JP2005043021A - Air conditioner, position sensor and exposure device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air conditioner and the like capable of supplying air conditioned to be at a predetermined temperature to a space to be air-conditioned at an even wind speed even under a condition that an external form is limited. <P>SOLUTION: The air conditioner is equipped with a first air pressure chamber 11 for distributing temperature-controlled air supplied via an air flow-in port 2 along Y direction, a second air pressure chamber 12 for distributing the temperature-controlled air passed through the first air pressure chamber 11 in X direction and a third air pressure chamber 12 located in Z direction to the second air pressure chamber 12 between the second air pressure chamber 12 and a blow-out face 16 and the blow-out face 16 supplies the temperature-conditioned air to the air-conditioned space in a manner widely spreading to the space. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an air conditioner that supplies a gas adjusted to a predetermined temperature to an air-conditioned space, a position measuring device that includes the air conditioner, and an exposure apparatus that includes the position measuring device.

  In order to manufacture semiconductor devices, liquid crystal display devices, image pickup devices, thin film magnetic heads, and other fine devices, a pattern formed on a mask or reticle (hereinafter collectively referred to as a mask) is used as a wafer or glass plate. An exposure apparatus that transfers onto a substrate such as the like is used. Various exposure apparatuses have been devised in the past, but in recent years, step-and-repeat reduction projection exposure apparatuses (steppers) and step-and-scan exposure apparatuses are often used. Yes.

  In the above stepper, the substrate is placed on a substrate stage that is movable in two dimensions, and the substrate is stepped (stepped) by this substrate stage, and a reduced image of the mask pattern is applied to each shot area on the substrate. An exposure apparatus that sequentially repeats the batch exposure operation. In addition, a step-and-scan type exposure apparatus irradiates a mask stage on which a mask is placed and a substrate stage on which a substrate is placed with respect to the projection optical system while irradiating the mask with slit-shaped exposure light. Then, a part of the pattern formed on the mask is sequentially transferred to the shot area of the substrate while being synchronously scanned with each other, and when the pattern transfer for one shot area is completed, the substrate is stepped to transfer the pattern to the other shot area. It is an exposure apparatus to be performed.

  Since both the above stepper and step-and-scan type exposure apparatuses need to move the substrate stage accurately, a laser interferometer for detecting the position information of the substrate stage with high accuracy is provided. Further, since the step-and-scan type exposure apparatus moves the mask stage in synchronization with the substrate stage, a laser interferometer for detecting position information of the mask stage is also provided. A laser interferometer irradiates a movable mirror provided on a substrate stage or a mask stage with high-coherent measurement light such as laser light, and irradiates a fixed mirror with a fixed position with high-coherent reference light. The position information of the substrate stage or the mask stage is detected by detecting the interference light obtained by causing the reflected measurement light and the reference light reflected by the fixed mirror to interfere with each other. Has high resolution.

In the laser interferometer, when the ambient temperature fluctuates or the air fluctuates, the detection accuracy deteriorates because the optical path length of the measurement light or the optical path length of the reference light changes. In order to prevent such deterioration in detection accuracy and maintain high detection accuracy, an air conditioner is used that maintains the entire optical path of measurement light and reference light at a uniform temperature and at a uniform flow rate. For example, a laser interferometer is provided in two orthogonal directions in the moving plane for the substrate stage of the above stepper, but in order to air-condition the optical paths of the measurement light and the reference light emitted from each laser interferometer An air conditioner is provided that blows out air-conditioned gas from the side of each optical path in a fan shape and distributes the gas to each optical path. Moreover, as shown in the following Patent Document 1, an air conditioner is provided that covers the optical paths of the measurement light and the reference light with a cylindrical member and air-conditions the inside of the cylindrical member.
JP-A-5-283313

  By the way, an air conditioner that blows out air-conditioned gas in a fan shape is incident on the optical path of the measurement light and the reference light at various angles, and the distribution of the wind speed of the gas occurs depending on the blowing direction. There is a problem that the air-conditioner cannot be air-conditioned and the detection accuracy of the laser interferometer may be lowered. In addition, an air conditioner that covers the optical path with a cylindrical member and air-conditions the inside thereof is difficult to realize mechanically for the following reasons, and it is difficult to maintain the inside of the cylindrical member at a uniform temperature and a uniform wind speed. There was a problem that there was.

  That is, when the substrate stage moves in a direction parallel to the optical path of the measurement light, the optical path length of the measurement light changes according to the movement distance of the substrate stage, so that the optical path length changes due to the movement of the substrate stage. When the mechanism for expanding and contracting the cylindrical member and the substrate stage move in a direction intersecting the optical path of the measuring light, the optical path length of the measuring light does not change, but the cylindrical member remains the substrate even if the substrate stage moves. This is because a mechanism that does not move in the moving direction of the stage is required.

  The exposure apparatus has a projection optical system disposed above the substrate stage, and an alignment sensor for measuring position information of a mark (alignment mark) formed on the substrate on the side of the projection optical system and the vertical direction of the substrate. A focus detection system for detecting the position and orientation is arranged. Further, the distance between the laser interferometer and the stage is set to be long according to the maximum amount of movement of the substrate stage. For this reason, the air conditioner must be thin in the vertical direction and long in the direction of the optical path of the measurement light, and the outer shape is greatly limited.

  The present invention has been made in view of the above circumstances, and an air conditioner capable of supplying a gas adjusted to a predetermined temperature to an air-conditioned space at a uniform wind speed even under conditions where the outer shape is restricted, It aims at providing a position measuring device provided with an air-conditioner, and the position measuring device concerned.

In order to solve the above problems, an air conditioner according to the present invention includes an air inlet (2) for the gas in an air conditioner (1) that supplies a gas adjusted to a predetermined temperature to an air-conditioned space (AP), An air guide member (16) for supplying the gas to the air-conditioned space, and a plurality of pressure chambers (11 to 13) provided between the inlet and the air guide member and communicating with each other. It is characterized by that.
According to the present invention, the wind speed is made uniform by passing through the air pressure chamber provided with a plurality of gases adjusted to a predetermined temperature flowing in from the inlet, and this gas is supplied from the air guide member to the air-conditioned space. Therefore, the gas adjusted to a predetermined temperature can be supplied to the air-conditioned space at a uniform wind speed.
In order to solve the above-described problem, the position measuring device of the present invention transmits a light beam to a movable body (21, 30) movable in a predetermined direction and a reflecting portion (22, 31) provided on the movable body. In a position measuring device including an interferometer (24, 32) that irradiates and measures the position of the movable body, an air guide member (16) that blows a gas adjusted to a predetermined temperature toward the light beam. And an air conditioner (27, 36) for supplying the gas so that the gas sent from the air guide member spreads toward the light beam.
According to this invention, since the gas adjusted to a predetermined temperature is supplied from the air guide member provided in the air conditioner so as to spread toward the light beam, air having different temperatures is caught in the optical path of the light beam. As a result, the position information of the movable body can be measured with high accuracy. Further, the apparatus can be reduced in size by supplying the gas adjusted to a predetermined temperature so as to spread toward the light beam.
The exposure apparatus of the present invention further includes a mask stage (21) for holding a mask (R) and a substrate stage (30) for holding a substrate (W), and a pattern formed on the mask is placed on the substrate. In the exposure apparatus for transferring to, the position measurement apparatus described above is provided that measures position information of at least one of the mask stage and the substrate stage as position information of the movable body.
According to the present invention, since the position measurement device that measures the position information of at least one of the mask stage and the substrate stage is provided with a small size and high accuracy, a fine pattern can be accurately formed on the substrate.

According to the present invention, the wind speed is made uniform through the pressure chamber provided with a plurality of gases adjusted to a predetermined temperature flowing in from the inlet, and this gas is supplied from the wind guide member to the air-conditioned space. Therefore, there is an effect that the gas adjusted to a predetermined temperature can be supplied to the air-conditioned space at a uniform wind speed.
In addition, according to the present invention, since the gas adjusted to a predetermined temperature is supplied from the air guide member provided in the air conditioner so as to spread toward the light beam, the air with different temperatures is in the optical path of the light beam. As a result, the position information of the movable body can be measured with high accuracy. Moreover, there is an effect that the apparatus can be miniaturized by supplying the gas adjusted to a predetermined temperature so as to spread toward the light beam.
Furthermore, according to the present invention, since the position measurement device that measures the position information of at least one of the mask stage and the substrate stage is provided with a small size and high accuracy, a fine pattern can be accurately formed on the substrate. There is an effect that can be done.

  Hereinafter, an air conditioner, a position measuring device, and an exposure device according to an embodiment of the present invention will be described in detail with reference to the drawings.

[Air conditioner]
FIG. 1 is a top perspective view showing a configuration of an air conditioner according to an embodiment of the present invention. 2 is a cross-sectional arrow view along the line AA in FIG. 1, and FIG. 3 is a cross-sectional arrow view along the line BB in FIG. In the following description, an XYZ rectangular coordinate system is set as shown in FIGS. 1 to 3, and the positional relationship of each member will be described with reference to the XYZ rectangular coordinate system. In the XYZ coordinate system set in the present embodiment, it is assumed that the XY plane is set to a plane parallel to the horizontal plane and the Z axis is set in the vertical upward direction.

  As shown in FIGS. 1-3, the external shape of the air conditioner 1 of this embodiment is a flat substantially rectangular parallelepiped shape with a long length in the Y direction and a short width in the Z direction. On one side of the air conditioner 1 (in the example shown in FIGS. 1 and 2, the surface located on the −X direction side of the air conditioner 1), the temperature discharged from a blower (not shown) was adjusted to be constant. An air inlet 2 is provided as an inlet through which air (gas) (hereinafter referred to as temperature-controlled air) flows, and the air conditioner 1 has a flow velocity (speed) of the temperature-controlled air flowing from the air inlet 2. To flow out into the air-conditioned space AP. The cross-sectional shape of the air inlet 2 is, for example, a circular shape or a rectangular shape. As shown in FIGS. 1 to 3, in the present embodiment, for example, the optical path LP of the measurement light emitted from the laser interferometer is arranged in the air-conditioned space AP so as to be parallel to the Y axis. .

  A plurality of pressure chambers communicating with each other are provided inside the air conditioner 1 in order to adjust the pressure of the temperature-controlled air flowing from the air inlet 2 and to equalize the flow velocity. In the example shown in FIGS. 1 and 2, three atmospheric pressure chambers, a first atmospheric pressure chamber 11, a second atmospheric pressure chamber 12, and a third atmospheric pressure chamber 13 are provided. The first air pressure chamber 11 is a pressure air chamber extending in the Y direction and provided in communication with the air inlet 2, and the length in the Z direction is set to be approximately the same as the height in the Z direction of the air conditioner 1. The temperature-controlled air flowing in from the air inlet 2 is distributed along the Y direction (direction along the optical path LP).

  The second atmospheric pressure chamber 12 is set to have a length in the Y direction equal to the length of the first atmospheric pressure chamber in the Y direction, is positioned in the X direction with respect to the first atmospheric pressure chamber 11, and the length in the Z direction is the first atmospheric pressure. The pressure chamber is set shorter than the chamber 11 and distributes the temperature-controlled air via the first pressure chamber 11 along the X direction (direction intersecting the direction along the optical path LP). The length in the X direction of the second atmospheric pressure chamber 12 is set to be shorter than the length in the Y direction of the first atmospheric pressure chamber 11. This is to shorten the length of the air conditioner 1 in the X direction. The third atmospheric pressure chamber 13 is set to have a length in the Y direction equal to the length of the first atmospheric pressure chamber 11 and the second atmospheric pressure chamber 12 in the Y direction, and is located in the −Z direction with respect to the second atmospheric pressure chamber 12. It is.

  The first atmospheric pressure chamber 11 and the second atmospheric pressure chamber 12 are partitioned by a pressure loss sheet 14 as a pressure equalizing member, and the second atmospheric pressure chamber 12 and the third atmospheric pressure chamber 13 are separated by a pressure equalizing member and It is partitioned by a temperature stabilization flow path 15 as a temperature control member, and the third atmospheric pressure chamber 13 and the air-conditioned space AP are partitioned by a temperature-controlled air blowing surface 16 as a wind guide member. The pressure-loss sheet 14 is a mesh-like plate-like member or a plate-like member in which a large number of punch holes are formed. In order to prevent contamination of the air-conditioning air, it is preferable to use a Teflon (registered trademark) sheet or a stainless plate member. The pressure loss sheet 14 is provided to reduce the nonuniformity of the wind speed by reducing the dynamic pressure of the temperature-controlled air flowing from the air inlet 2. Note that a controller for controlling the temperature of the temperature stabilization flow path 15 is not shown.

  The temperature stabilization flow path 15 is configured by arranging a plurality of fins maintained at a constant temperature by a temperature-controlled refrigerant at intervals of about 1 to several millimeters. By passing the temperature adjustment air between the fins provided in the temperature stabilization flow path 15, the temperature of the temperature adjustment air can be adjusted with higher accuracy. In addition to controlling the temperature of the temperature-controlled air that passes therethrough, the temperature stabilizing flow channel 15 makes the temperature-controlled air from the second atmospheric pressure chamber 12 laminarize to have directivity in the blowing direction, and pressure loss in the XY plane. It is also used to make the (pressure loss) variation uniform. In addition, as the gap between the fins provided in the temperature stabilization flow path 15 is narrowed and the length of the fins in the Z direction is increased, the temperature stability and controllability increase, but the pressure loss increases.

  Further, the temperature stabilization flow path 15 is supported in a state of being sandwiched between support members 17 and 18 provided in the −X direction and the + X direction, respectively, but in the + Z direction on the upper surface of the temperature stabilization flow path 15. The position is supported so that the position of the upper surface of the support members 17 and 18 in the + Z direction coincides, that is, no step is generated between the temperature stabilization flow path 15 and the support members 17 and 18. This is because the temperature-controlled air that has flowed into the second atmospheric pressure chamber 12 through the pressure-loss sheet 14 due to a step between the temperature stabilization flow path 15 and the support members 17 and 18 generates a vortex, partially in the −Z direction. This is to prevent the pressure from decreasing. By taking such a measure, the temperature-controlled air blowing from the temperature stabilization flow path 15 to the third atmospheric pressure chamber 13 becomes substantially uniform.

  Referring to FIG. 2, the length of the second pressure chamber 12 in the Z direction is set to be shorter than the length of the first pressure chamber 11 in the Z direction, and one of the wall surfaces of the first pressure chamber 11 has a pressure loss. It is comprised from the sheet | seat 14 and the supporting member 17 as a pressure reduction wall. For this reason, part of the flow of the temperature-controlled air flowing in from the air inlet 2 collides with the support member 17, and this also reduces the dynamic pressure of the temperature-controlled air flowing in from the air inlet 2. With this configuration, the dynamic pressure of the temperature-controlled air can be reduced without greatly increasing the total pressure loss of the air conditioner 1. Thereby, it becomes possible to use a smaller air blower that supplies air-conditioned air to the air conditioner 1 and that has a lower air blowing capacity.

  The temperature-controlled air blowing surface 16 that divides the third atmospheric pressure chamber 13 and the air-conditioned space AP is configured so that the temperature-controlled air via the third atmospheric pressure chamber 13 is spread and supplied toward the air-conditioned space AP. Yes. Specifically, for example, as shown in FIG. 2, the shape along the X direction is configured with a curvature such that the shape along the X direction is convex in the −Z direction, and the shape along the Y direction is −Z as shown in FIG. It is configured with a curvature so as to have a convex shape in the direction. The blowing surface 16 is formed of a net member similar to the pressure loss sheet 14 that partitions the first atmospheric pressure chamber 11 and the second atmospheric pressure chamber 12. The blowing surface 16 does not necessarily have to be formed in a curved surface, and only the end portions (both ends in the X direction and both ends in the Y direction) need only be formed in a curved shape.

  In this way, the blowout surface 16 is configured to supply the temperature-controlled air to the air-conditioned space AP so as to be supplied to the air-conditioned space AP at the end of the temperature-controlled air supplied to the air-conditioned space AP. This is to prevent disturbance of the flow velocity as much as possible and to realize downsizing. That is, generally, when there is a fluid flow in one direction, a gas or the like existing around the fluid is entrained in the fluid flow. This entrained gas disturbs the fluid flow. In order to prevent this turbulence, the flow should be made as thick as possible so that the influence of the entrainment hardly reaches the center of the flow.

  However, when this concept is applied to the air conditioner 1 of the present embodiment, the length in the X direction and the length in the Y direction are required to some extent, leading to an increase in the size of the device. Therefore, in this embodiment, the influence of the end portion is reduced by supplying the temperature-controlled air so as to spread to the air-conditioned space AP, thereby realizing downsizing of the apparatus.

  Next, operation | movement of the air conditioner 1 by one Embodiment of this invention in the said structure is demonstrated. Temperature-controlled air discharged from a blower (not shown) and adjusted to a predetermined temperature is introduced into the air conditioner 1 from the air inlet 2. The introduced temperature-controlled air flows into the first atmospheric pressure chamber 11 and collides with the pressure loss sheet 14 and the support member 17 to reduce the dynamic pressure, and is distributed in the Y direction (direction along the optical path LP). Here, since the first atmospheric pressure chamber 11 and the second atmospheric pressure chamber 12 are partitioned by the pressure loss sheet 14, the temperature-controlled air is supplied to the first atmospheric pressure chamber 11 until the inside of the first atmospheric pressure chamber 11 reaches a certain pressure. To charge.

  Due to this action, the temperature control air filled in the first pressure chamber 11 has a substantially uniform pressure distribution along the Y direction, and the temperature control air flowing through the pressure loss sheet 14 and flowing into the second pressure chamber 12 is adjusted to the wind speed ( The air volume is almost constant regardless of the position in the Y direction. The temperature-controlled air that has flowed into the second atmospheric pressure chamber 12 is distributed in the X direction (the direction that intersects the direction along the optical path LP). In the present embodiment, the temperature stabilization flow path 15 is provided between the second atmospheric pressure chamber 12 and the third atmospheric pressure chamber 13, and the blowing surface 16 is provided between the third atmospheric pressure chamber 13 and the air-conditioned space AP. Since the pressure loss of the blowing surface 16 is high, the temperature control air is filled in the second atmospheric pressure chamber 12 like the first atmospheric pressure chamber 11. Thereby, temperature control air spreads uniformly also about a X direction.

  Here, at the bottom of the second atmospheric pressure chamber 12, it is set so that no step is generated between the temperature stabilization flow path 15 and the support members 17 and 18. As a result, the temperature-controlled air that has flowed into the second atmospheric pressure chamber 12 from the first atmospheric pressure chamber 11 spreads in the second atmospheric pressure chamber 12 without creating vortices in the second atmospheric pressure chamber 12, so that the temperature stabilization flow is more uniform. Temperature-controlled air can be supplied to the path 15. When the temperature-controlled air flows into the temperature stabilization flow path 15, the temperature is adjusted with high accuracy, and the flow is made laminar and directivity (in the −Z direction) perpendicular to the outlet surface of the temperature stabilization flow path 15. Is blown out.

  The temperature-controlled air blown out from the temperature stabilization flow path 15 is temporarily accumulated in the third atmospheric pressure chamber 13 to be uniformed in the Y direction and the X direction. Supplied to the AP. Here, since the shape in the X direction and the shape in the Y direction of the blowing surface 16 are convex in the −Z direction, the temperature-controlled air is blown out so as to spread from the blowing surface 16 toward the measurement light of the laser interferometer. .

  As a result, in the X direction intersecting the optical path LP, the temperature-controlled air at a constant temperature is kept at a constant flow rate without involving air having different temperatures existing in the vicinity of the optical path LP arranged in the air-conditioned space AP into the optical path LP. Can be supplied to the optical path LP. Further, since the temperature-controlled air is blown out in the Y direction along the optical path LP, the temperature-controlled air having a constant temperature can be supplied to the optical path LP at a constant flow rate. As a result, temperature-controlled air having a constant temperature can be supplied at a constant flow rate over the entire optical path LP.

  As mentioned above, although the air conditioner by one Embodiment of this invention was demonstrated, the air conditioner of this invention is not restrict | limited to the said embodiment, It can change freely within the scope of the present invention. For example, in the above-described embodiment, the temperature-controlled air is air-conditioned by making the shape of the blowout surface 16 partitioning the third atmospheric pressure chamber 13 and the air-conditioned space AP convex in the −Z direction with respect to the X direction and the Y direction. Although the air is supplied so as to expand toward the space AP, the shape of the blowout surface 16 is not limited as long as the temperature-controlled air can be supplied to the air-conditioned space AP.

  In the above embodiment, the third atmospheric pressure chamber 13 is provided. However, the configuration corresponding to the blowing surface 16 is provided on the inflow surface side of the temperature stabilizing flow path 15 and the third atmospheric pressure chamber is omitted. Also good. In this case, the outflow surface of the temperature stabilization flow path 15 becomes a boundary with the air-conditioned space AP, but in order to supply the temperature-controlled air so as to spread to the air-conditioned space AP, The shape of the outflow surface may be convex in the −Z direction with respect to the X direction and the Y direction.

  Moreover, in the said embodiment, although it was set as the structure which provided the temperature stabilization flow path 15 between the 2nd atmospheric pressure chamber 12 and the 3rd atmospheric pressure chamber 13, the temperature stabilization flow path 15 is not necessarily an essential structure, A configuration in which a pressure loss sheet similar to the pressure loss sheet 14 is provided instead of the stabilization flow path 15 may be used. Furthermore, in the above-described embodiment, the pressure equalizing member is provided in the communicating portion between the pressure chambers adjacent to each other. For example, the pressure loss sheet 14 is provided between the first atmospheric pressure chamber 11 and the second atmospheric pressure chamber 12, and the temperature stabilization flow path 15 is provided between the second atmospheric pressure chamber 12 and the third atmospheric pressure chamber. However, the pressure equalizing member does not necessarily have to be provided in all the communicating portions of the pressure chambers adjacent to each other, and may be provided in at least one communicating portion.

  Furthermore, although the air conditioner 1 shown in the said embodiment was the structure provided with three atmospheric pressure chambers of the 1st atmospheric pressure chamber 11-the 3rd atmospheric pressure chamber 13, the number of atmospheric pressure chambers should just be two or more, and it is not necessarily 3 atmospheric pressures. It is not limited to rooms. In addition, each of the pressure chambers has a substantially rectangular parallelepiped shape in which nothing is formed inside, but may have a configuration in which a current plate is provided inside.

[Position measuring device and exposure device]
Next, the position measuring apparatus and the exposure apparatus will be described in detail. FIG. 4 is a view showing a schematic configuration of an exposure apparatus according to an embodiment of the present invention provided with a position measuring apparatus according to an embodiment of the present invention. The exposure apparatus shown in FIG. 4 is a so-called step-and-scan type exposure apparatus that sequentially transfers an image of a pattern formed on the reticle R onto the wafer W while moving the reticle R and the wafer W synchronously. In FIG. 4, reference numeral 20 denotes an ultrahigh pressure mercury lamp that emits g-line (wavelength 436 nm), i-line (wavelength 365 nm), KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength 193 nm), or F ₂ excimer laser. The illumination optical system includes a light source (wavelength 157 nm) and the like, and emits illumination light IL shaped into a predetermined shape while making the light intensity distribution of the light emitted from these light sources uniform.

  Reference numeral 21 denotes a reticle stage as a movable body on which a reticle R as a mask is placed. The reticle stage 21 can be finely moved in the direction of the optical axis AX of the projection optical system PL and moved two-dimensionally in a plane perpendicular to the optical axis AX. And is configured to be capable of micro-rotation. A movable mirror 22 as a reflecting portion is attached to one end of the reticle stage 21, and a laser interferometer that forms a part of the position measuring device according to the embodiment of the present invention at a position facing the mirror surface of the movable mirror 22. 24 is arranged. A fixed mirror 23 is attached to the illumination optical system 20 described above. The fixed mirror 23 may be attached to the projection optical system PL.

  The laser interferometer 24 emits two linearly polarized laser beams (light beams) whose polarization directions are orthogonal to each other. One laser beam passes through the polarization beam splitter 25 and is irradiated to the movable mirror 22, and the other laser beam is reflected by the polarization beam splitter 25 and irradiated to the fixed mirror 23 via the mirror 26. The laser light reflected by the movable mirror 22 and the fixed mirror 23 travels in the opposite directions along the incident optical paths LP1 and LP2, and enters the laser interferometer 24. The laser interferometer 24 detects the interference light obtained by causing these laser lights to interfere with each other and obtains position information of the reticle stage 21.

  An air conditioner 27 is disposed above the optical paths LP1 and LP2 (+ Z direction) of the laser light emitted from the laser interferometer 24. This air conditioner 27 is the same as the air conditioner 1 described with reference to FIGS. 1 to 3, and temperature-controlled air having a constant temperature with respect to the optical paths LP1 and LP2 of the laser light emitted from the laser interferometer 24. At a constant flow rate. Since the air conditioner 27 supplies temperature-controlled air in the −Z direction, temperature-controlled air at a constant temperature can be supplied at a constant flow rate to both the optical paths LP1 and LP2 of the laser light. The XYZ orthogonal coordinate system shown in FIG. 4 and the XYZ orthogonal coordinate system shown in FIGS. 1 to 3 are the same coordinate system. For this reason, the air conditioner 27 is arranged with the longitudinal direction set in the Y direction. The air conditioner 27 is fixedly attached to a column (not shown).

  Although the illustration is simplified in FIG. 4, the movable mirror 22 includes a movable mirror having a mirror surface perpendicular to the X axis and a movable mirror having a mirror surface perpendicular to the Y axis. The laser interferometer 24 includes two Y-axis laser interferometers that irradiate the moving mirror 22 with a laser beam along the Y-axis and an X-axis laser that irradiates the movable mirror 22 with a laser beam along the X-axis. The X and Y coordinates of the reticle stage 21 are measured by two laser interferometers for the Y axis and one laser interferometer for the X axis. Further, the rotation angle of the reticle stage 21 is measured by the difference between the measurement values of the two Y-axis laser interferometers. The air conditioner 27 is provided for each laser interferometer.

  Information on the X coordinate, Y coordinate, and rotation angle of the reticle stage 21 detected by the laser interferometer 24 is supplied to the main control system 28. The main control system 28 outputs a control signal to the drive system 29 while monitoring the supplied stage position information, and controls the positioning operation of the reticle stage 21.

  Reticle R placed on reticle stage 21 has a device pattern DP such as a semiconductor element or a liquid crystal display element formed of chromium or the like on the surface of a transparent glass substrate. When the reticle R is illuminated by the illumination light IL emitted from the illumination optical system 20, an image of the device pattern DP formed on the reticle R is transferred onto the wafer W via the projection optical system PL. The wafer W is placed on a wafer stage 30 as a movable body. Note that the surface (pattern surface) on which the device pattern DP of the reticle R is formed and the surface of the wafer W are optically conjugate with respect to the projection optical system PL.

  The wafer stage 30 is an XY stage that moves the wafer W in the XY plane, a Z stage that moves the wafer W in the Z-axis direction, a stage that rotates the wafer W in the XY plane, and an angle with respect to the Z-axis by changing the angle with respect to the Z-axis. The stage is configured to adjust the inclination of the wafer W with respect to the plane. At one end of the upper surface of the wafer stage 30, a moving mirror 31 as a reflecting portion having a length longer than the movable range of the wafer stage 30 is attached, and a laser interferometer 32 is disposed at a position facing the mirror surface of the moving mirror 31. ing. Further, a fixed mirror 33 is attached to the projection optical system PL described above.

  The laser interferometer 32 emits two linearly polarized laser beams whose polarization directions are orthogonal to each other. One laser beam passes through the polarization beam splitter 34 and is irradiated to the movable mirror 31, and the other laser beam is reflected by the polarization beam splitter 34 and irradiated to the fixed mirror 33 via the mirror 35. The laser light reflected by the movable mirror 31 and the fixed mirror 33 travels in the opposite directions along the incident optical paths LP3 and LP4 and enters the laser interferometer 32. The laser interferometer 32 obtains positional information of the wafer stage 30 by detecting the interference light obtained by making these laser lights interfere.

  An air conditioner 36 is arranged above the optical paths LP3 and LP4 (+ Z direction) of the laser light emitted from the laser interferometer 32. The air conditioner 36 is the same as the air conditioner 1 described with reference to FIGS. 1 to 3, and temperature-controlled air having a constant temperature with respect to the optical paths LP 3 and LP 4 of the laser light emitted from the laser interferometer 32. At a constant flow rate. Like the air conditioner 27, the air conditioner 36 supplies temperature-controlled air in the -Z direction, and therefore supplies temperature-controlled air at a constant temperature to both the optical paths LP3 and LP4 of the laser light at a constant flow rate. Can do. The XYZ orthogonal coordinate system shown in FIG. 4 and the XYZ orthogonal coordinate system shown in FIGS. 1 to 3 are the same coordinate system. For this reason, the air conditioner 36 is arranged with the longitudinal direction set in the Y direction. The air conditioner 36 is fixedly attached to a column (not shown).

  Although the illustration is simplified in FIG. 4, the movable mirror 31 includes a movable mirror having a mirror surface perpendicular to the X axis and a movable mirror having a mirror surface perpendicular to the Y axis. FIG. 5 is a perspective view showing the positional relationship between the wafer stage 30, the laser interferometer 32, and the air conditioner 36. As shown in FIG. 5, the movable mirror 31 includes a movable mirror 31X having a mirror surface perpendicular to the X axis and a movable mirror 31Y having a mirror surface perpendicular to the Y axis.

  The laser interferometer 32 includes two Y-axis laser interferometers that irradiate the moving mirror 31 with a laser beam along the Y axis and an X-axis that irradiates the movable mirror 31 with a laser beam along the X axis. The X coordinate and Y coordinate of the wafer stage 30 are measured by one laser interferometer for the Y axis and one laser interferometer for the X axis. In FIG. 5, only one Y-axis laser interferometer 32Y is shown, and the other Y-axis laser interferometer and X-axis laser interferometer are not shown.

  Although only the air conditioner 36 provided in the laser interferometer 32Y is illustrated in FIG. 5, the air conditioner 36 is provided for each laser interferometer. Referring to FIG. 5, the air conditioner 36 is arranged such that the optical path LP4 is positioned at the position of the optical path LP shown in FIGS. A duct 40 is attached to the air inlet 2 of the air conditioner 36, and temperature-controlled air whose temperature is adjusted to be constant is supplied from a blower (not shown). The air conditioner 36 equalizes the flow rate of the temperature-controlled air and performs high-precision temperature adjustment, and supplies temperature-controlled air with a constant flow rate to the optical paths LP3 and LP4.

  Further, the rotation angle of the wafer stage 30 is measured by the difference between the measurement values of the two laser interferometers for the Y axis. Information on the X coordinate, the Y coordinate, and the rotation angle of the wafer stage 30 measured by the laser interferometer 32 is supplied to the main control system 28. The main control system 28 outputs a control signal to the drive system 37 while monitoring the supplied stage position information, and controls the positioning operation of the wafer stage 30.

  Further, the exposure apparatus of the present embodiment includes an off-axis type wafer alignment sensor 38 on the side of the projection optical system PL. The wafer alignment sensor 38 is an FIA (Field Image Alignment) type alignment sensor. The wafer alignment sensor 38 irradiates, for example, a wide-band wavelength light beam emitted from a halogen lamp onto the wafer W as a detection beam, and images the reflected light obtained from the wafer W with an imaging element such as a CCD (Charge Coupled Device). Then, the position information in the X direction and the Y direction of the mark formed on the wafer W is measured by subjecting the obtained image signal to image processing. The measurement result of the wafer alignment sensor 38 is supplied to the main control system 28.

  Further, the exposure apparatus of the present embodiment has an oblique incidence type multi-point main focus sensor (not shown) for measuring the position of the wafer W in the Z-axis direction and the amount of inclination with respect to the XY plane on the side surface of the projection optical system PL. Is installed. This main focus sensor receives an illumination optical system that projects a slit image on a plurality of preset measurement points in an exposure area on which an image of the reticle R is projected on the wafer W, and receives reflected light from these slit images. And a condensing optical system that re-images the slit images and generates a plurality of focus signals corresponding to the lateral shift amounts of the re-imaged slit images. 28. The main control system 28 moves the wafer stage 30 via the drive system 37 so that the surface of the wafer W is always positioned on the best imaging plane of the projection optical system PL based on the focus signal output from the condensing optical system. Control.

  When the image of the device pattern DP formed on the reticle R is transferred onto the wafer W, first, the main control system 28 measures the accurate position information of the reticle R using a reticle alignment system (not shown) and also performs wafer alignment. After measuring the accurate position information of the wafer W using the system, the relative positions of the reticle R and the wafer W are adjusted based on these measurement results and the measurement results of the laser interferometer 24 and the laser interferometer 32. . Next, a control signal is output to the drive system 29 and the drive system 37 to start movement of the reticle R and the wafer W, and the reticle R is irradiated with slit-shaped illumination light IL. Thereafter, while the detection results of the laser interferometer 24 and the laser interferometer 32 are monitored, the reticle R and the wafer W are moved synchronously to sequentially transfer the device pattern DP onto the wafer W.

  As mentioned above, although one Embodiment of this invention was described, this invention is not necessarily limited to the said embodiment, It can change freely within the scope of the present invention. For example, in the above-described embodiment, the position measuring device that measures the position in the two-dimensional plane of the stages 21 and 30 provided in the exposure apparatus has been described as an example. However, the position measuring device of the present invention is not limited to this. For example, as disclosed in, for example, Japanese Patent Application Laid-Open No. 10-97982, Japanese Patent Application Laid-Open No. 2000-49066, and Special Table 2001-513267, a measurement object such as a stage that moves in a two-dimensional plane. The present invention can be applied to a position measuring apparatus that measures position information, rotation, inclination, and the like in a direction orthogonal to the two-dimensional plane.

In the above embodiment, the step-and-scan type exposure apparatus has been described as an example. However, the present invention can also be applied to a step-and-repeat type exposure apparatus. The light source provided in the illumination optical system 20 of the exposure apparatus of this embodiment is not limited to an ultrahigh pressure mercury lamp, KrF excimer laser, ArF excimer laser, or F ₂ laser, but also charged particle beams such as X-rays and electron beams. Can be used. For example, when an electron beam is used, thermionic emission type lanthanum hexabolite (LaB ₆ ) or tantalum (Ta) can be used as the electron gun. In the above-described embodiment, the case of manufacturing a semiconductor element or a liquid crystal display element has been described as an example. Of course, the exposure apparatus is used for manufacturing a thin film magnetic head and transfers a device pattern onto a ceramic wafer. The present invention can also be applied to an exposure apparatus used for manufacturing an image sensor such as a CCD.

  Furthermore, a single wavelength laser beam in the infrared region or visible region oscillated from a DFB semiconductor laser or fiber laser as a light source is amplified by, for example, a fiber amplifier doped with erbium (or both erbium and yttrium), and nonlinear optics You may use the harmonic which wavelength-converted into the ultraviolet light using the crystal | crystallization. For example, if the oscillation wavelength of a single wavelength laser is in the range of 1.51 to 1.59 μm, the generated wavelength is in the range of 189 to 199 nm, the eighth harmonic, or the generated wavelength is in the range of 151 to 159 nm. A 10th harmonic is output.

In particular, when the oscillation wavelength is in the range of 1.544 to 1.553 μm, an 8th harmonic in the range of 193 to 194 nm, that is, ultraviolet light having substantially the same wavelength as the ArF excimer laser light is obtained. When the oscillation wavelength is in the range of 1.57 to 1.58 μm, the 10th harmonic wave in the range of 157 to 158 nm, that is, ultraviolet light having substantially the same wavelength as the F ₂ laser light is obtained. Further, if the oscillation wavelength is in the range of 1.03 to 1.12 μm, the seventh harmonic whose output wavelength is in the range of 147 to 160 nm is output, and in particular, the oscillation wavelength is in the range of 1.099 to 1.106 μm. If it is inside, the 7th harmonic in the range of 157 to 158 μm, that is, ultraviolet light having substantially the same wavelength as the F ₂ laser light is obtained. In this case, for example, an yttrium-doped fiber laser can be used as the single wavelength oscillation laser.

  Further, the present invention is not limited to an exposure apparatus used for manufacturing a semiconductor element, but also used for manufacturing a display including a liquid crystal display element (LCD) and the like, an exposure apparatus for transferring a device pattern onto a glass plate, and a thin film magnetic head. The present invention can also be applied to an exposure apparatus that is used for manufacturing and transfers a device pattern onto a ceramic wafer, and an exposure apparatus that is used to manufacture an image sensor such as a CCD. Furthermore, in an exposure apparatus that transfers a circuit pattern onto a glass substrate or a silicon wafer in order to manufacture a reticle or mask used in an optical exposure apparatus, EUV exposure apparatus, X-ray exposure apparatus, electron beam exposure apparatus, or the like. The present invention can also be applied. Here, in an exposure apparatus using DUV (far ultraviolet) light, VUV (vacuum ultraviolet) light, or the like, a transmission type reticle is generally used. As a reticle substrate, quartz glass, fluorine-doped quartz glass, fluorite, Magnesium fluoride or quartz is used. Further, in a proximity type X-ray exposure apparatus or an electron beam exposure apparatus, a transmission mask (stencil mask, membrane mask) is used, and a silicon wafer or the like is used as a mask substrate.

  Next, an embodiment of a microdevice manufacturing method using the above-described exposure apparatus in a lithography process will be described. FIG. 6 is a flowchart showing a manufacturing example of a micro device (a semiconductor chip such as an IC or LSI, a liquid crystal panel, a CCD, a thin film magnetic head, a micro machine, or the like). As shown in FIG. 6, first, in step S10 (design step), a function / performance design (for example, circuit design of a semiconductor device) of a micro device is performed, and a pattern design for realizing the function is performed. Subsequently, in step S11 (mask manufacturing step), a mask (reticle) on which the designed circuit pattern is formed is manufactured. On the other hand, in step S12 (wafer manufacturing step), a wafer is manufactured using a material such as silicon.

  Next, in step S13 (wafer processing step), as will be described later, an actual circuit or the like is formed on the wafer using lithography and the like using the mask and wafer prepared in steps S10 to S12. Next, in step S14 (device assembly step), device assembly is performed using the wafer processed in step S13. This step S14 includes processes such as a dicing process, a bonding process, and a packaging process (chip encapsulation) as necessary. Finally, in step S15 (inspection step), inspections such as an operation confirmation test and a durability test of the microdevice manufactured in step S14 are performed. After these steps, the microdevice is completed and shipped.

  FIG. 7 is a diagram showing an example of a detailed flow of step S13 in FIG. 6 in the case of a semiconductor device. In FIG. 7, in step S21 (oxidation step), the surface of the wafer is oxidized. In step S22 (CVD step), an insulating film is formed on the wafer surface. In step S23 (electrode formation step), an electrode is formed on the wafer by vapor deposition. In step S24 (ion implantation step), ions are implanted into the wafer. Each of the above steps S21 to S24 constitutes a pretreatment process at each stage of the wafer processing, and is selected and executed according to a necessary process at each stage.

  At each stage of the wafer process, when the above-described pre-processing step is completed, the post-processing step is executed as follows. In this post-processing step, first, in step S25 (resist formation step), a photosensitive agent is applied to the wafer. In step S26 (exposure step), the circuit pattern of the mask is transferred to the wafer by the lithography system (exposure apparatus) and the exposure method described above. Next, in step S27 (development step), the exposed wafer is developed, and in step S28 (etching step), the exposed members other than the portion where the resist remains are removed by etching. In step S29 (resist removal step), the resist that has become unnecessary after the etching is removed. By repeatedly performing these pre-processing steps and post-processing steps, multiple circuit patterns are formed on the wafer.

  In the microdevice manufacturing method described above, since the positional information of the mask and the wafer is measured with high accuracy using the signal processing method described above in the exposure step (step S26), the pattern already formed on the wafer Overlay accuracy with a pattern transferred onto a wafer can be improved, and as a result, a highly integrated device having a minimum line width of about 0.1 μm can be produced with a high yield.

  Further, in order to manufacture reticles or masks used in not only microdevices such as semiconductor elements but also light exposure apparatuses, EUV exposure apparatuses, X-ray exposure apparatuses, electron beam exposure apparatuses, etc., from mother reticles to glass substrates and The present invention can also be applied to an exposure apparatus that transfers a circuit pattern to a silicon wafer or the like. Here, in an exposure apparatus using DUV (deep ultraviolet), VUV (vacuum ultraviolet) light, or the like, a transmission type reticle is generally used. As a reticle substrate, quartz glass, fluorine-doped quartz glass, fluorite, Magnesium fluoride or quartz is used. In proximity type X-ray exposure apparatuses, electron beam exposure apparatuses, and the like, a transmissive mask (stencil mask, membrane mask) is used, and a silicon wafer or the like is used as a mask substrate. Such an exposure apparatus is disclosed in WO99 / 34255, WO99 / 50712, WO99 / 66370, JP-A-11-194479, JP-A2000-12453, JP-A-2000-29202, and the like. .

It is an upper surface perspective view which shows the structure of the air conditioner by one Embodiment of this invention. It is a cross-sectional arrow view along the AA line in FIG. It is a cross-sectional arrow view along the BB line in FIG. It is a figure which shows schematic structure of the exposure apparatus by one Embodiment of this invention provided with the position measuring device by one Embodiment of this invention. 3 is a perspective view showing a positional relationship among a wafer stage 30, a laser interferometer 32, and an air conditioner 36. FIG. It is a flowchart which shows an example of the manufacturing process of a microdevice. It is a figure which shows an example of the detailed flow of step S13 of FIG. 6 in the case of a semiconductor device.

Explanation of symbols

1 Air conditioner 2 Air inlet (inlet)
11 First atmospheric pressure chamber 12 Second atmospheric pressure chamber 13 Third atmospheric pressure chamber 14 Pressure loss sheet (pressure equalizing member)
15 Temperature stabilization flow path (pressure equalization member, temperature control member)
16 Outlet surface (air guide member)
17 Support member (decompression wall)
21 Reticle stage (movable body, mask stage)
22 Moving mirror (reflection part)
24 Laser interferometer (interferometer)
27 Air conditioner 30 Wafer stage (movable body, substrate stage)
31 Moving mirror (reflection part)
32 Laser interferometer (interferometer)
36 Air conditioner AP Air-conditioned space R Reticle (mask)
W wafer (substrate)

Claims (15)

In an air conditioner that supplies gas adjusted to a predetermined temperature to an air-conditioned space,
The gas inlet;
An air guide member for supplying the gas to the air-conditioned space;
An air conditioner comprising: a plurality of pressure chambers provided between the inlet and the air guide member and communicating with each other.   2. The air conditioner according to claim 1, wherein at least one of the communicating portions of the pressure chambers adjacent to each other includes a pressure equalizing member that equalizes a pressure distribution of the gas in each of the pressure chambers.   The air conditioner according to claim 2, wherein at least one of the pressure equalizing members is a temperature control member that controls a temperature of the gas passing therethrough to a predetermined temperature.   4. The air conditioner according to claim 1, wherein the air guide member supplies the gas so as to expand toward the air-conditioned space. 5. The atmospheric pressure chamber is a first atmospheric pressure chamber that distributes the gas flowing in from the inlet along a first direction;
A second pressure chamber that distributes the gas that has passed through the first pressure chamber in a second direction that intersects the first direction;
A third pressure chamber located between the second pressure chamber and the air guide member and located in a third direction intersecting both the first direction and the second direction with respect to the second pressure chamber; The air conditioner according to any one of claims 1 to 4, further comprising:   6. The air conditioner according to claim 5, wherein a length of the first atmospheric pressure chamber in the first direction is longer than a length of the second atmospheric pressure chamber in the second direction.   The supply direction of the gas to the air-conditioned space is the third direction, and the air guide member supplies the gas so as to spread along at least one of the first direction and the second direction. The air conditioner according to claim 5 or 6, characterized in that.   The air conditioning apparatus according to claim 7, wherein the air guide member is a mesh member having a curvature in a plane including the second direction and the third direction.   The air conditioner according to any one of claims 5 to 8, wherein the first atmospheric pressure chamber includes a decompression wall with which the gas flowing in from the inflow port collides. In a position measurement apparatus comprising: a movable body that can move in a predetermined direction; and an interferometer that measures the position of the movable body by irradiating a light beam to a reflecting portion provided on the movable body.
An air conditioner having an air guide member that blows a gas adjusted to a predetermined temperature toward the light beam, and supplies the gas so that the gas sent from the air guide member spreads toward the light beam. A position measuring device comprising the device.   The said air conditioner is equipped with the air conditioner which supplies the said gas so that the said gas sent out from the said air guide member may spread in the direction which cross | intersects the optical axis direction of the said light beam, It is characterized by the above-mentioned. Position measuring device. The air conditioner includes the gas inlet, a wind guide member that supplies the gas, and a plurality of pressure chambers that are provided between the inlet and the wind guide member and communicate with each other.
The at least one of the communicating parts of the pressure chambers adjacent to each other includes a pressure equalizing member that equalizes the pressure distribution of the gas in each of the pressure chambers. Position measuring device.   The position measuring device according to claim 12, wherein at least one of the pressure equalizing members is a temperature control member that controls a temperature of the passing gas to a predetermined temperature. The air conditioner has a first atmospheric pressure chamber that distributes the gas flowing in from the inlet along a first direction, and a second gas that intersects the first direction with the gas that has passed through the first atmospheric pressure chamber. A second atmospheric pressure chamber to be distributed, and a third direction between the second atmospheric pressure chamber and the wind guide member and intersecting both the first direction and the second direction with respect to the second atmospheric pressure chamber. A third atmospheric pressure chamber located at
The position measuring apparatus according to claim 12, wherein the first direction is parallel to an optical axis direction of the light beam. In an exposure apparatus that includes a mask stage that holds a mask and a substrate stage that holds a substrate, and transfers a pattern formed on the mask onto the substrate.
15. An exposure apparatus comprising the position measuring device according to claim 10, wherein position information of at least one of the mask stage and the substrate stage is measured as position information of the movable body. .

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