JP5379564B2 - Imprint apparatus and article manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imprint technique advantageous from the aspect of superposing precision. <P>SOLUTION: This imprint apparatus includes a structure including a mold chuck 2 holding a mold 1, and performs a processing including application of a resin to a base plate 10 and forming the applied resin by the mold. The apparatus is further equipped with a first measuring instrument for measuring the position of a reference part of the structure; a second measuring instrument for measuring the relative position of the mold to the reference part; and a control unit for controlling the relative positional relation between the mold and the base plate based on the measurement results by the first measuring instrument and the measurement results by the second measuring instrument. The second measuring instrument includes a proximity sensor 7 supported by the structure. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to an imprint apparatus and an article manufacturing method.

  The imprint technique is a technique that enables transfer of nanoscale fine patterns, and is being put into practical use as one of lithography techniques for mass production of magnetic storage media and next-generation semiconductor devices. In imprinting, a fine pattern is formed on a substrate such as a silicon wafer or a glass plate using a mold (mold) on which a fine pattern is formed using an apparatus such as an electron beam drawing apparatus as an original plate. The fine pattern is formed by applying an imprint resin on the substrate and curing the resin in a state where the mold pattern is pressed against the substrate through the resin.

  As imprint technologies in practical use at present, there are a thermal cycle method and a photocuring method. In the thermal cycle method, the thermoplastic imprint resin is heated to a temperature equal to or higher than the glass transition temperature, and the mold is pressed against the substrate through the resin in a state where the fluidity of the resin is enhanced. Then, after cooling, the pattern is formed by pulling the mold away from the resin. In the photocuring method, an ultraviolet curable imprint resin is used, and the resin is cured by irradiating the ultraviolet ray with the mold pressed against the substrate through the resin, and then the mold is separated from the cured resin. As a result, a pattern is formed. The thermal cycle method involves an increase in transfer time due to temperature control and a decrease in dimensional accuracy due to a temperature change. However, since the photocuring method does not have such a problem, at present, the photocuring method is nanoscale. This is advantageous in mass production of semiconductor devices.

  Patent Document 1 relates to a technique for manufacturing a semiconductor device on a substrate using an imprint technique. This document describes the entire surface of a wafer by repeating an operation of forming a pattern in a partial region of the wafer. Describes forming a pattern. Thereafter, an etching process or an oxidation process is performed using a pattern formed by imprinting. A semiconductor device having a multilayer structure is manufactured by repeating the above processing. This is the same as the manufacture of a semiconductor device by a photolithography process. As an alignment method for overlaying patterns, Patent Documents 1 and 2 and Non-Patent Document 1 propose a method in which a method used in a semiconductor device manufacturing method by a photolithography process is applied. In particular, Non-Patent Document 1 proposes a global alignment method (AGA) using an off-axis alignment scope. In AGA, prior to the formation of a new pattern, the XY position arrangement state of a pattern group already on the wafer is detected using an off-axis alignment scope. Then, according to this detection result, a new pattern is aligned with each shot area on the wafer.

Japanese Patent No. 4185941 US Pat. No. 7,281,921

Rice, “Nanoimprint Wafer Alignment”, Japan Society for the Promotion of Science, Nanodevice Technology 151st Committee, Nanoimprint Technology Symposium, Japan, Japan Spectroscopic Society, October 7, 2008, p.46 -52

  Imprinting is aimed at practical use for the purpose of forming a pattern equivalent to or finer than an immersion exposure apparatus using an ArF laser. Therefore, the imprint apparatus is required to have an alignment accuracy equal to or higher than that of the current state-of-the-art semiconductor exposure apparatus, that is, several nanometers to tens of nanometers.

  However, in imprinting, when the mold is pulled away from the cured resin, a force is applied in the direction along the pattern surface of the mold, which may cause the position of the mold to deviate from the normal position. If mold misalignment occurs when forming a pattern for each shot area based on AGA information, even if the wafer is positioned on an XY stage with good XY positioning accuracy, the pattern misalignment on the wafer is misaligned. It will occur.

  Patent Document 2 (paragraphs 13 and 14) describes a technique in which a template (mold) is provided with a mirror and its position is monitored from a gantry of the main body. However, with this method, it is necessary to finish the end surface of the template (mold) with surface accuracy that can be measured with a laser interferometer and then coat the reflective film or attach a component having a reflective surface with good surface accuracy to the template. . Further, regarding the reflecting surface, a high degree of orthogonality is required for the two end surfaces among the three orthogonal surfaces including the pattern surface and the two end surfaces. If the orthogonality is poor, the two end face methods can be used even if the rotation angle around the axis parallel to the normal direction of the pattern surface is adjusted (generally called θ alignment) when the template is replaced. Both lines cannot be aligned with the optical axis of the laser interferometer. Therefore, the path of the beam irradiated from one of the laser interferometers and reflected by the end face deviates from the normal path, and the position of the end face cannot be detected.

  In general, it is desired that the surface accuracy of the reflecting surface required for the laser interferometer is ¼ or less of the wavelength of light. That is, a flatness of 0.16 μm or less is required for a laser interferometer using a normal He—Ne laser.

  Although it is technically possible to provide a reflection surface that can be measured by a laser interferometer on the end face of the mold (template), a mold that deteriorates at each imprint has a limited number of uses. Therefore, it seems that there is a big problem from the viewpoint of cost to provide a reflection surface that can be measured by a laser interferometer on the end face of a mass production mold.

  The present invention has been made with the above problem recognition as an opportunity, and for example, an object of the present invention is to provide an imprint technique that is advantageous in terms of overlay accuracy.

  One aspect of the present invention relates to an imprint apparatus that includes a structure including a mold chuck that holds a mold, and performs processing including application of resin to a substrate and molding of the applied resin by the mold, The imprint apparatus includes a first measuring instrument that measures a position of a reference portion of the structure, a second measuring instrument that measures a relative position of the mold with respect to the reference portion, and a measurement by the first measuring instrument. A control unit that controls a relative positional relationship between the mold and the substrate based on a result and a measurement result by the second measuring instrument, and the second measuring instrument is a proximity sensor supported by the structure including.

  According to the present invention, for example, an imprint apparatus that is advantageous in terms of overlay accuracy can be provided.

It is a side view of the imprint apparatus of 1st Embodiment. It is a side view of the imprint apparatus of 2nd Embodiment. It is a front view of the imprint apparatus of 1st and 2nd embodiment. It is a top view of a part of imprint device of a 1st and 2nd embodiment. It is the elements on larger scale of the imprint apparatus of 3rd Embodiment. 5 is a flowchart illustrating an imprint method that can be performed by the imprint apparatus. It is a symbol explanatory table of the laser interferometer measured value of an imprint apparatus. It is a block diagram of a control system of the imprint apparatus.

  Hereinafter, some embodiments of the present invention will be described by way of example with reference to the accompanying drawings. The present invention is useful for forming a nanoscale fine pattern, but is also applicable to forming a pattern having a scale larger than the nanoscale.

[First Embodiment]
The imprint apparatus according to the first embodiment of the present invention will be described with reference to FIGS. 1, 3, and 4. The imprint apparatus INP includes a structure (2, 6) including a mold chuck 2 that holds a mold 1 having a pattern surface P. The imprint apparatus INP is configured to perform processing including application of a resin to the substrate 10 and molding of the applied resin by the mold 1. More specifically, the imprint apparatus INP imprints a pattern on the substrate 10 by applying a resin to the substrate 10 and curing the resin with the pattern surface P pressed against the resin. On the pattern surface P of the mold 1, irregularities constituting the pattern are formed. The mold chuck 2 holds the mold 1 by, for example, vacuum suction. The mold chuck 2 preferably has a structure that prevents the mold 1 from falling off the mold chuck 2. The mold chuck 2 is provided with a sensor support member 6 that supports a proximity sensor 7 (7a to 7m) as a second measuring instrument to be described later. The sensor support member 6 can be considered as a part of the mold chuck 2 or can be considered as a member coupled to the mold chuck 2.

  Interferometer mirrors 3 a and 3 b are attached to the mold chuck 2. The imprint apparatus INP, as a first measuring instrument, is an interferometer 15a (back side in FIG. 1), 15b (front side in FIG. 1) attached to the apparatus reference member 14a, and interference attached to the apparatus reference member 14c. A total of three laser interferometers comprising a total of 15 g are provided. The position of the interferometer mirrors 3a and 3b, that is, the position of the mold chuck 2 is measured by the first measuring instrument. Here, the position in the Y direction of the mold chuck 2 as the reference portion is given by an average value of the position of the interferometer mirror 3a measured by the interferometer 15a and the position of the interferometer mirror 3a measured by the interferometer 15b. It is done. The rotation of the mold chuck 2 around the Z-axis is given by the difference between the position of the interferometer mirror 3a measured by the interferometer 15a and the position of the interferometer mirror 3a measured by the interferometer 15b. The position of the mold chuck 2 in the X direction is given by the position of the interferometer mirror 3b measured by the interferometer 15g. The position of the mold chuck 2 in the Y direction is based on the apparatus reference member 14a. The position of the mold chuck 2 in the X direction is based on the apparatus reference member 14c.

  Each of the three laser interferometers 15a, 15b, and 15g can be configured as a biaxial measurement interferometer, for example. In this case, the distance can be detected by the average value of the two-axis measurement values, and the inclination can be detected by the difference between the two-axis measurement values. Alternatively, each of the three laser interferometers 15a, 15b, and 15g may be configured as a two-axis measurement interferometer by arranging two one-axis interferometers.

  The imprint apparatus INP includes a proximity sensor 7 (7a to 7m) as a second measuring instrument for measuring the relative position of the mold 1 with respect to the mold chuck 2 in the mold chuck 2 as a reference portion. The proximity sensor 7 is preferably capable of measuring a positional deviation with an accuracy of at least nm order. Therefore, the proximity sensor 7 is preferably a capacitance sensor or a spectral interference laser displacement meter. As the spectral interference laser displacement meter, for example, SI series of Keyence Corporation is suitable. Capacitance sensors and spectral interference laser displacement meters generally have a resolution of the nm level, and absolute measurement is possible.

  In the imprint apparatus, when the mold 1 is pulled away from the cured resin (release), the mold 1 held by the mold chuck 2 may move suddenly. A relative length measuring sensor such as a laser interferometer recognizes a position by generating a pulse and increasing or decreasing the count value of the counter according to the pulse. Therefore, when a relative length measurement type sensor is used, the maximum allowable speed is limited by the minimum pulse interval. When the speed of the rapid movement of the mold 1 exceeds the maximum allowable speed, a measurement error occurs.

  On the other hand, when a proximity sensor such as a capacitance sensor or a spectral interference laser displacement meter is used, since absolute length measurement is possible, there is no restriction on the speed of rapid movement of the mold 1. That is, regardless of the speed at which the mold 1 moves, at least the position after the movement can be measured by the proximity sensor. In addition, when a proximity sensor is used, the measurement surface (end surface of the mold 1) does not need to have high surface accuracy, measurement is possible even when the measurement head is inclined with respect to the measurement surface, There is an advantage that a reflective coating is unnecessary.

  On the other hand, when the resolution of the proximity sensor is set to a resolution of nm level, the measurement range is generally limited to several mm or less. Therefore, in this embodiment, based on the position of the mold chuck 2 as the reference portion of the structure (2, 6) including the mold chuck 2 and the relative position of the mold 1 with respect to the reference portion, Detect position. Here, in this embodiment, the position of the mold chuck 2 is measured with reference to the apparatus reference members 14a and 14c. The position of the mold chuck 2 as the reference portion is determined by, for example, the difference between the position of the interferometer mirrors 3a and 3b and the reference position of the mold chuck 2 (for example, the origin of the mold chuck 2) by the interferometers 15a, 15b, and 15g. It can be determined by adding to the measured position. The relative position of the mold 1 with respect to the mold chuck 2 as the reference portion is, for example, a position where the difference between the position of the proximity sensor 7 (7a to 7m) and the reference position of the mold chuck 2 is measured by the proximity sensor 7. It can be determined by adding.

  A configuration example of the control unit CNT of the imprint apparatus INP will be described with reference to FIG. The control unit CNT includes a configuration for controlling the relative positional relationship between the mold 1 and the substrate 10. The control unit CNT determines the position (hereinafter, stage command position) 71 of the substrate stage 24 holding the substrate 10 as a target position. The control unit CNT also detects the position of the mold chuck 2 as the reference portion based on the measurement results by the laser interferometers 15a, 15b, and 15c in accordance with the above-described method, and further the amount of change (hereinafter referred to as the position of the reference portion). Change). The control unit CNT also detects the relative position of the mold 1 with respect to the mold chuck 2 based on the measurement result of the proximity sensor 7 according to the above method, and further calculates the amount of change (hereinafter referred to as the relative position change amount of the mold) 73. calculate.

  For example, when the position of the mold 1 is shifted to the + side, the stage command position 71 should be corrected to the + side. If such correction is not performed, the stage 10 is imprinted on the substrate 10. The pattern shifts to the + side. The control unit CNT includes a correcting unit 79. The correcting unit 79 adds the position change amount 72 of the reference portion and the relative position change amount 73 of the mold to the stage command position 71, thereby setting the stage command position 71. It corrects and outputs the corrected stage command position CT. That is, the control unit CNT determines the stage command position 71, which is the target position of the substrate stage 24 (equivalent to the target position of the substrate), the measurement results by the interferometers (first measuring instruments) 15a, 15b, 15g and the proximity sensor (second sensor). Correction is performed by the correction unit 79 based on the measurement result by the measuring instrument 7. By correcting the stage command position 71 in this way, it is possible to reduce imprint misalignment due to misalignment of the mold 1.

  The corrected stage command position CT is compared with the detection result by the stage position detector (interferometers 15c, 15e) 74 that detects the position of the substrate stage 24, and the difference (ie, deviation) signal thereof is the stabilization compensator 76. And a compensator including a steady-state deviation compensator 77. The compensator generates a drive command DI by performing a compensation operation on the difference signal. The drive command DI is supplied to the stage motor amplifier 78, and the stage motor amplifier 78 drives the stage motor (linear motors 23a, 23b, 23c, etc.) 75, thereby positioning the substrate stage 24 (substrate 10).

  Here, the reason why the surface accuracy and orthogonality of the end face of the mold 1 cannot be improved and the reason why it is difficult to perform the reflective coating will be described, and the usefulness of the use of the proximity sensor will be described.

  The mold 1 can be made of, for example, non-coated synthetic quartz. Since the mold 1 comes into contact with the substrate 10 and the resin when the pattern is formed on the substrate 10, the lifetime of the mold 1 is used as an original plate in an exposure apparatus used in a normal photolithography process due to wear or resin adhesion. It has a very short life compared to a reticle. Therefore, the price of the mold is a cost factor that cannot be ignored when manufacturing a semiconductor device using an imprint apparatus. For this reason, it is difficult to perform a process that increases the cost of the mold with respect to the orthogonality and flatness of the end face of the mold and the reflective coating that are not directly related to the pattern formation.

  In general, the mold 1 can be manufactured by duplicating a very expensive mold called a mother mold. The reason why this mother mold is expensive is that it takes a very long drawing time to draw a pattern in a pattern region with a single stroke of an electron beam having a thin diameter of 1 nm to 40 nm. For example, the area of the imprint pattern region needs to be the same as the area of the shot region in the immersion exposure apparatus when a semiconductor device is manufactured in combination with an immersion exposure apparatus using an ArF laser as a light source. is there. This area is currently the de facto standard of 33 mm × 26 mm. It is said that if the line width of the pattern is less than 20 nm in the future, drawing time of 24 hours or more is required.

  Hereinafter, the description will return to the imprint apparatus INP. The mold chuck 2 may be provided with mold chuck reference plates 4 a and 4 b immediately above the mold side mark formed on the upper surface of the mold 1. Chuck-side marks corresponding to the mold-side marks provided on the mold 1 are formed on the lower surfaces of the mold chuck reference plates 4a and 4b. For example, the chuck side mark can be arranged such that an interval of 2 μm to 300 μm is formed with respect to the mold side mark. By observing the chuck-side mark and the mold-side mark using the alignment microscopes 44a and 44b as optical sensors, it is possible to detect the relative displacement between each other. This detection can be performed by, for example, an image processing method based on bright field observation or moire fringe position measurement. Such alignment microscopes 44a and 44b as optical sensors can be provided in place of or in addition to the proximity sensor 7 (7a to 7m) described above. The alignment microscopes 44a and 44b as optical sensors are also used to measure the relative position of the mold 1 with respect to the mold chuck 2 as a reference portion regardless of the surface accuracy, orthogonality, and reflective coating of the end surface of the mold 1. Useful.

  However, in order to perform position measurement using the alignment microscopes 44a and 44b, a process of forming a mold side mark is required in addition to the process of replicating the pattern from the mother mold. Therefore, when manufacturing a semiconductor device, it may be preferable to form a mold-side mark for position measurement only on the mold 1 used for forming a layer in which overlay accuracy is important. It may be preferable to measure the position with the proximity sensor 7 without providing the mold side mark for position measurement on the mold 1 used for forming an insignificant layer. Also, if both the proximity sensor and the optical sensor are mounted on the imprint apparatus, the cost of the imprint apparatus increases. Therefore, the sensor to be mounted may be determined according to the required specifications.

  In this embodiment, the mold chuck 2 can be supported by a bridge surface plate 13 as a support body via the connecting member 5. The mold chuck 2 may be directly fixed to the bridge surface plate 13. The alignment microscopes 44 a and 44 b can also be supported by the bridge surface plate 13. A half mirror 43 is disposed above the mold chuck 2. The light generated by the light curing light source 41 is reflected by the half mirror 43, passes through the mold 1, and is irradiated onto the resin. The resin is cured by light irradiation. A camera 42 is disposed above the half mirror 43, and the imprint status by the mold 1 can be confirmed via the half mirror 43.

  The bridge surface plate 13 is supported by the support legs 11 installed on the floor via the air spring 12 in order to insulate vibration from the floor. The air spring 12 may have a configuration generally employed in an exposure apparatus as an active image stabilization function. Specifically, the air spring 12 may include an XYZ relative position measurement sensor attached to the upper and lower members thereof, an XYZ direction driving linear motor, and a servo valve that controls the internal air capacity of the air spring.

  In addition, dispensers 8 a and 8 b for applying a photocurable resin onto the substrate 10 are attached to the bridge surface plate 13 via a holder 9. The dispenser 8 can be configured to spray resin droplets linearly on the substrate 10 using, for example, an inkjet head used in an inkjet printer. By spray driving the substrate stage 24 (that is, the substrate 10) while spraying the resin with the dispenser 8, the resin can be applied to the rectangular region on the substrate 10. The original function of the inkjet head is to draw pictures and characters with ink by controlling the ejection of ink from a plurality of fine nozzles arranged in a straight line and the feeding of a recording sheet. Therefore, the area to be ejected does not have to be rectangular, and the resin can be applied to an area having an arbitrary shape such as a circle.

  Since the shape of the wafer as the substrate 10 is generally circular, when the wafer is completely filled with a rectangular shot area, the shot area protrudes from the wafer in the peripheral area, and a rectangular shot area can be secured. Disappear. Such an area is sometimes called a missing shot area. At present, it is general that a plurality of chips can be formed in a shot area of 33 mm × 26 mm. Therefore, in order to efficiently form chips on a wafer, a pattern should be formed also in a missing shot area. .

  At present, when a semiconductor device is manufactured by imprint processing, a film (which may be referred to as a residual film) remains in a concave portion in a concavo-convex pattern formed after imprinting, and thus needs to be etched. The thickness of the film remaining in the recess can be referred to as RLT (Residual Layer Thickness). If the RLT film is not formed in the chipped shot region, the wafer can be deeply wrinkled by etching. In order to prevent this, application of resin to the peripheral region is effective. At this time, if the resin is applied in a square shape, the resin protrudes from the wafer, and if the ultraviolet ray is irradiated in this state, the resin is cured and adhered on the substrate chuck for fixing the wafer. As a result, not only the wafer is bonded to the substrate chuck, but also the wafer to be processed next gets on the deposit, and the surface accuracy of the wafer surface deteriorates and imprinting cannot be performed normally. End up. Therefore, it is preferable to apply the resin to an appropriate region of the wafer by a combination of the dispenser 8 and the substrate stage 24. A resin can be applied to the + Y direction side of the substrate 10 by the dispenser 8b, and a resin can be applied to the −Y direction side of the substrate 10 by the dispenser 8a.

  An alignment microscope (off-axis scope; OAS) 31 for measuring the position of the alignment mark formed on the substrate 10 is disposed on the bridge surface plate 13. As shown in FIG. 3, an interferometer mirror 32 is attached to the side surface of the OAS 31 so that the laser light from the laser interferometer 34a can be reflected. The laser interferometer 34 a is installed so as to be able to measure the distance in the X direction from the device reference member 14 b fixed to the bridge surface plate 13 to the OAS 31.

  Next, the substrate stage 24 that holds the substrate 10 and its driving mechanism will be described. In this embodiment, the base 18 that supports the substrate stage 24 is installed on the floor via an air spring (vibration isolation device) 19 so that vibration and deformation due to the movement of the substrate stage 24 are not transmitted to the bridge surface plate 13. ing. The distance in the Z direction between the bridge surface plate 13 and the substrate stage 24 of the imprint apparatus INP is a sensor (for example, a laser length measuring device, an encoder) 16a fixed to a bracket 30 extending downward from the bridge surface plate 13. It is measured by 16b, 16c, 16d. The members 17a, 17b, 17c, and 17d are measurement target portions corresponding to the sensors 16a, 16b, 16c, and 16d, respectively, and are attached to the base 18. The members 17a, 17b, 17c, and 17d are mirrors if the sensors 16a, 16b, 16c, and 16d are laser length measuring instruments, and are scales if they are encoders.

  In this embodiment, the distance between the bridge surface plate 13 and the base 18 is measured at four locations, but actually, if the measurement is performed at three locations, the distance in the Z direction and the inclination can be detected. it can. By controlling the position and inclination of the substrate stage 24 in the Z direction with respect to the base 18 based on the position and inclination of the base 18 in the Z direction, the position and inclination of the substrate 10 can be corrected. The adjustment amount of the substrate stage 24 can be reduced by adjusting the height of the air spring 12 and the height of the air spring 19 to appropriate values.

  A coarse movement stage 22 is disposed on the base 18. The coarse movement stage 22 is provided with a plurality of air pads 21 and floats on the base 18 with static pressure. When the coarse movement stage 22 is driven in the X and Y directions, if the base 18 is tilted or shaken by a drive reaction force, the pattern formation accuracy is lowered. Therefore, the dummy load is opposite to the drive direction of the coarse movement stage 22. It is preferable to reduce the inclination and reaction force of the base 18 by driving in the direction of. The coarse movement stage 22 is provided with mirrors 25a and 25b, and the apparatus reference member 14a, the laser interferometers 15d, 15f, and 15g (bottom) attached to the apparatus reference members 14a and 14c in the X and Y directions. The distance from 14c is measured. Here, as in the apparatus reference member 14c in the X direction, three two-axis laser interferometers are arranged vertically on the apparatus reference member 14c in the Y direction. The laser interferometer 15g (upper) is the distance in the X direction with the mold chuck 2, the laser interferometer 15g (middle) is the distance in the X direction with the mirror 27 provided on the substrate stage 24, and the laser interferometer 15g (lower) is The distance in the X direction with the mirror 25a provided on the coarse movement stage 22 is measured.

  A substrate stage 24 that is a fine movement stage is disposed on the coarse movement stage 22. The substrate stage (fine movement stage) 24 is supported in a floating state without physically contacting the coarse movement stage 22 by linear motors 23 a, 23 b, and 23 c with a self-weight cancellation function attached to the coarse movement stage 22. The Thereby, it is possible to completely separate the substrate stage 24 from the vibration transmitted from the support leg 19 without being damped. However, the position of the substrate stage 24 cannot be controlled as it is. Therefore, the mirrors 26 and 27 are attached to the side surface of the substrate stage 24, and using these, the X direction, the Y direction, the ωZ (= θ) direction that is the rotation about the Z axis, the ωX direction that is the rotation about the X axis, The position in the ωY direction, which is rotation around the Y axis, is measured. These measurements are made by interferometers 15c and 15e attached to the device reference member 14a in the Y direction and an interferometer 15g (medium) attached to the device reference member 14c in the X direction. With the above configuration, the positional relationship between the mold 1 and the substrate 10 during imprinting is guaranteed. The distance between the coarse movement stage 22 and the substrate stage 24 in the Z direction can be controlled by incorporating an encoder and a laser length measuring device in the linear motors 23a, 23b, and 23c and using the average value of the measurement results obtained by them. .

[Second Embodiment]
An imprint apparatus INP according to a second embodiment of the present invention will be described with reference to FIG. Note that matters not mentioned here are the same as in the first embodiment. The second embodiment is different from the first embodiment in that the reference portion of the structure (2, 6 ′) including the mold chuck 2 is the sensor support member 6 ′. The sensor support member 6 ′ is connected to a bridge surface plate 13 that is a support that supports the mold chuck 2. The sensor support member 6 ′ supports the proximity sensor 7 (7a to 7m). In the first embodiment, the mirrors 3a and 3b provided on the mold chuck 2 are provided on the sensor support member 6 ′ as the sensor support member 6 ′ is changed to the reference portion.

  When the mold 1 is pulled away from the resin on the substrate 10, the mold chuck 2 can vibrate. In the first embodiment, since the measurement target portion by the laser interferometer is the mold chuck 2, a response speed capable of measuring the position of the mold chuck 2 during vibration is required for the laser interferometer. On the other hand, in the second embodiment, the part to be measured by the interferometer is not the mold chuck 2 but the sensor support member 6 ′, so that an interferometer having a lower response speed than the first embodiment can be used.

[Third Embodiment]
An imprint apparatus INP according to a third embodiment of the present invention will be described with reference to FIG. Note that matters not mentioned here are the same as in the first embodiment. In the third embodiment, in the first embodiment, a mold side mark for alignment formed on the upper surface of the mold 1 is formed on the lower surface of the mold 1.

  As mentioned in the description of the first embodiment, disposing a pattern other than the pattern of the semiconductor device on the upper surface of the mold 1 (the surface on the opposite side of the pattern surface) causes an increase in the cost of the mold 1. I want to avoid it in system design. In addition, since the alignment accuracy between the alignment pattern and the pattern of the semiconductor device is strictly required, a high technical skill is required to form the alignment pattern on the upper surface of the mold 1. The

  Therefore, if a mark is formed in advance on a mother mold on which a pattern is drawn by an electron beam drawing apparatus and the mold 1 is created, the cost of the mold 1 can be reduced if the mark can be formed in the same process as the pattern of the semiconductor device. Is possible. The optical system 46 b and the mold chuck reference plate 4 b can be mounted on the mold chuck 2. In this embodiment, a chuck side mark 45b is formed on the lower surface of the glass material constituting the mold chuck reference plate 4b. The optical system 46b projects the optical conjugate image of the mold side mark 47b formed on the lower surface of the mold 1 onto the chuck side mark 45b formed on the mold chuck reference plate 4b. The alignment microscope 44b simultaneously observes the optical conjugate image of the mold side mark 47b and the chuck side mark 45b, and reads the deviation amount to detect the positional deviation between the mold chuck 2 and the mold 1.

[Imprint method]
Hereinafter, an imprint method that can be performed by the imprint apparatus INP according to the first to third embodiments will be exemplarily described with reference to FIGS. 6 and 7. FIG. 7 describes the symbols described in the flowchart shown in FIG.

  In step 51, the substrate (wafer) 10 is carried into the imprint apparatus INP and fixed on the substrate chuck of the substrate stage 24. Each time a predetermined number of substrates 10 are processed, an error in the positional relationship between the reference position of the OAS 31 and the mold 1 can be measured using the stage reference mark 33 provided on the substrate stage 24. A transport system unit that carries the substrate 10 into and out of the imprint apparatus INP will be described as being arranged in the left direction in FIG. In step 51, when the substrate 10 is carried in and out, the substrate stage 24 moves in the -Y direction and moves closer to the transport system unit. Thereby, the time for the transport system unit to transport the substrate 10 can be shortened.

  Since the mirror 27 attached to the substrate stage 24 in step 51 also moves to the -Y side, in step 52, the position of the substrate stage 24 can be measured by the laser interferometer 34b attached to the apparatus reference member 14b. In a normal laser interferometer, measurement cannot be performed if a mirror, which is a measurement object, deviates from the optical axis of the laser beam. However, when the OAS 31 is used to measure the mark on the substrate 10 so that the mirror does not come off from the beams of the two laser interferometers with the full stroke in the Y direction of the substrate stage 24, the mirror becomes very long. . This greatly reduces the rigidity of the mirror itself and narrows the control band. Further, when the substrate stage on which the long mirror is mounted moves in the XY direction, the occupied area of the imprint apparatus INP becomes large.

  In this embodiment, the laser interferometers 34a and 34b are reset when the substrate stage 24 moves in the -Y direction and measurement is possible with the laser interferometer 34b. The laser interferometer is generally a relative length measuring method, and when reset, it is necessary to give the current distance from the upper control device.

  Therefore, first, the measurement values X and ωY of the substrate stage 24 at the laser interferometer 15g (medium) attached to the apparatus reference member 14c in the X direction are set as the current measurement values of the laser interferometer 34b.

  In step 53, the position control method of the substrate stage 24 in the X direction and the ωY direction is changed. Until this timing, the positions of the substrate stage 24 in the X direction and the ωY direction are controlled by the measured values Xtwt and ωYtwt by the laser interferometer 15g attached to the apparatus reference member 14c in the X direction.

  Up to this point, the position of the substrate stage 24 is controlled based on the relative position with respect to the mold chuck 2 or the sensor support member 6 ′ which is the reference portion in all directions except for the Z direction out of 6 degrees of freedom generally referred to. Yes.

  From this control state, the X direction and the ωY direction are switched to the control based on the measurement result by the OAS 31. In the θ direction, the control based on θwt is switched to the control based on θw. If this switching is not performed, if the position of the reference portion is displaced for some reason during AGA measurement in the next step 54, an error is mixed into the AGA measurement value.

  In step 55, during the AGA measurement, a switching error between the measured values of Xow and Xtw is obtained by an averaging process. In step 56, the substrate stage 24 is driven to a region below the mold 1. In steps 57 to 59, the reference for controlling the stage is switched. FIG. 6 shows an example in which the stage command position is corrected before imprinting. However, as described with reference to FIG. 8, the stage command position is corrected in real time based on the deviation of the mold 1. Also good.

  In the configuration illustrated in FIG. 4, three proximity sensors 7 are arranged for each of the four sides of the mold 1, so that it is possible to detect not only misalignment accompanying mold release but also shape deformation. It has become. Therefore, the magnification component and the deformation component are separated from the measurement results of the twelve proximity sensors 7 in total, and based on this, the XY shift amount and the rotation amount at the center of the mold 1 are separated, and the position of the substrate stage 24 is corrected. The

  The number of proximity sensors 7 is not limited to a specific number. As the number of proximity sensors increases, the correction value can be measured with high accuracy.

  In step 60, pattern formation by imprinting is performed on the entire surface of the substrate 10. In step 61, it is determined whether or not the imprint of the final shot area has been completed. If it has not been completed, the next shot area is imprinted in step 60. move on. In step 62, the substrate 10 is unloaded, and in step 53, the presence / absence of the substrate 10 to be processed is confirmed. If there is a substrate 10 to be processed, the process returns to step 51. The job ends.

  The rotation component is measured for the reference portion (for example, the mold chuck 2, the sensor support member 6 ′), the mold 1, the substrate stage 24, etc., but the measurement result of the rotation component is used for correcting the Abbe amount. Can be done.

[Product Manufacturing Method]
The method of manufacturing devices (semiconductor integrated circuit elements, liquid crystal display elements, etc.) as articles is to transfer (form) a pattern onto a substrate (wafer, glass plate, film substrate, etc.) using the above-described imprint apparatus (imprinting apparatus). Step). Further, the manufacturing method may include a step of etching the substrate to which the pattern has been transferred. When manufacturing other articles such as patterned media (recording media) and optical elements, the manufacturing method includes other processing steps for processing the substrate to which the pattern has been transferred, instead of the etching step. May be included.

  The device manufacturing method of this embodiment is more advantageous than the conventional one in at least one of device performance, quality, productivity, and production cost.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to these embodiment, A various deformation | transformation and change are possible within the range of the summary.

Claims (8)

An imprint apparatus comprising a structure including a mold chuck for holding a mold, and performing processing including application of a resin to a substrate and molding of the applied resin by the mold,
A first measuring instrument for measuring a position of a reference portion of the structure;
A second measuring instrument for measuring a relative position of the mold with respect to the reference portion;
A control unit that controls a relative positional relationship between the mold and the substrate based on a measurement result by the first measuring instrument and a measurement result by the second measuring instrument;
The second measuring instrument includes a proximity sensor supported by the structure.
An imprint apparatus characterized by that. The control unit corrects a target position of the substrate based on a measurement result by the first measuring instrument and a measurement result by the second measuring instrument, and positions the substrate according to the corrected target position, whereby the mold Controlling the relative positional relationship between the substrate and the substrate,
The imprint apparatus according to claim 1. The first measuring instrument includes a laser interferometer,
The imprint apparatus according to claim 1, wherein the apparatus is an imprint apparatus. The reference portion is the mold chuck;
The imprint apparatus according to claim 1, wherein the imprint apparatus according to claim 1. The structure includes a support that supports the mold chuck, and a sensor support member that is coupled to the support and supports the second measuring instrument,
The reference portion is the sensor support member;
The imprint apparatus according to claim 1, wherein the apparatus is an imprint apparatus. The second measuring instrument further includes an optical sensor supported by the structure so as to measure a position of a mark formed on the mold.
The imprint apparatus according to any one of claims 1 to 5, wherein: An imprint apparatus comprising a structure including a mold chuck for holding a mold, and performing processing including application of a resin to a substrate and molding of the applied resin by the mold,
A first measuring instrument for measuring a position of a reference portion of the structure;
A second instrument to measure the relative position of the mold with respect to the reference portion;
A control unit for controlling a relative positional relationship between the mold and the substrate based on a measurement result by the first measuring instrument and a measurement result by the second measuring instrument;
The second measuring instrument includes an optical sensor that measures a positional deviation between a mark provided on the mold chuck and a mark provided on the mold.
An imprint apparatus characterized by that. Forming a resin pattern on a substrate using the imprint apparatus according to claim 1;
Processing the substrate on which the pattern is formed in the step;
A method for producing an article comprising:

Images