JP6039770B2 - Imprint apparatus and device manufacturing method - Google Patents

Description

  The present invention relates to a mark detection system in an imprint apparatus for transferring a mold pattern onto an imprint material on a substrate.

  The demand for miniaturization of semiconductor devices has advanced, and in addition to the conventional photolithography technology, an imprint pattern is formed by bringing a fine pattern formed on a mold into contact with (imprinting) an imprint material supplied on a substrate. Printing technology is attracting attention.

  An optical imprint method will be described as an example of the imprint technique. First, a layer made of a photo-curing resin (hereinafter, imprint resin) is formed on a substrate (for example, a semiconductor wafer). Next, the imprint resin is brought into contact with a mold on which a desired fine uneven structure (pattern) is formed. Next, the imprint resin is cured by irradiating with ultraviolet rays while the imprint resin and the mold are in contact with each other. After the imprint resin is cured, a pattern is formed on the substrate by separating the imprint resin and the mold.

  In the imprint apparatus, alignment is performed for each shot before the mold and the imprint resin are brought into contact with each other. In the alignment of the imprint apparatus, a through-the-mold detection system (hereinafter referred to as a TTM detection system) capable of simultaneously detecting and aligning marks formed on the mold and the wafer is used. In Patent Document 1, an illumination system for irradiating the resin layer with ultraviolet rays through the mold from the upper part of the mold is arranged on the upper part of the mold, and a TTM detection system is arranged so as to avoid the illumination system. An imprint apparatus is described.

JP 2005-286062 A

  Since the TTM detection system is disposed so as to avoid interference with the illumination system and the illumination light beam, the TTM detection system has to be disposed with an inclination with respect to the optical axis of the illumination system. In order to align the wafer with a TTM detection system that is tilted with respect to the optical axis of the illumination system, the TTM detection system has a Littrow arrangement and detects signals by capturing light diffracted at a Littrow angle. It was. However, in the TTM detection system arranged in the Littrow arrangement, the detection numerical aperture (hereinafter referred to as NA) of the TTM detection system cannot be sufficiently increased due to the arrangement restriction, so that the detection accuracy is small and the alignment accuracy is lowered. There was a problem.

  An object of the present invention is to increase the detection numerical aperture of the TTM detection system and improve the alignment accuracy between the substrate and the mold.

An imprint apparatus according to the present invention is an imprint apparatus that forms a pattern of an imprint material on a substrate using a mold, and includes a light receiving element and imaging optics that forms an image of the surface of the substrate on an imaging surface. System, a detection optical system that guides light from a mark formed on the substrate and a mark formed on the mold through the imaging optical system to the light receiving element, and the detection optical system is moved along the imaging plane And a light-receiving element that detects light from a mark formed on the substrate and a mark formed on the mold, and aligns the substrate and the mold based on the detection result.

  According to the present invention, the detection numerical aperture of the TTM detection system can be increased and the alignment accuracy between the substrate and the mold can be improved.

It is a figure which shows schematically the imprint apparatus of 2nd Embodiment of this invention. It is a figure which shows schematically the imprint apparatus of 3rd Embodiment of this invention. 1 is a diagram schematically illustrating an imprint apparatus according to a first embodiment of the present invention. It is a figure which shows schematically the imprint apparatus of 4th Embodiment of this invention. It is a figure which shows schematically the imprint apparatus of 5th Embodiment of this invention. It is a figure which shows schematically the imprint apparatus of 6th Embodiment of this invention. It is a figure which shows a board | substrate and an alignment mark. It is a figure which shows the imprint technique schematically. It is a figure which shows the conventional imprint apparatus schematically.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described with reference to the accompanying drawings. In addition, in each figure, the same reference number is attached | subjected about the same member and the overlapping description is abbreviate | omitted.

[First Embodiment]
FIG. 9 is a diagram schematically showing a configuration of a conventional imprint apparatus 1. As shown in FIG. 9, the imprint apparatus 1 includes an illumination system 2 that irradiates illumination light 3 (mainly ultraviolet rays) to cure the imprint resin, an imprint head 4 that holds a mold 5 as a mold, and a substrate. The wafer stage 9 holding the wafer 8 is provided. Further, the imprint apparatus 1 includes a TTM detection system 7, a resin application mechanism 6, and a control unit 10.

  The TTM detection system 7 can detect a mold alignment mark (not shown) formed on the mold 5 and a wafer alignment mark (not shown) formed on the wafer 8. Based on the detection result of the alignment mark, the mold 5 and the wafer 8 can be aligned. The TTM detection system 7 irradiates the mold alignment mark and the wafer alignment mark with measurement light 11 (mainly visible light or infrared light) using a light source provided therein, and detects the reflected light. The TTM detection system 7 includes a photoelectric conversion element (for example, a CCD) as a light receiving element for detecting reflected light.

  At this time, the relative positional relationship (X, Y, Z) between the mold 5 and the wafer 8 can be adjusted by adjusting the position and focus of the mold alignment mark and the wafer alignment mark. The detection result of the TTM detection system 7 is output to the control unit 10, and the control unit 10 controls the wafer stage 9 or the imprint head 4 in the X and Y directions based on the detection result of the TTM detection system 7, so that the mold 5 or wafer 8 can be adjusted in the XY direction.

  In the position measurement of the mold 5 and the wafer 8 by the TTM detection system 7, the imprint resin is supplied to the upper part of the wafer alignment mark, so that interference fringes are generated in monochromatic light. Therefore, it is detected in a state where the interference fringe signal is added to the alignment signal, and cannot be detected with high accuracy. In addition, when light in the ultraviolet region is used as the measurement light 11, the imprint resin supplied to the upper portion of the wafer alignment mark is exposed. Therefore, generally, as the illumination light source of such a TTM detection system 7, a light source having a broad band and a wavelength of non-exposure light is used, and it is detected as a signal with less interference fringes. Here, the non-exposure light means light having a wavelength different from that of light irradiated for curing the imprint resin.

  When the alignment between the mold 5 and the wafer 8 is completed, the pattern formed on the mold is transferred. An imprint resin is supplied to the wafer 8 using the resin coating mechanism 6. The imprint head 4 moves while holding the mold 5 to bring the imprint resin supplied to the wafer 8 into contact with the pattern formed on the mold 5 (imprinting). In this state, illumination light 3 (ultraviolet rays) is irradiated from the illumination system 2 in order to cure the imprint resin. When the imprint resin is cured, the mold 5 and the cured imprint resin are separated (release).

  A pattern transfer method using an imprint technique using the imprint apparatus 1 will be described with reference to FIG. A pattern 13 to be transferred to the imprint resin on the substrate is formed on the mold 5.

  First, as shown in FIG. 8A, the resin coating mechanism 6 supplies an imprint resin 14 as an imprint material onto the wafer 8. Here, a description will be given using a photo-curing resin that cures when irradiated with light. The wafer stage 9 moves so that the wafer 8 supplied with the imprint resin 14 is positioned directly under the mold 5 as shown in FIG. 8B. When the wafer 8 supplied with the imprint resin 14 comes directly under the mold 5, the mold 5 is pressed against the imprint resin 14 on the wafer 8 as shown in FIG. Here, the case where the mold 5 is pressed against the imprint resin has been described. However, the imprint resin 14 supplied to the wafer 8 by moving the wafer chuck may be pressed against the mold 5. Further, the mold 5 and the wafer 8 may be pressed against each other.

  In a state where the mold 5 is pressed, the illumination system 2 emits ultraviolet rays 15 for curing the imprint resin 14. When the imprint resin 14 is cured, the mold 5 is pulled away from the imprint resin 14 as shown in FIG. Then, the pattern 13 formed on the mold 5 is transferred to the imprint resin 14, and a pattern 16 that is the reverse of the pattern 13 can be formed.

  Then, the wafer stage 9 is moved, and the imprint resin is supplied to the next shot to transfer the pattern. In this way, by repeating the stamping and releasing on the shots on the wafer, the fine pattern 16 can be formed on all the shots on the wafer 8.

  However, a force is applied to the wafer 8 by the stamping and releasing of the mold 5. When the force is applied, the position of the wafer 8 may be displaced with respect to the wafer stage 9 as shown in FIG. This is because, unlike the conventional light exposure apparatus, the mold (mold) and the imprint resin supplied on the substrate (wafer) come into contact with each other. If the mold is imprinted with the next shot while the wafer 8 is displaced with respect to the wafer stage 9 as shown in FIG. 7A, the overlay with the underlying pattern does not work well and the device yield decreases. It becomes a cause. Therefore, there is an alignment method (die-by-die alignment) that corrects wafer displacement by performing mold imprinting and mold release on a shot and measuring the alignment mark 12 of that shot before imprinting the next shot. It becomes necessary. In die-by-die alignment, by measuring the shot alignment mark 12 for each shot and correcting the deviation of the wafer 8, it is possible to reduce the influence of wafer deviation caused by mold stamping and mold release. And can be superimposed with high accuracy.

  However, in the conventional imprint apparatus 1 shown in FIG. 9, the TTM detection system 7 is arranged so as to avoid the illumination light flux of the illumination system 2 and the illumination light 3. For this reason, there is a problem that the NA of the TTM detection system 7 cannot be sufficiently increased. The NA 45 of the TTM detection system 7 depends on the size of the TTM detection system 7 itself. In the TTM detection system 7 arranged so as to avoid the illumination light flux of the illumination system 2 and the illumination light 3, the TTM detection system 7 is The size cannot be increased and the NA45 cannot be increased.

  If the NA of the TTM detection system 7 cannot be made sufficiently large, the amount of light during alignment will decrease, leading to a decrease in alignment accuracy. Since the TTM detection system 7 detects and aligns the alignment mark formed on the mold 5 and the alignment mark formed on the wafer 8 at the same time, the TTM detection system 7 must be placed on the mold 5. However, since the upper part of the mold 5 is crowded in terms of arrangement, the conventional imprint apparatus 1 has a problem that the NA of the TTM detection system 7 cannot be increased and the alignment accuracy is lowered. If the alignment accuracy of the TTM detection system 7 is lowered, it becomes impossible to accurately correct the wafer misalignment at the time of die-by-die alignment. This will cause the yield to decrease.

  Therefore, the present invention is characterized by providing an imprint apparatus in which the NA of the TTM detection system for directly aligning the mold 5 and the wafer 8 can be increased and the alignment accuracy is improved. As a result, the pattern formed on the mold 5 and the shot area of the wafer 8 can be overlaid with high accuracy, contributing to an improvement in yield.

  FIG. 3 is a diagram schematically showing the configuration of the imprint apparatus 17 according to the first embodiment. FIG. 3 shows an imprint apparatus 17 characterized in that a relay optical system 18 is formed on the upper part (Z-axis direction) of the mold 5. As shown in FIG. 3, the imprint apparatus 17 according to the first embodiment includes a wafer stage 9 that holds a wafer 8, an imprint head 4 that holds a mold 5, a resin coating mechanism 6, and a control unit 10. Up to this point, the configuration is the same as that of the conventional imprint apparatus shown in FIG.

  In the relay optical system 18, an in-relay optical system lens 49 is configured, and an imaging surface 47 (conjugate surface) on which the wafer surface is imaged can be created on the upper part of the mold 5. The relay optical system has a function of forming an image of the wafer surface through a mold. If the image of the wafer surface is formed, the magnification of the relay optical system may be the same or an enlargement system. Here, it is desirable that the screen size of the relay optical system (the area of the wafer surface to be imaged) is the entire surface of one shot area. By imaging the entire shot area, a plurality of marks corresponding to the shot can be detected. Further, the screen size of the relay optical system can be set to be equal to or larger than the illumination light region in which the illumination system described later irradiates the imprint material on the substrate. By doing so, it is possible to form an image of the mark formed outside the region to which the pattern formed on the mold is transferred by the relay optical system. The formed mark is guided to the light receiving element by the detection system (detection optical system), thereby performing mark detection.

  The TTM detection system 19 irradiates measurement light 11 (mainly visible light or infrared light) to the alignment mark formed on the mold 5 and the alignment mark formed on the wafer 8 using a light source provided therein, and the reflection thereof. Detect light. Although the above-described TTM detection system 7 has been described as including a light receiving element, here, the TTM detection system 19 and the light receiving element 46 will be described as being different.

  The TTM detection system 19 is disposed above the relay optical system 18, and the measurement light 11 emitted from the TTM detection system 19 passes through the relay optical system lens 49 in the relay optical system 18, and the mold 5 and the wafer 8. Irradiate. Reflected light from the alignment mark formed on the mold 5 and the alignment mark formed on the wafer 8 passes through the relay optical system 18 and the TTM detection system 19 and is detected by the light receiving element 46 for the TTM detection system. The mold 5 and the wafer 8 can be aligned based on the detection signal. As the light receiving element 46, a photoelectric conversion element (for example, a CCD camera) may be used. In particular, when the mold 5 and the wafer 8 are close to or in close contact with each other, the light reflected from the alignment mark formed on the mold 5 and the alignment mark formed on the wafer 8 is guided to the light receiving element. By doing so, the mold 5 and the wafer 8 can be aligned before the imprint material is cured.

  As shown in FIG. 3, by arranging the relay optical system 18 on the upper part of the mold 5, the arrangement place of the TTM detection system 19 can be set up to a space where there is room in the arrangement by avoiding the crowding on the upper part of the mold 5. Can be moved. As shown in FIG. 3, by arranging the TTM detection system 19 in a space with a sufficient arrangement, the TTM detection system 19 can be arranged even if it is enlarged, and the NA of the TTM detection system 19 can be increased. The NA 52 of the TTM detection system 19 in FIG. 3 can be made sufficiently larger than the NA 45 of the TTM detection system 7 in FIG. Since the NA 52 of the TTM detection system 19 can be increased, a sufficient amount of light can be secured during alignment. Therefore, in the imprint apparatus 17 of the present embodiment, the accuracy of die-by-die alignment is improved as compared with the conventional case. Therefore, the imprint apparatus 17 according to the present embodiment can correct the positional deviation of the wafer that occurs when the mold 5 and the wafer 8 are imprinted / released with high accuracy. You can superimpose. Therefore, it can contribute to the improvement of device yield.

  The illumination system 20 of the imprint apparatus 17 according to the present embodiment can be arranged to be inclined with respect to the optical axis of the measurement light 11 from the TTM detection system 19 instead of directly above the mold 5 as shown in FIG. With this arrangement, the illumination light 3 from the illumination system 20 can be irradiated with light to cure the imprint resin after the mold 5 and the wafer 8 are imprinted. The imprint resin can be irradiated through the mold 5. Therefore, the relay optical system 18 in FIG. 3 does not allow the illumination light 3 (ultraviolet light) from the illumination system 20 to pass. Therefore, the relay optical system of this embodiment is also characterized in that it is a relay lens on which light (non-exposure light) different from the illumination light 3 forms an image.

[Second Embodiment]
A second embodiment will be described with reference to FIG.

  In the imprint apparatus 17 of FIG. 3, the illumination system 20 is tilted with respect to the optical axis of the measurement light 11 from the TTM detection system 19, but the illumination system is not tilted if possible and is perpendicular to the wafer 8. It is desirable to make the illumination light incident on. Therefore, in the second embodiment, both the TTM detection system with high NA capable of realizing high alignment accuracy and the illumination system are arranged on the upper part of the mold, and both the measurement light and the illumination light can be incident on the wafer surface perpendicularly. An imprint apparatus characterized by the above will be described.

  FIG. 1 is a schematic block diagram of an imprint apparatus 21 in which a relay optical system 23 having a beam splitter 22 is arranged on the upper part of a mold. As shown in FIG. 1, the imprint apparatus 21 includes a wafer stage 9 that holds a wafer 8, an imprint head 4 that holds a mold 5, a resin coating mechanism 6, and a control unit 10. Up to this point, the configuration is the same as that of the imprint apparatus shown in FIG.

  The TTM detection system 19 is disposed via the relay optical system 23. The measurement light 11 irradiated from the TTM detection system 19 passes through the relay optical system lens 49, the beam splitter 22, and the relay optical system lens 49 included in the relay optical system 23, and irradiates the mold 5 and the wafer 8. Is done. Reflected light from the alignment mark formed on the mold 5 and the alignment mark formed on the wafer 8 passes through the relay optical system 23 and the TTM detection system 19 and is detected by the light receiving element 46 for the TTM detection system. The mold 5 and the wafer 8 can be aligned based on the detection signal. An imaging surface 47 on which the wafer surface is imaged is formed on the upper part of the mold 5 by the relay optical system lens 49 configured in the relay optical system 23. The TTM detection system 19 can have the same configuration as the TTM detection system 19 of FIG.

  The relay optical system 23 can form an imaging surface 47 on the surface of the substrate through a mold. The screen size of the relay optical system 23 (the area of the wafer surface on which the image is formed) can be the entire shot area as in the relay optical system 18 of the first embodiment. Moreover, it can be more than the area | region of the illumination light in which an illumination system illuminates the imprint material. It is only necessary to determine the size of the screen of the relay optical system 23 so that alignment marks formed on the substrate corresponding to at least shots are simultaneously imaged.

  The TTM detection system 19 of the imprint apparatus 21 shown in FIG. 1 is arranged in a space having a margin in arrangement, avoiding crowding in the arrangement of the upper part of the mold as in FIG. For this reason, even if the TTM detection system 19 is enlarged, it can be arranged, and the NA of the TTM detection system 19 can be increased. The NA 52 of the TTM detection system 19 of FIG. 1 can be made sufficiently larger than the NA 45 of the TTM detection system 7 of the conventional imprint apparatus shown in FIG. Since the NA 52 of the TTM detection system 19 can be increased, a sufficient amount of light can be secured during alignment. Therefore, in the imprint apparatus 21 of the second embodiment, the accuracy of die-by-die alignment is improved as compared with the conventional one. Therefore, the imprint apparatus 21 according to the second embodiment can correct the positional deviation of the wafer that occurs when the mold 5 and the wafer 8 are imprinted / released with high accuracy. Can be superimposed on each other. Therefore, it can contribute to the improvement of device yield.

  As with the TTM detection system 19, the illumination system 24 of the imprint apparatus 21 according to the second embodiment is arranged in a space that has a sufficient layout margin while avoiding crowding in the layout of the upper part of the mold. The illumination light 3 emitted from the illumination system 24 is guided to the beam splitter 22 through the illumination system lens 48 and then reflected by the beam splitter 22. The reflected illumination light 3 passes through the relay optical system inner lens 49 and the mold 5 and can irradiate the imprint resin supplied to the wafer 8. The imprint resin is cured when irradiated with the illumination light 3. The beam splitter 22 is partially in common with the illumination system 24.

  As described above, in the imprint apparatus according to the second embodiment, the relay optical system 23 including the beam splitter 22 is configured in the upper part of the mold, so that both the TTM detection system 19 and the illumination system 24 have a sufficient space in terms of arrangement. It is possible to arrange.

  The relay optical system 23 is a telecentric optical system (off-axis principal ray parallel to the optical axis) that forms an image of the entire shot surface with light (non-exposure light) different from the illumination light 3. As described above, the relay optical system 23 can simultaneously image a plurality of alignment marks. Therefore, by configuring the TTM detection system 19 to be movable and changing its position, each point of the plurality of alignment marks can be measured. If the relay optical system 23 is a telecentric optical system, the off-axis principal ray is parallel to the optical axis, so that there is an advantage that the means for changing the image height of the TTM detection system 19 becomes easy. FIG. 1 shows an example in which three points on the wafer 8 are imaged on the image plane 47 of the wafer surface. By changing the position of the TTM detection system 19, different points on the wafer shot can be measured. I understand. For the sake of simplicity, the refraction of the light beam in the beam splitter 22 is not shown in FIG. 1, but actually the beam other than the axial light beam of the relay optical system 23 that enters the beam splitter 22 perpendicularly passes through the beam splitter 22. Shift slightly when you do.

[Third Embodiment]
A third embodiment will be described with reference to FIG.

  As in the above-described embodiment, the relay optical system is arranged between the detection system and the mold. The detection system irradiates measurement light in the order of the mold and the wafer via the relay optical system, and detects the reflected light of the alignment mark formed on the mold and the alignment mark formed on the wafer. Based on the detection result, the positional deviation between the mold and the wafer is detected and the position can be aligned.

  The beam splitter 22 described in the second embodiment has a characteristic of transmitting the measurement light 11 of the TTM detection system 19 and reflecting the illumination light 3 emitted from the illumination system 24. However, the characteristics of the beam splitter may be reversed.

  The imprint apparatus according to the third embodiment uses a beam splitter 26 having a characteristic of reflecting the measurement light 11 of the TTM detection system 19 and transmitting the illumination light 3 emitted from the illumination system 24. FIG. 2 is a schematic block diagram of the imprint apparatus 25 including the beam splitter 26.

  The measurement light 11 emitted from the TTM detection system 19 is transmitted through the TTM detection system lens 50, guided to the beam splitter 26, and then reflected by the beam splitter 26. The reflected measurement light 11 passes through the relay optical system inner lens 49 and irradiates the mold 5 and the wafer 8. Reflected light from the alignment mark formed on the mold 5 and the alignment mark formed on the wafer 8 passes through the TTM detection system 19 and is detected by the light receiving element 46 for the TTM detection system. The mold 5 and the wafer 8 can be aligned based on the detection signal.

  The relay optical system 23 can have the same configuration as the relay optical system 23 described in the second embodiment. However, since the measurement light 11 is reflected by the beam splitter 26, the imaging surface 47 of the wafer surface (wafer surface) is formed by the relay optical system inner lens 49 and the TTM detection system lens 50 configured in the relay optical system 23. It is formed. Thus, the image plane 47 of the wafer surface is formed on the upper part of the mold 5. The TTM detection system 19 can have the same configuration as the TTM detection system 19 of FIG.

  The screen size of the relay optical system (the area of the wafer surface to be imaged) can be the entire shot area as in the relay optical system 18 of the first embodiment. Moreover, it can be more than the area | region of the illumination light in which an illumination system illuminates the imprint material. The screen size of the relay optical system may be determined so that at least the alignment marks formed on the substrate corresponding to the shot are imaged simultaneously.

  The illumination light 3 emitted from the illumination system 24 passes through the relay optical system lens 49, the beam splitter 26, and the relay optical system lens 49 provided in the relay optical system 23, passes through the mold 5, and onto the wafer 8. Illuminate the supplied imprint resin. The imprint resin is cured when irradiated with the illumination light 3.

  As described above, the imprint apparatus 25 according to the third embodiment includes the beam splitter 26 having a characteristic of reflecting the measurement light 11 and transmitting the illumination light 3. In this way, as in the second embodiment, it is possible to arrange the TTM detection system 19 and the illumination system 24 having a high NA capable of realizing high alignment accuracy on the mold.

  The imprint apparatus shown in FIG. 2 is characterized in that the relay optical system includes a beam splitter 26 having a characteristic of reflecting measurement light from the TTM detection system and transmitting illumination light from the illumination system. The characteristics of this beam splitter need not be perfect reflection or perfect transmission. For example, it may be a beam splitter that reflects 90% of measurement light from the TTM detection system and transmits 10%. Further, it may be a beam splitter that transmits 90% of the illumination light from the illumination system and reflects 10%. It is assumed that the ratio of reflection and transmission of the beam splitter is not 9: 1 but may be 8: 2 or 7: 3.

[Fourth Embodiment]
A fourth embodiment will be described with reference to FIG.

  As shown in FIGS. 1 and 2, in the imprint apparatus constituting the relay optical system including the beam splitter, both the TTM detection system and the illumination system can be arranged on the mold, and the NA of the TTM detection system can be arranged. There is an advantage that it can raise enough. However, it may be difficult to obtain the characteristics of the beam splitter provided in the relay optical system. Even if the characteristics can be obtained, the cost of the beam splitter may be high. Further, in the relay optical system that does not include the beam splitter as shown in FIG. 3, although the NA of the TTM detection system can be sufficiently raised and placed on the mold, the illumination system is in relation to the optical axis of the TTM detection system. Must be placed diagonally.

  Therefore, as a fourth embodiment, an imprint apparatus constituting a relay optical system that does not include a beam splitter will be described. It is characterized in that both a TTM detection system and an illumination system having a sufficiently large NA are arranged on the mold and switched.

  FIG. 4 is a schematic block diagram of an imprint apparatus 27 that switches between the TTM detection system and the illumination system of the fourth embodiment. As shown in FIG. 4, the imprint apparatus 27 according to the fourth embodiment includes a wafer stage 9 that holds a wafer 8, an imprint head 4 that holds a mold 5, a resin coating mechanism 6, and a control unit 10. Up to this point, the configuration is the same as that of the imprint apparatus described in the above embodiment.

  The TTM detection system 28 and the illumination system 29 are arranged with respect to the mold 5 and the wafer 8 via the relay optical system 30 and are each provided with a drive mechanism (not shown). At the time of alignment, as shown in FIG. 4A, the measurement light 11 irradiated from the TTM detection system 28 passes through the relay optical system inner lens 49 formed in the relay optical system 30 and irradiates the mold 5 and the wafer 8. . Reflected light from the alignment mark formed on the mold 5 and the alignment mark formed on the wafer 8 passes through the relay optical system 30 and the TTM detection system 28 and is detected by the light receiving element 46 for the TTM detection system. The mold 5 and the wafer 8 can be aligned based on the detection signal.

  The relay optical system 30 can form an imaging surface 47 on the surface of the wafer through a mold. The screen size of the relay optical system (the area of the wafer surface to be imaged) can be the entire shot area as in the relay optical system 18 of the first embodiment. Moreover, it can be more than the area | region of the illumination light in which an illumination system illuminates the imprint material. The size of the screen of the relay optical system 30 may be determined so that at least the alignment marks formed on the substrate corresponding to the shot are imaged simultaneously. An imaging surface 47 of the wafer surface (wafer surface) is formed by the relay optical system inner lens 49 configured in the relay optical system 30. Thus, the image plane 47 of the wafer surface is formed on the upper part of the mold 5. The TTM detection system 28 can have the same configuration as the TTM detection system 19 in FIG.

  When the illumination system 29 illuminates the wafer 8, the positions of the TTM detection system 28 and the illumination system 29 are switched as shown in FIG. The illumination light 3 emitted from the illumination system 29 passes through the relay optical system inner lens 49 and the mold 5 that are configured in the relay optical system 30, and irradiates the imprint resin supplied to the wafer 8. The imprint resin is cured when irradiated with the illumination light 3.

  Thus, in the imprint apparatus 27 that switches the arrangement of the TTM detection system 28 and the illumination system 29, the relay optical system 30 is not provided with a beam splitter, and the TTM detection system and illumination system with a sufficiently high NA are provided above the mold. It becomes possible to arrange.

[Fifth Embodiment]
A fifth embodiment will be described with reference to FIG.

  In the embodiment described above, the TTM detection system has been described with a single system configuration for the sake of simplicity. However, the TTM detection system may have a plurality of systems. For example, when it is desired to simultaneously measure alignment marks formed at a plurality of locations on a shot during die-by-die alignment, it is desirable to have a plurality of TTM detection systems. Even if there is only one TTM detection system, it is possible to measure alignment marks formed at a plurality of locations on a shot by moving the stage or moving the TTM detection system. However, since the stage or the detection system is moved, there is a problem that the alignment accuracy is likely to be lowered and the throughput is also lowered. On the mold, the arrangement is crowded, and it has been difficult to arrange a plurality of TTM detection systems on the mold.

  Therefore, the fifth embodiment is characterized in that a plurality of TTM detection systems having a sufficiently large NA are arranged on the mold by arranging a relay optical system on the mold.

  FIG. 5 is a schematic block diagram of an imprint apparatus including a plurality of TTM detection systems according to the fifth embodiment. As shown in FIGS. 5A to 5C, the imprint apparatus according to the fifth embodiment includes a wafer stage 9 that holds a wafer 8, an imprint head 4 that holds a mold 5, a resin coating mechanism 6, and a control. The unit 10 is provided. Up to this point, the configuration is the same as that of the imprint apparatus described in the above embodiment.

  FIG. 5A shows a schematic block diagram of an imprint apparatus 31 in which two TTM detection systems are arranged on the upper part of the mold 5. The relay optical system 34 is formed on the upper part of the mold 5, and the TTM detection system can be arranged in a space having a sufficient arrangement while avoiding the crowding of the arrangement on the upper part of the mold. In FIG. 5A, the TTM detection system 32 and the TTM detection system 33 are arranged in a space having a sufficient arrangement, and a high alignment accuracy can be realized by a TTM detection system having a sufficiently large NA.

  By constructing two TTM detection systems, two different alignment marks on the same shot can be detected simultaneously, and highly accurate alignment measurement can be realized. For example, if an alignment mark in the X direction and an alignment mark in the Y direction are detected, the alignment measurement in the X direction and the alignment measurement in the Y direction can be performed simultaneously. Further, the shot shape can be corrected by detecting two different alignment marks in the shot.

  Further, the relay optical system 34 of the fifth embodiment is a telecentric optical system that forms an image of the entire shot surface with light (non-exposure light) different from the illumination light 3, and a plurality of TTM detection systems can be arranged. It is. The relay optical system 34 can form an imaging surface 47 on the surface of the wafer through a mold. The relay optical system 34 can have the same configuration as the relay optical system 18 described in the first embodiment. Further, the relay optical system 34 may have the same configuration as the relay optical system 23 described in the second embodiment or the third embodiment. By inserting a beam splitter into the relay optical system, the optical path of the illumination light 3 irradiated by the illumination system 24 and a part of the measurement light 11 can be made common.

  Further, the relative positions of the TTM detection system 32 and the TTM detection system 33 in FIG. 5A are variable. By changing the positions of the TTM detection system 32 and the TTM detection system 33, each point of the wafer shot can be measured. The screen size of the relay optical system (region of the wafer surface to be imaged) can be determined by determining the screen size of the relay optical system so that at least a plurality of alignment marks formed on the substrate are imaged simultaneously. Good.

  The measurement light 11 irradiated from the TTM detection system 32 and the TTM detection system 33 passes through the relay optical system 34 and irradiates the mold 5 and the wafer 8. Reflected light from the alignment mark formed on the mold 5 and the alignment mark formed on the wafer 8 passes through the relay optical system 34, the TTM detection system 32, and the TTM detection system 33, and is detected by the light receiving element 46 for the TTM detection system. The The mold 5 and the wafer 8 can be aligned based on the detection signal. An imaging surface 47 on which the wafer surface is imaged is formed on the upper part of the mold 5 by the relay optical system lens 49 configured in the relay optical system 34. The TTM detection systems 32 and 33 can have the same configuration as the TTM detection system 19 in FIG.

  In the imprint apparatus 31 of this embodiment, the illumination system 35 may irradiate the illumination light 3 to the imprint resin supplied to the wafer after the mold 5 and the wafer 8 are imprinted. For this reason, the illumination system 35 may be arranged not to be directly above the mold 5 but to be inclined with respect to the optical axis of the measurement light 11 from the TTM detection system 32 or the TTM detection system 33. With this arrangement, the illumination light 3 from the illumination system 35 can pass through the mold 5 after imprinting the mold 5 and the wafer 8 and irradiate the imprint resin supplied to the wafer 8. The imprint resin is cured when irradiated with the illumination light 3. As described above, the relay optical system 34 in FIG. 5A does not pass the illumination light 3 (ultraviolet rays) from the illumination system 35. Therefore, the relay optical system of this embodiment is also characterized in that it is a relay lens on which light (non-exposure light) different from the illumination light 3 forms an image.

  In the description of FIG. 5A, the imprint apparatus in which two systems are arranged as a plurality of TTM detection systems has been described. However, if there are a plurality of systems, the TTM detection system may be three systems or four systems instead of two systems.

  FIG. 5B shows a schematic block diagram of an imprint apparatus 36 in which four TTM detection systems are arranged on the upper part of the mold 5. In the fifth embodiment, the relay optical system 34 is configured on the mold, and the TTM detection system can be arranged in a space having a sufficient arrangement. Therefore, the TTM detection system can be arranged not only in the vertical direction (Z direction) but also in the horizontal direction (X direction, Y direction).

  The TTM detection system of the imprint apparatus 36 includes a TTM detection system 37 and a TTM detection system 38 in the Y direction in addition to the TTM detection system 32 and the TTM detection system 33 arranged in the same Z direction as in FIG. In total, four systems are arranged. Here, the TTM detection system 32 and the TTM detection system 33 are the same as those described with reference to FIG. The measurement light 11 irradiated from the TTM detection system 37 and the TTM detection system 38 is reflected by the mirror 39 and the mirror 40, passes through the relay optical system 34, and irradiates the mold 5 and the wafer 8. Reflected light from the alignment mark formed on the mold 5 and the alignment mark formed on the wafer 8 passes through the relay optical system 34, the TTM detection system 37, and the TTM detection system 38 and is detected by the light receiving element 46 for the TTM detection system. The The mold 5 and the wafer 8 can be aligned based on the detection signal.

  The mirror 39 and the mirror 40 are disposed in the vicinity of the image plane 47, and the reflected light can be bent and extracted. By arranging a mirror in the vicinity of the imaging plane 47, the light beam can be bent (reflected) before the effective diameter of the light beam expands, so that a plurality of TTM detection systems can be easily arranged.

  In the description of FIG. 5B, the mirror 39 and the mirror 40 are disposed after the imaging surface 47, but the mirror may be disposed before the imaging surface 47. As described above, by arranging the mirror on the imaging surface formed by the relay optical system or in the vicinity of the imaging surface, the height of the entire imprint apparatus can be suppressed, and the degree of freedom in design can be increased. Further, in the present embodiment, a part of the light beam is bent, but if it is desired to suppress the height of the apparatus, all the light beams may be bent and the detection system may be arranged in the lateral direction.

  FIG. 5C shows a schematic block diagram of an imprint apparatus 53 in which the mirror 39 and the mirror 40 are arranged in front of the image plane 47. The TTM detection system 37 and the TTM detection system 38 in FIG. 5C are characterized in that some light beams are bent by the mirror 39 and the mirror 40 before the relay optical system 34 forms the image plane 47. . As in FIG. 5B, since the light beam can be bent before the effective beam diameter increases, a plurality of TTM detection systems can be easily arranged.

  The relay optical system 34 can have the same configuration as the relay optical system described in the above embodiment. However, when the mirror is disposed and the reflected light is bent before forming the imaging surface 47 as shown in FIG. 5C, the imaging surface 47 is not necessarily formed. In such a case, after the light beam is bent by the mirror 39 and the mirror 40, the light reflected from the alignment mark forms an image. Therefore, the mirror 39 and the mirror 40 can be regarded as a part of the relay optical system. Here, this case is also referred to as “the relay optical system forms the image plane 47 of the wafer surface”.

  As described above, by using the method of configuring the relay optical system on the upper part of the mold, it is possible to alleviate the congestion on the arrangement on the mold and arrange a plurality of TTM detection systems having sufficiently large NA. As a result, even when a plurality of alignment marks are detected simultaneously, a sufficient amount of light of the TTM detection system can be ensured, and highly accurate alignment can be realized.

[Sixth Embodiment]
A sixth embodiment will be described with reference to FIG.

  In the description of FIGS. 5A to 5C, the illumination system 35 is disposed to be inclined with respect to the optical axis of the TTM detection system for the sake of simplicity. However, even when a plurality of TTM detection systems are arranged on the upper portion of the mold 5, illumination light from the illumination system may be incident on the wafer perpendicularly.

  FIG. 6 is a schematic block diagram of an imprint apparatus 41 that includes a plurality of TTM detection systems according to the sixth embodiment and causes illumination light from the illumination system to enter the wafer perpendicularly. As shown in FIG. 6, the imprint apparatus 41 of the sixth embodiment includes a wafer stage 9 that holds a wafer 8, an imprint head 4 that holds a mold 5, a resin coating mechanism 6, and a control unit 10. Up to this point, the configuration is the same as that of the imprint apparatus described in the above embodiment. The imprint apparatus 41 includes TTM detection systems 32, 33, 37, and 38 as in FIG.

  FIG. 6A shows the imprint apparatus 41 during alignment. At the time of alignment, the measurement light 11 irradiated from the TTM detection system passes through the relay optical system lens 49 formed in the relay optical system 34 and irradiates the mold 5 and the wafer 8. Reflected light from the alignment mark formed on the mold 5 and the alignment mark formed on the wafer 8 passes through the relay optical system 34 and the TTM detection system and is detected by the light receiving element 46 for the TTM detection system. The mold 5 and the wafer 8 can be aligned based on the detection signal. Thus, the optical path of the measurement light 11 at the time of alignment is not different from that in FIG.

  The relay optical system 34 can have the same configuration as the relay optical system described in the above embodiment. The screen size of the relay optical system (region of the wafer surface to be imaged) can be determined by determining the screen size of the relay optical system so that at least a plurality of alignment marks formed on the substrate are imaged simultaneously. Good.

  Although the mirror 39 and the mirror 40 for bending the measurement light 11 and the reflected light are arranged after the image forming surface 47 of the relay optical system, they may be arranged before the image forming surface 47 as in the fifth embodiment. However, it may be arranged on the image plane 47. As described above, by arranging the mirror in the vicinity of the imaging plane, the light beam can be bent before the effective diameter of the light beam is expanded, so that a plurality of TTM detection systems can be easily arranged.

  The illumination system 42 of the imprint apparatus 41 of the sixth embodiment is disposed on the mold 5. When the wafer 8 is illuminated, a mirror 43 for the illumination system 42 is disposed in the relay optical system 34 as shown in FIG. The illumination light 3 irradiated from the illumination system 42 passes through the illumination system lens 48, is bent by the bending mirror 51, and is guided to the mirror 43 disposed in the relay optical system 34. The illumination light 3 reflected by the mirror 43 passes through the mold 5 and irradiates the imprint resin supplied to the wafer 8. The imprint resin is cured when irradiated with the illumination light 3.

  FIG. 6C is a view showing an imprint apparatus 41 in which a plurality of TTM detection systems and illumination systems 42 are combined into one unit 44 and arranged on the upper part of the mold 5. If the method of configuring the relay optical system 34 on the mold as in the sixth embodiment is used, a large unit such as the TTM detection systems 32, 33, 37, and 38 and the unit 44 of the illumination system 42 are collectively molded. It is also possible to arrange it at the top of 5. By configuring the relay optical system 34 on the upper part of the mold 5, it is possible to arrange a large unit 44 as shown in FIG. 6C on the upper part of the mold 5, and a TTM detection system having a sufficiently large NA. Can be used to achieve highly accurate alignment.

  In the sixth embodiment, the mold 5 and the wafer 8 can be selectively irradiated with the measurement light 11 and the illumination light 3 by inserting and removing the mirror 43 into and from the relay optical system 34. Here, the optical member is not limited to the mirror 43 and may be any optical member that separates illumination light and measurement light. For example, the beam splitter described in FIGS. 1 and 2 may be used. If a beam splitter is used, a drive mechanism (not shown) for moving the mirror 43 is not required.

  The upper part of the mold 5 is very crowded in terms of arrangement, and conventionally only a TTM detection system having a small NA as shown in FIG. 9 can be arranged. The imprint apparatus according to any of the embodiments can arrange a TTM detection system having a large NA, and can realize highly accurate alignment. Therefore, in the imprint apparatus of the present invention, it is possible to correct the positional deviation generated between the mold 5 and the wafer 8 with high accuracy, and to superimpose the mold and the base pattern with high accuracy. In addition, it can contribute to the improvement of device yield.

  In any of the above embodiments, the TTM detection system has the light source and the alignment mark is irradiated with the measurement light. However, the TTM detection system may not necessarily have the light source. You may have the light source (measurement light illumination part) for irradiating measurement light to an alignment mark separately from a TTM detection system. The alignment mark may be irradiated with the light emitted from the measurement light illumination unit, and the light reflected from the alignment mark may be guided to the light receiving element by the TTM detection system.

  In any of the above embodiments, the relay optical system is described as imaging the entire shot surface. However, the relay optical system does not necessarily have to be the entire shot surface, and a plurality of marks may be guided to the detection system at the same time. Further, a relay optical system that forms an image of a plurality of shot regions may be used.

[Device manufacturing method]
A device (semiconductor integrated circuit element, liquid crystal display element, etc.) manufacturing method includes a step of forming a pattern on a substrate (wafer, glass plate, film-like substrate) using the above-described imprint apparatus. Further, the device manufacturing method may include a step of etching the substrate on which the pattern is formed. In addition, the manufacturing method in the case of manufacturing other articles, such as a patterned medium (recording medium) and an optical element, may include other processes for processing a substrate on which a pattern is formed instead of etching. The article manufacturing method of this embodiment is advantageous in at least one of the performance, quality, productivity, and production cost of the article as compared with the conventional method.

3 Irradiation light 5 Mold
8 Wafer (substrate)
DESCRIPTION OF SYMBOLS 10 Control part 11 Measurement light 19 TTM detection system 21 Imprint apparatus 22 Beam splitter (optical member)
23 Relay optical system 24 Illumination system 46 Light receiving element

Claims (19)

An imprint apparatus for forming a pattern of an imprint material on a substrate using a mold,
A light receiving element;
An imaging optical system for forming an image of the surface of the substrate on an imaging plane ;
A detection optical system that guides light from the mark formed on the substrate and the mark formed on the mold through the imaging optical system to the light receiving element;
Means for moving the detection optical system along the imaging plane;
An imprint apparatus characterized in that light from a mark formed on the substrate and a mark formed on the mold is detected by the light receiving element, and the substrate and the mold are aligned based on the detection result. . An imprint apparatus for forming a pattern of an imprint material on a substrate using a mold,
A light receiving element;
An imaging optical system for forming an image of the surface of the substrate on an imaging plane ;
A detection optical system that guides light from the mark formed on the substrate and the mark formed on the mold to the light receiving element through the imaging optical system;
The imaging optical system, the light from the first type marks formed on the first substrate mark and the type formed in the substrate, which is formed in the mold and the second substrate mark formed on the substrate The light from the second type mark is incident on the imaging plane ;
A plurality of sets of the light receiving element and the detection optical system are provided,
The light from the first substrate mark and the first type mark is guided to the first light-receiving element by the first set of detection optical systems, and the second set of the plurality of sets is guided. The light from the second substrate mark and the second type mark is guided to the second set of light receiving elements by a detection optical system,
Light from the first substrate mark and the first type mark is detected by the first set of light receiving elements, and light from the second substrate mark and the second type mark is detected by the second set of light receiving elements. The imprint apparatus is characterized in that the substrate and the mold are aligned based on the results detected by the first set of light receiving elements and the second set of light receiving elements. Wherein there focal plane between the detection optical system and the imaging optical system, means for moving the second set of detection optical system and the first set of the detection optical system along the imaging plane The imprint apparatus according to claim 2, further comprising: Wherein the size of the region on the surface of the substrate to be imaged by the imaging optical system, wherein at least the size of the region of the mold the formed pattern imaged by the imaging optical system The imprint apparatus according to any one of claims 1 to 3. An imprint apparatus for forming a pattern of an imprint material on a substrate using a mold,
A light receiving element;
An imaging optical system for forming an image of the surface of the substrate on an imaging plane ;
A detection optical system that guides light from the mark formed on the substrate and the mark formed on the mold through the imaging optical system to the light receiving element;
An illumination system for supplying illumination light for curing the imprint material,
The imaging optical system transmits one of light from a mark formed on the substrate, a mark formed on the mold, and illumination light for curing the imprint material, and reflects the other light. An optical member
Means for moving the detection optical system along the imaging plane, and the light from the mark formed on the substrate and the mark formed on the mold is detected by the light receiving element; An imprint apparatus characterized in that the substrate and the mold are aligned. An imprint apparatus for forming a pattern of an imprint material on a substrate using a mold,
A light receiving element;
An imaging optical system for forming an image of the surface of the substrate on an imaging plane ;
A detection optical system that guides light from the mark formed on the substrate and the mark formed on the mold to the light receiving element through the imaging optical system;
The imaging optical system transmits one of light from a mark formed on the substrate, a mark formed on the mold, and illumination light for curing the imprint material, and reflects the other light. An optical member
The imaging optical system, the light from the first type marks formed on the first substrate mark and the type formed in the substrate, which is formed in the mold and the second substrate mark formed on the substrate The light from the second type mark is incident on the imaging plane ;
A plurality of sets of the light receiving element and the detection optical system are provided,
The light from the first substrate mark and the first type mark is guided to the first light-receiving element by the first set of detection optical systems, and the second set of the plurality of sets is guided. The light from the second substrate mark and the second type mark is guided to the second set of light receiving elements by a detection optical system,
Light from the first substrate mark and the first type mark is detected by the first set of light receiving elements, and light from the second substrate mark and the second type mark is detected by the second set of light receiving elements. The imprint apparatus is characterized in that the substrate and the mold are aligned based on the results detected by the first set of light receiving elements and the second set of light receiving elements. 7. The imprint apparatus according to claim 6, further comprising means for moving the first set of detection optical systems and the second set of detection optical systems along the imaging plane. Wherein the size of the region on the surface of the substrate to be imaged by the imaging optical system, wherein at least the size of the region of the mold the formed pattern imaged by the imaging optical system The imprint apparatus according to any one of claims 5 to 7. The detection optical system irradiates the mark light formed in the mold and the mark formed on the substrate from a light source,
The imprint apparatus according to any one of claims 5 to 8, wherein the imprint material is cured by the illumination light having a wavelength different from a wavelength of light from the light source.   The imprint apparatus according to claim 9, wherein the illumination light is ultraviolet light, and light from the light source is visible light or infrared light.   The said optical member reflects the said illumination light, and permeate | transmits the light from the mark formed in the said board | substrate, and the mark formed in the said type | mold. Imprint device.   The said optical member permeate | transmits the said illumination light, and reflects the light from the mark formed in the said board | substrate, and the mark formed in the said type | mold, It is any one of Claims 5-10 characterized by the above-mentioned. Imprint device. An illumination system for supplying illumination light for curing the imprint material;
The imprint apparatus according to claim 1, wherein the illumination light passes through the imaging optical system and irradiates the imprint material. A switching mechanism for switching the arrangement of the detection optical system and the illumination system, the switching mechanism,
When detecting light from the mark formed on the substrate and the mark formed on the mold, the detection optical system is arranged so that light from the imaging optical system is guided to the light receiving element, The imprint apparatus according to claim 13, wherein when the imprint material is cured, the illumination system is arranged so that the illumination light illuminates the substrate through the imaging optical system. An illumination system for supplying illumination light for curing the imprint material;
A mirror that reflects the illumination light and irradiates the imprint material;
A drive mechanism for moving the mirror,
5. The imprint according to claim 1, wherein when the imprint material is cured, the drive mechanism moves the mirror and arranges the imprint material in the imaging optical system. apparatus. Wherein the size of the region on the surface of the substrate to be imaged by the imaging optical system is more than the size of the irradiation region of the illumination light on the substrate formed by the imaging optical system The imprint apparatus according to any one of claims 5 to 15. The imprint apparatus according to claim 1, wherein the imaging optical system is a telecentric optical system. The detection optical system is characterized in that an optical path of light from a mark formed on the substrate and a mark formed on the mold is bent by an image forming surface on the surface of the substrate or a mirror near the image forming surface. The imprint apparatus as described in any one of Claims 1-17. A step for aligning the mold and the substrate by using the imprint apparatus according to any one of claims 1 to 18,
Close together the mold and the substrate, a step of Ru contacting the mold with imprint material on the substrate,
Forming a pattern of the imprint material to the substrate by releasing by curing the imprint material in a state in which the imprint material and the mold is in contact and the alignment is performed, in the step Processing the substrate on which the pattern is formed;
A device manufacturing method comprising:

Images