JP6271831B2 - Exposure apparatus and device manufacturing method using the same - Google Patents

Description

  The present invention relates to an exposure apparatus and a device manufacturing method using the exposure apparatus.

  In a lithography process included in a manufacturing process of a semiconductor device, a liquid crystal display device, or the like, an exposure apparatus applies a pattern of an original (such as a reticle) to a photosensitive substrate (a wafer having a resist layer formed on the surface) via a projection optical system. It is a device that transfers to a glass plate or the like. The exposure apparatus includes an alignment detection system (position detection system) for performing relative alignment between the original and the substrate. As an alignment detection system, for example, there is an off-axis alignment detection system (OA detection system) that is adjacent to the projection optical system and detects a mark on the substrate or stage (substrate holding unit) without using the projection optical system. . This OA detection system has an advantage that it is not affected by the chromatic aberration of the projection optical system, as compared with the detection system via the projection optical system. Patent Document 1 discloses a position detection device that is such an OA detection system. Conventionally, an exposure apparatus detects marks using a single OA detection system. However, since the number of marks on the substrate has increased with the recent increase in the diameter of the substrate, detection of these marks has been performed as one. Implementation with one OA detection system takes time and reduces throughput. Therefore, Patent Document 2 discloses an exposure apparatus including a plurality of OA detection systems in order to shorten the mark detection time.

JP 2004-279166 A Japanese Patent Laying-Open No. 2005-116777

  Here, the baseline amount, which is the distance between the optical axis of the projection optical system and the optical axis of the OA detection system, may fluctuate due to the influence of expansion / contraction of the apparatus material due to exposure heat when the exposure apparatus is used. is there. When the baseline amount fluctuates, the detection accuracy of the OA detection system, and thus the overlay accuracy, may exceed the allowable range. Therefore, in order to maintain the detection accuracy of the OA detection system, it is necessary to periodically measure the baseline, and to correct the baseline amount if it has fluctuated. However, if baseline measurement is performed regularly, the measurement time may accumulate, which may affect throughput. In particular, in an exposure apparatus provided with a plurality of OA detection systems shown in Patent Document 2, the position variation of at least one movable second OA detection system is larger than that of the fixed first OA detection system. Therefore, it is necessary to frequently measure (specify) the position of the second OA detection system.

  For example, assume an exposure apparatus that includes two position detection systems, a first OA detection system (fixed) and a second OA detection system (movable). And the position where the stage exchanges the collection substrate and the supply substrate by its own movement is defined as the “exchange position”. On the other hand, the movement of the stage can avoid interference between the chuck of the stage and the hand (conveyance mechanism). Is defined as an “avoidance position”. Here, when supplying the supply substrate, the hand first receives the supply substrate from the supply position and then moves to the replacement position. At this time, the stage stands by at the replacement position with the chuck lowered. Next, the hand descends to deliver the supply wafer to the pins. Next, the hand is retracted in the − (minus) direction of a certain axial direction, and the stage moves in the + direction in accordance with the retraction. This is to avoid interference between the chuck and the hand when the chuck is raised and the supply substrate is sucked and held on the chuck. Next, the stage moves in the + direction as described above and temporarily stops at the avoidance position. Then, when the chuck is raised, the supply substrate is transferred from the pin to the chuck and is held by suction. Next, when performing baseline measurement, the stage moves from the avoidance position to a position (measurement position) where at least one of the marks on the stage enters the observation area of the second OA detection system. This movement is for frequently measuring the baseline of the second OA detection system in order to prevent the movement error of the second OA detection system itself from becoming a measurement value error of the baseline amount. That is, in the conventional exposure apparatus, the stage moves between the first movement from the replacement position to the avoidance position and the second movement from the avoidance position to the measurement position before receiving the supply substrate from the hand and reaching the baseline measurement. Two moves will be performed. Since the first movement and the second movement are required, the time required for the baseline measurement becomes long, and as a result, the throughput can be affected.

  The present invention has been made in view of such a situation, and an object of the present invention is to provide an exposure apparatus that is advantageous for improving throughput, for example.

In order to solve the above problems, the present invention is an exposure apparatus that irradiates a pattern formed on an original plate with light from an illumination system and projects an image of the pattern onto a substrate via a projection optical system. A substrate holding unit that has a suction unit that sucks the substrate, a plurality of pins for transferring the substrate, a lifting mechanism that relatively moves the suction unit up and down, and a first mark, and is movable by sucking the substrate by the suction unit And a detection system that detects the first mark or the second mark formed on the substrate without using the projection optical system, and a transport mechanism that transfers the substrate to the pins to a plurality of substrate holding portions, With respect to the horizontal position, the first position where the substrate holding unit is located when the transport mechanism passes the substrate to the plurality of pins, and the substrate passed to the plurality of pins from the transport mechanism is sucked to the suction portion using the lifting mechanism. The second position where the substrate holder is located The substrate holder is moved in the first direction as the transport mechanism moves between the substrate and the suction portion so as to move away from the substrate holder in the horizontal direction after the transport mechanism passes the substrate to the plurality of pins. The detection system detects the first mark of the substrate holder that has moved from the first position to the second position and has moved to the second position.

  According to the present invention, for example, it is possible to provide an exposure apparatus that is advantageous for improving the throughput.

It is a figure which shows the structure of the exposure apparatus which concerns on 1st Embodiment of this invention. It is a figure which shows the structure of a position detection system. It is a figure explaining baseline measurement. It is a figure explaining the alignment measurement of a wafer. It is a figure which shows the exchange operation | movement of the wafer in 1st Embodiment. It is a figure which shows the exchange operation | movement of the wafer in 2nd Embodiment. It is a figure which shows the exchange operation | movement of the wafer in the conventional exposure apparatus.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

(First embodiment)
First, the configuration of the exposure apparatus according to the first embodiment of the present invention will be described. FIG. 1 is a schematic view showing the configuration of the exposure apparatus 1 of the present embodiment. As an example, the exposure apparatus 1 is used in a semiconductor device manufacturing process, and a pattern (for example, a circuit pattern) formed on a reticle (original) 2 by a step-and-repeat method is a wafer 3 that is a substrate to be processed. A projection exposure apparatus that performs transfer exposure on the top (on the substrate) is used. In FIG. 1, the Z axis is parallel to the optical axis of the projection optical system 4 (vertical direction in the present embodiment), and X in the scanning direction of the reticle 2 and the wafer 3 during exposure in a plane perpendicular to the Z axis. The axis is taken, and the Y axis is taken in the non-scanning direction orthogonal to the X axis. The exposure apparatus 1 includes an illumination system 5, a reticle stage 6, a projection optical system 4, a wafer stage 7, a position detection system 8, and a control unit 9.

  The illumination system 5 includes, for example, an optical element such as a lens, a mirror, a light integrator, or a diaphragm, and illuminates the reticle 2 by adjusting light emitted from a light source (not shown). As the light source, for example, a pulse laser light source can be adopted. Here, when a laser is used as the light source, the illumination system 5 is a shaping optical system that shapes the parallel light flux from the laser light source into a desired beam shape, or an incoherent optical that makes the coherent laser light incoherent. It is desirable to include a system. On the other hand, the light source is not limited to a laser light source, and may be one or a plurality of mercury lamps or xenon lamps. The reticle 2 is an original plate made of, for example, quartz glass, on which a pattern to be transferred is formed on the wafer 3. The reticle stage (original plate holding unit) 6 holds the reticle 2 and is movable in the XY axis directions. Further, the reticle stage 6 has a reference mirror 11, and the position of the reticle stage 6 is measured by a first laser interferometer 12 that irradiates the reference mirror 11 with a laser beam and receives the reflected light. The projection optical system 4 projects and exposes the pattern on the reticle 2 illuminated with the irradiation light 10 from the illumination system 5 onto the wafer 3 at a predetermined magnification (for example, 1/2 to 1/5). As the projection optical system 4, an optical system composed only of a plurality of optical elements or an optical system composed of a plurality of lenses and at least one concave mirror (catadioptric optical system) can be employed. Alternatively, as the projection optical system 4, an optical system including a plurality of lenses and at least one diffractive optical element such as a kinoform, an optical system including a plurality of mirrors, and the like can be employed. The wafer 3 is a substrate made of single crystal silicon, for example, having a resist (photosensitive agent) coated on the surface thereof. A wafer stage (substrate holding unit) 7 holds the wafer 3 and is movable in at least the X-axis direction and the Y-axis direction. The wafer stage 7 has a chuck (suction part) 13 that attracts and holds the wafer 3 by suction force, and the chuck 13 or a plurality of pins that temporarily suction and support the wafer 3 in the Z-axis direction. And an elevating mechanism that allows the wafer 3 to be separated from the surface of the chuck 13. In particular, the elevating mechanism of this embodiment is not shown, but the elevating drive unit for elevating the chuck 13 on the wafer stage 7 and the position itself are fixed, and the wafer is temporarily moved when the chuck 13 is lowered. 3 and a plurality of pins 14 supporting 3. Further, the wafer stage 7 has a reference mirror 15, and the position of the wafer stage 7 is measured by a second laser interferometer 16 that irradiates the reference mirror 15 with a laser beam and receives the reflected light. The exposure apparatus 1 may include a laser interferometer that measures the position of the wafer stage 7 in the Z-axis direction.

The position detection system 8 uses an alignment mark (second mark: hereinafter referred to as “wafer mark”) formed on the wafer 3 or a reference mark (first mark) placed on the wafer stage 7 as alignment processing. Can be detected. In particular, in the present embodiment, an off-axis auto alignment detection system (OA detection system) that detects each mark without using the projection optical system 4 is employed as the position detection system 8. In addition, the exposure apparatus 1 includes a plurality of such position detection systems 8, and particularly in this embodiment, two position detection systems (first position detection system 8a and second position detection system 8b: see FIGS. 4 and 5). ). Each position detection system 8a, 8b is provided adjacent to the projection optical system 4, and each optical axis is parallel to the optical axis of the projection optical system 4. Further, each position detection system 8a, 8b has the same basic configuration, but one is fixed without a driving mechanism at the arrangement position adjacent to the projection optical system 4, and the other is It has a drive mechanism, and makes the observation region (detection region) variable within a specific range in each of the X, Y, and Z axial directions, for example. In the following description, it is assumed that the first position detection system 8a does not have a drive mechanism, and the second position detection system 8b has a drive mechanism. This drive mechanism may change the entire position of the second position detection system 8b or may change a part of the position.

  FIG. 2 is a diagram illustrating an example of a basic configuration of the position detection system 8. The position detection system 8 first includes a first light source 20 and an optical system related to illumination and imaging. The first light source 20 emits, for example, visible light (or infrared light), and the emitted light passes through the two illumination relay optical systems 21 and 22 and is an aperture stop formed on the rotating plate 23. To form an image. The specific light that has passed through the aperture stop further passes through the illumination optical system 24 and then enters the polarization beam splitter 25. The S-polarized light reflected by the polarization beam splitter 25 passes through the relay lens 26 and the λ / 4 plate 27, is converted to circularly polarized light, and further passes through the objective lens 28 to form a wafer mark formed on the wafer 3. Koehler illuminates the WM. Next, the reflected light, diffracted light, and scattered light generated at the wafer mark WM return to the objective lens 28, the λ / 4 plate 27, and the relay lens 26. These lights are then converted into P-polarized light, and then pass through the polarization beam splitter 25, and an image of the wafer mark WM is formed on the photoelectric conversion element (for example, CCD camera) 30 by the imaging optical system 29. The control unit 9 specifies the position of the wafer 3 based on the position of the image of the wafer mark WM acquired from the photoelectric conversion element 30. On the other hand, the position detection system 8 further includes a second light source 31 and an optical system related to the reference illumination. The light emitted from the second light source is Koehler illuminated by the illumination optical system 32 so as to have a uniform light amount distribution with respect to the reference plate 33. Here, the reference plate 33 has a reference mark SM, and only light transmitted through the reference mark SM enters the half mirror 34. By using the first light source 20 that emits alignment light and the second light source 31 that emits reference light as separate light sources, the second light source 31 is used when the wafer mark WM is illuminated by the use of the first light source 20. Does not emit reference light. On the other hand, when the reference mark SM is illuminated by using the second light source 31, the first light source 20 does not emit alignment light. Thereby, the position detection system 8 can form the wafer mark WM and the reference mark SM in the same visual field. Then, the control unit 9 calculates the position of the wafer mark WM with respect to the reference mark SM based on the detection result.

  The control unit 9 can control the operation and adjustment of each component of the exposure apparatus 1. The control unit 9 is composed of, for example, a computer and is connected to each component of the exposure apparatus 1 via a line, and can control each component according to a program or the like. The control unit 9 according to the present embodiment is based on at least the drive control of the wafer stage 7 during the transfer of the wafer 3 and the baseline measurement described later, the operation control of the position detection system 8, or the detection result of the position detection system 8. Execute line amount calculation. The control unit 9 may be configured integrally with other parts of the exposure apparatus 1 (in a common housing) or separate from the other parts of the exposure apparatus 1 (in a separate housing). It may be configured.

  Next, the exchange operation of the wafer 3 until the baseline measurement, the alignment measurement, and the baseline measurement, which are operations related to the alignment processing in the exposure apparatus 1, will be described. In general, an exposure apparatus performs an alignment process for aligning a shot (pattern transfer area) on a wafer with an exposure area (a projected image of a reticle pattern) of the exposure apparatus before performing the exposure process. Furthermore, when an OA detection system is employed as the position detection system for performing this alignment process, it is necessary to obtain the baseline amount in advance with high accuracy. Here, the baseline amount is an offset amount of a reference point (for example, the center point) of the observation region of the position detection system with respect to a reference point (for example, the center point) in the exposure region, that is, a distance between the two reference points. is there. Prior to describing the alignment processing in the exposure apparatus 1 of the present embodiment, first, baseline measurement necessary for the alignment processing of the wafer 3 will be described.

  FIG. 3 is a schematic diagram showing the main configuration and operation of the exposure apparatus 1 for explaining the baseline measurement. 3A is a plan view of the reticle stage 6 viewed from the incident side of the irradiation light 10, and FIG. 3B shows a main configuration of the exposure apparatus 1 corresponding to FIG. 3A. It is a side view. Here, the reticle stage 6 is provided with a plurality of reticle reference marks 40 for aligning the positions of the reticle 2 and the reticle stage 6 and two reticle stage reference plates 41 on the surface thereof. A plurality of position measurement marks (third marks: hereinafter referred to as “RS marks”) 42 are arranged on the reticle stage reference plate 41 at predetermined intervals. Further, the wafer stage 7 has a wafer stage reference mark 43 placed on the chuck 13. Although not shown, the wafer stage reference mark 43 has a plurality of position measurement marks (hereinafter referred to as “WS marks”) arranged at predetermined intervals. Hereinafter, for the sake of simplicity of explanation, the WS mark is also given the same reference numeral as the wafer stage reference mark. Prior to baseline measurement, the control unit 9 first detects the reticle reference mark 40 using a reticle alignment microscope (not shown), and positions the reticle 2 relative to the reticle stage 6. Next, as a first step of baseline measurement, the control unit 9 determines the relative position between the RS mark 42 and the WS mark 43 via the projection optical system 4 by an alignment scope (exposure light scope) 44 using exposure light. Let it be detected. At this time, the chuck 13 is stopped at a fixed position when it is raised (hereinafter referred to as “lifted position”). In this raised position, the height positions in the Z-axis direction of the surface of the wafer 3 held by the chuck 13 and the surface of the wafer stage reference mark 43 are substantially the same. Next, after the completion of the first step, the controller 9 moves the wafer stage 7 to align the WS mark 43 with the observation region (field of view) of the position detection system 8 as the second step. Thereafter, the control unit 9 detects the relative position between the WS mark 43 and the reference mark SM in the position detection system 8. And the control part 9 calculates a baseline amount by taking the difference of position information based on the detection result of a 1st process and a 2nd process. Thereby, when the alignment measurement with respect to the wafer 3 is performed using the position detection system 8, the shot on the wafer 3 can be matched with the exposure region of the exposure apparatus 1. Note that after the baseline amount is specified, the position of the wafer mark WM (see FIG. 2) can be detected using the reference mark SM as a reference.

  In particular, since the position detection system 8 of the present embodiment is the fixed first position detection system 8a and the movable second position detection system 8b, the measurement positions of the baseline are the following three locations: Become. The first measurement position is a position obtained by aligning the WS mark 43 on the XY plane by driving the drive mechanism immediately below the installation position of the second position detection system 8b. At this measurement position, the second position detection system 8b detects the WS mark 43. The second measurement position is a position where the WS mark 43 is aligned on the XY plane by driving the wafer stage 7 immediately below the installation position of the first position detection system 8a. At this measurement position, the first position detection system 8a detects the WS mark 43. The third measurement position is a position obtained by aligning the WS mark 43 on the XY plane by driving the wafer stage 7 immediately below the installation position of the exposure light scope 44 (see FIG. 3) via the projection optical system 4. is there. At this measurement position, the exposure light scope 44 detects the relative position between the RS mark 42 (see FIG. 3) and the WS mark 43. In the above, it is described that the control unit 9 takes the difference in the position information based on the detection results of the first process and the second process. Specifically, the difference between the measurement results at these three measurement positions. Means to take. In the detection at the second and third measurement positions, since the detected value is often relatively stable, the detection is performed once for each of a plurality of wafers 3 instead of for each wafer 3. Implementation is also possible.

  FIG. 4 is a schematic plan view of the wafer 3 for explaining alignment measurement by the position detection system 8. A plurality of shots S are set on the wafer 3, and a plurality of wafer marks WM are formed on the plurality of shots S. Here, as an example, only four shots and wafer marks are shown. The interval L between the wafer marks WM is set in advance based on the arrangement of the marks on the reticle 2 and the shot layout on the wafer 3. The exposure apparatus 1 performs the above-described baseline measurement, and then performs alignment measurement by the position detection system 8 during the exposure process. At this time, since the exposure apparatus 1 includes the two position detection systems 8 of the first position detection system 8a and the second position detection system 8b, as shown in FIG. That is, at least a part of the detection timing can be overlapped for detection. In particular, the position of the formed wafer mark WM differs depending on the wafer 3. In this case, the control unit 9 first adjusts the observation position of the first position detection system 8 a to one wafer mark WM by moving the wafer stage 7. Thereafter, the control unit 9 moves the second position detection system 8b to a position set in advance based on the arrangement of the marks on the reticle 2 and the shot layout on the wafer 3, thereby observing the observation position of the second detection system 8b. Is adjusted to match another wafer mark WM. The driving of the second position detection system 8b is fixed before the baseline measurement. Such simultaneous alignment measurement for a plurality of wafer marks WM can shorten the drive time of the wafer stage 7 as compared with the case where there is one position detection system, and is consequently required for alignment measurement. Time is shortened.

  Here, before the baseline measurement as described above is performed, the wafer to be exposed from now on must be placed (transferred) at the baseline measurement position. Then, next, the exchange operation | movement of the wafer 3 by the exposure apparatus 1 including the conveyance operation of the wafer 3 by the wafer stage 7 is demonstrated. First, before the description of this embodiment, the operation of a conventional exposure apparatus will be described for comparison. In the following description of the conventional exposure apparatus, the same reference numerals are assigned to the same components as those of the exposure apparatus 1 of the present embodiment for ease of comparison.

  FIG. 7 is a schematic diagram for explaining the exchange (delivery) operation of the wafer 3 by the conventional exposure apparatus. In FIG. 7, a state in which a wafer (hereinafter referred to as “supply wafer”) 3 a to be exposed from now on is placed on the chuck 13 of the wafer stage 7 and conveyed to the baseline measurement position is shown in time series. . FIG. 7 schematically shows the installation positions of the projection optical system 4 and the first position detection system 8 a and the second position detection system 8 b provided adjacent to the projection optical system 4. Although not shown, a supply stage that temporarily holds the supply wafer 3a in the exposure apparatus 1 or adjacent to the exposure apparatus 1 and a processed wafer (hereinafter referred to as “recovered wafer”) 3b are provided. A collection stage for temporary holding is installed. Hereinafter, the position where the supply stage temporarily holds the supply wafer 3 a is referred to as “supply position”. On the other hand, a position where the collection stage temporarily stores the collection wafer 3b is referred to as a “collection position”. Further, the exposure apparatus 1 includes a hand 50 that holds and transfers the wafer 3 between an exchange position, which will be described later, and the supply position and the collection position. The hand 50 is moved by a driving unit (not shown) and constitutes a transport mechanism together with the driving unit.

  FIG. 7A is a diagram showing a state in which the wafer stage 7 is located at a position (first position: hereinafter referred to as “exchange position”) where the recovery wafer 3b and the supply wafer 3a are exchanged by their movement. is there. Here, when recovering the recovery wafer 3b, first, the wafer stage 7 holding the recovery wafer 3b is moved to the replacement position and temporarily stopped. Next, the suction holding of the collection wafer 3b is released, and the chuck 13 is lowered at this replacement position, whereby the collection wafer 3b is supported on the pins 14. Next, the hand 50 enters the gap space between the collection wafer 3b supported by the pins 14 and the lowering chuck 13 from the horizontal direction, and then moves up to receive the collection wafer 3b from the pins 14. . Then, the hand 50 conveys the collection wafer 3b to the collection position. Here, the position of the wafer stage 7 is the same when exchanging the recovery wafer and the supply wafer. However, the wafer stage position for recovering the recovery wafer is different from the wafer stage position for supplying the supply wafer. May be.

  FIG. 7B shows a state in which the wafer stage 7 is located at a position where the interference between the chuck 13 and the hand 50 can be avoided by its own movement (second position: hereinafter referred to as “avoided position”). FIG. Here, when supplying the supply wafer 3a, first, the hand 50 receives the supply wafer 3a from the supply position and then moves to the replacement position. At this time, the wafer stage 7 stands by at the replacement position with the chuck 13 lowered. Next, the hand 50 moves down to deliver the supply wafer 3 a to the pins 14. Next, the hand 50 is retracted in the −Y axis direction, and the wafer stage 7 moves in the + Y axis direction in accordance with the retract. This is to avoid interference between the chuck 13 and the hand 50 when the chuck 13 is raised and the supply wafer 3 a is sucked and held on the chuck 13. It is also conceivable to avoid interference with the chuck 13 by largely retracting only the hand 50 while the wafer stage 7 is stopped at the replacement position. However, this operation is not desirable from the viewpoint of taking time compared to the case where both of the hands 50 move and the space saving in the apparatus. Next, the wafer stage 7 moves in the + Y-axis direction as described above, and temporarily stops at the avoidance position. Here, the movement of the wafer stage 7 from the replacement position to the avoidance position is defined as “first movement”. Then, as the chuck 13 moves up, the supply wafer 3a is transferred from the pin 14 to the chuck 13 and sucked and held. The stop of the wafer stage 7 here is indispensable so that the position of the supply wafer 3a does not shift with respect to the wafer stage 7 at the time of wafer delivery. Next, when performing baseline measurement, the wafer stage 7 moves from the avoidance position to a position where at least one of the WS marks 43 enters the observation region of the second position detection system 8b (hereinafter referred to as “measurement position”). This movement is to frequently measure the baseline of the second position detection system 8b in order to prevent the movement error of the second position detection system 8b itself from becoming a measurement value error of the baseline amount. Here, the movement of the wafer stage 7 from the avoidance position to the measurement position is defined as “second movement”. That is, in the conventional exposure apparatus, the wafer stage 7 performs two movements of the first movement and the second movement until the supply wafer 3a is received from the hand 50 and the baseline measurement is performed.

  On the other hand, the exchange operation of the wafer 3 by the exposure apparatus 1 according to this embodiment is different from the operation by the conventional exposure apparatus described with reference to FIG. FIG. 5 is a schematic diagram for explaining the exchange operation of the wafer 3 by the exposure apparatus 1 corresponding to FIG. In particular, in the present embodiment, as shown in FIG. 5B, the avoidance position is the same as the measurement position. At this time, the size of the WS mark 43 is set in advance larger than the driving amount of the second position detection system 8b (that is, the variable range of the observation region), and the WS mark 43 is always directly below the second position detection system 8b at the avoidance position. It is desirable to make the mark 43 easy to enter. That is, in the exposure apparatus 1, the wafer stage 7 does not need the second movement that has been necessary in the past when the wafer 3 is exchanged, and only performs the first operation. Therefore, the exposure apparatus 1 can shorten the time for the second operation in the driving time of the wafer stage 7. Conventionally, exposure systems with multiple position detection systems have had an advantage in throughput compared to those with only one position detection system, but regularly perform baseline measurements to maintain detection accuracy. Had to affect the throughput. On the other hand, the exposure apparatus 1 can reduce the time required for the second operation as described above. As a result, the time required for the baseline measurement can be reduced and the throughput of the entire apparatus can be reduced. Can be suppressed as much as possible. Here, attention is paid to the operation of supplying the supply wafer 3a. However, focusing on the operation of recovering the recovery wafer 3b shown in FIG. 5A, the second position detection system 8b at the avoidance position at the time of wafer recovery. Baseline measurements may be performed. Further, when the WS mark 43 is removed from the observation area of the second position detection system 8b at the avoidance position, the control unit 9 drives the wafer stage 7 so that the WS mark 43 enters the observation area. The avoidance position may be changed slightly.

  As described above, according to the present embodiment, it is possible to provide an exposure apparatus that is advantageous for improving the throughput.

(Second Embodiment)
Next, an exposure apparatus according to the second embodiment of the present invention will be described. The feature of the exposure apparatus according to the present embodiment is that the wafer stage reference mark (WS mark) included in the wafer stage 7 is placed on the wafer stage 7 instead of being placed on the chuck 13 in the first embodiment. There is in point. FIG. 6 is a schematic diagram for explaining the exchange operation of the wafer 3 by the exposure apparatus according to the present embodiment, corresponding to FIG. 5 according to the first embodiment. In FIG. 6, the same components as those of the exposure apparatus 1 according to the first embodiment shown in FIG. In this case, the wafer stage reference mark 51 is installed such that the height position in the Z-axis direction between the surface of the wafer stage mark 51 and the surface of the wafer 3 held by the chuck 13 is substantially the same. Thereby, for example, as shown in FIG. 6B, the second position detection system 8b waits for completion of the ascending drive of the chuck 13 at the measurement position (synonymous with the avoidance position as in the first embodiment). Without detection, the WS mark 51 can be detected from the start of the ascending drive. Therefore, the exposure apparatus of the present embodiment not only shortens the time for the second operation of the wafer stage 7, but also can advance the detection start time by the second position detection system 8b, so that the baseline measurement can be performed. Such time can be further shortened.

  In each of the embodiments described above, for example, if a unit including the wafer stage 7, the position detection system 8, and the transfer mechanism (hand 50) is regarded as a positioning device, the positioning device is applied to the exposure apparatus. However, the positioning device can be applied not only to such an exposure apparatus, but also, for example, an in-position for forming a pattern on the substrate by curing the resin on the substrate in contact with the pattern portion of the mold. The present invention can be similarly applied to a lithography apparatus such as a printing apparatus.

(Device manufacturing method)
Next, a method for manufacturing a device (semiconductor device, liquid crystal display device, etc.) according to an embodiment of the present invention will be described. A semiconductor device is manufactured through a pre-process for producing an integrated circuit on a wafer and a post-process for completing an integrated circuit chip on the wafer produced in the pre-process as a product. The pre-process includes a step of exposing a wafer coated with a photosensitive agent using the above-described exposure apparatus, and a step of developing the wafer. The post-process includes an assembly process (dicing and bonding) and a packaging process (encapsulation). A liquid crystal display device is manufactured through a process of forming a transparent electrode. The step of forming the transparent electrode includes a step of applying a photosensitive agent to a glass substrate on which a transparent conductive film is deposited, a step of exposing the glass substrate on which the photosensitive agent is applied using the above-described exposure apparatus, and a glass substrate. The process of developing is included. According to the device manufacturing method of the present embodiment, it is possible to manufacture a higher quality device than before.

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

DESCRIPTION OF SYMBOLS 1 Exposure apparatus 2 Reticle 3 Wafer 4 Projection optical system 5 Illumination system 7 Wafer stage 8a 1st position detection system 8b 2nd position detection system 13 Chuck 43 Wafer stage reference mark 50 Hand WM Wafer mark

Claims (11)

An exposure apparatus that irradiates a pattern formed on an original plate with light from an illumination system and projects an image of the pattern onto a substrate via a projection optical system,
A suction part for sucking the substrate, a plurality of pins for transferring the substrate, and a lifting mechanism and a first mark for moving the suction part relative to each other, and a first mark for sucking and moving the substrate by the suction part Possible substrate holders,
A detection system for detecting the first mark or the second mark formed on the substrate without going through the projection optical system;
A transfer mechanism for delivering the substrate to the plurality of pins of the substrate holding unit,
With respect to the horizontal position, the substrate holding unit is positioned when the transport mechanism passes the substrate to the plurality of pins, and the substrate passed from the transport mechanism to the plurality of pins is moved up and down. Different from the second position where the substrate holding part is located when adsorbing to the adsorption part using a mechanism,
After the transport mechanism passes the substrate to the plurality of pins, the transport mechanism moves between the substrate and the suction unit so as to move away from the substrate holding unit with respect to the horizontal direction. The holding portion moves from the first position toward the second position;
An exposure apparatus, wherein the detection system detects the first mark of the substrate holding portion moved to the second position. The first mark is installed on the suction portion,
The elevating mechanism has a drive unit that raises the suction unit in a state where the substrate is supported by the plurality of pins.
When the substrate holding unit is in the second position, the detection system starts detecting the first mark after the substrate is adsorbed by the adsorbing unit raised by the driving unit. The exposure apparatus according to claim 1. The first mark is provided in a portion different from the suction portion of the substrate holding portion,
The elevating mechanism has a drive unit that raises the suction unit in a state where the substrate is supported by the plurality of pins.
When the substrate holding unit is in the second position, the detection system starts detecting the first mark before the substrate is adsorbed by the adsorbing unit raised by the driving unit. The exposure apparatus according to claim 1.   The exposure apparatus according to claim 1, wherein the detection system includes a drive mechanism that makes a detection region variable.   The detection system includes a plurality of detection systems, and the plurality of detection systems include a detection system in which a detection region is variable and a detection system in which the detection region is fixed. The exposure apparatus according to any one of the above.   The distance between the two detection systems is calculated based on the first mark detected by the detection system that fixes the detection area and the detection system that makes the detection area variable, and based on the distance value The two detection systems include a control unit that corrects a distance between the second marks when at least two of the second marks are detected while at least a part of detection timing overlaps. An exposure apparatus according to claim 5.   The exposure apparatus according to claim 6, wherein the control unit causes the detection system to detect the first mark for each of a plurality of the substrates set in advance. An original holding unit including a third mark, which is movable while holding the original; and
A scope capable of detecting a relative position between the first mark and the third mark via the projection optical system;
The control unit causes the scope and the previous detection system to measure a baseline amount between a reference point of an exposure area and a reference point of each detection area of the detection system, and uses the baseline amount as a reference Moving the substrate holder so that the pattern transfer region on the substrate matches the exposure region;
An exposure apparatus according to claim 6 or 7, wherein A suction part for sucking a substrate, a plurality of pins for transferring the substrate, a lifting mechanism for moving the suction part relative to each other, and a first mark are provided, and the suction part can suck and move the substrate. A substrate holding part,
A detection system for detecting the first mark or the second mark formed on the substrate;
A transfer mechanism for delivering the substrate to the plurality of pins of the substrate holding unit,
With respect to the horizontal position, the substrate holding unit is positioned when the transport mechanism passes the substrate to the plurality of pins, and the substrate passed from the transport mechanism to the plurality of pins is moved up and down. Different from the second position where the substrate holding part is located when passing to the suction part using a mechanism,
After the transfer mechanism has passed the substrate to the plurality of pins, the substrate moves in accordance with the movement between the substrate and the suction portion so as to move away from the substrate holding portion of the transfer mechanism with respect to the horizontal direction. The holding portion moves from the first position toward the second position;
The detection system detects the first mark of the substrate holding portion moved to the second position;
A positioning device characterized by that. A step of exposing a substrate using the exposure apparatus according to claim 1;
Developing the exposed substrate;
A device manufacturing method comprising: A lithographic apparatus for forming a pattern on a substrate using an original plate,
A suction part for sucking the substrate, a pin for transferring the substrate, and a lifting mechanism for moving the suction part relatively up and down, and a first mark, are movable by sucking the substrate by the suction part. A substrate holder,
A detection system for detecting the first mark or the second mark formed on the substrate;
A transfer mechanism for delivering the substrate to the plurality of pins of the substrate holding unit,
With respect to the horizontal position, the substrate holding unit is positioned when the transport mechanism passes the substrate to the pin, and the substrate passed from the transport mechanism to the pin is moved using the lifting mechanism. Different from the second position where the substrate holding part is located when adsorbing to the adsorption part,
After the transport mechanism passes the substrate to the pin, the transport mechanism moves between the substrate and the suction unit so as to move away from the substrate support unit with respect to the horizontal direction. Moves from the first position to the second position,
The lithographic apparatus, wherein the detection system detects the first mark of the substrate holding portion moved to the second position.

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