JP2007044786A - Flattening device and method of semiconductor substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flattening device of an in-line system having high productivity for plane-grinding and polishing the rear face of a substrate to make an extremely thin semiconductor substrate of 20 to 50 μm. <P>SOLUTION: This flattening device 100 is provided with a substrate storing stage 101 at the outside of a room, and a substrate edge holding type first carrying stage 103, a grinding stage 104 having four stages of a substrate loading/unloading stage S1, a rough grinding stage S2, a middle finishing grinding stage S3 and a precision grinding stage S4 arranged on a concentric circle on an index rotary table 2 in a clockwise direction, a pair of substrate temporary placing stands 105a and 105b, a polishing stage 106 capable of simultaneously polishing two sheets of substrates, a substrate edge holding type second carrying stage 108, and a washing stage 109 at the inside of a room. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a planarization apparatus and a method for planarizing a semiconductor substrate, which are used for thinning and planarizing a substrate by grinding and polishing a back surface of a semiconductor substrate in a pretreatment process of an IC substrate.

  As a method for grinding a semiconductor substrate, one index rotation divided into a load / unload stage A, a first rough grinding stage B, a second finish grinding stage C and a polishing stage D Surface grinding / polishing apparatus in which four sets of substrate holder tables capable of vacuum chucking five small-diameter semiconductor substrates on a table are arranged at equal intervals on the same circumference with respect to the axis of the index rotating table , The loading of the semiconductor substrate by the transfer robot at each stage accompanying the 90 ° rotation of the index rotation table with respect to each substrate holder table, and roughing of the back surface of the substrate by the rough grinding flat grindstone It is known to sequentially perform grinding processing, finish grinding processing of the back surface of the substrate with a finish grinding flat grindstone, mirror polishing with a polishing pad, and unloading with a transfer robot. In this surface grinding / polishing apparatus, the diameters of the coarse grinding flat grindstone, the finish grinding flat grindstone, and the polishing pad are larger than the diameter of the substrate holder table (see, for example, Patent Document 1). ).

  The diameter of the semiconductor substrate is increased to 200 mm (8 inches), and one semiconductor substrate is placed on each of the four sets of substrate holder tables provided in the index rotating table. A flat processing apparatus provided with a diamond-type diamond wheel, a finish grinding cup wheel-type diamond wheel, and a polishing pad has been proposed. As shown in FIGS. 9 and 10, the flat surface processing apparatus 10 is divided into a load / unload stage 17, a rough grinding stage 18, a finish grinding stage 20, and a polishing stage 22. A pair of substrate holder tables 32, 36, 38, and 40 capable of vacuum chucking one semiconductor substrate on one index rotating table 34 are on the same circumference with respect to the axis of the index rotating table 34. The diameters of the rough grinding wheel 46, the finish grinding wheel 54, and the polishing pad 56 are 1 to 1.3 times the diameter of the substrate holder table. (For example, refer to Patent Document 2).

  In the surface grinding / polishing apparatus 10 shown in FIGS. 9 and 10, 26 and 26 are a load port (storage cassette) and an unload port (storage cassette) from the front, and 14 is a cassette storage stage. , 28 is a semiconductor substrate, 12 is a base, 16 is a substrate alignment stage, 23 is a polishing pad cleaning stage, 24 is a cleaning stage, 30 is a ceiling-carrying robot, and 58 is a travel level. , 97 is a transfer robot, 34 is an index rotation table, 37 is a spindle shaft of the index rotation table, 32, 36, 38, 40 are substrate holder tables, 23 is a polishing pad cleaner, 27 Is a polishing pad dressing stage.

  In the process of grinding and polishing the back surface of the semiconductor substrate 28 using the surface grinding / polishing apparatus 10, one semiconductor substrate 28 accommodated in the load port 26 in the cassette accommodation stage 14 is ceiling-mounted. The hand 31 of the suspension robot 30 is sucked and held, and is transported to the substrate alignment stage 16 where the semiconductor substrate 28 is aligned. After alignment, the semiconductor substrate 28 is again sucked and held by the hand 31 of the transfer robot 30 and then transferred onto the vacuum chuck 32 at the load / unload stage 17 position of the index rotation table 34. And sucked and held by the vacuum chuck 32.

  Next, the index rotating table 34 is rotated 90 degrees in the clockwise direction, and the vacuum chuck 32 on which the semiconductor substrate 28 is placed is guided to the position of the vacuum chuck 36 of the first rough grinding stage 18. When the grinding cup wheel type diamond grindstone 46 is rotated and lowered to cut and grind the back surface of the semiconductor substrate, and the semiconductor substrate has a thickness in the vicinity of a desired thickness (for example, 100 to 250 μm, or 30 to 120 μm), rough grinding is performed. The cup wheel type diamond grindstone 46 is raised and moved away from the back surface of the semiconductor substrate.

  The roughly ground semiconductor substrate 28 is moved to the position of the vacuum chuck 38 of the second finish grinding stage 20 by rotating the index rotating table 34 90 degrees in the clockwise direction. Rotate and lower the diamond diamond grindstone 54 to cut and grind the back surface of the semiconductor substrate to a thickness of about 10 to 20 μm, and adjust the thickness of the semiconductor substrate to a desired thickness (for example, 80 to 220 μm, or 20 to 100 μm). ), The finish grinding cup wheel type diamond grindstone 54 is raised and moved away from the back surface of the semiconductor substrate.

  The semiconductor substrate 28 that has been subjected to finish grinding is moved to the chuck 40 position of the polishing stage 22 by rotating the index rotating table 34 90 degrees in the clockwise direction. By reciprocating in the direction, the ground surface of the ground substrate is polished to remove a 5 to 10 μm thickness with a grinding damage and finished to a mirror surface. Then, the polishing pad 56 is moved away from the back surface of the semiconductor substrate. It is done.

  The mirror-polished semiconductor substrate 28 is returned to the position of the first vacuum chuck 32 of the load / unload stage 17 by rotating the index rotating table 34 90 degrees clockwise. After being adsorbed by the suction pad of the robot 97, it is transported to the cleaning stage 24 where the ground / polished surface is cleaned and dried. Next, after being attracted again to the suction pad of the transport robot 97, it is transported to the unloading port 26 and stored in the cassette 26.

  After each index rotating table 34 is rotated 90 degrees in the clockwise direction, loading and unloading of the semiconductor substrate, rough grinding, finish grinding, and polishing are performed at each stage. . The polishing pad cleaning stage 23 cleans the polishing pad 56, and the polishing pad dressing stage 27 performs dressing of the cleaned polishing pad 56 and cleaning of the substrate chuck surface by the chuck cleaner 42. . In general, the allowance for the substrate layer to be flattened by polishing is 8 to 13 μm which is sufficient for the grinding streak to disappear.

  The cup wheel type diamond grindstone used for grinding differs depending on the machine manufacturer, but a rough wheel cup wheel type diamond grindstone 46 is a cup wheel type grindstone having a mesh number of 360 mesh, and a finish grinding cup wheel. The back surface of the substrate is ground flatly using a cup wheel type grindstone with a 1,500 mesh grindstone as the type diamond grindstone 54, or a cup wheel grindstone with a 325 mesh grindstone is used as the finish grinding grindstone The actual situation is that the back surface of the substrate is ground flat using a cup wheel type grindstone having a grinding number of 2,000 mesh.

In addition, surface inspection is performed to detect the presence or absence of cracks or scratches in the semiconductor substrate when the thinned semiconductor substrate is transported to the mounter by performing the grinding and polishing steps on the back of the semiconductor substrate on separate work tables. An inline-type substrate back surface flattening device including the device has also been proposed (see, for example, Patent Document 3).
JP 60-76959 A JP 2000-254857 A JP 2005-98773 A

  As the production of ultra-thin next-generation semiconductor substrates with a diameter of 12 inches (300 mm) and 16 inches (450 mm) and a thickness of 20 to 50 μm is desired, the back surface of a single semiconductor substrate is flattened faster. The advent of a flattening apparatus for grinding and polishing, which can be made high (high throughput) and has a small installation area (footprint) of the flattening apparatus for grinding and polishing, is desired by semiconductor device manufacturers.

  The built-in type flattening apparatus that performs the grinding / polishing process described in Patent Document 1 and Patent Document 2 on the same worktable is performed by performing the grinding / polishing process disclosed in Patent Document 3 on separate wafers. -It has the advantage of a smaller footprint than the in-line type flattening apparatus performed on the table, but the throughput is 12 to 13 sheets / hour with a 300 mm diameter substrate, and 15 to 16 of the in-line type flattening apparatus. Compared to sheets / hour. Further, since grinding and polishing are performed on the same work table, there are disadvantages that the work table and the processing tool are quickly soiled and the planarization accuracy is poor.

  In order to improve the disadvantage that the footprint of the in-line type flattening device described in Patent Document 3 is larger than that of the built-in type flattening device described in Patent Document 2, the present inventors have developed a built-in type flattening device. We focused on the fact that if we realize a throughput twice that of the above, the footprint will be about 75% of the footprint of two built-in type flattening devices.

  In order to realize this high throughput, the present inventors ground the back surface of a silicon substrate having a thickness of about 775 μm using three grinding heads, a rough grinding wheel head, a medium finish grinding wheel head, and a fine finish grinding wheel head. A large back allowance of about 745 μm is obtained to obtain a back-grinded substrate with excellent flatness, and then two of the highly flattened back-ground substrates are simultaneously subjected to a polishing step to polish the polish allowance to 2 to 5 μm. If possible, the increase in the footprint of the polishing stage can be suppressed, and the throughput of two built-in planarizers can be realized with one inline planarizer, and the footprint The present invention was conceived that it can be about 75% of that of two built-in type flattening apparatuses.

  An object of the present invention is to provide a planarization apparatus for a substrate that is capable of high throughput and suppresses an increase in footprint, and a method for planarizing the back surface of a semiconductor substrate using the apparatus.

According to a first aspect of the present invention, there is provided a planarization apparatus including a substrate storage stage outside a room, a grinding process stage, a polishing process stage, and a cleaning stage.
A substrate storage stage is provided on the left side outside the room from the front side to the back side of the flattening device,
In the room, in the front row of the room, the substrate edge holding type first transfer stage in the vicinity of the substrate storage stage, a pair of substrate temporary placement tables provided at the front and rear in the center, and one pad conditioner at the front right position A polishing stage capable of simultaneously polishing two substrates provided with a pair of substrate cleaning stages provided at the front and rear of the polishing stage;
In the center of the rear row of the room, four stages of substrate loading / unloading stage, rough grinding stage, intermediate finish grinding stage and precision grinding stage are placed in the clockwise direction. A grinding stage arranged concentrically on the index rotation table of the table, and
A substrate edge gripping type first conveying stage, which is an intermediate position between the grinding stage and the polishing stage, with respect to the substrate loading / unloading stage of the grinding stage; Provides a substrate edge gripping type second conveyance stage at a substantially point-symmetrical position,
The present invention provides a planarization apparatus for substrates.

  According to a second aspect of the present invention, there is provided the substrate flattening apparatus according to the first aspect, wherein the substrate loading / unloading stage, the rough grinding stage, the intermediate finish grinding stage, and the precision grinding stage are performed. These four stages are arranged concentrically on one index rotation table, and the vacuum chuck of the constituent members of the four stages of the grinding stage has a diameter substantially the same as the diameter of the substrate. -The upper surface of the porous ceramic disk-shaped mounting table and the upper surface of the non-breathable material mounting table are flush with the non-breathable material mounting table having an annular space at the top. The non-breathable material support base is rotatably supported on a spindle, and an annular space of the non-breathable material support base on the lower surface of the porous ceramic disk-shaped placement base is formed. Vacuum with vacuum means for depressurization The chuck is attached to the lower surface of the arm of the edge gripping transfer robot on the upper surface of the annular side wall portion of the non-breathable material support table in contact with the outer peripheral wall surface of the porous ceramic disk-shaped mounting table. The present invention provides a substrate flattening apparatus characterized by being a semiconductor substrate vacuum chuck having a structure in which an annular groove having a diameter and a depth into which a holding member for holding a substrate can enter is provided.

According to a third aspect of the present invention, there is provided a flattening method for a semiconductor substrate back surface, wherein the flattening of the back surface of the semiconductor substrate is performed after the next step using the flattening apparatus for a substrate according to the first aspect. Is to provide.
1) The substrate stored in the cassette of the substrate storage stage is grasped at the edge of the substrate by the substrate edge holding type first transfer stage transfer robot, and the substrate row provided on the index rotating table. Transfer onto the ding / unloading stage.
2) The substrate on the substrate loading / unloading stage is transferred to the rough grinding stage by rotating the index rotation table 90 degrees in the clockwise direction.
3) Roughly grind the back surface of the substrate using a diamond grindstone with a grinding number of 320 to 600 in a rough grinding stage. During this time, the step 1) is performed by the transfer robot of the substrate edge holding type first transfer stage, and a new substrate is transferred onto the substrate loading / unloading stage.
4) By rotating the index rotation table 90 degrees in the clockwise direction, the rough ground substrate is transferred to the intermediate finish grinding stage, and on the substrate loading / unloading stage. The substrate is transferred to the rough grinding stage.
5) Medium finish grinding is performed on the back surface of the substrate that has been coarsely ground using a diamond grinding wheel having a grinding number of 1,000 to 2,000 in a medium finish grinding stage. During this time, the back surface of the substrate is roughly ground using a diamond grinding wheel having a grinding number of 320 to 600 in the rough grinding stage, and a new substrate is loaded onto the substrate by the transport robot of the substrate edge holding type first transport stage. Is transferred onto the ding / unloading stage.
6) By rotating the index rotation table 90 degrees in the clockwise direction, the substrate that has been ground and ground is transferred to the precision grinding stage, and the substrate that has been ground is transferred to the finishing grinding stage. At the same time, the substrate on the substrate loading / unloading stage is transferred to the rough grinding stage.
7) The back surface of the substrate that has been subjected to intermediate finish grinding is precision ground using a diamond grinding wheel having a grinding number of 2,500 to 8,000 in a precision grinding stage. During this period, the back surface of the substrate that has been coarsely ground using a diamond wheel having a grinding number of 1,000 to 2,000 is ground in the intermediate finishing stage, and the back surface of the substrate is ground to 320 to 600 in the rough grinding stage. The new substrate is transferred onto the substrate loading / unloading stage by the substrate edge holding type first transfer stage transfer robot.
8) Rotate the index rotation table 90 degrees clockwise or 270 degrees counterclockwise to bring the precision ground substrate onto the substrate loading / unloading stage. The transferred and intermediate finish ground substrate is transferred to the precision grinding stage, and the coarsely ground substrate is transferred to the intermediate finish grinding stage. Next, the substrate that has been precisely ground on the substrate loading / unloading stage is transferred to a temporary placement table using the transfer robot of the first transfer stage of the substrate edge holding type. -Cleaning the unloading / unloading stage, and after cleaning, the substrate stored in the cassette of the substrate storage stage is moved to the edge of the substrate by the transfer robot of the substrate edge holding type first transfer stage. Grasp and transfer onto the substrate loading / unloading stage provided on the index rotation table.
9) Thereafter, the previous 7) step and 8) step are repeated. When there are two precision-ground substrates transferred to the temporary table, the substrate carrier on the polishing stage is used on the temporary table while the steps 7) and 8) are being performed. After transferring the pair of substrates to the upper part of the polishing surface plate of the polishing process stage, the pair of substrates is polished by the polishing process stage, and then the polished substrates are transferred to the substrate edge holding type second transfer stage. It is transferred to a cleaning stage using a transfer robot and cleaned there.

  By providing an index type grinding stage capable of substrate loading / unloading, rough grinding, intermediate finish grinding and precision grinding, and a polishing stage capable of polishing two substrates simultaneously. The rate of substrate grinding can be controlled, and the throughput of two built-in type flattening devices can be realized with one inline flattening device, and two footprints can be realized. It is possible to make it about 75% of that of a built-in type flattening device.

  By making the grinding process of the grinding stage into rough grinding, intermediate finish grinding and precision grinding, the amount of removal of the grinding damage layer of the substrate in the polishing stage can be set as small as 2 to 5 μm. . Further, by providing the intermediate finish grinding step, the substrate loss rate due to the substrate damage during precision grinding and the substrate transfer damage is reduced.

Hereinafter, the present invention will be described in more detail with reference to the drawings.
FIG. 1 is a plan view of an in-line type flattening device, FIG. 2 is a cross-sectional view of a vacuum chuck provided on an index rotating table, and FIG. 3 is a plan view of the vacuum chuck. FIG. 5 is a bottom view of the arm of the substrate edge holding type transfer robot as viewed from below, FIG. 5 is a front view of the arm of the substrate edge holding type transfer robot, and FIG. 6 is a view of the substrate placed on the vacuum chuck. FIG. 7 is a front view with a part cut away showing the relationship of the arms of the substrate edge holding type transfer robot, FIG. 7 is a front view of the polishing apparatus, and FIG. 8 is a sectional view of the polishing head also serving as a substrate carrier.

  In the flattening device 100 on the backside of the semiconductor substrate shown in FIG. 1, the flattening device 100 places the substrate storage stage 101 on the outside of the chamber partition wall 102 and the substrate edge gripping type first transport on the inside of the chamber partition wall 102. A stage 103, a grinding stage 104, a pair of temporary tables 105, a polishing stage 106, a substrate edge gripping type second transfer stage 108, and a cleaning stage 109 are provided. Reference numeral 110 denotes a base, and reference numerals 200a, 200b, and 200c denote substrate thickness measuring instruments.

  The substrate storage stage 101 is provided on the left side outside the room from the front side to the back side of the planarization apparatus. The substrate storage stage 101 includes a pair of substrate storage cassettes 101a and 101b stacked in two stages. Therefore, the substrate storage stage 101 can store 100 substrates in four storage cassettes.

  The substrate may be stored in the storage cassette as it is if the thickness of the back surface processed flat is 80 μm or more, but when the surface of the substrate is less than 80 μm flat processed For the purpose of preventing warpage and damage of the substrate, it is preferable to form a laminated body in which a semiconductor substrate w is laminated on a rigid support plate G made of a glass plate or a ceramic plate with an adhesive S interposed therebetween.

In the room, in the front row of the room, a substrate edge gripping type first transfer stage 103 in the vicinity of the substrate storage stage 101, a pair of substrate temporary placement tables 105a and 105b provided at the front and rear in the center, and a front right position A substrate cleaning stage 109 comprising a polishing stage 106 capable of simultaneously polishing two substrates provided with a pad conditioner 107, and a pair of spinners 109a and 109b provided at the front and rear of the polishing processing stage. The substrate loading / unloading stage s ₁ , rough grinding stage s ₂ , intermediate finish grinding stage s _3, and precision grinding stage are arranged in the center of the rear row in the room in the clockwise direction. - grinding stearate were concentrically arranged Bull 2 - - di indexed rotating Te - four stearyl di s ₄ di 104 provided, and the grinding stearyl - di 104 and the polishing pressure Stearyl - an intermediate position between the di-106, grinding stearyl - board di Russia - loading / unload - loading stearate - first conveying stearyl substrate edge gripping type relative to di s ₁ - a substantially point symmetrical with di 103 A substrate edge gripping type second conveyance stage 108 is provided at the position. The cleaning liquid ejected from the substrate cleaning stage 109 cleans the substrate carrier 106 a constituting the polishing stage 106.

The substrate edge holding type first transfer stage 103 is cleaned on the movement locus between the substrate storage stage 101 and the substrate loading / unloading stage s _{1 of the} holding arm of the articulated robot of the articulated robot 103. A cleaning device 103a for ejecting water is provided to clean the gripping arm. Further, a cleaning device 108a for spraying cleaning water onto the movement path between the polishing stage 106 and the cleaning stage 109 of the gripping arm of the articulated robot of the substrate edge holding type second transfer stage 108. Is provided for cleaning the gripping arm and cleaning the opposite surface of the polished substrate.

The grinding stage 104 includes a vacuum chuck 30, a rough grinding wheel head 104a, a medium finishing grinding wheel head 104b, and a precision grinding wheel head 104c. Above the substrate loading / unloading stage s _{1 of the} grinding stage 104, there are a cleaning brush 210 for cleaning the precision ground substrate surface and a ceramic cleaner 220 for cleaning the vacuum chuck 30. It is installed so that it can move back and forth and move up and down.

  As a cup wheel type diamond grindstone that is rotatably provided on the coarse grinding wheel head 104a, a resin wheel diamond grindstone having a grinding number (JIS general abrasive grain size) 320 to 600 is provided on the intermediate finishing grindstone head 104b. For example, a resin-bonded diamond wheel having a grinding number of 1,000 to 2,000 or a vitrified bond diamond wheel having a grinding number of 1,000 to 2,000 is used as a cup wheel-type grinding wheel provided in the precision grinding wheel head 104c. A metal bond diamond grindstone or vitrified bond diamond grindstone of 8,000 is preferable, and the dent of the substrate thickness in the vicinity of the notch provided on the substrate is prevented.

  FIG. 2 shows the vacuum chuck 30 of the grinding stage 104. Reference numeral 3 denotes a rotary shaft of the index rotary table, and 5 denotes a drive motor of the rotary shaft 3. Four of the vacuum chucks 30 are arranged on the index rotation table 2 at equal intervals on the same circumference, and one pair is shown in FIG.

  The vacuum chuck 30 is a support made of a non-breathable material having a porous ceramic disk-like mounting table 31 having a diameter substantially the same as the diameter of the work w, and having two large and small annular cavities 32b and 32c in the upper part. The upper surface 31a of the porous ceramic disk-shaped mounting table 31 and the upper surface 32a made of a non-breathable material are placed on the table 32 so that they are flush with each other. The vacuum spindle 33 is rotatably supported by the hollow spindle 33 through a vacuum 34, and the vacuum space 32b, 32c of the non-breathable material support base on the lower surface of the porous ceramic disk-shaped mounting base is decompressed. Means 40 are provided.

  On the upper surface 32a of the annular side wall portion of the support base 32 made of non-breathable material in contact with the outer peripheral wall surface of the porous ceramic disk-shaped mounting table 31, as shown in FIG. An annular groove 32d having a diameter and a depth into which the holding members 21, 21, 22 for holding the substrate attached to the lower surface of the system 10 can enter is provided. The inner diameter of the annular groove 32d is a diameter width that is slightly inside the outer peripheral edge of the rigid support plate. Depending on the handle 10a of the arm 10, a groove 32d 'having a depth into which the arm handle 10a can enter is provided if necessary (see FIG. 3).

  Returning to FIG. 2, the lower surface of the non-breathable material support base 32 is fixed to the upper concave support frame 34 with bolts 32 e and 32 e, and the lower portion of the upper concave support frame 34 is supported by the hollow spindle 33. Clutch mechanisms 50a and 50b are provided below the hollow spindle 33, and a drive motor 51 is provided on the lower clutch plate 50b. When the clutch plates 50a and 50b are connected, the hollow spindle 33 rotates by receiving the rotational force of the drive motor 51, and the concave support frame 34 supported by the spindle shaft by receiving the rotational drive force, and the port. The lath ceramic disk-shaped mounting table 31 also rotates.

  The vacuum means 40 includes a vacuum pump (not shown), a pipe 41 connected to the vacuum pump, a switching valve 42, a rotary joint 43, and a hollow spindle 33 connected to the rotary joint 43. The pipe 44 is arranged. A pipe 45 for supplying pure water is connected to the switching valve 42.

  In the hollow spindle 33, a pipe 46 communicating with the concave portion 34a of the upper concave support frame 34 is arranged, and a pump for supplying pure water for cooling via a rotary joint 47 and a pipe 48 connected thereto. Connected to P. The pure water supplied to the recess 34a of the concave support frame 34 cools the bottom of the non-breathable material support base 32.

  By operating the vacuum means 40, the rigid support plate G of the laminated body placed on the porous ceramic disk-shaped mounting table 31 is fixed to the porous ceramic disk-shaped mounting table 31 under reduced pressure. The After the vacuum of the vacuum means 40 is stopped, when the switching valve 42 is switched to the pure water supply side, the pressurized pure water cleans the porous ceramic disk-shaped mounting table 31.

  The edge gripping transfer robot 103 can be a known edge gripping transfer robot, but a pair of fixed gripping members provided on the lower surface of the arm 10 on the outer peripheral edge of the thin laminate shown in FIGS. The edge gripping type transfer robot 103 that is gripped by 21 and 21 and the movable gripping member 22 is more preferable.

  The edge gripping type transfer robot 103 is an articulated robot, and has a plate-like end effector arm 10 rotatably connected to the tip of the rotary shaft 61, and a lower surface of the tip of the end effector arm. A pair of fixed gripping members 21 and 21 fixedly provided, and a movable gripping member 22 fixed to a block 67 attached to the rear end lower surface of the end effector arm by a dual rod cylinder 62 so as to be able to advance and retreat. Prepare. The rod 63 of the dual rod cylinder advances by supplying compressed air from the air supply pipe 64 made of poly (tetrafluoroethylene) to the introduction pipe 65. Further, when the compressed air is exhausted from the exhaust pipe 66, it moves backward. In FIG. 4, the right introduction pipe 65 is connected to the air supply pipe 64, the center introduction pipe 65 is closed at the end, and is connected to the right introduction pipe 65 by a half union 68. The end effector arm 10 is made of ceramic, and the fixed gripping members 21 and 21 and the movable gripping member 22 are made of poly (ethyl ether ketone).

  As the object to be grasped, a laminated body in which the semiconductor substrate w is laminated on the disk-shaped rigid support plate G having a thickness of 0.5 to 1 mm using the adhesive S as described above is used. As the adhesive, an ultraviolet irradiation curable acrylic resin adhesive and a heat-foamable resin adhesive are used, and as the disc-shaped rigid support plate, a glass plate or a ceramic plate is used.

The laminated body in which the outer peripheral edge of the disc-shaped rigid support plate G is gripped by the arm 10 of the edge gripping type transfer robot 103 is mounted on the porous ceramic disc-shaped plate of the semiconductor substrate vacuum chuck 30 described above. The work of transporting to the mounting table 31 and mounting / fixing it on the porous ceramic disk-shaped mounting table is performed as follows.
1) The laminated body gripped by the edge gripping type transport robot 103 is transported above the porous ceramic disk-like mounting table 31 of the semiconductor substrate vacuum chuck.
2) The arm 10 of the edge gripping type transfer robot is moved down so as to bring the laminated disk-shaped rigid support plate G into contact with the porous ceramic disk-shaped mounting table 31 of the vacuum chuck 30. .
3) The vacuum pump of the vacuum chuck 30 is operated to depressurize the porous ceramic disk-shaped mounting table 31, and the laminated body is fixed to the porous ceramic disk-shaped mounting table.
4) The movable gripping member 22 provided on the lower surface of the arm of the edge gripping type transfer robot in the annular groove 32d of the vacuum chuck is moved backward by exhausting the compressed air of the dual rod cylinder 62 to move the movable gripping member 22. The arm 10 is moved forward by moving the joint of the edge gripping type transport robot away from the stacked body, and the fixed gripping members 21 and 21 are moved away from the stacked body (in FIG. 4, movement drawn by phantom lines). (From the position of the gripping member 22 and the fixed gripping members 21 and 21 drawn with solid lines to the position of the moving gripping member 22 drawn with solid lines and the position of the fixed gripping members 21 and 21 drawn with virtual lines).
5) The arm 10 of the edge gripping type transfer robot 103 is raised, and then the arm 10 is moved to the standby position by using the joint retreat, advance and rotation functions of the edge gripping type transfer robot 103.

Also, the operation of transporting the laminated body placed on the porous ceramic disk-like placement table 31 of the semiconductor substrate vacuum chuck 30 onto the temporary placement table 105 using the edge gripping transfer robot 103. Is performed as follows.
1) The arm 10 of the edge gripping type transfer robot is moved from the standby position to the upper side of the porous ceramic disk-like mounting table 31 of the semiconductor substrate vacuum chuck 30.
2) The arm of the edge gripping type transfer robot is lowered, and a pair of fixed gripping members 21 and 21 provided on the lower surface of the arm and the movable gripping member 22 are supported by a non-breathable material support base 32 of the vacuum chuck 30. In the annular groove 32d provided below the disk-shaped rigid support G of the laminated body.
3) The arm 10 is retracted by retreating the joint of the edge gripping type transfer robot (to the right) so that the pair of fixed gripping members 21 and 21 are in contact with the edges of the laminated disc-shaped rigid support plate G. (In FIG. 4, it moves from the position of the fixed gripping members 21 and 21 drawn by virtual lines to the position of the fixed gripping members 21 and 21 drawn by solid lines).
4) After the pair of fixed gripping members 21 and 21 come into contact with the edge of the laminated disk-shaped rigid support plate, the movable gripping member 22 is moved forward by causing the compressed air to be supplied 65 into the dual rod cylinder 62. Positioning is performed by bringing the gripping member 22 into contact with the disk-shaped rigid support plate G of the laminated body (in FIG. 4, moving from the position of the moving gripping member 22 drawn by the phantom line to the position of the moving gripping member 22 drawn by the solid line). I do.
5) The vacuum 40 of the vacuum chuck 30 is released, and the porous ceramic disk-shaped mounting table 31 of the laminated body is released.
6) The arm 10 of the edge gripping type transfer robot is raised, and then the arm is moved to transfer the laminate to the temporary table 105.

  Next, the polishing stage 106 will be described. As shown in FIGS. 1 and 7, the polishing stage 106 includes a substrate carrier (polishing head) 106a, a polishing surface plate (polishing pad) 106b having a polishing cloth affixed to the surface, a pad conditioner 107, and polishing. The agent slurry supply pipe 106c is a main component.

As shown in FIG. 7, the substrate carrier 106a can be reciprocated in the left-right direction along a guide rail 401 stretched horizontally on a frame 400 provided on the base 110. As shown in FIG. The screw coalesce 402 which supports the housing 407 of the substrate carrier 106a mode - is screwed to the ball screw 403 - ball which is rotated by a motor _{M 1.} The substrate carrier 106a mode - with being journaled for rotation on a spindle 405 which is rotated by the motor M _2, the air - which is movable up and down in the vertical direction by a cylinder 406. Further, the spindle 408 to journalled the polishing table 106b mode - rotated by the driving of the motor _{M 3.}

Substrate carrier 106a is motor - is moved to the temporary table 105b upward by screw screwed in ball screw 403 united 402 is moved to the left - ball which is rotated by a motor M _1. Further, by moving the ball screw in the reverse direction, the ball screw can be moved rightward from above the temporary table 105b to above the polishing surface plate 106b.

  The structure of the substrate carrier 106a is described in a number of patent publications. A polishing head which is the substrate carrier 106a shown in FIG. 8 is disclosed in Japanese Patent Laid-Open No. 2005-7521. In the head structure of the substrate carrier shown in FIG. 8, 505 is a hollow spindle shaft, 504 is a bowl-shaped housing part, 505a is a coupler, and the bowl-shaped housing part is supported on the lower part of the spindle 405. Reference numeral 506 denotes a diaphragm made of a flexible material. The diaphragm 506 is clamped horizontally by an annular flange 507 at the lower end of the annular side wall 503a of the bowl-shaped housing portion and tightened with a bolt 509. Reference numeral 508 denotes a rigid support plate, which has a gas passage 508a in the vertical direction in the center, and has a recess (second pressurizing chamber) 508b formed through the gas passage on the lower surface. Reference numeral 510 denotes a flange ring having an outward flange portion 510a, which is fixed to the center upper surface portion of the diaphragm with bolts 511. The rigid support plate 508 is also fixed to the lower surface of the diaphragm 506 by the bolt 511.

  Reference numeral 512 denotes a height position adjusting mechanism capable of moving the fixing disk 512a up and down in the vertical direction. A fixing disk 512a is provided at the lower end of a rod-shaped member 512b whose upper part is threaded. An insert 513 is provided above the bowl-shaped housing portion, and a rod-shaped member 512b is screwed therein. By raising the rod-shaped member 512b, the fixing disk 512a is engaged with the flange portion 510a. Reference numeral 516 denotes a gas supply / exhaust tube provided in the hollow spindle 205, one end of which is connected to a tube having a vacuum / pressure gas switching valve (not shown), and the other end is a rigid support plate. The central gas passage 508a communicates with the central gas passage 508a through a joint.

  Reference numeral 517 denotes a first pressurizing chamber formed by the inner side of the bowl-shaped housing portion 504 and the upper surface side of the diaphragm 506. Reference numeral 518 denotes a gas passage for supplying gas to the first pressurizing chamber 517. A pressurized gas is supplied via the inside of the shaft 505. The supplied pressurized gas pressurizes the upper surface of the diaphragm 506.

  Reference numeral 519 denotes a backing material having a thickness of 2.5 to 5.0 mm. As described above, the backing material 519 has, for example, a five-layer structure of flexible rubber film / pressure-sensitive adhesive / thermoplastic resin film / urethane foam resin layer / adhesive resin layer. The flexible rubber film 519 constituting the backing material is spread on the lower surface of a rigid annular ring 530 fixed by a plurality of bolts 523 to the step 508c at the outer peripheral edge of the lower end surface of the rigid support plate 508. Highly confidential second pressurizing chambers 508b and 521 having a gap h of 0.1 to 5 mm are formed by the circular flexible rubber film 519 and the lower surface concave portion of the rigid support plate 508. Stainless steel, aluminum, etc. are used for the rigid annular ring 530 material.

  The rigid annular ring 530 and the flexible rubber film 519 are bonded by inserting the rigid annular ring 530 into the cavity of the molding die, and then filling the flexible rubber mass into the cavity to soften the rubber. The mold is heated to a temperature equal to or higher than, for example, 150 to 185 ° C., and compression-molded with a clamping pressure of 1 to 200 tons to heat the flexible rubber film to the side wall surface and lower circumferential surface of the rigid annular ring. It is preferable to carry out pressure forming and bonding, and cooling this for 5 to 25 minutes.

  The annular holding ring 522 is formed with the same width and the same diameter as the ring width L of the rigid annular ring 530. The material is made of glass fiber reinforced epoxy resin or ceramic, and the annular holding ring 522a having a thickness of 0.05 to 2 mm is pressure-sensitive bonded on the adhesive resin layer of the backing material 519 stretched on the lower surface of the rigid annular ring 530. It is pasted with an agent. A substrate storage pocket portion 525 is formed by the inner side wall of the annular holding ring 522 and the lower surface of the circular adhesive resin layer of the backing material. Pressurized air is supplied from a tube 516 to the second pressurizing chambers 508b and 521 from the upper surface side of the circular flexible membrane, and the second pressurizing chamber is pressurized or the tube 516 is evacuated to the second pressurizing chamber. Is structured to be depressurized.

  The annular retaining ring 522 may have a double structure in which an inner annular retaining ring 522b made of resin is provided inside the ceramic outer annular retaining ring 522a with a gap width d of about 0.5 to 1.5 mm. . The resin inner annular holding ring 522b preferably has a Rockwell hardness (ASTM D785) of 110 to 150 in R scale. As the material, poly (tetrafluoroethylene), poly (difluorodichloroethylene), polyacetal, glass fiber reinforced epoxy resin, nylon 6,10, nylon 6,12, polyimide, and other resins with good sliding properties are used. The The coefficient of dynamic friction between the polishing cloth of the polishing surface plate and the annular holding ring is preferably 0.30 or more.

The ceramic outer annular retaining ring 522a preferably has a Vickers hardness of 300 to 2,000 kg / mm ² or a Knoop hardness of 200 to 2,800 kg / mm ² . Alumina, silicon carbide, silicon nitride, zirconium oxide, silicon oxide, etc. are used as ceramic grains, and methyl methacrylate / butyl methacrylate copolymer, methyl methacrylate / n-propyl methacrylate copolymer, methyl methacrylate are used as binders. A green sheet produced using an aqueous emulsion such as a butyl methacrylate / ethyl acrylate copolymer is punched into an annular shape and fired at 1,100-1600 ° C. to form a mold.

  The ratio (L / l) of the ring width (L) of the outer annular holding ring 522a to the ring width (l) of the inner annular holding ring 522b is 1 to 3, and the sum of the ring widths (L + 1) of both is 18 ~ 30 mm is preferred. The ring thickness of the inner annular holding ring 522b and the ring thickness of the outer annular holding ring 522a are the same, the same as the value obtained by adding the polishing allowance to the thickness of the substrate to be polished, or further adding 1 to 10 μm to this value. Value. The thickness of these annular holding rings 522a and 522b is, for example, 0.3 to 2 mm. The surfaces of the inner annular retaining ring 522b and the outer annular retaining ring 522a that are in contact with the polishing pad are flush with each other.

  Reference numeral 524 denotes a rubber seal ring. Reference numeral 525 denotes a substrate storage pocket portion, which is formed by the side wall of the resin inner annular holding ring 522b and the surface of the adhesive resin layer 519e of the backing material. As described above, it is more preferable that the flexible rubber film 519 is attached (heat-press molding and simultaneous adhesion) so as to cover the outer peripheral wall and the upper surface of the rigid annular ring 530. The depth value of the substrate storage pocket portion 525 is smaller than the thickness of the laminated body to be polished.

  Aluminum and stainless steel can be used as the material for the rigid support plate 508 and the material for the rigid annular ring 530.

The step of polishing the substrate using the carrier head 106a shown in FIGS. 7 and 8 is performed as follows.
(1) The substrate carrier head 106a is moved onto the laminate that has been transported to the temporary table 105 in advance, and the substrate carrier head 106a is lowered to contact the rigid support support G surface of the laminate, and then added. A pressurized gas is supplied to the pressure chamber 518 to press the substrate carrier head 106a, the tube 516 is decompressed to decompress the second pressure chambers 508b and 521, and the flexible film 519 of the substrate carrier head 106a is sucked. Thus, the substrate is sucked up by the adhesive resin layer of the backing material and fixed to the pocket portion 525 of the carrier head 106a.

(2) Next, the carrier head 106a holding the laminate is moved above the polishing platen 106b of the polishing apparatus, and then the carrier head is lowered to polish the polishing platen 106b supported by the spindle 408. Abut against cloth.
(3) Stop decompression of the tube 516 of the substrate carrier head 106a, switch to pressurized gas, supply pressurized air to the second pressurizing chambers 508b and 521, and supply pressurized gas to the hollow spindle 505 as well. The substrate carrier head presses the laminated body onto the polishing cloth of the polishing surface plate 106b by expanding the flexible film of the backing material with the pressurized gas supplied to the one pressurizing chamber 518. At this time, the pressure in the first pressurizing chamber 518 is higher than the pressure in the second pressurizing chambers 508b and 521.

  (4) While supplying pressurized gas to the first pressurizing chamber 518 and the second pressurizing chambers 508b and 521, the hollow spindle 505 of the carrier head holding the laminated body and the spindle 408 of the polishing surface plate 106b are rotated. By doing so, the substrate on the lower surface of the laminate and the polishing cloth are slid to polish the surface of the substrate. At this time, polishing is performed while the abrasive slurry is supplied from the supply nozzle 106c to the surface of the polishing pad.

The rotation speed of the polishing surface plate 106b is 10 to 150 rpm, the rotation speed of the substrate carrier head 106a is 10 to 150 rpm, and the pressure applied to the polishing cloth by the substrate held on the adhesive resin layer of the backing material 519 of the carrier is 0. 05 to 0.3 kg / cm ² , preferably the gas pressure supplied to the first pressurizing chamber 18 is 100 to 300 g / cm ² , and the gas pressure supplied from the pipe 516 to the second pressurizing chamber 521 is 100 to 200 g. / Cm ² .

  As the abrasive slurry, a slurry in which abrasive grains such as colloidal silica, cerium oxide, alumina, boehmite and manganese dioxide are dispersed in pure water is used. If necessary, the slurry is mixed with a surfactant, a chelating agent, a pH adjuster, an oxidizing agent and a preservative. The abrasive slurry is supplied to the polishing cloth surface at a rate of 50 to 1,500 cc / min.

  When polishing the substrate, the substrate receives a pressure change due to irregular undulations on the surface of the polishing cloth, but the pressure applied to the flexible film of the backing material 519 supporting the back surface of the substrate from the second pressurizing chambers 508b and 521 is Pascal. Based on this principle, the same pressure is applied to any part, so that the substrate can easily follow the undulation of the surface shape of the polishing pad.

  After the polishing, the supply of pressurized gas to the first pressurizing chamber 518 is stopped, and the spindle 505 of the carrier head 106a is slightly raised from the polishing cloth of the polishing surface plate, whereby the pressure supplied into the pipe 516 is increased. Since the flexible film is expanded by compressed air, the polished laminate can be easily peeled off from the adhesive resin layer of the backing material 519 of the carrier.

  The operation of planarizing the back surface of the semiconductor substrate using the substrate planarization apparatus 100 shown in FIG. 1 is performed through the following steps.

1) A multi-joint type transfer of a substrate edge holding type first transfer stage 103 for a substrate laminate stored in the cassette 101a of the substrate storage stage 101 (the rigid support plate surface is the upper surface and the substrate surface is the lower surface). The robot grasps the outer peripheral edge of the rigid support plate G of the laminated body and transfers it to the substrate loading / unloading stage s ₁ provided on the index rotating table 2 so that the substrate surface is raised. in the direction stearate - it is placed on the di s _1.

By rotating 90 degrees Bull 2 clockwise, the substrate B - - 2) indexed rotating Te loading / unload - loading stearate - transferring to di s ₂ - a substrate on the di rough grinding stearate.

3) Roughly grind the back surface of the substrate with a coarse grinding stage s ₂ using a resin bond diamond grindstone with a grinding number of 320 to 600. During this time, the first transport stearyl substrate edge retentive - performed step of the 1) in articulated transfer robot di 103, new laminate substrate board Russia - loading / unload - loading stearyl - di s ₁ above It is transferred to.

4) By rotating the index rotating table 2 90 degrees in the clockwise direction, the coarsely ground laminated substrate is transferred to the intermediate finish grinding stage, and the substrate loading / unloading stage is performed. The substrate on the s ₁ is transferred to the rough grinding stage s ₃ .

5) finish grinding stearyl - Middle-finish grinding the rough grinded back surface of the substrate using a diamond grindstone of abrasive numbered 1,000-2,000 di s _3. During this time, the rough grinding stearate - with back surface of the substrate is rough grinding using a resin-bonded diamond grinding wheel abrasive numbered 320-600 in di s _2, the first transport stearyl substrate edge retentive - articulated transfer robot di 103 new laminate substrate board b by - is transferred onto the di s ₁ - loading / unload - loading stearate.

6) By rotating the index rotation table 90 degrees in the clockwise direction, the intermediate finish ground substrate is transferred to the precision grinding stage s ₄ , and the roughly ground substrate is transferred to the intermediate finish grinding stage s. ₃ and the substrate on the substrate loading / unloading stage s ₁ is transferred to the rough grinding stage s ₂ .

7) Precision Grinding stearyl - precisely ground in fine grinding has been back surface of the substrate using a diamond grindstone of abrasive numbers 2,500～8,000 di s _4. During this time, in the intermediate finish grinding stage s ₃ , the back surface of the substrate that has been coarsely ground using a diamond wheel having a grinding number of 1,000 to 2,000 is subjected to intermediate finish grinding, and in the rough grinding stage s ₂ , the back surface of the substrate is ground. while rough grinding using a resin-bonded diamond wheel turn 320-600, the substrate edge retentive first conveying stearyl - board a new laminate substrate by di transfer robot Russia - loading / unload - loading stearyl - di s ₁ Transported up.

8) Substrate loading / unloading stage s _{1 by} rotating index rotating table 2 by 90 degrees clockwise or by rotating 270 degrees counterclockwise. The substrate that has been transported upward and subjected to the intermediate finish grinding is transported to the precision grinding stage s ₄ , and the substrate that has been coarsely ground is transported to the intermediate finishing grinding stage s ₃ . Next, the precision-ground substrate on the substrate loading / unloading stage s ₁ is reversed and transferred to the temporary table 105 using the multi-joint type transfer robot 103 of the substrate transfer holding type first transfer stage. (temporary rigid support plate surface is the upper surface table on the) and, thereafter, the substrate b - loading / unload - loading stearate - Vacu located di s ₁ - Muchakku 30 were washed, after completion of the washing, the substrate housing The stacked substrate stored in the cassette of the stage 101 is held on the index rotating table 2 by grasping the edge of the rigid support plate G of the stacked body by the transfer robot of the substrate edge holding type first transfer stage 103. substrate provided Russia - loading / unload - loading stearate - transferring onto di s _1.

  9) Thereafter, the previous 7) step and 8) step are repeated. When the number of precision-ground laminate substrates transferred to the temporary tables 105a and 105b becomes two, the substrate carrier 106a of the polishing stage 106 is removed during the steps 7) and 8). The pair of stacked substrates on the temporary table are transferred to the upper part of the polishing table 106b of the polishing stage, and then the pair of substrates are simultaneously polished on the polishing stage, and then held on the substrate carrier 106a. The polished substrate that has been polished is held at the edge of the rigid support plate G by the multi-joint type transfer robot of the substrate edge holding type second transfer stage 108, and then transferred to the upper part of the substrate cleaning stage 109. The surface of the rigid support plate G is made the lower surface by reversing the arm, the surface of the rigid support plate G is cleaned by the cleaning brush 108a, and after being inverted, it is transferred onto the spinner 109a of the cleaning stage. Been the substrate surface is cleaned.

  When the cleaning is completed, the laminated body is transferred to the outdoor storage cassette by the multi-joint transfer robot of the substrate edge holding type second transfer stage 108 or transferred to the mounter device of the next process stage. After the transfer, the arm of the substrate edge holding type second transfer stage 108 is cleaned by a spinner 109a.

Example 1
Using the substrate flattening apparatus 100 shown in FIG. 1, 740 μm is removed from the back surface (silicon substrate surface) of a semiconductor substrate (thickness: 775 μm) printed on a 300 mm diameter silicon substrate, and grinding is performed to a thickness of 30 μm. Polishing processing was performed. Coarse grinding is performed using a resin bond diamond grinding wheel (cup wheel type) with grinding number 325, and a machining allowance of 550 μm is used for intermediate finish grinding. The removal allowance of 160 μm was used, and the precision grinding was performed using a metal bond diamond grindstone (cup wheel type) with an abrasive number of 8,000 to obtain an allowance of 30 μm.

  A semiconductor substrate having a thickness of 775 μm was used by laminating a silicon foam of a substrate on a disc-shaped glass plate having a diameter of 310 mm and a thickness of 1 mm using a heating foam adhesive from Sekisui Chemical Co., Ltd. as a laminate.

The rotational speed of each grinding wheel in the grinding stage 104 was 3,000 rpm, and the rotational speed of the vacuum chuck 30 was 200 rpm during rough grinding, 120 rpm during intermediate finish grinding, and 120 rpm during precision grinding. The following table shows the grinding conditions and grinding time for each grinding stage.
Table 1

The polishing conditions were such that the number of rotations of both the polishing head spindle 405 and the polishing platen spindle 408 was 100 rpm, and the pressure on the polishing cloth surface of the substrate was 150 g / cm ² .

  Incidentally, (a) the substrate scan time at the load port is 20 seconds, (b) the substrate transport stage transport time (start, substrate grip / temporary table, placement) is 23 seconds, (c) the index. The rotation time of the rotary table 2 is 3 seconds, the rate limiting time of the grinding process (rough grinding) is 150 seconds, (d) the substrate cleaning is 10 seconds, and (e) the carrier standby position is moved upward from the temporary table. The moving time is 30 seconds, (f) the transfer time of the carrier from the substrate chuck to the polishing platen is 20 seconds, (g) the polishing time is 90 seconds, and (h) the substrate polished from the polishing stage is unloaded. -The time for loading and storing in the storage cassette or transporting to the next mounter process was 20 seconds.

  Since the rotation time of the index rotation table 2 is 3 seconds, the throughput time in the grinding stage is 153 seconds. The rate limiting of the polishing stage is 130 seconds, which is the sum of (f) + (g) + (h). Therefore, the throughput of the flattening apparatus is 23.5 sheets / hour, which is a value obtained by dividing 3,600 seconds by 153 seconds.

  In addition, no warpage was observed in the obtained ground and polished semiconductor substrate having a thickness of 25 μm. Moreover, the loss rate when it is made into a semiconductor chip is about 12%, which is compared with the existing built-in type 300 mm diameter substrate flattening device 80 μm product loss rate 28-30% reported in the industry. The present in-line flattening apparatus of the invention is excellent in each stage and the product loss rate is low.

  The semiconductor substrate back surface grinding / polishing method of the present invention is excellent in throughput, has a low product loss rate, and is highly productive.

It is a top view of the planarization apparatus of an in-line system. It is sectional drawing which notched a part of vacuum chuck provided in the index rotation table. It is a top view of a vacuum chuck. It is the bottom view which looked at the arm of the substrate edge maintenance type conveyance robot from the lower direction. It is a front view of the arm of a substrate edge holding type transfer robot. It is the front view which notched the part which shows the relationship between the board | substrate mounted in the vacuum chuck | zipper, and the arm of a board | substrate edge holding | maintenance type transfer robot. It is a front view of a polisher. It is sectional drawing of the polishing head which served as the substrate carrier. It is a perspective view of a planarization apparatus. (Known) It is a top view of a planarization apparatus. (Known)

Explanation of symbols

2 Index rotation table 30 Vacuum chuck 100 Substrate flattening device 101 Substrate storage stage 103 Substrate edge gripping type first transfer stage 104 Grinding stage s ₁ Substrate loading / unloading stage S ₂ Coarse grinding stage s ₃ Finish grinding stage s ₄ Precision grinding stage 105 Temporary table 106 Polishing stage 107 Pad conditioner 108 Substrate edge gripping type second conveyance stage 109 Cleaning stage -G 110 base 200 substrate thickness measuring instrument

Claims (3)

In a flattening apparatus including a substrate storage stage outdoors, a grinding process stage, a polishing process stage, and a cleaning stage,
A substrate storage stage is provided on the left side outside the room from the front side to the back side of the flattening device,
In the room, in the front row of the room, the substrate edge holding type first transfer stage in the vicinity of the substrate storage stage, a pair of substrate temporary placement tables provided at the front and rear in the center, and one pad conditioner at the front right position A polishing stage capable of simultaneously polishing two substrates provided with a pair of substrate cleaning stages provided at the front and rear of the polishing stage;
In the center of the rear row of the room, four stages of substrate loading / unloading stage, rough grinding stage, intermediate finish grinding stage and precision grinding stage are placed in the clockwise direction. A grinding stage arranged concentrically on the index rotation table of the table, and
A substrate edge gripping type first conveying stage, which is an intermediate position between the grinding stage and the polishing stage, with respect to the substrate loading / unloading stage of the grinding stage; Provides a substrate edge gripping type second conveyance stage at a substantially point-symmetrical position,
A planarization apparatus for a substrate characterized by the above.   4. The substrate flattening apparatus according to claim 1, wherein four stages of a substrate loading / unloading stage, a rough grinding stage, an intermediate finish grinding stage, and a precision grinding stage are performed. The vacuum chuck of the constituent members of the four stages of the grinding stage arranged concentrically on one index rotating table is a porous ceramic disc having the same diameter as the substrate. The mounting table is placed on a non-breathable material support base having an annular space at the top so that the upper surface of the porous ceramic disk-shaped mounting table is flush with the top surface of the non-breathable material support base. A vacuum means for rotatably supporting a support base made of air permeable material on a spindle and for decompressing an annular space of the support base made of non-breathable material on the lower surface of the porous ceramic disk-like mounting table. A vacuum chuck provided, A grip for holding a substrate attached to the lower surface of the arm of the edge gripping type transfer robot on the upper surface of the annular side wall portion of the non-breathable material support table in contact with the outer peripheral wall surface of the porous ceramic disk-shaped mounting table. A flattening apparatus for a substrate, which is a vacuum chuck for a semiconductor substrate having a structure in which an annular groove having a diameter and a depth into which a member can enter is provided. A method for planarizing a back surface of a semiconductor substrate, wherein the planarizing device for a substrate according to claim 1 is used to planarize the back surface of the semiconductor substrate through the following steps.
1) The substrate stored in the cassette of the substrate storage stage is grasped at the edge of the substrate by the substrate edge holding type first transfer stage transfer robot, and the substrate row provided on the index rotating table. Transfer onto the ding / unloading stage.
2) The substrate on the substrate loading / unloading stage is transferred to the rough grinding stage by rotating the index rotation table 90 degrees in the clockwise direction.
3) Roughly grind the back surface of the substrate with a rough grinding stage using a diamond grindstone with a grinding number of 320 to 600. During this time, the step 1) is performed by the transfer robot of the substrate edge holding type first transfer stage, and a new substrate is transferred onto the substrate loading / unloading stage.
4) By rotating the index rotation table 90 degrees in the clockwise direction, the rough ground substrate is transferred to the intermediate finish grinding stage, and on the substrate loading / unloading stage. The substrate is transferred to the rough grinding stage.
5) Medium finish grinding is performed on the back surface of the substrate that has been coarsely ground using a diamond grinding wheel having a grinding number of 1,000 to 2,000 in a medium finish grinding stage. During this time, the back surface of the substrate is roughly ground using a diamond grinding wheel having a grinding number of 320 to 600 in the rough grinding stage, and a new substrate is loaded onto the substrate by the transport robot of the substrate edge holding type first transport stage. Is transferred onto the ding / unloading stage.
6) By rotating the index rotation table 90 degrees in the clockwise direction, the substrate that has been ground and finished is transferred to the precision grinding stage, and the substrate that has been ground is transferred to the finishing grinding stage. At the same time, the substrate on the substrate loading / unloading stage is transferred to the rough grinding stage.
7) The back surface of the substrate that has been subjected to intermediate finish grinding is precision ground using a diamond grinding wheel having a grinding number of 2,500 to 8,000 in a precision grinding stage. During this time, in the intermediate finish grinding stage, the back surface of the substrate that has been coarsely ground using a diamond wheel having a grinding number of 1,000 to 2,000 is subjected to intermediate finish grinding. The new substrate is transferred onto the substrate loading / unloading stage by the substrate edge holding type first transfer stage transfer robot.
8) By rotating the index rotation table 90 degrees clockwise or 270 degrees counterclockwise, the precision ground substrate is placed on the substrate loading / unloading stage. The transferred and intermediate finish ground substrate is transferred to the precision grinding stage, and the coarsely ground substrate is transferred to the intermediate finish grinding stage. Next, the substrate that has been precisely ground on the substrate loading / unloading stage is transferred to a temporary placement table using the transfer robot of the first transfer stage of the substrate edge holding type. -Cleaning the unloading / unloading stage, and after cleaning, the substrate stored in the cassette of the substrate storage stage is moved to the edge of the substrate by the transfer robot of the substrate edge holding type first transfer stage. The substrate is picked up and transferred onto a substrate loading / unloading stage provided on the index rotating table.
9) Thereafter, the previous 7) step and 8) step are repeated. When there are two precision-ground substrates transferred to the temporary table, the substrate carrier on the polishing stage is used on the temporary table while the steps 7) and 8) are being performed. After transferring the pair of substrates to the upper part of the polishing surface plate of the polishing process stage, the pair of substrates is polished by the polishing process stage, and then the polished substrates are transferred to the substrate edge holding type second transfer stage. It is transferred to a cleaning stage using a transfer robot and cleaned there.

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