JP5674148B2 - Glass substrate polishing method and polishing apparatus - Google Patents

Description

  The present invention relates to a glass substrate polishing method and polishing apparatus.

  Glass substrates for FPD (Flat Panel Display) such as liquid crystal displays are cut and folded into glass plates of a predetermined rectangular size in the cutting process using a glass ribbon formed by a glass ribbon forming device such as a float kiln. Then, by chamfering the end face in a chamfering process, the glass substrate is manufactured to a predetermined outer dimension. And this glass substrate is transferred to the polishing step through the cleaning step and the inspection step arranged after the chamfering step, and is required for the FPD glass substrate by polishing and removing fine irregularities and waviness on the surface. It is manufactured in a thin plate shape that satisfies the flatness.

  In the polishing step, the non-polished surface of the glass substrate is adsorbed and fixed to a table, the table is transferred to a polishing unit, and a polishing liquid (slurry) is supplied to the polished surface of the glass substrate while polishing the glass substrate with a polishing tool. To polish.

  At the time of this polishing, the polishing liquid enters the edge of the non-polished surface of the glass substrate from the edge of the glass substrate, and cerium oxide, which is a component of the polishing liquid, and the glass component scraped off by the polishing are not on the glass substrate. There is a problem that the edge is contaminated by adhering to the edge of the polishing surface.

  In order to prevent this problem, in the wafer polishing method of Patent Document 1, a protective film made of a protective material made of synthetic resin is formed on the non-polished surface of the wafer. The edge of the non-polished surface of the wafer is protected from the polishing liquid by fixing the non-polished surface of the wafer to the polishing jig via this protective film.

  Further, in the wafer polishing method disclosed in Patent Document 2, a buffer material such as polyhydric alcohol is interposed between the non-polished surface of the wafer and the wafer mounting plate to thereby remove the non-polished surface of the wafer. The edge is protected from the polishing liquid.

JP-A-62-51226 JP-A-6-61203

  By the way, a glass substrate polishing apparatus called a continuous polishing apparatus polishes a polishing surface of a glass substrate while conveying a table for adsorbing and fixing the non-polishing surface of the glass substrate by a predetermined loop. In other words, a glass substrate suction fixing portion, a polishing portion, a glass substrate removal portion, and a table cleaning portion are sequentially provided in the transport path of the table constituting the loop. The non-polished surface of the glass substrate before polishing is fixed by suction to a table positioned at the suction fixing unit, and thereafter, the glass substrate is conveyed to the polishing unit by the table and polished. And the glass substrate after grinding | polishing is conveyed by the said table outside by a table, and is removed from a table here. The table from which the glass substrate has been removed is cleaned while passing through the cleaning section, and is prepared as a suction table for the next glass substrate.

  Here, the polishing method disclosed in Patent Document 1 is a method in which a protective film is formed in advance on a non-polished surface of a wafer and then polished. Further, the polishing method disclosed in Patent Document 2 is to provide a protective film between a non-polished surface of a wafer and a wafer mounting plate.

  However, the size of the glass substrate is mainly the one whose vertical and horizontal dimensions exceed 1000 mm, and it is difficult to form the protective film in advance on such a large glass substrate due to difficulty in handling. In addition, since a separate facility for forming the protective film is required, there is a problem that it is difficult to employ the polishing method of Patent Document 1 as the glass substrate polishing method.

  On the other hand, adopting the polishing method of Patent Document 2 in which a protective film is provided between a non-polished surface of a wafer and a wafer mounting plate in a glass substrate polishing apparatus that directly adsorbs the glass substrate by a table is a polishing process. It was impossible because the glass substrate sometimes became unstable.

  The table of the glass substrate polishing apparatus has a suction surface made of a self-adsorbing sheet material. When the surface of the sheet material is dried, the self-adsorption property of the sheet material becomes weak, and the glass substrate may break during polishing of the glass substrate. Therefore, in order to prevent drying of the non-polished surface of the glass substrate that is adsorbed and fixed to the sheet material, or to increase the self-adsorption property of the sheet material, the glass substrate is used as the sheet material via a drying prevention liquid. It is necessary to fix by adsorption. Also in this case, it was necessary to supply the anti-drying solution well between the glass substrate and the sheet material.

  The present invention has been made in view of such circumstances, can prevent contamination of the edge of the non-polished surface of the glass substrate by the polishing liquid, and favorably adsorb and fix the non-polished surface of the glass substrate to the table. An object of the present invention is to provide a polishing method and a polishing apparatus for a glass substrate.

In order to achieve the above object, the glass substrate polishing method of the present invention is a region in which the entire non-polished surface of the glass substrate of the table is attracted and fixed toward the table that adsorbs and fixes the non-polished surface of the glass substrate. Next, spray the anti-drying solution from the first nozzle, and then apply the buffer solution from the second nozzle to the area where the edge of the non-polished surface of the glass substrate of the table is adsorbed and fixed to the table. A liquid spraying step for spraying , wherein the application amount of the buffer solution per unit area of the table is set to be larger than the application amount of the drying preventing liquid per unit area of the table ; The entire non-polished surface of the glass substrate is adsorbed and fixed to the table via the anti-drying liquid, and the edge of the non-polished surface of the glass substrate is adsorbed and fixed to the table via the buffer solution. A glass substrate fixing step that, non-abrasive surface to the table is and a polishing step of polishing the polished surface of the glass substrate attracted fixed, the polished surface by the polishing tool while supplying a polishing liquid.

In order to achieve the above object, the glass substrate polishing apparatus of the present invention adsorbs and fixes the non-abrasive surface of the glass substrate to the table and the entire area of the non-abrasive surface of the glass substrate of the table toward the table. A first nozzle that sprays an anti-drying liquid on an area to be fixed, and a second nozzle that sprays a buffer liquid on an area where the edge of the non-polished surface of the glass substrate of the table is adsorbed and fixed to the table. The amount of the buffer solution applied per unit area of the table is set to be larger than the amount of the anti-drying solution applied per unit area of the table. The liquid spray part and the entire area of the non-polished surface of the glass substrate are adsorbed and fixed to the table via the anti-drying liquid, and the edge of the non-polished surface of the glass substrate is intercalated via the buffer solution. The A glass substrate fixing portion that is adsorbed and fixed to a glass, and a polishing portion that polishes the polishing surface with a polishing tool while supplying a polishing liquid to the polishing surface of the glass substrate whose non-polishing surface is adsorbed and fixed to the table. ing.

  According to the present invention, first, the anti-drying liquid is sprayed from the first nozzle toward the table, and the anti-drying liquid is applied to the region where the entire area of the non-polished surface of the glass substrate is adsorbed and fixed. The buffer solution is sprayed from the second nozzle toward the table, and the buffer solution is applied to the region where the edge of the non-polished surface of the glass substrate is adsorbed and fixed to the table.

  Next, the entire non-polished surface of the glass substrate is adsorbed and fixed to the table via the anti-drying liquid by the glass substrate fixing portion, and the edge of the non-polished surface of the glass substrate is fixed via the buffer solution. Adhere to the table.

  Next, the polishing surface is polished by a polishing tool while supplying a polishing liquid to the polishing surface of the glass substrate in the polishing unit. During this polishing, the edge of the non-polished surface of the glass substrate is protected by the buffer solution, so that the edge is not contaminated by the polishing liquid.

  As described above, the present invention sprays the drying preventing liquid and the buffer solution from the liquid spraying part toward the table, so that the contamination of the edge of the non-polished surface of the glass substrate by the polishing liquid can be prevented, and the glass substrate It is possible to satisfactorily adsorb and fix the non-polished surface to the table.

  According to the glass substrate polishing method of the present invention, in the liquid spraying step, the drying prevention is performed from the first nozzle while relatively moving at least one of the table and the first and second nozzles. While spraying a liquid, it is preferable to spray the buffer solution from the second nozzle.

  According to the glass substrate polishing apparatus of the present invention, the liquid spraying unit is configured to prevent the drying from the first nozzle while relatively moving at least one of the table and the first and second nozzles. While spraying a liquid, it is preferable to spray the buffer solution from the second nozzle.

  When moving the table, first, an empty table is transported to the liquid spraying section along the table transport path. Then, while transporting the table along the table transport path, the drying prevention liquid is sprayed from the first nozzle toward the table, the drying prevention liquid is applied to the table, and the second nozzle is applied to the table. Spray the buffer solution and apply the buffer solution to the table.

  Further, when the first and second nozzles are moved, the first and second nozzles are moved with respect to the upper surface of the fixed table to spray the drying preventing liquid and the buffer solution on the table. However, when polishing the glass substrate while moving the table along the transport path, the first and second nozzles are fixed and dried using the existing table transport equipment toward the table being transported. It is preferable to spray the prevention liquid and the buffer solution because the drying prevention liquid and the buffer solution can be sprayed without adding a nozzle moving facility.

  According to the glass substrate polishing method and polishing apparatus of the present invention, it is preferable that the drying preventing liquid and the buffer liquid are the same liquid.

  According to the glass substrate polishing method and polishing apparatus of the present invention, the liquid is preferably a polyhydric alcohol.

  According to the present invention, polyhydric alcohols are preferred when the same liquid is used as the anti-drying solution and the buffer solution. In addition, water can be illustrated as a liquid for drying prevention. However, since polyhydric alcohol has a higher drying preventing effect than water, polyhydric alcohol is preferred. Polyhydric alcohol is also suitable as an anti-contamination liquid for the edge of the glass substrate by the polishing liquid.

  In addition, the kind of polyhydric alcohol is not specifically limited, Specifically, glycerol, polyethyleneglycol, ethylene glycol, propylene glycol, diethylene glycol etc. are illustrated. Further, the anti-drying solution and the buffer solution may be composed of two or more kinds of polyhydric alcohols, and may be a polyhydric alcohol aqueous solution by mixing polyhydric alcohol and water.

  According to the glass substrate polishing method of the present invention, a plurality of the same common nozzles that share the first nozzle and the second nozzle are arranged above the table in a direction orthogonal to the table, The liquid is preferably sprayed from the common nozzle toward the table.

  According to the glass substrate polishing apparatus of the present invention, a plurality of the same common nozzles that share the first nozzle and the second nozzle are arranged above the table in a direction orthogonal to the table, It is preferable that the liquid is sprayed from the common nozzle toward the table.

  According to the present invention, the same liquid such as polyhydric alcohol sprayed from a plurality of common nozzles is applied to the area of the table where the entire area of the non-polished surface of the glass substrate is adsorbed and fixed, and the non-polished glass substrate The liquid is applied to the area of the table where the entire edge of the surface is suction fixed. Since the first and second nozzles can be shared by using the same liquid in this way, the liquid supply system for the nozzles can be simplified. Therefore, this invention can comprise a liquid spraying part with simple equipment.

  In the present invention, a liquid spraying process for spraying the anti-drying liquid and the buffer liquid toward the table is provided. Instead of this process, the anti-drying liquid is applied to the entire non-polished surface of the glass substrate. And you may provide the process of apply | coating a buffer solution to the edge of the said non-polishing surface.

  According to the method and apparatus for polishing a glass substrate according to the present invention, the anti-drying liquid and the buffer solution are sprayed from the liquid spray portion toward the table, so that the edge of the non-polished surface of the glass substrate is contaminated by the polishing liquid. In addition, the non-polished surface of the glass substrate can be satisfactorily fixed to the table by suction.

FIG. 1 is a plan view showing an overall configuration of a glass substrate polishing apparatus according to an embodiment. FIG. 2 is a front view of the configuration of the liquid spray unit as viewed from the downstream side of the table transport path. FIG. 3 is a plan view of the liquid spray section shown in FIG. FIG. 4 is an explanatory view showing a region where the buffer solution is sprayed by the second nozzle group and a region where the buffer solution is not sprayed. FIG. 5 is a timing chart showing the opening / closing operation of the solenoid valves of the second nozzle group. FIG. 6 is a front view of the configuration of the liquid spray unit according to another embodiment as viewed from the downstream side of the table transport path. FIG. 7 is a plan view of the liquid spray section shown in FIG. FIG. 8 is a block diagram showing a liquid piping system for supplying polyhydric alcohol to a common nozzle. FIG. 9 is a block diagram showing an air piping system for ON-OFF control of the injection of the polyhydric alcohol supplied to the common nozzle. FIG. 10 is an explanatory diagram showing an area where the speed of the table in the liquid spraying unit is changed. FIG. 11 is a timing chart showing the speed of the table in the liquid spray section.

  Hereinafter, preferred embodiments of a glass substrate polishing method and polishing apparatus according to embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a plan view showing an overall configuration of a glass substrate polishing apparatus 10 according to an embodiment. In FIG. 1, the table transport path of the rectangular table 12 that sucks and fixes the non-polished surface of the rectangular glass substrate G is indicated by an arrow.

  In the table transport path, a liquid spraying section 14, a glass substrate fixing section 16, and a polishing section 18 are sequentially arranged from the upstream side to the downstream side of the table transport path. Further, on the downstream side of the polishing unit 18, a glass substrate removing portion (not shown) and a table cleaning unit are provided.

  In the polishing unit 18, the glass substrate G is a plurality of polishing tools arranged along the table transport path while being transported along the table transport path with the non-polished surface of the glass substrate G being sucked and fixed to the table 12. Is continuously polished. At this time, the polishing surface is polished by the rotating polishing tool while the polishing liquid is supplied to the polishing surface of the glass substrate G. And the glass substrate G is manufactured in the thin plate shape which satisfied the flatness etc. which are requested | required by the glass substrate for FPD in the exit of the grinding | polishing part 18. FIG. The number of polishing tools arranged in the polishing unit 18 is not limited to a plurality. That is, one polishing tool may be used according to the size of the glass substrate G.

  The polished glass substrate G is unloaded from the polishing unit 18 and loaded into the glass substrate removal described above, where it is removed from the table 12. Then, the table 12 from which the glass substrate G has been removed is cleaned by the cleaning liquid while passing through the above-described table cleaning unit, and is re-transported to the liquid spraying unit 14 in order to suck and fix the next glass substrate G. As described above, the table transport path is configured in a loop shape so that the table 12 passes through the liquid spraying unit 14, the glass substrate fixing unit 16, the polishing unit 18, the outside of the glass substrate, and the table cleaning unit in this order.

  A plurality of tables 12 according to the embodiment are arranged on the table transport path, and two glass substrates G are adsorbed and fixed to one table 12. Note that the number of tables 12 arranged on the table transport path is not limited, and the number of glass substrates G attracted and fixed to the table 12 is not limited to two. That is, depending on the size of the glass substrate G, it may be one or three or more.

  FIG. 2 is a front view of the configuration of the liquid spraying unit 14 as viewed from the downstream side of the table transport path. That is, the table 12 is transported from the back of the sheet of FIG. 2 toward the front. FIG. 3 is a plan view of the liquid spray unit 14. In FIG. 3, a two-dot chain line shown on the table 12 indicates an edge of the glass substrate G that is positioned on the table 12 and fixed by suction.

  As shown in FIG. 2, a first nozzle group 22 including four first nozzles 20a, 20b, 20c, and 20d for spraying the drying preventing liquid on the adsorption area on the table is disposed above the table conveyance path. Has been. These first nozzles 20a to 20d are fixed to a gantry (not shown) above the table 12 in a direction orthogonal to the table transport path, and are provided with a drying preventing liquid supply unit (not provided) via the liquid supply system 24. (Shown). Drying prevention liquid sprayed from the first nozzles 20a to 20d prevents drying in the suction region 26 where the entire non-polished surface of the glass substrate G surrounded by the two-dot chain line shown in FIG. A working solution is applied. In addition, although the spraying area | region of the drying prevention liquid may be the whole surface of the table 12, the adsorption | suction area | region 26 is preferable from a viewpoint of saving the drying prevention liquid.

  The first nozzles 20a to 20d are connected to the drying prevention liquid supply unit via an electromagnetic valve. The solenoid valve is intermittently opened and closed by a control unit (not shown) so that the suction region 26 is opened only when the suction region 26 passes under the first nozzles 20a to 20d. Therefore, the anti-drying liquid is applied only to the suction region 26 by the first nozzles 20a to 20d.

  Further, 14 second nozzles 28a, 28b, 28c for spraying the buffer solution onto the area where the edge of the non-polished surface of the glass substrate G is adsorbed and fixed to the table 12 are provided above the table transport path. A second nozzle group 30 including 28d, 28e, 28f, 28g, 28h, 28i, 28j, 28k, 28l, 28m, and 28n is disposed. These second nozzles 28 a to 28 n are fixed to a gantry (not shown) above the table 12 in a direction orthogonal to the table transport path, and a buffer solution supply unit (not shown) via the liquid supply system 32. It is connected to. The buffer solution is a liquid for preventing contamination of the non-polished surface of the glass substrate G by the polishing solution.

  Among the second nozzles 28a to 28n, the two second nozzles 28a and 28n disposed on both sides pass through the short side portions facing each other among the edge portions of the glass substrate G indicated by a two-dot chain line in FIG. The regions 34A and 34B are arranged to face each other. The two second nozzles 28a and 28n are connected to the buffer solution supply unit via electromagnetic valves. This solenoid valve is intermittently opened and closed by a control unit (not shown) so that the regions 34A and 34B are opened under the two second nozzles 28a and 28n only during passage. Accordingly, the buffer solution is applied only to the regions 34A and 34B by the two second nozzles 28a and 28n.

  On the other hand, the other nozzles 28b to 28m other than the second nozzle 28a and the nozzle 28n are opposed to the regions 36A and 36B through which the opposite long sides pass among the edges of the glass substrate G indicated by a two-dot chain line in FIG. Has been placed. Moreover, these 2nd nozzles 28b-28m are connected with the said buffer supply part via the solenoid valve. This solenoid valve is intermittently opened and closed by a control unit (not shown) so that the regions 36A and 36B are opened under the second nozzles 28b to 28m only during passage.

  That is, the second nozzles 28b to 28m are divided into the divided areas A to E shown in FIG. 4 and the divided areas A and C corresponding to the areas 36A and 36B in FIG. While passing below 28 m, the opening / closing (ON-OFF) of the solenoid valve is controlled by the control unit so that the solenoid valve is opened (ON) as shown in FIG. Accordingly, the buffer solution is applied only to the regions 36A and 36B by the 12 second nozzles 28b to 28m.

  As described above, the anti-drying liquid is applied to the adsorption region 26 in which substantially the entire non-polished surface of the glass substrate G surrounded by the two-dot chain line in FIG. 3 is adsorbed and fixed. A buffer solution is applied to the regions 34A, 34B, 36A, 36B at the edge of the non-polished surface of the glass substrate G shown. In addition, since the first nozzle group 22 is disposed on the upstream side of the table transport path and the second nozzle group 30 is disposed on the downstream side of the table transport path, in the regions 34A, 34B, 36A, and 36B, A buffer solution is applied to the upper layer of the anti-drying solution.

  As described above, the table 12 to which the drying preventing liquid and the buffer solution are applied is conveyed along the table conveyance path to the glass substrate fixing unit 16 shown in FIG. Here, the non-polished surface of the glass substrate G is positioned at the position of the glass substrate G indicated by a two-dot chain line in FIG.

  The two glass substrates G attracted and fixed to the table 12 are transported along the table transport path to the polishing unit 18 of FIG. 1, where the polishing surface of the glass substrate G is continuously formed by a plurality of polishing tools as described above. Polished.

  Next, the operation of the glass substrate polishing apparatus configured as described above will be described.

  First, the empty table 12 is conveyed to the liquid spraying part 14 along a table conveyance path. Then, while transporting the table 12 along the table transport path, the drying prevention liquid is sprayed from the first nozzle group 22 toward the table 12, and the drying prevention liquid is applied to the adsorption region 26 of FIG. . Then, the buffer solution is sprayed from the second nozzle group 30 toward the table 12, and the buffer solution is applied to the regions 34 </ b> A, 34 </ b> B, 36 </ b> A, 36 </ b> B on the edge of the non-polished surface of the glass substrate G.

  Next, the table 12 is transported to the glass substrate fixing unit 16 where the entire non-polished surface of the glass substrate G is adsorbed and fixed to the table 12 via the drying preventing liquid, and the glass substrate G is non-coated. The entire edge of the polishing surface is adsorbed and fixed to the table 12 via the buffer solution.

  Next, the table 12 is conveyed to the polishing unit 18 where the polishing surface is polished by a polishing tool while supplying a polishing liquid to the polishing surface of the glass substrate G. During this polishing, the edge of the non-polished surface of the glass substrate G is protected by the buffer solution, so that the edge is not contaminated by the polishing solution.

  As described above, according to the polishing apparatus 10 according to the above-described embodiment, the liquid spray unit 14 is provided in the table transport path, and drying is prevented from the first nozzle group 22 toward the table 12 being transported along the table transport path. While spraying the working solution, the buffer solution is sprayed from the second nozzle group 30.

  Therefore, according to this glass substrate polishing apparatus 10, in the glass substrate polishing apparatus 10 that polishes the glass substrate G having the non-polished surface adsorbed and fixed to the table 12 while transporting the table 12, the glass substrate by the polishing liquid is used. Contamination of the edge of the non-polished surface of G can be prevented, and the non-polished surface of the glass substrate G can be satisfactorily fixed to the table 12 by suction.

  Examples of the anti-drying solution include polyhydric alcohol, polyhydric alcohol aqueous solution, and water, and examples of the buffer solution include polyhydric alcohol and polyhydric alcohol aqueous solution.

  6-11 is a figure for demonstrating other embodiment of a liquid spraying part. FIG. 6 is a front view of the configuration of the liquid spray unit 40 according to another embodiment as viewed from the downstream side of the table transport path. FIG. 7 is a plan view of the liquid spray unit 40. A two-dot chain line shown on the table 12 in FIG. 7 indicates an edge portion of the glass substrate G that is positioned on the table 12 and fixed by suction.

  In the liquid spraying section 40 shown in FIGS. 6 and 7, the polyhydric alcohol that is the same liquid as the liquid for preventing drying and the buffer solution is sprayed. In addition, the liquid spraying unit 40 includes fourteen common nozzles 42a, 42b, 42c, 42d, 42e, 42f, 42g, 42h, 42i, 42j having the same configuration in which the first nozzle and the second nozzle are made common. A common nozzle group 44 including 42k, 42l, 42m, and 42n is provided. These common nozzles 42a to 42n are fixed to a gantry (not shown) above the table 12 in a direction perpendicular to the table transport path, and are connected to the polyhydric alcohol supply unit shown in FIG. 48. 8 shows a liquid piping system for supplying polyhydric alcohol to the common nozzles 42a to 42n, and FIG. 9 shows that the injection of the polyhydric alcohol supplied to the common nozzles 42a to 42n is ON−. An air piping system for OFF control is shown. That is, the compressed air from the pump 72 is ON / OFF controlled by the solenoid valves 52, 60, 62, and 64, and the pistons of the common nozzles 42a to 42n are operated using the compressed air thus controlled. Thus, the injection of polyhydric alcohol is ON-OFF controlled.

  Two common nozzles 42a and 42n arranged on both sides of the common nozzles 42a to 42n are regions 50A and 50B through which the opposite short sides of the edge of the glass substrate G indicated by a two-dot chain line in FIG. 7 pass. Are arranged opposite to each other. The two common nozzles 42a and 42n are connected to a polyhydric alcohol supply unit 48 through flow meters 43a and 43n, a liquid supply system 46, and a filter 78 as shown in FIG. Further, the electromagnetic valve 52 shown in FIG. 9 is intermittently opened / closed by a control unit (not shown) so that the regions 50A and 50B are opened only when passing under the two common nozzles 42a and 42n. . Accordingly, the polyhydric alcohol is applied only to the regions 50A and 50B by the two common nozzles 42a and 42n.

  On the other hand, the other common nozzles 42b to 42m excluding the common nozzle 42a and the nozzle 42n are opposed to the regions 52A and 52B through which the opposite long sides pass among the edges of the glass substrate G indicated by the two-dot chain line in FIG. Has been placed. Further, as shown in FIG. 9, the common nozzles 42b to 42m are divided into the common nozzles 42b to 42e, the common nozzles 42f to 42i, and the common nozzles 42j to 42m. Is configured. These common nozzle subgroups 54, 56 and 58 are connected to a pump 72 via solenoid valves 60, 62 and 64, and as shown in FIG. 8, flow meters 43b to 43m, a liquid supply system 46 and a filter 78 are connected. It is connected to the polyhydric alcohol supply unit 48 through the via. The electromagnetic valves 60, 62, and 64 are opened only when the adsorption region 66 of the glass substrate G surrounded by a two-dot chain line in FIG. 7 including the regions 52A and 52B is passing under the 12 common nozzles 42b to 42m. As described above, intermittent opening / closing control is performed by a control unit (not shown).

  As shown in FIG. 8, the polyhydric alcohol supply unit 48 includes a tank 70 in which polyhydric alcohol is stored, a pump (not shown) that supplies compressed air to the tank 70, and a flow rate that measures the amount of compressed air supplied to the tank 70. It comprises a total of 74 and a check valve 76 that prevents the backflow of polyhydric alcohol fed from the tank 70 to the liquid supply system 46.

  According to the polyhydric alcohol supply unit 48, by supplying compressed air from the pump to the tank 70, the polyhydric alcohol in the tank 70 is sent from the check valve 76 to the liquid supply system 46 through the filter 78. To be liquidated. Note that two tanks 70, flow meters 74, and check valves 76 can be provided side by side as shown in FIG.

  By the way, in order to exhibit the function of the buffer solution that prevents the edge of the non-polished surface of the glass substrate from being contaminated by the polishing solution, the amount of polyhydric alcohol applied to the table 12 as the buffer solution (per unit area). The coating amount) is preferably set to be larger than the amount of polyhydric alcohol (coating amount per unit area) applied as the anti-drying solution.

  In other words, if the transport speed of the table 12 is constant and the polyhydric alcohol spray amounts from all the common nozzles 42a to 42n are the same, the above setting is impossible. In addition, if the polyhydric alcohol spray amount from all the common nozzles 42a to 42n is set to the application amount as a buffer solution sprayed to the regions 50A, 50B, 52A, 52B corresponding to the edges, the region 66 Excess polyhydric alcohol is applied, and polyhydric alcohol is wasted.

  Therefore, in the liquid spray unit 40 of the embodiment, the spray amount from the 12 nozzles 42b to 42m excluding the common nozzles 42a and 42n on both sides is set to the spray amount as a buffer solution sprayed to the regions 52A and 52B. doing. Further, the spray amount from the common nozzles 42a and 42n on both sides is set slightly larger than the spray amount from the other common nozzles 42b to 42m, and the conveying speed of the table 12 is controlled as follows. Here, the slightly larger amount means that the spray amount from the common nozzles 42a and 42n is 100 times or more than the spray amount from the other common nozzles 42b to 42m.

  That is, in the divided areas A to E shown in FIG. 10, the divided areas A and C (E are the same) corresponding to the areas 52A and 52B in FIG. 7 are set to the normal table transport speed S1 as shown in FIG. 7 is set to S2, which is faster than S1, as shown in FIG.

In addition, it is preferable that the application amount as a buffer solution sprayed on the regions 50A, 50B, 52A, and 52B corresponding to the edge is 0.001 ml / cm ² , and the application amount as a buffer solution sprayed on the region 66 It is preferable that it becomes 100 times or more.

  Accordingly, the amount of polyhydric alcohol applied to the regions 52A and 52B in FIG. 7 becomes a preferable amount as a buffer solution, and the amount of polyhydric alcohol sprayed onto the region 66 is less than the preferable amount as a buffer solution. It becomes a preferable amount as a liquid for prevention. Further, although the table transport speed S2 is high, the spray amount from the common nozzles 42a and 42n on both sides is set to be slightly larger than the spray amounts from the other common nozzles 42b to 42m. The amount of polyhydric alcohol sprayed on 50B is a preferable amount as a buffer solution. Here, the slightly larger amount means that the spray amount from the common nozzles 42a and 42n is 100 times or more than the spray amount from the other common nozzles 42b to 42m.

  By using polyhydric alcohol of the same liquid as the liquid to be sprayed in this way, the first nozzle group 22 and the second nozzle group 30 shown in FIGS. 2 and 3 can be made common, so the common nozzle 42a. The liquid supply system for ˜42n can be simplified. Therefore, the liquid spraying part 40 of this embodiment becomes a simple installation compared with the liquid spraying part 14 shown in FIG. 2, FIG.

  In addition, in the liquid spraying part 40, although the conveyance speed of the table 12 was changed and the application amount of the polyhydric alcohol was controlled, it is not limited to this.

  For example, the conveying speed of the table 12 is fixed, the spray amount from the common nozzles 42a and 42n on both sides is set to an optimum amount as a buffer solution, and the spray amounts of the other 12 common nozzles 42b to 42m are controlled. That is, when the regions 52A and 52B pass below the common nozzles 42b to 42m, the spray amount is set to an optimum amount as a buffer solution, and when the region 66 passes below the common nozzles 42b to 42m. The spray amount may be set to an optimum amount as a drying preventing liquid. Such flow rate control can be achieved by using a flow rate variable valve and including a control unit that controls the opening of the flow rate variable valve according to the travel position of the table 12.

  In the embodiment, the configuration is described in which the table is a movable type and the first and second nozzles are fixed types. However, the present invention is not limited to this. That is, the table is a fixed type, the first and second nozzles are movable types, and the drying prevention liquid and buffer solution are sprayed onto the table while moving the first and second nozzles above the fixed table. A desired spray pattern may be formed on the table.

  On the other hand, the table and the first and second nozzles may be fixed. In this case, in order to form a desired spray pattern on the table, a mask member such as a metal mask is disposed above the table and a common liquid (polyhydric alcohol) is sprayed on the entire table. Thereby, a spray pattern can be formed on a table. Moreover, a desired spray pattern can be formed on the table also by adjusting the arrangement positions of the first nozzle and the second nozzle above the table in accordance with the spray pattern.

  G ... Glass substrate, 10 ... Glass substrate polishing apparatus, 12 ... Table, 14 ... Liquid spraying part, 16 ... Glass substrate fixing part, 18 ... Polishing part, 20a-20d ... First nozzle, 22 ... First nozzle Group, 24 ... liquid supply system, 26 ... adsorption region, 28a to 28n ... second nozzle, 30 ... second nozzle group, 32 ... liquid supply system, 34A, 34B ... region, 36A, 36B ... region, 40 ... Liquid spray section, 42a to 42n ... common nozzle, 43a to 43n ... flow meter, 44 ... common nozzle group, 46 ... liquid supply system, 48 ... polyhydric alcohol supply section, 50A, 50B ... area, 52 ... solenoid valve, 54 , 56, 58 ... common nozzle subgroup, 60, 62, 64 ... solenoid valve, 66 ... adsorption area, 70 ... tank, 72 ... pump, 74 ... flow meter, 76 ... check valve, 78 ... filter

Claims (10)

The anti-drying liquid is sprayed from the first nozzle to a region where the entire non-polished surface of the glass substrate of the table is adsorbed and fixed toward the table for adsorbing and fixing the non-abrasive surface of the glass substrate, and then the table On the other hand, a liquid spraying step of spraying a buffer solution from a second nozzle onto a region where the edge of the non-polished surface of the glass substrate of the table is adsorbed and fixed, the buffer per unit area of the table A liquid spraying step in which the liquid application amount is set to be larger than the application amount of the anti-drying liquid per unit area of the table ;
The entire area of the non-polished surface of the glass substrate is adsorbed and fixed to the table via the anti-drying liquid, and the edge of the non-polished surface of the glass substrate is adsorbed and fixed to the table via the buffer solution. A glass substrate fixing process;
A polishing step of polishing the polishing surface with a polishing tool while supplying a polishing liquid to the polishing surface of the glass substrate on which a non-polishing surface is adsorbed and fixed to the table;
A method for polishing a glass substrate comprising:   The liquid spraying step sprays the anti-drying liquid from the first nozzle while relatively moving at least one of the table and the first and second nozzles, and from the second nozzle. The glass substrate polishing method according to claim 1, wherein the buffer solution is sprayed.   The glass substrate polishing method according to claim 2, wherein the drying preventing liquid and the buffer solution are the same liquid.   The glass substrate polishing method according to claim 3, wherein the liquid is a polyhydric alcohol.   A plurality of the same common nozzles that share the first nozzle and the second nozzle are arranged above the table in a direction orthogonal to the relative movement direction of the table, and the liquid is discharged from the common nozzle. The glass substrate polishing method according to claim 3, wherein the glass substrate is sprayed toward the table. A table for adsorbing and fixing the non-polished surface of the glass substrate;
A first nozzle that sprays an anti-drying liquid onto a region where the entire area of the non-polished surface of the glass substrate of the table is adsorbed and fixed toward the table, and the glass substrate of the table with respect to the table And a second nozzle that sprays a buffer solution onto a region where the edge of the polishing surface is adsorbed and fixed , wherein the application amount of the buffer solution per unit area of the table is A liquid spray portion set larger than the coating amount of the drying preventing liquid per unit area ;
The entire area of the non-polished surface of the glass substrate is adsorbed and fixed to the table via the anti-drying liquid, and the edge of the non-polished surface of the glass substrate is adsorbed and fixed to the table via the buffer solution. A glass substrate fixing part;
A polishing unit that polishes the polishing surface with a polishing tool while supplying a polishing liquid to the polishing surface of the glass substrate on which a non-polishing surface is fixed by suction to the table;
A glass substrate polishing apparatus comprising:   The liquid spraying unit sprays the anti-drying liquid from the first nozzle while relatively moving at least one of the table and the first and second nozzles, and from the second nozzle. The glass substrate polishing apparatus according to claim 6, wherein the buffer solution is sprayed.   The glass substrate polishing apparatus according to claim 7, wherein the drying prevention liquid and the buffer solution are the same liquid.   The glass substrate polishing apparatus according to claim 8, wherein the liquid is a polyhydric alcohol.   A plurality of the same common nozzles that share the first nozzle and the second nozzle are arranged above the table in a direction perpendicular to the relative movement direction of the table, and the liquid is discharged from the common nozzle to the liquid. The glass substrate polishing apparatus according to claim 8, wherein the glass substrate is sprayed toward the table.