TW201818502A - Chuck structure and chuck portion - Google Patents

Abstract

The invention provides a simple chuck structure capable of chucking a wafer reliably and having excellent corrosion resistance. The chuck structure includes: a disc-shaped stage 3 capable of rotating in a plane direction; at least three chuck portions 5 disposed with equal intervals along a circumference of which the center is the rotation axis of the stage 3, and surrounding the end surface 103 of a wafer 10 in a rotatable manner along the diameter direction of the stage 3; and a holding portion 7 disposed on the stage 3 to hold the chuck portion 5 in a rotatable manner. The center of gravity G of the chuck portion 5 is located outside a rotating center axis C in the diameter direction of the stage 3 and lower than the rotating center axis C.

Description

 Chuck mechanism and clip head  

The invention relates to a collet mechanism and a collet head.

As a device for washing and drying a substrate such as a semiconductor wafer, a conventional one uses a batch type, and a plurality of substrates are immersed in a cleaning layer to be washed, and then pulled up from the cleaning layer and dried. .

The batch type can process a plurality of substrates at the same time, so the work efficiency is excellent, but in order to further improve the cleaning degree of the substrate, the substrate is rotated one by one on the platform and sprayed with the washing liquid, and then the dried leaves are dried. The formula is more favorable.

Leafy wash. In the drying device, it is necessary to hold the chuck portion of the substrate. Patent Document 1 discloses a structure in which a plurality of clamp arms constituting a substrate support portion are connected to a cylindrical device that is moved in a vertical direction through a connection line. In this configuration, when the cylinder device is raised, the wire pulls the clamp arm to sandwich the substrate, and the cylinder device is lowered to release the clamping operation.

Leafy wash. In the drying device, due to the centrifugal force during rotation, the vicinity of the outer periphery of the platform may be deformed in the direction of the rotating shaft to cause the collet to fall off. Patent Document 2 discloses a structure in which a weight that can be moved in a radial direction is placed under a platform and held by a spring that is stretched and contracted in a radial direction. In this configuration, the weight is moved to the outer peripheral side by the centrifugal force against the elastic force of the spring when rotating, thereby preventing deformation near the outer periphery of the platform, so that the chuck does not fall off.

Leafy wash. In the drying apparatus, when the chuck head is always in contact with the wafer during washing, the contact portion is not washed and the washing residue may occur. In Patent Document 3, as a clip head, a support rod that supports a substrate only at a high speed rotation is disclosed. The support rod is pivoted about the center of the pivot, thereby contacting and holding the substrate than the upper portion of the pivot. The portion of the support rod that is higher than the pivot will have a lower mass than the lower portion, and the lower portion will be pushed by the spring to the platform side. The support rod does not sandwich the substrate at the time of low-speed rotation, but at the time of high-speed rotation, the lower side portion is moved to the opposite side of the platform side by centrifugal force against the urging force of the spring, thereby contacting and holding the substrate. After washing, when the centrifugal force is lowered and the support rod is detached, the washing liquid flows to the contact portion, so that the washing liquid does not remain.

 [First technical literature]  

Patent Document 1: Japanese Laid-Open Patent Publication No. 2001-223198

Patent Document 2: Japanese Patent Laid-Open Publication No. 2010-10221

Patent Document 3: Japanese Laid-Open Patent Publication No. 2001-110771

However, the structures described in Patent Document 1 to Patent Document 3 have the following problems.

In the structure of Patent Document 1, the chuck mechanism requires a cylinder and a wire, and there is a problem that the structure is complicated and the cost is increased. When these parts are made of metal, there is a possibility that the cleaning liquid or the corrosive gas generated by the washing liquid spray may corrode.

The structure of Patent Document 2 is a relatively simple structure. However, in order to surely sandwich the wafer, it is necessary to finely adjust a plurality of weights and springs, and there is a problem that workability is poor, and the general spring is made of metal. There are problems with corrosion.

The structure of Patent Document 3 is a relatively simple structure, but a spring is required, and there is still a problem of corrosion.

In view of the above problems, the present invention has been proposed to provide a chuck mechanism and a chuck which are simple in construction and capable of sandwiching a wafer and having excellent corrosion resistance.

The chuck mechanism of the present invention holds the wafer in a leaflet type, and includes a disk-shaped platform that can be rotated in the plane direction; and three or more chuck heads are equally arranged on the circumference around the rotation axis of the platform. And surrounding the end surface of the wafer in a radial direction of the platform; and a holding portion disposed on the platform to rotatably hold the chuck head, wherein the center of gravity of the chuck head It is located on the outer side in the radial direction of the platform than the central axis of rotation and on the lower side than the central axis of rotation. According to the present invention, since the center of gravity of the chuck head is located more outward and lower than the center of rotation, the smaller the centrifugal force of the rotation of the platform, the head of the chuck rotates away from the wafer, and the centrifugal force of the rotation of the platform is larger. The head will turn in the direction of approaching the wafer. Therefore, if the rotation speed of the platform is below a certain level, the wafer is surely released, and if it is more than a certain level, the wafer is surely clamped. This mechanism can specify only the relationship between the central axis of rotation and the position of the center of gravity, and does not require a spring or a weight, etc., and is realized by a simple structure. When the structure is simple, it is possible to form the chuck portion by using a resin or a molded member without using a spring or a complicated member, and thus the corrosion resistance can be improved.

In the chuck mechanism of the present invention, the chuck head includes: a chuck body having a rod shape, the end surface of the holding portion being held as one end with the upper end facing upward; and the wafer holding portion having the lower holding portion and the end surface a clamping portion, the lower holding portion is disposed at an upper end of the chuck body and has a supporting surface contacting and supporting the lower surface of the wafer, the end surface clamping portion having a holding surface contacting and holding an end surface of the wafer; a rotation center a hole formed in the chuck body perpendicular to a radial direction of the platform and an axial direction of the chuck body; and a meandering portion disposed at a lower end of the chuck body, bent in a radial direction of the platform to The outside of the collet body. The holding portion includes a through shaft that is provided to penetrate the rotation center hole, and a base portion that is provided on the platform to fix the through shaft. According to the present invention, the meandering portion that is bent to the outside of the chuck body is provided to the lower end of the chuck body, whereby the center of gravity of the chuck portion can be positioned further outward and lower than the central axis of rotation, so that the structure is simple. When the structure is simple, it is possible to form the chuck portion by using a resin or a molded member without using a spring or a complicated member, and thus the corrosion resistance can be improved.

The chuck mechanism of the present invention further includes: a long hole which is provided in a radial direction of the platform to be lower than a rotation center hole of the chuck body; and a guide rod having a round bar shape, which penetrates the length Set the hole. The long hole is provided in a sliding contact with the guide rod in the circumferential direction of the platform, and the radial length in the up and down direction is larger than the diameter of the guide rod. According to the present invention, the rotational moment generated by the through shaft due to the rotation of the platform can be relieved by the side of the guide rod contacting the long hole, so that the chuck mechanism can be prevented from being deformed by the rotational moment when the platform rotates.

In the chuck mechanism of the present invention, the chuck body, the wafer holding portion, and the meandering portion are integrally formed. According to this configuration, the clip head can be manufactured by integral molding such as resin molding, and thus corrosion resistance can be improved.

In the chuck mechanism of the present invention, the end surface holding portion includes: a protruding portion that is erected from the chuck body and has an abutting surface that abuts against an end surface of the wafer; and a drain along the platform The radial direction is set in the protrusion. According to this invention, the abutting surface at the time of clamping comes into contact with the end surface of the wafer, so that it can be surely caught. Further, according to this configuration, when the wafer is rotated while being rotated, the cleaning liquid is discharged from the drain due to the centrifugal force, and the cleaning liquid can be prevented from remaining between the end surface holding portion and the end surface of the wafer to contaminate the wafer.

In the chuck mechanism of the present invention, the lower holding portion includes a tapered portion that is inclined upward from an inner side in a radial direction of the platform toward an outer side, wherein the support surface is an upper surface of the tapered portion. According to the present invention, when the rotational speed of the stage is constant or less and the chuck portion is rotated in a direction away from the wafer, the contact angle between the lower surface of the wafer and the upper surface of the tapered portion can be made small, and the crystal can be prevented from being damaged during contact. circle.

In the chuck mechanism of the present invention, the chuck portion is made of polyvinyl chloride or polyetheretherketone. According to the present invention, the chuck portion can be formed of a material that is lightweight, inexpensive, and highly resistant to corrosion, and the corrosion resistance of the chuck mechanism can be improved.

The chuck head of the present invention is a chuck mechanism for holding a wafer by leaf rotation, comprising: a chuck body having a rod shape; and rotating a center hole to be perpendicular to an axial direction of the chuck body The method is formed on the chuck body; the wafer holding portion has an end portion disposed on one side of the chuck body and faces a surface in a clamping direction perpendicular to both the chuck body and the rotation center hole. In the pinching direction, the center of gravity is located outside the direction in which the wafer is sandwiched by the center hole of the rotation, and in the axial direction of the body of the chuck, the center of gravity is located on the wafer relative to the center hole of the rotation. The opposite side of the department. According to the present invention, since the center of gravity of the chuck head is located more outward and lower than the center of rotation, the smaller the centrifugal force of the rotation of the platform, the head of the chuck rotates away from the wafer, and the centrifugal force of the rotation of the platform is larger. The head will turn in the direction of approaching the wafer. Therefore, if the rotation speed of the platform is below a certain level, the wafer is surely released, and if it is more than a certain level, the wafer is surely clamped. This mechanism can specify only the relationship between the center axis of rotation and the center of gravity, and does not require a spring or a weight, etc., and is realized by a simple structure. When the structure is simple, it is possible to form the chuck portion by using a resin or a molded member without using a spring or a complicated member, and thus the corrosion resistance can be improved.

1‧‧‧chuck mechanism

3‧‧‧ platform

5‧‧‧ Clip head

7‧‧‧ Keeping Department

9‧‧‧ Guide rod

11‧‧‧Keyboard

13‧‧‧Clip head insertion hole

15‧‧‧ convex insertion hole

17‧‧‧ Guide rod insertion hole

19‧‧‧Holding hole

20‧‧‧Rotating center hole

21‧‧‧Keyboard fixing holes

31‧‧‧ chuck body

33‧‧‧ Wafer Holder

34‧‧‧Upper

35‧‧‧The following keeping department

36‧‧‧Bottom

37‧‧‧Abutment

39‧‧‧drain

41‧‧‧End face clamping

43‧‧‧Rotating center hole

45‧‧‧Zigzag

47‧‧‧ long hole

51‧‧‧ base

53‧‧‧Insert hole

55‧‧‧through shaft holding unit

57‧‧‧through shaft holding unit

59‧‧‧through shaft

61‧‧‧ head

63‧‧‧C ring

65‧‧‧ Keeping side through hole

71‧‧‧ Spindle

73‧‧‧fixed pin

75‧‧‧ Ring

77‧‧‧ front end

81‧‧‧ board body

83‧‧‧ Guide rod through hole

85‧‧‧ convex

87‧‧‧ plate through hole

100‧‧‧ wafer

103‧‧‧ end face

105‧‧‧ below

C‧‧‧Center of rotation

G‧‧‧ center of gravity

Fig. 1 is a perspective view of a chuck mechanism of an embodiment of the present invention.

Fig. 2 is a perspective view of the platform of the above embodiment.

Fig. 3 is a perspective view of the clip head of the field A of Fig. 1 of the above embodiment.

Fig. 4 is a side view of the clip head of the above embodiment.

Fig. 5 is a perspective view of the holding portion of the above embodiment.

Fig. 6 is a perspective view of the guide rod of the above embodiment.

Fig. 7 is a perspective view of the keypad of the above embodiment.

Fig. 8 is a perspective view showing a state in which a wafer is mounted on the chuck mechanism of the above-described embodiment.

Fig. 9 is a side view showing a state in which the wafer is mounted in a state where the rotation of the stage is stopped in the above embodiment.

Fig. 10 is a side view showing a state in which the wafer is mounted in a state in which the stage is rotated in the above embodiment.

Embodiments suitable for the present invention will be described in detail below based on the drawings. First, the structure of the chuck mechanism 1 of the present embodiment will be described with reference to Figs. 1 to 7 . Here, as the chuck mechanism, the holding mechanism at the time of wafer cleaning and drying after washing is exemplified.

As shown in Fig. 1, the chuck mechanism 1 is a device for holding a wafer 100 (see Fig. 8) to be described later in a leaf type, and has a stage 3, a chuck portion 5, and a holding portion 7. The chuck mechanism 1 also has a guide rod 9 and a key sheet 11.

The stage 3 is a disk-shaped member in which each constituent member of the chuck mechanism 1 is mounted. As shown in FIG. 2, the stage 3 is rotatable in the plane direction centering on the rotation center O. The platform 3 is preferably made of a material having corrosion resistance to the cleaning liquid, and is made of, for example, polyvinyl chloride or polyether ether ketone. The stage 3 forms a rotation center hole 20 at the center of rotation O as shown in FIG. The rotation center hole 20 is a hole to which a rotation shaft of a rotation motor (not shown) is attached.

As shown in Fig. 2, the platform 3 is provided with a chuck insertion hole 13 and a holding portion fixing hole 19 on the outer periphery of the upper surface. The stage 3 has a convex insertion hole 15 formed in the radial direction of the stage 3 from the outer peripheral end surface toward the chuck insertion hole 13. The platform 3 also has a key plate fixing hole 21 provided on both sides of the convex portion insertion hole 15 of the outer peripheral end surface.

The chuck insertion hole 13 is a hole into which the chuck portion 5 is inserted, and is disposed on the circumference centering on the rotation center O. Here, the six positions along the outer circumference of the platform 3 are equally arranged. The inner circumference of the chuck insertion hole 13 is formed with a guide rod insertion hole 17 that opens toward the rotation center O and allows the front end of the guide rod 9 to be inserted.

The holding portion fixing hole 19 is an insertion hole for a screw or the like (not shown) that fixes the holding portion 7, and is provided at four positions around the chuck insertion hole 13. The convex insertion hole 15 is a hole into which the key sheet 11 is inserted. The key plate fixing hole 21 is a hole into which a screw or the like (not shown) that fixes the key plate 11 is inserted.

The chuck portion 5 is a member rotatable in the radial direction of the stage 3, and is a member that holds the wafer 100 by rotation. The chuck portion 5 is preferably made of a material having corrosion resistance to the cleaning liquid, and is made of, for example, polyvinyl chloride or polyether ether ketone. The chuck portion 5 is equally disposed on the circumference centered on the rotation center O of the platform 3 in Fig. 1, and here, six end faces 103 surrounding the wafer 100 are provided along the outer circumference of the stage 3 (refer to Fig. 9). ). The number of the clip heads 5 is not limited to six. However, when holding and holding the wafer 100, it is preferable to have at least three in order to prevent stress from being generated on the wafer 100. As shown in FIG. 3, the chuck portion 5 has a chuck body 31 and a wafer holding portion 33. The chuck head 5 also has a rotation center hole 43, a meandering portion 45, and a long hole 47.

The chuck body 31 is a member having a rod shape, and one end portion is an upper end 34 and is held upward by the holding portion 7. The wafer holding portion 33 is a member that rises from the upper end 34 of the chuck body 31 to the upper side (positive Z direction). The lower holding portion 35 and the end surface holding portion 41 are provided.

The lower holding portion 35 is a member that contacts and supports the lower surface 105 (see FIG. 9) of the wafer 100, and in FIG. 3, a tapered portion that is inclined upward from the inner side in the radial direction of the stage 3. In this configuration, a support surface supporting the lower surface 105 of the wafer 100 is formed on the upper surface of the tapered portion.

The end surface holding portion 41 is a member that cooperates with the other chuck 5 by the end surface 103 of the wafer 100 (see FIG. 9), and sandwiches and holds the wafer 100. The end surface holding portion 41 is provided on the outer side in the radial direction of the stage 3 of the lower surface holding portion 35, and is a pair of protruding portions facing the chuck direction (the radial direction of the stage 3).

A drain groove 39 is provided between the pair of end face holding portions 41 along the radial direction of the stage 3. When the wafer 100 is held by the chuck mechanism 1 and rotated, the drain groove 39 is washed to prevent the cleaning liquid from remaining between the end surface holding portion 41 and the end surface 103 of the wafer 100. The drain of the liquid.

The end surface holding portion 41 has a pair of abutting faces 37 that are in contact with the wafer 100 as a holding surface. The abutting surface 37 includes a surface that faces the drain groove 39, and a curved surface is formed in the vicinity of the corner portion on the inner side in the radial direction of the platform 3.

The rotation center hole 43 is a through hole that forms a center when the chuck body 31 is rotated, and is provided on the lower side of the wafer holding portion 33. The rotation center hole 43 is formed in a direction perpendicular to both the radial direction of the stage 3 (the direction in which the wafer head 100 is sandwiched by the chuck portion 5) and the axial direction of the chuck body 31 (the Y direction in FIG. 3).

The meandering portion 45 is a portion for setting the position of the center of gravity of the chuck portion 5 at a desired position. The meandering portion 45 is a rod-shaped member provided at the lower end 36 of the chuck body 31. The meandering portion 45 is bent toward the outer side of the chuck body 31 in the radial direction of the stage 3.

The long hole 47 is a through hole into which the guide rod 9 is inserted. The long hole 47 is formed on the lower side (the side of the meandering portion 45) of the rotation center hole 43 and penetrates the radial direction of the stage 3, that is, the direction perpendicular to the rotation center hole 43. The height h of the vertical direction of the long hole 47 (the axial direction of the chuck main body 31, here, the Z direction) is larger than the diameter DL of the main shaft 71 of the guide rod 9 (refer to Fig. 6). The width W of the land 3 of the long hole 47 in the circumferential direction (Y direction) is a length that is slidable in contact with the main shaft 71 of the guide rod 9 (a length equal to the diameter DL of the main shaft 71).

The clip head 5 is preferably constructed in one piece. Specifically, the chuck body 31, the wafer holding portion 33, and the meandering portion 45 are preferably integrally formed. This is because the integrated head structure can integrally form the chuck portion 5 by resin molding or the like to improve corrosion resistance.

As shown in FIG. 4, the center of gravity G of the chuck portion 5 must be located outside the radial direction axis C in the radial direction of the platform 3 (the direction in which the wafer 100 is sandwiched), and is lower than the rotation center axis C ( The wafer holding portion 33 is opposite to the rotation center axis C).

The holding portion 7 is a member that rotatably holds the chuck portion 5. As shown in Fig. 1, it is placed on the platform 3. As shown in FIG. 5, the holding portion 7 has a through shaft 59, a base portion 51, through shaft holding portions 55, 57, and a C ring 63.

The through shaft 59 is a shaft that holds the chuck head 5 and forms a head portion 61 whose diameter is increased at one end. Although the other end portion is not shown, the outer peripheral surface is formed with a groove around the shaft. The base portion 51 is a plate-shaped member fixed to the platform 3, and an insertion hole 53 for inserting the clip head portion 5 is formed at the center. At four positions around the insertion hole 53 of the base portion 51, a holding portion side through hole 65 corresponding to the holding fixing hole 19 of Fig. 2 is formed. The holding portion side through hole 65 is inserted by a screw or the like (not shown) for fixing the holding portion 7 to the stage 3 .

The through shaft holding portions 55 and 57 are semicircular plate-like members that are disposed opposite to each other with the insertion hole 53 interposed therebetween. The through hole 59 is provided to pass through the through shaft holding portions 55 and 57 through the insertion hole 53.

The C ring 63 is prevented from coming off the through shaft holding portions 55 and 57 by being fitted into a notch (not shown) formed at the other end portion of the through hole 59. The C-ring 63 is preferably made of a material having elasticity capable of withstanding deformation when the through-shaft 59 is fitted and corrosion resistance to a cleaning liquid or the like. Such materials are, for example, fluororesins. The member of the holding portion 7 other than the C-ring 63 preferably has a corrosion resistance to a cleaning liquid or the like, and is preferably made of a material having a higher strength than the C-ring 63. This material is composed of, for example, polyvinyl chloride or polyetheretherketone. The screw (not shown) in which the holding portion 7 is fixed to the stage 3 is preferably made of a material having corrosion resistance to the cleaning liquid, similarly to the holding portion 7.

The guide rod 9 is a rod-shaped member for mitigating a rotational moment generated on the Y-Z plane of the through shaft 59 when the stage 3 is rotated. The guide rod 9 is preferably made of a material having corrosion resistance to a cleaning liquid or the like. This material is composed of, for example, polyvinyl chloride or polyetheretherketone. As shown in Fig. 6, the guide rod 9 is provided with a main shaft 71, a ring 75, and a fixing pin 73.

The main shaft 71 is a rod-shaped shaft that penetrates the long hole 47 shown in Fig. 3 . When the main shaft 71 rotates by the platform 3, it comes into contact with the side surface of the long hole 47 and slides, and a part of the rotational moment generated by the chuck head 5 is received, and the rotation torque is prevented from being concentrated and deformed by the through hole 59.

The end of one side of the main shaft 71 is the front end portion 77 inserted into the guide rod insertion hole 17 of Fig. 2 . The ring 75 is a member provided at the other end of the main shaft 71 and has a larger diameter than the main shaft 71. The ring 75 is a member that fixes the position of the guide rod 9 and at the same time makes the clip head 5 rotatable. Specifically, the guide rod 9 is inserted into the guide rod insertion hole 17, and when the front end portion 77 abuts, the position of the guide rod 9 is fixed by the key sheet 11 of the first figure, and the position of the guide rod 9 is fixed. Rotatable gap.

The fixing pin 73 is a rod-shaped member that extends from the end of the ring 75 in a direction opposite to the main shaft 71. The fixing pin 73 is a member that passes through the key sheet 11 of Fig. 1 and determines the position of the guide rod 9, and has a smaller diameter than the main shaft 71 and the ring 75.

The key sheet 11 is a member that fixes the guide rod 9 to the stage 3. The key sheet 11 is preferably made of a material having corrosion resistance to a cleaning liquid or the like. This material is composed of, for example, polyvinyl chloride or polyetheretherketone.

As shown in Fig. 7, the key sheet 11 includes a plate body 81, a convex portion 85, a guide rod through hole 83, and a plate fixing through hole 87.

The plate body 81 is a plate-shaped member that contacts the outer circumference of the stage 3. The convex portion 85 is a member that protrudes from the inner surface of the plate body 81 (the surface that is in contact with the platform 3), and has a shape corresponding to the convex portion insertion hole 15 of Fig. 2 .

The guide rod through hole 83 is a hole into which the fixing pin 73 of Fig. 6 is inserted, and penetrates the plate body 81 and the convex portion 85 in the radial direction of the stage 3.

The plate fixing through hole 87 is a hole corresponding to the key plate fixing hole 21 of Fig. 2, and a screw or the like (not shown) that fixes the plate body 81 to the stage 3 is inserted. Similarly to the key sheet 11, the screw (not shown) is preferably made of a material having corrosion resistance to the cleaning liquid.

The above is an explanation of the structure of the chuck mechanism 1.

Next, an example of a method of assembling the chuck mechanism 1 will be briefly described.

First, the base portion 51 of the holding portion 7 is attached to the platform 3. Specifically, the holding portion side through hole 65 of the substrate 51 shown in FIG. 5 is aligned with the position of the holding portion fixing hole 19 of the stage 3 shown in FIG. 1 , and a screw or the like (not shown) is inserted into the holding portion 7 . Fixed to platform 3.

Next, the chuck portion 5 is inserted into the chuck insertion hole 13 of the stage 3 shown in Fig. 2 from below. In this state, the through shaft 59 of the holding portion 7 is inserted into the rotation center hole 43 shown in Fig. 3, and the C ring 63 is fitted into a groove (not shown), whereby the chuck portion 5 is fixed to the base portion 51.

Next, the main shaft 71 of the guide rod 9 shown in Fig. 6 is inserted into the long hole 47 of the chuck portion 5 shown in Fig. 3, and the distal end portion 77 is inserted into the guide rod insertion hole 17 shown in Fig. 2 . Finally, as shown in Fig. 1, the key sheet 11 is attached to the stage 3, and the fixing pin 73 is inserted into the guide rod through hole 83. Specifically, the convex portion 85 shown in Fig. 7 is inserted into the convex portion insertion hole 15 shown in Fig. 2, and a screw or the like (not shown) is inserted into the plate fixing through hole 87 and the second shown in Fig. 7 . The keypad is shown in the figure as a fixing hole 21. The chuck mechanism 1 is assembled by the above steps.

As shown in Fig. 9, the center of gravity G of the chuck portion 5 is located on the outer side in the radial direction of the platform 3 from the central axis of rotation C and on the lower side than the central axis C of rotation. Therefore, when the stage 3 is not rotated in the state in which the chuck mechanism 1 is assembled, the main shaft 71 of the chuck head 5 is maintained in a state in which the axial direction is horizontally oriented in the vertical direction (Z direction) toward R1.

At this time, the distance DC between the rotation center O of the platform 3 and the abutment surface 37 of the chuck head 5 is larger than the radius DW of the wafer 100. The above is an explanation of an example of the method of assembling the chuck mechanism 1.

Next, the operation when the chuck mechanism 1 sandwiches the wafer 100 will be described with reference to FIGS.

First, in a state where the stage 3 is stationary, as shown in FIG. 8, the wafer 100 is mounted on the chuck mechanism 1. Specifically, as shown in FIG. 9, the wafer 100 is mounted so that the lower surface 105 is in contact with the lower surface holding portion 35.

In this state, as shown in FIG. 9, the end surface 103 of the wafer 100 does not contact the abutting surface 37 of the chuck portion 5, and therefore is not sandwiched by the chuck portion 5. Next, in this state, a motor (not shown) connected to the stage 3 is driven to rotate the stage 3. The center of gravity G of the chuck portion 5 is located on the outer side in the radial direction of the platform 3 from the central axis of rotation C and is lower than the central axis of rotation C. Therefore, the centrifugal force generated by the rotation is applied in the direction R2 of Fig. 9. When the rotation speed reaches a certain level or more, the chuck portion 5 is rotated in the R2 direction around the rotation center axis C as shown in FIG. 10 due to the centrifugal force, and the contact surface 37 contacts the end surface 103 of the wafer 100 and is pressed. In this state, the wafer 100 is sandwiched between the chuck portions 5, and thus is fixed to the chuck portion 5. When the rotation speed of the stage 3 is lowered from the state shown in Fig. 10, the centrifugal force generated in the R2 direction is weakened, and when the rotation speed is equal to or lower than a certain rotation speed, the contact surface 37 is separated from the wafer 100 and released. The above is an explanation of the operation when the chuck mechanism 1 clamps the wafer 100.

As described above, according to the present embodiment, the center of gravity G of the chuck portion 5 is located on the outer side and the lower side of the central axis of rotation C. Under this configuration, the smaller the centrifugal force generated by the rotation of the stage 3, the chuck portion 5 is rotated toward the direction away from the wafer 100, and the larger the centrifugal force, the chuck portion 5 is rotated toward the wafer 100.

In this embodiment, the wafer 3 is surely released from the wafer 100 at a certain speed or lower, and the wafer 100 is surely sandwiched at a certain level or more. This mechanism can specify only the relationship between the central axis C of rotation and the center of gravity G, without requiring a spring or a weight, etc., in a simple configuration. When the structure is simple, the chuck portion 5 can be formed by using a resin or a complicated member without using a spring or a complicated member, and thus the corrosion resistance can be improved.

According to the present embodiment, the meandering portion 45 bent to the outside of the chuck body 31 is provided to the lower end 36 of the chuck body 31, whereby the center of gravity G of the chuck portion 5 is located outside and below the center axis of rotation C. Side position. In this embodiment, the structure of the chuck portion 5 is simple, and if the structure is simple, the clip portion 5 can be formed by using a resin injection molding or the like without using a spring or a complicated member, and thus the corrosion resistance can be improved.

According to the present embodiment, the chuck portion 5 includes a long hole 47 that penetrates the lower side of the rotation center hole 43 of the chuck body 31 in the radial direction of the stage 3, and a guide of a round bar shape that is provided to penetrate the long hole 47. Rod 9. The long hole 47 is provided in sliding contact with the guide rod 9 in the circumferential direction of the stage 3, and the diameter (height h) in the up and down direction is larger than the path length DL of the guide rod. In this embodiment, the rotational moment generated by the through shaft 59 due to the rotation of the platform 3 can be relieved by the side of the guide rod 9 contacting the long hole 47, so that the chuck mechanism 1 can be prevented from rotating due to the rotation moment when the stage 3 is rotated. And deformation.

According to this embodiment, the chuck body 31, the wafer holding portion 33, and the meandering portion 45 are integrally formed. In this embodiment, the chuck portion 5 can be manufactured by integral molding such as resin molding, and the corrosion resistance can be improved.

According to the present embodiment, the end surface holding portion 41 is provided from the chuck body 31 and has a protruding portion that abuts against the end surface 103 of the wafer 100, and is provided along the platform 3. A drain 39 provided in the radial direction. In this embodiment, the abutting surface 37 is in contact with the end surface 103 of the wafer 100, so that it can be surely clamped. When the wafer 3 is rotated while being rotated, the cleaning liquid is discharged from the drain 39 by the centrifugal force, and the cleaning liquid can be prevented from remaining between the end surface holding portion 41 and the end surface of the wafer 100 to contaminate the wafer 100. .

According to the present embodiment, the lower holding portion 35 is a tapered portion that is inclined upward from the inner side in the radial direction of the stage 3, and supports the surface 105 of the wafer 100. In this embodiment, when the rotational speed of the stage 3 is below a certain value and the chuck portion 5 is rotated in a direction away from the wafer 100, the lower surface 105 of the wafer 100 can be brought into contact with the upper surface of the lower holding portion 35. The angle is reduced to prevent damage to the wafer 100 during contact.

According to this embodiment, the collet 5 can be composed of polyvinyl chloride or polyetheretherketone. In this embodiment, the chuck portion 5 can be formed of a material that is lightweight, inexpensive, and highly resistant to corrosion, and the corrosion resistance of the chuck mechanism 1 can be improved.

The present invention has been described above with reference to the embodiments, but the present invention is not limited to the embodiments described above. It is a matter of course that various modifications and improvements can be made by those skilled in the art within the scope of the technical idea of the present invention. These modifications and improvements are also included in the scope of the present invention.

Claims (13)

 A chuck mechanism for holding a wafer in a leaflet type, comprising: a disk-shaped platform that can be rotated in a plane direction; and three or more chucking heads are equally disposed on a circumference around a rotation axis of the platform, Surrounding the end surface of the wafer in such a manner as to be rotatable in the radial direction of the platform; and a holding portion disposed on the platform to rotatably hold the collet head, wherein the center of gravity of the collet head is located The central axis of rotation is further to the outside of the radial direction of the platform and to the lower side than the central axis of rotation.    The chuck mechanism of claim 1, wherein the chuck head comprises: a chuck body having a rod shape, the end surface held by the retaining portion as an upper end facing upward; the wafer holding portion The lower holding portion and the end surface holding portion are disposed at an upper end of the chuck body and have a supporting surface contacting and supporting the lower surface of the wafer, the end surface clamping portion having contact and holding the wafer a retaining surface of the end surface; the rotating central hole is formed in the collet body perpendicular to the radial direction of the platform and the axial direction of the collet body; and a meandering portion is disposed at a lower end of the collet body at the platform The radial direction is bent to the outside of the chuck body, wherein the retaining portion includes a through shaft that is disposed through the rotating center hole, and a base portion that is disposed on the platform to fix the through shaft.    The chuck mechanism of claim 2, further comprising: a long hole, which is disposed in a radial direction of the platform than a lower end of the rotating center hole of the chuck body; and a guide of a round bar shape a lead rod is disposed through the long hole, wherein the long hole is disposed in sliding contact with the guiding rod in a circumferential direction of the platform, and a diameter of the vertical direction is longer than a diameter of the guiding rod .    The chuck mechanism of claim 2, wherein the chuck body, the wafer holding portion, and the meandering portion are integrally formed.    The collet mechanism according to any one of claims 2 to 4, wherein the end face clamping portion includes: a protruding portion that is erected from the collet body and has an abutting end surface of the wafer The abutting surface; and the drain groove are disposed on the protruding portion along the radial direction of the platform.    The chuck mechanism according to any one of claims 2 to 4, wherein the lower holding portion includes a tapered portion that is inclined upward from an inner side in a radial direction of the platform toward an outer side, wherein the supporting surface is the tapered portion The top.    The chuck mechanism according to any one of claims 1 to 4, wherein the chuck head is made of polyvinyl chloride or polyetheretherketone.    A chucking head is a chuck mechanism for holding a wafer by a blade type, comprising: a chuck body having a rod shape; and a rotating central hole formed in a direction perpendicular to an axial direction of the chuck body In the chuck body, the wafer holding portion has an end portion disposed on one side of the chuck body, and faces a clamping direction perpendicular to the chuck body and the rotating center hole, in the clip In the inward direction, the center of gravity is located outside the direction in which the wafer is sandwiched by the center hole, and in the axial direction of the chuck body, the center of gravity is located opposite to the wafer holding portion with respect to the center hole of the rotation side.    The chuck mechanism of claim 3, wherein the chuck body, the wafer holding portion, and the meandering portion are integrally formed.    The collet mechanism according to claim 9, wherein the end face clamping portion includes: a protruding portion that is erected from the collet body and has an abutting surface that abuts an end surface of the wafer; The drain groove is provided in the protruding portion along the radial direction of the platform.    The chuck mechanism according to claim 9, wherein the lower holding portion includes a tapered portion that is inclined upward from an inner side in a radial direction of the platform toward an outer side, wherein the support surface is an upper surface of the tapered portion.    The chuck mechanism according to claim 10, wherein the lower holding portion includes a tapered portion that is inclined upward from an inner side in a radial direction of the platform toward an outer side, wherein the support surface is an upper surface of the tapered portion.    The collet mechanism according to any one of claims 9 to 12, wherein the collet head is made of polyvinyl chloride or polyetheretherketone.