JP2008304840A - Mask protecting device, mask, exposure method, method for manufacturing device, and conveyance method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mask protecting device capable of preferably irradiating a mask with exposure light. <P>SOLUTION: The mask protecting device protects the surface of a mask to be irradiated with exposure light. The mask protecting device is equipped with frame members disposed in a first direction and a second direction orthogonal to each other and supporting a pellicle to protect the surface of the mask. At least a part of the inner face of the frame member disposed in the first direction is inclined as gradually separating from the mask surface in a direction from the inside to the outside of the frame member. The inner face of the frame member disposed in the second direction is substantially perpendicular to the mask surface. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a mask protection device, a mask, an exposure method, a device manufacturing method, and a transport method.

An exposure apparatus used in a photolithography process forms an image of a pattern on a substrate by illuminating the mask with exposure light and irradiating the substrate with exposure light through the mask. If foreign matter adheres to the surface of the mask, exposure defects such as defects in the pattern formed on the substrate may occur. Therefore, the mask is often provided with a mask protection device such as a pellicle. The following patent document discloses an example of a technique related to a mask protection device including a pellicle and a frame member that supports the pellicle.
JP 2004-258113 A

  When irradiating the mask with exposure light, there is a possibility that the mask protection device is unnecessarily irradiated with the exposure light depending on the exposure light irradiation state or the structure of the mask protection device. In that case, there is a possibility that the process using the exposure light cannot be performed satisfactorily.

  An object of this invention is to provide the mask protection apparatus which can irradiate exposure light to a mask favorably, and the mask provided with the mask protection apparatus. Another object of the present invention is to provide an exposure method capable of satisfactorily exposing a substrate using the mask, and a device manufacturing method using the exposure method. Another object of the present invention is to provide a transport method that can transport a mask satisfactorily.

  In order to solve the above-described problems, the following configurations corresponding to the respective drawings shown in the embodiments are adopted as each aspect illustrating the present invention. However, the reference numerals with parentheses attached to each element are merely examples of the element and do not limit each element.

  According to a first aspect illustrating the present invention, there is provided a mask protection device for protecting the surface (50A) of a mask (M) irradiated with exposure light (EL), in a first direction (Y) perpendicular to the mask (M). A frame disposed in the second direction (X) and having a frame member (70) for supporting a pellicle (75) for protecting the surface (50A) of the mask (M) and disposed in the first direction (Y) At least a part of the inner surface (71A) of the members (70, 71) is inclined so as to gradually move away from the surface (50A) of the mask (M) in the direction from the inner side to the outer side of the frame member (70). And the inner surface (72A) of the frame member (70, 72) arranged in the second direction (X) is substantially perpendicular to the surface (50A) of the mask (M). ) Is provided.

  According to the first aspect exemplifying the present invention, the exposure light can be favorably irradiated onto the mask.

  According to a second aspect illustrating the present invention, there is provided a mask protection device for protecting the surface (50A) of a mask (M) irradiated with exposure light (EL) while moving in a first direction (Y). And an inner surface of the frame members (70, 71) arranged in the first direction (Y), including a frame member (70) for supporting the pellicle (75) for protecting the surface (50A) of the mask (M) At least a part of (71A) is inclined so as to gradually move away from the surface (50A) of the mask (M) in the direction from the inner side to the outer side of the frame member (70), and the first direction (Y). An inner surface (72A) of the frame member (70, 72) arranged in the second orthogonal direction (X) has a mask protection device (7) that is substantially perpendicular to the surface (50A) of the mask (M). ) Is provided.

  According to the 2nd aspect which illustrates this invention, exposure light can be irradiated to a mask favorably.

  According to a third aspect of the present invention, a mask (M) provided with the mask protection device (7) of the first aspect or the second aspect is provided.

  According to the 3rd aspect which illustrates this invention, exposure light can be irradiated to a mask favorably.

  According to the fourth aspect illustrating the present invention, the mask (M) of the third aspect is illuminated with exposure light (EL) while moving in the first direction (Y), and the mask (M) is interposed. Exposing the substrate (P) with the exposed exposure light (EL).

  According to the 4th aspect which illustrates this invention, a board | substrate can be exposed favorably.

  According to a fifth aspect exemplifying the present invention, a device manufacture comprising: exposing a substrate (P) using the exposure method of the fourth aspect; and developing the exposed substrate (P). A method is provided.

  According to the 5th aspect which illustrates this invention, a device can be manufactured using the exposure method which can expose a board | substrate favorably.

  According to a sixth aspect exemplifying the present invention, there is provided a method for transporting a mask (M) irradiated with exposure light (EL), wherein the mask (M) is a mask protection device (7) according to the first aspect. And a transport method for transporting the mask (M) while supporting a predetermined area of the mask (M) outside the frame members (70, 72) in the second direction (X).

  According to the 6th aspect which illustrates this invention, a mask can be conveyed favorable.

  According to a seventh aspect exemplifying the present invention, there is provided a method for transporting a mask (M) irradiated with exposure light (EL), wherein the mask (M) is a mask protection device (7) according to the second aspect. And a transport method for transporting the mask (M) while supporting a predetermined area of the mask (M) outside the frame members (70, 72) in the second direction (X).

  According to the 7th aspect which illustrates this invention, a mask can be conveyed favorable.

  According to the present invention, exposure light can be satisfactorily irradiated on the mask. Moreover, according to this invention, a board | substrate can be exposed favorably and a favorable device can be manufactured. Moreover, according to this invention, a mask can be conveyed favorable.

  Hereinafter, embodiments of the present invention will be exemplarily described with reference to the drawings, but the present invention is not limited thereto. In the following description, an XYZ orthogonal coordinate system is set, and the positional relationship of each member will be described with reference to this XYZ orthogonal coordinate system. A predetermined direction in the horizontal plane is defined as the X-axis direction, a direction orthogonal to the X-axis direction in the horizontal plane is defined as the Y-axis direction, and a direction orthogonal to the X-axis direction and the Y-axis direction (that is, the vertical direction) is defined as the Z-axis direction. Further, the rotation (inclination) directions around the X axis, Y axis, and Z axis are the θX, θY, and θZ directions, respectively.

  1 is a perspective view of the mask M according to the present embodiment as viewed from the −Z side, FIG. 2A is a side sectional view parallel to the YZ plane showing the mask M, and FIG. FIG. 3 is an enlarged view of a part of FIG. 1.

  The mask M includes a plate-like substrate 50 and a pattern (device pattern) PA formed on the substrate 50. In the present embodiment, the outer shape of the mask M in the XY plane is substantially rectangular, and the size in the Y-axis direction is larger than the size in the X-axis direction.

  The pattern PA is formed on one surface 50 </ b> A of the substrate 50. In the following description, one surface 50A of the substrate 50 on which the pattern PA is formed is appropriately referred to as a surface 50A of the mask M. 1 to 3, the surface 50A of the mask M is substantially parallel to the XY plane.

  As will be described later, the mask M is used for substrate exposure processing, and the surface 50A of the mask M is irradiated with exposure light. The mask M of the present embodiment is a reflection type, and the exposure light is irradiated to the surface 50A of the mask M.

  The surface 50A of the mask M includes a pattern formation region 51 in which a pattern PA is formed, a light shielding band 52 disposed around the pattern formation region 51, and a first alignment mark formation region 53 in which a first alignment mark 61 is formed. And a second alignment mark formation region 54 in which the second alignment mark 62 is formed.

  The mask M includes a protection device 7 for protecting the surface 50A of the mask M. The protection device 7 includes a pellicle 75 for protecting at least a part of the surface 50 </ b> A of the mask M, and a frame member 70 that supports the pellicle 75.

  The frame member 70 is connected to the surface 50A of the mask M. The frame member 70 is disposed around the pattern formation region 51 and the light shielding band 52. The outer shape of the frame member 70 in the XY plane is substantially rectangular along the outer shape of the mask M, and the size in the Y-axis direction is larger than the size in the X-axis direction.

  The frame member 70 has a first portion 71 disposed on both sides in the Y-axis direction with respect to the pattern formation region 51 and a second portion 72 disposed on both sides in the X-axis direction with respect to the pattern formation region 51. The first portion 71 is formed so as to extend in the X-axis direction, and the second portion 72 is formed so as to extend in the Y-axis direction. The size (length) of the second portion 72 in the Y-axis direction is longer than the size (length) of the first portion 71 in the X-axis direction.

  The inner side surface 71A of the first portion 71 of the frame member 70 disposed in the Y-axis direction with respect to the pattern formation region 51 gradually separates from the surface 50A of the mask M in the direction from the inner side to the outer side of the frame member 70. It is inclined to. In other words, the inner side surface 71A of the first portion 71 is inclined so as to gradually move away from the surface 50A of the mask M in the direction from the center of the surface 50A of the mask M surrounded by the frame member 70 to the outside. . In the present embodiment, the outer surface 71B of the first portion 71 is inclined along the inner surface 71A.

  The inner side surface 72A of the second portion 72 of the frame member 70 disposed in the X-axis direction with respect to the pattern formation region 51 is substantially perpendicular to the surface 50A of the mask M. In the present embodiment, the outer surface 72B of the second portion 72 is substantially perpendicular to the surface 50A of the mask M along the inner surface 72A.

  The pellicle 75 is supported by the frame member 70. The pellicle 75 is disposed so as to face the surface 50A of the mask M. A predetermined gap is formed between the surface 50 </ b> A of the mask M and the pellicle 75 supported by the frame member 70.

  The first alignment mark formation region 53 is disposed inside the frame member 70. The first alignment mark formation region 53 is arranged in the Y axis direction with respect to the pattern formation region 51.

  The first alignment mark formation region 53 is disposed at a predetermined position on the surface 50 </ b> A of the mask M between the inner surface 71 </ b> A of the first portion 71 and the pattern formation region 51. In the present embodiment, the first alignment mark formation region 53 is a predetermined position on the surface 50A of the mask M between the inner side surface 71A of the first portion 71 and the light shielding band 52 disposed around the pattern formation region 51. Is arranged. In the present embodiment, the first alignment mark formation regions 53 are arranged at four locations on the surface 50A of the mask M. In the present embodiment, the first alignment mark formation region 53 is disposed near each of the four corners of the pattern formation region 51.

  The second alignment mark formation region 54 is disposed outside the frame member 70. The second alignment mark formation region 54 is arranged in the X-axis direction with respect to the pattern formation region 51.

  The second alignment mark formation region 54 is disposed at a predetermined position on the surface 50A of the mask M outside the second portion 72 in the X-axis direction. In the present embodiment, the second alignment mark formation region 54 is disposed at a predetermined position on the surface 50 </ b> A of the mask M in the vicinity of the outer surface 72 </ b> B of the second portion 72. In the present embodiment, the second alignment mark formation regions 54 are arranged at two locations on the surface 50A of the mask M. In the present embodiment, the second alignment mark formation region 54 is arranged at the center of the mask M in the Y-axis direction on the surface 50A of the mask M on both sides in the X-axis direction with respect to the frame member 70.

  FIG. 4 is a schematic block diagram that shows an example of the exposure apparatus EX according to the present embodiment. In FIG. 4, an exposure apparatus EX is held by a mask stage 1 that is movable while holding a mask M, a substrate stage 2 that is movable while holding a substrate P for forming a device, and the mask stage 1. The illumination optical system IL that illuminates the mask M with the exposure light EL, the projection optical system PL that projects an image of the pattern of the mask M illuminated with the exposure light EL onto the substrate P, and the positions of the mask stage 1 and the substrate stage 2 An interferometer system 3 including laser interferometers 3M and 3P for measuring information and a control device 5 for controlling the operation of the entire exposure apparatus EX are provided.

  The exposure apparatus EX of the present embodiment is an EUV exposure apparatus that exposes the substrate P with extreme ultraviolet light. Extreme ultraviolet light is an electromagnetic wave in a soft X-ray region having a wavelength of about 5 to 50 nm, for example. In the following description, extreme ultraviolet light is appropriately referred to as EUV light.

  The exposure apparatus EX includes a chamber apparatus 6 having a vacuum system that adjusts at least a predetermined space through which the exposure light EL passes to a vacuum state. Thereby, attenuation of exposure light (EUV light) EL is suppressed.

  The substrate P includes a substrate in which a film such as a photosensitive material (resist) is formed on a base material such as a semiconductor wafer. The mask M is a reflective mask having a multilayer film capable of reflecting EUV light. The base material 50 of the mask M is formed of an ultra low thermal expansion material. The multilayer film is formed on the substrate 50. The multilayer film includes, for example, a Mo / Si multilayer film and a Mo / Be multilayer film. The pattern PA is formed by an absorber formed on the multilayer film. The absorber includes, for example, Cr, TaN and the like. The exposure apparatus EX illuminates the surface 50A of the mask M on which the pattern PA is formed by the multilayer film and the absorber with the exposure light (EUV light) EL, and exposes the substrate P with the exposure light EL reflected by the mask M.

  The exposure apparatus EX of the present embodiment is a scanning exposure apparatus (so-called scanning stepper) that projects an image of the pattern of the mask M onto the substrate P while synchronously moving the mask M and the substrate P in a predetermined scanning direction. When the substrate P is exposed, the mask M and the substrate P are moved in a predetermined scanning direction in the XY plane. In the present embodiment, the scanning direction (synchronous movement direction) of the substrate P is the Y-axis direction, and the scanning direction (synchronous movement direction) of the mask M is also the Y-axis direction. The exposure apparatus EX moves the substrate P in the Y-axis direction with respect to the projection area of the projection optical system PL and synchronizes with the movement of the substrate P in the Y-axis direction with respect to the illumination area of the illumination optical system IL. Then, the mask M is irradiated with the exposure light EL while moving the mask M in the Y-axis direction. The exposure light EL through the mask M is irradiated onto the substrate P through the projection optical system PL. Thereby, the pattern image of the mask M is projected onto the substrate P, and the substrate P is exposed with the exposure light EL.

The illumination optical system IL includes a plurality of optical elements IR _{1 to} IR ₅ and illuminates a predetermined illumination area on the mask M with exposure light EL having a uniform illuminance distribution. The optical elements IR _{1 to} IR ₅ include a multilayer mirror that includes a multilayer film capable of reflecting EUV light. The multilayer films of the optical elements IR _{1 to} IR ₅ include, for example, a Mo / Si multilayer film and a Mo / Be multilayer film. The exposure light EL illuminated by the illumination optical system IL and reflected by the surface 50A of the mask M enters the projection optical system PL from the object plane side of the projection optical system PL.

The illumination optical system IL illuminates the mask M with the exposure light EL from the light source 8. The light source 8 of the present embodiment is a laser-excited plasma light source, and includes a housing 9, a laser device 10 that emits laser light, and a supply member 11 that supplies a target material such as xenon gas into the housing 9. . The laser light emitted from the laser device 10 and condensed by the condensing optical system 12 is applied to the target material emitted from the tip of the supply member 11. The target material irradiated with the laser light is turned into plasma and generates light including EUV light (exposure light EL). The light generated at the tip of the supply member 11 is collected by the capacitor 13. The light that has passed through the capacitor 13 is incident on the optical element IR ₁ that functions as a collimator mirror disposed outside the housing 9. The light source may be a discharge plasma light source or another light source.

  While holding the mask M, the mask stage 1 is movable in six directions including the X axis, Y axis, Z axis, θX, θY, and θZ directions. In the present embodiment, the mask stage 1 holds the back surface 50B of the mask M. In the present embodiment, the mask stage 1 holds the mask M so that the surface 50A of the mask M faces the -Z side and the surface 50A of the mask M and the XY plane are substantially parallel. The mask stage 1 holds the mask M so that the first portion 71 of the protection device 7 is arranged in the Y axis direction with respect to the pattern formation region 51. Position information of the mask stage 1 (mask M) is measured by the laser interferometer 3M of the interferometer system 3. The laser interferometer 3 </ b> M uses the measurement mirror 1 </ b> R provided on the mask stage 1 to measure position information regarding the X axis, the Y axis, and the θZ direction of the mask stage 1. Further, surface position information (position information regarding the Z axis, θX, and θY) of the surface of the mask M held on the mask stage 1 is detected by a focus / leveling detection system (not shown). The control device 5 controls the position of the mask M held on the mask stage 1 based on the measurement result of the laser interferometer 3M and the detection result of the focus / leveling detection system.

  FIG. 5 is a schematic diagram showing the relationship between the exposure light EL from the illumination optical system IL and the mask M, and FIG. 6 is an enlarged view of FIG. As shown in FIGS. 5 and 6, the illumination optical system IL irradiates the surface 50A of the mask M with the exposure light EL from an oblique direction. The exposure light EL is incident on the surface 50A of the mask M from an oblique direction. The exposure light EL is incident on the surface of the mask M at a predetermined incident angle θn in the YZ plane. In the present embodiment, the incident angle θn includes an angle formed by the optical axis AX and the Z axis.

  The inclination angle θk of the inner surface 71A of the first portion 71 of the frame member 70 is a value corresponding to the incident angle θn of the exposure light EL with respect to the surface 50A of the mask M. In the present embodiment, the inclination angle θk is a value corresponding to the numerical aperture NA of the illumination optical system IL. In the present embodiment, the inclination angle θk includes an angle formed by the inner side surface 71A and the Z axis. NA = n × sin θ, where θ is the maximum angle with respect to the optical axis AX of the light ray incident on the surface 50A of the mask M, and n is the refractive index of the medium through which the exposure light EL travels. In the present embodiment, the exposure light EL travels in a vacuum and has a refractive index n = 1.

  In the present embodiment, when the exposure light EL is irradiated onto the surface 50A of the mask M inside the frame member 70, the incident angle θn is prevented so that the exposure light EL from the illumination optical system IL is not unnecessarily irradiated onto the frame member 70. Depending on the numerical aperture NA, the inner surface 71A of the first portion 71 of the frame member 70 is inclined by a predetermined angle θk. Thus, even when the exposure light EL is irradiated to a predetermined region in the vicinity of the inner side surface 71A of the first portion 71, for example, the first alignment mark formation region 53, of the surface 50A of the mask M inside the frame member 70, The first alignment mark formation region 53 can be irradiated with the exposure light EL satisfactorily.

Returning to FIG. 4, the projection optical system PL includes a plurality of optical elements PR _{1 to} PR ₄ and projects an image of the pattern of the mask M onto the substrate P at a predetermined projection magnification. The optical elements PR _{1 to} PR ₄ include a multilayer film reflecting mirror including a multilayer film capable of reflecting EUV light. The multilayer films of the optical elements PR _{1 to} PR ₄ include, for example, a Mo / Si multilayer film and a Mo / Be multilayer film. The exposure light EL that has entered the projection optical system PL from the object plane side of the projection optical system PL is emitted to the image plane side of the projection optical system PL and enters the substrate P. The pattern image of the mask M illuminated by the exposure light EL is projected onto the substrate P on which the photosensitive material film is formed via the projection optical system PL.

  The substrate stage 2 is movable in six directions, ie, the X-axis, Y-axis, Z-axis, θX, θY, and θZ directions while holding the substrate P. In the present embodiment, the substrate stage 2 holds the substrate P so that the surface of the substrate P faces the + Z side and the surface of the substrate P and the XY plane are substantially parallel. The position information of the substrate stage 2 (substrate P) is measured by the laser interferometer 3P of the interferometer system 3. The laser interferometer 3P uses the measurement mirror 2R provided on the substrate stage 2 to measure position information regarding the X axis, the Y axis, and the θZ direction of the substrate stage 2. Further, surface position information (position information regarding the Z axis, θX, and θY) of the surface of the substrate P held on the substrate stage 2 is detected by the focus / leveling detection system 4. The focus / leveling detection system 4 includes an irradiator 4A that emits detection light from a direction inclined with respect to the surface of the substrate P, and a light receiver 4B that can receive the detection light reflected by the surface of the substrate P. The surface position information on the surface of the substrate P can be detected. The control device 5 controls the position of the substrate P held on the substrate stage 2 based on the measurement result of the laser interferometer 3P and the detection result of the focus / leveling detection system 4.

  Further, the exposure apparatus EX of the present embodiment includes an off-axis first alignment system 15 that detects an alignment mark on the substrate P, a reference mark provided on the substrate stage 2, and the like. At least a part of the first alignment system 15 is disposed in the vicinity of the tip of the projection optical system PL. The first alignment system 15 of this embodiment is a broadband detection that does not expose the photosensitive film on the substrate P as disclosed in, for example, Japanese Patent Laid-Open No. 4-65603 (corresponding US Pat. No. 5,493,403). The target mark (an alignment mark on the substrate P, a reference mark on the substrate stage 2, etc.) is irradiated with light, and an image of the target mark and an index (first) formed on the light receiving surface by reflected light from the target mark An image of an index mark on an index plate provided in the alignment system 15 is imaged using an image sensor such as a CCD, and the image position is measured by image processing of these imaged signals. Alignment) type alignment system is adopted.

  Further, the exposure apparatus EX of the present embodiment includes an aerial image measurement system 20 that measures an aerial image of the projection optical system PL as disclosed in, for example, US Patent Application Publication No. 2002/0041377. Yes. In the present embodiment, at least a part of the aerial image measurement system 20 is provided on the substrate stage 2. The aerial image measurement system 20 includes a measurement member (slit plate) 23 including a light-shielding film having a slit-like opening 21 that can receive a light beam emitted from the projection optical system PL, and light reception that receives light from the measurement member 23. Device 24. The light receiving device 24 includes a light receiving optical system into which light from the measurement member 23 enters, and an optical sensor including a photoelectric conversion element that outputs an electrical signal corresponding to the light via the light receiving optical system.

  Further, the exposure apparatus EX includes a transport apparatus 30 that transports the mask M to the mask stage 1. The transfer device 30 can carry out the mask M from the mask housing portion 35 and carry (load) the mask M into the mask stage 1.

  Further, the exposure apparatus EX of the present embodiment includes a second alignment system 40 that measures the second alignment mark 62 of the mask M. The second alignment system 40 is disposed in the transport path of the transport device 30. Before the mask M is held on the mask stage 1, the second alignment mark 62 is measured by the second alignment system 40. In the present embodiment, the second alignment system 40 measures the second alignment mark 62 of the mask M supported by the transfer device 30 before being held on the mask stage 1. The control device 5 executes the alignment process of the mask M with respect to the mask stage 1 based on the measurement result of the second alignment system 40. That is, the control device 5 prealigns the mask M with respect to the mask stage 1 based on the measurement result of the second alignment system 40.

  FIG. 7 is a perspective view of the transport device 30 that transports the mask M as viewed from above, and FIG. 8 is a perspective view of the transport device 30 that transports the mask M as viewed from below. 7 and 8, the transport device 30 includes a transport member 31 that supports a predetermined position of the mask M. The transport member 31 includes a support member 32 and a fork-shaped arm member 33 supported by the support member 32. The fork-like arm member 33 has two fork portions (convex portions) 34 extending in the −Y direction in the drawing. The arm member 33 including the two fork portions 34 can be moved in six directions including an X axis, a Y axis, a Z axis, θX, θY, and θZ directions by a drive mechanism (not shown).

  In the present embodiment, the transport member 31 supports a predetermined region of the surface 50A of the mask M outside the frame member 70 (second portion 72) in the X-axis direction with the fork portion 34. The fork portion 34 supports a predetermined region on the surface 50A of the mask M outside the second alignment mark formation region 54 with respect to the frame member 70 in the X-axis direction. That is, as shown in FIG. 8, the second alignment mark formation region 54 is disposed between the second portion 72 of the frame member 70 and the fork portion 34.

  In the present embodiment, as shown in FIG. 8, a bar code for identifying the mask M in a predetermined region of the surface 50A of the mask M outside the frame member 70 (second portion 72) in the X-axis direction. An identifier area 91 including such identifiers is arranged.

  FIG. 9 is a schematic diagram showing the second alignment system 40. The second alignment system 40 includes two mark measuring devices 41 and 42 arranged along the X-axis direction. The first mark measurement device 41 measures the second alignment mark 62 of one second alignment mark formation region 54 out of the second alignment mark formation regions 54 provided at two positions of the mask M, and the second mark The measuring device 42 measures the second alignment mark 62 in the other second alignment mark formation region 54. In the present embodiment, the second alignment system 40 uses the first and second mark measuring devices 41 and 42 to perform the second alignment of each of the second alignment mark formation regions 54 provided at two locations on the mask M. The mark 62 can be measured simultaneously.

  The second alignment system 40 measures the second alignment mark 62 of the mask M in a state where a predetermined region of the outer surface 50A of the frame member 70 (second portion 72) in the X-axis direction is supported by the transport member 31. Since the second alignment mark formation region 54 is disposed between the second portion 72 of the frame member 70 and the fork portion 34, the second alignment system 40 uses the first and second mark measuring devices 41 and 42. Thus, the second alignment mark 62 can be measured satisfactorily.

  In FIG. 9, in order to make it easy to see the positional relationship between the first and second mark measuring devices 41 and 42 and the second alignment mark forming region 54, the transport member 31 is shifted in the Y-axis direction with respect to the mask M. The second alignment system 40 measures the second alignment mark 62 in the positional relationship between the transport member 31 and the mask M as shown in FIG.

  Next, an example of the operation of the exposure apparatus EX having the above-described configuration will be described with reference to the flowchart of FIG.

  The mask M is unloaded from the mask housing portion 35 by the transport device 30 (step S1). When carrying out the mask M from the mask accommodating portion 35, the carrying device 30 inserts the fork portion 34 of the carrying member 31 into the mask M from the Y-axis direction, and the mask M outside the frame member 70 in the X-axis direction is inserted. A predetermined area of the surface 50A is supported.

  The control device 5 measures the second alignment mark 62 arranged on the mask M using the second alignment system 40 before the mask M is held on the mask stage 1 (step S2). The control device 5 measures the second alignment mark 62 while the mask M is being transported to the mask stage 1 by the transport device 30. As described with reference to FIG. 9 and the like, the control device 5 uses the second alignment system 40 in a state where the predetermined region of the outer surface 50A of the frame member 70 in the X-axis direction is supported by the transport member 31. The second alignment mark 62 is measured. The control device 5 pre-aligns the mask M based on the measurement result of the second alignment system 40 (step S3).

  After the processing using the second alignment mark 62 and the second alignment system 40 is completed, the control device 5 loads (loads) the mask M onto the mask stage 1 using the transport device 30. The mask stage 1 holds the carried mask M (step S4).

  Next, the control device 5 measures the first alignment mark 61 disposed on the mask M using the aerial image measurement system 20 (step S5). As shown in FIG. 11, the control device 5 controls the mask stage 1 so that the first alignment mark 61 of the mask M held on the mask stage 1 is arranged in the illumination area of the illumination optical system IL. Then, the position of the mask M is adjusted. Further, the control device 5 controls the substrate stage 2 so that the measurement member 23 of the aerial image measurement system 20 arranged on the substrate stage 2 is arranged in the projection region of the projection optical system PL. 23 position is adjusted. Then, the control device 5 illuminates the first alignment mark 61 with the exposure light EL emitted from the illumination optical system IL. The image of the first alignment mark 61 is projected onto the measurement member 23 by the projection optical system PL. The aerial image measurement system 20 measures an image of the first alignment mark 61 by the projection optical system PL using the light receiving device 24. Thus, in the present embodiment, the first alignment mark 61 is measured by the aerial image measurement system 20 via the projection optical system PL. The control device 5 measures the position information of the mask stage 1 and the substrate stage 2 using the interferometer system 3 and measures the image of the first alignment mark 61 by the projection optical system PL using the aerial image measurement system 20. To do. Thereby, the control device 5 determines the position in the XY direction of the aerial image (projected image) of the projection optical system PL in the coordinate system defined by the interferometer system 3 as the light receiving device 24 (opening 21) of the aerial image measuring system 20. ).

  As described with reference to FIGS. 5 and 6, in this embodiment, the incident angle θn and the numerical aperture NA are set so that the exposure light EL from the illumination optical system IL is not unnecessarily irradiated onto the frame member 70. Accordingly, since the inner surface 70A of the first portion 71 of the frame member 70 is inclined by the predetermined angle θk, even when the first alignment mark formation region 53 is irradiated with the exposure light EL, the first alignment mark formation is performed. The region 53 can be irradiated with the exposure light EL satisfactorily.

  In addition, the control device 5 adjusts the position of the substrate stage 2 in the XY direction, and places a reference mark (not shown) arranged on the substrate stage 2 in the detection region of the first alignment system 15. And the control apparatus 5 detects the reference | standard mark on the substrate stage 2 using the 1st alignment system 15, measuring the positional information on the substrate stage 2 using the interferometer system 3 (step S6). Thereby, the control device 5 can obtain the position information of the reference mark in the coordinate system defined by the interferometer system 3. The first alignment system 15 has a detection reference position in a coordinate system defined by the interferometer system 3, and the control device 5 determines the position of the detection reference position and the reference mark of the first alignment system 15. A relationship can be sought.

  The pattern PA on the mask M and the first alignment mark 61 are formed in a predetermined positional relationship, and the positional relationship is known. The positional relationship between the opening 21 (light receiving device 24) and the reference mark on the substrate stage 2 is also known. The control device 5 determines the positional relationship between the detection reference position of the first alignment system 15 and the reference mark on the substrate stage 2 obtained in step S6, and the projection position of the aerial image of the projection optical system PL obtained in step S5. Of the first alignment system 15 in the coordinate system defined by the interferometer system 3 based on the positional relationship between the first and second apertures 21 and the known positional relationship between the aperture 21 and the reference mark on the substrate stage 2. Baseline information that is the positional relationship between the detection reference position and the projection position of the aerial image of the projection optical system PL is derived (step S7).

  Next, the control device 5 starts an alignment process for the substrate P held on the substrate stage 2. The control device 5 uses the first alignment system 15 to start processing for detecting an alignment mark (not shown) on the substrate P (step S8). A plurality of shot areas, which are exposure target areas, are arranged on the substrate P, and alignment marks are arranged on the substrate P so as to correspond to the plurality of shot areas. The control device 5 moves the substrate stage 2 in the XY directions, and sequentially arranges a plurality of alignment marks provided so as to correspond to each shot region on the substrate P in the detection region of the first alignment system 15. Then, the control device 5 sequentially detects a plurality of alignment marks on the substrate P using the first alignment system 15 while measuring the position information of the substrate stage 2 using the interferometer system 3. Thereby, the control device 5 can obtain the position information of the alignment mark on the substrate P within the coordinate system defined by the interferometer system 3. Further, the control device 5 can obtain the positional relationship between the detection reference position of the first alignment system 15 and the alignment mark on the substrate P.

  Next, the control device 5 calculates the position information of each of the plurality of shot areas on the substrate P with respect to the detection reference position of the first alignment system 15 based on the position information of each alignment mark on the substrate P by arithmetic processing. Obtained (step S9). When the position information of each of the plurality of shot areas on the substrate P is obtained by arithmetic processing, a so-called EGA (enhanced global alignment) method as disclosed in, for example, Japanese Patent Laid-Open No. 61-44429 is used. It can be obtained using. Thereby, the control device 5 can determine the position coordinates (array coordinates) of each of the plurality of shot areas provided on the substrate P. Further, the control device 5 can obtain the positional relationship between the detection reference position of the first alignment system 15 and each shot area on the substrate P from the output of the interferometer system 3.

  The control device 5 has a positional relationship between the detection reference position of the first alignment system 15 and each shot area on the substrate P in the coordinate system defined by the interferometer system 3 (array information of the shot area with respect to the detection reference position). , And based on the positional relationship between the detection reference position of the first alignment system 15 and the projection position of the image of the pattern of the mask M within the coordinate system defined by the interferometer system 3. The relationship between each shot area on the substrate P in the coordinate system and the projection position of the pattern image of the mask M is derived.

  Then, the control device 5 controls the position of the substrate P held on the substrate stage 2 based on the positional relationship between each shot area on the substrate P and the projection position of the pattern image of the mask M, and the substrate P The plurality of upper shot areas are sequentially exposed (step S10).

  As described above, according to the present embodiment, the inner side surface 71A of the first portion 71 of the frame member 70 is inclined according to the incident angle θk of the exposure light EL, the numerical aperture NA of the illumination optical system IL, and the like. Therefore, unnecessary irradiation of the exposure light EL to the frame member 70 can be suppressed, and the first alignment mark 61 arranged in the first alignment mark formation region 53 can be irradiated with the exposure light EL satisfactorily. Therefore, the measurement process can be executed satisfactorily. And the board | substrate P can be favorably exposed using the result of the measurement process.

  In the present embodiment, the first alignment mark 61 is arranged in the Y-axis direction (scanning direction) with respect to the pattern formation region 51. The first alignment mark 61 is closer to the optical axis of the projection optical system PL when arranged in the Y-axis direction (scanning direction) than when arranged in the X-axis direction (non-scanning direction) with respect to the pattern formation region 51. The first alignment mark 61 can be irradiated with the exposure light EL in a state of being disposed at the position. Thereby, for example, an image of the first alignment mark 61 in which the occurrence of aberration is suppressed can be projected. Therefore, the aerial image measurement system 7 can measure the first alignment mark 61 with high accuracy.

  In the present embodiment, the synergistic effect of inclining the inner side surface 71A of the frame member 70 in the Y-axis direction and arranging the first alignment mark 61 in the Y-axis direction causes the first alignment mark 61 to The position information, and thus the position information of the pattern PA can be obtained with high accuracy, and the substrate P can be exposed satisfactorily.

  In the present embodiment, since the inner surface 72A and the outer surface 72B of the second portion 72 are substantially perpendicular to the surface of the mask M, the space of the surface 50A of the mask M outside the frame member 70 in the X-axis direction is increased. Secured. Therefore, the surface 50 </ b> A of the mask M outside the frame member 70 in the X-axis direction can be favorably supported by the transport member 31. Further, since the space of the surface 50A of the mask M outside the frame member 70 in the X-axis direction is secured, the surface 50A is supported by the transport member 31 even when the second alignment mark 62 is arranged on the surface 50A. In this state, the second alignment mark 62 can be satisfactorily measured by the second alignment system 40.

  Further, by arranging the second alignment mark 62 on the surface 50A of the mask M outside the frame member 70 in the X-axis direction, the first and second mark measuring devices 41 and 42 are arranged along the X-axis direction. The second alignment marks 62 in the second alignment mark formation regions 54 at the two positions of the mask M moved in the Y-axis direction by the transport member 31 are respectively connected to the first mark measuring device 41 and the second mark measuring device 42. Can be used simultaneously. In addition, by arranging the first and second mark measuring devices 41 and 42 along the X-axis direction so as to correspond to the two second alignment mark formation regions 54, the region occupied by the second alignment system 40 ( Space) can be reduced, and the apparatus can be miniaturized.

  In the present embodiment, the case where the entire inner surface 71A of the first portion 71 is inclined has been described as an example, but the first alignment mark forming region, for example, of the inner surface 71A of the first portion 71 is described. Only a part of the region in the vicinity of 53 may be inclined, and the other region may be perpendicular to the surface 50A of the mask M.

  In the present embodiment, the case where the inner side surface 71A of the frame member 70 (first portion 71) is a flat slope has been described as an example. However, for example, as shown in FIG. Good. Further, in order to satisfactorily irradiate the exposure light EL to the first alignment mark formation region 53, a notch 90 is formed in a part of the frame member 70 in the vicinity of the first alignment mark formation region 53 as shown in FIG. It may be formed.

  As the substrate P in the above-described embodiment, not only a semiconductor wafer for manufacturing a semiconductor device but also a glass substrate for a display device, a ceramic wafer for a thin film magnetic head, or an original mask (reticle) used in an exposure apparatus ( Synthetic quartz, silicon wafer) or the like is applied.

  As the exposure apparatus EX, in addition to the step-and-scan type scanning exposure apparatus (scanning stepper) that scans and exposes the pattern of the mask M by moving the mask M and the substrate P synchronously, the mask M and the substrate P Can be applied to a step-and-repeat type projection exposure apparatus (stepper) in which the pattern of the mask M is collectively exposed while the substrate P is stationary and the substrate P is sequentially moved stepwise.

  Furthermore, in the step-and-repeat exposure, after the reduced image of the first pattern is transferred onto the substrate P using the projection optical system while the first pattern and the substrate P are substantially stationary, the second pattern With the projection optical system, the reduced image of the second pattern may be partially overlapped with the first pattern and collectively exposed on the substrate P (stitch type batch exposure apparatus). ). Further, the stitch type exposure apparatus can be applied to a step-and-stitch type exposure apparatus in which at least two patterns are partially transferred on the substrate P, and the substrate P is sequentially moved.

  Further, as disclosed in, for example, US Pat. No. 6,611,316, two mask patterns are synthesized on a substrate through a projection optical system, and one scanning exposure is performed on one substrate. The present invention can also be applied to an exposure apparatus that performs double exposure of shot areas almost simultaneously.

  Further, the present invention relates to US Pat. No. 6,341,007, US Pat. No. 6,400,441, US Pat. No. 6,549,269, US Pat. No. 6,590,634, US Pat. No. 6,208,407. The present invention is also applicable to a twin stage type exposure apparatus having a plurality of substrate stages as disclosed in US Pat. No. 6,262,796.

  Further, as disclosed in, for example, Japanese Patent Laid-Open No. 11-135400 (corresponding to International Publication No. 1999/23692), US Pat. No. 6,897,963, etc., a substrate stage for holding the substrate and a reference mark are provided. The present invention can also be applied to an exposure apparatus that includes a formed reference member and / or a measurement stage on which various photoelectric sensors are mounted. The present invention can also be applied to an exposure apparatus that includes a plurality of substrate stages and measurement stages.

  The type of exposure apparatus EX is not limited to an exposure apparatus for manufacturing a semiconductor element that exposes a semiconductor element pattern onto a substrate P, but an exposure apparatus for manufacturing a liquid crystal display element or a display, a thin film magnetic head, an image sensor (CCD). In addition, the present invention can be widely applied to an exposure apparatus for manufacturing a micromachine, MEMS, DNA chip, reticle, mask, or the like.

  As described above, the exposure apparatus EX according to the embodiment of the present application maintains various mechanical subsystems including the respective constituent elements recited in the claims of the present application so as to maintain predetermined mechanical accuracy, electrical accuracy, and optical accuracy. Manufactured by assembling. In order to ensure these various accuracies, before and after assembly, various optical systems are adjusted to achieve optical accuracy, various mechanical systems are adjusted to achieve mechanical accuracy, and various electrical systems are Adjustments are made to achieve electrical accuracy. The assembly process from the various subsystems to the exposure apparatus includes mechanical connection, electrical circuit wiring connection, pneumatic circuit piping connection, and the like between the various subsystems. Needless to say, there is an assembly process for each subsystem before the assembly process from the various subsystems to the exposure apparatus. When the assembly process of the various subsystems to the exposure apparatus is completed, comprehensive adjustment is performed to ensure various accuracies as the entire exposure apparatus. The exposure apparatus is preferably manufactured in a clean room where the temperature, cleanliness, etc. are controlled.

  As shown in FIG. 14, a microdevice such as a semiconductor device includes a step 201 for designing a function / performance of the microdevice, a step 202 for producing a mask (reticle) based on the design step, and a substrate as a base material of the device. Manufacturing step 203, substrate processing step 204 including exposing the substrate with exposure light through a mask and developing the exposed substrate according to the above-described embodiment, device assembly step (dicing process, bonding process, (Including a processing process such as a packaging process) 205, an inspection step 206, and the like.

  As long as it is permitted by law, the disclosure of all published publications and US patents related to the exposure apparatus and the like cited in the above-described embodiments and modifications are incorporated herein by reference.

  Although the embodiments of the present invention have been described as described above, the present invention can be used by appropriately combining all the above-described constituent elements, and some constituent elements may not be used.

It is a perspective view which shows an example of the mask provided with the protective device. 2A is a side cross-sectional view parallel to the YZ plane showing the mask provided with the protection device, and FIG. 2B is a side cross-sectional view parallel to the XZ plane showing the mask provided with the protection device. It is the figure which expanded a part of FIG. It is a schematic block diagram which shows an example of exposure apparatus. It is a schematic diagram which shows the relationship between the exposure light from an illumination optical system, and a mask. FIG. 6 is an enlarged view of a part of FIG. 5. It is the perspective view which looked at the conveying apparatus which conveys a mask from the upper side. It is the perspective view which looked at the conveying apparatus which conveys a mask from the lower side. It is a schematic diagram which shows a 2nd alignment system. It is a flowchart figure which shows an example of operation | movement of exposure apparatus. It is a figure which shows an example of operation | movement of exposure apparatus. It is side sectional drawing which shows an example of the mask provided with the protective device. It is a perspective view which shows an example of the mask provided with the protective device. It is a flowchart figure which shows an example of the manufacturing process of a microdevice.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Mask stage, 2 ... Substrate stage, 7 ... Protection apparatus, 15 ... 1st alignment system, 20 ... Aerial image measurement system, 30 ... Conveyance apparatus, 31 ... Conveyance member, 40 ... 2nd alignment system, 50 ... Base material , 50A ... front surface, 50B ... back surface, 51 ... pattern formation region, 52 ... light shielding band, 53 ... first alignment mark formation region, 54 ... second alignment mark formation region, 61 ... first alignment mark, 62 ... second alignment Mark: 70: Frame member 71: First part 71A: Inner surface 71B: Outer surface 72: Second part 72A: Inner surface 72B: Outer surface 75: Pellicle EL: Exposure light EX Exposure apparatus, IL ... illumination optical system, M ... mask, P ... substrate, PL ... projection optical system

Claims (14)

A mask protection device for protecting the surface of a mask irradiated with exposure light,
A frame member arranged in a first direction and a second direction perpendicular to each other and supporting a pellicle for protecting the surface of the mask;
At least a part of the inner surface of the frame member arranged in the first direction is inclined so as to gradually move away from the surface of the mask in a direction from the inner side to the outer side of the frame member;
The mask protection device, wherein an inner surface of the frame member arranged in the second direction is substantially perpendicular to a surface of the mask. A mask protection device for protecting the surface of a mask irradiated with exposure light while moving in a first direction,
A frame member for supporting a pellicle for protecting the surface of the mask;
At least a part of the inner surface of the frame member arranged in the first direction is inclined so as to gradually move away from the surface of the mask in a direction from the inner side to the outer side of the frame member;
The mask protection device, wherein an inner surface of the frame member arranged in a second direction orthogonal to the first direction is substantially perpendicular to a surface of the mask. The mask is a reflection type, and the exposure light is incident on the surface of the mask from an oblique direction,
The mask protection device according to claim 1, wherein an inclination angle of the inclined portion is a value corresponding to an incident angle of the exposure light with respect to a surface of the mask. The mask is a reflection type, and the exposure light is incident on the surface of the mask from an illumination optical system,
The mask protection device according to claim 1, wherein an inclination angle of the inclined portion is a value corresponding to a numerical aperture of the illumination optical system.   The mask provided with the mask protection apparatus as described in any one of Claims 1-4. The surface includes a pattern formation region in which a pattern is formed,
The mask according to claim 5, further comprising a first alignment mark on the surface between the inclined portion and the pattern formation region. An image of the pattern is projected by a projection optical system,
The mask according to claim 6, wherein the first alignment mark is measured through the projection optical system.   The mask according to claim 5, further comprising a second alignment mark on the outer side of the frame member in the second direction. The exposure light is irradiated while being held by the mask holding member,
The mask according to claim 8, wherein the second alignment mark is measured before being held by the mask holding member.   The mask according to claim 9, wherein the second alignment mark is measured in a state where an outer region of the frame member in the second direction is supported by a transport member. Illuminating with exposure light while moving the mask according to any one of claims 5 to 10 in a first direction;
Exposing the substrate with exposure light through the mask. Exposing the substrate using the exposure method according to claim 11;
Developing the exposed substrate. A device manufacturing method comprising: A method of transporting a mask irradiated with exposure light,
The transport method for transporting the mask, comprising the mask protection device according to claim 1, wherein the mask transports the mask while supporting a predetermined region of the mask outside the frame member in the second direction. A method of transporting a mask irradiated with exposure light,
The transport method of transporting the mask while supporting the predetermined area of the mask outside the frame member in the second direction, wherein the mask includes the mask protection device according to claim 2.

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