JP2018018988A - Alignment device, alignment method, position detection device, lithography device, and method for manufacturing object - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an alignment device capable of achieving both the accuracy improvement and the responsiveness improvement of alignment control.SOLUTION: An alignment device includes a first measurement part and a second measurement part for measuring the position of a mark of an object, the first measurement part and the second measurement part respectively include a light-receiving element array and an optical system, the second measurement part is configured to have a measurement time being a time from the reception of light by the light-receiving element array until the conversion of the light into a signal to be shorter than in the first measurement part, first position information of the object is acquired from the position of the mark measured by the first measurement part, second position information of the object is acquired from the position of the mark measured by the second measurement part, and the alignment of the object is performed by using an element other than a differentiation element of a deviation between the first position information and an alignment target value, and a differentiation element of a deviation between the second position information and the alignment target value as inputs.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an alignment apparatus, an alignment method, a position detection apparatus, a lithography apparatus, and an article manufacturing method.

  The demand for miniaturization of semiconductor devices, MEMS, and the like has progressed, and there is a fine processing technology for forming an imprint material on a substrate such as a wafer, a glass plate, or a film-like substrate with a mold and forming a pattern of the imprint material on the substrate. It attracts attention. This technique is also called an imprint technique, and can form a fine structure on the order of several nanometers on a substrate.

  Japanese Patent Application Laid-Open No. 2005-228561 discloses an apparatus that applies step-and-flash imprint lithography, which is advantageous in terms of manufacturing devices and the like, in an imprint apparatus using an imprint technique.

  In the imprint apparatus, first, an imprint material is applied to a shot area which is an imprint area on a substrate. Next, while aligning the pattern area of the mold and the shot area, the pattern area is brought into contact with (imprinted with) the imprint material, and the imprint material is filled into the pattern area. And the pattern of the said imprint material is formed on a board | substrate by irradiating an ultraviolet-ray and hardening the said imprint material, and then separating.

  Further, in order to apply nanometer order fine pattern formation in an imprint apparatus to a mass production process, it is required to improve the alignment accuracy. For this purpose, a pattern region of a mold and a shot region on a substrate are required. The alignment is important.

  In the imprint apparatus, a die-by-die alignment method can be used for alignment between a pattern region of a mold and a shot region on a substrate. In this method, for each shot area on the substrate, the alignment mark provided on the mold and the alignment mark provided on the substrate are optically detected, and the positional deviation between the pattern area of the mold and the shot area on the substrate is detected. And correct the shape difference.

  Patent Document 2 describes a position detection device that detects a mark for relative alignment between a mold and a substrate. In Patent Document 2, a position detection device guides light from a light source by an illumination optical system, and detects moire fringes generated by diffracted light from a mold side mark and a substrate side mark by a detection optical system. Then, the moire fringes are converted into an electrical signal and output, and based on the output result, the drive mechanism on which the substrate is arranged is driven to perform alignment control between the mold and the substrate. If high responsiveness is realized in this alignment control, the time required for the alignment can be shortened. In addition, with a demand for improvement in alignment accuracy, alignment control with higher accuracy is required. From these viewpoints, alignment control is desired to have higher responsiveness and higher accuracy.

Japanese Patent No. 4185941 JP 2013-30757 A

  Conventional alignment control obtains relative position information of a wafer and a mold from measurement results of marks formed on the wafer and the mold, respectively. A deviation between the relative position information and a target value for alignment of the wafer and the mold is calculated, and the wafer stage on which the wafer is mounted is controlled via the first compensator and the second compensator. Here, the first compensator obtains an input signal (input) by an element other than the differential element of the deviation, that is, one or both of the proportional element of the deviation and the integral element of the deviation. The second compensator obtains an input signal based on the differential element of the relative position information.

Here, the equation (1) for obtaining the input signal In has a proportional gain K _p , a proportional term obtained from the deviation proportional value P, an integral gain K _i , an integral term obtained from the deviation integrated value I, When the differential gain is K _d and the differential term obtained from the differential value of the deviation is D,
In = _Kp * P + _Ki * I + _Kd * D (1)
It is represented by

The proportional element of the deviation is a term composed of a proportional gain _Kp and a proportional term P in Equation (1). Since the input signal proportional to the magnitude of the deviation can be obtained by the proportional element, the deviation can be gradually brought close to zero. Further, the integral element of the deviation is a term composed of the integral gain K _i and the integral term I in the equation (1). Since an input signal corresponding to the accumulated value of the deviation can be obtained by the integral element, the remaining deviation that cannot be controlled only by the proportional term can be made closer to zero. The differential element of the deviation is a term composed of the differential gain _Kd and the differential term D in the equation (1). Since the input signal can be adjusted according to the change of the deviation in unit time by the differential element, the control dead time can be shortened when the deviation changes suddenly due to disturbance or the like, and the residual can be reduced to 0 in a short time. You can get closer to. Here, the dead time is the time that elapses after the input signal is given to the controlled object until the output signal corresponding to the input signal appears.

  However, the responsiveness and accuracy of alignment control depend on the processing time of the measurement unit and the amount of data to be acquired. If the amount of data acquired by the measuring unit is increased for the purpose of improving the accuracy of alignment control, the time required for data processing increases and the alignment control response decreases. Further, if the data processing time is reduced by reducing the amount of data acquired by the measurement unit for the purpose of improving the responsiveness of the alignment control, the accuracy of the alignment control is lowered. For this reason, it becomes difficult to achieve both the precision and responsiveness of alignment control.

  Therefore, an object of the present invention is to provide an alignment apparatus, an alignment method, a position detection apparatus, a lithographic apparatus, and an article manufacturing method capable of achieving both alignment control accuracy and responsiveness.

  An alignment apparatus according to one aspect of the present invention that solves the above-described problem is an alignment apparatus that aligns an object, a position detection unit that detects a position of a mark of the object, and a movement that moves the object A first measurement unit and a second measurement unit that receive light from the mark and measure the position of the mark, and the first measurement unit And the second measuring unit each include a light receiving element array for receiving the light and an optical system that forms an image of the light on the light receiving element array. The second measurement unit has a shorter measurement time, which is a time from when the light is received by the light receiving element array to when the light is converted into a signal, or the second measurement unit than the first measurement unit. The light is received by the light receiving element array and the light is received. The measurement range, which is a range to be converted into a signal, is narrow, or the time from when the second measurement unit receives the light by the light receiving element array to the time when the light is converted into a signal than the first measurement unit And the control unit is configured to narrow the measurement range, which is a range in which the light is received by the light receiving element array and converted into a signal. The first position information of the object is acquired from the position of the mark measured by the unit, the second position information of the object is acquired from the position of the mark measured by the second measurement unit, and the first position information and The object is aligned using the elements other than the differential element of deviation from the alignment target value and the differential element of deviation between the second position information and the alignment target value as inputs. Control the moving part.

  According to the present invention, it is possible to provide an alignment apparatus, an alignment method, a position detection apparatus, a lithographic apparatus, and an article manufacturing method capable of achieving both alignment control accuracy and responsiveness.

It is a figure which shows an imprint apparatus. It is a figure which shows the structure of an alignment scope. It is a figure which shows the block diagram in the alignment control which concerns on Example 1. FIG. FIG. 10 is a block diagram illustrating alignment control according to the second embodiment. It is a figure which shows the structure of an alignment scope. It is a figure which shows the 1st integration amount calculated | required by the signal processing of a moire fringe. It is a figure which shows the 2nd integration amount calculated | required by the signal processing of a moire fringe. It is a figure for demonstrating the manufacturing method of articles | goods.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In the following embodiments, an example in which an imprint apparatus is used as a lithography apparatus will be described. In each figure, the same members are denoted by the same reference numerals, and redundant description is omitted.

  The imprint apparatus will be described. FIG. 1 is a diagram illustrating an imprint apparatus. The imprint apparatus 1 brings the imprint material 15 supplied on the wafer 9 into contact with the mold 7 and applies energy for curing to the imprint material 15, whereby the cured product to which the uneven pattern of the mold 7 is transferred is transferred. An apparatus for forming a pattern.

  Here, a curable composition (also referred to as an uncured resin) that cures when energy for curing is applied is used for the imprint material 15. As the energy for curing, electromagnetic waves, heat, or the like is used. The electromagnetic wave may be, for example, light such as infrared rays, visible rays, and ultraviolet rays, the wavelength of which is selected from a range of 150 nm to 1 mm.

  A curable composition is a composition which hardens | cures by irradiation of light or by heating. Among these, the photocurable composition cured by light contains at least a polymerizable compound and a photopolymerization initiator, and may contain a non-polymerizable compound or a solvent as necessary. The non-polymerizable compound is at least one selected from the group consisting of a sensitizer, a hydrogen donor, an internal release agent, a surfactant, an antioxidant, and a polymer component.

  The imprint material 15 is applied in a film shape on the wafer 9 by a spin coater or a slit coater. Alternatively, it may be applied onto the wafer 9 in the form of droplets or an island or film formed by connecting a plurality of droplets by a liquid ejecting head. The viscosity of the imprint material 15 (viscosity at 25 ° C.) is, for example, 1 mPa · s or more and 100 mPa · s or less.

  Although the imprint apparatus 1 is described as an imprint apparatus that employs a photocuring method, the imprint apparatus 1 may be an imprint apparatus that employs a method of curing the imprint material 15 with other energy such as heat.

  The imprint apparatus 1 includes a light irradiation unit 2, a mold holding mechanism 3, a stage 4, a coating unit 5, a wafer heating mechanism 24, a control unit 6, and an alignment scope 22 (position detection unit).

  The light irradiation unit 2 irradiates the mold 7 with light 8 during the imprint process. Although not shown, the light irradiation unit 2 is a light source and an optical element for adjusting the light 8 emitted from the light source to a light state suitable for imprinting (light intensity distribution, illumination region, etc.). (Lens, mirror, light shielding plate, etc.) and light quantity control means.

  The mold 7 (first object) includes a pattern portion 10 formed in a three-dimensional shape on the surface with respect to the wafer 9 (second object). The pattern part 10 is, for example, a concavo-convex pattern to be transferred such as a circuit pattern. The material of the mold 7 is a material that can transmit light 8 such as quartz. Further, a light transmitting member 14 having a space 13 enclosed by a part of the opening region 12 and the mold 7 as a sealed space is installed in an opening region 12 in the mold holding mechanism 3 to be described later, and a pressure adjusting device (not shown). ) May be used to control the pressure in the space 13. For example, when the mold 7 and the imprint material 15 on the wafer 9 are pressed, the pressure in the space 13 is set higher than the outside by the pressure adjusting device. As a result, the pattern portion 10 bends in a convex shape toward the wafer 9 and comes into contact with the imprint material 15 from the center portion of the pattern portion 10. Therefore, it is possible to prevent the gas (air) from being confined between the pattern portion 10 and the imprint material 15 and fill the uneven portion of the pattern portion 10 with the imprint material 15 to every corner.

  The mold holding mechanism 3 has a mold chuck 16 that attracts and holds the mold 7 by a vacuum suction force or an electrostatic force. The mold holding mechanism 3 includes a mold driving mechanism 17 that holds the mold chuck 16 and moves the mold chuck 16 and the mold 7 held by the mold chuck 16. The mold chuck 16 and the mold driving mechanism 17 have an opening region 12 at the center (inside) so that the light 8 emitted from the light source of the light irradiation unit 2 is irradiated toward the wafer 9. Further, the mold holding mechanism 3 has a magnification correction mechanism 18 that corrects the shape of the pattern portion 10 by applying an external force from the side surface of the mold 7 and displacing it on the mold chuck 16 holding side of the mold 7. The magnification correction mechanism 18 deforms the shape of the mold 7 to match the shape of the pattern portion 10 formed on the mold 7 with the shape of the substrate-side pattern previously formed on the wafer 9. it can. The mold driving mechanism 17 moves the mold 7 in the Z-axis direction so as to selectively press or separate the mold 7 and the imprint material 15 on the wafer 9. As an actuator that can be employed in the mold drive mechanism 17, for example, there is a linear motor or an air cylinder.

  The wafer 9 is made of glass, ceramics, metal, semiconductor, resin, or the like, and a member made of a material different from that of the wafer 9 may be formed on the surface as necessary. Specifically, the wafer 9 is a silicon wafer, a compound semiconductor wafer, quartz glass, or the like.

  The stage 4 holds the wafer 9 and performs alignment between the mold 7 and the wafer 9 when the mold 7 and the imprint material 15 on the wafer 9 are pressed. The stage 4 includes a wafer chuck 19 that holds the wafer 9 by an attractive force, and a stage drive mechanism 20 (moving unit) that holds the wafer chuck 19 by mechanical means and is movable in the XY plane. Further, the wafer chuck 19 includes a plurality of suction portions (not shown) that can hold the back surface of the wafer 9 by suction in a plurality of regions. The plurality of suction units are respectively connected to different pressure adjusting devices, and the pressure values (suction force) can be changed independently at each suction unit. The wafer chuck 19 has a reference mark 21 that is used when aligning the mold 7 on the surface thereof. The stage drive mechanism 20 can employ, for example, a linear motor as an actuator. The stage drive mechanism 20 may be composed of a plurality of drive systems such as a coarse motion drive system and a fine motion drive system in each direction of the X axis and the Y axis. The stage drive mechanism 20 is driven to move the wafer 9 so that the mold 7 and the wafer 9 are aligned. The mold driving mechanism 17 (moving unit) is configured to be driven in each of the X-axis and Y-axis directions, and the mold driving mechanism 17 is driven to move the mold 7 so that the mold 7 and the wafer are moved. Alignment with 9 may be performed. Further, the positioning of the mold 7 and the wafer 9 may be performed by driving the stage driving mechanism 20 and the mold driving mechanism 17 to move the wafer 9 and the mold 7.

  The application unit 5 applies the imprint material 15 onto the wafer 9. The amount of the imprint material 15 discharged from the discharge nozzle of the application unit 5 is also appropriately determined depending on the desired thickness of the imprint material 15 formed on the wafer 9 and the density of the pattern to be formed.

  The wafer heating mechanism 24 heats the wafer 9 in order to correct the shape of the wafer 9 placed on the stage 4, specifically, the shape of the shot area existing on the wafer 9. As the wafer heating mechanism 24, for example, as shown in FIG. (Shown) can be adopted. The light emitted from the heating light source is light having a wavelength in a specific wavelength band such as infrared rays that is absorbed by the wafer 9 and is not exposed (cured) by the photocurable imprint material. The wafer heating mechanism 24 also has a plurality of optical elements (lenses, mirrors, light shields) for adjusting the light emitted from the heating light source to a light state suitable for heating (light intensity distribution, illumination region, etc.). Plate and the like) and light amount control means (not shown).

  The control unit 6 can control operation and adjustment of each component of the imprint apparatus 1. The control unit 6 is configured by a computer, for example, is connected to each component of the imprint apparatus 1 via a line, and can control each component according to a program. Moreover, the control part 6 may be comprised with one computer, and may be comprised with several computer.

  The alignment scope 22 is disposed in the opening region 12, and the X axis and Y axis directions of the alignment mark (second mark) formed on the wafer 9 and the alignment mark (first mark) formed on the mold 7. Measure the displacement to The alignment scope 22 is mounted on the positioning mechanism 23 (driving unit), and the alignment mark 23 can be driven to place the alignment mark within the measurement range of the alignment scope 22. As an actuator of the positioning mechanism 23, for example, a linear motor can be adopted. Further, light is incident on the alignment scope 22 from the alignment light source 11, and the alignment mark is illuminated through the alignment scope 22. The alignment scope 22 includes an optical element (lens, mirror, light-shielding plate, etc.) for adjusting the light incident from the alignment light source 11 to a light state suitable for measurement (light intensity distribution, illumination region, etc.), light quantity, And an optical system (not shown) including wavelength control means.

  Next, alignment control according to the first embodiment will be described with reference to FIGS. First, the configuration of the alignment scope 22a will be described. FIG. 2 is a diagram showing a configuration of the alignment scope 22a. The alignment scope 22a constitutes a first measurement unit 227a and a second measurement unit 227b. Each of the first measurement unit 227a and the second measurement unit 227b includes a light receiving element array for receiving light and an optical system for imaging light on the light receiving element array.

  The light emitted from the alignment light source 11 is guided to the separation prism 225 via the fiber 221 and the illumination unit lens 222. Further, the light is reflected by the mirror 223 in the separation prism 225 and guided to the alignment mark formed on the mold 7 and the alignment mark formed on the wafer 9 via the objective lens 224. Light from the alignment mark on the wafer 9 and the alignment mark on the mold 7 is separated by the second separation prism 225 b (separation unit) via the objective lens 224. Then, one of the separated lights is received by the light receiving element arrays of the first measuring unit 227a and the second measuring unit 227b through the first relay lens 226a, and the other through the second relay lens 226b, respectively. An image of the alignment mark is formed. The respective light receiving element arrays of the first measurement unit 227a and the second measurement unit 227b convert light from the mark into an electrical signal by photoelectric conversion. And the control part 6 acquires the relative position information of the mold 7 and the wafer 9 from the electric signal photoelectrically converted.

  Moreover, in Example 1, in order to make the measurement time of the 2nd measurement part 227b shorter than the measurement time of the 1st measurement part 227a, light reception of the 1st measurement part 227a is used as a light receiving element array of the 2nd measurement part 227b. A light receiving element array faster than the element array is used. For example, when a CCD or a CMOS sensor is employed for the light receiving element array of the first measuring unit 227a, an APD (avalanche photodiode) may be employed as the light receiving element for the light receiving element array of the second measuring unit 227b. In general, since APD has high light receiving sensitivity, the time from receiving light to converting it into an electric signal is short, and light can be converted into a signal faster than a CCD or CMOS sensor. However, when a light receiving element such as an APD is employed, the resolution may not be sufficiently high. Therefore, it is used together with the first measurement unit 227a using the light receiving element array capable of sufficiently increasing the resolution. Thereby, measurement time can be shortened by the 2nd measurement part 227b, with the measurement precision maintained by the 1st measurement part 227a. Here, the measurement time is a time from when the light from the alignment mark is received by the light receiving element array of the first measurement unit 227a or the second measurement unit 227b until the light is converted into an electric signal by photoelectric conversion. be able to. The measurement range may be a range in which light from the alignment mark is received by the light receiving element array of the first measurement unit 227a or the second measurement unit 227b and the light is converted into an electric signal by photoelectric conversion.

  Here, the alignment mark of the wafer 9 and the alignment mark of the mold 7 may include a lattice pattern mark. The marks of the lattice pattern are arranged on the mold 7 and the wafer 9, respectively. The mark on the mold 7 side includes a lattice pattern having a lattice pitch in the measurement direction, and the mark on the wafer 9 side is a checkerboard-like lattice having lattice pitches in the measurement direction and the direction orthogonal to the measurement direction (non-measurement direction). Includes patterns. The grating pitch in the measurement direction between the mark on the mold 7 side and the mark on the wafer 9 side is slightly different from each other. When such grating patterns having different grating pitches are overlapped, interference fringes (moire fringes) having a period reflecting the difference in the grating pitch between the grating patterns appear due to interference between the diffracted lights from the two grating patterns. At this time, since the phase of the moire fringe changes depending on the positional relationship between the lattice patterns, the relative position between the marks can be detected by observing the phase of the moire fringe.

  Alternatively, the alignment mark of the wafer 9 and the alignment mark of the mold 7 may include marks of other specific shapes such as a circle, a cross, an L shape, a bar, a square shape, a square shape, and a mountain shape. In this case, the relative position between marks can be detected by observing the distance between specific positions such as the center of the alignment mark.

  In order to observe the image of the alignment mark by the first measurement unit 227a and the second measurement unit 227b, the first measurement unit 227a and the second measurement unit 227b are provided in the same alignment scope 22a.

  FIG. 3 is a block diagram of the alignment control according to the first embodiment. The first measurement unit 227a measures the alignment mark in the measurement range 31, and detects relative position information (first relative position information) between the mold 7 and the wafer 9. The relative position information is input to a first compensator, and an input signal is obtained based on a deviation between the first relative position information and a target value for alignment of the wafer 9 and the mold 7. Here, the first compensator obtains an input signal (input) by an element other than the differential element of the deviation, that is, one or both of the proportional element of the deviation and the integral element of the deviation. The 1st measurement part 227a performs the measurement for calculating | requiring the input signal by elements other than the differential element of the said deviation for which high responsiveness is not requested | required. The second measurement unit 227b measures the alignment mark in the measurement range 32, and acquires relative position information (second relative position information) between the mold 7 and the wafer 9. The relative position information is input to a second compensator, and the second compensator obtains an input signal by a differential element of a deviation between the second relative position information and a target value for alignment of the wafer 9 and the mold 7. Control using such an input signal is feedback control that makes the deviation between the relative position and the target value zero. In addition to PID control using proportional elements, integral elements, and differential elements, PD control using proportional elements and differential elements is also available.

  The measurement range 31 of the first measurement unit 227a and the measurement range 32 of the second measurement unit 227b are the same, but the light receiving element array of the second measurement unit 227b is faster than the light receiving element array of the first measurement unit 227a. Is adopted. In addition, the control cycle of the alignment control is set according to the time from the measurement by the second measurement unit 227b until the second compensator obtains the differential element. Thereby, the differential element is obtained from the latest measurement result of the second measurement unit 227b. On the other hand, when the proportional element and the integral element cannot be obtained from the latest measurement result of the first measurement unit 227a, they are obtained from the measurement results measured in the past.

  Since the relative position between the mold 7 and the wafer 9 can be detected at a short interval by the second measuring unit 227b, the value of the differential element obtained from the relative position is updated at a short interval. For example, when the relative position changes abruptly, the value of the differential element is greatly updated at short intervals. Therefore, the response of control is improved by reflecting the value in the input signal in a short time. On the other hand, since it takes a certain time to reflect the value of the proportional element and the value of the integral element in the input signal and to control the deviation to be close to 0, the control is performed even if it is reflected in the input signal in a short time. There is little improvement in responsiveness. Therefore, the light receiving element array of the second measuring unit 227b employs a light receiving element array that is faster than the light receiving element array of the first measuring unit 227a.

  As described above, the second measurement unit 227b can measure the relative position between the mold 7 and the wafer 9 in a shorter measurement time than the first measurement unit 227a. Then, the differential element obtained from the differential value of the deviation is calculated, and the differential element is reflected in the input signal of the alignment control of the stage 4. Thereby, even when the relative position between the mold 7 and the wafer 9 to be controlled changes suddenly, the dead time can be shortened, and the alignment control between the mold 7 and the wafer 9 is performed in a short time. It becomes possible.

  In the present embodiment, the embodiment in which the relative position between the mold 7 and the wafer 9 is aligned has been described. However, the alignment of the mold 7, the wafer 9, or other object on which the alignment mark is formed is aligned (positioned). ) Applicable to form. For example, the present invention can be applied to an embodiment in which the alignment mark formed on the wafer 9 (object) is measured to obtain the current position of the wafer 9, and the wafer 9 is aligned so that the position of the wafer 9 matches the target position. It is.

  Therefore, the responsiveness of the alignment control is improved by reflecting the differential element of the deviation in the input signal In in a short time.

  As described above, the imprint apparatus according to the first embodiment can achieve both the accuracy of alignment control and the responsiveness.

  An imprint apparatus according to the second embodiment will be described. The alignment scope in the second embodiment is the same as the alignment scope 22a in FIG. In the block diagram of the alignment control in FIG. 4, the same components as those in FIG. In the second embodiment, in the alignment scope 22a, the measurement range 42 of the second measurement unit 227b is narrower than the measurement range 41 of the first measurement unit 227a within a range in which the image of the alignment mark can be measured. For example, a line sensor in which light receiving elements are arranged on a line can be employed. When a line sensor is employed, light is received by a light receiving element array with a narrow measurement range, so that light can be converted into a signal at high speed. As the light receiving element of the line sensor, for example, a light receiving element such as a CCD or a CMOS can be adopted, but it is desirable to adopt the APD light receiving element described in the first embodiment for further speeding up. Further, by adopting an area sensor instead of a line sensor, a diaphragm (not shown) may be arranged on the optical path from the second separation prism 225b to the second measurement unit 227b to narrow the light receiving element array. good. Further, the range in which the light received by the light receiving element array is converted into a signal may be narrowed. However, when the measurement range 42 of the second measurement unit 227b is narrowed, the resolution may not be sufficiently increased. Therefore, it is used together with the first measurement unit 227a using the light receiving element array capable of sufficiently increasing the resolution. Thereby, measurement time can be shortened by the 2nd measurement part 227b, with the measurement precision maintained with the 1st measurement part 227a.

  Therefore, highly responsive alignment control is possible while maintaining measurement accuracy. Then, a differential element is calculated by differentiating the deviation between the relative position information and the target value for alignment of the wafer 9 and the mold 7, and the differential element is reflected in the input signal for the alignment control of the stage 4. Thereby, alignment control between the mold 7 and the wafer 9 can be performed with a short control time with a short dead time. Therefore, it is possible to shorten the data processing time in the second measurement unit 227b while maintaining the measurement accuracy.

  FIG. 4 is a block diagram illustrating the alignment control according to the second embodiment. The measurement range 41 of the first measurement unit 227a is set to a range including the entire alignment mark, and the first measurement unit 227a measures the entire image of the alignment mark. In addition, the measurement range 42 of the second measurement unit 227b is set within a range in which the image of the alignment mark can be measured, and is limited to a part of the alignment mark, and the second measurement unit 227b Measure the image. When the measurement range 42 of the second measurement unit 227b is limited, there is a possibility that the image of the alignment mark is out of the measurement range 42 of the second measurement unit 227b. In this case, based on the measurement result of the first measurement unit 227a, the positioning mechanism 23 is driven so that the image of the alignment mark is formed in the measurement range 42 of the second measurement unit 227b. As a result, an image of the alignment mark is formed in the measurement range 42 of the second measurement unit 227b.

  As described above, the imprint apparatus according to the second embodiment can achieve both alignment control accuracy and responsiveness.

  An imprint apparatus according to Embodiment 3 will be described. In addition, the block diagram in the alignment control in Example 3 is the same as FIG. 3 or FIG. First, the configuration of the alignment scope 22b will be described. FIG. 5 is a diagram illustrating a configuration of the alignment scope 22b. The same components as those in FIG. 2 are denoted by the same reference numerals, and description thereof is omitted. The difference from the alignment scope 22a is that a spatial light modulator 29 (spatial light modulation unit) that switches light between the relay lens 226b and the second measurement unit 227b, a first erector lens 228a, and a second erector lens 228b are configured. It is a point. A controller 30 that controls the spatial light modulator 29 is also configured. The spatial light modulator 29 has a plurality of light modulation elements corresponding to the pixels, and can switch ON / OFF of light projection for each light modulation element. For example, a DMD (digital micromirror device) or a liquid crystal element array can be adopted as the spatial light modulator 29.

Next, moire fringe signal processing when the spatial light modulator 29 is used will be described with reference to FIGS. FIG. 6 is a diagram illustrating a first integrated amount obtained by signal processing of moire fringes. Light from the alignment mark on the wafer 9 and the alignment mark on the mold 7 is guided to the light modulation element of the spatial light modulator 29. When all the pixels of the spatial light modulator 29 are turned on, when the signal intensity is extracted in the measurement direction based on the moire fringe image formed on the second measurement unit 227b, the moire signal 61 is a sign. Obtained as a wave. The horizontal axis represents pixels, and the vertical axis represents signal intensity. Next, the switching signal 62 is input to the spatial light modulator 29, and the range of the moire fringe imaged on the second measuring unit 227b is designated for each pixel. For example, the ON / OFF width of the switching signal 62 can be the width of the half cycle of the moire signal 61. As a result, only the ON pixel in the light modulation element of the spatial light modulator 29 is imaged on the second measurement unit 227 b, and is obtained as the imaging signal 63. The first integrated amount D ₁ is obtained by integrating the imaging signal 63.

FIG. 7 is a diagram illustrating a second integrated amount obtained by signal processing of moire fringes. A switching signal 72 having a phase opposite to that of the switching signal 62 is input to the spatial light modulator 29 to switch the range of the moire fringes that are imaged on the second measuring unit 227b. As a result, only pixels that are ON in the light modulation element of the spatial light modulator 29 are imaged on the second measurement unit 227 b, and an image formation signal 73 is obtained. Second cumulative amount D ₂ of light is obtained by integrating the imaging signal 73 obtained.

Next, the phase information of the moire signal 61 is enabled calculated by calculating the ratio of the first integrated quantity D ₁ with the acquired second integrated amount D _2. That is, since the phase information of the moire signal 61 changes depending on the relative positional relationship between the mold 7 and the wafer 9, the relative position information between the mold 7 and the wafer 9 can be calculated.

  In addition, the light receiving elements of the second measuring unit 227b may be arranged at a ratio of one for each half cycle of the moire signal 61, and the relative position between the mold 7 and the wafer 9 can be measured with a small number of light receiving elements. . In addition, the light receiving area of the light receiving element can be increased to achieve high sensitivity. Therefore, the second measurement unit 227b can measure the relative position between the mold 7 and the wafer 9 in a short measurement time.

  For example, consider a case where the alignment scope 22b is applied to the imprint apparatus according to the second embodiment. The measurement range of the first measurement unit 227a is a measurement range 41, and a CCD is employed as the light receiving element. Further, the measurement range of the second measurement unit 227b is set as the measurement range 42, and APD is adopted as the light receiving element. In this case, the measurement time of the first measurement unit 227a is approximately 28.6 times the measurement time of the second measurement unit 227b. Therefore, assuming that the control cycle of the conventional alignment control is 350 Hz, when the alignment scope 22b is applied to the imprint apparatus according to the second embodiment, the alignment control control cycle can be improved to about 10 KHz, and the alignment control response is improved. To do.

  As described above, the imprint apparatus according to the third embodiment can achieve both the accuracy of alignment control and the responsiveness.

(Product manufacturing method)
The pattern of the cured product formed using the imprint apparatus is used permanently on at least a part of various articles or temporarily used when manufacturing various articles. The article is an electric circuit element, an optical element, a MEMS, a recording element, a sensor, or a mold. Examples of the electric circuit elements include volatile or nonvolatile semiconductor memories such as DRAM, SRAM, flash memory, and MRAM, and semiconductor elements such as LSI, CCD, image sensor, and FPGA. Examples of the mold include an imprint mold.

  The pattern of the cured product is used as it is as a constituent member of at least a part of the article or temporarily used as a resist mask. After etching or ion implantation or the like is performed in the substrate processing step, the resist mask is removed.

  Next, a specific method for manufacturing an article will be described. As shown in FIG. 8A, a substrate 1z such as a silicon wafer on which a workpiece 2z such as an insulator is formed is prepared. Subsequently, the substrate 1z is formed on the surface of the workpiece 2z by an inkjet method or the like. A printing material 3z is applied. Here, a state is shown in which the imprint material 3z in the form of a plurality of droplets is applied on the substrate.

  As shown in FIG. 8B, the imprint mold 4z is opposed to the imprint material 3z on the substrate with the side having the concave / convex pattern formed thereon. As shown in FIG. 8C, the substrate 1 provided with the imprint material 3z is brought into contact with the mold 4z, and pressure is applied. The imprint material 3z is filled in a gap between the mold 4z and the workpiece 2z. In this state, when light is irradiated as energy for curing through the mold 4z, the imprint material 3z is cured.

  As shown in FIG. 8D, when the imprint material 3z is cured and then the mold 4z and the substrate 1z are separated, a pattern of a cured product of the imprint material 3z is formed on the substrate 1z. This cured product pattern has a shape in which the concave portion of the mold corresponds to the convex portion of the cured product, and the concave portion of the mold corresponds to the convex portion of the cured product, that is, the concave / convex pattern of the die 4z is transferred to the imprint material 3z. It will be done.

  As shown in FIG. 8 (e), when etching is performed using the pattern of the cured product as an etching resistant mask, the portion of the surface of the workpiece 2z where there is no cured product or remains thin is removed, and the grooves 5z and Become. As shown in FIG. 8 (f), when the pattern of the cured product is removed, an article in which the groove 5z is formed on the surface of the workpiece 2z can be obtained. Although the cured product pattern is removed here, it may be used as, for example, a film for interlayer insulation contained in a semiconductor element or the like, that is, a constituent member of an article without being removed after processing.

  As mentioned above, although preferred embodiment of this invention was described, it cannot be overemphasized that this invention is not limited to these embodiment, A various deformation | transformation and change are possible within the range of the summary. For example, the lithographic apparatus is not limited to an imprint apparatus that forms (forms) an imprint material on a substrate with a mold and forms a pattern on the substrate. The lithography apparatus may be an exposure apparatus that forms a pattern by exposing a substrate. Further, the lithography apparatus may be an apparatus such as a drawing apparatus that performs drawing on a substrate with a charged particle beam (such as an electron beam or an ion beam) via a charged particle optical system and forms a pattern on the substrate. Moreover, Example 1, Example 2, and Example 3 can be implemented not only independently, but also in combination of Example 1, Example 2, and Example 3.

Claims (17)

An alignment device for aligning an object,
A position detector for detecting the position of the mark of the object;
A moving unit for moving the object;
A control unit,
The position detection unit includes a first measurement unit and a second measurement unit that receive light from the mark and measure the position of the mark,
Each of the first measurement unit and the second measurement unit includes a light receiving element array for receiving the light and an optical system for imaging the light on the light receiving element array.
The position detector is
The second measurement unit is shorter than the first measurement unit in the measurement time, which is the time from when the light is received by the light receiving element array until the light is converted into a signal,
The second measurement unit has a narrower measurement range than the first measurement unit, in which the light is received by the light receiving element array and the light is converted into a signal.
The second measurement unit is shorter than the first measurement unit in the measurement time, which is the time from when the light is received by the light receiving element array until the light is converted into a signal, and the light is received by the light receiving element The measurement range, which is a range in which the light is received by the array and converted into a signal, is configured to be narrow,
The control unit acquires first position information of the object from the position of the mark measured by the first measurement unit, and obtains second position information of the object from the position of the mark measured by the second measurement unit. Using the elements other than the differential element of the deviation between the first position information and the target value for alignment and the differential element of the deviation between the second position information and the target value for alignment as inputs. An alignment apparatus that controls the moving unit to align an object. 2. The alignment apparatus according to claim 1, wherein an element other than a differential element of a deviation between the first position information and the alignment target value includes one or both of a proportional element and an integral element. . The position detection unit has a separation unit for separating light,
The separation unit separates light from the mark into a plurality of lights, the first measurement unit measures one of the plurality of lights, and the second measurement unit measures another one of the plurality of lights. The alignment apparatus according to claim 1 or 2, characterized in that Having a drive unit mounted and driven by the position detection unit;
The drive unit drives the position detection unit based on a measurement result of the first measurement unit so that a measurement range of the second measurement unit is within a range in which the mark can be measured. The alignment apparatus according to any one of claims 3 to 3. An alignment device for aligning a first object and a second object,
A position detection unit for detecting a relative position between the first mark of the first object and the second mark of the second object;
A moving unit for moving the first object or the second object;
A control unit,
The position detection unit includes a first measurement unit and a second measurement unit that receive light from the first mark and the second mark and measure the position of the first mark and the position of the second mark. Prepared,
Each of the first measurement unit and the second measurement unit includes a light receiving element array for receiving the light and an optical system for imaging the light on the light receiving element array.
The position detector is
The second measurement unit is shorter than the first measurement unit in the measurement time, which is the time from when the light is received by the light receiving element array until the light is converted into a signal,
The second measurement unit has a narrower measurement range than the first measurement unit, in which the light is received by the light receiving element array and the light is converted into a signal.
The second measurement unit is shorter than the first measurement unit in the measurement time, which is the time from when the light is received by the light receiving element array until the light is converted into a signal, and the light is received by the light receiving element The measurement range, which is a range in which the light is received by the array and converted into a signal, is configured to be narrow,
The control unit obtains first relative position information of the first object and the second object from a relative position between the marks measured by the first measurement unit, and between the marks measured by the second measurement unit. Second relative position information of the first object and the second object is obtained from the relative position of the first object, elements other than the differential element of the deviation between the first relative position information and the target value of the alignment, and the second An alignment apparatus that controls the moving unit by using relative position information and a differential element of deviation between the alignment target values as inputs. 6. The alignment according to claim 5, wherein the elements other than the differential element of the deviation between the first relative position information and the alignment target value include one or both of a proportional element and an integral element. apparatus. The position detection unit has a separation unit for separating light,
The separation unit separates light from the first mark and the second mark into a plurality of lights, the first measurement unit measures one of the plurality of lights, and the second measurement unit includes the plurality of lights. The alignment apparatus according to claim 5, wherein the other one of the lights is measured. Having a drive unit mounted and driven by the position detection unit;
The drive unit drives the position detection unit based on the measurement result of the first measurement unit so that the measurement range of the second measurement unit is within a range in which the first mark and the second mark can be measured. The alignment apparatus according to any one of claims 5 to 7, characterized in that:   The alignment apparatus according to any one of claims 5 to 8, wherein the first mark and the second mark are marks having a lattice pattern that generates moire fringes. The position detection unit includes a spatial light modulation unit that modulates light from the first mark and the second mark,
The second measurement unit measures the light modulated by the spatial light modulation unit, and detects the relative position between the first mark and the second mark from a value obtained by integrating the signal obtained by converting the light. The alignment apparatus according to claim 9, wherein:   11. The alignment according to claim 10, wherein the light receiving element array of the second measurement unit includes a light receiving element for each half cycle of a signal obtained by converting light from the first mark and the second mark. apparatus.   The alignment apparatus according to claim 1, wherein the light receiving element array of the second measurement unit includes an avalanche photodiode as a light receiving element.   The alignment apparatus according to claim 1, wherein the light receiving element array of the second measurement unit includes a line sensor in which the light receiving elements are arranged on a line.   The control period for controlling the moving unit is a time from when the light receiving element array of the second measuring unit receives the light until the control unit obtains the differential element. The alignment apparatus according to any one of claims 1 to 13. A position detection device for detecting the position of an object mark,
A first measurement unit and a second measurement unit for measuring light from the mark;
A separation unit for separating the light;
A spatial light modulator that modulates the light,
Each of the first measurement unit and the second measurement unit includes a light receiving element array for receiving the light and an optical system for imaging the light on the light receiving element array.
The second measurement unit is shorter than the first measurement unit in the measurement time, which is the time from when the light is received by the light receiving element array to when the light is converted into a signal,
The second measurement unit has a narrower measurement range than the first measurement unit, in which the light is received by the light receiving element array and the light is converted into a signal.
The second measurement unit is shorter than the first measurement unit in the measurement time, which is the time from when the light is received by the light receiving element array until the light is converted into a signal, and the light is received by the light receiving element The measurement range, which is a range in which the light is received by the array and converted into a signal, is configured to be narrow,
The light is separated into a plurality of lights by the separation unit, the first measurement unit measures one of the plurality of lights, the second measurement unit measures the other one of the plurality of lights,
The mark is a mark of a lattice pattern that causes moire fringes,
The second measurement unit has a light receiving element for each half cycle of the signal obtained by converting the light, is obtained by measuring the light modulated by the spatial light modulation unit, and integrating the signal obtained by converting the light. A position detecting device for detecting the position of the mark from the obtained value. A lithographic apparatus for forming a pattern on a substrate,
A lithographic apparatus, comprising the alignment apparatus according to claim 1. Forming a pattern on a substrate using the lithographic apparatus according to claim 16;
Processing the substrate on which the pattern has been formed in the step;
A method for producing an article comprising: