JP4235313B2 - Double-side polishing machine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention is used for, for example, double-side polishing of a silicon wafer.Double-side polishing machineAbout.
[0002]
[Prior art]
A silicon wafer, which is a material of a semiconductor device, is finished in a mirror state by being lapped after being cut out from a silicon single crystal and then subjected to further polishing. In the past, this mirror surface finishing was performed only on the device forming surface. However, in a large-diameter wafer having a diameter of more than 8 inches such as 12 inches, the back surface on which the device is not formed is required to have a finishing comparable to the mirror surface. As a result, polishing has become necessary on both sides.
[0003]
For double-side polishing of a silicon wafer, a planetary gear type double-side polishing apparatus is usually used. The schematic structure of this double-side polishing apparatus will be described with reference to FIGS. FIG. 13 is a view taken along line AA in FIG.
[0004]
The planetary gear type double-side polishing apparatus includes a pair of upper and lower rotating surface plates 1 and 2, a plurality of carriers 3, 3. A sun gear 4 disposed at the center of rotation between the panels 1 and 2 and an annular internal gear 5 disposed at the outer periphery between the rotating surface plates 1 and 2 are provided.
[0005]
The upper rotating surface plate 1 can be moved up and down, and the rotation direction is opposite to the rotation direction of the lower rotating surface plate 2. A polishing cloth (not shown) is attached to each facing surface of the rotary surface plates 1 and 2. Each carrier 3 has an eccentric circular accommodation hole, and a circular workpiece 6 made of a silicon wafer is held in the accommodation hole. The sun gear 4 and the internal gear 5 mesh with the plurality of carriers 3 from the inside and the outside, and are normally driven to rotate in the same direction as the lower rotating surface plate 2.
[0006]
In the polishing operation, a plurality of carriers 3, 3... Are set on the lower rotating surface plate 2 with the upper rotating surface plate 1 raised, and then the workpiece 6 is transferred into each carrier 3. , Supplied on the rotating surface plate 2. When the supply of the workpieces 6, 6... Is finished, the upper rotating platen 1 is lowered, and the workpieces 6, 6. In this state, the rotary surface plates 1, 2, the sun gear 4, and the internal gear 5 are rotationally driven while supplying abrasive liquid between the rotary surface plates 1 and 2.
[0007]
By this rotational drive, the plurality of carriers 3, 3... Revolve around the sun gear 4 while rotating between the rotating surface plates 1 and 2 rotating in the opposite direction. As a result, the plurality of workpieces 6, 6.
[0008]
[Problems to be solved by the invention]
Even in such a silicon wafer double-side polishing operation, automation of the operation is an important technical issue. For this automation, for example, it is necessary to automatically supply a plurality of workpieces 6, 6... On the lower rotating surface plate 2. For this automatic supply, conventionally, the lower rotating surface plate 2 is fixed, and the workpieces 6, 6,... Are sucked into a plurality of carriers 3, 3,. It is conceivable to carry them simultaneously or sequentially.
[0009]
However, when the workpiece 6 is a 12-inch silicon wafer, the rotating surface plates 1 and 2 and the surrounding internal gear 5 and the like increase in size as the workpiece 6 becomes larger. The positions of the carriers 3, 3... Placed on the rotating surface plate 2 become inaccurate. On the other hand, the tolerance between the inner diameter of the carrier 3 and the outer diameter of the workpiece 6 is more strictly limited. For these reasons, in the method of mechanically transporting the workpieces 6, 6... In the carriers 3, 3... On the rotating surface plate 2, there is a risk that the workpiece 6 will not be completely fitted in the carrier 3. For this reason, monitoring and reworking by workers is necessary, and it has been found that this is a major factor that hinders complete automation.
[0010]
  The object of the present invention is to enable fully automatic feeding onto a lower rotating surface plate even in the case of a large-diameter workpiece such as a 12-inch silicon wafer.Double-side polishing machineIs to provide.
[0011]
(Delete)
[0012]
[Means for Solving the Problems]
  To achieve the above objective,The double-side polishing apparatus of the present invention is a polishing apparatus that simultaneously double-side polishes a plurality of workpieces held on a plurality of carriers by rotating a plurality of carriers holding a workpiece to be polished at least between upper and lower rotating surface plates. A main body, a uniting mechanism for combining the work with the carrier outside the polishing apparatus main body, and a supply mechanism for supplying the work combined with the carrier outside the polishing apparatus main body onto the lower surface plate in the combined stateThe uniting mechanism includes a carrier storage unit that supports a plurality of carriers stacked in a vertical direction at predetermined intervals, a carrier transport unit that transports carriers one by one from the carrier storage unit to the carrier alignment unit, and a carrier position. A workpiece first conveying unit that conveys the workpiece to the carrier alignment unit in order to combine the workpiece with the carrier aligned by the aligning unit, and the supply mechanism has a suction head at the tip of the swivel / lift arm And a second swivel / lift-type work second transport section that sucks the carrier and the work combined with the work with the suction head and transports the work onto the lower surface plate from the combining mechanism.AndThe carrier transport unit includes a table in which a carrier is transferred from the carrier storage unit onto one end by lowering of the carrier storage unit, and the other end serves as a carrier alignment unit serving as a uniting part of the carrier and the workpiece. A carrier mechanism that transports the carrier transferred at one end to the carrier positioning unit, and the carrier positioning unit is provided above and below the lifting plate and has a lifting plate having positioning pins on the upper surface. A workpiece cradle that is driven up and down together with the plate, and in the state where the lift plate is raised, the positioning pin penetrates the table and projects onto the table to position the carrier on the table. The workpiece is placed in a state of being positioned on the carrier through the workpiece receiving hole, and the lifting plate is lowered to the initial position from this state, so that the workpiece is received. Work on the platform is inserted into the workpiece accommodating hole of the carrier positioned on the table is intended to combine both the united states.
[0013]
  Conventionally, there has been a problem of a decrease in carrier position accuracy caused by placing a plurality of carriers on a lower surface plate in advance. Of the present inventionDouble-side polishing machineThen, when supplying the work on the lower surface plate, the carrier is not put on the lower surface plate in advance, and before the work is supplied, that is, the wafer and the carrier are combined on the outside of the polishing apparatus main body,UnionIn operation,The carrier is transported to the carrier alignment unit one by one by the carrier transport unit from the carrier storage unit that supports a plurality of carriers stacked in the vertical direction at predetermined intervals. The workpieces are sequentially combined with the carrier thus formed by the first workpiece transfer unit. After the uniting operation, the workpiece combined with the carrier is sequentially transferred from the uniting mechanism onto the lower surface plate by the second workpiece transfer unit. thisTherefore, even in the case of a 12-inch silicon wafer, the union operation is reliably performed, and monitoring and reworking by an operator is not necessary, so that the workpiece can be completely automatically supplied onto the lower surface plate.
[0014]
  Both sides of the present inventionPolishing equipmentThen, the workpiece after polishing may be discharged from the lower surface plate separately from the carrier, or may be discharged from the lower surface plate while being combined with the carrier, but the latter is preferable from the viewpoint of simplifying the structure of the apparatus. . That is, a supply mechanism for supplying a work and a carrier onto the lower surface plate by discharging the polished work from the lower surface plate while being combined with the carrier can be used as a discharge mechanism for the work and the carrier.That is, the work 2nd conveyance part in a supply mechanism can serve also as the discharge mechanism which discharges | emits the workpiece | work which finished grinding on the lower surface plate to the said union | meshing mechanism in the union | combining state with a carrier. Moreover, the workpiece | work 1st conveyance part in a coalescing mechanism can serve as the separation mechanism which isolate | separates the workpiece | work discharged | emitted to the coalescing mechanism in the united state with a carrier from a carrier, It can also serve as a return mechanism for returning the carrier separated from the workpiece to the carrier storage unit.
[0015]
  About coalescence mechanismIs even easierIs it possible to perform a reliable uniting operation with a single device configuration?The carrier transport unit is a table in which the carrier is transferred from the carrier storage unit onto one end by lowering of the carrier storage unit, and the other end is a carrier alignment unit that doubles as a united part of the carrier and the workpiece. A carrier mechanism for transporting the carrier transferred at one end on the table to the carrier alignment unit, wherein the carrier alignment unit includes a lifting plate having positioning pins on the upper surface, and an upper side of the lifting plate. And a workpiece cradle that is driven up and down together with the lifting plate, and in the state that the lifting plate is raised, the positioning pin penetrates the table and projects onto the table to position the carrier on the table. The cradle is positioned on the carrier through the work receiving hole of the carrier, and the work is placed thereon. From this state, the lifting plate is lowered to the initial position. More, it is intended to combine the work on the workpiece cradle is inserted into the workpiece accommodating hole carriers both in the united states.
[0016]
For supplying workpieces on the lower platen, the workpiece is transported to multiple positions on the surface plate with the lower platen fixed in the past. Since the accuracy also decreases, it is preferable that the workpieces be sequentially conveyed to a fixed position by performing an indexing operation for rotating the lower surface plate by a predetermined angle.
[0017]
In this case, it is desirable to perform the indexing operation of the lower surface plate so that relative movement with respect to the lower surface plate of the carrier already placed on the lower surface plate does not occur. The carrier already placed on the lower surface plate is in a floating state on the lower surface plate and is very easy to move. When this carrier moves, the work position goes wrong and its lower surface is inadvertently polished. By preventing relative movement of the carrier during the indexing operation, this problem is solved.
[0018]
In the case where the polishing apparatus main body rotates a plurality of carriers, which will be described later, in a fixed position, there is no integral type internal gear that meshes with the plurality of carriers from the outside, so an indexing operation without relative movement of the carriers is easy. is there.
[0019]
The work supply to a fixed position by combining with the indexing operation is not only when the work is combined with the carrier and supplied to the polishing apparatus main body, but also when the work is combined with a plurality of carriers set in advance in the polishing apparatus main body. Can be applied, and the same effect can be obtained by the application.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. 1 is a plan view of a double-side polishing apparatus according to an embodiment of the present invention, FIG. 2 is a plan view of a double-side polishing apparatus used in the double-side polishing apparatus, and FIG. 3 is a plan view of a lower rotating surface plate. 4 is a longitudinal sectional view of the lower rotating surface plate, FIG. 5 is a longitudinal sectional view of the upper rotating surface plate, FIG. 6 is a plan view of the combining mechanism, FIG. 7 is a side view of the combining mechanism, and FIG. FIG. 9 is a plan view and a side view of the supply mechanism, FIG. 10 is a plan view and a side view of the brush storage unit, and FIG. 11 is a plan view and a side view of the dresser storage unit.
[0021]
The double-side polishing equipment shown in FIG. 1 is used for automatic double-side polishing of silicon wafers. This double-side polishing equipment includes a plurality of double-side polishing apparatuses 100, 100... Arranged side by side, a loader / unloader apparatus 200 arranged on the side thereof, and a basket transport apparatus 300 connecting them. .
[0022]
The loader / unloader apparatus 200 includes a suction-type workpiece transfer robot 210. The workpiece transfer robot 210 takes out the workpiece 400 made of silicon wafer from the carry-in basket 220 and transfers it to the transfer basket 310 in the basket transfer device 300. Further, the polished workpiece 400 is taken out from the transfer basket 310 and transferred to the carry-out basket 230.
[0023]
The transport basket 310 accommodates a plurality of workpieces 400, 400,.
[0024]
The basket transfer apparatus 300 includes a plurality of lifting mechanisms 320, 320,... Corresponding to the plurality of double-side polishing apparatuses 100, 100,. It is selectively conveyed from the apparatus 200 to a plurality of lifting mechanisms 320, 320. Further, the transport basket 310 containing the polished workpiece 400 is transported from the lifting mechanisms 320, 320... To the loader / unloader device 200.
[0025]
The lifting mechanism 320 receives the plurality of workpieces 400, 400,... Accommodated in the transport basket 310 to the corresponding double-side polishing apparatus 100, and accommodates the transport basket 310 in the accommodation alignment pitch of the workpieces 400, 400,. Raise and lower at a pitch corresponding to.
[0026]
As shown in FIG. 2, the double-side polishing apparatus 100 has a polishing apparatus main body 110, a first workpiece transfer unit 120, a workpiece alignment unit 130, a carrier storage unit 140, a carrier transfer unit 150, and a carrier alignment on a common base frame. The unit 160, the second workpiece transfer unit 170, the brush storage unit 180, and the dresser storage unit 190 are mounted.
[0027]
The polishing apparatus main body 110 is provided on the lower rotary platen 111, the upper rotary platen 112 concentrically combined thereon (see FIG. 5), and the center of the lower rotary platen 111. Center gear 113 and a plurality of rotation means 114 provided around the lower rotating surface plate 111.
[0028]
The lower rotating surface plate 111 supports a plurality of carriers 500, 500... Around the center gear 113. The carrier 500 is a circular external gear, and has a circular accommodation hole 510 at a position eccentric with respect to the center thereof, and the silicon wafer as the workpiece 400 is accommodated in the accommodation hole 510.
[0029]
As shown in FIGS. 3 and 4, the rotating surface plate 111 is a disk having an opening at the center, and is attached on the disk of a rotation support member 111 a having a cavity at the center. The rotation support member 111a is rotationally driven in a predetermined direction by a driving mechanism (not shown), thereby rotating the rotating surface plate 111 in a predetermined direction and stopping at the origin position. The origin position is a reference stop position of the rotating surface plate 111 before and after polishing, particularly after polishing.
[0030]
The rotating surface plate 111 is provided with a plurality of nozzles 111b, 111b,... Penetrating the rotating surface plate 111 in the thickness direction. The plurality of nozzles 111b, 111b,... Are provided so as to correspond to the workpiece 400 in the carrier 500 when the rotary platen 111 stops at the origin position. These nozzles 111b, 111b,... Are ducts 111c, 111c,... Provided between the rotary platen 111 and the disk part of the rotation support member 111a, and vertical holes 111d, 111d provided in the shaft part of the rotation support member 111a. .. and connected to a suction device (not shown) through a rotary joint 111e attached to the shaft.
[0031]
As shown in FIG. 5, the upper rotating surface plate 112 is an annular plate body, and is attached to the lower surface of the disk portion of the rotation support member 112a. The rotation support member 112a is driven up and down and rotated by a drive mechanism (not shown). Thereby, the rotating surface plate 112 moves up and down on the lower rotating surface plate 111, rotates in the opposite direction to the rotating surface plate 111, and stops at the origin position.
[0032]
Like the rotary platen 111, the rotary platen 112 is provided with a plurality of nozzles 112b, 112b... Penetrating the rotary platen 112 in the thickness direction. The plurality of nozzles 112b, 112b,... Are provided so as to correspond to the workpiece 400 in the carrier 500 when the rotating surface plate 112 stops at the origin position, like the nozzles 111b, 111b,. These nozzles 112b, 112b,... Are connected to a fluid supply device (not shown) via conduits 112c, 112c,..., Horizontal holes and vertical holes provided in the disk portion of the rotation support member 112a.
[0033]
The center gear 113 of the polishing apparatus main body 110 is positioned by a circular recess 111f provided on the upper surface of the central portion of the rotating surface plate 111, and meshes with a plurality of carriers 500, 500,. The drive shaft of the center gear 113 passes through an opening 111g provided at the center of the rotating surface plate 111 and a cavity 111h provided at the center of the rotation support member 111a, and projects below the rotation support member 111a. It is connected with the drive device that is not. As a result, the center gear 113 is driven to rotate independently of the lower rotating surface plate 111.
[0034]
The plurality of rotation means 114, 114... Are outside the plurality of carriers 500, 500... Arranged on the rotating surface plate 111, and each rotation means 114 has two vertical gears meshing with the corresponding carrier 500. 114a, 114a. The gears 114a and 114a are rotationally driven in the same direction in synchronization by a driving device (not shown), thereby causing the corresponding carrier 500 to rotate in a fixed position in cooperation with the center gear 113. The gears 114a and 114a also release the carrier 500 before and after polishing by moving up and down between an operating position engaging with the carrier 500 and a retracted position below the operating position.
[0035]
The above is the structure of the polishing apparatus main body 110. Below, each of the 1st work conveyance part 120, work position alignment part 130, carrier storage part 140, carrier conveyance part 150, carrier position alignment part 160, the 2nd work conveyance part 170, brush storage part 180, and dresser storage part 190 The structure will be described in order.
[0036]
The uniting mechanism that unites the workpiece 400 with the carrier 500 outside the polishing apparatus main body 110 includes the first workpiece conveyance unit 120, the workpiece alignment unit 130, the carrier conveyance unit 150, and the carrier alignment unit 160. The first workpiece transfer unit 120 also serves as a loading mechanism that loads the workpiece 400 into the double-side polishing apparatus 100. Further, the supply mechanism for supplying the workpiece 400 and the carrier 500 combined on the outside of the polishing apparatus main body 110 onto the rotating surface plate 111 on the lower side of the polishing apparatus main body 110 is constituted by the second work conveying section 170. The second workpiece transfer unit 170 also serves as a discharge mechanism that discharges the workpiece 400 that has been polished on the lower rotating surface plate 111 to the outside of the polishing apparatus main body 110 while being combined with the carrier 500.
[0037]
The first workpiece transfer unit 120 includes a workpiece loading mechanism that loads the workpiece 400 from the conveyance basket 310 stopped by the lifting mechanism 320 of the basket conveyance device 300 into the double-side polishing apparatus 100, and the workpiece alignment unit 130 to the carrier alignment unit 160. It also serves as a workpiece transfer mechanism for transferring the workpiece 400. As shown in FIGS. 6 and 7, the first workpiece transfer unit 120 drives the suction arm 121 in the horizontal direction and the vertical direction, and the suction arm 121 that horizontally sucks the workpiece 400 from above at the lower surface of the tip. And a drive mechanism 122 composed of an articulated robot.
[0038]
As shown in FIGS. 6 and 7, the workpiece alignment unit 130 includes a pair of gripping members 131 and 131 that clamp the workpiece 400 from both sides, and a drive mechanism 132 that drives the gripping members 131 and 131 to contact and separate. Yes. Each opposing surface of the gripping members 131, 131 is an arc surface corresponding to the outer peripheral surface of the workpiece 400.
[0039]
The first workpiece transfer unit 120 places the workpiece 400 from the transfer basket 310 stopped by the lifting mechanism 320 of the basket transfer device 300 on a table (not shown) of the workpiece alignment unit 130. The workpiece 400 placed on the table is positioned between the gripping members 131 and 131 separated on both sides. In this state, the gripping members 131 and 131 move inward, and the workpiece 400 is moved to a fixed position by clamping the workpiece 400 from both sides. Thereby, the workpiece 400 is positioned.
[0040]
The positioned workpiece 400 is again attracted by the first workpiece conveyance unit 120 and conveyed to a carrier alignment unit 160 described later.
[0041]
As shown in FIGS. 6 and 7, the carrier storage unit 140 includes a plurality of support plates 141, 141,... That support a plurality of carriers 500, 500,. Yes. The support shaft 142 that supports the support plates 141, 141,... Is supported by a guide sleeve 143 that is vertically fixed so as to be movable in the axial direction, and by a ball screw type drive mechanism 144 attached to the guide sleeve 143 in the axial direction. Driven. As a result, the support plates 141, 141... Intermittently descend from the upper limit position at a predetermined pitch, and the carriers 500, 500... Are sequentially placed on the support base 151 of the carrier transport unit 150 described later. For this mounting, each support plate 141 supports the carrier 500 in a state where a part of the carrier 500 protrudes to both sides.
[0042]
The carrier transport unit 150 transports the carrier 500 from the carrier storage unit 140 to the carrier alignment unit 160. As shown in FIG. 6, the carrier transport unit 150 includes a support base 151 that horizontally supports the carrier 500 and a pair of transport mechanisms 152 and 152 provided on both sides of the support base 151.
[0043]
The support base 151 has notches 151a through which the support plates 141, 141,... Of the carrier storage unit 140 pass, at the end on the carrier storage unit 140 side. A circular large-diameter opening 151b through which a later-described carrier 162 of the carrier alignment unit 160, which will be described later, passes, and a plurality of positioning pins 163, 163, are inserted at the end of the support 151 in the carrier alignment unit 160 side. A plurality of small diameter openings 151c, 151c are provided.
[0044]
As shown in FIG. 8, the transport mechanism 152 on each side drives a horizontal guide rail 152a attached to the side surface of the support base 151, a slider 152b movably supported by the guide rail 152a, and the slider 152b. And a drive mechanism 152c. The drive mechanism 152c drives the belt with a motor to drive the slider 152b connected to the belt straight along the guide rail 152a. The slider 152b has a pin-shaped engaging portion 152d protruding upward. The engaging portion 152d engages with the side portion of the outer peripheral tooth of the carrier 500 placed on the support base 151.
[0045]
That is, the carrier 500 is placed on one end portion of the support base 151 from the carrier storage portion 140 in a state where the sliders 152b and 152b of the transport mechanisms 152 and 152 on both sides are positioned on both sides of the end portion of the support base 151. The engaging portions 152d and 152b of the sliders 152b and 152b on both sides engage with both sides of the outer peripheral teeth of the carrier 500. In this state, the sliders 152b and 152b move synchronously to both sides of the other end of the support base 151, whereby the carrier 500 is transported to the other end of the support base 151 and sent to the carrier alignment section 160.
[0046]
The carrier alignment unit 160 is combined with the other end of the support base 151. As shown in FIGS. 6 and 7, the carrier alignment unit 160 includes a lift plate 161 for positioning the carrier 500, a workpiece And a circular pedestal 162 on which 400 is placed. The elevating plate 161 has a plurality of positioning pins 163 and 163. The cradle 162 is positioned above the elevating plate 161 and is driven up and down together with the elevating plate 161 by the lower drive mechanism 164.
[0047]
That is, the carrier alignment unit 160 sets the initial position when the upper surface of the upper receiving table 162 is substantially flush with the upper surface of the support table 151 of the carrier transport unit 150. Accordingly, at this initial position, the plurality of positioning pins 163, 163, are positioned below the support plate 151. In this state, when the carrier 500 is conveyed onto the other end of the support base 151, the accommodation hole 510 of the carrier 500 matches the large-diameter opening 151 b of the support base 151. When the conveyance is finished, the elevating plate 161 and the cradle 162 are raised. Due to this rise, the plurality of positioning pins 163, 163... Pass through the small diameter openings 151 c and 151 c provided in the other end of the support base 151, and the plurality of positioning pins provided in the carrier 500 on the other end. Are inserted into the small-diameter holes 520 and 520. As a result, the carrier 500 is positioned on the other end of the support base 151.
[0048]
At this time, the cradle 162 rises to above the carrier 500 through the large-diameter opening 151 b of the support pedestal 151 and the accommodation hole 510 of the carrier 500. On the raised cradle 162, the workpiece 400 aligned by the workpiece alignment unit 130 is sucked and conveyed by the first workpiece conveyance unit 120 and placed. When this placement is finished, the elevating plate 161 and the cradle 162 are lowered to the initial position. As a result, the workpiece 400 on the receiving table 162 is inserted into the accommodation hole 510 of the carrier 500 positioned on the other end of the support table 151, and the workpiece 400 is combined with the carrier 500 so as to be separable.
[0049]
The second workpiece transfer unit 170 of the double-side polishing apparatus 100 transfers the combined work 400 and carrier 500 to the polishing apparatus main body 110. As shown in FIG. 9, the second workpiece transfer unit 170 rotates the suction head 172 attached to the tip of the horizontal arm 171 and the arm 171 in the horizontal plane around the base and moves up and down in the vertical direction. And a drive mechanism 173 for driving.
[0050]
The suction head 172 is equipped with a plurality of suction pads 174, 174,... On the lower surface in order to horizontally hold the workpiece 400 and the carrier 500 combined therewith. The workpiece 400 and the carrier 500 combined by the carrier alignment unit 160 are conveyed onto the rotating surface plate 111 on the lower side of the polishing apparatus main body 110 by the combination of the turning and raising / lowering of the suction head 172 accompanying this. The suction head 172 is provided with a plurality of escape holes 172a, 172a. In order to avoid interference with a plurality of support pins 193, 193.
[0051]
As shown in FIG. 10, the brush storage unit 180 has a support base 181 that supports a plurality of brushes 600, 600,... Stacked in the thickness direction, and a plurality of brushes 600, 600,. Holding members 182 and 182. A support shaft 183 that supports the support base 181 is supported by a guide sleeve 184 that is vertically fixed so as to be movable in the axial direction, and is driven in the axial direction by a ball screw type driving mechanism 185 attached to the guide sleeve 184.
[0052]
Each brush 600 is an external gear having a shape corresponding to the carrier 500, and is used for cleaning an abrasive cloth attached to the facing surfaces of the rotary surface plates 111 and 112. For this cleaning, a plurality of brush portions 610, 610,... Are provided on the upper and lower surfaces of the brush 600. The reason why the brush portions 610, 610,... Are arranged in a distributed manner is to enable the suction conveyance. The upper surface side brush portions 610, 610,... And the lower surface side brush portions are displaced in the circumferential direction so as not to interfere with each other when the brushes 600, 600,. The holding members 182 and 182 hold the brushes 600, 600,... By engaging the outer peripheral teeth of the brushes 600, 600,.
[0053]
As shown in FIG. 11, the dresser storage unit 190 holds a support base 191 that supports a plurality of dressers 700, 700,... Stacked in the thickness direction, and the dressers 700, 700,. A plurality of holding members 192 and 192 are provided. The support base 191 includes a plurality of support pins 193, 193, the outer diameter of which increases stepwise from the top to the bottom in order to support the dressers 700, 700,.・ Support. A support shaft 194 that supports the support base 191 is supported by a guide sleeve 195 that is vertically fixed so as to be movable in the axial direction, and is driven in the axial direction by a ball screw type drive mechanism 196 attached to the guide sleeve 195.
[0054]
Each dresser 700 is an external gear having a shape corresponding to the carrier 500. On the upper and lower surfaces of the outer peripheral portion of the dresser 700, grinding portions 710, 710,... Made of a large number of diamond pellets and the like are attached in order to condition the surface of the polishing cloth attached to the opposing surfaces of the rotating surface plates 111, 112. ing. Since the grinding parts 710, 710,... Are limitedly provided on the outer peripheral part of the dresser 700, the dresser 700 can also be sucked and conveyed.
[0055]
The second workpiece transport unit 170 that sucks and transports the workpiece 400 and the carrier 500 combined by the carrier alignment unit 160 to the polishing apparatus main body 110 also serves as a transport unit that sucks and transports the brush 600 and the dresser 700 to the polishing apparatus main body 110. . For this reason, the brush storage unit 180 and the dresser storage unit 190 are disposed directly below the turning arc of the suction head 172 of the second workpiece transfer unit 170.
[0056]
Next, an automatic double-side polishing operation for a silicon wafer using the double-side polishing equipment will be described.
[0057]
The double-side polishing apparatus 100 carries a plurality of workpieces 400, 400... By the first workpiece transfer unit 120 from the transfer basket 310 stopped by the lifting mechanism 320 of the basket transfer device 300. Specifically, the workpieces 400, 400... In the transfer basket 310 are sucked in order from the top by the suction arm 121 of the first workpiece transfer unit 120 and placed on a table (not shown) of the workpiece alignment unit 130. As the workpieces 400, 400,... Are taken out, the transport basket 310 is driven upward by one pitch by the lifting mechanism 320.
[0058]
When the workpiece 400 is placed on a table (not shown) of the workpiece alignment unit 130, the gripping members 131 and 131 approach each other. Thereby, the workpiece 400 is positioned at a predetermined position.
[0059]
In parallel with the loading of the workpieces 400, 400... In the transfer basket 310, the carriers 500, 500 .. in the carrier storage unit 140 are transferred from one end of the support base 151 to the other end by the carrier transfer unit 150. And sent to the carrier alignment unit 160. The carrier 500 sent to the carrier alignment unit 160 is positioned at a predetermined position by raising the elevating plate 161 and the cradle 162 and raising the plurality of positioning pins 163, 163.
[0060]
When the elevating plate 161 and the cradle 162 are raised, the work 400 is transported from the work position aligning unit 130 onto the cradle 162 by the suction arm 121 of the first work transport unit 120. Here, since the suction arm 121 of the first workpiece transfer unit 120 only sucks the workpiece 400 aligned by the workpiece alignment unit 130 from above and conveys it onto the cradle 162, the workpiece alignment unit 130. If the workpiece 400 is in the predetermined position, the workpiece 400 is also positioned at the predetermined position on the cradle 162, so that the workpiece 400 is accurately positioned with respect to the receiving hole 510 of the carrier 500 positioned below the workpiece 400. Will be positioned.
[0061]
Then, when the elevating plate 161 and the cradle 162 are lowered to the initial position, the workpiece 400 is reliably inserted into the accommodation hole 510 of the carrier 500.
[0062]
In this way, by combining the workpiece 400 and the carrier 500 positioned on the outside of the polishing apparatus main body 110 into a combined state that is separable on the outside of the polishing apparatus main body 110, the combining operation is reliably performed. Therefore, monitoring and reworking by workers is not necessary. Moreover, since the workpiece 400 is conveyed to the workpiece alignment unit 130 by the suction-type simple first workpiece conveyance unit 120, it is not necessary to provide a complicated guide mechanism or the like in the first workpiece conveyance unit 120. Configuration is also simplified.
[0063]
When the workpiece 400 and the carrier 500 are merged at the workpiece alignment unit 130, the workpiece 400 and the carrier 500 remain on the rotating surface plate 111 below the polishing apparatus main body 110 while being merged by the second workpiece transfer unit 170. It is transported to a fixed position. At this time, in the polishing apparatus main body 110, the upper rotating surface plate 112 is raised, and the plurality of rotation means 114, 114,.
[0064]
By repeatedly carrying the workpiece 400 and the carrier 500 to a fixed position on the rotating surface plate 111 while performing an indexing operation for rotating the lower rotating surface plate 11 by a predetermined angle, a plurality of workpieces 400, 400. Is supplied on the lower rotating surface plate 111. The second workpiece transport unit 170 that sequentially transports the workpiece 400 and the carrier 500 to a fixed position on the rotating surface plate 111 has a simple structure as compared with that which distributes and transports the workpiece 400 and the carrier 500 to a plurality of positions on the rotating surface plate 111. High conveyance accuracy. At this time, since the plurality of rotation means 114 are lowered, they do not mesh with the carriers 500, 500,. On the other hand, the center gear 113 meshes with the carriers 500, 500... On the rotating surface plate 111, but the rotating surface plate 111 prevents the carriers 500, 500. It is driven in synchronization with the rotation of 111. For these reasons, the workpieces 400, 400,... Supplied on the lower rotating surface plate 111 do not inadvertently move on the rotating surface plate 111 even when the rotating surface plate 111 is indexed.
[0065]
When the conveyance of the workpiece 400 and the carrier 500 onto the lower rotating platen 111 is completed, the plurality of rotating means 114, 114,... Rise to a fixed position and the upper rotating platen 112 descends. Thereby, the plurality of workpieces 400, 400... On the rotating surface plate 111 are sandwiched from above and below by the polishing cloth. In this state, the rotating surface plates 111 and 112 are rotated in the reverse direction while supplying abrasive liquid between the rotating surface plates 111 and 112. Further, the center gear 113 and the rotation means 114, 114,... Meshing with the carriers 500, 500,. As a result, the carriers 500, 500,... Continue to rotate at a fixed position between the rotating surface plates 111, 112, and the workpieces 400, 400,. Thereby, both surfaces of each work 400 are polished.
[0066]
The polishing apparatus main body 110 that rotates the carriers 500, 500,... Between the rotating surface plates 111, 112 at a fixed position does not require a large internal gear as compared with the conventional planetary gear type with revolution. As a result, the apparatus price can be reduced while maintaining high polishing accuracy. Further, by making the rotation means 114, 114... Liftable, the indexing operation of the rotating surface plate 111 when supplying the workpieces 400, 400... Can be performed simply by rotating the rotating surface plate 111 and the center gear 113. Done. If the center gear 113 is liftable like the rotation means 114, 114..., The indexing operation can be performed by rotating only the rotating surface plate 111.
[0067]
When the double-side polishing of the workpieces 400, 400,... Is finished, the upper and lower rotary surface plates 111, 112 stop at the origin position. After the stop, the rotary platen 112 is raised while injecting fluid such as water from a plurality of nozzles 112b, 112b,... Provided on the upper rotary platen 112. Further, the plurality of nozzles 111b, 111b,... Provided on the lower rotating surface plate 111 are sucked.
[0068]
At this time, since the upper and lower rotary surface plates 111 and 112 are stopped at the origin position, the nozzles 112b, 112b,... Face the upper surfaces of the workpieces 400, 400,. 400, 400... For this reason, the workpieces 400, 400,... Receive pressure and downward suction due to fluid injection from the upper side, and when the upper rotary platen 112 is raised, the workpieces 400, 400. Retained. For this reason, drying of the workpieces 400, 400... Is prevented. Moreover, since the workpiece holding force is a fluid pressure for both the pressing force from above and the suction force downward, there is no risk of damaging the workpieces 400, 400.
[0069]
The downward suction by the plurality of nozzles 111b, 111b,... Provided on the lower rotating surface plate 111 is short in order to prevent the workpieces 400, 400,. is there. Even if the suction by the nozzles 111b, 111b,... Is omitted, the pressure from above by the fluid from the nozzles 112b, 112b,. There is almost no danger of moving to the side.
[0070]
When the upper rotating surface plate 112 rises to a fixed position, the workpieces 400, 400... Are transferred from the lower rotating surface plate 111 to the work position aligning unit 130 by the second work transport unit 170. Transport in union. Even during the discharging, an indexing operation for rotating the lower rotating surface plate 11 by a predetermined angle is performed.
[0071]
The workpiece 400 and the carrier 500 conveyed to the workpiece alignment unit 130 are separated by an operation reverse to that performed when the workpiece alignment unit 130 is combined. The workpiece 400 separated from the carrier 500 is stored in the transfer basket 310 by the first workpiece transfer unit 120, and the remaining carrier 500 is stored in the carrier storage unit 140 by the carrier transfer unit 150.
[0072]
As described above, the double-side polishing apparatus 400, 400,... Uses the second workpiece transfer unit 170, the workpiece alignment unit 130, the first workpiece transfer unit 120, and the like used for supplying the workpiece. It is discharged out of 100 and is transported to the loader / unloader device 200 by the transport basket 310.
[0073]
When one double-side polishing operation is completed, before starting the next double-side polishing, the plurality of brushes 600, 600,... Stored in the brush storage unit 180 are rotated downward by the second work transfer unit 170. It is sequentially conveyed onto the surface plate 111. This conveyance is also performed in the same manner as the conveyance of the workpiece 400 and the carrier 500, and the rotating surface plate 111 performs an indexing operation. Further, in the brush storage unit 180, each time the brush 600 is carried out, the support base 181 is raised by one pitch, and the uppermost brush 600 is moved to the carrying-out position.
[0074]
When the transfer of the brushes 600, 600,... Onto the lower rotating platen 111 is finished, the upper rotating platen 112 is lowered, and the brushes 600, 600,. In this state, while rotating the rotating surface plates 111, 112 in the reverse direction, the center gear 113 and the rotating means 114, 114,... Meshing with the brushes 600, 600,. Thus, the upper and lower abrasive cloths are cleaned by the brushes 600, 600.
[0075]
When cleaning of the upper and lower polishing cloths is finished, the upper rotating platen 112 is raised, and the second workpiece transfer unit 170 transfers the brushes 600, 600... From the lower rotating platen 111 to the brush storage unit 180. To do. Even when the brush is discharged, an indexing operation for rotating the lower rotating surface plate 11 by a predetermined angle is performed.
[0076]
When discharge of the brushes 600, 600,... Is finished, double-side polishing of the next workpiece 400, 400,.
[0077]
After the completion of several double-side polishing operations, before starting the next double-side polishing, the plurality of dressers 700, 700,... Stored in the dresser storage unit 180 are moved downward by the second work transfer unit 170. It is sequentially conveyed onto the rotating surface plate 111. This conveyance is also performed in the same manner as the conveyance of the brush 600. The rotary surface plate 111 performs an indexing operation. In the dresser storage unit 190, the support base 191 is raised by one pitch every time the dresser 700 is carried out, and the uppermost dresser is moved. 700 is moved to the unloading position.
[0078]
When the dressers 700, 700,... Are transferred onto the lower rotating surface plate 111, the upper rotating surface plate 112 is lowered, and the dressers 700, 700,. In this state, while rotating the rotating surface plates 111 and 112 in the reverse direction, the center gear 113 and the rotating means 114, 114... Meshing with the dressers 700, 700. As a result, the upper and lower polishing cloths are conditioned by the dressers 700, 700,.
[0079]
When the dressing of the upper and lower polishing cloths by the dressers 700, 700,... Is finished, the upper rotary platen 112 is raised, and the second work transfer unit 170 moves from the lower rotary platen 111 to the dresser storage unit 180. The dressers 700, 700,. Even when the dresser is discharged, an indexing operation for rotating the lower rotating surface plate 11 by a predetermined angle is performed.
[0080]
When the dressers 700, 700,... Are discharged, the polishing cloth is cleaned with the brushes 600, 600,.
[0081]
As described above, the double-side polishing apparatus 100 includes the brush storage unit 180 that stores the brushes 600, 600... And the second work transfer unit 170 that transports the brushes 600, 600. Since the polishing cloth can be automatically brushed, frequent brushing such as every polishing is possible. Therefore, the quality of polishing can be improved. In addition, the second workpiece transport unit 170 that transports the brushes 600, 600,... Onto the lower rotating surface plate 111 transports the workpieces 400, 400,. Since this is also used, the device configuration is simple.
[0082]
The double-side polishing apparatus 100 includes a dresser storage unit 190 that stores the dressers 700, 700,... And a second work transfer unit 170 that transports the dressers 700, 700,. Since the dressing of the polishing cloth can be performed automatically, frequent dressing such as once in several polishings is possible, and even dressing for each polishing is possible. Therefore, the quality of polishing can be further improved. In addition, the second work transport unit 170 that transports the dressers 700, 700,... Transports the work 400, 400,. Simple.
[0083]
In the above embodiment, the double-side polishing apparatus 100 performs polishing of a silicon wafer, but can also be applied to lapping of a silicon wafer, and can also be applied to polishing and lapping other than a silicon wafer.
[0084]
Further, the polishing apparatus main body 110 of the double-side polishing apparatus 100 performs only the rotation of the carriers 500, 500... At a fixed position between the rotating surface plates 111, 112, but is a planetary gear system that combines rotation and revolution. There may be.
[0085]
【The invention's effect】
  As explained above, the present inventionDouble-side polishing machineBefore supplying the workpiece onto the lower surface plate, the workpiece is combined with the carrier so that it can be separated from the carrier, and then the workpiece is combined with the carrier and then supplied onto the lower surface plate to obtain 12 inch silicon. Even in the case of a wafer, the uniting operation can be performed reliably. This eliminates the need for monitoring and reworking by workers, and enables fully automatic supply of workpieces on the lower surface plate, enabling full-automatic double-side polishing even for 12-inch silicon wafers. The polishing cost is greatly reduced.
[Brief description of the drawings]
FIG. 1 is a plan view of a double-side polishing facility according to an embodiment of the present invention.
FIG. 2 is a plan view of a double-side polishing apparatus used in the double-side polishing equipment.
FIG. 3 is a plan view of a lower rotating surface plate.
FIG. 4 is a longitudinal sectional view of a lower rotating surface plate.
FIG. 5 is a longitudinal sectional view of an upper rotating surface plate.
FIG. 6 is a plan view of a uniting mechanism that unites a workpiece and a carrier.
FIG. 7 is a side view of the uniting mechanism.
FIG. 8 is a side view of the carrier transport mechanism in the uniting mechanism.
FIGS. 9A and 9B are a plan view and a side view of a supply mechanism that supplies a workpiece onto a lower surface plate. FIGS.
FIGS. 10A and 10B are a plan view and a side view of a brush storage unit. FIGS.
FIGS. 11A and 11B are a plan view and a side view of a dresser storage unit. FIGS.
FIG. 12 is a schematic configuration diagram of a double-side polishing apparatus.
13 is a view taken along the line AA in FIG.
[Explanation of symbols]
100 Double-side polishing machine
110 Polishing machine body
111, 112 rotating surface plate
113 Center gear
114 Rotating means
120 1st work conveyance part
130 Workpiece alignment section
140 Carrier storage
150 Carrier transport unit
160 Carrier alignment section
170 Second workpiece transfer section
180 Brush compartment
190 Dresser storage
200 Loader / Unloader Device
300 Basket transport device
400 work
500 carriers
600 brushes
700 dressers

Claims (4)

A polishing apparatus main body that simultaneously polishes a plurality of workpieces held on a plurality of carriers on both sides simultaneously by rotating a plurality of carriers holding a work to be polished between upper and lower rotating surface plates, and an outer side of the polishing apparatus main body And a uniting mechanism for uniting the workpiece with the carrier and a supply mechanism for supplying the workpiece united with the carrier outside the polishing apparatus main body onto the lower surface plate in the united state ,
The union mechanism includes a carrier storage unit that supports a plurality of carriers stacked in a vertical direction at predetermined intervals, a carrier transport unit that transports one carrier at a time from the carrier storage unit to the carrier alignment unit, and a carrier alignment unit. A workpiece first transport unit that transports the workpiece to the carrier alignment unit in order to combine the workpiece with the carrier aligned in the united state,
The supply mechanism has a suction head at the tip of the swivel / lifting arm, and a suction / lifting work piece that sucks the carrier and the work combined with the suction head and transports it from the combining mechanism onto the lower surface plate. have a 2 transport unit,
The carrier transport unit includes a table in which a carrier is transferred from the carrier storage unit onto one end by lowering of the carrier storage unit, and the other end serves as a carrier alignment unit serving as a uniting part of the carrier and the workpiece. A carrier mechanism that transports the carrier transferred at one end to the carrier positioning unit,
The carrier alignment unit includes a lifting plate having a positioning pin on the upper surface, and a work cradle that is provided above the lifting plate and is driven up and down together with the lifting plate. The workpiece penetrates the table and projects onto the table to position the carrier on the table, and the workpiece cradle is placed on the carrier through the workpiece receiving hole of the carrier. Is lowered to the initial position, whereby the workpiece on the workpiece cradle is inserted into the workpiece receiving hole of the carrier positioned on the table, and the both are combined into a combined state . 2. The double-side polishing apparatus according to claim 1, wherein the work second transport unit in the supply mechanism also serves as a discharge mechanism for discharging the work, which has been polished on the lower surface plate, to the combining mechanism while being combined with a carrier . 2. The double-side polishing apparatus according to claim 1, wherein the work first transport unit in the coalescence mechanism also serves as a separation mechanism that separates the work discharged from the carrier in the coalescence state with the carrier from the carrier . The double-side polishing apparatus according to claim 3, wherein the carrier transport unit in the uniting mechanism also serves as a return mechanism that returns the carrier separated from the work in the work first transport unit to the carrier storage unit .

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