JP5537466B2 - Exposure equipment - Google Patents

Description

  The present invention relates to an exposure apparatus that exposes a substrate.

  For example, the present invention relates to an apparatus for manufacturing a liquid crystal display panel, and more particularly to a so-called proximity exposure apparatus that exposes a pattern drawn on a mask close to a glass substrate.

  Manufacturing of TFT (Thin Film Transistor) substrates, color filter substrates, plasma display panel substrates, organic EL (Electroluminescence) display panel substrates, etc. for liquid crystal display devices used as display panels is performed using an exposure device. This is performed by forming a pattern on the substrate by lithography.

  In general, an exposure apparatus includes a chuck that holds a substrate by vacuum suction, and performs exposure by irradiating the surface of the substrate held by the chuck with light transmitted through a photomask.

  Conventionally, there are chucks having a flat substrate holding surface and those having a plurality of pin-shaped convex portions on the substrate holding surface.

  In the latter, the substrate is supported at a plurality of points by pin-shaped convex portions, and the space between the portion other than the pin-shaped convex portions and the substrate is evacuated to hold the substrate by vacuum suction.

  In such a chuck, in order to vacuum-suck a large substrate evenly, the space between the substrate and the portion other than the pin-shaped convex portion and the substrate is divided into a plurality of vacuum compartments for evacuation. For this reason, a bank (line) for forming a plurality of vacuum sections has been provided on the substrate holding surface.

  The substrate is normally mounted on the chuck through a plurality of push-up pins provided on the chuck. The push-up pin rises from the surface of the chuck, receives the substrate from a handling arm such as a robot, and then descends again to place the substrate on the surface of the chuck.

  The exposure apparatus is required to reduce the tact time in order to improve the mass production performance as well as to reduce the exposure failure.

  In order to shorten the tact time, it is effective to increase the lowering and raising speeds of the push-up pins, to quickly place the substrate on the chuck, and to remove it quickly after exposure.

  However, when the pin descending speed is increased and the substrate is brought closer to the chuck, the air between the substrate and the chuck does not escape completely, the air remains in the central portion of the substrate and the chuck, and the central portion of the substrate swells, The phenomenon that flatness is impaired occurs.

  And the higher this speed, the more obvious the phenomenon that the air is trapped and the central part swells greatly.

  For this reason, in order to reduce the tact time of the exposure apparatus, it is necessary to effectively exhaust the air trapped between the substrate and the chuck when the substrate is mounted on the chuck.

  As a conventional technique, a groove is formed in the non-vacuum section of the chuck surface from the center of the chuck to both the left and right and upper and lower ends, and an air hole extending from the chuck surface side (substrate mounting side) to the back surface (back surface) is formed in this groove. A chuck structure has been proposed in which air trapped in the substrate and the chuck is discharged to the side surface and back surface of the chuck through the grooves and air holes (Patent Document 1).

  In addition, when the substrate is loaded (loaded) on the chuck, the XY stage moves stepwise to move the substrate under the mask. Next, the mask retracted in the height direction (Z direction) so as not to contact the substrate is moved and positioned to a height (gap) of several hundred μm from the substrate surface (here, a narrow gap is formed) Called). After performing exposure (proximity exposure) with the mask close to the substrate, the mask is moved away from the substrate and moved to the retracted position (narrow gap release). Then, the position of the substrate is moved stepwise in the XY directions, and exposure is performed on an unexposed location on the substrate in the above procedure. Such an operation is called a shot. By repeating the shot, the entire substrate is exposed. When the exposure is completed, the chuck returns to the position where the substrate is mounted, unloads the substrate from the chuck, and loads (loads) the new substrate. After the substrate is mounted on the chuck and exposed, in order to speed up the operation of lowering the substrate and increase the throughput, two chucks are provided, while another chuck is exposed while one chuck is exposed. A method for improving throughput by mounting a substrate, making the substrate constant temperature, and moving the substrate to an exposure position has been proposed (Patent Document 2).

  In addition, in the proximity exposure method and apparatus, in order to make the light intensity variation generated on the substrate due to Fresnel diffraction uniform, the control device moves the substrate and the mask in the thickness direction or in the extending direction. There has also been proposed an apparatus that performs exposure while performing the above (Patent Document 3).

  As described above, in the prior art, in order to improve the throughput of the apparatus, two chucks are provided so that the temperature of the substrate is constant and the movement time to the exposure position is shortened, and the substrate is mounted on the chuck at high speed ( In order to make the light intensity variation uniform in a load exposure method or a proximity exposure apparatus, an idea of moving the mask and the substrate in the thickness direction or in the extending direction has been proposed.

  However, nothing is disclosed about speeding up when forming a narrow gap in which the mask is close to the substrate, and there is no description suggesting or motivating it.

JP 2007-180125 A Japanese Patent No. 4020261 JP-A-11-204394

  The problem to be solved by the present invention is to increase the speed of narrow gap formation for the purpose of improving throughput.

  Hereinafter, although the subject of the present invention is explained in an easy-to-understand manner, the present invention is not limited to the following description.

  In order to improve the throughput, it is essential to bring the mask close to the substrate at a high speed and to quickly suppress the deformation of the mask within the allowable range of exposure accuracy.

  On the other hand, when the movement speed of the mask is increased, the gap between the mask and the substrate is narrow, so that the air between the two becomes difficult to be discharged due to the shearing force due to the viscosity of the air, resulting in an increase in the air pressure. Therefore, there is a possibility that the mask is deformed by the pressure.

  The mask is held around the mask by a mask holder having a rectangular window frame shape. The mask holder is made of metal and has high rigidity, but since the mask is made of quartz, the high-pressure air generated between the mask and the substrate deforms the mask, and the mask is deformed until the air is released. It will be in the state as it is.

  When a flat plate like a mask gets close to a flat plate like a substrate, the air between them becomes difficult to escape from the gap between them, the air pressure between them rises, and the phenomenon that both get hard to approach is a squeeze effect Are known. Here, even if the mask holder is brought close to the air pressure between the mask and the substrate, the mask holder is close to the substrate, but the essential mask is deformed by the air pressure, and the high-pressure air escapes. It takes time to become flat, and there may be a problem that exposure cannot be performed during that time.

  This becomes more prominent as the gap formation speed of the mask is increased. Moreover, it becomes more apparent as the mask size increases. In recent years, with the increase in size of liquid crystal televisions, the mask size has increased, and this problem tends to become apparent. In addition, the squeeze effect becomes more obvious as the gap becomes smaller.

  Furthermore, due to the high definition accompanying the increase in the size of TV screens, the accuracy of exposure using a mask is required to be higher than ever, and the gap interval is set to achieve high-precision exposure. It tends to be narrowed.

  As described above, in order to improve the throughput, it is necessary to improve the gap formation speed of the mask. However, the higher the speed, the higher the air pressure between the mask and the substrate, and the more the mask is deformed. There is a problem that induced and trapped air escapes, mask deformation disappears, and there is a time until exposure is possible. This problem may become apparent as the mask size increases, making it difficult for the air between the two to escape.

  Even if the speed of narrow gap formation is improved, the present invention aims to improve the throughput by reducing the pressure increase of the air, resulting in a smaller amount of mask deformation, shortening the narrow gap formation time. It is.

  In the present invention, in order to realize the narrow gap formation at high speed, the mask deformation amount due to the acceleration during the narrow gap formation (medium) and the mask deformation amount due to the air pressure, which are presumed to be an impediment to the increase in the speed. Based on the comparison of the deformation amounts, it was found that the mask deformation due to the air pressure is the main factor of the mask deformation when the narrow gap is formed.

  In the present invention, the amount of deformation of the mask due to an increase in air pressure when forming a narrow gap is calculated by calculating the amount of deformation of the mask due to the increase in air pressure during movement of the mask when the mask is a rigid body and the amount of deformation of the mask due to the air pressure. I found what I needed.

  In the present invention, it has been found that the magnitude of the pressure increase when forming a narrow gap varies greatly depending on the moving speed profile of the mask.

  In the present invention, it has been found that the maximum pressure of air decreases as the moving speed of the mask is decreased.

  Here, reducing the moving speed of the mask is contrary to increasing the speed of narrow gap formation. In consideration of this point, in the present invention, even if the time from the start to the end of the movement of the mask is the same, the speed profile is asymmetric, that is, the acceleration at the time of acceleration is made larger than the acceleration at the time of deceleration. It was found that the maximum pressure can be made smaller than the maximum pressure increase value when the deceleration time is the same, that is, when the symmetric speed profile is used. In other words, if the asymmetric speed profile is set such that the point at which the mask moving speed is maximized is an earlier time (early time) than half of the total mask moving time, it has been found that the mask moving speed is smaller than the maximum pressure of the symmetric speed profile. .

  On the other hand, when the acceleration speed at the time of acceleration is reduced and the acceleration at the time of deceleration is increased, the maximum pressure is increased as compared with the case where the acceleration and the acceleration of deceleration are the same.

  Based on the above findings, the speed of narrow gap formation can be increased by moving the mask with a mask movement speed profile that has a small pressure increase during narrow gap formation, which is presumed to hinder the speed increase during narrow gap formation. , Found to improve throughput.

  In addition, a low-viscosity jetting unit that jets a gas having a viscosity lower than that of air is provided in the space between the mask and the substrate. As a result, it has been found that the air viscosity between the mask and the substrate can be reduced. As a result, the pressure rise during the formation of the narrow gap can be reduced, and it has been found that the formation of the narrow gap can be speeded up.

  Further, negative pressure means is provided in the vicinity of the outer edge of the mask and the substrate. It has been found that this negative pressure means can increase the amount and speed of air discharged from between the mask and the substrate when forming a narrow gap. As a result, the pressure rise during the formation of the narrow gap can be reduced, and it has been found that the formation of the narrow gap can be speeded up.

  And this invention has the following characteristics. The present invention may have the following features independently or may have a plurality of features at the same time.

  The present invention controls the acceleration when the mask holder moves.

  The present invention provides a chuck for mounting the substrate, a positioning unit for positioning the chuck, a mask holder for exposing a pattern to the substrate, a mask holder adjacent to the substrate, and an acceleration of the mask holder A control unit that controls the exposure, and an exposure unit that irradiates the mask with light, and the control unit uses at least a first acceleration and a second acceleration lower than the first acceleration, and The acceleration of the mask holder is controlled.

  The present invention is characterized in that the mask holder is accelerated by the first acceleration and decelerated by the second acceleration.

  The present invention is characterized in that the mask holder decelerates at the second acceleration after being accelerated at the first acceleration.

  The present invention is characterized in that the control unit changes at least one of the first acceleration and the second acceleration.

  The present invention includes a supply unit that supplies a medium having a lower viscosity than air, and the supply unit supplies the medium to the substrate.

  The present invention is characterized in that the chuck moves upward and / or downward relative to the surface of the substrate in accordance with the operation of the mask holder.

  The present invention is characterized by having a suction part for sucking an atmosphere between the chuck and the mask holder.

  The present invention has the following effects. The present invention may play the following effects independently or may play simultaneously.

  (1) The operation of the apparatus can be speeded up even when the mask is close to the substrate, that is, when a narrow gap is formed.

  (2) By using the mask speed profile that reduces the increase in the air pressure between the mask and the substrate, the maximum air pressure is reduced, thereby reducing the air resistance (reaction force) and the mask deformation. , Narrow gap formation can be accelerated.

  (3) As for the mask speed profile, “acceleration at the time of acceleration” when the mask starts to move toward the substrate, and “deceleration” when the mask is close to the substrate (when it is close to the target) are generally used. By making the acceleration at the time of acceleration larger than the acceleration at the time of deceleration rather than a symmetrical velocity profile in which the “time acceleration” is the same, the maximum pressure of the air pressure accompanying the movement of the mask can be reduced. Thereby, since the deformation amount of the mask can be reduced, the time until the mask deformation amount due to the air pressure is reduced to an exposureable amount is shortened, and the narrow gap forming time can be shortened. In other words, since the deformation of the mask is caused by an increase in air pressure, if the maximum air pressure is small, the amount of deformation of the mask is small, and the time for the air to escape from between the mask and the substrate is shortened. Since the masks are parallel, the time when the exposure can be started can be shortened. In other words, this makes it possible to speed up the narrow gap movement and improve the throughput. In addition, by injecting a gas having a viscosity lower than that of air into the air between the mask and the substrate, the maximum pressure when forming a narrow gap is reduced by reducing the viscosity of the air, thereby reducing the deformation of the mask. Thus, the speed of narrow gap movement can be increased.

  (4) The negative pressure means can increase the flow velocity of air exhausted between the mask and the substrate when forming a narrow gap, and as a result, the flow rate can be increased and the maximum pressure when forming a narrow gap can be reduced. It becomes. As a result, the amount of deformation of the mask can be reduced, and the speed of narrow gap movement can be increased.

1 is a schematic apparatus configuration of an exposure apparatus according to a first embodiment. The conceptual diagram of a mask holder. The narrow gap formation operation | movement conceptual diagram. The mask deformation | transformation anticipation figure at the time of narrow gap formation. Mask deformation due to acceleration during narrow gap formation. Temporal displacement of pressure rise during narrow gap formation. Mask deformation due to pressure increase when forming narrow gaps. Relationship between mask movement profile and maximum pressure. FIG. 6 is a diagram illustrating a second embodiment. FIG. 6 is a diagram illustrating Example 3; FIG. 6 is a diagram illustrating Example 4; FIG. 6 is a diagram illustrating Example 5; FIG. 6 is a diagram illustrating Example 6; FIG. 10 is a diagram illustrating Example 7. FIG. 10 is a diagram illustrating Example 8.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  A first embodiment will be described with reference to FIGS. FIG. 1 is a view showing the schematic arrangement of an exposure apparatus according to the first embodiment. This embodiment shows an example of a proximity type exposure apparatus that provides a minute gap (proximity gap) between a mask and a substrate and transfers the mask pattern to the substrate.

  The exposure apparatus includes a base 3, an X guide 4, an X stage 5, a Y guide 6, a Y stage 7, a θ stage 8, a Z mechanism 9 that is driven in a direction perpendicular to the surface of the substrate 1, a chuck 10, and a mask holder 20. It is comprised including.

  In addition to these, the exposure apparatus includes an exposure light source, a supply unit that supplies the substrate 1 to the chuck 10, a recovery unit that recovers the substrate 1 from the chuck 10, a temperature control unit that manages the temperature in the apparatus, and the like. However, in this embodiment, portions not directly related to the invention are omitted.

  In FIG. 1, the chuck 10 is in a delivery position for delivering the substrate 1.

  At the delivery position, the substrate 1 is supplied to the chuck 10 by a supply unit (not shown), and the substrate 1 is recovered from the chuck 10 by a recovery unit (not shown).

  The substrate 1 is mounted on the chuck 10 via a plurality of push-up pins provided on the chuck 10.

  The push-up pin rises from the surface of the chuck 10, receives the substrate 1 from the handling arm of the supply unit, and then descends again to place the substrate 1 on the substrate holding surface of the chuck 10.

  A mask 2 is held by a mask holder 20 above the exposure position where the substrate 1 is exposed. The mask holder 20 is supported by the Z mechanism 9.

  The chuck 10 is mounted on the θ stage 8, and a Y stage 7 and an X stage 5 are provided below the θ stage 8.

  The X stage 5 moves in the X direction (the horizontal direction in the drawing) along the X guide 4 provided on the base 3.

  As the X stage 5 moves in the X direction, the chuck 10 moves between the delivery position and the exposure position. In addition, although a linear motor etc. are used as a drive means, illustration is abbreviate | omitted.

  The Y stage 7 moves in the Y direction (the drawing depth direction) along the Y guide 6 provided on the X stage 5.

  The θ stage 8 rotates the chuck 10 in the θ direction (around the longitudinal axis in the drawing).

  Further, the Z mechanism 9 moves the mask holder in and out of the Z direction (vertical direction in the drawing), that is, in the substrate direction and tilts (tilts) it.

  At the exposure position, the substrate 1 is positioned during exposure by moving the X stage 5 in the X direction, moving the Y stage 7 in the Y direction, and rotating the θ stage 8 in the θ direction.

  In addition, the gap control between the mask 2 and the substrate 1 is performed by the contact and separation of the Z mechanism 9 in the Z direction and the tilt.

  All mechanisms such as the θ stage 8 provided under the chuck 10 may be attached to the mask holder 20. Conversely, the Z mechanism 9 may be provided under the chuck 10.

  FIG. 2 shows a conceptual diagram of a cross section of the mask holder 20.

  The rectangular mask 2 is held at its outer edge by a frame (window) type mask holder 20. This holding force is provided in the mask holder 20 at a portion in contact with the mask 2 through a negative pressure port 22, and a negative pressure pump provided outside via a pipe (not shown) connected to the negative pressure port. (Not shown) is obtained by sucking air.

  A glass 21 is provided on the side opposite to the mask 2.

  This is provided in order to correct the deflection due to the weight of the mask 2. Specifically, the negative pressure piping 23 provided in the mask holder 20 reduces the pressure on the back surface of the mask 2 (negative pressure) to form the negative pressure space 24, thereby correcting the deflection due to the weight of the mask 2. Thus, a parallel surface can be obtained.

  Accordingly, even a large mask can be held close to a gap of several hundreds μm with respect to the substrate 1 supported by the protrusions 11 on the chuck 10.

  In this embodiment, the acceleration of the Z mechanism 9 (in other words, the mask holder) is controlled. Specifically, the acceleration at the time of acceleration of the Z mechanism (in other words, the mask holder) is made larger than the acceleration at the time of deceleration.

  Hereinafter, the acceleration control of the Z mechanism (in other words, the mask holder) will be described in detail.

  FIG. 3 shows a conceptual diagram of the narrow gap forming operation of the mask 2.

  The mask 2 is retracted to a position higher by about 0.5 to 1 mm in order to avoid contact with the substrate 1 when the substrate 1 mounted on the chuck 10 moves below the mask 2. In FIG. 3, the distance H90 between the mask 2 and the substrate 1 is the retracted distance. The narrow gap forming operation is an operation in which the mask 2 moves in the direction of the arrow 30 from the interval H90 and moves to a narrow gap (narrow gap) G92 of several hundred μm from the substrate and stops.

  After forming the narrow gap G, the pattern of the mask 2 is transferred (exposed) onto the substrate 1 by light from a light source (not shown). This method is called proximity exposure. In this proximity exposure, as the narrow gap G is made smaller, the exposure accuracy basically increases. From this viewpoint, it is desirable to make them as close as possible. On the other hand, since the mask 2 is expensive, it is desirable to avoid contact between the mask and the substrate 1. In order to increase the throughput of the apparatus, it is necessary to bring the mask 2 close to the substrate 1 quickly, that is, to increase the speed of forming the narrow gap G92. For the above-described reason, it is important to determine the moving speed profile of the narrow gap forming mask 2.

  FIG. 4 shows a predicted mask deformation during formation of a narrow gap.

  The mask before the formation of the narrow gap G in FIG. 4 (1) is a flat surface without deformation, but during the formation of the narrow gap in FIG. 4 (2), 1) acceleration and 2) the mask 2 with the movement of the mask 2 Deformation due to air pressure generated by compressing the air between the substrates 1 is expected (mask deformation by 31 in FIG. 4B). FIG. 4 (3) shows the mask shape after forming the narrow gap.

  In the exposure apparatus, exposure is performed by determining that the mask is set at a predetermined narrow gap G position, and the deformation amount of the mask at that time is within an allowable range. For this reason, it is important to quickly set the mask 2 at a predetermined narrow gap G position and to quickly suppress the deformation amount of the mask 2 to a predetermined deformation amount or less.

  Here, since the outer edge (periphery) of the mask 2 is held by the mask holder 20, the outer edge of the mask 2 can be positioned in the narrow gap G quickly together with the mask holder 20 (since no deformation occurs). it can. Specifically, the mask holder is connected to a Z mechanism 9 configured by a motor (not shown) that moves the mask holder 20 in a direction in which the mask holder 20 is moved toward and away from the substrate (a direction perpendicular to the mask surface). The mask holder 20 is brought into contact with and separated from the substrate 1 by the motor, and the mask 2 is brought into contact with and separated from the substrate 1. Here, since the mask holder 20 is made of metal and has high rigidity, the amount of deformation is small, and the mask holder 20 and the outer edge (periphery) of the mask 2 held by the mask holder 20 are held by an amount corresponding to the upper and lower sides of the motor. The substrate 1 can be separated.

  On the other hand, since the mask 2 is made of quartz glass and has a small thickness, the mask 2 is deformed into a convex shape by the acceleration at the time of gap formation or air pressure described above, and this deformation amount is less than a predetermined deformation amount (which can be exposed). The shortening of the time to be accommodated leads to a substantially shortened formation time of the narrow gap G. In other words, the mask holder 20 can be positioned at the position of the narrow gap G according to the amount of movement of the motor by the above-described motor, but the mask 2 is deformed by the acceleration and air pressure, and these are predetermined. In this embodiment, it has been found that it takes time to reach the value or less, and this determines the formation time of the narrow gap G.

  Next, mask deformation factors will be described.

  FIG. 5 shows the calculation (deformation analysis) of the deformation amount of the mask 2 by the acceleration at the time of forming the narrow gap. It is assumed that the acceleration is uniformly applied to the entire parallel mask. This is because the masks are parallel due to the function of correcting the deformation due to the weight of the mask using the negative pressure of the mask holder shown in FIG.

  FIG. 5A shows the deformation amount of the entire mask. The curves 501 and 502 represent the deformation of the mask. FIG. 5B shows the deformation amount of the AA ′ cross section of FIG.

  From FIG. 5A, the deformation amount at the center of the mask 2 is the largest. Let this maximum deformation amount be D. Here, in FIG. 5 (2), there is a region where the deformation amount is substantially zero, because the outer edge (periphery) of the mask 2 is gripped by the mask holder 20 and the rigidity of the mask holder is high.

  Next, the deformation amount of the mask due to the pressure when forming the narrow gap will be described. In this embodiment, it is assumed that there is no deformation of the mask, and the air pressure is an external force. FIG. 6 shows the time displacement of the pressure rise when the narrow gap is formed. FIG. 6A shows the mask velocity profile, and FIG. 6B shows the pressure at the center of the mask. Both figures are dimensionless.

  In the speed profile 40 of FIG. 6A, the acceleration time and the deceleration time are both 0.05T, and the acceleration at that time indicates a speed profile (maximum speed V). The speed profile 41 has an acceleration time and a deceleration time of 0.5T, and the acceleration at that time shows a speed profile of 0.1a (maximum speed 0.1V). Here, the speed profile 40 is 10 times faster at the maximum speed than the speed profile 41, and the time of the speed profile is as short as 1/10. Thus, although the speed profile 40 and the speed profile 41 are greatly different, the movement distance of the mask is the same. That is, there are many speed profile combinations even if the movement distance of the mask is the same.

  Next, the speed profile will be described. First, what kind of pressure is generated by the speed profile will be described. Since the movement of the mask here is from H in FIG. 4A to G in FIG. 4C (when a narrow gap is formed), the movement distance of the mask is (HG).

  FIG. 6B shows the pressure fluctuations for the speed profile 40 and the speed profile 41 as pressure fluctuations 50 and 51. The pressure fluctuation indicates the pressure at the center of the mask having the highest pressure. In this embodiment, the pressure increase when forming the narrow gap is symmetrical with the four masks, so the mask is a ¼ model. Further, the mask size is relatively large, while the narrow gap G is as narrow as several hundred μm, so a horizontally long mesh is used. Further, since the mesh size around the mask is reduced and the mask moves, the movement boundary condition will be described. In addition, the description will be given by assuming that air is at room temperature and considering compressibility (isothermal with an ideal gas). On the other hand, the mask is assumed to be a rigid body as described above. In addition, what is necessary is just to use a commercially available fluid analysis code when calculating a pressure.

  It can be seen from the pressure fluctuation 50 in FIG. 6 (2) that the pressure increases as the mask speed increases, the maximum value reaches P, and then decreases as the mask decelerates. It can also be seen that the maximum pressure is about 0.075 T later than 0.05 T at which the mask reaches its maximum speed. Further, the mask speed becomes zero after 0.1T, but it can be seen that the pressure becomes zero after a while. The same applies to the pressure fluctuation 51. The pressure increases as the mask speed increases, and the pressure decreases as the mask speed decreases. Here, in the present embodiment, it has been found that the maximum pressure is not about 0.5 T after the mask reaches the maximum speed, but about 0.8 T. That is, in the present embodiment, it was found that the pressure does not become maximum at the time when the speed becomes maximum, but the maximum pressure increase during deceleration is obtained in the speed profile in which acceleration and deceleration are the same.

  When the maximum values of the pressure fluctuation 50 and the pressure fluctuation 51 are compared, the value is about 1/10 (= 0.1 P / P). This corresponds to the maximum speed being 1/10 (0.1 V / V). This indicates that slowing down the moving speed of the mask is effective in suppressing the pressure increase.

  However, if the movement speed of the mask is slowed, the maximum value of the pressure rise is suppressed, but the time for the narrow gap movement itself is increased. That is, reducing the mask moving speed is a request that contradicts the purpose of shortening the time for narrow gap movement (the entire speed profile).

  Therefore, in this embodiment, if the speed profile is set such that the maximum value of the pressure rise can be suppressed without extending the entire speed profile, the amount of deformation of the mask due to the pressure rise can be reduced. It has been found that the gap moving time can be shortened, and as a result, the throughput can be improved.

  Next, the effect of these pressure increases on mask deformation will be described. Specifically, the deformation amount of the mask will be described on the assumption that a pressure (P / 2) that is half of the maximum pressure P generated at the time of the velocity profile 40 is equally applied to the mask 2. Here, P varies depending on the mask moving speed V, the moving distance (HG), the time T, and the like, but the possible maximum value P will be described.

  FIG. 7 shows the deformation amount of the mask when P / 2 air pressure is applied. It can be seen from FIG. 7A that the maximum displacement of the mask is at the center of the mask. Further, as shown in FIG. 7B, the magnitude Dp is larger than the deformation amount Da due to acceleration (Dp> Da), indicating that the deformation due to pressure is dominant. The measurement distance in FIG. 7 (2) is a measurement distance when measured from A to A ′ in FIG. 7 (1). Since the outer edge (periphery) of the mask is held by the mask holder, there is a region where the deformation amount is substantially zero. As can be seen from FIG. 7A, the amount of deformation is convex in the direction opposite to the substrate 1, so that the mask 2 and the substrate do not contact each other.

  In addition, this means that even if the mask holder 20 is close to a position of several hundred μm from the substrate to form a narrow gap, the central portion of the mask 2 is deformed to protrude in the opposite direction to the substrate due to air pressure. It shows that

  The mask deformation amount Dp due to the air pressure P at the time of forming the narrow gap is a value that cannot be ignored with respect to the narrow gap G, and that the reduction of the deformation amount contributes to the speeding up of the narrow gap formation in this embodiment. I found it.

  Further, since this deformation is caused by air pressure, when air is discharged instantaneously, this deformation disappears, and it does not take time to return to flatness. However, due to the air pressure, the center of the mask is greatly swollen to confine air, while the periphery (the outer edge) is close to the substrate by the mask holder, so the outlet of the air is narrowed. The central air is not discharged outside, and the mask deformation is maintained for a long time. Specifically, due to the narrow gap formation, the center of the mask bulges convexly with air pressure. On the other hand, the periphery of the mask from which air is exhausted closes the substrate up to several hundred μm and closes the air outlet, so that it is difficult for air to escape out of the mask, and it takes time for this air to be exhausted. Therefore, it takes time for the mask to become a predetermined deformation amount or less, and as a result, it takes time to form the narrow gap.

  For this reason, it has been found in the present embodiment that reducing the pressure generated during the formation of the narrow gap reduces the amount of mask deformation and, as a result, contributes to speeding up the formation of the narrow gap.

  From the above, if the mask moving speed is slowed down, the pressure rise will be small and the mask deformation will be small, but it takes time to move the mask to the narrow gap position (because the speed profile end time becomes long). Contrary to speeding up narrow gap movement.

  On the other hand, when the speed is increased, the periphery of the mask (outer edge) quickly reaches the narrow gap position (although the speed profile end time is shortened), but the mask is greatly deformed by the increase of air pressure, and the amount of deformation is predetermined. It takes time until the value becomes equal to or less than this value, and as a result, the formation of the narrow gap cannot be accelerated.

  For this reason, in this embodiment, it is found that if a speed profile that can reduce the maximum air pressure without increasing the speed profile end time is set, a narrow gap can be formed at high speed. .

  FIG. 8A is a diagram for explaining a case where the acceleration during acceleration and the acceleration during deceleration are changed in the relationship between the time T and the mask moving speed V. FIG. FIG. 8 (2) is a diagram for explaining the maximum pressure fluctuation when the acceleration is changed.

  Specifically, in FIG. 8A, the acceleration and deceleration times are the same (that is, the acceleration during acceleration and the acceleration during deceleration are the same 0.5T), the symmetrical velocity profile 70, and the mask velocity are 0.5T. The second half maximum speed profile 71 (acceleration time 0.75T, deceleration time 0.25T) that reaches the maximum speed later than the second half, and the first half maximum speed profile 72 (acceleration time) that reaches the maximum speed earlier than 0.5T. 0.25T, deceleration time 0.75T). FIG. 8 (2) shows the maximum pressure fluctuations. Here, the symmetrical velocity profile 70 is referred to as a reference profile. In this case as well, the narrow gap formation will be described with respect to a velocity profile that moves in the T time from the H position to the G (exposure gap) position.

  The pressure fluctuation with respect to the reference profile 70 in FIG. 8A is the pressure fluctuation 80 in FIG. From the comparison of both figures, the time for the mask to reach the maximum speed is 0.5T after the start of movement, but the maximum pressure is about 0.75T later than that. Now, let P be the maximum pressure value.

  Next, when the symmetrical profile of the reference speed profile is changed to the latter half maximum speed profile 71 of FIG. 8 (1), the maximum pressure is 1 like the pressure fluctuation 81 of the latter half maximum speed profile of FIG. 8 (2). It increases to .4P (about 1.4 times), and its arrival time also shifts backward to about 0.8T.

  On the other hand, when the first half maximum speed profile 72 of FIG. 8 (1) is used, the maximum pressure is the pressure fluctuation 82 of the first half maximum speed profile of FIG. 8 (2), and the maximum pressure is about 0 from the pressure P of the reference profile. It decreases to 0.8P, and its arrival time is before 0.75T.

  That is, when the profile of the mask formation speed at the time of narrow gap formation is changed from the symmetric speed profile 70 to a speed profile in which the acceleration at the time of acceleration is greater than the acceleration at the time of deceleration, that is, the first half maximum speed profile 72. It was found in this example that the maximum pressure can be reduced.

  On the other hand, it was also found in this embodiment that the maximum pressure increases when the speed profile is the latter half maximum speed profile 71.

  Since these velocity profiles have the same time from the start to the end, this does not slow down the mask movement. In addition, since only the maximum pressure can be reduced, the amount of deformation of the mask can be kept small. Therefore, the time until the deformation of the mask caused by the pressure increase during the movement of the mask is eliminated (becomes a predetermined value or less). As a result, the narrow gap formation time can be shortened.

  Further, the acceleration time of the speed profile of FIG. 8 (1) is shortened from 0.125T (maximum speed V, not shown) to 0.05T (maximum speed V, not shown) to reach the maximum speed. The pressure fluctuations in the speed profile in which the time until the time is shortened are shown in the pressure fluctuation 83 and the pressure fluctuation 84 in FIG.

  From the figure, the maximum pressure becomes smaller when the pressure fluctuation is 82 as compared with the reference profile pressure fluctuation 80, and when the time to reach the maximum speed is shortened, the pressure fluctuation 83 and the pressure fluctuation 84 are shown. In addition, the maximum pressure is further reduced. However, it can be seen that the effect (amount) of reducing the maximum pressure is reduced.

  Therefore, even if the acceleration is increased unnecessarily, specifically, even when the acceleration is made infinite and the mask speed is instantaneously set to the maximum speed V, the acceleration is compared with the maximum pressure of 0.05T. The maximum pressure cannot be significantly reduced. Of course, ideally (theoretically) an L-shaped (right triangle) velocity profile with infinite acceleration is desirable. However, in reality, it is practically (practical) to aim for a speed profile close to the L shape with the maximum acceleration of the motor of the tilt mechanism 9.

  From the above, it is effective to reduce the maximum pressure rise by changing the speed profile from the symmetrical speed profile in which the acceleration and deceleration times are the same to the first half acceleration profile in which the first half has the highest speed.

  The more the time for maximum speed is shifted forward from the center of the speed profile, the smaller the maximum pressure. However, the reduction effect is small.

  The above-mentioned phenomenon, that is, the speed profile is an untargeted speed that reaches the maximum speed (at an earlier time) before the center (intermediate) time of the speed profile from the speed profile (reference) that is symmetric during acceleration and deceleration If the mask is moved in the profile, the maximum pressure can be reduced because the size of the mask, the narrow gap formation start position H, the stop position G (exposure position), and the required time T (mask movement speed) Even if it changes, the basic trend will not change.

  Further, this phenomenon becomes more prominent as the mask is larger, the mask moving speed is faster, and the stop position G (exposure position) is smaller. It is valid.

  In this embodiment, the time required to reach the maximum speed of the mask movement speed profile when forming a narrow gap is earlier than the center time of the entire speed profile (from start to stop) (early time, close to start). In order to control the maximum speed.

  As a result, the maximum pressure of pressure fluctuation can be reduced while keeping the entire speed profile time the same, and as a result, the amount of mask deformation due to air pressure can be reduced. For this reason, the time until the mask is deformed by air pressure and returns to the flatness can be shortened. As a result, the narrow gap forming time can be shortened. For this reason, it is possible to improve the throughput and improve the performance of the exposure apparatus.

  In the present embodiment, since the speed profile of the motor of the tilt mechanism that moves the mask holder in and out of the mask direction may be changed as described above, the present invention can also be applied to an existing exposure apparatus.

  Of course, a new control system (mechanism) may be added to perform the above-described control.

  FIG. 9 shows a second embodiment of the present invention.

  The difference between the second embodiment and the first embodiment is that the Z mechanism 9 provided in the mask holder 20 is provided on the opposite side of the mask holder with respect to the substrate 1, in other words, on the lower side (back side) of the substrate. It is. Specifically, the Z mechanism 9 of the present embodiment is disposed, for example, between the chuck 10 and the θ stage 8.

  By providing the Z mechanism 9 below the chuck 10 from the mask holder 20, a mechanism for moving the mask holder 20 up and down becomes unnecessary, the mechanism around the mask holder 20 is simplified, and the top frame ( It is possible to improve the accuracy of attachment to a mask (not shown), and as a result, it becomes easy to achieve parallelism (flatness) of the mask.

  Furthermore, the suction force (negative pressure) for holding the mask 2 in a vacuum can be reduced in order to keep the mask stationary and the substrate 1 in contact with and away from the mask, and the negative pressure pump can be made small. Can reduce the cost of the apparatus.

  In the first embodiment, in order to move the mask 2 up and down at high speed, the suction force of the negative pressure port 22 of the mask holder 20 must be increased so as to withstand the acceleration (so as not to separate the mask 2). There are cases where it is necessary. In particular, since the weight of the mask 2 is supported only by the suction force of the mask holder 20, it is essential to improve the negative pressure. Furthermore, as the mask 2 is moved up and down at high speed, the amount of deformation of the mask 2 increases due to the acceleration.

  On the other hand, in Example 2, the chuck 10 is moved up and down, and as a result, the substrate 1 mounted thereon is moved up and down. Here, since the rigidity of the chuck 10 is high, the amount of deformation due to the vertical acceleration of the chuck 10 is small, and as a result, the deformation of the substrate mounted thereon is small. For this reason, it is possible to increase the acceleration of forming the narrow gap, and as a result, it is possible to increase the speed of forming the narrow gap.

  Again, in Example 2, since the mask 2 is stationary, there is no need to consider deformation due to acceleration, and the acceleration can be increased to increase the speed of narrow gap formation.

  Here, the speed at which the chuck 10 is brought into and out of contact with the mask 2, that is, the speed of the chuck 10 by the Z mechanism 9, is the acceleration at the time of acceleration in the mask speed profile when the narrow gap is formed, as in the first embodiment. However, the speed profile is such that it is larger than the acceleration at the time of deceleration, in other words, the time to reach the maximum speed is ahead of the time center of the speed profile (to reach in a short time). For this reason, it is possible to reduce the maximum value of the pressure increase at the time of forming the narrow gap, thereby reducing the amount of mask deformation due to the pressure. As a result, the mask deformation is eliminated and the exposure start time can be shortened.

  For this reason, also in the second embodiment, as in the first embodiment, the narrow gap forming speed can be increased, and the throughput can be improved.

  A third embodiment is shown in FIG.

  In the third embodiment, as in the speed profile of the first embodiment (that is, like the first half maximum speed profile 72 in FIG. 8), the position (time) at which the maximum speed is reached is forward from the center of the speed profile. The point to bring is the same.

  The difference between the third embodiment and the first embodiment is that the acceleration of this embodiment is variable, and the speed profile is a curved speed profile like the speed profile 103 of FIG. Specifically, in the third embodiment, the acceleration speed profile is variable to a convex curve, and the deceleration speed profile is variable to a concave curve.

  By adopting such a speed profile, the maximum pressure increase can be reduced as in the first embodiment.

  Further, by making the acceleration variable, it is possible to reduce the change in speed of the mask moving speed from the acceleration to the deceleration, and to reduce the speed fluctuation until the motor is decelerated and stops. Can suppress vibration.

  As a result, the vibration of the mask can also be suppressed. For this reason, it is considered that the time until exposure can be shortened and the narrow gap forming speed can be further increased.

  Although a curved velocity profile is shown here, a polygonal velocity profile may be used instead of a curved line.

  That is, in the reference speed profile 70 of FIG. 10, the area (movement distance) on the left and right of 0.5T is the same for switching between acceleration and deceleration. On the other hand, the speed profile of this embodiment is characterized in that the area (movement distance) on the side earlier than 0.5T (the side closer to time 0) is large. That is, the larger the area (moving distance) before the central point (time) of the velocity profile, the smaller the pressure rise.

  For this reason, although the speed profile is a straight line or a curved line, it is desirable to increase the area in the first half of 0.5T.

  Again, ideally, if the acceleration of the motor (mask holder) is infinite, the speed profile at which the mask speed reaches V at time 0 and then becomes zero at time T is the pressure profile. It is desirable from the viewpoint of reducing the rise.

  However, since the acceleration of the motor is finite, it is desirable to control the speed profile based on the acceleration characteristics of the motor.

  FIG. 11 shows a fourth embodiment of the present invention.

  The difference between the fourth embodiment and the first embodiment is that, in this embodiment, a low viscosity for jetting a gas having a viscosity lower than that of air onto the substrate 1 around the chuck 10 (for example, both ends). This is the point where the gas ejection nozzle 100 is provided. Specifically, when the mask 2 approaches the substrate 1 (preferably immediately before), a low-viscosity gas is ejected from the nozzle 100 between the substrate and the mask.

  As an effect of this, the increase in air pressure when forming a narrow gap increases due to the viscosity of air, so that the pressure increase can be reduced by ejecting a gas having a lower viscosity than air when forming a narrow gap. .

  Specifically, the viscosity of air is 18.4 μPa · s, for example, that of hydrogen is 8.9 μPa · s. For this reason, if the air between the mask 2 and the substrate 1 can be replaced with hydrogen, the viscosity thereof is about ½, so that the pressure increase can be reduced to about ½ compared with air.

  Since the other configuration is the same as that of the first embodiment, the same effect as that of the first embodiment can be obtained, and the increase in pressure can be further reduced by using a gas having a low viscosity. It can be made small, and the speed of narrow gap formation can be increased.

  FIG. 12 shows a fifth embodiment of the present invention.

  The difference between the fifth embodiment and the first embodiment is that, in addition to the Z mechanism 9 provided in the mask holder 20, the second Z mechanism 9 is placed on the opposite side of the mask holder with respect to the substrate 1, in other words, the substrate. Is provided on the lower side (back side). Specifically, the second Z mechanism 9 of the fifth embodiment is disposed, for example, between the chuck 10 and the θ stage 8.

  The second Z mechanism 9 is driven in a direction perpendicular to the surface of the substrate 1 in accordance with the operation of the Z mechanism 9 provided in the mask holder 20. As a result, both the mask 2 and the stage 1 can move so as to approach and separate.

  Here, in the fifth embodiment, the relative movement between them, that is, the speed profile is the same as that of the first embodiment, and is, for example, the first half maximum speed profile 72 of the first embodiment. For this reason, the increase in pressure between the mask 2 and the substrate 1 is reduced, and the speed of narrow gap formation can be increased as in the first embodiment.

  In this embodiment, since both the mask 2 and the substrate 1 move, the acceleration at the start of narrow gap formation can be made faster, and an ideal right triangle (L time type) speed profile is obtained. It can be closer. For this reason, the pressure rise between both can be made small and narrow gap formation earlier than a 1st Example can be anticipated.

  In the proximity exposure apparatus that performs exposure with the mask close to the substrate, the maximum air pressure between the mask and the substrate at the time of forming the narrow gap can be reduced by using Example 5, so that the mask deformation becomes small, The gap formation time can be shortened. As a result, the throughput of the apparatus can be improved.

  FIG. 13 shows a sixth embodiment of the present invention.

  The difference between the sixth embodiment and the first embodiment is that in the sixth embodiment, negative pressure means 200 for sucking the atmosphere is provided on the outer edges of the substrate 1 (in other words, the chuck 10) and the mask 2. . Specifically, as shown in FIG. 13 (1), a nozzle 202 having an inlet 201 on the outer edge of the substrate 1 placed on the chuck 10, a fixing portion 203 for fixing the nozzle 202 to the chuck 10, and suction from the nozzle 202. There is provided negative pressure means 200 constituted by a pipe 204 for taking out the air out of the chuck 10.

  The air inlet 201 is inclined, and at least a part of the air inlet 201 exists between the mask 2 and the substrate 1. By inclining, it becomes possible to bring the mask 2 close to the substrate 1 regardless of the insertion of the nozzle, and by inserting a part of the intake port between them, the air is effectively discharged. it can.

  The other end of the pipe 204 is provided with a negative pressure pump 605 provided with a control means for controlling negative pressure (aspiration amount) and suction time.

  At least one or more negative pressure means 200 are provided on the entire circumference of the substrate 1 along the outer edge of the substrate 1, for example. As shown in FIG. 13 (2), the negative pressure means 200 has an air flow 205 generated between the two when the mask 2 approaches the substrate 1 to form a narrow gap (from the center of the mask 2 to the outer edge of the mask 2). A function of sucking the airflow flowing toward the outside through the suction hole 201 and letting it out between the mask 2 and the substrate 1.

  That is, the high pressure air generated between the substrate 1 and the mask 2 when the narrow gap is formed flows out from between the two in a short time by the negative pressure means 200, so that the deformation amount of the mask 2 by the high pressure air is reduced. It becomes possible to do. Thereby, the deformation of the mask 2 can be reduced by the high-pressure air at the time of forming the narrow gap, so that the narrow gap forming time can be shortened.

  Here, the suction is started and stopped by the negative pressure means 200 after the mask 2 starts to form a narrow gap (when the mask 2 starts to decrease from the height H), the suction is started and the mask 2 reaches the height G. When it reaches, stop the suction.

  Here, the suction amount is a suction amount corresponding to the amount of air discharged when the mask moves from the height H to G. That is, the suction amount Q is Q = mask area x (height H−height G). In other words, if the mask 2 sucks the air amount from the height H to the height G by forming the narrow gap, the pressure of the air rises and the deformation of the mask 2 is not induced, and the narrow gap is formed. It is possible to increase the speed.

  Here, the negative pressure means 200 is a syringe pump, that is, a syringe-like cylinder pump, and the flow rate of the pump is controlled to be the same as the flow rate Q by managing the flow rate Q. Becomes easier. That is, as the narrow gap movement starts, the syringe pump starts to be pulled, and at the same time as the narrow gap movement ends, the predetermined flow rate Q is adjusted so as to finish pulling to match the movement of the mask 2 with the mask 2. And can be easily extracted from the substrate 1.

  When the mask 2 reaches the height G of the narrow gap, the suction is stopped by the negative pressure means 200. If the negative pressure means 200 is kept operating, the air between the mask 2 and the substrate 1 This is because it is discharged and becomes a vacuum (a value lower than the atmospheric pressure), and the mask 2 is pulled downward to bend. That is, if the negative pressure means 200 is operated even after the narrow gap is formed, the mask 2 is deformed and becomes an obstacle to the narrow gap formation. This must be avoided.

  The suction control described above can be expressed as corresponding to the pressure of the high-pressure air generated between the substrate 1 and the mask 2, that is, the movement of the mask holder. As another expression, as the pressure of the high pressure air generated between the substrate 1 and the mask 2 increases, the negative pressure of the negative pressure means 200 increases, and as the pressure of the high pressure air generated between the substrate 1 and the mask 2 decreases. It can be expressed that the negative pressure of the negative pressure means 200 is controlled to be small.

  In this embodiment, the same effect as that of the first embodiment can be expected.

  FIG. 14 shows a seventh embodiment of the present invention.

  The difference between the seventh embodiment and the sixth embodiment is that the negative pressure means 210 is provided in the mask holder 20 adjacent to the mask 2 in the seventh embodiment.

  As shown in FIG. 14 (1), the negative pressure means 210 is provided with an intake port 211 facing the substrate 1, and a surface 212 facing the substrate 1 provided with the intake port 211. , 213 are set to the same height as the surface 215 of the mask 2 facing the substrate 1.

  Example 7 will be described with reference to FIG.

In Example 7, since the substrate 1 facing surface of the negative pressure means 210 is provided at the same height as that of the mask 2, the following effects can be obtained.
(1) Even if the negative pressure means 210 is provided, the mask 2 can be brought close to the substrate 1 as in the case where the negative pressure means 210 is not provided.
(2) Since the negative pressure means 210 is provided in the mask holder 20, it is necessary to replace the negative pressure means 210 even when the substrate 1 is larger than the mask 2 and exposure is performed while moving the position of the substrate 1. It can be done easily.
(3) From the center of the mask 2 in the air flow 217 sucked from the intake port 211 by increasing the outer width W1 of the negative-pressure means 210 on the substrate-facing surface W2 on the mask 2 side. The air flow 216 can be sucked in a larger flow rate than the air flow 218 from the outside, and the air between the mask 2 and the substrate 1 is discharged out of the mask 2 more efficiently. It becomes possible.

  In particular, the wider W1, the larger the air flow 218 entering the air inlet 217 from the outside due to the increased flow path resistance, resulting in a smaller flow rate of the air flow 218. As a result, as described above, the air flow 216 from the mask 2 can be effectively discharged from between the mask 2 and the substrate 1. As a result, the same effect as in the sixth embodiment can be expected.

  FIG. 15 shows an eighth embodiment.

  The difference between the eighth embodiment and the sixth embodiment is that the air pressure between the substrate 1 and the mask 2 is made smaller than the atmospheric pressure. As a result, it is possible to reduce the pressure increase of air, which has been an obstacle when forming the narrow gap, and to improve the speed of forming the narrow gap.

  Specifically, as shown in FIG. 15 (1), the negative pressure means 220 causes the air in the mask 2 and the substrate 1 to flow out of the mask as an air flow 225. For this reason, there is an advantage that the negative pressure means need not be adjusted in accordance with the mask operation, the control becomes simple, and the manufacture becomes easy.

  The negative pressure means 220 has basically the same configuration as the negative pressure means 200 described above, and is connected to a nozzle 222 having an intake port 221 and a fixing portion 223 and a nozzle 222 for fixing the nozzle 222 to the chuck 10 to carry an air flow. It is comprised from this piping 224.

  A negative pressure pump is connected to the other end of the pipe 224 (not shown).

  Due to the negative pressure means 220, the pressure P1 between the substrate 1 and the mask 2 is smaller than the atmospheric pressure (atmospheric pressure P0) of the exposure apparatus (P1 <P0).

  Here, the smaller P1 is, the smaller the air resistance (air pressure rise) when the mask 2 moves in a narrow gap. For this reason, although it is desirable to make it small from a viewpoint of reduction of an air pressure rise, the enlargement (performance improvement) of a negative pressure pump is needed.

  Further, when the pressure between the mask 2 and the substrate 1 is reduced to P1, the mask 2 is also pulled by the negative pressure and becomes convex in the direction of the substrate 1. For this reason, as shown in FIG. 15 (2), the space 24 between the mask 2 and the glass 21 of the deflection correcting means due to the weight of the mask and the mask is also at substantially the same pressure P1 as the surface of the mask 2 facing the substrate 1. It is necessary to reduce the pressure.

  However, if the same P1 is used on the front and back of the mask, the mask 2 is convex toward the substrate 1 by the weight of the mask, so that it is necessary to further reduce the atmospheric pressure by the amount of correction of the deflection due to the weight. .

  Specifically, if the negative pressure (atmospheric pressure) due to the weight of the mask 2 is ΔP, the atmospheric pressure in the space 24 needs to be reduced to P1−ΔP.

  FIG. 15 (3) shows a state in which the mask 2 forms a narrow gap (gap G). At this time, the pressure of the substrate 1 and the mask 2 is P1.

  In other words, regardless of before and after the formation of the narrow gap, the pressure between the mask 2 and the substrate 1 is always kept smaller than the atmospheric pressure P0, so that the air pressure is increased even when the narrow gap of the mask 2 is formed. Since it can be made small, the speed of narrow gap formation can be increased.

  As an extreme example, if an atmospheric pressure close to approximately zero atmospheric pressure can be realized, the air resistance (increase in air pressure) becomes substantially zero, and the mask will not be deformed due to an increase in pressure when forming a narrow gap. As a result, a high-speed narrow gap can be formed.

  As described above, in this embodiment, the reason why the speed of narrow gap formation is increased is mask deformation due to high pressure of air generated when the mask 2 is close to the substrate 1. .

  And even in the mask speed profile of the same time (length), the time Tmax to reach the maximum speed is made shorter than 1/2 of the entire time T of the speed profile (Tmax <T / 2), so that It was explained that the maximum pressure can be reduced.

  Then, it has been explained that it is possible to increase the speed of narrow gap formation by using the mask speed profile.

  Further, as another method for reducing the pressure increase when forming the narrow gap, a low-viscosity gas is mixed into the air between the mask 2 and the substrate 1 to reduce the viscosity of the air, thereby reducing the pressure rise and narrowing. It was explained that the gap formation can be speeded up.

  Further, it has been explained that the negative pressure means can increase the flow velocity of air discharged from between the mask and the substrate when forming the narrow gap, so that the maximum pressure when forming the narrow gap can be lowered. As a result, it has been explained that the amount of deformation of the mask can be reduced and the speed of narrow gap movement can be increased.

1 Substrate 2 Mask 3 Base 4 X guide 5 X stage 6 Y guide 7 Y stage 8 θ stage 9 Z mechanism 10 Chuck 11 Protrusion (bank, vacuum compartment)
20 Mask holder 21 Glass (for negative pressure deflection correction means)
22 Negative pressure port 23 Negative pressure piping 24 Negative pressure space 30 Mask moving direction 31 when narrow gap is formed 31 Mask deformation factor (acceleration + air pressure) during narrow gap formation
40 speed profile (acceleration = deceleration = 0.05T, maximum speed V)
41 Speed profile (acceleration = deceleration = 0.5T, maximum speed 0.1V)
50 Pressure fluctuation (for mask speed profile 40)
51 Pressure fluctuation (for mask speed profile 41)
70 Symmetric velocity profile (acceleration = deceleration = 0.5T, maximum velocity V)
71 Second half maximum speed profile (acceleration = 0.75T, deceleration = 0.25T, maximum speed V)
72 First half maximum speed profile (acceleration = 0.25T, deceleration = 0.75T, maximum speed V)
80 Pressure fluctuation (in case of symmetrical velocity profile mask 70)
81 Pressure fluctuation (in the latter half maximum speed profile 71)
82 Pressure fluctuation (first half maximum speed profile 72)
83 Pressure fluctuation (acceleration = 0.125T, deceleration = 0.875T, maximum speed V)
84 Pressure fluctuation (acceleration = 0.05T, deceleration = 0.95T, maximum speed V)
90 interval H
91 Distance between mask and substrate 92 Narrow gap G (space between substrate and chuck during exposure)
100 Nozzle 200, 210, 220 Negative pressure means 201, 211, 221 Intake port 202, 222 Nozzle 203, 223 Fixed portion 204, 224 Pipe 205, 217, 225 Air flow 212, 213, 215 Opposing surface 216 Air from mask center Flow 218 Air flow from outside

Claims (6)

In an exposure apparatus that exposes a substrate,
A chuck for mounting the substrate;
A positioning part for positioning the chuck;
Holding a mask for exposing a pattern to the substrate, and a mask holder close to the substrate;
A control unit for controlling the acceleration of the mask holder;
An exposure unit that irradiates light to the mask, and the control unit accelerates the mask holder at the first acceleration when forming a narrow gap between the mask holder and the substrate, Decelerate at the second acceleration,
The exposure apparatus characterized in that the first acceleration is larger than the second acceleration . The exposure apparatus according to claim 1,
The exposure apparatus according to claim 1, wherein the mask holder is accelerated by the first acceleration and then decelerated by the second acceleration . The exposure apparatus according to claim 1 ,
The exposure apparatus , wherein the control unit changes at least one of the first acceleration and the second acceleration . The exposure apparatus according to claim 1,
A supply unit for supplying a medium having a viscosity lower than that of air;
The exposure apparatus, wherein the supply unit supplies the medium to the substrate . The exposure apparatus according to claim 1,
The exposure apparatus according to claim 1, wherein the chuck moves upward and / or downward relative to the surface of the substrate in accordance with the operation of the mask holder . The exposure apparatus according to claim 1,
An exposure apparatus comprising: a suction unit that sucks an atmosphere between the chuck and the mask holder .

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