JP4883810B2 - Stage apparatus, exposure apparatus, and device manufacturing method - Google Patents

Description

  The present invention relates to a stage base applied to a stage apparatus, and more particularly to a stage apparatus having a cooling mechanism connected to a fine movement stage and capable of cooling by circulating a cooling medium. The present invention also relates to an exposure apparatus and a device manufacturing method using such a stage apparatus.

  An exposure apparatus such as a stepper that projects a semiconductor device manufacturing pattern drawn on a mask or reticle onto a wafer is used. Such an exposure apparatus has a function of aligning the reticle and the wafer before performing the exposure process. In general, such alignment includes a step-and-repeat type and a step-and-scan type. A step-and-repeat type exposure apparatus measures a deviation between an original plate such as a reticle on which a pattern to be exposed is drawn and an exposed object (substrate) such as a wafer, and repeats the exposed object based on the measurement result. Step and expose. A step-and-scan type exposure apparatus performs exposure by relatively moving an original plate and an object to be exposed. These exposure apparatuses are required to position a wafer stage that moves while holding an object to be exposed (wafer) with extremely high accuracy from the viewpoint of resolution and overlay accuracy. In recent years, it has been desired to increase the positioning speed in order to improve productivity.

  FIG. 7 is a perspective view showing a conventional wafer stage in the exposure apparatus. In FIG. 7, a Y stage 54 as a moving mechanism in the Y direction is placed on a stage surface plate 55. On the Y stage 54, an X stage 51 as a moving mechanism in the X direction is placed. In this way, the XY stage 56 is configured by the Y stage 54 and the X stage 51.

  FIG. 8 is a schematic diagram showing the configuration of the XY stage. The stage surface plate 55 has a reference surface with a smooth upper surface. The XY stage 56 includes a Y stage 54 (54a, 54b, 54c, 54d) as a moving body and an X stage 51 as a moving body. A fixed guide 52 is provided in the horizontal direction (Y-axis direction) of the Y stage 54. In the horizontal direction of the X stage 51 (X axis direction), the vertical direction of the X stage 51 (Z axis direction), the horizontal direction of the Y stage 54 (Y axis direction), and the vertical direction of the Y stage 54, porous static A compressed air bearing is provided to guide each of these stages.

  The Y stage 54 floats from the surface plate 55 by supplying air to these static pressure air bearings, and moves along the fixed guide 52 provided on one side by two drive actuators 54c arranged on both sides thereof in the Y direction. Move to. The X stage 51 floats from the surface plate 55 in the same manner as the Y stage 54 by supplying air to these static pressure air bearings, and moves in the X direction by the drive actuator 51c using the side surface 54b of the Y stage 54 as a horizontal guide. To do. At this time, the X stage 51 and the Y stage 54 are adjusted so as to always have a fixed posture by a plurality of pressurizing magnet units (not shown).

  FIG. 9 is a schematic diagram showing the configuration of fine movement stage 90. Below the fine movement stage 90, an XY stage 56 (see FIG. 8) having a reference for applying a thrust or suction force to the fine movement stage 90 is disposed. The fine movement stage 90 is mounted in a non-contact manner on a stage base 50 ′ provided on the X stage 51. The XY stage 56 includes linear motors 11, 12, and 13 that finely control the attitude of the fine movement stage 90 with respect to the reference plane, and cylindrical electromagnet units 21 and 22 that transmit acceleration in the XY direction to the fine movement stage 90. 23. The fine movement stage 90 includes a self-weight compensation mechanism 3 for supporting the self-weight.

  With the above configuration, thrust can be applied from the XY stage 56 to the fine movement stage 90 by the linear motors 11, 12, and 13, and a large attractive force can be applied in the XY direction by the electromagnet units 21, 22, and 23.

  As described above, when the fine movement stage 90 is supported in a non-contact manner with respect to the XY stage 56, the linear motors 11, 12, and 13 are required to have performance sufficient to accelerate the fine movement stage 90 with a desired acceleration. Therefore, the linear motors 11, 12, and 13 are expected to generate heat when the fine movement stage 90 is driven. Therefore, the linear motors 11, 12, and 13 are provided with a cooling mechanism. With this cooling mechanism, the heat generated from the linear motors 11, 12, and 13 is prevented from leaking to the outside.

  FIG. 10 shows a linear motor coil 113 disposed on the support surface 100 ′ of the stage base 50 ′ for driving the fine movement stage 90, a component 1 having a cooling mechanism for cooling the linear motor coil 113, FIG. The component 1 is generally configured to cover the linear motor coil 113 with a jacket 112 and supply a cooling medium using a resin tube 111 inside the jacket 112. With such a configuration, the component 1 can cool the linear motor coil 113.

Similarly, in the electromagnet units 21, 22, and 23 shown in FIG. 9, when the XY stage 56 of FIGS. 7 and 8 is driven, a large attractive force is applied to the fine movement stage 90. The coil is expected to generate heat. Therefore, the coils of the electromagnet units 21, 22, and 23 can be prevented from leaking heat generated by these coils by providing a cooling mechanism in the same manner as the linear motor 1. As in the case of the linear motor described above, such a cooling mechanism is also generally configured to cover a coil with a jacket and supply a cooling medium using a resin tube 111 inside the jacket.
Japanese Patent No. 3145355

However, a conventional stage apparatus that distributes and supplies a cooling medium using a resin tube with respect to a component having a cooling mechanism connected to a fine movement stage has the following problems.
(1) If the resin tube is fixed and arranged on the stage base so that the resin tube does not vibrate, the dimension of the mounting portion to which the resin tube is attached increases, and there is a concern about interference with surrounding components and an increase in mass.
(2) When the resin tube is drawn around, disturbance increases, which hinders highly accurate positioning.

  When the stage apparatus is placed in a vacuum chamber and used in a vacuum environment or a reduced pressure environment, the resin tube generates a large amount of outgas. There is concern about a decrease in the degree of vacuum.

  This invention is made | formed in view of said problem, and it aims at keeping down the usage-amount of the resin tube for supplying a cooling medium to the components which have a cooling part low.

The present invention relates to a stage apparatus , comprising: a stage; a plate that supports the stage; and a cooling unit that is disposed on a surface of the plate and that cools the object to be cooled with a refrigerant. And a through hole communicating with the coolant channel is provided on a surface on which the cooling unit is disposed, and the cooling unit is connected to the cooling unit via the coolant channel and the through hole. The refrigerant is supplied or the refrigerant is discharged from the cooling unit .

  ADVANTAGE OF THE INVENTION According to this invention, the usage-amount of the resin tube for supplying a cooling medium to the components which have a cooling part can be restrained low.

  The present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a view showing a stage base 50 according to a preferred embodiment of the present invention and a component 1 having a cooling unit connected to the stage base 50. FIG. 1 is an exploded view showing a linear motor stator jacket as an example of a component 1 having a cooling unit.

  As shown in FIG. 1, the stage base 50 is configured as one structure by fastening two structures, a base plate 50a and a base plate 50b, with fasteners such as bolts. The base plate 50a and the base plate 50 constitute a plate that supports the stage. Each of the base plate 50a and the base plate 50 constitutes a first structure and a second structure of the plate. Further, the base plate 50b has a support surface 100 that movably supports the fine movement stage 90 having a fine stroke shown in FIG. The stage apparatus according to the present embodiment is schematically obtained by partially changing the configuration of the stage apparatus shown in FIGS. That is, in the stage apparatus according to the present embodiment, the stage base 50 shown in FIG. 1 is provided on the X stage 51 of FIG. 8 instead of the stage base 50 ′. As a material of the stage base 50, it is preferable to use ceramics for light weight and high rigidity. However, the material is not limited to this, and other materials such as metal may be used.

  A groove 41 is dug in the surface of the base plate 50a. By fastening the base plate 50a and the base plate 50b, an internal flow path for distributing and supplying the cooling medium 42 is formed between the groove 41 and the base plate 50b. The internal flow path constitutes a flow path for refrigerant that is disposed so as to pass through the plate and into the components described later. A seal groove 44 surrounding the outer periphery of the groove 41 is dug in the base plate 50a. By fitting an O-ring (not shown) as a seal member into the seal groove 44, it is possible to prevent the cooling medium circulating in the groove 41 as an internal flow path from leaking outside the stage base 50. In addition, as such a sealing member, it is not limited to an O-ring, For example, you may use a gasket and an adhesive agent. Further, fine movement stage 90 is preferably configured to have three or more degrees of freedom.

  On the support surface 100 (on the plate) of the stage base 50, there are a linear motor coil 113 for driving the fine movement stage 90 of FIG. 9 and a component 1 having a cooling mechanism for cooling the linear motor coil 113. Has been placed. The component 1 is disposed on the support surface 100 so as to cover the linear motor coil 113. The component 1 is connected to the internal flow path via an O-ring as a seal member.

  A seal groove 61 is provided in the base plate 50b. By providing a seal member such as an O-ring (not shown) in the seal groove 61 and fastening a component (for example, a linear motor stator jacket) 1 having a cooling portion to the stage base 50, the cooling medium leaks to the outside. Can be prevented. A through hole 61 ′ communicating with the groove 41 is provided inside the seal groove 61. By connecting the component 1 disposed on the support surface 100 and the through hole 61 ′, the cooling medium can be directly supplied to the component 1 through the groove 41. For this reason, the resin tube 111 of FIG. 10 used for connecting the stage base 50 and the component 1 becomes unnecessary.

  In the present embodiment, the seal groove 61 is provided in the base plate 50b, but is not limited thereto, and may be provided in the base plate 50b. In the present embodiment, the groove 41 is provided in the base plate 50a. However, the groove 41 is not limited thereto, and may be provided in at least one of the base plate 50a and the base plate 50b constituting the stage base 50. Similarly, the seal groove 44 is provided on the same member (in this embodiment, the base plate 50a) as the member provided with the groove 41, but is not limited to this, and the base plate 50a and the base plate 50b are not limited thereto. What is necessary is just to provide in at least one. Moreover, in this embodiment, the flow path is formed in the inside by fastening two flat plates. However, the present invention is not limited to this, and the groove 41 is formed inside the single flat plate. Also good. The seal groove 44 is disposed so as to surround the internal flow path.

Hereinafter, a configuration example of a stage base according to a preferred embodiment of the present invention will be described with reference to FIGS. 2, 4, and 5. 2, FIG. 4 and FIG. 5 are plan views of the base plate 50a shown in FIG.
[First configuration example]
First, a first configuration example according to a preferred embodiment of the present invention will be described with reference to FIG. On the surface of the base plate 50a, a groove 41 (shaded portion) as an internal flow path is dug. The inlet 41a and the outlet 41b are an inlet and an outlet for supplying a cooling medium to the groove 41.
The groove 41 as an internal flow path is constituted by a plurality of pipes. The plurality of pipes can be configured such that the pipe resistances are substantially the same. That is, the groove 41 is configured so that the pipe resistance when the cooling medium flows from the inlet 41a through the groove 41 in the stage base 50 to the outlet 41b through the component 1 is substantially equal in each pipe. Can be done. The seal groove 44 is dug outside the groove 41 and prevents the cooling medium flowing through the groove 41 from leaking outside the stage base 50 using a seal member such as an O-ring.

  The screw holes 45 and 46 are provided to fasten the base plate 50a and the base plate 50b of FIG. 1 with fasteners such as bolts. When applying a force to the sealing member such as the O-ring, it is desirable to provide screw hole portions 45 and 46 on both sides of the O-ring in order to suppress the stress acting on the ceramic plate 50b.

  FIG. 3 is an enlarged view of the vicinity of the screw hole 45 provided inside the seal groove 44. The screw hole portion 45 includes a screw hole 45b and a groove 45a (shaded portion) for a seal member such as an O-ring. Inside the seal groove 44, it is conceivable that the cooling medium flows into the gap between the base plates 50a and 50b due to the internal pressure of the cooling medium supplied to the groove 41. For this reason, a sealing groove 45a is provided on the outer periphery of the screw hole 45b provided inside the seal groove 44 in order to prevent the cooling medium from leaking from the screw hole 45b to the outside of the stage base. It is desirable to seal with a sealing member such as.

The stage base in the first configuration example has at least the following features.
(1) By supplying a cooling medium directly to a part having a cooling part used for a linear motor or the like through an internal flow path, interference with surrounding parts due to the resin tube being drawn, and high accuracy An increase in disturbance that hinders accurate positioning can be suppressed.
(2) In addition, by providing grooves in the stage base so that the pipe resistance of the internal flow path when supplying the cooling medium from the inlet to the stage base to the part having the cooling unit is substantially equal, The member can be cooled evenly.

In this configuration example, the screw hole portions 45 and 46 for fastening the stage base 50 are provided on the ceramic plate 50a side. However, the present invention is not limited to this, and may be provided on the ceramic plate 50b side. .
[Second configuration example]
FIG. 4 is a diagram exemplarily showing a second configuration example obtained by modifying the first configuration example shown in FIG. 2. In this configuration example, the same reference numerals are assigned to the same components as those in the first configuration example. In the configuration example of FIG. 2, the base plate 50 a and the base plate 50 b are fixed by fastening with fasteners such as bolts in the screw hole portions 45 and 46 provided on both sides of the seal groove 44. In the configuration example of FIG. 4, considering that the stage base is used in a vacuum environment or a reduced pressure environment, in addition to the configuration of FIG. Adhesive grooves (adhesive pools) 47 are provided for filling (not shown). Accordingly, the second configuration example has the following features in addition to the features (1) and (2) of the first configuration example.
(3) When the cooling medium supplied to the internal flow path flows into the region of the gap between the base plates 50a and 50b other than the internal flow path, the base plates 50a and 50b can be more reliably fixed. At that time, the area where the differential pressure acts (area where the cooling medium can flow in) is reduced by the adhesive pool against the force generated by the differential pressure between the cooling medium and the outside of the stage base (vacuum or reduced pressure atmosphere). Let Therefore, the force due to the differential pressure can be reduced. Further, the stress concentration in the screw hole 45 that fastens the base plates 50a and 50b can be reduced.
[Third configuration example]
FIG. 5 is a diagram exemplarily showing a third configuration example obtained by modifying the second configuration example shown in FIG. 4. In this configuration example, the same reference numerals are assigned to the same components as those in the second configuration example. In the present configuration example, in addition to the configuration of FIG. 4, a screw portion 48 is provided inside the adhesive pool 47. FIG. 6 is an enlarged view of the adhesive pool 47 and the threaded portion 48 therein. The screw part 48 fastens the base plates 50a and 50b with fasteners such as bolts. The seal groove 48a (shaded portion) is a groove for a seal member such as an O-ring provided to prevent the cooling medium from leaking from the screw hole 48b to the outside of the stage base. The partition wall 48c is a wall provided between the seal groove 48a and the adhesive pool 47, and can more effectively suppress leakage of the cooling medium to the outside.

In addition to the configuration of FIG. 4, the present configuration example has the following features in addition to the features (1) to (3) of the first and second configuration examples by including the above-described structure.
(4) By fastening the inside of the adhesive pool 47 with a fastener such as a bolt, a shearing force acting on the adhesive by the force generated by the differential pressure between the cooling medium and the outside of the stage base (vacuum or reduced pressure atmosphere) Can be relaxed and the adhesive can be prevented from peeling off.

  FIG. 11 is a drawing schematically showing a configuration of an exposure apparatus incorporating a stage apparatus according to a preferred embodiment of the present invention. In the example shown in FIG. 11, the above-described stage apparatus is mounted as a wafer stage 700, and a mask stage 500 is mounted thereon. In mask stage 500, the mask is held by a chuck provided thereon, and in wafer stage 700, the wafer is held by a chuck provided in fine movement stage 90. The mask is illuminated by the illumination optical system 601, and an image of the pattern formed on the mask is projected and transferred onto the wafer via the projection optical system 602. In this way, this exposure apparatus can perform the exposure operation by positioning the positioning object (wafer) using the stage apparatus according to the preferred embodiment of the present invention. The photosensitive layer on the wafer as the substrate to which the pattern has been transferred is developed to produce a semiconductor device. This exposure apparatus can be applied to a known manufacturing process of a semiconductor device.

  Next, a device manufacturing method using the exposure apparatus will be described. In that case, the device is manufactured through a process of forming a pattern on the substrate using the above-described exposure system and other known processes. The device can be a semiconductor integrated circuit element, a liquid crystal display element, or the like. The substrate can be a wafer, a glass plate, or the like. The known processes are, for example, processes such as oxidation, film formation, vapor deposition, doping, planarization, dicing, bonding, and packaging.

It is a figure which shows the cooling base applied to the stage base and fine movement stage which concern on suitable embodiment of this invention. It is a figure which shows the 1st structural example which concerns on suitable embodiment of this invention. It is an enlarged view of the screw hole part vicinity provided inside the seal groove. It is a figure which shows the 2nd structural example which concerns on suitable embodiment of this invention. It is a figure which shows the 3rd structural example which concerns on suitable embodiment of this invention. It is an enlarged view of an adhesion pool and a screw part inside. It is a perspective view which shows the wafer stage applied to the conventional exposure apparatus. It is the schematic which shows the structure of the conventional XY stage. It is the schematic which shows the structure of the conventional fine movement stage. It is the schematic which shows the conventional stage base and the cooling unit applied to a fine movement stage. 1 is a conceptual diagram of an exposure apparatus to which a stage apparatus according to a preferred embodiment of the present invention is applied.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Parts 11, 12, 13 which have a cooling part Linear motor 111 Resin tube 112 Jacket 113 Linear motor coils 21, 22, 23 Electromagnet unit 3 Self-weight compensation mechanism 41 Groove (internal flow path)
41a Inlet 41b Outlet 42 Cooling medium 44 Seal groove 45, 46 Screw hole portion 47 Adhesive reservoir 48 Screw portion 50, 50 'Stage base 50a, 50b Base plate 51 XY stage 61 Seal groove 61' Through hole 90 Fine movement stage 100 Support surface

Claims (12)

Stage,
And a plate for supporting the stage,
A cooling object disposed on the surface of the plate;
A cooling unit disposed on a surface of the plate and cooling the object to be cooled with a refrigerant ;
With
The plate has a coolant channel formed therein, and a through-hole communicating with the coolant channel is provided on a surface on which the cooling unit is disposed, and the plate includes the coolant channel and the through hole. The stage device is configured such that the coolant is supplied to the cooling unit or is discharged from the cooling unit . The cooling object is a coil for driving the stage ,
The cooling unit, the stage apparatus according to claim 1, characterized in that said not covering the coil, a cooling jacket flow path is formed to flow a coolant therein. The said refrigerant | coolant flow path is comprised by the some pipeline, and this pipeline is comprised so that the pipeline resistance may become substantially the same, respectively. Stage equipment . The stage apparatus according to any one of claims 1 to 3, wherein the cooling unit is connected to the refrigerant flow path via a seal member. The stage apparatus according to claim 4, wherein the seal member includes an O-ring, a gasket, and an adhesive. The plate has a first structure in which a groove is formed, and a second structure fixed to the first structure, and the inner surface of the groove in the first structure and the surface of the second structure The stage device according to claim 1 , wherein the refrigerant flow path is formed . A seal member is provided between the first structure and the second structure so as to surround the outside of the coolant channel, and the inside and outside of the seal member are fastened by a fastener. The stage apparatus according to claim 6. The second structure is fixed to the first structure with an adhesive , and the first structure or the second structure further includes an adhesive groove filled with an adhesive. Or the stage apparatus of Claim 7. The stage apparatus according to claim 8, wherein the inside of the adhesive groove is fastened by a fastener. A coarse movement stage that moves with the plate mounted thereon,
The stage apparatus according to any one of claims 1 to 9 , wherein the fine movement stage as the stage is driven with at least three degrees of freedom with respect to the coarse movement stage . An exposure apparatus that positions an object to be positioned and executes an exposure operation using the stage apparatus according to claim 10 . Using the exposure apparatus according to claim 11 to transfer a pattern to a substrate;
Developing the substrate;
A device manufacturing method comprising:

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