JP2016007668A - Polishing method and polishing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polishing method capable of uniformly polishing an apex part of a mesa part, even in an imprint circuit board.SOLUTION: A circuit board B forms a mesa part 1 on a surface, and when polishing an upper surface 2 of the mesa part 1 of the circuit board B for forming a recess 3 on a reverse surface of an area including a position for forming the mesa part 1, the upper surface is polished by allowing a polishing pad 10 to abut on the upper surface 2 while pressing a position of the mesa part 1 from the reverse surface side by this fixed pressurizing tool 21 by using the pressurizing tool 21 fixed to the reverse surface of the circuit board B including the recess 3 and pressing the position of the mesa part 1 from the reverse surface side.

Description

  The present invention belongs to a technical field of a polishing method and a polishing apparatus, and more particularly, to a technical field of a polishing method and a polishing apparatus for polishing a surface of a substrate for manufacturing a semiconductor device.

  In general, a so-called photolithography technique is often used in manufacturing a semiconductor device including a semiconductor circuit. In the manufacturing method using this photolithography technique, a substrate on which a circuit pattern to be a mold is formed is used.

  On the other hand, such a substrate is reused by semiconductor devices having different circuit patterns. For this reason, the surface of the substrate on which a necessary circuit pattern is once formed is polished into a mirror surface and another circuit pattern is re-formed. As a prior art document relating to the surface polishing of such a substrate, for example, there is the following non-patent document 1.

  On the other hand, in recent years, semiconductor devices are sometimes manufactured by so-called imprint technology. In general, this imprint technology uses a circuit pattern by pressing an imprint mold with a nanometer-size fine circuit pattern (uneven circuit pattern) formed on the surface in advance against a transfer material such as resin applied to the surface to be processed. Is a technique for processing a substrate to be processed using a transfer material on which the circuit pattern is formed as a mask. In this case, once the imprint mold is produced, the nanostructure can be easily and repeatedly molded, which is economical as a whole.

  Further, as an imprint mold having the fine circuit pattern used in the imprint technique, a mold manufactured by electron beam lithography has been conventionally known. As a prior art document regarding this electron beam lithography, for example, the following Non-Patent Document 2 can be cited. Specifically, in electron beam lithography, a resist pattern is formed on one surface of a mold substrate using an electron beam lithography apparatus, and the mold substrate is dry-etched using the resist pattern as a mask, thereby imprinting. A mold is produced. In the imprint mold produced in this way, production by the electron beam drawing apparatus (drawing of the resist pattern) in the production process requires a huge amount of time, and the production cost is very high. In addition, if a resist pattern formed using an electron beam lithography system is used repeatedly in the transfer process, defects may occur in the fine circuit pattern formed on the material to be transferred (imprinting resin, etc.) The fine circuit pattern of the mold may be damaged.

  In this way, when a fine circuit pattern defect formed on the transfer material or an imprint mold fine circuit pattern is damaged, a new imprint created by electron beam lithography is used each time. If it replaces | exchanges to a mold, it will lead to the cost increase of products, such as a semiconductor device manufactured through nanoimprint technology.

  Therefore, when performing nanoimprint technology on an industrial scale, generally, an imprint mold produced by electron beam lithography is used as a master mold, and a fine circuit pattern obtained by inverting the fine circuit pattern of the master mold using the master mold is used. Usually, a large number of replica molds having a circuit pattern are produced, and the replica molds are used as imprint molds in nanoimprint technology.

  In these master molds or replica molds (hereinafter referred to as imprint substrates), in order to prevent interference with an adjacent transfer pattern, a base-like convex portion is formed, and a transfer circuit is formed on the top thereof. Pattern molds may be formed. In addition, when a substrate for imprinting, particularly a 6-inch square and 0.25-inch thick substrate used for semiconductor manufacturing is used as a mold, a “dent” is formed on the back side of the convex portion on the substrate. Is known to form. This recess is formed by cutting the substrate from the back side to form a recess of a predetermined size at that position. As a prior art document regarding this hollow, the following patent document 1 is mentioned, for example. Due to the depression, the substrate is easily bent, and the residual gas in the transfer region can be pushed out by controlling the contact surface between the mold and the transferred member during transfer of the circuit pattern. Furthermore, when the master mold and the replica mold are produced on the 6-inch square and 0.25-inch thick substrates, respectively, if the depression is not formed, the size of the bend is small and a beautiful circuit pattern is formed. I can't. Further, by forming a recess in at least one of the master mold and the replica mold, the substrate can be easily bent, and the substrate can be easily peeled off from the transferred circuit pattern. Since the replica mold is used as an imprint mold in the next transfer step, it is desirable to form a recess in the replica mold. Here, in the following description, the trapezoidal convex portion is referred to as a “mesa portion”.

Japanese Patent No. 5139421

“Introductory Photomask Technology”, pp. 84-86, Isao Tanabe et al., Industrial Research Co., Ltd., first published on December 15, 2006 “First nanoimprint technology”, pages 172 to 179, Jun Taniguchi et al., Industrial Research Co., Ltd., published in December 2005

  However, when the polishing pad for polishing is brought into contact with the top portion in order to polish the top portion of the mesa portion of the imprint substrate using the technique disclosed in Non-Patent Document 1, a depression ( Due to the presence of the space, the substrate is bent in the back side direction by the contact pressure, and as a result, the top of the mesa portion cannot be uniformly polished (more specifically, the periphery of the top of the mesa portion) There is a problem that the portion is polished deeper than the central portion, and the top does not become a uniform flat surface). This problem causes a more serious problem such as a decrease in manufacturing yield as the semiconductor device is miniaturized and the degree of integration is improved.

  Therefore, the present invention has been made in view of the above-described problems, and the problem is a polishing method capable of uniformly polishing the top of the mesa portion even if it is a substrate for imprinting. It is to provide a polishing apparatus.

  In order to solve the above-described problem, the invention according to claim 1 is a substrate having a convex portion formed on a surface thereof, wherein the region including the position of the surface on which the convex portion is formed is the substrate. A polishing method for polishing the top of the convex portion of a substrate that has been thinned so as to bend the substrate, and a pressing means such as a pressure jig is fixed to the back surface of the substrate including the thinned region. A fixing step, and a polishing step of polishing the top by bringing a polishing means such as a polishing pad into contact with the top while pressing the position of the convex portion from the back side using the fixed pressing means; including.

  According to the first aspect of the present invention, when polishing the top of the convex portion in the substrate where the region including the position where the convex portion is formed is thinned, the back surface of the substrate including the thinned region The pressing means is fixed to the surface, and the top is polished by bringing the polishing means into contact while pressing the position of the convex portion from the back side of the substrate using the fixed pressing means. Therefore, even if the substrate including the position where the convex portion is formed is thinned by abutting the polishing means while pressing from the back side to polish the top portion of the convex portion, the convex portion The top of the part can be uniformly polished.

  In order to solve the above problems, the invention according to claim 2 is the polishing method according to claim 1, wherein the polishing step includes a shape inspection step of inspecting a surface shape of the top portion to be polished; An adjustment step of adjusting the pressing force by the pressing means based on the result of the shape inspection, and repeating the shape inspection step and the adjustment step until the surface shape is in a preset state, Configured to polish the top.

  According to invention of Claim 2, in addition to the effect | action of invention of Claim 1, a shape inspection process and an adjustment process are included in the grinding | polishing process, and the surface shape of the top part of a convex part is a predetermined state Since it grind | polishes repeating a shape test process and an adjustment process until it becomes, it can grind | polish the top part of a convex part more precisely.

  In order to solve the above-mentioned problem, the invention according to claim 3 is the polishing method according to claim 1 or 2, wherein the pressing means seals the thinned region of the back surface. Sealing means such as a groove; and gas introduction means such as a cock that introduces gas into the sealed space and presses the position of the convex portion from the back side.

  According to invention of Claim 3, in addition to the effect | action of invention of Claim 1 or Claim 2, since a press means is equipped with a sealing means and a gas introduction means, it is uniform from the back side by the pressure of gas. By being able to press the convex part, the top part of the convex part can be more uniformly polished.

  In order to solve the above-mentioned problem, the invention according to claim 4 is the polishing method according to claim 1 or 2, wherein the pressing means is brought into contact with the thinned region of the back surface. And a contact pressing means such as a pressing plate for pressing the area.

  According to invention of Claim 4, in addition to the effect | action of invention of Claim 1 or Claim 2, since a press means is provided with contact | abutting press means, a pressing force can be adjusted flexibly and convex parts can be adjusted. The top can be polished more uniformly.

  In order to solve the above-mentioned problem, the invention according to claim 5 is a substrate in which a convex portion is formed on a surface, and a region including the position of the surface on which the convex portion is formed is the substrate. A polishing apparatus for polishing the top of the convex portion of the substrate that is thinned to bend, and is fixed to a polishing means such as a polishing pad and the back surface of the substrate including the thinned region, While pressing the position of the convex part from the back side by using a pressing means such as a pressure jig for pressing the position of the convex part from the back side and the fixed pressing means, the polishing is applied to the top part. Polishing control means such as a cock for contacting the means and polishing the top.

  According to the fifth aspect of the present invention, when polishing the top of the convex portion in the substrate where the region including the position where the convex portion is formed is thinned, the back surface of the substrate including the thinned region The pressing means is fixed to the top, and the top is polished by contacting the polishing means while pressing the position of the convex portion from the back side of the substrate using the fixed pressing means. Therefore, even if the substrate including the position where the convex portion is formed is thinned by abutting the polishing means while pressing from the back side to polish the top portion of the convex portion, the convex portion The top of the part can be uniformly polished.

  In order to solve the above-mentioned problem, the invention according to claim 6 is the polishing apparatus according to claim 5, wherein the pressing means seals a suction groove or the like that seals the thinned region of the back surface. Means and gas introducing means such as a cock for introducing gas into the sealed space and pressing the position of the convex portion from the back surface side.

  According to invention of Claim 6, in addition to the effect | action of invention of Claim 5, since a press means is equipped with a sealing means and a gas introduction means, it can press a convex part uniformly by the pressure of gas. By being able to do, the top part of a convex part can be grind | polished more uniformly.

  In order to solve the above-mentioned problem, the invention according to claim 7 is the polishing apparatus according to claim 6, wherein the gas introduction means maintains the pressing force by the introduced gas after the introduction of the gas. Maintenance means such as a cock is provided.

  According to the invention described in claim 7, in addition to the action of the invention described in claim 6, since the gas introducing means includes the maintaining means for maintaining the pressing force by the gas, the degree of freedom in use as a polishing apparatus. Can be increased.

  In order to solve the above-mentioned problem, the invention according to claim 8 is the polishing apparatus according to claim 5, wherein the pressing means is brought into contact with the thinned area on the back surface to thereby reduce the area. A contact pressing means such as a pressing plate for pressing is provided.

  According to the invention described in claim 8, in addition to the action of the invention described in claim 5, since the pressing means includes the contact pressing means, the pressing force is adjusted flexibly so that the top of the convex portion is more uniform. Can be polished.

  According to the present invention, when polishing the top of the convex portion in the substrate where the region including the position where the convex portion is formed is thinned, the pressing means is fixed to the back surface of the substrate including the thinned region. Then, using the fixed pressing means, the top portion is polished by abutting the polishing means while pressing the position of the convex portion from the back side of the substrate.

  Accordingly, even if the substrate including the position where the convex portion is formed is thinned by polishing the top of the convex portion by pressing the polishing means while pressing from the back side, the convex portion The top of the part can be uniformly polished.

It is a figure which shows the structure of the grinding | polishing apparatus which concerns on 1st Embodiment, (a) is side sectional drawing which shows the structure of the said grinding | polishing apparatus, (b) is the 1st of the structure for the vacuum suction in a pressurization jig | tool. It is a figure which shows an example, (c) is a figure which shows the 2nd example of the structure for the said vacuum suction. It is a flowchart which shows the grinding | polishing operation | work for reproduction | regeneration, etc. which concern on 1st Embodiment, (a) is a flowchart which shows the operation | work of a data acquisition stage, (b) is a graph which shows the relationship between a pressure and the height difference after grinding | polishing. Yes, (c) is a flowchart showing the reclaiming polishing operation. It is a figure which shows the effect of the grinding | polishing operation | work for regeneration which concerns on 1st Embodiment, (a) is a figure which shows the effect of the said grinding | polishing work for reproduction | regeneration, (b) is a figure explaining a prior art. It is side surface sectional drawing which shows the structure of the grinding | polishing apparatus which concerns on 2nd Embodiment.

  Next, modes for carrying out the present invention will be described based on the drawings. In addition, each embodiment described below is an embodiment when the present invention is applied to a polishing apparatus that polishes, for example, the upper surface of a mesa portion of a substrate for nanoimprinting for regeneration.

(I) First Embodiment First, a first embodiment according to the present invention will be described with reference to FIGS. FIG. 1 is a view showing the configuration of the polishing apparatus according to the first embodiment, FIG. 2 is a flowchart showing the regeneration polishing work according to the first embodiment, and FIG. 3 shows the regeneration polishing work. It is a figure which shows an effect etc.

  As shown in FIG. 1, the polishing apparatus 100 according to the first embodiment is suitable for a process of a photomask having a 6-inch square and a thickness of 0.25 inch, and has a 6-inch square and a thickness of 0.25 inch for nanoimprinting. This is a polishing apparatus for polishing a top surface 2 of a trapezoidal (rectangular shape in plan view) mesa portion 1 formed on the surface of a quartz substrate B with a polishing pad 10 that is fixed to a rotating shaft 11 and rotates. On the back side of the surface area including the position of the mesa portion 1 of the substrate B, a recess 3 is formed for bending the substrate B when it is peeled off from the circuit pattern. The recess 3 is, for example, a cylindrical recess as a whole. The polishing pad 10 corresponds to an example of “polishing means” according to the present invention.

  The polishing apparatus 100 includes a pressing jig 21 that surrounds the outer frame 20, the base 24, and a region including the recess 3 on the back surface of the substrate B and is vacuum-adsorbed to the substrate B. At the periphery of the pressure jig 21, a circumferential suction groove 22 for vacuum-sucking the pressure jig 21 to the outside of the region on the back side of the substrate B, and the inside of the suction groove 22 And a seal 23 for maintaining the degree of vacuum. The inside of the suction groove 22 including these seals 23 is evacuated (more specifically, for example, the degree of vacuum is about −80 kilopascals), so that the pressurizing jig 21 of the substrate B surrounding the depression 3 is formed. It is vacuum-adsorbed on the back side. The pressurizing jig 21 corresponds to an example of a “pressing unit” according to the present invention, and the suction groove 22 and the seal 23 correspond to an example of a “sealing unit” according to the present invention.

  Here, a configuration for increasing the degree of vacuum in the suction groove 22 will be illustrated. First, as illustrated in FIG. 1B, a cross-shaped groove 31 that communicates with the suction groove 22 and is not opened is formed in a space AR (including the depression 3) described later, and the groove 31 intersects. A suction port 30 is provided in the vicinity of the position where the pressure is applied, and the gas in the groove 31 and the suction groove 22 is sucked out from the suction port 30, so that the pressing jig 21 can be attracted to the back surface of the substrate B with uniform suction force. At the same time, it is possible to prevent unevenness due to its own weight and to apply an equal load. In addition, as illustrated in FIG. 1C, for example, three dummy holes 41 and suction ports 40 (the dummy holes 41 and the suction ports 40 communicate with the space AR) at equal distance positions in the suction groove 22. In the case illustrated in FIG. 1B, a cock (not shown) having the same weight is attached to the dummy hole 41 and the suction port 40 and the gas in the suction groove 22 is sucked out from the suction port 40. In the same manner as above, the bias due to its own weight can be prevented, and the pressing jig 21 can be adsorbed to the back surface of the substrate B with a uniform adsorbing force.

  On the other hand, the pressurizing jig 21 is vacuum-adsorbed to the substrate B including the recess 3 at a position facing the recess 3 surrounded by the suction groove 22 of the pressurizing jig 21. Thus, a concave portion 27 constituting the space AR is formed. In the vicinity of the center of the recess 27, a pressure hole 28 for feeding air, for example, into the space AR is formed by connecting the external hose 26 via the cock 25. With this structure, the cock 25 is opened while the pressure jig 21 is vacuum-adsorbed on the substrate B, air is sent from the external hose 26 into the space AR through the pressure hole 28, and then the cock 25 is closed. Then, the air pressure in the space AR is increased, whereby the mesa portion 1 of the substrate B is pressed from the back side (the side where the recess 3 is formed), and the upper surface 2 of the mesa portion 1 is uniformly pressed against the polishing pad 10. At this time, the cock 25 corresponds to an example of a “gas introduction unit”, an example of a “polishing control unit”, and an example of a “maintaining unit” according to the present invention.

  Next, the regenerative polishing work according to the first embodiment will be specifically described with reference to FIGS.

  As shown in FIG. 2A and FIG. 2C, the regenerative polishing work according to the first embodiment is performed by increasing the air pressure in the space AR and pressing the mesa portion 1 of the substrate B from the back side. A data acquisition stage (see FIG. 2A) for obtaining the relationship between the polishing amount on the upper surface 2 of the mesa unit 1 (the displacement amount of the upper surface 2) and the actual relationship using the relationship obtained in the data acquisition stage. It is divided into a polishing stage for regeneration (see FIG. 2C).

  In the data acquisition stage shown in FIG. 2A, the pressure jig 21 is first vacuum-sucked to the back surface of the substrate B (step S1), and the inside of the space AR formed by the pressure jig 21 sucked. For example, air is sent through the cock 25 and the pressure hole 28, thereby pressing the mesa unit 1 from the back side (step S2). Then, the polishing pad 10 is rotated while being pressed to grind the upper surface 2 of the mesa unit 1 (step S3), and thereafter, the surface shape (that is, flatness) of the upper surface 2 is measured by a method similar to the conventional method ( Step S4). The operation in step S3 is a so-called lapping operation. And the relationship between the flatness measured in step S4 and the pressure in the pressing in step S2 is recorded by a predetermined method. Thereafter, by determining whether or not a sufficient amount of data has been recorded for the relationship between the flatness and the pressure, it is determined whether or not to end the data acquisition step (step S5). If a sufficient amount of data has been recorded (step S5; YES), the data acquisition operation is terminated. On the other hand, if it is determined in step S5 that the data about the relationship is not yet sufficient (step S5; NO), the pressure in the pressing is changed (step S6) to obtain the necessary data, and then in step S2. Return to work.

When the operation of the data acquisition stage shown in FIG. 2A is completed, for example, the relationship illustrated in FIG. 2B is obtained. Here, as apparent from FIG. 2B, the height difference after polishing on the upper surface 2 of the mesa portion 1 changes linearly with respect to the pressure of the pressure from the back side of the mesa portion 1. Thereby, it is predicted that the pressure and the difference (that is, flatness) between the maximum grinding position and the minimum grinding position on the upper surface 2 are also substantially linear. Therefore, in the next polishing stage for regeneration, the initial value and adjustment amount of the pressure in the grinding operation are determined using the relationship shown in FIG. 2B obtained in the data acquisition stage shown in FIG. More specifically, in the case of the data illustrated in FIG. 2B, the initial value is set to 6,600 Pascals, for example, and the adjustment amount is 1 for a difference of 50 nanometers between the maximum grinding position and the minimum grinding position. 000 Pascals.

  When data as illustrated in FIG. 2B is obtained in the data acquisition stage shown in FIG. 2A, the process proceeds to the regeneration polishing stage shown in FIG. 2C.

  In the regeneration polishing stage shown in FIG. 2 (c), first, the pressurizing jig 21 is vacuum-sucked to the back surface of the substrate B (step S10) in the same manner as in step S1 in the data acquisition stage. For example, air is sent into the space AR formed by the tool 21 through the cock 25 and the pressure hole 28, thereby pressing the mesa 1 from the back side (step S11). The initial value at this time is an initial value set based on the data obtained in the data acquisition stage. Then, the polishing pad 10 is rotated while pressing with the initial value to grind the upper surface 2 of the mesa portion 1 (step S12). The operation in step S12 is a so-called wrapping operation similar to step S3 in the data acquisition stage. Thereafter, the surface shape of the upper surface 2 (that is, the flatness that is the difference between the maximum grinding position and the minimum grinding position) is measured by the same method as in step S4 in the data acquisition stage (step S13). Then, it is determined whether or not the flatness measured in step S13 is less than a preset threshold (for example, 0.1 micrometer) (step S14). In the determination of step S14, when the measured flatness is not less than the threshold value (that is, when the measured flatness is equal to or greater than the threshold value; step S14; NO), FIG. The pressure (that is, the air pressure in the space AR) in the pressing from the back side of the mesa unit 1 is adjusted by the adjustment amount based on the data illustrated in b) (step S15), and then the process returns to step S11.

  On the other hand, when the measured flatness is less than the threshold value in the determination in step S14 (step S14; YES), next, a polishing operation (so-called polishing) and a super-polishing operation (so-called super polishing) following the grinding in step S12. (Step S16), and then the surface roughness of the upper surface 2 is measured by, for example, a conventional method (Step S17). At this time, in the polishing operation or the super-polishing operation in step S16, the polishing pad 10 is changed from the grinding operation (step S12) to the polishing operation or the super-polishing operation. Then, it is determined whether or not the surface roughness measured in step S17 is less than a preset threshold value (for example, 0.2 nanometer per micrometer in root mean square) (step S18). ). If it is determined in step S18 that the measured surface roughness is not less than the threshold value (that is, greater than or equal to the threshold value; step S18; NO), the process returns to step S16 to perform further polishing or superpolishing in step S16. . At this time, the flatness of the upper surface 2 of the mesa unit 1 is determined in the grinding stage in step S12, and the mirroring is performed in step S16. Therefore, the pressure adjustment according to the first embodiment is executed only in step S15. . Depending on the state of the substrate B and the like, the pressure may be adjusted in the polishing or super-polishing stage of step S16. On the other hand, when the surface roughness measured in step S17 is less than the above threshold value (step S18; YES), after that, it is regenerated by determining whether or not to perform reclaiming polishing after replacing the substrate B. It is determined whether or not the final polishing stage is to be ended (step S19). When the final polishing stage is to be ended (step S19; YES), the regeneration polishing stage operation is ended. On the other hand, if it is determined in step S19 that the polishing operation for the next substrate B is to be continued (step S19; NO), the operation returns to step S10 and the polishing operation for the next substrate B is performed. Do.

  Next, the effect of performing the regeneration polishing work according to the first embodiment will be described with reference to FIG. FIG. 3A is a diagram three-dimensionally showing the state of the upper surface 2 of the mesa unit 1 when the regeneration polishing operation according to the first embodiment is performed, and FIG. It is a figure which illustrates three-dimensionally the state of the upper surface of a mesa part when the grinding | polishing work for reproduction | regeneration is performed.

  First, the shape of the upper surface 2 when the pressing from the back surface of the mesa unit 1 is not performed (that is, in the case of the prior art) in the regeneration polishing work according to the first embodiment is that the weight of the substrate and the jig is the mesa unit 1. By being added, the mesa portion 1 is bent toward the back side of the substrate B. For example, as illustrated in FIG. 3B, the center becomes a concave shape, and it becomes a state in which grinding or polishing cannot be performed with high planarity. On the other hand, the shape of the upper surface 2 when the pressing from the back surface of the mesa unit 1 is performed in the polishing operation for regeneration according to the first embodiment (see FIG. 2), just corrects the deflection due to the weight of the substrate and the jig. It can be seen that the flatness is remarkably improved by applying such a force, for example, as illustrated in FIG.

  As described above, according to the polishing apparatus S according to the first embodiment, the upper surface 2 of the mesa unit 1 in the substrate B in which the region including the position where the mesa unit 1 is formed is thinned by the depression 3 ( That is, when the top portion is polished, the pressure jig 21 is fixed to the back surface of the substrate B, and the position of the mesa portion 1 is pressed from the back surface side of the substrate B using the fixed pressure jig 21. The upper surface 2 is polished by bringing the polishing pad 10 into contact therewith.

  Accordingly, the substrate including the position where the mesa portion 1 is formed is thinned by polishing the upper surface 2 of the mesa portion 1 by contacting the polishing pad 10 while pressing from the back surface side of the substrate B. Even if it is B, the upper surface 2 can be uniformly polished.

  In the grinding stage, the surface shape measurement operation (step S13) and the pressure adjustment operation (step S15) are performed until the surface shape of the upper surface 2 is in a predetermined threshold state. Since grinding is performed while pressure adjustment is repeated, the upper surface 2 can be ground and polished more precisely.

  Further, the pressurizing jig 21 is vacuum-adsorbed on the substrate B and, for example, air is introduced into the space AR through the cock 25 and the pressurizing hole 28 and is pressurized. Since the mesa portion 1 can be pressed uniformly, the upper surface 2 can be more uniformly polished.

  Moreover, by removing the external hose 26 after closing the cock 25, it is possible to perform grinding or polishing independently as the polishing apparatus 100, and the convenience can be improved.

(II) Second Embodiment Next, a second embodiment which is another embodiment according to the present invention will be described with reference to FIG. FIG. 4 is a side sectional view showing the configuration of the polishing apparatus according to the second embodiment.

  In the polishing apparatus 100 according to the first embodiment described above, for example, air is introduced to press the position of the mesa unit 1 from the back surface. However, in the polishing apparatus according to the second embodiment described below, a screw is used. Or it is set as the structure which presses the position of the mesa part 1 from a back surface using apparatuses, such as a spring.

  That is, as shown in FIG. 4, the polishing apparatus 200 according to the second embodiment has an upper surface 2 of a trapezoidal (rectangular shape in plan view) formed on the surface of the substrate B as in the first embodiment. Is a polishing apparatus that polishes the substrate with a polishing pad 10 that is fixed to the rotating shaft 11 and rotates. A recess 3 similar to that of the first embodiment is formed on the back side of the surface area including the position of the mesa portion 1 of the substrate B.

  The polishing apparatus 200 includes an outer frame 50 and a pressure jig 51 that is vacuum-adsorbed to the substrate B so as to surround a region including the depression 3 on the back surface of the substrate B. Similar to the pressurizing jig 21 of the first embodiment, the periphery of the pressurizing jig 51 is a circumference for vacuum adsorbing the pressurizing jig 51 to the outside of the region on the back side of the substrate B. A suction groove 52 having a shape and a seal 53 for maintaining the degree of vacuum in the suction groove 52 are provided.

  On the other hand, a recess 57 is formed at a position facing the recess 3 surrounded by the suction groove 52 of the pressurizing jig 51, and the position of the back of the mesa portion 1 in the recess 3 is at the center of the recess 57. A pressing plate 60 to be pressed, an urging portion 61 that urges the pressing plate 60 in the direction of the substrate B, and an adjustment portion 62 that adjusts the urging force by the urging portion 61 are provided. Specifically, the urging portion 61 is, for example, a ball screw or a spring whose pressure can be adjusted. With this structure, by pressing the pressing plate 60 in the direction of the substrate B in a state where the pressing jig 51 is vacuum-adsorbed on the substrate B, the mesa portion 1 of the substrate B is pressed from the back side, and the mesa portion 1 The upper surface 2 is pressed evenly against the polishing pad 10. The adjustment and control of the urging force in this case was obtained by the data acquisition stage work as the second embodiment, basically using the adjusting unit 62, similarly to the polishing apparatus 100 of the first embodiment. This is performed based on data indicating the relationship between the pressure and the polishing amount (see FIG. 2B). At this time, the pressing plate 60 and the urging portion 61 correspond to an example of the “contact pressing means” according to the present invention.

  As described above, according to the polishing apparatus 200 according to the second embodiment, like the inspection apparatus 100 according to the first embodiment, the polishing pad 10 is brought into contact with the polishing pad 10 while being pressed from the back surface side of the substrate B. By polishing the upper surface 2 of the portion 1, even if the substrate B has a thinned region including the position where the mesa portion 1 is formed, the upper surface 2 can be uniformly polished.

  In addition, in the grinding stage, measurement work of the surface shape of the upper surface 2 (see step S13 in FIG. 3) and pressure adjustment operation (step S15 in FIG. 3) are performed until the surface shape of the upper surface 2 reaches a predetermined threshold state. Since the grinding is performed while repeating the surface shape measurement and the pressure adjustment, the upper surface 2 can be ground and polished more precisely.

  In addition to these, according to the polishing apparatus 200 according to the second embodiment, the pressing jig 51 presses the substrate B from the back surface using the pressing plate 60, so that, for example, the pressure during pressing is adjusted flexibly. Thus, the upper surface 2 of the mesa portion 1 can be more uniformly polished.

  In each of the above-described embodiments, the surface other than the position of the mesa portion 1 on the surface of the substrate B is covered with, for example, a film tape or the like during grinding and polishing, so that the mesa portion 1 such as a mark for alignment, for example. In addition to this, it is preferable to prevent the object formed on the surface of the substrate B from being ground or polished.

  As described above, the present invention can be used in the field of polishing apparatuses, and particularly when applied to the field of polishing apparatuses for polishing the surface of an imprint substrate, a particularly remarkable effect can be obtained.

DESCRIPTION OF SYMBOLS 1 Mesa part 2 Upper surface 3 Indentation 10 Polishing pad 11 Rotating shaft 20, 50 Outer frame 21, 51 Pressure jig 22, 52 Adsorption groove 23, 53 Seal 24 Base 25 Cock 26 External hose 27, 57 Recess 28 Pressurization hole 30, 40 Suction Port 31 Groove 41 Dummy Hole 60 Pressing Plate 61 Biasing Unit 62 Adjustment Unit 100, 200 Polishing Device AR Space B Substrate

Claims (8)

A substrate having a convex portion formed on the surface, wherein the region including the position of the surface on which the convex portion is formed is thinned so as to bend the substrate. A polishing method for polishing,
A fixing step of fixing a pressing means to the back surface of the substrate including the thinned region;
While pressing the position of the convex portion from the back side using the fixed pressing means, a polishing step for polishing the top by bringing the polishing means into contact with the top, and
A polishing method comprising: The polishing method according to claim 1,
The polishing step includes
A shape inspection step for inspecting the surface shape of the top to be polished;
An adjustment step for adjusting the pressing force by the pressing means based on the result of the shape inspection;
Including
A polishing method, wherein the top portion is polished while repeating the shape inspection step and the adjustment step until the surface shape is in a preset state. In the polishing method according to claim 1 or 2,
The pressing means is
Sealing means for sealing the thinned region on the back side;
A gas introduction means for introducing gas into the sealed space and pressing the position of the convex portion from the back surface side;
A polishing method comprising: In the polishing method according to claim 1 or 2,
The polishing method according to claim 1, wherein the pressing unit includes a contact pressing unit that is in contact with the thinned region on the back surface and presses the region. A substrate having a convex portion formed on the surface, wherein the region including the position of the surface on which the convex portion is formed is thinned so as to bend the substrate. A polishing apparatus for polishing,
Polishing means;
A pressing unit that is fixed to the back surface of the substrate including the thinned region and presses the position of the convex portion from the back surface side;
Polishing control means for polishing the top by bringing the polishing means into contact with the top while pressing the position of the convex portion from the back side using the fixed pressing means;
A polishing apparatus comprising: The polishing apparatus according to claim 5, wherein
The pressing means is
Sealing means for sealing the thinned region of the back surface;
A gas introduction means for introducing gas into the sealed space and pressing the position of the convex portion from the back surface side;
A polishing apparatus comprising: The polishing apparatus according to claim 6, wherein
The polishing apparatus according to claim 1, wherein the gas introducing unit includes a maintaining unit that maintains a pressing force by the introduced gas after the introduction of the gas. The polishing apparatus according to claim 5, wherein
The polishing apparatus according to claim 1, wherein the pressing unit includes a contact pressing unit that is in contact with the thinned region on the back surface and presses the region.