JP2013106007A - Stage device, exposure equipment and device manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stage device which is advantageous for reduction of a residual stress in accordance with height adjustment of a substrate holding part.SOLUTION: A stage device includes: a substrate; a substrate holding part which holds the substrate; and at least one support part which is installed on the substrate to support the substrate holding part so that a position of the substrate holding part can be changed. Each of the at least one support part includes: one first adjustment part; a plurality of second adjustment parts; and a control part. The first adjustment part has: one end fixed on the substrate; and the other end fixed to the substrate holding part, and can adjust a position of the other end. The second adjustment parts have: one ends fixed on the substrate; and the other ends which can be switched to a first state of being connected to the substrate holding part and a second state without being connected to the substrate holding part, and can independently adjust the positions of the other ends. The control part performs control so that all the connection states of the other ends of the plurality of second adjustment parts become the second state while the position of at least one of the other ends of the plurality of second adjustment parts and the first adjustment part is adjusted.

Description

  The present invention relates to a stage apparatus, an exposure apparatus, and a device manufacturing method.

Liquid crystal display elements and semiconductor elements are manufactured by a photolithography technique in which a pattern formed on a mask is transferred onto a substrate such as a glass plate or a wafer. An exposure apparatus used in this photolithography process includes a substrate stage on which a substrate is moved and a mask stage on which a mask having a pattern is mounted and moved. This exposure apparatus projects and transfers a pattern formed on a mask onto a substrate via a projection optical system while sequentially moving the mask stage and the substrate stage. In order to maintain the transfer accuracy, it is necessary to reduce the flatness of the upper surface of the substrate. For this purpose, high-precision processing of individual component parts and height adjustment during assembly are performed.
Regarding the processing of individual component parts, the target flatness is realized by processing in the state where the same stress conditions as in actual use are reproduced. Regarding the height adjustment, an adjustment mechanism capable of fine adjustment is provided in the exposure apparatus to adjust the height on the micron order to achieve a predetermined flatness. The adjustment mechanism is configured between a substrate holding unit that holds the substrate and a support unit that supports the substrate holding unit. The entire upper surface of the substrate holding portion has an ideal flatness by driving the adjusting mechanism in the Z direction.
A conventional technique for adjusting the flatness of the upper surface of the substrate holder will be described. Patent Document 1 discloses a substrate stage apparatus having a mechanism capable of adjusting the height. In this substrate stage apparatus, a plurality of height adjusting mechanisms are arranged in the horizontal direction under the substrate holding unit, and the flatness of the upper surface of the substrate holding unit is adjusted in conjunction with the measurement system and the electric control unit. However, Patent Document 1 does not mention fixing the substrate holding unit and the height adjusting mechanism. Therefore, in the substrate stage apparatus described in Patent Document 1, there is a concern that when the height of the substrate holding part is adjusted, residual stress is generated in a part of the substrate stage apparatus, and the flatness of the substrate holding part changes over time. is there. Patent Document 2 proposes a method of releasing stress in the horizontal direction by using a leaf spring between the substrate holding portion and the height adjusting mechanism. There remains concern about change.

JP 2009-218372 A JP 2004-165582 A

  As described above, the conventional stage apparatus that can adjust the flatness of the upper surface of the substrate holding unit has a structure in which residual stress is generated between the substrate holding unit and the height adjustment mechanism. The flatness of the film will change over time. As a result, a loss due to a substrate defect is caused.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a stage apparatus that is advantageous in reducing the residual stress accompanying the height adjustment of the substrate holder.

  In order to achieve the above object, the present invention provides a stage device that holds a substrate and is movable in a direction orthogonal to the surface of the substrate, the substrate, a substrate holding unit that holds the substrate, and the substrate And at least one support portion that supports the substrate holding portion so that the position of the substrate holding portion in the direction can be changed, and each of the at least one support portion is fixed on the base. A first adjusting portion that can adjust the position of the other end portion in the direction, and one end portion fixed on the base. And a second state that can be switched between a first state that is coupled to the substrate holding unit and a second state that is not coupled to the substrate holding unit, and the position of the other end in the direction Multiple second adjusters that can be adjusted individually While the positions of at least one other end of the plurality of second adjustment units and the first adjustment unit in the direction are adjusted, all the coupling states of the other end portions of the plurality of second adjustment units are the first A control unit that controls the first adjustment unit and the plurality of second adjustment units so as to be in two states.

  An object of the present invention is to provide a stage apparatus that is advantageous in reducing residual stress associated with height adjustment of a substrate holding portion.

Diagram showing exposure equipment Diagram showing substrate stage Diagram showing substrate stage drive sequence Diagram showing an example of multiple vacuum chuck mechanisms Diagram showing vacuum chuck mechanism Diagram showing electrostatic chuck mechanism Diagram showing the height adjustment mechanism

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

  First, an exposure apparatus to which the stage apparatus of the present invention can be applied will be described. FIG. 1 is a conceptual diagram showing the overall configuration of the exposure apparatus. A mask stage 20 is disposed above the projection optical system 10 in the vertical direction, and a substrate stage (stage apparatus) 30 is disposed below. The mask stage 20 and the substrate stage 30 can be individually moved, and the movement positions of both the mask stage 20 and the substrate stage 30 can be measured and controlled by the laser interference length measuring device 50.

  The substrate stage 30 has a Y stage 32 and an X stage 33 arranged on the main body base 31 in the orthogonal direction. A θZ stage 34 is mounted on the X stage 33 via support legs 150 that can be individually varied in the vertical direction, and a θ rotation mechanism 120 in the XY plane is disposed thereon, and further a substrate holding unit is disposed thereon. One or more substrates 37 and substrate holders 35 are mounted in accordance with the substrate size. The substrate holding unit 35 holds the substrate 36 to be exposed.

  A method for holding the substrate 36 will be described. Although not shown in FIG. 1, an air pipe is configured in the substrate holding portion 35. The substrate holding unit 35 can suck and hold the substrate 36 by a vacuum chuck mechanism (not shown) provided on the upper surface of the substrate holding unit 35 on the back surface of the substrate 36 and can be detached and released. When the substrate holding unit 35 vacuum chucks the substrate 36, the substrate 36 can be moved in the X, Y, and Z directions by the substrate stage 30, and is also rotatably supported in the XY plane. The θZ stage 34 causes the surface of the substrate 36 to coincide with the substrate-side focal plane of the projection optical system 10 during exposure. The flatness of the upper surface of the substrate 36 or the substrate holding unit 35 is at least one support that is installed on the base and supports the position of the substrate holding unit 35 in a direction orthogonal to the surface of the substrate 36 (vertical direction). It is adjusted by the unit 60.

  The mask stage 20 includes a mask stage surface plate 21 and an XYθ stage 22 disposed thereon, and a mask 23 having a pattern to be projected thereon is disposed. Therefore, the mask 23 can be moved in the X and Y directions and is supported rotatably in the XY plane. Above the mask stage 20, an observation optical system 40 capable of observing images of the mask 23 and the substrate 36 via the projection optical system 10 is disposed, and an illumination optical system 41 is disposed further above.

  Both the mask stage 20 and the substrate stage 30 are position-measured by a laser interference length measuring device 50. The laser interference length measuring device 50 includes a laser head 51, interference mirrors 52 and 53, a first reflection mirror 54 attached to the θZ stage 34, and a second attachment attached to the mask stage surface plate 21. A reflection mirror 55. Here, the laser beam position of the laser interference length measuring device 50 is projected substantially on the mask-side focal plane of the projection optical system 10 in the vertical direction (in the optical axis direction of the projection optical system 10) with respect to the mask stage 20, and in the horizontal plane. The optical axis position of the optical system 10 is set. The laser beam position of the laser interferometer 50 is also set to the optical axis position of the projection optical system 10 in the horizontal plane for the substrate stage 30 and passes through the substrate-side focal plane of the projection optical system 10 in the vertical direction. Is set.

  FIG. 2 is a schematic view of a substrate stage 30 to which the present invention is applied. This embodiment shows a state where one support portion 60 is configured for one substrate holding portion 35. The support unit 60 includes a plurality of second adjustment units 63a, a first adjustment unit 63b, a first adjustment unit 63b, and a control unit that controls the second adjustment unit 63a. The control unit includes an arithmetic control unit 99 and an air control unit 64 which will be described later. One end of the first adjustment unit 63b is fixed on the base 37, the other end 62 is fixed to the lower surface of the substrate holding unit 35, and the position of the other end 62 in the vertical direction can be adjusted. The first adjustment unit 63 b is configured to prevent the substrate holding unit 35 from being displaced in the horizontal direction when adjusting the height of the substrate holding unit 35, and includes the substrate holding unit 35 and the other end 62. It is fastened and fixed with bolts. The second adjusting portion 63a can be switched between a first state where one end portion is fixed on the base 37 and the other end portion 61 is coupled to the substrate holding portion 35 and a second state where the other end portion 61a is not coupled. The position of the end 61 in the vertical direction can be adjusted. As shown in FIG. 7, the second adjusting portion 63 a is configured so that the incompressible fluid filled by driving the piston 107 of the piston portion 121 passes from the piston portion space 105 through the tube 108 to the inner space 102 of the main body portion 120. Move to. As the volume of the incompressible fluid in the internal space 102 is changed by the drive of the piston 107, the diaphragm 103 is deformed, so that the drive unit (the other end) 101 is displaced vertically. Specifications such as “displacement amount of the drive unit 101 with respect to the feed amount of the piston 107” and “stroke” of the second adjustment unit 63a are determined as follows.

  First, the displacement amount of the drive unit 101 with respect to the feed amount of the piston 107 is the sum of the cross-sectional areas of the diaphragm unit 102 and the drive unit 101 (surface viewed from the top of the paper) and the cross-sectional area of the piston 107 (surface viewed from the left of the paper). It is determined by the ratio. The stroke of the drive unit 101 is the product of the stroke of the piston 107 and the displacement amount of the drive unit 101 with respect to the feed amount of the piston 107. Therefore, when the drive unit 101 is positioned with high accuracy, the cross-sectional area of the piston 107 is reduced. By changing the ratio of the area of the diaphragm 103 and the area of the piston part 121, it is possible to determine the positioning accuracy of the first to second adjusting parts 63a and 63b. Further, the upper surfaces of the other end portions of the second adjusting portions 63 a and 63 b are structured to be freely inclined by the diaphragm 103. For example, when the vacuum chuck mechanism disposed at the other end portion 61 is inclined, the upper surface of the second adjustment portion 63 b is inclined by the angle, and the lower surface follows the upper surface of the base 37.

The present embodiment is not limited to this, and any number of mechanisms can be arranged arbitrarily according to the size and shape of the substrate holding part 35 and the base 37 and the number of components.
A vacuum chuck mechanism installed at the other end portion 61 of the second adjustment portion 63 b and capable of coupling the second adjustment portion 63 b to the substrate holding portion 35 is connected to the air control portion 64 via the air pipe 65. Similarly, the substrate holding unit 35 is connected to the air control unit 64 via an air pipe 66 of another system. The height adjustment mechanism 63 of the first to second adjustment units 63 a and 63 b is connected to the drive unit 67. Further, a measuring instrument 68 that measures the height position of the upper surface of the substrate 36 or the substrate holding unit 35 is disposed above the substrate holding unit 35. The air control unit 64, the drive unit 67, and the measuring device 68 are connected to the calculation control unit 99 and can control the adjustment amount of the height adjustment mechanism based on the measurement result of the measuring device 68. The measuring instrument 68 shown in the figure is only required to be able to measure the position of the upper surface of the substrate holding unit 35 or the substrate 36 at each of the locations supported by the support unit 60. The arrangement pitch can be changed freely.

  FIG. 3 shows a flow from measurement to height adjustment when the height of the upper surface of the substrate 36 is adjusted. In addition, each piping and cable connected to the substrate holding part 35, the vacuum chuck mechanism of the other end part 61 of the second adjustment part 63a, and the height adjustment mechanism of the first to second adjustment parts 63a and 63b are illustrated. Absent. First, assuming that the apparatus is being assembled or maintained, the initial state is that the substrate 36 is tilted (state a). In this state a, the vacuum chuck mechanism of the second adjustment unit 63b fixes the back surface of the substrate holding unit 35 in the suction state (first state). The measuring device 68 measures a plurality of points on the upper surface of the substrate 36 placed on the substrate holding unit 35, and the obtained height position information is taken into the calculation control unit 99 (not shown).

  Next, as a step before adjustment, the vacuum chuck mechanism of the second adjustment unit 63a is switched to the atmospheric release state (second state) according to a command from the arithmetic control unit 99 (state b). That is, the substrate holding unit 35 is in a state where the horizontal direction and the vertical direction are fixed only at one point of the other end 62 of the first adjustment unit 63b. In addition, the board | substrate holding | maintenance part 35 can incline on the other end part 62 of the 1st adjustment part 63b as a fulcrum.

  Subsequently, the command value is sent from the calculation control unit 99 to the driving unit 67, and the first to second adjustment units 63a, 63a, The height adjusting mechanism 63b can be driven in conjunction. Therefore, the substrate holding part 35 is Z-displaced to the target position (state c). Here, since the substrate holding portion 35 and the vacuum chuck mechanism at the other end portion 61 of the second adjustment portion 63a are not in a coupled state, the substrate holding portion 35 is applied with a force only for Z displacement. . That is, excessive stress is not applied to the substrate holding part 35.

  After the height adjustment by the first to second adjustment units 63a and 63b is completed, the vacuum chuck mechanism of the second adjustment unit 63a is switched to the coupled state, and the substrate holding unit 35 is fixed (state d). Even if the substrate holding portion 35 is displaced at the moment of fixing by the vacuum chuck, it can be corrected by repeatedly performing the operation. As described above, by repeatedly performing from measurement to height adjustment, the position of the upper surface of the substrate 36 can be displaced to a target position. For example, as shown in FIG. 4, the substrate holding portion 35 is supported by five first to second adjustment portions 63a and 63b of one supporting portion 60, and 12 substrate holding portions 35 are arranged in the horizontal direction. For example, the flatness of the large substrate 36 can be driven.

  FIG. 5 shows a form to which the function of the vacuum chuck mechanism of the second adjustment unit 63a can be applied. The air suction area in the vacuum chuck mechanism is an area of the suction groove 70 dug in a circular shape. The suction air supply to the suction groove is connected to the air suction hole 71 from a piping system (not shown), and is performed from the suction groove surface hole 71a to the suction groove 70. The counterbored holes 72 at the four corners are prepared for use in fastening with a height adjusting mechanism formed in the lower part. An example has been given to the last, but there is a method of widening the area of the suction groove or a method using a magnet if it is necessary to secure a large suction force by expanding the apparatus.

  FIG. 6 shows a mode for securing a larger holding force of the substrate holding unit 35 when the driving acceleration of the substrate stage 30 is increased. In the embodiment of FIG. 6, two magnets 80 and the other end 61 having a vacuum chuck mechanism are configured on the upper surface of the height adjusting mechanism, and two magnet receivers 81 are configured on the lower surface of the substrate holding unit 35 positioned at the upper part. Magnet receiving bases 82 are fastened and fixed respectively. The material of the magnet receiver 81 is a soft magnetic material or a hard magnetic material that attracts the magnet 80 to each other. The magnet 80 and the magnet receiver 81 constitute an electrostatic chuck mechanism.

  In the vacuum chuck state, the upper surface of the vacuum chuck mechanism and the lower surface of the magnet receiving base 82 come into contact as the contact surface 83. At this time, an attractive force acts between the magnets 80 formed on both sides and the magnet receivers 81 facing each other at the top and bottom, and becomes a holding force of the substrate holding part 35. The attractive force can be arbitrarily changed by adjusting the gap between the magnet 80 and the magnet receiver 81. Therefore, it is possible to obtain an optimum suction force according to the driving conditions of the substrate stage 30. When adjusting the height, air is blown from an air piping system connected to a vacuum chuck mechanism. Therefore, the region of the contact surface 83 is in a non-contact state, and it is possible to suppress the occurrence of residual stress due to the height adjustment of the substrate holding part 35.

[Device manufacturing method]
Next, a method for manufacturing a device (semiconductor device, liquid crystal display device, etc.) will be described. A semiconductor device is manufactured through a pre-process for producing an integrated circuit on a wafer and a post-process for completing an integrated circuit chip on the wafer produced in the pre-process as a product. The pre-process includes a step of exposing the wafer coated with the photosensitive agent using the above-described exposure apparatus, and a step of developing the wafer. The post-process includes an assembly process (dicing and bonding) and a packaging process (encapsulation). A liquid crystal display device is manufactured through a process of forming a transparent electrode. The step of forming the transparent electrode includes a step of applying a photosensitive agent to a glass substrate on which a transparent conductive film is deposited, a step of exposing the glass substrate on which the photosensitive agent is applied using the above-described exposure apparatus, and a glass substrate. The process of developing is included. According to the device manufacturing method of the present embodiment, it is possible to manufacture a higher quality device than before. As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to these embodiment, A various deformation | transformation and change are possible within the range of the summary.

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

Claims (5)

A stage device that holds a substrate and is movable in a direction perpendicular to the surface of the substrate,
The foundation,
A substrate holder for holding the substrate;
At least one support unit that is installed on the base and supports the substrate holding unit so that the position of the substrate holding unit in the direction can be changed;
With
Each of the at least one support is
One first adjustment portion having one end portion fixed on the base and the other end portion fixed to the substrate holding portion, the position of the other end portion being adjustable in the direction;
One end fixed on the base, and the other end that can be switched between a first state coupled to the substrate holder and a second state not coupled to the substrate holder, A plurality of second adjustment units capable of individually adjusting the position of the other end in the direction;
While adjusting the position in the direction of at least one other end of the plurality of second adjustment units and the first adjustment unit, all the coupling states of the other end portions of the plurality of second adjustment units are the second. A control unit for controlling the first adjustment unit and the plurality of second adjustment units so as to be in a state;
The stage apparatus characterized by including.   2. The stage apparatus according to claim 1, wherein each second adjustment unit includes at least one of a vacuum chuck mechanism and an electrostatic chuck mechanism that allow other end portions to be coupled to the substrate holding unit. A measuring instrument that measures the position of the upper surface of the substrate holding unit or the upper surface of the substrate held by the substrate holding unit in each of the locations where the substrate holding unit is supported by the at least one supporting unit in the direction; Prepared,
The control unit determines an adjustment amount of a position in the direction of each of the other ends of the first adjustment unit and the second adjustment units based on a measurement result of the measuring instrument, and the plurality of second adjustment units Adjusting the position in the direction of each of the other ends of the first adjustment unit and the plurality of second adjustment units by the determined adjustment amount while maintaining the coupling state of the other end of the second adjustment unit in the second state, 3. The stage apparatus according to claim 1, wherein after completion of the adjustment, the coupling state of all the other end portions of the plurality of second adjustment units is switched to the first state. An exposure apparatus for exposing a substrate,
An exposure apparatus, wherein the substrate is held by the stage apparatus according to any one of claims 1 to 3. A method of manufacturing a device comprising:
A step of exposing the substrate using the exposure apparatus according to claim 4;
Developing the substrate exposed in the step;
A method comprising the steps of:

Images