JP2004148425A - Both-sided polishing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To polish a workpiece uniformly and suppress an increase in size of a device efficiently. <P>SOLUTION: A carrier 12 holding a wafer W is clamped with upper and lower polishing plates 14, 16 and the wafer W is polished from both upper and lower sides by rotational drive of these plates 14, 16. The carrier 12 comprising an external gear wheel is connected with an upper end of a main drive shaft 50 arranged on the same axial line as the center of rotation of the plates 14, 16 through an eccentric joint 52. The eccentric joint 52 is equipped with a connection shaft 52b eccentric to the main drive shaft 50, and the carrier 12 is rotatably connected with this connection shaft 52b at its center. An internal gear wheel 60 is arranged on a circle concentric with the main drive shaft 50 outside the carrier 12, and a portion of the carrier 12 is engaged with the internal gear wheel 60. The main drive shaft 50 is arranged in the radial direction of rotation inwardly of an outer periphery of the carrier 12 in a plan view. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double-side polishing apparatus for polishing a workpiece held by a carrier using a surface plate having polishing surfaces disposed on both upper and lower sides thereof.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, a double-side polishing apparatus that sandwiches a work (eg, a semiconductor wafer or the like) held by a carrier from both upper and lower sides with a pair of polishing plates and polishes the wafer while rotating each polishing plate about a vertical axis in this state is generally used. Are known.
[0003]
In this type of polishing apparatus, if the wafer is in contact with the polishing platen at a fixed position, it is considered that unevenness in polishing occurs on the wafer due to a difference in speed between the inside and outside of the platen in the radial direction.
[0004]
Therefore, in order to prevent the occurrence of such polishing unevenness, a drive type double-side polishing apparatus using a planetary gear mechanism as schematically shown in FIG. 6 has been conventionally proposed.
[0005]
This apparatus rotates an external gear 100 (external gear) and an internal gear 102 (internal gear), which are sun gears, at different speeds in the same direction, thereby forming a disk-shaped disk gear corresponding to a planetary gear holding a wafer W. The carrier 104 is revolved while rotating, and is relatively moved while sandwiching the wafer W from above and below by a disk-shaped polishing platen 106 (hereinafter abbreviated as a platen) disposed on both upper and lower sides of the carrier 104. It is configured to be polished.
[0006]
The external gear 100 and the polishing platen 106 have a center of rotation on the same axis as shown in the figure, and each carrier 104 holds a plurality of wafers W around its rotation axis (center). It is configured. That is, when each carrier 104 rotates and revolves as described above by the operation of the external gear 100 and the internal gear 102, each wafer W swings (that is, the polishing platen 106) as shown by the locus of the wafer center in FIG. The wafer W is configured to make a circular motion around the external gear with accompanying rotation (displacement in the rotation radius direction) and rotation (rotation). Position).
[0007]
[Problems to be solved by the invention]
According to the conventional apparatus, as described above, the wafer W is rotated (rotated) while swinging in the rotation radius direction of the polishing platen 106, so that the occurrence of polishing unevenness can be satisfactorily avoided, and the wafer W can be made uniform. It is thought that it can be polished.
[0008]
However, on the other hand, there are the following problems. That is, when the size of the wafer W to be processed increases, the size of the carrier 104 for holding the wafer W inevitably increases, and the carrier 104 revolves around the external gear 100 while meshing its teeth along the outer periphery thereof. In the conventional configuration, a larger space is required around the external gear 100, and there is a problem that the entire device becomes larger. Such an increase in the size of the apparatus is not only disadvantageous in reducing the cost of the apparatus, saving energy, saving space, and the like, but it is also conceivable that vibrations are generated due to insufficient strength and adversely affect the polishing accuracy. Therefore, it is necessary to improve this point.
[0009]
Further, the inner surface polishing apparatus as described above is generally configured to give a constant movement to the work, but depending on the type of the work, the polishing is performed only by swinging or only by circular movement. It may be advantageous to do so. Therefore, it is more preferable that the movement given to the workpiece during polishing can be changed according to the type of the workpiece and the like.
[0010]
The present invention has been made in view of the above-described problems, and an object of the present invention is to polish a work uniformly, and to effectively suppress an increase in the size of an apparatus. Thus, it is possible to change the operation mode of the work at the time of polishing.
[0011]
[Means for Solving the Problems]
In order to solve the above problems, the present invention sandwiches a work held by a carrier from both front and back sides by a pair of polishing platens, and in this state, rotates each of the polishing platens around an axis in their arrangement direction, In a double-side polishing apparatus for polishing a workpiece by moving a carrier in a direction parallel to a polishing surface of a polishing table, an axis parallel to a rotation axis of the polishing table and eccentric by a predetermined distance with respect to the rotation axis. Rotating the carrier around, and a carrier driving means for circularly moving the carrier around the rotation axis of the polishing platen, wherein the rotation axis of the polishing platen is located radially inward of the outer circumference of the carrier in the rotation radial direction. The carrier and the polishing platen are provided so as to perform the above.
[0012]
According to this double-side polishing apparatus, the work held by the carrier is rotated (rotated) and oscillated (of the polishing platen) by the carrier making a circular motion around the rotation axis of the polishing platen while rotating (rotating). (Displacement in the direction of the radius of rotation) while making a circular motion about the rotation axis of the polishing table. Therefore, the same movement as that of a conventional device of this type can be given to the work. In addition, since the center of the circular motion of the carrier is provided inside the carrier, the carrier is revolved around the external gear, that is, as compared with the conventional device in which the center of the circular motion of the carrier is provided outside the carrier. The radius of the circular motion of the carrier is small, and the space required for the motion is small. Therefore, as compared with the conventional apparatus, the apparatus can be made compact while polishing a work of the same size, and an increase in the size of the apparatus can be effectively suppressed.
[0013]
In the above apparatus, a drive spindle is provided on the same axis as the rotation axis of the polishing platen, and the drive spindle has an eccentric axis which is eccentric by the predetermined distance with respect to the center axis of the drive spindle. It is preferable that the carrier is rotatably connected so that the carrier driving means is configured such that the carrier makes the circular motion with the rotation of the driving main shaft.
[0014]
With this configuration, the above-described circular motion can be imparted to the carrier with a simpler configuration than a device using a conventional planetary gear mechanism, and the center of the circular motion can be provided inside the carrier.
[0015]
In this case, it is preferable to include an interlocking unit that rotates the carrier around the eccentric axis in conjunction with the rotation of the drive main shaft. For example, as the interlocking means, an external gear provided on the carrier and an internal gear meshing with the external gear from the outside and arranged concentrically with the rotation axis of the polishing platen can be provided.
[0016]
According to this configuration, the carrier makes a circular motion with the rotation of the driving main shaft, and at this time, the carrier rotates (self-rotates) around its central axis by meshing between the internal gear and the carrier (external gear). That is, by driving the drive spindle, the carrier can be given the circular motion and the carrier can be rotated on its own, resulting in a rational configuration.
[0017]
In the double-side polishing apparatus, the carrier driving unit includes a spindle driving mechanism that rotationally drives the driving spindle and an internal gear driving mechanism that rotationally drives the internal gear around its central axis. It is preferable that drive control means capable of changing the drive state of the drive mechanism be provided.
[0018]
According to this configuration, the movement given to the workpiece during polishing is changed according to the type of the workpiece or the like, so that more appropriate polishing processing according to the type of the workpiece can be performed.
[0019]
For example, the drive control means includes: a first drive state in which only the internal gear is rotationally driven while the drive main shaft is stopped; and a drive in which the drive main shaft and the internal gear are rotationally driven in the same direction. A second driving state in which the internal gear is driven at a speed obtained by multiplying the rotational speed of the driving main shaft by the ratio of the number of teeth to the driving main shaft, and driving the driving main shaft and the internal gear in the same direction at a rotational speed other than the second driving state It is preferable that the driving state of each of the driving mechanisms can be changed to a third driving state in which only the driving main shaft is rotationally driven with the internal gear stopped.
[0020]
In other words, according to the first driving state, the work performs only a circular motion around the rotation axis (eccentric axis) of the carrier, and according to the second driving state, the work is moved to a substantially specific position around the rotation axis of the polishing platen. In the third driving state, the work makes a circular motion around the rotation axis of the polishing platen with rotation (rotation) and rocking. . Therefore, by appropriately changing the first to third driving states, it is possible to perform an optimal polishing operation according to the type of the work and the like with a common device.
[0021]
Although the carrier may be configured to hold one work, it is preferable that a plurality of works can be held in order to efficiently perform the polishing operation. In this case, the eccentric shaft is preferably used. A plurality of work holding portions may be provided at equal intervals around the periphery of the work.
[0022]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described with reference to the drawings.
[0023]
1 and 2 show an example of a double-side polishing apparatus according to the present invention in a perspective view and a front view (partial sectional view). The double-side polishing apparatus 10 (hereinafter, abbreviated as the polishing apparatus 10) shown in these drawings holds a wafer W by, for example, a polishing apparatus that polishes a silicon wafer W (hereinafter, a wafer W) as a material of a semiconductor chip as a work. The carrier 12 includes a carrier 12, a pair of polishing plates 14, 16 disposed vertically above and below the carrier 12, and driving means for these.
[0024]
The carrier 12 is formed in a disk shape and has an external gear provided on an outer periphery thereof. The carrier 12 holds the wafer W and also serves as a member for driving the carrier 12.
[0025]
The carrier 12 is formed with a plurality of through holes 12a (work holding portions) penetrating in the vertical direction for holding the wafer W. In this embodiment, four through holes 12a around the center axis of the carrier 12 are formed. Are provided at equal intervals.
[0026]
The carrier 12 is connected to a drive spindle 50 described later via an eccentric joint 52, and is configured to be driven as the drive spindle 50 rotates. This point will be described later in detail.
[0027]
The polishing platen 14 (referred to as a lower platen 14) disposed below the carrier 12 of the pair of polishing platens 14 and 16 includes a disk-shaped platen body 20 having an opening 20 a at the center, and a main body. And a holder 22 for supporting the substrate 20 from below to prevent its deformation, and having a geared motor 26 fixed to a device frame (not shown) around its central axis (around the central axis of the platen body 20). It is configured to be rotationally driven. That is, the holder 22 is provided integrally with a vertically extending sleeve 22a at the lower end thereof. The holder 22a is supported by a device frame (not shown) via a bearing or the like, and the sleeve 22a A gear 24 is integrally attached to the lower end, and the gear 24 meshes with a gear 28 mounted on an output shaft of the geared motor 26. Thus, the lower platen 14 is driven to rotate by the geared motor 26 via the gears 28, 24 and the like.
[0028]
The polishing platen 16 (referred to as an upper platen 16) disposed above the carrier 12 has basically the same configuration as the lower platen 14, and has a platen body 30 having an opening 30b at the center. And a holder 32 for supporting the main body 30 from above.
[0029]
The upper surface plate 16 is configured to be driven to rotate around its central axis (around the central axis of the surface plate main body 30) and to be driven up and down with respect to the lower surface plate 14. That is, a vertically extending support shaft 34 is integrally provided on the upper portion of the holder 32, and this support shaft 34 is a distal end (lower end) of an operating shaft 37 of a pressurizing mechanism 36 provided on an unshown apparatus frame. Are connected so as to be relatively rotatable. Further, a gear 38 is mounted on the support shaft 34, the gear 38 is rotatably held by the apparatus frame, and can be moved relative to the support shaft 34 in the vertical direction, and the relative rotation is prevented. A gear 42 is connected to the output shaft of a geared motor 40 mounted on the apparatus frame, and is engaged with the gear 38. The working position shown in FIG. 2 with the advance and retreat of the moving shaft 37 by the pressurizing mechanism 36, that is, the position where the platen body 30 comes into contact with the wafer W held by the carrier 12, and the retreat position ( (The position shown in FIG. 1), the upper platen 16 is driven up and down, and the geared motor 40 is driven to rotate the upper platen 16 via gears 42, 38 and the like.
[0030]
The rotation center of the upper stool 16 and the rotation center of the lower stool 14 are provided on the same axis, and the stool main body 30 of the upper stool 16 and the stool main body 20 of the lower stool 14 are different from each other. Both have the same shape.
[0031]
A polishing liquid feed pipe 44 is connected to a part of the support shaft 34 of the upper surface plate 16. During the polishing process, the liquid feed pipe 44 and a liquid feed passage (not shown) in the holder 32 are provided. The polishing liquid is supplied from the platen body 30 to the wafer W through the base. The liquid supply pipe 44 is connected to the support shaft 34 via a joint 43 rotatably fitted to the support shaft 34 as shown in FIG. 2, and the polishing liquid is supplied between the joint 43 and the support shaft 34. While being stored in the toroidal liquid storage portion formed at the end, the liquid is introduced into the liquid supply passage through an introduction hole formed in the support shaft 34. Thus, the polishing liquid can be introduced into the support shaft 34 that is driven to rotate.
[0032]
In the lower platen 14, a drive spindle 50 for driving the carrier 12 is inserted into the sleeve 22a of the holder 22, as shown in FIGS. The drive spindle 50 is supported in the sleeve 22a via a bearing 51, whereby the drive spindle 50 is rotatably supported on the same axis as the rotation centers of the surface plates 14, 16.
[0033]
The lower end of the drive spindle 50 is connected to the output shaft of a geared motor 53 fixed to the device frame, while the upper end is connected to the carrier 12 via an eccentric joint 52. As shown in FIG. 3, the eccentric joint 52 includes a link 52a (link member) fixed to the drive main shaft 50, a connection shaft 52b (eccentric shaft) erected on the link 52a, and a bearing mounted on the connection shaft 52b. 52c, which is rotatably mounted via 52c. The carrier fixing portion 52d is inserted and fixed in an opening formed in the center of the carrier 12, so that the eccentric joint 52 The carrier 12 is connected to the upper end of the drive spindle 50.
[0034]
The connecting shaft 52b of the eccentric joint 52 is offset by a predetermined dimension h (eccentric distance) with respect to the axis of the driving main shaft 50, so that when the driving main shaft 50 rotates, the dimension h is set as a radius of rotation and the carrier 12 is rotated. Are configured to make a circular motion (turn) around the drive main shaft.
[0035]
Outside the carrier 12 (radially outside), an internal gear 60 is provided concentrically with the drive main shaft 50. As shown in FIG. Are engaged.
[0036]
The internal gear 60 is fixed to a holder 62, and is rotatably supported by the apparatus frame via the holder 62. The holder 62 has an annular external gear structure (not shown in detail), and a gear 66 mounted on an output shaft of a geared motor 64 fixed to the apparatus frame meshes with the holder 62 from outside. ing. Thus, the internal gear 60 is configured to be rotationally driven by the geared motor 64 via the holder 62. That is, in this embodiment, the internal gear drive mechanism of the present invention is constituted by the holder 62 and the geared motor 64 and the like, and the main shaft drive mechanism of the present invention is constituted by the geared motor 53 and the like.
[0037]
The polishing apparatus 10 includes a well-known CPU that executes a logical operation, a ROM that previously stores various programs for controlling the CPU, a RAM that temporarily stores various data during operation of the apparatus, and the like. Each of the motors 26, 40, 53, 64 and the actuator of the pressurizing mechanism 36 are electrically connected to the control device 70. The control unit 70 controls the driving of the motors 26 and the like so as to execute a predetermined polishing operation in accordance with a program stored in the CPU.
[0038]
In the polishing apparatus 10, as described below, it is possible to give three different movements to the wafer W being polished, and to operate a switching means (not shown) provided in the control device 70. The control device 70 is configured to control the driving of the motor 53 and the like in order to execute the operation selected by operating the switching means.
[0039]
Next, an operation of polishing the wafer W by the polishing apparatus 10 will be described.
[0040]
First, the wafer W is set in each of the through holes 12a of the carrier 12 in a state where the upper platen 16 is set at the raised retracted position, and then the upper platen 16 is lowered and set at the working position. When the upper platen 16 is set at the working position in this manner, the wafer W held by the carrier 12 is predetermined by the respective platen bodies 20 and 30 of the platens 14 and 16 from both upper and lower sides as shown in FIG. The state is sandwiched by the pressing force.
[0041]
Then, the polishing liquid is supplied to the wafer W through the liquid feed pipe 44, and the respective platens 14, 16 are driven to rotate, whereby the wafer W is simultaneously polished from both the upper and lower sides. At this time, the lower platen 14 is rotated clockwise and the upper platen 16 is rotated counterclockwise at the same speed, whereby the polishing resistance (frictional force) acting on the upper and lower sides of the wafer W is offset, and the wafer W is rotated. Damage or the like caused by the peripheral edge of W being pressed against the through hole 12a is prevented.
[0042]
During the polishing operation, the control device 70 controls the motor 53 so that the drive state of the carrier 12 and the internal gear 60 is any one of the following first to third drive states. Is controlled, whereby one of three different movements (movements) is given to the wafer W.
[0043]
<First driving state>
In the first drive state, only the internal gear 60 is driven to rotate clockwise at a predetermined rotation speed with the drive spindle 50 stopped.
[0044]
According to such a first driving state, since the carrier 12 and the internal gear 60 are in mesh with each other, the rotation of the internal gear 60 causes the carrier 12 to rotate only around its central axis (the connection shaft 52b). . Therefore, as schematically shown in FIG. 5A, the wafer W held by the carrier 12 repeats a circular motion around the center axis of the carrier 12. FIG. 5A shows the movement of the wafer W by a locus at the center thereof (the same applies to FIGS. 5B and 5C).
[0045]
<Second drive state>
In the second drive state, the drive main shaft 50 is driven clockwise at a predetermined rotational speed, while the internal gear 60 has a specific ratio to the drive main shaft 50, specifically, the number of teeth of the carrier 12 and the internal gear 60. The motor is driven clockwise at a speed obtained by multiplying the rotation speed of the drive spindle 50 by the ratio.
[0046]
According to such a second driving state, the carrier 12 does not roll along the internal gear 60 (without rotation (rotation)), but circularly moves (turns) around the driving main shaft. Therefore, as shown in FIG. 5B, the wafer W held by the carrier 12 repeats a circular motion at a substantially specific position around the rotation axes of the surface plates 14 and 15. That is, the displacement of the surface plates 14 and 15 in the rotational radius direction is repeated (oscillated) substantially at the fixed position.
[0047]
<Third drive state>
In the third drive state, the drive spindle 50 is driven clockwise at a predetermined rotation speed, while the internal gear 60 is stopped or driven at a speed other than the rotation speed of the internal gear 60 in the second drive state.
[0048]
According to such a third driving state, the carrier 12 circularly moves (turns) around the drive main shaft, and rolls along the internal gear 60 so that the carrier 12 rotates around its central axis (around the connection shaft 52b) ( (Rotation). Therefore, as shown in FIG. 5C, the wafer W held by the carrier 12 moves circularly around the rotation axes of the platens 14 and 15 while rotating (rotating) and swinging. .
[0049]
The above-described first to third driving states are switched according to the operation of the switching means (not shown) as described above, and are automatically performed before the polishing operation by the polishing apparatus 10 is started or manually performed by an operator. It is switched according to the operation.
[0050]
When the polishing process of the wafer W elapses, for example, for a certain period of time while the platens 14, 16 and the carrier 12 are driven in this way, the platens 14, 16 and the carrier 12 stop, and the carrier 12 is reversed in the reverse procedure. Is removed from the wafer W, whereby a series of polishing operations by the polishing apparatus 10 is completed.
[0051]
According to the polishing apparatus 10 described above, if the carrier 12 and the internal gear 60 are in the third driving state during the polishing operation of the wafer W, the wafer W rotates (rotates) and swings as described above. A circular motion is made around the rotation axes of the platens 14 and 15 (see FIG. 5C). Therefore, the polishing process can be performed while giving the same movement (see FIG. 7) to the wafer W as in the conventional apparatus of this type, and the wafer W can be polished at a level comparable to the conventional apparatus.
[0052]
Moreover, according to the polishing apparatus 10, since the center of the circular motion (the drive main shaft 50) of the carrier 12 is disposed inside the carrier 12 as shown in FIG. 5, the carrier revolves around the external gear ( In this configuration, the radius of the circular motion of the carrier 12 can be reduced as compared with the conventional device in which the carrier is configured to perform the circular motion, that is, the center of the circular motion of the carrier is provided outside the carrier. Therefore, while polishing the same size wafer W, the entire apparatus can be configured more compactly than the conventional apparatus, and the enlargement of the polishing apparatus 10 can be effectively suppressed.
[0053]
Therefore, according to the polishing apparatus 10, there is an effect that the size of the apparatus can be effectively suppressed while the wafer W is polished uniformly as in the conventional apparatus.
[0054]
In the polishing apparatus 10, three different types of movements (operations) of the wafer W are performed in accordance with the switching of the driving state (the first driving state to the third driving state) of the carrier 12 and the internal gear 60 as described above. Since the wafer W can be polished while selectively giving the wafer W, an optimal movement can be selected and given to the wafer W according to, for example, the type of the wafer W and the type of the polishing liquid. Therefore, there is an effect that the wafer W can be more efficiently and appropriately polished as compared with the conventional apparatus which can give only a single movement to the wafer W.
[0055]
The polishing apparatus 10 described above is an example of a double-side polishing apparatus according to the present invention, and the specific configuration thereof can be appropriately changed without departing from the gist of the present invention. Various configurations can be adopted.
[0056]
{Circle around (1)} In the above embodiment, the external gear is provided on the carrier 12 and the internal gear 60 meshing with the external gear from the outside is provided as the interlocking means of the present invention. By mounting a motor and fixing the carrier 12 to the output shaft of the motor as the connecting shaft 52b, the carrier 12 may be rotated by driving the motor.
[0057]
Even with such a configuration, the same movement as the movement of the wafer W in the first to third drive states can be achieved by appropriately controlling the rotational drive of the drive spindle 50 by the geared motor 53 and the rotational drive of the carrier 12 by the motor. It can be given to the wafer W.
[0058]
{Circle around (2)} During the polishing, the movement of the wafer W shown in FIG. 5C, that is, the movement of rotating (spinning) and making a circular motion around the rotation axes of the platens 14 and 15 with the swing is as described above. This can also be achieved by driving the drive spindle 50 with the internal gear 60 stopped. Therefore, when the movement can be dealt with only by the movement of the wafer W, the configuration may be simplified by providing the internal gear 60 fixedly and omitting the geared motor 64 and the like.
[0059]
{Circle around (3)} In the above embodiment, an example is described in which the double-side polishing apparatus of the present invention is applied to, for example, a polishing apparatus for polishing a silicon wafer W (hereinafter, wafer W) as a material of a semiconductor chip. The double-side polishing apparatus is also applicable to, for example, a lapping machine.
[0060]
【The invention's effect】
As described above, in the double-side polishing apparatus of the present invention, the carrier rotates around an axis eccentric from the rotation center of the polishing table, the carrier makes a circular motion around the rotation axis of the polishing table, The rotation axis of the workpiece is located radially inward of the outer circumference of the carrier, so that the work is rotated (rotated) and oscillated (displacement of the polishing platen in the radius direction of rotation) as in the conventional apparatus. This makes it possible to make a circular motion around the rotation axis of the polishing platen, and to make the radius of the circular motion of the carrier smaller than that of the conventional apparatus. Therefore, the work can be polished uniformly at a level comparable to that of the related art, and the size of the apparatus can be effectively suppressed.
[Brief description of the drawings]
FIG. 1 is a schematic perspective view showing an example of a double-side polishing apparatus according to the present invention.
FIG. 2 is a front view (partially sectional view) showing a double-side polishing apparatus according to the present invention.
FIG. 3 is a cross-sectional view showing a carrier supporting portion in the double-side polishing apparatus.
FIG. 4 is a schematic plan view showing a positional relationship among a carrier, a wafer, an internal gear, a driving main shaft, and an eccentric shaft.
5A and 5B are schematic plan views showing the movement of the wafer during wafer polishing (the locus of the center of the wafer). FIG. 5A shows the movement of the wafer in the first driving state, FIG. 5B shows the movement of the wafer in the second driving state, (C) shows the movement of the wafer in the third driving state, respectively).
FIG. 6 is a schematic plan view showing a double-side polishing apparatus using a conventional planetary gear mechanism.
FIG. 7 is a schematic plan view showing movement of a work (trajectory of the center of the work) during a polishing process of a conventional apparatus.
[Explanation of symbols]
10 Double-side polishing machine
12 career
12a through hole
14 Polishing surface plate (lower surface plate)
16 Polishing surface plate (Upper surface plate)
26,40,53,64 Geared motor
50 drive spindle
52 Eccentric joint
52a link
52b Connecting shaft (eccentric shaft)
52c bearing
52d carrier fixing part
60 internal gear
W wafer

Claims (7)

The work held by the carrier is sandwiched from both sides by a pair of polishing plates, and in this state, each polishing platen is rotated around an axis in a direction in which the polishing plates are arranged, and the carrier is moved in a direction parallel to the polishing surface of the polishing platen. In a double-side polishing apparatus for polishing the work by moving to
A carrier that rotates the carrier about a vertical axis that is parallel to the rotation axis of the polishing platen and is eccentric by a predetermined distance with respect to the rotation axis, and that makes the carrier circularly move around the rotation axis of the polishing platen. A double-side polishing apparatus, comprising: a driving unit; and the carrier and the polishing platen are provided such that a rotation axis of the polishing platen is positioned radially inward of an outer periphery of the carrier in a rotation radial direction. The double-side polishing apparatus according to claim 1,
A drive spindle disposed on the same axis as a rotation axis of the polishing platen, wherein the carrier is rotatable around an eccentric axis that is eccentric by the predetermined distance with respect to a center axis of the drive spindle. The double-side polishing apparatus is characterized in that the carrier driving means is configured such that the carrier makes the circular motion with the rotation of the driving main shaft by being connected. The double-side polishing apparatus according to claim 2,
A double-side polishing apparatus comprising an interlocking means for rotating the carrier about the eccentric axis in conjunction with the rotation of the drive spindle. The double-side polishing apparatus according to claim 3,
Wherein the interlocking means comprises: an external gear provided on the carrier; and an internal gear meshed with the external gear from outside and arranged concentrically with a rotation axis of the polishing platen. apparatus. The double-side polishing apparatus according to claim 4,
The carrier driving means has a main shaft driving mechanism for rotating the driving main shaft and an internal gear driving mechanism for driving the internal gear to rotate around the center axis thereof, and a drive capable of changing a driving state of each of the driving mechanisms. A double-side polishing apparatus comprising a control unit. The double-side polishing apparatus according to claim 5,
The drive control means includes: a first drive state in which only the internal gear is rotationally driven while the drive main shaft is stopped; and a drive in which the drive main shaft and the internal gear are rotationally driven in the same direction. A second driving state in which the internal gear is driven at a speed obtained by multiplying the rotational speed of the driving main shaft by a gear ratio, and a driving state in which the driving main shaft and the internal gear are driven in the same direction and at a rotation speed other than the second driving state. A double-side polishing apparatus characterized in that the driving state of each of the driving mechanisms can be changed to a third driving state in which only the driving main shaft is rotationally driven with the internal gear stopped. The internal polishing apparatus according to claim 1, wherein the carrier has a plurality of work holding portions around the connection shaft.

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