank, polishing tank, etc., and no waste liquid treatment is required. Maintenance, materials used, waste liquid treatment costs can be reduced, and environment-friendly polishing can be performed.

  An example of the polished state obtained by the polishing process as described above is shown in FIG. 5A is polished in a state where the polishing member 10 is oriented in the vertical direction along the vertical axis V (see FIG. 3) as shown in FIG. 3B and FIG. The polishing state of the peripheral end side surface 36, the front surface 32, and the back surface 34 of the wafer 30 is shown. As shown in the figure, in this polishing state, polishing is performed by the flat first polishing region 36a polished by the first pressing portion 12a of the deforming portion 12A of the polishing cloth 12 and the second pressing portion 12b of the polishing cloth 12. The second polishing region 36b smoothly connected to the first polishing region 36a without the edge and curved and the third pressing portion 12c of the polishing pad 12 is polished without the edge. A first polishing region 36a and a third polishing region 36c that is smoothly connected and curved are formed.

  On the other hand, in FIG. 5B, the polishing was performed in a state where the polishing member 10 was inclined by a predetermined angle θ with respect to the vertical axis V (see FIG. 3) as shown in FIG. 3C. The polishing state of the peripheral end side surface 36, the front surface 32, and the back surface 34 of the wafer 30 is shown. As shown in the figure, in this polishing state, a first polishing region 36a ′ that is polished by the first pressing portion 12a of the polishing pad 12 and that is inclined so as to form an angle θ with respect to the vertical axis V, and polishing. A second polishing region 36b 'that is polished and smoothly connected to the first polishing region 36a' without an edge and is polished by the second pressing portion 12b of the cloth 12, and a third pressing of the polishing cloth 12 The first polishing region 36a ′ and the third polishing region 36c ′ that are smoothly connected and curved without an edge are polished by the portion 12c.

  When the polishing process is completed as described above, the polished wafer 30 may be subsequently transferred to the above-described cleaning unit by the transfer robot. It is also possible to perform cleaning using the polishing member 10. Specifically, the above-described biting and pressing state during the polishing process is released, and the polishing member 10 is lightly brought into contact with the peripheral end side surface 36a (36a ') of the polished wafer 30. In this state, the polishing member 10 is rotated again to clean the polishing region. At this time, a cleaning liquid (for example, an alkaline cleaning liquid) containing water, a chemical liquid, or the like is sprayed from a spray nozzle (not shown) toward the cleaning region. If necessary, cleaning is performed using a brush, high-pressure spray, detergent, or the like. At this time, the polishing member 10 may also be cleaned together with the wafer or separately from the wafer by spraying the cleaning liquid.

  When such cleaning is completed, the cleaned wafer 30 is then transferred to the drying unit described above. Alternatively, the drying step is continued without being transported as it is in a cleaning tank, a polishing tank or the like (position where polishing is performed). At this time, the polishing member 10 of the polishing processing unit 5 is moved in the longitudinal direction before the next wafer is fed, and the polishing position is changed. The drying in the drying unit is performed, for example, by spraying a dry gas on the wafer 30 rotated by the turntable. After the drying is completed, the wafer 30 is unloaded to the unloader unit by the transfer robot and stored in the original cassette.

  As described above, in the apparatus 1 according to the present embodiment, the polishing member 10 polishes the peripheral end side surface 36 in a state in which the polishing member 10 is deformed by being pressed against the peripheral end side surface 36 of the wafer 30 by the biasing force of the biasing mechanism. The wafer 30 can be smoothly polished from the peripheral end side surface 36 to the front surface 32 and the back surface 34 without causing an edge at the boundary between the peripheral end side surface 36 and the front surface 32 and the back surface 34 of the wafer 30. This is also due to the fact that the polishing cloth 12 of the polishing member 10 can wrap around from the peripheral side surface 36 of the wafer 30 to the front surface 32 and the back surface 34 as described above. In addition, if the wafer 30 can be smoothly polished from the peripheral side surface 36 to the front surface 32 and the back surface 34 and no edge is generated on the wafer, adhesion of foreign matters can be avoided. Further, such deformation of the polishing member 10 (polishing cloth 12) during polishing processing is a setting failure including a deviation from a predetermined processing position of the wafer 30 regardless of the processing mode such as batch type or single wafer type. Even in the case where there is such a defect, such a defect factor is absorbed, and smooth polishing from the peripheral end side surface 36 of the wafer 30 to the front surface 32 and the back surface 34 is enabled. In this case, the polishing member 10 may move in a stopped state when contacting or leaving the wafer, but it is preferable to reduce the polishing mark when starting to rotate by moving while rotating. Therefore, not only the manual process but also the polishing process can be automated, which can contribute to the improvement of the yield.

  Further, since the polishing member 10 is pressed against the peripheral end side surface 36 of the wafer 30 by the urging force of the urging mechanism, the polishing member 10 follows the contour of the outer periphery of the wafer 30 even when the wafer 30 has an orientation flat. By moving in the radial direction, the peripheral end side surface 36 can always be contacted with a desired pressure over the entire circumference of the wafer 30 including the orientation flat. That is, according to the present embodiment, the wafer 30 can be smoothly polished over the entire circumference from the peripheral side surface 38 to the front surface 32 and the back surface 34 regardless of the shape thereof.

  Further, according to the above-described polishing member, in the side surface polishing and the surface polishing, the portion having flexibility disperses the pressure more than necessary and the polishing follows the surface. In this case, if it is a non-deformable polishing member, mechanical accuracy and rigidity are required, but by using a deformable polishing member as described above, these can be absorbed, and mechanical It becomes possible to reduce the level of accuracy and rigidity. Further, the above-described polishing member can be deformed and can be polished at any position of the wafer, and the biasing force can be adjusted at the same time, so that the wafer is polished in units of one sheet, or in units of a plurality or multiple sheets. You can also. In this case, by adjusting (or automatically controlling) the position and urging force of the polishing member during continuous operation, it is possible to perform polishing without stopping the operation.

  In this embodiment, since the polishing cloth 12 is detachably attached to the support member 14 (replaceable), only the polishing cloth 12 needs to be replaced when the abrasive is consumed. Processing costs (and thus manufacturing costs) can be reduced. Further, in this embodiment, not only the polishing cloth 12 but also at least the outer surface of the support member 14 can be deformed by the biasing force over a predetermined thickness, so that the deformation amount of the polishing member 10 is the thickness of the polishing cloth 12. However, the desired deformation of the polishing member 10 can be realized by the combination of the polishing cloth 12 and the support member 14, and a good polishing process can always be performed.

  Furthermore, in this embodiment, the positional relationship between the polishing member and the wafer has a movable mechanism, and the position can be moved as necessary in addition to the rotation. Therefore, the polishing cloth and the polishing process are overlapped. Can be polished evenly. In this case, since the polishing member 10 is movable so that its polishing position with respect to the wafer 30 can be changed, by changing the polishing position for each polishing process, the degree of consumption of the abrasive is made uniform over the entire polishing member 10. Therefore, the polishing member 10 can be used evenly (the polishing cloth 12 can be used efficiently and effectively by utilizing a wide range of the polishing cloth 12). In the present embodiment, since the polishing member 10 can tilt, smooth polishing from the peripheral end side surface 36 of the wafer 30 to the front surface 32 and the back surface 34 is further facilitated.

  The above-mentioned polishing member (polishing cloth) may be made of a material that allows water to penetrate. In that case, a heat dissipation effect for the polishing heat can be obtained, and by controlling the temperature of the supplied water, It is also possible to manage the temperature of Thereby, the thermal expansion due to the temperature rise of the wafer or the like is suppressed, and a good polishing result can be obtained.

  In addition, the abrasive cloth is not limited to cloth such as the above-mentioned nonwoven fabric or woven cloth, for example, a sheet form including a product made by compressing a piece of material, a cloth form, an abrasive, It is also possible to use a material in which abrasives, particles, and the like are exposed and adhered to the surface of a member that is integrated by kneading particles, a support member, and the like.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to embodiment mentioned above, A various deformation | transformation implementation is possible in the range which does not deviate from the summary. For example, in the embodiment described above, the number of polishing members 10 is four, but the number of polishing members 10 can be arbitrarily set. In the above-described embodiment, the present apparatus is disclosed as a single wafer processing apparatus. However, the present invention can also be applied to batch processing.

  Further, in the above embodiment, the polishing member is configured in a roll shape (columnar shape) as shown on the right side of FIG. 8, but is configured in a disc shape (disc shape) as shown on the left side thereof. It may be what was done. For example, as shown in FIG. 9A, such a disk-shaped polishing member 110 has a disk-shaped polishing cloth 112 configured as described above on one surface of a disk-shaped support member 114. And a mounting portion 118 of a rotating mechanism such as a motor may be provided on the other surface. In this case, as illustrated in FIGS. 9B and 9C, the polishing pad 112 may have a small diameter or a large diameter with respect to the attachment portion 118.

  As for the polishing member at the time of polishing the wafer, for example, as shown in FIG. 10 (a), a plurality of polishing cloths 112 are in contact with the wafer 30 for polishing, as shown in FIG. 10 (b), A polishing cloth 112A larger than the diameter of the wafer 30 is in contact with the wafer for polishing. As shown in FIG. 10C, a plurality of polishing cloths 112B having a diameter smaller than the diameter of the wafer 30 are provided. It may be one that contacts and polishes 30 while changing its position.

  In the above-described embodiment, the polishing member has a structure (composite structure) in which the polishing cloth 12 as another member is attached to the surface of the columnar support member 14 as shown in FIG. However, the polishing member may have a single structure. For example, you may comprise with the abrasive | polishing member etc. which have the elasticity with which the abrasives were mixed with the surface of the raw material which can be elastically deformed, such as urethane.

DESCRIPTION OF SYMBOLS 1 Apparatus 2 Support body 10,110 Polishing member 12,112,112A, 112B Polishing cloth 14 Support member 30 Wafer (working material)
32, 34 Main surface 36 Peripheral end side surface 76 Spring (biasing mechanism)

Claims (10)

A polishing member that polishes the peripheral end side surface and / or main surface by rotating in contact with the peripheral end side surface and / or main surface of the workpiece,
The polishing member has a flexible polishing cloth, and a granular abrasive is supported on the surface of the polishing cloth.   The polishing cloth is composed of a woven or non-woven cloth having a surface with feathers or a flock-like protrusion formed thereon, and the abrasive is attached to and / or bited into the feathering part or protrusion. The polishing member according to claim 1.   The abrasive member according to claim 2, wherein the abrasive is deposited in a layered manner on the surface of the woven fabric or nonwoven fabric.   The said polishing cloth is attached to the outer periphery of the support member which can rotate, and can deform | transform by press-contacting with the said to-be-processed raw material, The any one of Claim 1 to 3 characterized by the above-mentioned. Polishing member. A polishing member for polishing the peripheral side surface by rotating in contact with the peripheral side surface of the workpiece,
It has a rotatable support member and an abrasive cloth that is attached to the outer periphery of the support member and carries an abrasive on the surface, and the abrasive cloth is deformable by being in pressure contact with the workpiece. An abrasive member.   A polishing method comprising polishing the work material by using the polishing member according to any one of claims 1 to 5 and pressing the polishing cloth against the work material to deform the work cloth. Support the work material so that it can rotate while its position is regulated by the support,
A biting press that deforms the polishing member such that the polishing member is pressed and brought into contact with the peripheral end side surface of the workpiece material supported by the support so that the peripheral end side surface of the workpiece material bites into the polishing member. State
Polishing the peripheral side surface of the workpiece by rotating the polishing member in the biting press state,
A polishing method characterized by the above.   The polishing method according to claim 7, wherein the biting press state is released, and the peripheral end side surface of the workpiece is further cleaned by the polishing member.   The polishing method according to claim 8, wherein the polishing member is cleaned with a cleaning liquid.   The polishing method according to claim 7, wherein at least one main surface of the workpiece material is polished together with the peripheral side surface of the workpiece material.

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