JP6848636B2 - Substrate peripheral cleaning device, substrate peripheral cleaning method and storage medium - Google Patents

Description

The present invention relates to a technique for cleaning the peripheral edge of a substrate using a polishing tape.

In the semiconductor device manufacturing process, a semiconductor wafer (hereinafter referred to as a wafer), which is a substrate, is conveyed between various devices by a conveying mechanism, and a series of processes including a film forming process and an etching process are performed. .. In the process of performing such a series of processes, an unnecessary film may remain on the peripheral edge of the wafer or a foreign substance may adhere to the wafer. In that case, there is a risk of adversely affecting the processing of the wafer in the transfer destination device, or when the transfer mechanism comes into contact with the peripheral edge of the wafer, the above-mentioned unnecessary film or foreign matter becomes particles and falls from the wafer to contaminate the device. There is a risk that it will end up.

Patent Documents 1 and 2 describe a device that performs cleaning by pressing the polishing tape against the peripheral edge of the wafer by a polishing head provided with one holding portion for holding the polishing tape and rotating the wafer. There is. The polishing head is configured so that its orientation can be freely changed around the horizontal axis so that each surface constituting the peripheral edge of the wafer and having different inclinations can be polished, and the holding portions are formed from different directions. Press the polishing tape against the wafer. However, in the apparatus configuration for changing the orientation of the polishing head having one holding portion as described above, in order to clean all the surfaces constituting the peripheral portion of the wafer, the polishing head is tilted at a predetermined position for each surface. It takes a lot of time to process because it needs to be placed in

Japanese Unexamined Patent Publication No. 2012-213849 Japanese Unexamined Patent Publication No. 2012-231191

The present invention has been made under such circumstances, and an object of the present invention is to provide a technique capable of reducing the time required for processing when cleaning the peripheral edge of a substrate using an abrasive tape. ..

The substrate peripheral portion cleaning device of the present invention includes a substrate holding portion that holds the substrate and a substrate holding portion.
A rotation mechanism for rotating the substrate held by the substrate holding portion, and
A polishing head including a first tape holding portion that holds the polishing tape on the side of the substrate and a second tape holding portion that holds the polishing tape below the substrate.
With a forward mechanism that advances the substrate holding portion relative to the polishing head so that the side surface of the rotating substrate slides on the polishing tape held by the first tape holding portion and is cleaned. ,
An ascending mechanism that raises the polishing head relative to the substrate so that the lower surface of the rotating peripheral edge of the substrate is slid and cleaned by the polishing tape held by the second tape holding portion. When,
It is characterized by having.

The method for cleaning the peripheral portion of the substrate of the present invention includes a step of holding the substrate by the substrate holding portion and a step of holding the substrate.
The step of rotating the substrate held by the substrate holding portion and
A step of holding the polishing tape on the side of the substrate and below the substrate by the first tape holding portion and the second tape holding portion constituting the polishing head, respectively.
A step of advancing the substrate holding portion relative to the polishing head so that the side surface of the rotating substrate slides on the polishing tape held by the first tape holding portion and is cleaned.
A step of raising the polishing head relative to the substrate so that the lower surface of the rotating peripheral edge of the substrate is slid and cleaned by the polishing tape held by the second tape holding portion. ,
It is characterized by including.

In a storage medium that stores a computer program used in a cleaning device that slides the peripheral edge of a substrate onto a polishing tape for cleaning.
The computer program is characterized in that a group of steps is set up to execute the above-mentioned cleaning method of the peripheral portion of the substrate.

In the present invention, a polishing head including a first tape holding portion for holding the polishing tape on the side of the substrate and a second tape holding portion for holding the polishing tape below the substrate is provided. Then, the relative advancement of the rotating substrate with respect to the polishing head and the relative elevation of the polishing head with respect to the rotating substrate are performed to clean the peripheral edge of the substrate. Since the first tape holding portion and the second tape holding portion can clean the surfaces in different directions on the peripheral edge of the substrate, the polishing head is adjusted to each surface constituting the peripheral edge of the substrate. Since the time for arranging can be suppressed, the time required for processing can be suppressed.

It is a perspective view of the cleaning apparatus of the peripheral part of a substrate which concerns on this invention. It is a top view of the cleaning device. It is a longitudinal side view of a wafer. It is a perspective view which shows the polishing head provided in the cleaning apparatus, and the tape mounting mechanism. It is a vertical sectional side view which shows the polishing head provided in the cleaning apparatus, and the tape mounting mechanism. It is a perspective view of the head body which constitutes the polishing head. It is a vertical sectional side view of the air supply / exhaust mechanism provided in the cleaning device. It is explanatory drawing which shows the procedure of attaching a polishing tape to the head body. It is explanatory drawing which shows the procedure of attaching a polishing tape to the head body. It is explanatory drawing which shows the procedure of attaching a polishing tape to the head body. It is explanatory drawing which shows the procedure of attaching a polishing tape to the head body. It is a perspective view of the head body to which the polishing tape is attached. It is a perspective view of the head body to which the polishing tape is attached. It is explanatory drawing which shows the procedure of a cleaning process. It is explanatory drawing which shows the procedure of a cleaning process. It is explanatory drawing which shows the procedure of a cleaning process. It is a front view of the processing pad provided in the head body. It is a front view of the processing pad provided in the head body. It is a front view of the processing pad provided in the head body. It is a top view of the processing pad. It is a schematic front view which shows the other polishing head.

The cleaning device 1 for the peripheral portion of the substrate, which is an embodiment of the present invention, will be described with reference to the perspective view of FIG. 1 and the plan view of FIG. The cleaning device 1 performs a cleaning process for removing unnecessary films and foreign substances on the peripheral edge of the wafer W, which is a circular substrate having a diameter of 300 mm, by sliding the peripheral edge of the wafer W with respect to the polishing tape. ..

FIG. 3 is a vertical sectional side view showing the peripheral edge of the wafer W. The side end faces forming the side circumference of the wafer W are continuously formed on the side end faces 11, and the upper inclined surface that rises from the side end faces 11 toward the center of the wafer W is continuously formed on the side end faces 11. , The lower inclined surface that descends from the side end surface 11 toward the center of the wafer W is shown as 13. The side end surface 11, the upper inclined surface 12, and the lower inclined surface 13 form the side surface of the wafer W. The upper inclined surface 12 and the lower inclined surface 13 are continuous with the front surface (upper surface) and the back surface (lower surface) of the horizontal wafer W, respectively. The back surface peripheral region leading to a position away from the center is shown as 14. The cleaning device 1 cleans a continuous region from the upper end of the upper inclined surface 12 to the back surface peripheral region 14 surrounded by a dotted frame in FIG.

Returning to FIGS. 1 and 2, the description of the cleaning device 1 will be continued. 21 in the figure is a base, and 22 in the figure is a slit formed on the base 21 so that its length direction is along the front-rear direction. Reference numeral 23 in the drawing is a rotation mechanism provided so as to project from the inside of the slit 22 onto the base 21, and is moved in the front-rear direction by the front-back movement mechanism 24 provided in the base 21. The front-back movement mechanism 24 is a forward-moving mechanism that advances the wafer W with respect to the polishing head 3 described later. Reference numeral 25 denotes a spin chuck forming a substrate holding portion, which is provided on the rotating mechanism 23 and attracts the central portion of the back surface of the wafer W to horizontally support the wafer W. The spin chuck 25 is rotated around the vertical axis by the rotation mechanism 23, so that the wafer W mounted on the spin chuck 25 rotates around the central axis of the wafer W. The spin chuck 25 is located at a retracted position for delivering the wafer W to and from a transport mechanism provided outside the cleaning device 1 in FIG. 1, and a forward position for processing the wafer W in FIG. It shows the state located in each.

On the base 21, a left-right movement mechanism 26, an elevating mechanism 27, and a polishing head 3 are provided in front of the moving path of the spin chuck 25. The elevating mechanism 27 moves horizontally on the base 21 by the left-right moving mechanism 26, and the polishing head 3 moves vertically by the elevating mechanism 27. That is, the polishing head 3 moves horizontally to the left and right and moves up and down vertically by the left-right movement mechanism 26 and the elevating mechanism 27. Therefore, the elevating mechanism 27 forms an elevating mechanism that elevates the polishing head 3 relative to the wafer W.

The polishing head 3 will be described with reference to FIG. 4 which is a perspective view and FIG. 5 which is a longitudinal side view. The polishing head 3 includes a plate-shaped support portion 31 that is vertical and extends in the front-rear direction, and the support portion 31 is connected to the elevating mechanism 27. In this support portion 31, a tape sending reel 32, a tape collecting reel 33, and a head body 4 are provided on the left side surface when viewed forward, and a motor 34 and a rotation limiting portion are provided on the right side surface. 35 is provided. The head main body 4 is provided at the rear end portion of the support portion 31, and holds the polishing tape T for cleaning. The tape sending reel 32 and the tape collecting reel 33 are provided on the front side of the head body 4 so that they can rotate about the horizontal axis along the left-right direction, respectively, and the tape sending reel 32 is provided from the tape collecting reel 33. Is also located above and in front.

A roll T1 of an unused polishing tape T is attached to the tape delivery reel 32, and the roll T1 rotates together with the tape delivery reel 32. The end portion of the polishing tape T drawn out from the roll T1 in the length direction passes through the rear side of the head body 4 and is wound around the tape recovery reel 33 to form the roll T2, and the roll T2 is a tape. It rotates with the recovery reel 33. Therefore, rotating the tape recovery reel 33 pulls the end portion of the polishing tape T in the length direction, and by rotating the tape recovery reel 33 in this way, the polishing tape T has been used in the head body 4. Can be wound around the tape recovery reel 33 and removed from the head body 4, and an unused area of the polishing tape T can be sent from the roll T1 of the tape delivery reel 32 to the head body 4. In addition, in FIG. 1, FIG. 2, and FIG. 4, the illustration of the polishing tape T between the rolls T1 and T2 is omitted.

The motor 34 rotates the tape recovery reel 33 as described above. The rotation limiting unit 35 is designed so that the tape delivery reel 32 rotates only when a load equal to or higher than a set value is applied to the tape delivery reel 32 by pulling the polishing tape T pulled out from the roll T1. The rotation of the delivery reel 32 is restricted. When a load greater than or equal to this set value is applied, the unused region of the polishing tape T is supplied to the head body 4 by the rotation of the motor 34, and the unused region is supplied to the tape mounting mechanism 6 as described later. It is time to attach it to the head body 4. The tape feeding reel 32, the tape collecting reel 33, the motor 34, and the rotation limiting portion 35 described above constitute a tape feeding mechanism that moves a region of the polishing tape T located on the head body 4 in the length direction.

Subsequently, the head main body 4 will be described. The head main body 4 includes an upright wall portion 41 and a base portion 42 that discharges from the lower end of the wall portion 41 to the rear side. A central portion in the left-right direction at the upper end portion of the wall portion 41 is cut out, and a roller 43 is provided in the notched central portion. The rear end portion of the base portion 42 is stretched downward, and the central portion in the left-right direction is cut out, and the rollers 44 and 45 are provided in two upper and lower stages in the cutout central portion. There is. The rollers 43 to 45 are configured so that they can rotate with the left and right horizontal axes as rotation axes. As shown in FIG. 5, the polishing tape T is hung on these rollers 43 to 45 between the rolls T1 and T2, and is drawn in the vertical direction when viewed from the front. The rollers 43 and 44 are above the side processing pad 54 and the side suction pad 55 forming the first tape holding portion, which will be described later, and the lower processing pad 51 and the lower suction pad 52 forming the second tape holding portion. Above, the polishing tape T is configured as a suspension portion for suspending the polishing tape T, and the upper surface of the polishing tape T suspended between the rollers 43 and 44 is a polishing surface (surface) on which the polishing material is provided.

The upper surface of the pedestal 42 is formed horizontally, and elongated rectangular lower processing pads 51 are provided on the left and right so as to project upward from the upper surface of the pedestal 42. The lower processing pad 51 is a substrate pressing portion to which the wafer W is pressed via the polishing tape T, and is made of an elastic body such as silicone, and its upper surface is formed horizontally. The upper surface of the lower processing pad 51 forms a contact surface to which the polishing tape T is adhered.

Further, the base portion 42 is formed in a U shape so as to surround the lower treatment pad 51 from three sides of the left side, the right side, and the rear side, and the lower suction pad 52 made of a porous material such as ceramics is formed. Is provided so as to slightly project upward from the surface of the base portion 42. The upper surface of the lower suction pad 52 is formed horizontally, and is provided at a position lower than the upper surface of the lower treatment pad 51 when viewed from the upper surface of the lower treatment pad 51. The lower treatment pad 51 and the lower suction pad 52 are formed in a symmetrical layout, and when viewed in a plane, they overlap the polishing tape T hung on the rollers 43 to 45, and the lower treatment pad 51 and the lower suction pad 52 are suctioned. The left and right centers of the pad 52 are aligned with the left and right centers of the polishing tape T.

The lower suction pad 52 is connected to an exhaust mechanism (not shown). By being exhausted from the hole on the upper surface of the lower suction pad 52 by this exhaust mechanism, the polishing tape T pressed against the lower suction pad 52 is sucked as described later, whereby the polishing tape T is lowered. It is held in close contact with the side processing pad 51. Therefore, the lower suction pad 52 forms a tape suction portion, the upper surface of the lower suction pad 52 is a suction surface, and the holes on the upper surface form suction holes. The exhaust mechanism switches between a state in which suction is performed from the lower suction pad 52 and a state in which suction is not performed.

Further, two suction holes 53 are opened on the upper surface of the base portion 42 so as to sandwich the lower processing pad 51 and the lower suction pad 52 from the left and right, and these suction holes 53 are viewed in a plane. The base portion 42 is provided outside the region where the polishing tape T is held. The suction hole 53 is connected to an exhaust mechanism (not shown), and the state in which suction is performed by the exhaust mechanism and the state in which suction is not performed can be switched. During the cleaning process, suction is performed, and the shavings generated in the cleaning process are sucked and removed.

The front surface of the wall portion 41 facing rearward is formed along the left-right direction and the vertical direction, and the front surface is provided with elongated rectangular side treatment pads 54 on the left and right so as to project rearward. There is. The vertical length of the side processing pad 54 is longer than the front and rear length of the lower processing pad 51, but the side processing pad 54 is the same as the lower processing pad 51 except for such a difference in length. It is configured. Therefore, the side processing pad 54 also forms a substrate pressing portion to which the wafer W is pressed via the polishing tape T, and the front surface thereof forms a contact surface to which the polishing tape T is adhered. The lower end of the side processing pad 54 is positioned at a height lower than the upper surface of the lower processing pad 51.

Further, on the front surface of the wall portion 41, a side suction pad 55 formed in a U shape so as to surround the side treatment pad 54 from three sides of the left side, the right side and the upper side is slightly rearward from the front surface of the wall portion 41. It is provided so as to protrude. The side processing pad 54 protrudes more from the front surface of the wall portion 41 than the side suction pad 55. Therefore, when viewed from the front of the side processing pad 54, the front surface of the side suction pad 55 is provided at a position lower than the front surface of the side processing pad 54. Further, the front surface of the side suction pad 55 forms a vertical surface. The side suction pad 55 is configured in the same manner as the lower suction pad 52, and is connected to an exhaust mechanism (not shown), and suction is performed from the hole in front of the exhaust mechanism, and the suction is performed. You can switch between the untouched state. Therefore, the side suction pad 55 is also configured as a tape suction portion, and the front surface of the side suction pad 55 forms a suction surface, and the hole in the front surface forms a suction hole.

The side treatment pad 54 and the side suction pad 55 are formed in a symmetrical layout, and overlap with the polishing tape T hung on the rollers 43 to 45 when viewed forward, and the side treatment pad 54 The left and right centers of the side suction pad 55 and the side suction pad 55 are aligned with the left and right centers of the polishing tape T. The side suction pad 55 sucks the polishing tape T pressed against the side suction pad 55 as described later, whereby the polishing tape T is held in close contact with the side treatment pad 54.

To show an example of the dimensions of each part with reference to FIG. 6 in which the wall portion 41 and the base portion 42 are enlarged, the left and right width L1 of the lower processing pad 51 is 34 mm, and the lower processing pad 51 has a width L1 of 34 mm. The width L2 before and after 51 is 9 mm. The left and right width L1 is also the left and right width of the side processing pad 54. For the lower suction pad 52, the front-rear width L3 is 17 mm, and the left-right width L4 is 47 mm. This width L4 is slightly smaller than the width of the polishing tape T. Further, the left and right width L5 of the edge of the region surrounded by the lower suction pad 52 is 39 mm. Since the lower suction pad 52 and the side suction pad 55 are configured in the same manner as described above, the dimensions of each part of the lower suction pad 52 shown above are the dimensions of each part of the side suction pad 55. It is also a dimension. Further, the height difference H1 between the upper surface of the lower processing pad 51 and the upper surface of the lower suction pad 52 is 2.5 mm, and the front and back of the front surface of the side treatment pad 54 and the front surface of the side suction pad 55. The distance L6 is also 2.5 mm.

Subsequently, returning to FIGS. 1 and 2, the tape mounting mechanism 6 provided in the cleaning device 1 will be described. The tape mounting mechanism 6 presses the polishing tape T suspended on the rollers 43 and 44 toward the lower processing pad 51 and the lower suction pad 52 to bring them into close contact with the pads 51 and 52. , It forms a pressing mechanism that presses toward the side processing pad 54 and the side suction pad 55 to bring them into close contact with the pads 54 and 55. The tape mounting mechanism 6 includes a front-rear moving mechanism 61, a rolling element support portion 62, and a tape mounting roller 63.

On the base 21, a slit 28 (omitted in FIG. 2) extending in the front-rear direction is formed on the rear side of the position where the head main body 4 is provided. A rolling element support portion 62 is provided so as to extend from the inside of the slit 28 onto the base 21, and the rolling element support portion 62 is connected to a front-rear moving mechanism 61 provided in the base 21. The front-back movement mechanism 61 moves back and forth. Further, on the base 21, the upper portion of the rolling element support portion 62 extends forward and then is bent so as to extend in the horizontal direction, and the portion extending in the horizontal direction is directed forward from a position separated from the left and right. Each projecting portion is formed, and a tape mounting roller 63 is provided between the projecting portions. Therefore, the front-rear movement mechanism 61 allows the tape mounting roller 63 to move in the front-rear direction via the rolling element support portion 62.

FIG. 4 shows a perspective view of the tape mounting roller 63, and FIG. 5 shows a longitudinal side view of the tape mounting roller 63. The tape mounting roller 63 is configured to be rotatable around a horizontal axis extending to the left and right. The left and right edges of the tape mounting roller 63 are each expanded in diameter to form a large diameter portion 64, and a small diameter portion 65 is formed between the large diameter portions 64. Therefore, the rotation axis of the large diameter portion 64 and the rotation axis of the small diameter portion 65 coincide with each other.

As will be described in detail later, by forming the large diameter portion 64 and the small diameter portion 65 in this way, each large diameter portion 64 rolls a portion extending back and forth at each of the left and right ends of the lower suction pad 52. At the same time, the small diameter portion 65 rolls the lower processing pad 51, and each large diameter portion 64 rolls a portion extending back and forth at each of the left and right ends of the side suction pad 55, and the small diameter portion 65 laterally rolls. The polishing tape T can be attached to the head body 4 by rolling the processing pad 54. The size of each diameter of the large diameter portion 64, which is the first rolling element, and the small diameter portion 65, which is the second rolling element, is set so that the rolling can be performed in this way. Except for the case where the polishing tape T is mounted as described above, the tape mounting roller 63 stands by at a standby position behind the polishing head 3. Further, the tape mounting roller 63 and the rolling element support portion 62 are provided below the upper end of the spin chuck 25 so as not to interfere with the wafer W to be cleaned.

Further, as shown in FIGS. 1 and 2, when the base 21 is viewed forward, an air supply / exhaust mechanism 7 is provided on the right side of the head body 4 near the head body 4. .. The air supply / exhaust mechanism 7 will be described with reference to the vertical sectional side view of FIG. The air supply / exhaust mechanism 7 includes a side wall 71, and the side surface 72 constituting the side wall 71 faces the side end surface 11 in a part of the circumference of the wafer W and is formed along the circumference of the wafer W. The upper end and the lower end of the side wall 71 protrude toward the rear side toward the right side when viewed from the front, and form the upper plate 73 and the lower plate 74, respectively. The upper plate 73 and the lower plate 74 are formed horizontally and face each other at a distance from each other, and cover a part of the peripheral edge portion of the wafer W held by the spin chuck 25 located at the forward position. By configuring each portion in this way, the region surrounded by the upper plate 73, the lower plate 74, and the side wall 71 has a flat arc shape, and the peripheral edge portion of the wafer W is housed and the peripheral edge portion of the wafer W is accommodated. It forms a purge space 75 for supplying purge gas.

A plurality of exhaust ports 76 toward the side end surface 11 of the wafer W are opened on the side surface 72 at intervals along the circumferential direction of the purge space 75. Reference numeral 77 in the figure is an exhaust mechanism to which the exhaust port 76 is connected. Further, the upper plate 73 and the lower plate 74 are opened with gas discharge ports 78 and 79 for discharging _{N 2} (nitrogen) gas, which is a purge gas, from the inside to the outside in the radial direction of the wafer W, respectively. The discharge port 78 discharges gas diagonally downward toward the peripheral edge of the front surface of the wafer W, and the gas discharge port 79 discharges gas diagonally upward toward the peripheral edge of the back surface of the wafer W. A plurality of gas discharge ports 78 and 79 are provided at intervals along the circumferential direction of the purge space 75 so that purge gas can be discharged to different positions along the circumferential direction of the wafer W.

Reference numeral 81 in the drawing is a gas flow path provided on the upstream side of each gas discharge port 78 in the upper plate 73. 82 in the figure is a gas flow path provided on the upstream side of each gas discharge port 79 in the lower plate 74. The N2 gas sent from the N2 gas supply source 83 is supplied to each of the gas flow paths 81 and 82, respectively. During the cleaning process of the wafer W, N2 gas is discharged from the gas discharge ports 78 and 79 to the front surface and the back surface of the wafer W and exhausted from the outside of the wafer W by the exhaust port 76 in parallel, and purged. As shown by an arrow in FIG. 7, an air flow from the inside to the outside of the wafer W is formed in the space 75. By being exposed to this air flow, the shavings adhering to the peripheral edge of the wafer W are purged and removed.

Further, as shown in FIGS. 1 and 2, the cleaning device 1 is provided with a control unit 10 which is a computer. The control unit 10 has a program storage unit (not shown). In this program storage unit, a program in which an instruction (step group) is set so that the cleaning process described later and the polishing tape T is attached to the head body 4 is stored is stored. By this program, the control unit 10 outputs a control signal to each unit of the cleaning device 1 to control the operation of each unit. This program is stored in the program storage unit in a state of being stored in a storage medium such as a hard disk, a compact disk, a magnet optical disk, or a memory card.

Subsequently, regarding the operation of mounting the polishing tape T on the head body 4, explanatory views of FIGS. 8 to 11 showing the state of the polishing tape T and the positions of the head body 4 and the tape mounting roller 63, and FIG. 5 above. It will be described using and. Further, the perspective views of FIGS. 12 and 13 showing the positions of the head body 4 and the tape mounting roller 63 are also referred to as appropriate. First, the suction by the lower suction pad 52 and the side suction pad 55 is stopped, and the tape mounting roller 63 stands by at the standby position behind the polishing head 3 at a predetermined height and at a predetermined position on the left and right. The polishing head 3 is located. FIG. 5 shows a state in which the polishing head 3 is arranged at this predetermined position. Further, at this time, the used region of the polishing tape T is wound around the roll T2 in the head body 4 of the polishing head 3, and the unused regions of the polishing tape T are loosened on the rollers 43 and 44 of the head body 4. It is in a suspended state so that it does not exist.

Then, as the tape mounting roller 63 advances from the state shown in FIG. 5, suction by the lower suction pad 52 and the side suction pad 55 is started. The polishing tape T between the rollers 43 and 44 abuts on the large diameter portion 64 of the tape mounting roller 63 and is pressed toward the base portion 42 of the head body 4, and is pressed onto the upper surface of the rear end portion of the lower suction pad 52. The left and right edges of the polishing tape T are pressed against each other, the central portion of the polishing tape T is close to the upper surface of the rear end portion of the lower suction pad 52, and the left and right edges and the central portion thereof are below the polishing tape T. By suction from the side suction pad 52, the lower suction pad 52 is brought into close contact with and fixed (FIG. 8).

Further, the tape mounting roller 63 advances, the large diameter portion 64 rolls on the lower suction pad 52, and the left and right edges of the polishing tape T are pressed forward toward the lower suction pad 52. It adheres to the lower suction pad 52 and is sucked and fixed. After that, the small diameter portion 65 rides on the upper surface of the lower processing pad 51 and rolls on the upper surface, and the left and right central portions of the polishing tape T are pressed against the upper surface of the lower processing pad 51 and adhere to the upper surface. It is laid to do. In the polishing tape T, the left and right sides of the portion laid on the lower treatment pad 51 are fixed to the lower suction pad 52, so that the portion laid on the lower treatment pad 51 is the lower treatment pad. It is fixed in close contact with 51.

When the tape mounting roller 63 continues to move forward and the polishing tape T is laid over the entire upper surface of the lower processing pad 51, the large diameter portion 64 is placed in front of the lower side of the side suction pad 55, and the small diameter portion 65 is placed. The polishing tape T is pressed against the front surfaces of the lower side of the side treatment pads 54, respectively, and the advancing of the tape mounting roller 63 is stopped. The left and right edges of the polishing tape T pressed against the large diameter portion 64 in this way are in close contact with the side suction pad 55, and are sucked and fixed. Further, the left and right central portions of the polishing tape T pressed against the small diameter portion 65 are laid so as to be in close contact with the front surface of the side treatment pad 54, and the left and right edge portions thereof are side suction pads as described above. By being fixed to 55, it is fixed to the side processing pad 54 (FIGS. 9 and 12).

Subsequently, the polishing head 3 is lowered, and the small diameter portion 65 rolls upward of the side processing pad 54 while pressing the left and right center portions of the polishing tape T against the front surface of the side processing pad 54, and at the same time. The large-diameter portion 64 rolls upward of the side suction pad 55 while pressing the left and right edges of the polishing tape T against the front surface of the side suction pad 55. As a result, the left and right edges of the polishing tape T are fixed to the side suction pad 55 toward the upper side of the side suction pad 55, and the left and right edges of the polishing tape T are fixed toward the upper side of the side treatment pad 54. The central portion of the surface is laid and fixed so as to be in close contact with the side processing pad 54. The polishing head 3 is continuously lowered, and the polishing tape T is laid and fixed on the entire front surface of the side treatment pad 54, the small diameter portion 65 moves above the side treatment pad 54, and the large diameter portion 64 is on the side. When the polishing tape T is moved to the upper end portion of the side suction pad 55 and the left and right edge portions and the left and right center portions of the polishing tape T are fixed to the upper end portion of the side suction pad 55, the polishing tape T is attached to the head body 4. The mounting of the unused area is completed, and the lowering of the polishing head 3 is stopped (FIGS. 10 and 13).

While the tape mounting roller 63 is moving forward and the polishing head 3 is descending, the polishing tape T is pushed by the tape mounting roller 63, so that tension acts on the polishing tape T and the roll T1 is set. When a load equal to or greater than a set value is applied to the tape delivery reel 32, the rotation restriction of the tape delivery reel 32 by the rotation limiting unit 35 is released, and the tape delivery reel 32 rotates due to the tension. That is, when the unused polishing tape T is attached to the head body 4 as described above, the length of the polishing tape T between the rollers 43 and 44 is not insufficient. After the polishing tape T has been mounted as described above, the tape mounting roller 63 returns to the rear standby position, and the head body 4 rises to a predetermined position for cleaning the wafer W. (Fig. 11).

Subsequently, the cleaning process of the wafer W will be described. This cleaning process is performed by moving the polishing head 3, that is, the head body 4 up and down and left and right while the wafer W is rotated. 14 to 16 show the longitudinal side surfaces of the head body 4, the wafer W, and the polishing tape T during the cleaning process. In FIGS. 14 to 16, the peripheral edge of the wafer W is enlarged and shown in the circular frame to which the tips of the dotted arrows are connected.

Further, FIGS. 17 to 19 showing the positions of the frontmost ends of the rotating wafer W with respect to the side processing pad 54 and the lower processing pad 51 when viewed from the front as points P1 to P11 are also referred to as appropriate. During the cleaning process, the frontmost end of the wafer W moves points P1 to P11 in numerical order, and the arrows in FIGS. 17 to 19 indicate the locus of this movement. In addition, the height of the upper surface of the lower processing pad 51 changes by being pressed by the wafer W during the cleaning process, but in FIGS. 17 to 19, the case where the pressing is not performed is the case. The height of the upper surface of the lower processing pad 51 is shown. Further, FIG. 20 which is a plan view showing the positional relationship between the side processing pad 54 and the lower processing pad 51 and the wafer W is also referred to as appropriate. Unless otherwise specified in the following description, the notation on the right side and the left side shall be the right side and the left side when viewed from the front.

After the polishing tape T is attached to the head main body 4 as described with reference to FIGS. 8 to 13, the head main body 4 is arranged at a predetermined height and a predetermined left and right position. On the other hand, the wafer W is conveyed and placed on the spin chuck 25 at the retracted position by the conveying mechanism, and is attracted and held by the spin chuck 25. After that, the spin chuck 25 moves to the forward position, the side treatment pad 54 is pressed against the front end portion of the wafer W, and the side treatment pad 54 is deformed by its elasticity, so that the front end portion of the wafer W is the side treatment pad. It is buried in 54 and is in a state of receiving the restoring force of the side processing pad 54, and the peripheral edge portion of the wafer W on the right side of the front end portion enters the purge space 75 of the air supply / exhaust mechanism 7.

Then, when the head body 4 starts exhausting from the suction hole 53 and the supply / exhaust mechanism 7 starts discharging and exhausting the purge gas to form the air flow described with reference to FIG. 7, for example, clockwise in a plan view. The wafer W rotates. The thick arrow in FIG. 20 indicates the rotation direction of the wafer W. At this time, the frontmost end of the wafer W is located at the point P1 (see FIG. 17) on the right outer side of the side processing pad 54. In FIG. 20, the positions of the side processing pad 54 and the lower processing pad 51 when the foremost end of the wafer W is located at the point P1 are shown by solid lines.

Then, as the head body 4 descends, it moves to the right side. Due to the restoring force of the side processing pad 54 and the lowering of the head body 4, the upper inclined surface 12 and the side end surface 11 of the wafer W are pressed against the polishing tape T laid on the side processing pad 54, and are shown in FIG. As described above, the polishing tape T is in close contact with the polishing tape T. The upper inclined surface 12 and the side end surface 11 slide with respect to the polishing tape T by the rotation of the wafer W, unnecessary films and foreign substances on the upper inclined surface 12 and the side end surface 11 are removed, and cleaning proceeds. To do. At this time, the front end portion of the rotating wafer W buried in the side processing pad 54 receives an upward force due to the lowering of the head main body 4, but the head main body 4 is laterally moved during this lowering. Is also moving, so that the local position on the wafer W is prevented from receiving the above-mentioned upward force for a long time. Therefore, the above-mentioned cleaning proceeds while the wafer W is suppressed from being deformed by the above-mentioned upward force.

Then, when the frontmost end of the wafer W is located at the point P2 (see FIG. 17) on the left outer side of the side processing pad, the movement and lowering of the head body 4 to the right stop. In FIG. 20, the positions of the side processing pad 54 and the lower processing pad 51 when the foremost end of the wafer W is located at the point P2 are indicated by a chain line. After that, the head body 4 rises, and the foremost end of the wafer W moves to the point P3.

After that, the head body 4 moves to the left while the head body 4 continues to rise. Due to the restoring force of the side processing pad 54 and the rise of the head body 4, the lower inclined surface 13 and the side end surface 11 of the wafer W are pressed against the polishing tape T laid on the side processing pad 54, and FIG. As shown in the above, the polishing tape T is in close contact with the polishing tape T. The lower inclined surface 13 and the side end surface 11 slide with respect to the polishing tape T by the rotation of the wafer W, and unnecessary films and foreign substances on the lower inclined surface 13 and the side end surface 11 are removed for cleaning. Progresses. At this time, the front end portion of the rotating wafer W buried in the side processing pad 54 receives a downward force due to the head body 4 rising, but the head body 4 laterally moves during this rising. Also, the movement prevents the local position on the wafer W from receiving the downward force for a long time. Therefore, the above-mentioned cleaning proceeds while the wafer W is suppressed from being deformed by the above-mentioned downward force.

Then, when the foremost end of the wafer W moves to the point P4 (see FIG. 17) located vertically below the point P1 when viewed from the side processing pad 54 and the lower processing pad 51, the wafer W moves to the left side of the head body 4. Stops, the head body 4 continues to rise, and the foremost end of the wafer W is located at point P5. After that, the head main body 4 moves to the right side as it descends, and the upper inclined surface 12 and the side end surface 11 are cleaned in the same manner as when the front end of the wafer W moves from the points P1 to P2. After that, when the foremost end of the wafer W moves to the point P6 located vertically below the points P2 and P3 when viewed from the side processing pad 54 and the lower processing pad 51, the head body 4 moves to the right side. When stopped, the head body 4 rises and moves to the point P7, the head body 4 moves to the left while the head body 4 continues to rise, and the frontmost end of the wafer W moves from the point P3 to P4. As in the case, the lower inclined surface 13 and the side end surface 11 are cleaned.

While the front end of the wafer W is moving from the point P7 in this way, the peripheral edge of the back surface of the wafer W moves below the upper surface of the lower processing pad 51, thereby pressing the lower processing pad 51. The lower processing pad 51 is deformed by its elasticity. Then, when the frontmost end of the wafer W is located at the point P8, the polishing head 3 stops rising and moving to the left side. As shown in FIG. 17, this point P8 is inside the side processing pad 51 when viewed from the front. After that, the polishing head 3 moves to the right side. At this time, the restoring force of the lower processing pad 51 acts on the back surface peripheral region 14 of the wafer W in a state where the front end portion of the wafer W is buried in the side processing pad 54 and is restricted from going upward. The back surface peripheral region 14 is pressed against the lower processing pad 51, and is in close contact with the polishing tape T laid on the lower processing pad 51 as shown in FIG. In such a state, the back surface peripheral region 14 slides with respect to the polishing tape T by the rotation of the wafer W, unnecessary film and foreign matter in the back surface peripheral region 14 are removed, and cleaning proceeds.

Then, when the frontmost end of the wafer W is located at the point P9, the movement of the head body 4 to the right side is stopped. As shown in FIGS. 17 and 18, this point P9 is inside the side processing pad 51 when viewed from the front. After that, the head body 4 moves to the left side, the front end of the wafer W moves to the point P10 (see FIG. 18) at the same position as the point P8, and then the head body 4 moves to the right side to move the wafer. The foremost end of W moves to the point P11 (see FIG. 19) on the left outer side of the side processing pad 51. When the front end of the wafer W moves from the point P9 to P10 and from the point P10 to the point P11 in this way, the back surface is the same as when the front end of the wafer W moves from the point P8 to the point P9. The peripheral area 14 is cleaned.

After the front end of the wafer W moves to the point P11, the rotation of the wafer W is stopped, the exhaust from the suction hole 53 of the head body 4 is stopped, and the discharge and exhaust of the purge gas in the supply / exhaust mechanism 7 are stopped. Subsequently, the spin chuck 25 moves to the retracted position, and the wafer W is conveyed to the outside of the cleaning device 1 by a transfer mechanism (not shown). On the other hand, the head body 4 is lowered, the suction of the polishing tape T by the lower suction pad 52 and the side suction pad 55 is stopped, and the holding of the polishing tape T by the head body 4 is released. After that, the tape recovery reel 33 of the polishing head 3 rotates, and the used area of the polishing tape T held in the head body 4 is wound around the tape recovery reel 33 and the polishing tape T is unused. Is supplied from the roll T1 of the tape delivery reel 32 between the rollers 43 and 44 of the head body 4, and can be mounted on the head body 4 shown in FIG. After that, the polishing tape T described in FIGS. 5 to 13 is attached again, and then the cleaning process described in FIGS. 14 to 20 is performed on the wafer W newly carried into the cleaning device 1. ..

The cleaning device 1 includes a polishing head 3 including a side processing pad 54 that holds the polishing tape T on the side of the wafer W and a lower processing pad 51 that holds the polishing tape T below the peripheral edge of the wafer W. The peripheral portion of the wafer W is cleaned by advancing the spin chuck 25 that rotates the wafer W to the polishing head 3 and raising and lowering the polishing head 3. The side processing pad 54 is used for cleaning the side end surface 11, the upper inclined surface 12, and the lower inclined surface 13 of the wafer W, and the lower processing pad 51 is used for cleaning the back surface peripheral region 14 of the wafer W. By cleaning each surface of the wafer W with the two processing pads 51 and 54 in this way, it is not necessary to arrange the polishing head 3 in a different direction for each surface of the peripheral edge portion of the wafer W, so that the wafer W is processed. It is possible to reduce the time required for. Further, the side processing pad 51 is made of an elastic body, and the polishing head 3 moves up and down with the front end portion of the rotating wafer W buried in the side processing pad 51, and the sides of the wafer W having different orientations from each other. Since the end surface 11, the upper inclined surface 12, and the lower inclined surface 13 are cleaned, the time required for processing the wafer W can be suppressed more reliably.

A rotation mechanism for rotating the polishing head 3 around the horizontal axis is provided, and the side processing pad 51 uses the side end surface 11 to clean the side end surface 11, the upper inclined surface 12, and the lower inclined surface 13, respectively. The polishing heads 3 may be oriented in different directions so that the upper inclined surface 12 and the lower inclined surface 13 are opposed to each other and are in close contact with each other, so that each of these surfaces may be polished. Even in such a configuration, the back surface peripheral region 14 of the wafer W is cleaned by the lower processing pad 51 so that the side processing pad 51 faces the back surface peripheral region 14. Since it is not necessary to arrange them so as to be in close contact with each other, the amount of movement of the polishing head 3 during the cleaning process can be suppressed, so that the time required for processing the wafer W can be suppressed.

Further, according to the cleaning device 1, the polishing tape T is reliably held by the head body 4 by sucking the back surface of the polishing tape T by the lower suction pad 52 and the side suction pad 55 provided on the head body 4. Can be made to. An adhesive material is provided on the back surface of the polishing tape T, and when the polishing tape T is pressed against the lower processing pad 51 and the side processing pad 54 by the tape mounting roller 63, the polishing tape is acted by the action of the adhesive material. T may be held by the lower suction pad 52 and the side suction pad 55. In that case, in order to remove the polishing tape T from the head main body 4, the polishing tape T adhered to the head main body 4 is peeled off by rotating the tape collecting reel 33 and applying tension to the polishing tape T. However, in order to prevent the adhesive material from remaining as a foreign substance on the head body 4, it is preferable to suck and hold the polishing tape T as described above.

Further, the cleaning device 1 includes an air supply / exhaust mechanism 7 provided independently of the polishing head 3, that is, a supply / exhaust mechanism 7 provided so as not to move in accordance with the movement of the polishing head 3. Since it is independent of the polishing head 3 in this way, the position of the air supply / exhaust mechanism 7 with respect to the rotating wafer W is fixed, and the movement of the polishing head 3 may disturb the air flow formed in the purge space 75. There is no. Therefore, by providing the air supply / exhaust mechanism 7, shavings can be removed more reliably. However, the air supply / exhaust mechanism 7 may be configured to move together with the polishing head 3.

The tape mounting roller 63 of the tape mounting mechanism 6 may be configured such that the small diameter portion 65 is not provided and only the large diameter portion 64 is provided, but the polishing tape T is provided on the lower processing pad by the small diameter portion 65. It is pressed against the 51 and the side treatment pad 54, and the tape T can be brought into close contact with the lower treatment pad 51 and the side treatment pad 54 without loosening. Therefore, it is preferable to provide the small diameter portion 65 because the cleaning performance can be improved.

Further, when the suction force of the lower suction pad 52 and the side suction pad 55 is relatively large, the polishing tape T is brought close to the lower suction pad 52 and the side suction pad 55 without being pressed by the tape mounting mechanism 6. Even in this case, the lower suction pad 52 and the side suction pad 55 can be used for suction. Therefore, the pressing mechanism for pressing the polishing tape T is not limited to the provision of a rolling element that rolls the lower suction pad 52 and the side suction pad 55.

Therefore, for example, by moving the head body 4 relative to the wafer W held by the spin chuck 25, the polishing tape T is pressed toward the head body 4 by the wafer W and brought close to the head body 4. 4 may hold the polishing tape T. That is, the tape mounting mechanism 6 does not have to be provided in the cleaning device 1, but it is preferable that the tape mounting mechanism 6 is provided in order to more reliably hold the polishing tape T in the head body 4. The rolling element support portion 62 of the tape mounting mechanism 6 may be provided with a sphere as a rolling element instead of the tape mounting roller 63, and the polishing tape T may be pressed against the head body 4 by the sphere.

Although the wafer W is advanced toward the head body 4 for processing, a moving mechanism for moving the head body 4 back and forth is provided, and instead of advancing the wafer W in this way, the head body is directed toward the wafer W. The process may be performed by retreating 4. Further, although the processing is performed by raising and lowering the head body 4, a lifting mechanism for raising and lowering the spin chuck 25 is provided, and instead of raising and lowering the head body 4 in this way, the processing is performed by raising and lowering the spin chuck 25. You may.

By the way, regarding the polishing head, one end side of the polishing tape T in the length direction is held by the side processing pad 54 and the side suction pad 55, and the other end side is held by the lower treatment pad 51 and the lower suction pad 52. The configuration of the polishing head 3 is not limited to the above. FIG. 21 shows a schematic front view of the polishing head 84. The difference from the polishing head 3 described above is that the polishing head 84 is provided with two sets of tape delivery reels 32 and tape recovery reels 33, and the tape delivery reels 32 and tape recovery reels 33 forming the same set are heads. It is provided on the left and right sides of the main body 4. A set of tape sending reels 32 and tape collecting reels 33 rotate around a horizontal axis along the front and back, and the polishing tape T (indicated by a dotted line in the figure) between these reels 32 and 33 is on the lower side. It is held by the processing pad 51 and the lower suction pad 52. The other set of tape sending reels 32 and tape collecting reels 33 rotate around the vertical axis, and the polishing tape T (indicated by a chain line in the figure) between these reels 32 and 33 is the side processing pad 54 and. It is held by the side suction pad 55. However, since the polishing head 84 requires a plurality of reels 32 and 33, a motor 34 to which the reels 32 and 33 are connected, and a rotation limiting portion 35, it is preferable to configure the polishing head 3. ..

The shapes of the lower suction pad 52 and the side suction pad 55 are not limited to the above examples, and are designed to surround the entire circumference of the lower treatment pad 51 and the side treatment pad 54. Alternatively, the left and right may be divided so as to sandwich the lower processing pad 51 and the side processing pad 54 from the left and right. Even when the suction pads are arranged only on the left and right sides of the processing pad and not before, after, or above and below the processing pad, the suction pads are included in the case where they are arranged around the processing pad. Further, the suction hole 53 of the head body 4 is not limited to being provided in the base portion 42 as described above, and may be provided on the left and right outer sides of the wall portion 41 where the polishing tape T is held, for example. The present invention is not limited to the above-described examples, and each example can be appropriately modified or combined.

T Polishing tape W Wafer 1 Cleaning device 10 Control unit 23 Rotating mechanism 24 Back and forth movement mechanism 25 Spin chuck 3 Polishing head 4 Head body 51 Lower processing pad 52 Lower suction pad 54 Side treatment pad 55 Side suction pad 6 Tape mounting Mechanism 7 Air supply / exhaust mechanism

Claims (13)

The board holding part that holds the board and
A rotation mechanism for rotating the substrate held by the substrate holding portion, and
A polishing head including a first tape holding portion that holds the polishing tape on the side of the substrate and a second tape holding portion that holds the polishing tape below the substrate.
With a forward mechanism that advances the substrate holding portion relative to the polishing head so that the side surface of the rotating substrate slides on the polishing tape held by the first tape holding portion and is cleaned. ,
An ascending mechanism that raises the polishing head relative to the substrate so that the lower surface of the rotating peripheral edge of the substrate is slid and cleaned by the polishing tape held by the second tape holding portion. When,
A cleaning device for a peripheral portion of a substrate, which comprises. Claim 1 is characterized in that one end side of the polishing tape in the length direction is held by the first tape holding portion, and the other end side of the polishing tape in the length direction is held by the second tape holding portion. The cleaning device for the peripheral edge of the substrate according to the description. The cleaning device for a peripheral edge of a substrate according to claim 2, wherein the polishing head is provided with suction holes for sucking shavings on the left and right outside of a region where the polishing tape is held. At least one of the first tape holding portion and the second tape holding portion is
A substrate pressing portion where the polishing tape is brought into close contact with the substrate and pressed against the substrate via the polishing tape.
A tape suction portion provided around the substrate pressing portion and sucking the polishing tape so that the polishing tape is brought into close contact with the substrate pressing portion.
The cleaning device for a peripheral portion of a substrate according to any one of claims 1 to 3, wherein the device is provided with. The substrate pressing portion has a contact surface to which the polishing tape is adhered.
The substrate according to claim 4, wherein the tape suction portion includes a suction surface provided with a suction hole for sucking the polishing tape, which is provided at a position lower than the contact surface when viewed from the contact surface. Peripheral cleaning device. The suspension portion for suspending the polishing tape on the substrate pressing portion and the tape suction portion and the end portion in the length direction of the polishing tape are pulled and suspended on the substrate pressing portion and the tape suction portion. A tape feeding mechanism for moving the region in the length direction of the polishing tape is provided on the polishing head.
4. The fourth aspect of the present invention is characterized in that a pressing mechanism for pressing the unused area of the polishing tape suspended on the suspended portion toward the tape suction portion is provided in order to attract the unused area of the polishing tape by the tape suction portion. 5. The substrate peripheral peripheral cleaning device according to 5. The cleaning device for a peripheral edge of a substrate according to claim 6, wherein the pressing mechanism includes a first rolling element that rolls the tape suction portion and presses the polishing tape against the tape suction portion. The peripheral portion of the substrate according to claim 6 or 7, wherein the pressing mechanism includes a second rolling element that rolls the substrate pressing portion and presses the polishing tape against the substrate pressing portion. Cleaning equipment. The ascending mechanism is an elevating mechanism that elevates and elevates the polishing head relative to the rotating substrate.
The first tape holding portion includes the substrate pressing portion.
The substrate pressing portion is composed of an elastic body.
The polishing head is relatively moved with respect to the substrate by the elevating mechanism in a state where the peripheral edge of the rotating substrate is pressed against the substrate pressing portion and the restoring force of the substrate pressing portion acts on the substrate. The cleaning device for a peripheral edge of a substrate according to any one of claims 1 to 8. A left-right movement mechanism for moving the polishing head to the left and right relative to the rotating substrate is provided.
With the restoring force of the substrate pressing portion acting on the substrate, the relative movement of the polishing head with respect to the substrate by the elevating mechanism and the relative movement of the polishing head with respect to the substrate by the left-right movement mechanism are performed together. The cleaning device for a peripheral edge of a substrate according to claim 9. The upper and lower surfaces of the rotating substrate are provided with a purge gas discharge port for discharging purge gas for removing shavings and an exhaust port for exhausting from the outside of the substrate, and are provided independently of the polishing head. The cleaning device for a peripheral edge of a substrate according to any one of claims 1 to 10, further comprising an exhaust mechanism. The process of holding the board by the board holding part and
The step of rotating the substrate held by the substrate holding portion and
A step of holding the polishing tape on the side of the substrate and below the substrate by the first tape holding portion and the second tape holding portion constituting the polishing head, respectively.
A step of advancing the substrate holding portion relative to the polishing head so that the side surface of the rotating substrate slides on the polishing tape held by the first tape holding portion and is cleaned.
A step of raising the polishing head relative to the substrate so that the lower surface of the rotating peripheral edge of the substrate is slid and cleaned by the polishing tape held by the second tape holding portion. ,
A method for cleaning the peripheral edge of a substrate, which comprises. In a storage medium that stores a computer program used in a cleaning device that slides the peripheral edge of a substrate onto a polishing tape for cleaning.
The computer program is a storage medium in which a group of steps is assembled so as to execute the method for cleaning the peripheral edge of the substrate according to claim 12.

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