JP2009135166A - Exposure method and exposure device, exposure unit, and device manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently expose a plurality of regions on a substrate with corresponding patterns. <P>SOLUTION: An exposure method of exposing a plurality of different regions on a wafer W2 includes a process of holding the wafer W2 on a simple stage 13 and measuring first measurement information including position information of at least one of a direction along a surface of the wafer W2 and a normal direction on the surface, a process of exposing a non-device region on the wafer W2 based upon the first measurement information, a process of mounting the wafer 2 on a wafer stage WST, and a process of driving the wafer stage WST using the first measurement information to expose device regions on the wafer W2. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an exposure technique for exposing a plurality of different areas on a substrate, for example, exposing a pattern related to a pattern exposed in a complete shot area on a substrate to a missing shot area on a substrate. Applicable to the case. Furthermore, the present invention relates to a device manufacturing technique using the exposure technique.

  For example, in a lithography process for manufacturing various devices (electronic devices, microdevices) such as a semiconductor device or a liquid crystal display element, a wafer (or glass plate or the like) coated with a resist on a reticle (or photomask) pattern An exposure apparatus such as a batch exposure type projection exposure apparatus such as a stepper or a scanning exposure type projection exposure apparatus (scanning type exposure apparatus) such as a scanning stepper is used for transferring and exposing the upper surface.

  A missing shot area (hereinafter referred to as a missing shot) that partially protrudes from the effective exposure area at the periphery of the wafer exposed by these exposure apparatuses is a part that cannot be used as a device, and thus is originally exposed. There is no need to do. However, in recent device manufacturing processes, a CMP (Chemical & Mechanical Polishing) process, which is chemical mechanical polishing, may be applied to planarize the surface of a wafer on which a pattern is formed. When this CMP process is applied, it is necessary to form a resist pattern having a level difference (or periodicity or pattern density) similar to that of the central portion in the peripheral portion of the wafer after exposure and development. In this case, if the reticle pattern is exposed even for those missing shots in the exposure apparatus, the throughput is lowered.

In view of this, for example, an exposure unit that includes a simple exposure optical system installed in a developing device and exposes only a missing shot at the peripheral portion of the wafer has been proposed (see, for example, Patent Document 1). Also, an exposure apparatus has been proposed in which an auxiliary pattern plate is installed in the vicinity of the reticle of the reticle stage of the exposure apparatus, and a chip shot on the wafer is efficiently exposed through the pattern of the auxiliary pattern plate. (For example, refer to Patent Document 2).
JP-A-5-259069 JP 2006-278820 A

Conventional exposure units for chip shot exposure do not include a high-precision alignment mechanism or the like, and it is difficult to accurately expose only chip shots on a wafer. However, if the alignment for missing shot exposure and the alignment for actual device pattern exposure are all performed in an overlapping manner, the throughput may be reduced.
On the other hand, in an exposure apparatus provided with an auxiliary pattern plate on the reticle stage, since the original complete shot area on the wafer cannot be exposed during exposure to a missing shot, the rate of improvement in throughput is not so large. was there.

  In view of such circumstances, the present invention is an exposure technique and device capable of efficiently exposing patterns corresponding to a plurality of regions (for example, a region including a complete shot region and a region including a missing shot) on a substrate such as a wafer. The purpose is to provide manufacturing technology.

  An exposure method according to the present invention is an exposure method in which a plurality of regions including different first and second regions on a substrate are exposed, the holding mechanism (13) holds the substrate, and the direction along the surface of the substrate And a first step (steps 103 to 105) for measuring first measurement information including position information of at least one of the substrates in the normal direction of the surface; on the substrate based on the first measurement information A second step (step 105) for exposing the second region (65ND); a third step (step 108) for placing the substrate on a movable substrate holding body movable in a two-dimensional plane; And a fourth step (steps 111 to 113) of driving the substrate holding movable body using the measurement information of 1 to expose the first region (65D) on the substrate.

  An exposure apparatus according to the present invention, in an exposure apparatus that exposes a plurality of regions on a substrate, holds a substrate and can move a substrate holding movable body (WST) in a two-dimensional plane; and holds the substrate. A holding mechanism (13); a transport system (5) for moving the substrate from the holding mechanism to the substrate holding movable body; a direction along the surface of the substrate held by the holding mechanism and a normal line of the surface A first measurement device (26B, 29, 48B) for measuring first measurement information including position information of the substrate in at least one of the directions; a first region on the substrate held by the substrate holding movable body ( A first optical system (PL) that exposes 65D) with the first exposure light; and a second region (65ND) that is different from the first region on the substrate held by the holding mechanism is exposed with the second exposure light. A second optical system (40) that Based on the first measurement information measured by the first measurement device, the positional relationship between the substrate and the second optical system is controlled, and the second region on the substrate is defined by the second optical system. After exposing and moving the substrate from the holding mechanism to the substrate holding movable body by the transport system, the positional relationship between the substrate and the first optical system is controlled based on the first measurement information. The first region on the substrate is exposed by the first optical system.

  The exposure unit according to the present invention is an exposure unit (150) used together with an exposure main body (140) that exposes a first area (65D) of different first and second areas on a substrate. Measurement information including positional information of the substrate in at least one of the direction along the surface of the substrate held by the holding mechanism and the normal direction of the surface. A measuring device (26B, 29, 48B) for measuring; an optical system (40) for exposing the second region (65ND) on the substrate held by the holding mechanism; and the measurement information measured by the measuring device And a control system (20B) for supplying to the exposure main body.

  According to the present invention, exposure of a substrate (first substrate) on a substrate holding movable body (exposure main body) to a first region (for example, a region including a complete shot region) and a substrate on a holding mechanism (second Since the exposure to the second region (for example, the region including the missing shot) of the substrate) can be performed substantially in parallel, the patterns corresponding to the first and second regions of each substrate can be efficiently exposed. Further, the first position information of the substrate measured on the holding mechanism is used when exposing the substrate on the substrate holding movable body (exposure main body portion), so that the substrate holding movable body (exposure main body portion) is used. ) Substrate position measurement time can be shortened. Therefore, the throughput of the exposure process can be further improved.

[First Embodiment]
Hereinafter, a preferred first embodiment of the present invention will be described with reference to FIGS. FIG. 1 schematically shows the overall configuration of an exposure apparatus 100 according to the present embodiment. The exposure apparatus 100 is a scanning exposure type projection exposure apparatus composed of a scanning stepper (scanner), a main body section 140, a chip shot exposure unit 150, and a wafer transfer between the chip shot exposure unit 150 and the main body section 140. And a wafer loader system 96 (see FIG. 10) including the wafer arm 5 to be performed.

  In FIG. 1, a main body 140 of an exposure apparatus 100 includes a light source and an illumination optical system, and an illumination system 10 that illuminates a reticle R (mask) with exposure light (exposure illumination light) IL as an exposure beam, and a reticle. A reticle stage RST that moves while holding R, and a device region 65D comprising a complete shot region on a wafer (wafer W1 in FIG. 1) as a substrate by exposure light IL via the reticle R (see FIG. 5A). ) And a wafer stage WST that holds and moves the wafer W1. Further, the main body 140 includes an alignment sensor 26A that detects an alignment mark on the wafer W1, a pre-alignment sensor (hereinafter referred to as a PA sensor) 48A that detects the outer shape of the wafer W1, an exposure operation by the projection optical system PL, and the like. And a first control system 20A composed of a computer for overall control.

  Further, the missing shot exposure unit 150 exposes at least a part of the non-device region 65ND (see FIG. 5A) including the missing shot on the wafer (wafer W2 in FIG. 1) with the exposure light ILA. 40, a simple stage 13 that holds and moves the wafer W2, an alignment sensor 26B that detects an alignment mark on the wafer W2, a PA sensor (pre-alignment sensor) 48B that detects the outer shape of the wafer W2, and a missing shot exposure. And a second control system 20B composed of a computer for controlling the exposure operation by the system 40. The first control system 20A and the second control system 20B exchange information such as measurement information and operation timing.

  As an example, as shown in FIG. 10, the wafer loader system 96 includes a main body 96a, a lifting shaft 96b, a first rotating arm 96c rotatable with respect to the lifting shaft 96b, a second rotating arm 96d, The wafer arm 5 is rotatably provided at the tip of the two-rotating arm 96d, and a control system (not shown) for controlling the operation of these members. Hereinafter, in FIG. 1, the Z-axis is taken in parallel with the optical axis AX of the projection optical system PL, and in a direction parallel to the plane of FIG. 1 within a plane perpendicular to the Z-axis (substantially parallel to the horizontal plane in this embodiment). The X axis will be described by taking the Y axis in the direction perpendicular to the paper surface of FIG. The scanning direction of reticle R and wafer (wafer W1 etc.) at the time of scanning exposure in main body 140 is the Y direction (the direction parallel to the Y axis).

  In the main body 140 of FIG. 1, the illumination optical system in the illumination system 10 is an optical integrator as disclosed in, for example, Japanese Patent Application Laid-Open No. 2001-313250 (corresponding US Patent Application Publication No. 2003/0025890). It includes an illuminance uniformizing optical system including a diffractive optical element and a fly-eye lens, a relay lens system, a reticle blind (field stop), a condenser lens system, and the like. The illumination system 10 illuminates the slit-shaped illumination area on the reticle R defined by the reticle blind with the exposure light IL with a substantially uniform illuminance distribution. As the exposure light IL, for example, ArF excimer laser light (wavelength 193 m) whose oscillation wavelength has been narrowed to reduce chromatic aberration is used. As the exposure light IL, KrF excimer laser light (wavelength 193 nm), harmonics of a solid-state laser (YAG laser, semiconductor laser, etc.), or a bright line of a mercury lamp can be used.

  A reticle stage RST that holds the reticle R is placed on a guide surface on a reticle base (not shown) and is driven at a scanning speed specified in the Y direction by a reticle stage drive unit (not shown) including a linear motor and the like. At the same time, it is finely driven in the X direction, the Y direction, and the rotational direction (θZ direction) around an axis parallel to the Z axis. The position of the reticle stage RST on the guide surface is always measured by a reticle interferometer (not shown) with a resolution of about 0.5 to 0.1 nm, for example. Based on the position information, the reticle stage control unit in the first control system 20A controls the position and speed of the reticle stage RST via the reticle stage driving unit.

  In FIG. 1, the projection optical system PL is, for example, both-side telecentric and has a predetermined projection magnification (for example, 1/4 or 1/5). When the illumination area of the reticle R is illuminated by the exposure light IL from the illumination system 10, an image of the circuit pattern in the illumination area is passed through the projection optical system PL by the exposure light IL that has passed through the reticle R. An exposure region 31 (see FIG. 5A) elongated in the X direction on the upper one shot region. Wafers W1 and W2 are made of, for example, a resist (photosensitive agent) that is exposed to exposure light IL on the surface of a disk-shaped substrate having a diameter of about 200 to 300 mm, such as a semiconductor (silicon etc.) or SOI (silicon on insulator). It has been applied. The wafers W1 and W2 are formed with notches W2a (see FIG. 2A) that can detect a rotation angle made of an orientation flat (or notch or the like). Note that the projection optical system PL is a refractive optical system or a catadioptric system (catadioptric system) including a mirror and a lens. The reticle base and the projection optical system PL are supported on a frame (not shown) via a vibration isolation mechanism.

  In FIG. 1, the alignment sensor 26A is arranged on the side surface of the projection optical system PL. The alignment sensor 26A includes an illumination system that irradiates a test mark with illumination light in a relatively wide wavelength range, and a light receiving system with a predetermined magnification that captures an enlarged image of the test mark, and performs image processing on the obtained image. Thus, the FIA (Field Image Alignment) method is used to detect the position of the test mark. As an example, the PA sensor 48A is disposed above the wafer loading position of the main body 140. The PA sensor 48A is an image processing type sensor that picks up an image of the test portion in the same manner as the alignment sensor 26A, but may have a lower magnification than the alignment sensor 26A. Detection signals from the alignment sensor 26A and the PA sensor 48A are supplied to the first control system 20A via the signal processing system 27A. An FIA type alignment sensor is disclosed in, for example, Japanese Patent Application Laid-Open No. 7-183186.

  Further, in FIG. 1, a predetermined liquid (pure water or the like) is supplied by a local liquid immersion method between the tip of the optical member closest to the image plane (wafer side) constituting the projection optical system PL and the wafer W1. A liquid supply system (not shown) is arranged. Thereby, in the main body 140, scanning exposure is performed with an extremely high resolution and a deep focal depth by the liquid immersion method. The liquid supply system is disclosed in, for example, International Publication No. 99/49504 pamphlet or International Publication No. 2004/019128 pamphlet. The main body 140 may perform dry exposure.

  In FIG. 1, wafer stage WST floats in a non-contact manner via a plurality of air bearings on a guide surface (XY plane) perpendicular to the Z axis on wafer base WB arranged horizontally below projection optical system PL. It is supported. Wafer base WB is supported on floor member 1 via a plurality of vibration isolation tables 2A. Wafer W1 is held on wafer stage WST by vacuum chucking (or electrostatic chucking) via wafer holder 36.

  Wafer stage WST includes an XY stage 38 that is driven in the X direction, the Y direction, and the θZ direction by a drive unit (not shown) such as a linear motor or a planar motor on wafer base WB, and a Z / leveling stage 35. , And three actuators 37 (including a voice coil motor, for example) that are disposed on the XY stage 38 so as to support the Z-leveling stage 35 and whose position in the Z direction is variable. The three actuators 37 are independently driven in the Z direction to focus the wafer W1 on the image plane of the projection optical system PL or the observation plane of the alignment sensor 26. The position in the Z direction (focus position) and the inclination angles θX and θY around the axes parallel to the X axis and the Y axis can be controlled.

At least the positions in the X direction, Y direction, and θZ direction on the guide surface of wafer stage WST are constantly measured with a resolution of, for example, about 0.5 to 0.1 nm by a wafer interferometer (not shown). Based on the position information, the first control system 20A controls the position and speed of the wafer stage WST via the stage control unit 21A and the driving unit.
Further, a light transmission system 28a for projecting a plurality of slit images (detection patterns) obliquely onto a test area including an exposure area of the projection optical system PL and an area in the vicinity thereof on the lower side surface of the projection optical system PL; An oblique incidence type multi-point autofocus sensor (hereinafter referred to as an AF system) that measures a focus position of a plurality of measurement points in the test region. 28 is supported by a column (not shown). In a state where wafer stage WST is at position A1 or the like below projection optical system PL, the detection signal of light receiving system 28b of AF system 28 is supplied to signal processing unit 22A, and signal processing unit 22A The defocus amount from the image plane at the focus position of the measurement point is obtained, and the obtained defocus amount is supplied to the first control system 20A. The detailed configuration of the oblique incidence type multi-point AF system is disclosed in, for example, US Pat. No. 5,633,721 and JP-A-2007-48819. The first control system 20A uses the focus position information measured via the AF system 28 and the focus position distribution information (details will be described later) on the surface of the wafer W1 supplied in advance from the second control system 20B. During the scanning exposure, the Z leveling stage 35 is driven so that the exposure area of the wafer W1 is focused on the image plane of the projection optical system PL by the autofocus method.

  On the other hand, in the chipped shot exposure unit 150 of FIG. 1, the simple stage 13 is placed on the base member 12 so as to be movable along a guide portion (not shown), and the base member 12 includes a plurality of vibration isolation stands. It is supported on the floor via the support member 2B. The simple stage 13 includes an X stage 14X driven in the X direction on the base member 12, a Y stage 14Y driven in the Y direction on the X stage 14X, and a position 3 in the Z direction variable on the Y stage 14Y. A Z-leveling stage 15 supported via two actuators 14Z, and a rotary stage 16 mounted on the Z-leveling stage 15 and capable of adjusting the rotation angle in the θZ direction are provided. Further, the wafer W2 is held on the rotary stage 16 by vacuum suction (or electromagnetic suction) via a wafer holder (not shown). Since the wafer loader system 96 (see FIG. 10) of the present embodiment can rotate the wafer, the rotary stage 16 can be replaced with a simple wafer holder.

  The position information including at least the position in the X direction and the Y direction and the rotation angle in the θZ direction with respect to the base member 12 of the rotary stage 16 (wafer W2) of the simple stage 13 is a laser interferometer, optical type, magnetic type, or the like. It is always measured by a high-precision linear encoder with a resolution of about 1 to 0.1 μm, for example. Since the positioning accuracy of the exposure pattern in the missing shot exposure unit 150 only needs to be smaller than the width of the scribe line area between shot areas on the wafer (for example, about 50 μm), the measurement accuracy of the position of the simple stage 13 is also the same as that of the wafer stage WST. It may be coarser than the position measurement accuracy. On the basis of the position information, the second control system 20B uses the stage control unit 21B and a drive unit (not shown) such as a linear motor or a feed screw type drive motor, and the position of the simple stage 13 in the X and Y directions. The speed and the rotation angle of the rotary stage 16 are controlled.

  For example, in order to smoothly load and unload the wafer onto and from the simple stage 13 by the wafer arm 5 (wafer loader system 96), an elevating mechanism for raising and lowering the simple stage 13 in the Z direction along the support member 2B may be provided. Good. In this case, the elevating mechanism is provided with a linear encoder or the like for measuring the Z position of the simple stage 13, and the second control system 20 </ b> B controls the Z position of the simple stage 13 based on this measurement value.

  A chip shot exposure system 40 is disposed above the simple stage 13 while being supported by a frame (not shown). The chip shot exposure system 40 includes an optical member 41 that emits exposure light ILA guided from a light source (not shown) through a light guide, a condenser optical system 42 that illuminates the irradiated surface with the exposure light ILA, and an irradiated surface. A movable reticle 43 that also serves as a field stop, a mirror 44 that bends light from the reticle 43, and an image 63X or 63Y of a line and space pattern (hereinafter referred to as an L & S pattern) formed on the reticle 43. (See FIG. 2B or FIG. 2C) In FIG. 2B or FIG. 2C, a rectangular exposure area 46A or 46C that is elongated in the X direction or Y direction on the wafer W2 on the simple stage 13. And a projection system 45 to be formed).

  The exposure light ILA has the same wavelength (193 nm) as the exposure light IL (ArF excimer laser light in the present embodiment) used to expose the wafer via the projection optical system PL. However, as will be described later, the resolution of the missing shot exposure system 40 may be roughly several times to several tens of times higher than the resolution of the projection optical system PL. Therefore, it is also possible to use ArF excimer laser light having a wider wavelength width than the exposure light IL as the exposure light ILA. Thereby, since the illuminance (pulse energy) of the exposure light ILA can be increased, the resist on the wafer can be exposed in a short time. Further, the resists on the wafers W1 and W2 are sensitive to ArF excimer laser light. However, when the resist is sensitive to KrF excimer laser light (wavelength 248 nm), the exposure light ILA is longer than the exposure light IL. It is also possible to use KrF excimer laser light having a wavelength. As a result, the cost of the light source of the chipped shot exposure system 40 can be reduced.

  FIG. 2A is a plan view showing the simplified stage 13 of FIG. In FIG. 2A, an exposure area 46A elongated in the X direction of the defective shot exposure system 40 is switched to an exposure area 46C elongated in the Y direction by sliding the reticle 43 of FIG. 1 through a drive mechanism (not shown). be able to. In this case, as shown in FIG. 2B, an L & S pattern image 63X having a period QX is projected in the X direction on the exposure area 46A elongated in the X direction. By scanning the wafer W2 in the Y direction with the simple stage 13 with respect to the exposure area 46A, an L & S pattern image 64X having a period QX is exposed in the X direction on the wafer W2. On the other hand, as shown in FIG. 2C, an L & S pattern image 63Y having a cycle QY (equal to QX) is projected in the Y direction on the exposure area 46C elongated in the Y direction. By scanning the wafer W2 in the X direction with the simple stage 13 with respect to the exposure area 46C, the L & S pattern image 64Y having the period QY is exposed in the Y direction on the wafer W2.

  The width in the X direction of the exposure area 46A of the chip shot exposure system 40 and the width in the Y direction of the exposure area 46C are respectively the width in the X direction of the exposure area 31 of the projection optical system PL (the X direction width of the shot area on the wafer). Less than the width). However, the exposure areas 46A and 46C may be made as large as the exposure area 31 in order to further improve the efficiency of the missing shot exposure. In the present embodiment, one shot exposure system 40 is provided. However, in order to efficiently perform exposure of a missing shot, a plurality of missing shot exposure systems may be provided.

  Returning to FIG. 1, the FIA method (image processing method) alignment is the same as the alignment sensor 26 </ b> A on the main body 140 side on the side surface of the chipped shot exposure system 40 above the simple stage 13, but with a small magnification (wide field of view). A sensor 26B and a PA sensor 48B of the same image processing type as the PA sensor 48A are supported by a frame (not shown). Detection signals from the alignment sensor 26B and the PA sensor 48B are supplied to the second control system 20B through the signal processing system 27B. The alignment sensors 26A and 26B may include an autofocus system that measures the defocus amount from the best focus position of the test surface. In this case, during alignment, the alignment of the alignment sensors 26A and 26B may be performed by driving the wafer stage WST and the simple stage 13 in the Z direction so that the defocus amount is within an allowable range.

  The field of view 26BF of the alignment sensor 26B and the field of view 48BF of the PA sensor 48B that is wider than the field of view 26BF are arranged substantially along the Y axis as shown in FIG. 2A as an example. Further, when the simple stage 13 is moved to the wafer loading position and the wafer W2 is loaded from the wafer loader system (not shown) onto the simple stage 13, the position A2 on the notch W2a of the wafer W2 is the PA sensor 48B. Are arranged so as to be within the visual field 48BF. In this case, the simple stage 13 is further driven to move another position A3 of the notch W2a of the wafer W2 and an edge portion of the position A4 in the + X direction of the wafer W2 into the field of view 48BF, respectively. By measuring the position of the edge portion, the second control system 20B in FIG. 1 performs pre-alignment based on the outer shape reference of the wafer W2, that is, alignment marks (here, search alignment marks) attached to each shot area on the wafer W2. ) Can be recognized.

  In order to efficiently perform pre-alignment of the wafer on the simple stage 13, the same as the PA sensor 48B on the positions A2, A3, and A4, respectively, with the simple stage 13 in the loading position in FIG. The PA sensor may be arranged. Further, when the movement stroke of the simple stage 13 in the X direction and the Y direction is narrow, a moving mechanism including a linear encoder for moving the alignment sensor 26B and the PA sensor 48B in the X direction and the Y direction, respectively, may be provided. Good.

  Further, as shown in FIG. 1, in order to measure the focus position (position in the Z direction) of the surface of the wafer W2 in the exposure area of the missing shot exposure system 40 and in the vicinity area (test area), a light transmission system An oblique incidence type multi-point autofocus sensor (hereinafter referred to as AF system) 29 including a light receiving system 29b and a light receiving system 29b is supported by a column (not shown). The detection signal of the light receiving system 29b of the AF system 29 (surface position detection device) is supplied to the signal processing unit 22B, and the signal processing unit 22B performs the missing shot exposure system 40 (projection) of the focus position of each measurement point in the test area. A defocus amount from the image plane of the system 45) is obtained, and distribution information (focus position information) of the obtained defocus amount is supplied to the second control system 20B. Based on the measurement value of the defocus amount, the second control system 20B uses the autofocus method to adjust the Z leveling stage 15 so that the exposure area on the wafer W2 is focused on the image plane of the missing shot exposure system 40. And the obtained focus position information is supplied to the first control system 20A.

  FIG. 4A shows a configuration example of the AF system 29 of the missing shot exposure unit 150 of FIG. 4A, a light transmission system 29a includes light sources 70A and 70B made of, for example, light emitting diodes (LEDs), a light transmission slit prism 72A having a tilt arrangement on which slit members 72Aa having a plurality of slits are attached, And a light transmitting prism 72B having a tilt arrangement to which an opening member 72Ba having a rectangular opening is attached. Further, the light transmission system 29a condenses the detection light from the condenser lenses 71A and 71B that guide the detection light from the light sources 70A and 70B to the slit member 72Aa and the opening member 72Ba, respectively, and the slit member 72Aa and the opening member 72Ba. 1 objective lenses 73A and 73B, a beam splitter 74 for combining the detection light from the first objective lens 73A and the detection light from the first objective lens 73B via the mirror 76, and the detection light from the beam splitter 74 as wafer W2. And a second objective lens 75 for irradiating the upper test surface. The image of the plurality of slits of the slit member 72Aa and the image of the opening of the opening member 72Ba are projected on the same region on the surface to be examined.

  On the other hand, the light receiving system 29b collects the reflected light from the test surface to form a plurality of slit images and forms a plurality of slit images, and for example, captures the plurality of slit images. The image pickup device 79 is included. As the imaging element 79, a one-dimensional CCD type or CMOS type line sensor, a TDI (Time Delayed Integration) sensor, or the like can be used. In this case, as an example, the light sources 70A and 70B are alternately turned on, and an image 72AP including a plurality of slit images 32 of the slit member 72Aa and the aperture member 72Ba are illuminated by the image sensor 79 as shown in FIG. Images 72BP including an image of the opening are alternately captured. Then, the position of the slit image 32 can be obtained with high accuracy from the image 72C obtained by subtracting the image 72BP from the image 72AP without being influenced by the ground pattern on the surface to be measured, and thus a plurality of corresponding measurements. The focus position of a point can be measured with high accuracy. As the AF system 29, the AF system 28 and the AF system shown in FIG.

  In FIG. 2A, an illuminance unevenness sensor 51 and an irradiation amount sensor 52 for measuring the illuminance and the irradiation amount of the exposure light ILA, respectively, in the vicinity of the wafer W2 on the upper surface of the simple stage 13 (rotary stage 16), and a reference A reference member on which the mark 53 and the light receiving window 54 are formed is installed. An aerial image measurement system 55 is installed inside the rotary stage 16 on the bottom surface of the light receiving window 54. As shown in FIG. 3A, the aerial image measurement system 55 includes an imaging system 56 that forms the exposure light ILA transmitted through the light receiving window 54, a mirror 57 that bends the exposure light ILA, and an image of the exposure light ILA. And a two-dimensional imaging element 58 of a CCD type or a CMOS type. Detection signals from the illuminance unevenness sensor 51, the dose sensor 52, and the image sensor 58 are supplied to the second control system 20B in FIG. 1 via a signal processing system (not shown).

  As an example, an index mark (not shown) having a known relationship with the reference mark 53 is formed on the upper surface of the light receiving window 54 in FIG. By measuring the positional relationship between the exposure area 46A (or 46C) of the chipped shot exposure system 40 and the index mark by the aerial image measurement system 55, the positions of the exposure areas 46A and 46C can be measured. Further, by sequentially detecting the reference mark 53 by the alignment sensor 26B and the PA sensor 48B, the positional relationship between the detection centers (field centers) of the alignment sensor 26B and the PA sensor 48B can be obtained. It is stored in the storage unit of the control system 20B. Instead of the imaging type aerial image measurement system 55, as shown in FIG. 3B, a slit plate 59 formed with slits, a condenser lens 60, and a light receiving element 61 such as a photodiode are included. A scanning aerial image measurement system 551 may be used. The aerial image measurement system 551 detects the image position of the test mark by relatively scanning the slit of the slit plate 59 and the image of the test mark.

  In FIG. 1, an illuminance unevenness sensor, a dose sensor, and a reference member on which a reference mark and a light receiving window are formed are also installed in the vicinity of the wafer W1 on the upper surface of the wafer stage WST of the main body 140. In addition, the same aerial image measurement system (not shown) as the aerial image measurement system 55 in FIG. Accordingly, also in the main body 140, the positional relationship (baseline) between the pattern image of the reticle R and the detection center of the alignment sensor 26A, and the positional relationship between the detection center (field center) of the alignment sensor 26A and the PA sensor 48A. Can be requested.

Next, an example of the shot arrangement of the wafer exposed by the exposure apparatus 100 of FIG. 1 of the present embodiment will be described with reference to FIGS. 5 (A) and 5 (B). The following description will be made taking the wafer W2 as an example. Information on the wafer shot arrangement is stored in the storage units of the control systems 20A and 20B.
FIG. 5A is a plan view showing the wafer W2 on the simple stage 13 of FIG. In FIG. 5A, the exposure surface of the wafer W2 is divided into an X direction and a Y direction by a number of shot areas SA having a width DX in the X direction and a width DY in the Y direction. A scribe line area SLA having a width of about 50 μm is provided at the boundary between two adjacent shot areas SA. As an example, the first layer circuit is formed on the wafer W2, and a two-dimensional wafer mark WM as a fine alignment mark and a two-dimensional search alignment mark WMS are formed in each shot area SA.

  As an example, the missing shot exposure unit 150 of the present embodiment detects two search alignment marks WMS1 and WMS2 on the wafer W2, and detects the position of the wafer W2 in the X direction, the Y direction, and the rotation angle in the θZ direction. (Search alignment) is performed. On the other hand, the main body 140 in FIG. 1 detects the positions of wafer marks WM attached to shot areas (hereinafter referred to as sample shots) SA1 to SA10 of a predetermined number (10 in FIG. 5A) of wafers W2. For example, the wafer W2 is aligned by the EGA method.

  Further, in the exposure surface of the wafer W2 in FIG. 5A, the device region 65D including only the complete shot region SA that is entirely included in the effective exposure region is a region surrounded by the boundary line 65 formed by a solid broken line. It is. On the other hand, the area outside the boundary line 65 is a non-device area 65ND including only missing shots (for example, missing shots SAD1, SAD2, etc.) that are shot areas partially protruding from the effective exposure area. The non-device region 65ND is surrounded by a straight line parallel to the scribe line region SLA of the wafer W2 (a straight line parallel to the Y axis or the X axis, for example, a straight line including a part of the boundary line 65) and the edge portion of the wafer W2. The four non-device regions 66A, 66B, 66C, and 66D having a simple shape and the four non-device regions 67A, 67B, 67C, and 67D having a complicated shape surrounded by a boundary portion and an edge portion formed by a broken line. It is configured.

  Furthermore, as shown in FIG. 5 (B), almost the entire shot area SA in the device area 65D of the wafer W2 is passed through the projection optical system PL of the main body 140 in FIG. It is assumed that the L & S pattern 62X or the image 62X or 62Y of the L & S pattern close to the resolution limit of the cycle PY in the Y direction is exposed. At this time, if a CMP (Chemical & Mechanical Polishing) process is executed in a later process, the non-device region 65ND on the wafer W2 has the same periodicity as the image 62X or 62Y (however, the period may be coarse). Alternatively, it is preferable to expose an image of a dense L & S pattern.

  Therefore, as an example, the four non-device regions 66A, 66B and 66C, 66D having a simple shape in the non-device region 65ND are arranged in the X direction shown in FIG. 2B using the missing shot exposure system 40 of FIG. It is assumed that the L & S pattern image 64X and the L & S pattern image 64Y in the Y direction shown in FIG. The periods QX and QY of the images 64X and 64Y are about 5 to 20 times the periods PX and PY of the images 62X and 62Y of the L & S pattern of FIG. 5B exposed in the complete shot area SA. Further, since the line widths of the line portions (bright portions) of the images 62X and 62Y are approximately ½ of the periods PX and PY, the line widths of the line portions of the images 64X and 64Y are the line portions (bright portions of the images 62X and 62Y). Part) is about 5 to 20 times the line width. If the resolution of the chipped shot exposure system 40 can be made fine, the line width of the image of the L & S pattern exposed in the non-device regions 66A to 66D may be made smaller than 5 times the above. Furthermore, when no problem occurs in the CMP process, the line width of the image of the L & S pattern exposed in the non-device regions 66A to 66D may be larger than the above 20 times.

  Further, the L & S pattern image 64X or 64Y is exposed to the four non-device regions 67A to 67D having complicated shapes in the non-device region 65ND of FIG. Shall. Note that the images 62X and 62Y of the pattern of the reticle R may be exposed to the four non-device regions 67A to 67D having complicated shapes via the projection optical system PL of FIG. As described above, the exposure time for the wafer as a whole may be shortened by sharing the exposure of the non-device region 65ND by the chip shot exposure systems 40A to 40D and the projection optical system PL.

  Next, an example of the exposure operation of the exposure apparatus 100 of FIG. 1 will be described with reference to the flowchart of FIG. The operations in steps 101 to 107 in FIG. 8 (operations performed by the missing shot exposure unit 150 under the control of the second control system 20B) and the operations in steps 110 to 115 (control of the first control system 20A). And the operation executed by the main body 140). Further, the operation of step 108 is executed by the main body 140 and the missing shot exposure unit 150.

  First, the operation on the missing shot exposure unit 150 side will be described. In step 101 of FIG. 8, the position of the exposure area 46A (and 46C) of the missing shot exposure system 40 is measured in advance using the aerial image measurement system 55 of the simple stage 13 of FIG. The reference mark 53 is detected. From this detection result, the second control system 20B obtains baseline information of the missing shot exposure system 40, which is the positional relationship between the position of the exposure region 46A (and 46C) and the detection center (field center) of the alignment sensor 26B. Can do.

Next, as shown in FIG. 1, assuming that the wafer W1 is loaded on the wafer stage WST of the main body 140, the simple stage 13 is moved to the wafer loading position in FIG. The wafer W2 is loaded. A resist is applied to the wafer W2 by a coater / developer (not shown) (step 121).
In the next step 103, the pre-alignment of the wafer W2 is performed by detecting the position and rotation angle of the wafer W2 on the simple stage 13 using the PA sensor 48B of FIG. This makes it possible to drive the search alignment mark WMS in each shot area SA of the wafer W2 in FIG. 5A into the field of view of the alignment sensor 26B in FIG. It should be noted that step 103 can be omitted when the pre-alignment of wafer W2 is completed in a wafer loader system (not shown). From this stage, the focus position of the surface of the wafer W2 is measured by the AF system 29 of FIG.

  In the next step 104, the simple stage 13 is moved below the alignment sensor 26B, and the two search alignment marks WMS1, WMS2 on the wafer W2 in FIG. 5A are detected by the alignment sensor 26B. An offset in the X direction and Y direction of the shot arrangement and a rotation angle in the θZ direction are obtained. At this time, the second control system 20B in FIG. 1 rotates the rotation stage 16 in FIG. 1 so that the rotation angle in the θZ direction is within a predetermined allowable range, and then performs a shot based on the outer shape reference of the rotated wafer W2. Information on the X direction and Y direction offsets (ΔX, ΔY) of the array is stored as alignment information.

Further, by this search alignment, the second control system 20B can recognize the position of the non-device area 65ND on the wafer W2 with an accuracy smaller than the width of the scribe line area SLA. As a result, the non-device area 65ND is missing shot exposure. The system 40 allows accurate exposure.
In the next step 105, while the focus position of the surface of the wafer W2 is measured by the AF sensor 29 of FIG. 1 and the focus on the missing shot exposure system 40 based on the measurement result is performed, the simple stage in the non-device region 65ND is performed. The image of the L & S pattern is sequentially exposed by the missing shot exposure system 40 in an area where the amount of movement 13 is small.

  Specifically, the simple stage 13 is driven to position the exposure region 46A (not exposed to the exposure light ILA in this state) at the position A6 as shown in FIG. Then, irradiation of the exposure light ILA to the exposure area 46A is started, the simple stage 13 is scanned in the + Y direction, and then the simple stage 13 is stepped by a predetermined amount in the −X direction so that the exposure area 46A is positioned. Move to A7. Then, by scanning the simple stage 13 in the −Y direction, the exposure area 46A moves along the locus TA, and the edge portion of the exposure area 46A moves within the boundary portion 65a of the device area 65D. The L & S pattern image 64X of FIG. 2B is accurately exposed in 66A. At this time, the illuminance (product of pulse energy and frequency) of the exposure light ILA and the relative scanning speed are controlled so that the exposure amount in the non-device region 66A exceeds the resist sensitivity. Irradiation of exposure light ILA is stopped after scanning exposure.

  Next, the exposure area 46A is moved to the position B1, the irradiation of the exposure light ILA is started, and the exposure area 46A is moved along the locus TB passing through the position B2, so that the non-device area 66B also has the L & S pattern. Image 64X is exposed. When the widths in the X direction of the non-device areas 66A and 66B are narrow, the entire exposure area 46A may be exposed only by performing relative scanning once between the exposure area 46A and the wafer W2 in the Y direction.

  Next, as shown in FIG. 7, an exposure area 46C is set by the defective shot exposure system 40, the exposure area 46C is positioned at a position B3, and the exposure area 46C is relatively moved along a locus TC passing through the position B4. To do. Thereafter, the exposure area 46C is positioned at the position B5, and the exposure area 46C is relatively moved along the trajectory TD passing through the position B6, whereby the image of the L & S pattern of FIG. 2C is obtained in the non-device areas 66C and 66D. 64Y is exposed. Similarly, the remaining non-device regions 67A to 67D in FIG. 7 are scanned and exposed with the L & S pattern image 64X or 64Y, respectively.

In the next step 106, it is finally determined whether or not a non-device area (missing shot area) to be exposed by the missing shot exposure system 40 remains. If there is a non-device area to be exposed, operation returns to step 105.
On the other hand, if there is no non-device area to be exposed in step 106, the operation proceeds to step 107, and the second control system 20B in FIG. Information (alignment information) of offsets (ΔX, ΔY) in the X and Y directions of the shot arrangement based on the outer shape reference of the wafer W2 is sent to the first control system 20A. Further, the second control system 20B obtains distribution information (focus position information) of the focus position on the surface of the wafer W2 from the measurement value obtained by the AF system 29 during the exposure of the missing shot, and the focus position of the wafer W2 Information is sent to the first control system 20A. At this stage, in FIG. 1, the exposure of the pattern image of the reticle R on another wafer W1 is completed on the main body 140 side, and the wafer W1 is unloaded.

  Next, in step 108, the wafer arm 2 (wafer loader system 96) in FIG. 1 maintains the rotation angle of the wafer W2 with respect to the wafer stage WST of the main body 140 from the simple stage 13 of the chip shot exposure unit 150. Loaded. Thereafter, the operation of the defective shot exposure unit 150 returns to step 101, and the defective shot exposure for the next wafer to be exposed is performed. Note that the exposure operation may be started from step 102 with step 101 omitted for the second and subsequent wafers in one lot.

  Next, the operation on the main body 140 side of the exposure apparatus 100 in FIG. 1 will be described. In step 110 subsequent to step 108, on the main body 140 side, pre-alignment of the wafer W2 is performed by measuring the rotation angle and the X-direction and Y-direction positions of the wafer W2 using the PA sensor 48A. The first control system 20A adds the offset (ΔX, ΔY) in the X direction and Y direction of the shot arrangement based on the outer shape reference of the wafer W2 sent from the second control system 20B to the result of this pre-alignment. Thus, the wafer mark WM (see FIG. 5A) in each shot area SA of the wafer W2 can be driven into the visual field of the alignment sensor 26A in FIG. In other words, in the main body 140 of the present embodiment, search alignment can be omitted using the alignment information on the missing shot exposure unit 150 side, so that the throughput of the exposure process is improved.

Therefore, in the next step 111, while driving the wafer stage WST of FIG. 1, the wafer marks WM of the sample shots SA1 to SA10 of FIG. The coordinates of the wafer mark WM of SA10 are measured, and fine alignment of the wafer W2 is performed.
In the next step 112, the first control system 20A processes the measurement values of the coordinates of the wafer marks WM by, for example, the EGA method, and obtains the array coordinates of all shot areas of the wafer W2. Further, the first control system 20A determines, for example, one focus position (in this case, the defocus amount with respect to the image plane of the projection optical system PL) measured by the AF system 29 on the wafer W2 via the AF system 28, for example. measure. Then, using this measurement value, the distribution information of the focus position of the wafer W2 supplied from the second control system 20B is converted into the distribution of the defocus amount from the image plane of the projection optical system PL. Thereafter, the defocusing amount is driven small by driving the Z-leveling stage 35 in advance to align the surface of the exposure area of the wafer W2 with the image plane, so that the alignment based on the measurement value of the AF system 28 is performed. Focusing can be performed at high speed and with high accuracy.

  In the next step 113, while performing the focus position measurement and focusing on the wafer W2 on the wafer stage WST, the image of the pattern of the reticle R is scanned and exposed by the immersion method on each shot area on the wafer W2. Specifically, wafer stage WST2 in FIG. 1 is driven in the X and Y directions, and wafer W2 (placed in place of wafer W1) is stepped to the scan start position. Subsequently, supply of liquid between the projection optical system PL and the wafer is started, irradiation of the exposure light IL is started, and in synchronization with scanning of the reticle R in the Y direction via the reticle stage RST. Then, scanning exposure is performed through wafer stage WST by scanning one shot area on wafer W2 with respect to the exposure area of projection optical system PL in the direction corresponding to the projection magnification as the speed ratio. By the step-and-scan operation in which the step movement and the scanning exposure are repeated, the exposure area 31 of the projection optical system PL and the wafer W2 relatively move as shown by a locus A5 in FIG. An image of the pattern of the reticle R is transferred to each shot area of the device area 65D on W2.

  In the next step 114, the wafer stage WST is moved to the unloading position. After the wafer W2 is unloaded in step 115, the process proceeds to step 108, where the next wafer to be exposed is removed as a chip shot exposure unit. Transfer from 150 to the main body 140 side. Thereafter, the alignment and exposure operations after step 110 are repeated. On the other hand, the exposed wafer W2 unloaded in step 115 is transferred from the main body 140 to a coater / developer (not shown), and in step 122, the resist on the wafer is developed. In the next step 123, substrate processing including heating (curing) of the developed wafer, etching process, CMP process and the like is performed. In the next step 124, the lithography process and the substrate processing process are repeated as necessary, and then the semiconductor is subjected to a device assembly step (including processing processes such as a dicing process, a bonding process, and a packaging process), an inspection step, and the like. Devices such as devices are manufactured. At this time, an image of an L & S pattern having a predetermined periodicity is exposed on almost the entire exposure surface of the wafer W2 in FIG. 5A of this embodiment, and the cycle is applied to almost the entire surface of the wafer by development and substrate processing. Since the pattern having the characteristics is formed, the CMP process can be easily performed.

Further, the exposure operation to the defective shot on the wafer by the defective shot exposure unit 150 in steps 101 to 107 in FIG. 8 and the exposure operation to the complete shot area on the wafer by the main body 140 in steps 110 to 115 are parallel. To be executed. Therefore, as a whole, one lot of wafers can be efficiently exposed with high throughput.
Effects and the like of this embodiment are as follows.

  (1) The exposure method using the exposure apparatus 100 (main body 140, wafer loader system 96, and chip shot exposure unit 150) in FIG. 1 is the same as the device region 65D (first region) shown in FIG. In this exposure method, a plurality of regions including a device region 65ND (second region) are exposed. In this exposure method, the wafer W2 is held on the simple stage 13 (holding mechanism) on the missing shot exposure unit 150 side, and information on the outer shape of the wafer W2 and the positions of the search alignment marks WMS1 and WMS2 (alignment information) and the focus position. Steps 103 to 105 (first process) for measuring information (first measurement information), step 105 (second process) for exposing the non-device region 65ND on the wafer W2 based on the alignment information, Have

  Further, the exposure method includes step 108 (third step) for placing wafer W2 on wafer stage WST (substrate holding movable body) movable in a two-dimensional plane (guide surface), and main body 140 side. After measuring the wafer mark on the wafer W2 using the alignment information, the wafer stage WST is driven using the focus position information to expose the device region 65D on the wafer W2 in steps 110 to 113 (fourth step). ).

  According to the present embodiment, the exposure to the device region 65D including the complete shot region on the wafer and the exposure to the non-device region 65ND including the chipped shot on another wafer can be efficiently executed substantially in parallel. . Further, by using the alignment information of the wafer W2 measured on the simple stage 13 on the main body 140 side, the search alignment can be omitted on the main body 140 side, and the error at the time of measuring the focus position is reduced. Therefore, the throughput of the exposure process can be further improved.

The information sent from the defective shot exposure unit 150 side to the main body 140 side may be at least one of the alignment information or the focus position information of the wafer W2.
(2) On the main body 140 side, the alignment information and focus position information obtained on the missing shot exposure unit 150 side by the alignment sensor 26A, PA sensor 48A, and AF system 28 (second measuring device) are used. Steps 111 and 113 for measuring position information (position information in the direction along the wafer surface) and focus position information (position information in the normal direction of the wafer surface) (second measurement information) on the wafer W2 And step 113 of performing exposure by driving wafer stage WST based on the position information and focus position information of the wafer mark.

  Therefore, fine alignment and autofocus operation of the wafer W2 can be performed with higher accuracy. When the information sent from the missing shot exposure unit 150 side is alignment information or focus position information, the main body 140 side independently performs search alignment and fine alignment of the wafer W2, respectively, or under a wide measurement range. It is preferable to perform focus position measurement.

  (3) In the above embodiment, the X stage 14X and the Y stage 14Y (driving) of the simple stage 13 while the exposure light ILA is irradiated from the chip shot exposure system 40 to the non-device region 65ND on the wafer W2. The defective shot exposure system 40 and the wafer W2 are relatively moved by the mechanism). As a result, for example, predetermined L & S pattern images 64X and 64Y can be efficiently exposed to a series of a plurality of chipped shots on the wafer W2, for example, by the scanning exposure method. Further, for example, since it is only necessary to expose an image of the L & S pattern, it is only necessary to form an L & S pattern having a predetermined cycle in the non-scanning direction on the reticle 43 (see FIG. 1) in the missing shot exposure system 40. It is not necessary to provide a scanning mechanism.

Note that the wafer W2 may be exposed by the step-and-repeat method by the chip shot exposure system 40.
(4) Further, when the line widths of the images 64X and 64Y in the non-device region 65ND are 5 to 20 times the minimum line width of the images 62X and 62Y in the device region 65D, the missing shot exposure system 40 is simplified. In addition, the subsequent CMP process can be performed satisfactorily.

Note that the non-device region 65ND in FIG. 5A may be subjected to exposure with a dose exceeding the resist sensitivity (so-called peripheral exposure) by the missing shot exposure system 40 without exposing a specific pattern. .
(5) The chip shot exposure unit 150 detects a plurality of search alignment marks WMS1 and WMS2 on the wafer W2, and detects at least the position in the X and Y directions and the rotation angle of the wafer W2. (First alignment system) and an AF system 29 (surface position detection device) that measures position information (focus position information) in the normal direction of the surface of the wafer W2. In this case, the alignment sensor 26B may incorporate an autofocus system, and the alignment sensor 26B may also measure the focus position information on the surface of the wafer W2.

Further, the chipped shot exposure unit 150 includes a PA sensor 48B (detection device) that detects positional information of the wafer W2 on the basis of the outer shape. For example, when a pre-alignment sensor is arranged in the wafer loader system, the PA The sensor 48B can be omitted.
(6) Moreover, it is preferable that the wavelength of exposure light IL and the wavelength of exposure light ILA are substantially the same wavelength. As a result, the resist on the wafer can be exposed in a short time by chip shot exposure.

In FIG. 1, the exposure light IL and the exposure light ILA are supplied from different light sources. However, for example, a part of the exposure light IL branched from the illumination system 10 may be used as the exposure light ILA. Further, in the chipped shot exposure unit 150, the light from the light source may be supplied to the chipped shot exposure system 40 via, for example, a mirror without using a light guide.
(7) In addition, the device manufacturing method of the above embodiment uses a step (Step 121) of preparing a resist-coated wafer (photosensitive substrate) and the exposure apparatus 100 of the above embodiment, and a projection optical system. A process (steps 101 to 115) of exposing a predetermined pattern on the wafer via the PL and the chip shot exposure system 40, and developing the exposed wafer, and forming a mask layer having a shape corresponding to the exposed pattern A process for forming the wafer surface (step 122) and a process for processing the wafer surface through the mask layer (step 123) are provided.

In this case, according to the exposure apparatus 100, the wafer including the chip shot can be efficiently exposed, and the CMP process can be favorably performed in the subsequent process, so that an electronic device or the like can be manufactured with a high yield and a high throughput. .
[Second Embodiment]
A second embodiment of the present invention will be described with reference to FIGS. 9 (A) to 9 (C). The exposure apparatus of this embodiment includes a main body 140 in FIG. 1, a wafer arm 5 (wafer loader system 96) in FIG. 1, and a chipped shot exposure unit 150A in FIG. 9A. 9A, parts corresponding to those in FIG. 1 are denoted by the same or similar reference numerals, and detailed description thereof is omitted.

  FIG. 9A is a perspective view showing a schematic configuration of a main part of the missing shot exposure unit 150A of the present embodiment. The chipped shot exposure unit 150A includes a simple stage 13A including a rotary stage 16 mounted on a base member (not shown) via a Z-leveling stage 15 (see FIG. 1, not shown in FIG. 9A), The chipped shot exposure systems 40A and 40A, the alignment sensor 26B, and the PA sensor 48B are provided above the simple stage 13A so as to be movable in the X direction and the Y direction, respectively. Wafer W2 is held on simple stage 13A.

  One chip shot exposure system 40A is formed on the reticle 43, a light guide 41L that guides exposure light ILA from a light source (not shown), a condenser optical system 42, a movable reticle 43 arranged on the irradiated surface, and the reticle 43. A projection system comprising a first projection system 45A and a second projection system 45B that form an image of the L & S pattern in an exposure area 46A (or an area rotated by 90 °) on the wafer W2, and a mirror 44A that bends the exposure light ILA. , 44B, 44C. The other chip shot exposure system 40B is configured symmetrically with the chip shot exposure system 40A, and exposes an image of the L & S pattern on the exposure area 46B (or an area rotated by 90 °) on the wafer W2.

  In addition, the housings (not shown) of the chip shot exposure systems 40A and 40B are respectively AF systems 29A composed of light transmission systems (irradiation systems) 29Aa and 29Ba and light receiving systems 29Ab and 29Bb similar to the AF system 29 of FIG. And 29B are fixed. The light transmission systems 29Aa and 29Ba are arranged so as to face each other. At this time, as shown in FIG. 9A, the detection light DL from the AF systems 29A and 29B is shown in FIG. 9 in a state where the exposure regions 46A and 46B are positioned at both ends in the X direction on the wafer W2. As shown in (B), irradiation is performed from the inside to the outside of the edge of the wafer W2.

  In FIG. 9A, an X-axis guide 82 parallel to the X-axis fixed to a frame (not shown), a Y-axis guide 81 driven in the X direction along the X-axis guide 82, and a Y-axis guide A first drive mechanism including a Y-axis slider 80 driven in the Y-direction along the Y-axis is installed, and a casing (not shown) of the missing shot exposure system 40A is fixed to the Y-axis slider 80. The first drive mechanism incorporates a linear encoder that measures the position in the X direction and the Y direction of the missing shot exposure system 40A. Similarly, the defective shot exposure system 40B, the alignment sensor 26B, and the PA sensor 48B are also driven independently in the X direction and the Y direction by the second, third, and fourth drive mechanisms (not shown). A control system similar to the second control system 20B of FIG. 1 is based on the measurement values of the linear encoders of these drive mechanisms, and the shot missing exposure systems 40A and 40B, the alignment sensor 26B, and the simple stage 13A (wafer W2), The position of the PA sensor 48B is controlled. Other configurations are the same as those of the embodiment of FIG.

According to this embodiment, in addition to the effect of 1st Embodiment, there exists the following effect.
(1) The chipped shot exposure unit 150A of FIG. 9A includes first and second drive mechanisms (such as a Y-axis slider 80) that move the chipped shot exposure systems 40A and 40B (second optical system). When the non-device region 65ND on the wafer W2 of 5A is exposed, the lack shot exposure systems 40A and 40B are moved by the drive mechanism so that the lack shot exposure systems 40A and 40B and the wafer W2 are relatively moved. Scan. Therefore, the configuration on the simple stage 13A side in FIG. 9A can be simplified.

  (2) In FIG. 5A, a non-device region 65ND (second region) on the wafer W2 is a region surrounding the device region 65D (first region), and AF systems 29A and 29B (first measurement). A part of the apparatus irradiates the detection light DL (measurement light) obliquely on the wafer W2 from the inner side to the outer side of the edge of the wafer W2 held on the simple stage 13A. Position information (focus position information) of the wafer W2 in the normal direction of the surface is measured.

  In this case, as shown in FIG. 9B, the scattered light from the edge portion of the wafer W2 is difficult to enter the light receiving systems 29Ab and 29Bb of FIG. Autofocus operation can be performed with high accuracy. On the other hand, as shown in FIG. 9C, when the detection light DL is irradiated from the outer side to the inner side of the edge of the wafer W2, the light receiving systems 29Ab and 29Bb in FIG. There is a possibility that the measurement error of the focus position occurs due to the incident of scattered light or the like.

[Third Embodiment]
A third embodiment of the present invention will be described with reference to FIG. The chipped shot exposure unit 150B of FIG. 10 of the present embodiment is independently installed in, for example, a wafer inspection apparatus or a resist coater / developer separately from the main body of the exposure apparatus.
In the chamber 97 of the wafer inspection apparatus shown in FIG. 10, for example, an inspection apparatus (not shown), a wafer loader system 96 for holding the wafer W3 to be exposed for the defective shot, and a defective shot exposure unit 150B are installed. . The chipped shot exposure unit 150B includes a simple stage 13, a chipped shot exposure system 40G, an alignment sensor 26B, and a PA sensor 48B mounted on the base member 12A supported by the support member 2B. The chip shot exposure system 40G irradiates the reticle 43 with exposure light composed of laser light from a light source 95 such as an excimer laser light source via a beam expander composed of lens systems 42A and 42B and a mirror 44A. Other configurations are the same as those of the missing shot exposure unit 150 of FIG.

As described above, by using the missing shot exposure unit 150B, the alignment in the main body of the exposure apparatus can be simplified, the autofocus can be easily performed, and the burden of the missing shot exposure can be reduced.
The chipped shot exposure system 40 of the chipped shot exposure unit 150 of the embodiment shown in FIG. 1 can be modified as shown in FIGS. 11 (A) to 11 (D) below. 11A to 11D, portions corresponding to those in FIGS. 1 and 9A are denoted by the same reference numerals, and detailed description thereof is omitted.

  First, in the chipped shot exposure system 40C in FIG. 11A, the second projection system is reflected from the wafer W2 by replacing the mirror 44B with a half mirror 44D with respect to the chipped shot exposure system 40A in FIG. 9A. 45B, the mirror 40C, the first projection system 45A, and the photoelectric sensor 84 that receives the exposure light ILA that has passed through the half mirror 44D are inclined to a position conjugate with the surface of the wafer W2 (wafer surface) and to prevent flare. Is provided. In this case, when the chip shot exposure system 40C is used to perform chip shot exposure, the photoelectric sensor 84 can obtain information on the reflectivity of the wafer W2, and this reflectivity information can be obtained from the main body of FIG. It can be used for exposure at 140 (main exposure).

Further, when exposure is performed by the missing shot exposure unit 150 after the main exposure, the exposure amount and the focus state can be calibrated using the detection signal of the photoelectric sensor 84.
Next, the missing shot exposure system 40D in FIG. 11B is obtained by replacing the missing shot exposure system 40C in FIG. 11A by replacing the half mirror 44D with a mirror 44B and replacing the mirror 44C with a dichroic mirror 44E. It is. Further, a light source 85 that generates detection light DL, a condenser lens 86, a beam splitter 87, a correction lens 88, an imaging lens 89, and a two-dimensional image sensor 90 are provided above the dichroic mirror 44E. The dichroic mirror 44E has a wavelength selection characteristic that reflects the exposure light ILA and transmits the detection light DL.

  In this case, the detection light DL from the light source 85 illuminates the wafer surface via the condenser lens 86, the beam splitter 87, the correction lens 87, the dichroic mirror 44E, and the second projection system 45B, and the reflected light from the wafer surface is For example, an image of an alignment mark on the wafer surface is formed on the image sensor 90 via the second projection system 45B, the dichroic mirror 44E, the correction lens 88, the beam splitter 87, and the imaging lens 89. Search alignment and autofocus of the wafer W2 can be performed using the information on the position and contrast of the image.

  11C is a surface conjugate with the light source 85, the condenser lens 86, and the wafer surface above the dichroic mirror 44E with respect to the defective shot exposure system 40D of FIG. 11B. A pinhole plate 91A, a condensing lens 92A, a beam splitter 87, a correction lens 92B, a condensing lens 92C, a pinhole plate 91B disposed on a plane conjugate with the wafer surface, and a photoelectric sensor 93 are provided. Yes.

  In this case, the detection light emitted from the light source 85 and passing through the pinhole of the pinhole plate 91A forms a pinhole image once in the beam splitter 87 by the condenser lens 92A, and then the correction lens 92B and the second projection system. A slit image is formed on the wafer surface via 45B. The reflected light from the wafer surface forms an image once through the second projection system 45B and the correction lens 92B, and then forms a pinhole image on the pinhole plate 91B by the condenser lens 92C. The light that has passed through is received by the photoelectric sensor 93. In this modification, since the detection signal of the photoelectric sensor 93 changes when the height of the wafer surface changes, the focus position of the wafer surface can be measured. It is also possible to calibrate the AF system 29 in FIG. 1 using the measurement result of the photoelectric sensor 93.

  Further, the missing shot exposure system 40F in FIG. 11D is different from the missing shot exposure system 40A in FIG. 9A in the reticle blind (which defines the illumination area of the exposure light ILA in the vicinity of the pattern surface of the reticle 43). (Field stop) 94 is provided. With this reticle blind 94, the shape of the illumination area on the reticle 43, and hence the exposure area on the wafer W2, can be made variable.

The present invention can be applied not only to a scanning exposure type projection exposure apparatus but also to exposure using a batch exposure type (stepper type) projection exposure apparatus. The present invention can also be applied to the case where exposure is performed with a dry exposure type exposure apparatus.
In addition, the present invention is not limited to application to a semiconductor device manufacturing process. For example, a manufacturing process of a display device such as a liquid crystal display element or a plasma display formed on a square glass plate, an imaging element, and the like. (CCD, etc.), micromachines, MEMS (Microelectromechanical Systems), thin film magnetic heads, and various chip manufacturing processes such as DNA chips. Furthermore, the present invention can also be applied to a manufacturing process when manufacturing a mask (photomask, reticle, etc.) on which a mask pattern of various devices is formed using a photolithography process.
In addition, this invention is not limited to the above-mentioned embodiment, Of course, a various structure can be taken in the range which does not deviate from the summary of this invention.

It is a figure which shows schematic structure of the exposure apparatus of the 1st Embodiment of this invention. (A) is a plan view showing the simplified stage 13 in FIG. 1, (B) is an enlarged view showing an image exposed in the exposure area 46A in FIG. 2 (A), and (C) is an exposure area in FIG. 2 (A). It is an enlarged view which shows the image exposed by 46C. (A) is a figure which shows the structure of the aerial image measurement system 55A of FIG. 2 (A), (B) is a figure which shows another example of an aerial image measurement system. (A) is a figure which shows the structural example of AF system 29 of FIG. 1, (B) is a figure which shows the image observed with the image pick-up element 79 of FIG. 4 (A). (A) is a plan view showing an example of a shot map of wafer W2 in FIG. 1, and (B) is an enlarged view showing a pattern exposed by projection optical system PL in FIG. It is a top view which shows the operation | movement which exposes the chip shot of the wafer W2 by the exposure area | region 46A. It is a top view which shows the operation | movement which exposes the chip shot of the wafer W2 by the exposure area | region 46C. 3 is a flowchart showing an example of an exposure operation of the exposure apparatus 100 of FIG. (A) is a perspective view showing a chipped shot exposure unit 150A according to the second embodiment of the present invention, (B) is a diagram showing an example of detection light of the AF system 29A in FIG. 9 (A), and (C) is detection. It is a figure which shows the state which irradiates light from the outer side of the edge of a wafer. It is a figure which shows the lack shot exposure unit 150B of the 3rd Embodiment of this invention. (A), (B), (C), (D) is a figure which shows the principal part of the modification of a missing shot exposure system, respectively.

Explanation of symbols

  R ... reticle, PL ... projection optical system, WST ... wafer stage, W1, W2 ... wafer, WM ... wafer mark, 13 ... simple stage, 20A ... first control system, 20B ... second control system, 26A, 26B ... alignment Sensors 28, 29 ... AF system, 40, 40A to 40F ... chip shot exposure system, 46A, 46C ... exposure area, 48A, 48B ... pre-alignment sensor (PA sensor), 100 ... exposure apparatus, 140 ... main body, 150 , 150A, 150B ... chip shot exposure unit

Claims (19)

In an exposure method for exposing a plurality of regions including different first and second regions on a substrate,
A first step of holding the substrate on a holding mechanism and measuring first measurement information including position information of the substrate in at least one of a direction along the surface of the substrate and a normal direction of the surface;
A second step of exposing the second region on the substrate based on the first measurement information;
A third step of placing the substrate on a movable substrate holding body movable in a two-dimensional plane;
A fourth step of exposing the first region on the substrate by driving the substrate holding movable body using the first measurement information;
An exposure method comprising: The fourth step includes
Using the first measurement information, the second information of the substrate including at least one of position information of a plurality of marks formed on the substrate and position information of the substrate in a normal direction of the surface of the substrate A process of measuring measurement information;
The exposure method according to claim 1, further comprising a step of driving the substrate holding movable body based on the second measurement information.   3. The exposure method according to claim 1, wherein when exposing the second region on the substrate, the optical system for exposure and the substrate are relatively scanned. 4. Exposing the first and second patterns to the first and second regions on the substrate, respectively;
4. The exposure method according to claim 1, wherein a line width of the second pattern is 5 to 20 times a minimum line width of the first pattern. 5.   The wavelength width of the second exposure light used for exposure of the second region on the substrate is wider than the wavelength width of the first exposure light used for exposure of the first region on the substrate. The exposure method according to claim 4, wherein the exposure method is characterized in that:   6. The exposure method according to claim 1, wherein the first step includes a step of detecting positional information of the substrate based on an outer shape reference. The second region on the substrate is a region surrounding the first region;
The first step irradiates measurement light obliquely on the substrate from the inner side to the outer side of the edge of the substrate, and receives the reflected light from the substrate, whereby the surface of the substrate is The exposure method according to any one of claims 1 to 6, further comprising a step of measuring positional information of the substrate in a normal direction. In an exposure apparatus that exposes a plurality of regions on a substrate,
A substrate holding movable body that holds the substrate and is movable in a two-dimensional plane;
A holding mechanism for holding the substrate;
A transport system for moving the substrate from the holding mechanism to the substrate holding movable body;
A first measurement device that measures first measurement information including position information of at least one of the substrate in the direction along the surface of the substrate held by the holding mechanism and the normal direction of the surface;
A first optical system for exposing a first region on the substrate held by the substrate holding movable body with a first exposure light;
A second optical system for exposing a second region different from the first region on the substrate held by the holding mechanism with a second exposure light;
With
Based on the first measurement information measured by the first measurement device, the positional relationship between the substrate and the second optical system is controlled, and the second region on the substrate is controlled by the second optical system. Exposure and
After the substrate is moved from the holding mechanism to the substrate holding movable body by the transport system, the positional relationship between the substrate and the first optical system is controlled based on the first measurement information, and the first An exposure apparatus that exposes the first region on the substrate by one optical system. Second measurement information including position information of the substrate in at least one of a direction along the surface of the substrate held by the substrate holding movable body and a normal direction of the surface based on the first measurement information. A second measuring device for measuring
The positional relationship between the substrate and the first optical system is controlled based on the second measurement information, and the first region on the substrate is exposed by the first optical system. Item 9. The exposure apparatus according to Item 8. A drive mechanism for moving the holding mechanism on a guide surface;
9. When exposing the second region on the substrate, the driving mechanism moves the holding mechanism to relatively scan the second optical system and the substrate. The exposure apparatus according to claim 9. A drive mechanism for moving the second optical system;
The second optical system is moved by the drive mechanism when the second region on the substrate is exposed, and the second optical system and the substrate are relatively scanned. An exposure apparatus according to claim 8 or 9. The first and second optical systems expose the first and second patterns to the first and second regions on the substrate, respectively.
12. The exposure apparatus according to claim 8, wherein a line width of the second pattern is 5 to 20 times a minimum line width of the first pattern.   The first measuring device detects a plurality of marks on the substrate and detects position information in a direction along at least the surface of the substrate, and position information in a normal direction of the surface of the substrate. The exposure apparatus according to any one of claims 8 to 12, further comprising a surface position detection device for measuring.   The exposure apparatus according to claim 13, wherein the first measurement device includes a detection device that detects position information of the substrate based on an outer shape reference. The second region on the substrate is a region surrounding the first region;
The first measurement device includes an irradiation system that irradiates measurement light obliquely onto the substrate from an inner side to an outer side of the edge of the substrate held by the holding mechanism, and reflected light from the substrate And a light receiving system for receiving light,
The exposure apparatus according to claim 8, wherein position information of the substrate in a normal direction of the surface of the substrate is measured. An exposure unit that is used together with an exposure main body that exposes the first area of the different first and second areas on the substrate,
A holding mechanism for holding the substrate;
A measurement device that measures measurement information including position information of the substrate in at least one of a direction along the surface of the substrate held by the holding mechanism and a normal direction of the surface;
An optical system for exposing the second region on the substrate held by the holding mechanism;
A control system for supplying the measurement information measured by the measurement device to the exposure main body;
An exposure unit comprising:   The measuring device detects a plurality of marks on the substrate and detects position information in a direction along at least the surface of the substrate, and a surface position that measures position information in the normal direction of the surface of the substrate The exposure unit according to claim 16, further comprising a detection device.   18. The exposure unit according to claim 16, further comprising a scanning mechanism that relatively scans the substrate held by the holding mechanism and the optical system. A device manufacturing method comprising:
Preparing a photosensitive substrate;
Using the exposure apparatus according to any one of claims 8 to 15 to expose a predetermined pattern on the photosensitive substrate through the first and second optical systems;
Developing the exposed photosensitive substrate, and forming a mask layer having a shape corresponding to the pattern exposed through the first and second optical systems on the surface of the photosensitive substrate;
Processing the surface of the photosensitive substrate through the mask layer;
A device manufacturing method comprising:

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