Substrate-processing device

Abstract

A distance measurement instrument (26) is disposed apart from a stage (21) on one side in the scanning direction of the stage (21). The distance measurement instrument (26) emits laser light toward a lateral surface (211) perpendicular to the scanning direction of the stage (21) and receives reflected light from the lateral surface (211) to thereby measure the distance to the stage (21) in the scanning direction. A first gas supply unit (71) discharges gas toward the stage (21) along the scanning direction from an annular discharge port (711) disposed apart from the stage (21) on said one side in the scanning direction of the stage (21) to thereby form a cylindrical airflow that surrounds the laser light and flows toward the stage (21) along the scanning direction. Accordingly, it is possible to suppress temperature fluctuations on the optical path of the laser light emitted from the distance measurement instrument (26).

Description

Substrate Processing Equipment

[0001] The present invention relates to a substrate processing apparatus for processing a substrate. [Reference to Related Applications] This application claims the benefit of priority from Japanese Patent Application JP2024-145655, filed on August 27, 2024, the entire disclosure of which is incorporated herein by reference.

[0002] Conventionally, when drawing a pattern on a printed circuit board, a semiconductor board, or the like (hereinafter referred to as a "board"), a drawing device has been used that irradiates a photosensitive material formed on the board with modulated light and scans the irradiated area of ​​the light to directly draw the pattern.

[0003] In such a drawing apparatus, the position of the stage holding the substrate is measured by a laser interferometer, and the substrate is positioned based on the measurement results. Laser interferometers produce measurement errors due to variations in the refractive index of air along the laser optical path. Such refractive index variations are primarily caused by temperature fluctuations along the laser optical path.

[0004] Therefore, Japanese Patent Laid-Open No. 2002-359185 (Document 1) proposes a technology for suppressing temperature fluctuations along the optical path and reducing measurement errors of the laser interferometer by providing an air blowing device that blows air along the optical path of the laser interferometer toward the stage in an exposure apparatus that projects a pattern from an original onto a substrate. Also, Japanese Patent Laid-Open No. 9-243324 (Document 2) proposes a technology for blowing air controlled to a constant temperature from an oblique side of the XY stage in a laser interferometer-type XY positioning device.

[0005] In recent years, as patterns drawn on substrates have become increasingly finer, there has been a demand for improved substrate positioning accuracy, which has led to a need to further suppress temperature fluctuations along the optical path of laser light emitted from distance measuring devices such as laser interferometers.

[0006] The present invention has been made in view of the above-mentioned problems, and has as its object to suppress temperature fluctuations on the optical path of laser light emitted from a distance measuring device.

[0007] A first aspect of the present invention is a substrate processing apparatus comprising: a stage for holding a substrate; a processing section for performing a predetermined process on the substrate; a stage moving mechanism for moving the stage relative to the processing section in a scanning direction parallel to an upper surface of the substrate; a distance measuring device arranged on one side of the stage in the scanning direction and spaced apart from the stage, for measuring a distance between the stage in the scanning direction by emitting laser light toward a surface to be measured that is perpendicular to the scanning direction of the stage and receiving reflected light from the surface to be measured; and a first gas supply unit arranged on one side of the stage in the scanning direction and spaced apart from the stage, for injecting gas toward the stage along the scanning direction from a circular injection port arranged on the one side of the stage in the scanning direction and spaced apart from the stage, thereby forming a cylindrical airflow that surrounds the laser light and flows toward the stage along the scanning direction.

[0008] According to the present invention, it is possible to suppress temperature fluctuations on the optical path of the laser light emitted from the distance measuring device.

[0009] A second aspect of the present invention is the substrate processing apparatus of the first aspect, wherein the gas is ejected from the circumferential ejection port in a direction parallel to the laser light.

[0010] Aspect 3 of the present invention is a substrate processing apparatus according to aspect 1 (which may be aspect 1 or 2), wherein the flow velocity of the cylindrical airflow in the scanning direction is greater than the moving speed of the stage in the scanning direction by the stage moving mechanism.

[0011] A fourth aspect of the present invention is the substrate processing apparatus of Aspect 1 (which may be any one of Aspects 1 to 3), further comprising a second gas supply unit that sprays gas toward the stage along the scanning direction from side injection ports that are arranged on one side of the stage in the scanning direction and that are arranged around the circumferential injection port in a side view parallel to the scanning direction, thereby forming a lateral airflow that flows toward the stage along the scanning direction around the tubular airflow.

[0012] A fifth aspect of the present invention is the substrate processing apparatus of the fourth aspect, wherein the gas jet flow velocity from the peripheral jet nozzle is the same as the gas jet flow velocity from the side jet nozzle.

[0013] A sixth aspect of the present invention is the substrate processing apparatus of the fourth aspect (which may be the fourth or fifth aspect), wherein the gas ejected from the peripheral injection port has the same temperature as the gas ejected from the side injection port.

[0014] A seventh aspect of the present invention is the substrate processing apparatus of Aspect 4 (which may be any one of Aspects 4 to 6), further comprising a support part that is gate-shaped in a side view and supports the processing part above the stage and that is erected across the stage, wherein the entire side injection nozzle is located inside the gate-shaped support part in a side view.

[0015] Aspect 8 of the present invention is the substrate processing apparatus of Aspect 1 (which may be any one of Aspects 1 to 7), further comprising: another distance measuring device disposed on the one side of the stage in the scanning direction at a distance from the stage, and configured to measure the distance to the stage in the scanning direction by emitting laser light toward the measurement surface of the stage and receiving reflected light from the measurement surface. The first gas supply unit injects gas toward the stage along the scanning direction from another circular jet nozzle disposed on the one side of the scanning direction at a distance from the stage and disposed on one side of the direction perpendicular to the scanning direction from the circular jet nozzle, thereby forming another cylindrical airflow that surrounds the periphery of the laser light from the other distance measuring device and flows toward the stage along the scanning direction.

[0016] A ninth aspect of the present invention is the substrate processing apparatus of Aspect 1 (which may be any one of Aspects 1 to 8), further comprising a third gas supply unit that injects gas downward from an upper injection port disposed above the stage, wherein injection of gas from the circular injection port and injection of gas from the upper injection port are selectively performed.

[0017] A tenth aspect of the present invention is the substrate processing apparatus according to any one of the first to ninth aspects, wherein the processing section is a drawing section that draws a pattern by irradiating the substrate with light.

[0018] The above and other objects, features, aspects and advantages will become more apparent from the following detailed description of the invention which proceeds with reference to the accompanying drawings.

[0019] It is a perspective view showing a drawing apparatus according to an embodiment. It is a front view showing the drawing apparatus. It is a side view showing a first gas supply unit and a second gas supply unit. It is a graph showing the measurement accuracy of a distance measuring device. It is a graph showing the measurement accuracy of a distance measuring device in a gas supply state of a comparative example.

[0020] FIG. 1 is a perspective view showing a drawing apparatus 1 according to one embodiment of the present invention. The drawing apparatus 1 is one type of substrate processing apparatus that performs a predetermined process on a substrate 9. Specifically, the drawing apparatus 1 is a direct drawing apparatus that draws a pattern by irradiating a photosensitive material on the substrate 9 with spatially modulated, approximately beam-like light and scanning the light irradiation area on the substrate 9. In FIG. 1, three mutually orthogonal directions are indicated by arrows as the X direction, the Y direction, and the Z direction. In the example shown in FIG. 1, the X direction and the Y direction are horizontal directions that are perpendicular to each other, and the Z direction is a vertical direction (i.e., an up-down direction). The same applies to other figures.

[0021] The substrate 9 is, for example, a printed circuit board having a substantially rectangular flat plate shape. On the (+Z) side main surface (hereinafter also referred to as the "top surface 91") of the substrate 9, a resist film formed of a photosensitive material is provided on a copper layer. In the drawing device 1, a circuit pattern is drawn (i.e., formed) on the resist film of the substrate 9. Note that the type and shape of the substrate 9 may be variously changed.

[0022] Fig. 2 is a front view of the imaging apparatus 1 as viewed from the (+X) side. As shown in Figs. 1 and 2, the imaging apparatus 1 includes a stage 21, a stage movement mechanism 22, an alignment unit 3, an imaging unit 4, a base 51, and a housing 52. To facilitate understanding of the drawing, Fig. 1 omits the illustration of the housing 52 and shows the components housed inside the housing 52. Fig. 2 also shows the housing 52 in cross section.

[0023] The housing 52 is a casing that houses the stage 21, the stage moving mechanism 22, the alignment unit 3, the imaging unit 4, the base 51, etc. in its internal space. The internal space of the housing 52 is isolated from the space outside the housing 52. In the example shown in Fig. 2, the housing 52 has a substantially rectangular parallelepiped shape in which the length in the Y direction is longer than the length in the X direction.

[0024] The stage 21 is a substantially rectangular, flat member that is located below the alignment unit 3 and the imaging unit 4 (i.e., on the (-Z) side). The stage 21 includes a substrate holding unit 25 that holds the horizontal substrate 9 from below. The substrate holding unit 25 is, for example, a vacuum chuck that holds the lower surface of the substrate 9 by suction. The substrate holding unit 25 may have a structure other than a vacuum chuck, and may be, for example, a mechanical chuck. The upper surface 91 of the substrate 9 placed on the substrate holding unit 25 is substantially perpendicular to the Z direction and substantially parallel to the X and Y directions.

[0025] The stage moving mechanism 22 is a moving mechanism that moves the stage 21 relatively in the horizontal direction (i.e., in a direction approximately parallel to the upper surface 91 of the substrate 9) with respect to the alignment unit 3 and the imaging unit 4. The stage moving mechanism 22 is attached to the upper surface of the base 51 and is supported from below by the base 51. The base 51 has, for example, an approximately rectangular parallelepiped shape with a length in the Y direction longer than its length in the X direction.

[0026] The stage moving mechanism 22 includes a first moving mechanism 23 and a second moving mechanism 24. The second moving mechanism 24 supports the stage 21 from below and moves the stage 21 linearly in the X direction along a guide rail. The first moving mechanism 23 supports the second moving mechanism 24 from below and moves the stage 21 linearly in the Y direction along the guide rail together with the second moving mechanism 24. When the imaging apparatus 1 is in an idle state, the stage 21 is disposed at a standby position near the end of the stage moving mechanism 22 on the (-Y) side.

[0027] The drive sources of the first moving mechanism 23 and the second moving mechanism 24 are, for example, linear servo motors or motors attached to ball screws. The motors or the like that serve as the drive sources of the first moving mechanism 23 and the second moving mechanism 24 move together with the stage 21. The structures of the first moving mechanism 23 and the second moving mechanism 24 may be modified in various ways.

[0028] The drawing apparatus 1 may be provided with a stage rotation mechanism that rotates the stage 21 around a rotation axis extending in the Z direction. The drawing apparatus 1 may also be provided with a stage lifting mechanism that moves the stage 21 in the Z direction. For example, a servo motor can be used as the stage rotation mechanism. For example, a linear servo motor can be used as the stage lifting mechanism. The structures of the stage rotation mechanism and the stage lifting mechanism may be modified in various ways.

[0029] The alignment unit 3 includes a plurality of alignment cameras 31 (two in the example shown in FIG. 1 ) arranged in the X direction. Each alignment camera 31 is supported above the stage 21 and the stage movement mechanism 22 by a support unit 40 that straddles the stage 21 and the stage movement mechanism 22. The support unit 40 is, for example, a single member that is provided at one position in the Y direction. In the example shown in FIGS. 1 and 2 , the support unit 40 is a gate-shaped member (a so-called gantry) when viewed parallel to the Y direction (i.e., when viewed from the side), and is erected on the upper surface of the base 51. The gate shape is a shape in which the (+Z) side ends of two pillars extending in the Z direction are connected by a beam extending in a substantially horizontal direction.

[0030] 1 and 2, the two alignment cameras 31 are attached to the (+Y) side surface of the support unit 40. Of the two alignment cameras 31, for example, one alignment camera 31 is fixed to the support unit 40, and the other alignment camera 31 is movable in the X direction on the support unit 40. This makes it possible to change the distance in the X direction between the two alignment cameras 31. Note that the number of alignment cameras 31 in the alignment unit 3 may be one, or may be three or more.

[0031] Each alignment camera 31 captures an image of an alignment mark (not shown) that is provided in advance on the upper surface 91 of the substrate 9. In the drawing device 1, alignment of the substrate 9 (i.e., correction of the relative position of the substrate 9 with respect to the drawing head 41) is performed based on the image of the alignment mark acquired by the alignment camera 31.

[0032] The imaging unit 4 includes a plurality of imaging heads 41 (six in the example shown in FIG. 1 ) arranged in the X direction. The plurality of imaging heads 41 have substantially the same structure. Each imaging head 41 includes a spatial light modulator that irradiates modulated (i.e., spatially modulated) light downward. Each imaging head 41 is supported above the stage 21 and the stage movement mechanism 22 by the support unit 40 described above. In the example shown in FIGS. 1 and 2 , the six imaging heads 41 are attached to the (−Y) side surface of the support unit 40. In other words, the six imaging heads 41 are arranged on the opposite side of the support unit 40 from the two alignment cameras 31 described above in the Y direction.

[0033] 1 and 2, the six drawing heads 41 are arranged in a substantially straight line substantially parallel to the X direction. The six drawing heads 41 are positioned substantially the same in the Y and Z directions. Note that the multiple drawing heads 41 do not necessarily have to be arranged in a straight line, and may be arranged in a staggered pattern, for example. Furthermore, the number of drawing heads 41 in the drawing unit 4 may be one, or two or more.

[0034] In the drawing apparatus 1, pattern drawing on the substrate 9 is performed by a so-called multi-pass method. Specifically, while modulated light from the multiple drawing heads 41 of the drawing unit 4 is irradiated onto the upper surface 91 of the substrate 9, the first moving mechanism 23 of the stage moving mechanism 22 moves the substrate 9 in the Y direction to pass below the drawing heads 41. As a result, the areas irradiated with light from the multiple drawing heads 41 are scanned in the Y direction on the substrate 9, and drawing on the substrate 9 is performed. Subsequently, the second moving mechanism 24 moves the substrate 9 stepwise a predetermined distance in the X direction. Then, the first moving mechanism 23 moves the substrate 9 in the Y direction, and light is again irradiated from the drawing heads 41 onto the substrate 9 in parallel with this movement, thereby performing drawing on the substrate 9.

[0035] In the drawing device 1, a pattern is drawn on the substrate 9 by alternately irradiating the substrate 9 with light as it moves in the Y direction and stepping the substrate 9 in the X direction. The drawing unit 4 is a processing unit that performs a predetermined process (i.e., drawing process) on the substrate 9.

[0036] In the following description, the Y direction will also be referred to as the "main scanning direction" or "scanning direction," and the (+Y) side and the (-Y) side will also be referred to as the "front side" and the "rear side," respectively. The X direction will also be referred to as the "sub-scanning direction" or "width direction." The main scanning direction and the sub-scanning direction are directions that are approximately parallel to the upper surface 91 of the substrate 9. In the stage movement mechanism 22, the first movement mechanism 23 is a main scanning mechanism that moves the stage 21 relative to the drawing head 41 in the main scanning direction. The second movement mechanism 24 is a sub-scanning mechanism that moves the stage 21 relative to the drawing head 41 in the sub-scanning direction.

[0037] In the drawing apparatus 1, drawing on the substrate 9 may be performed by a single-pass method (also called a one-pass method), in which drawing of a pattern on the substrate 9 is completed by moving the substrate 9 relative to the drawing head 41 only once in the Y direction. In this case, sub-scanning of the substrate 9 by the second moving mechanism 24 (i.e., step movement in the X direction) is not performed when drawing the pattern. In other words, the stage moving mechanism 22 is a scanning mechanism that moves the stage 21 relative to the drawing head 41 at least in the scanning direction.

[0038] 2, the imaging apparatus 1 further includes two distance measuring devices 26 that are arranged on the (+Y) side of the stage 21 at a distance from the stage 21 on the (+Y) side. The two distance measuring devices 26 are arranged side by side in the X direction on a support base 261 that is provided on the upper surface of the base 51. The support base 261 is located near the end of the (+Y) side of the stage moving mechanism 22 (i.e., near the end of the stage 21 on the opposite side from the standby position). The positions of the two distance measuring devices 26 in the Y direction are approximately the same. The two distance measuring devices 26 are located at approximately the same position as the side surface 211 on the (+Y) side of the stage 21 in the Z direction.

[0039] Each distance measuring device 26 emits laser light toward a side surface 211 on the (+Y) side of the stage 21 and receives reflected light from the side surface 211 to measure the distance between itself and the stage 21 in the Y direction (i.e., the scanning direction). In FIGS. 1 and 2 , the optical axis J1 of the laser light emitted from the distance measuring device 26 is indicated by a dashed dotted line. The optical axis J1 is a straight line that is approximately parallel to the Y direction. The distance measuring device 26 is, for example, a laser interferometer. The distance measuring device 26 may be a single-pass laser interferometer or a double-pass laser interferometer.

[0040] In the imaging device 1, the position of the stage 21 in the Y direction and the orientation of the stage 21 in the circumferential direction (i.e., the rotation direction) around the rotation axis are obtained based on the outputs from the two distance measuring devices 26. The side surface 211 on the (+Y) side of the stage 21 is a surface perpendicular to the Y direction and is, for example, a mirror surface that favorably reflects laser light. The side surface 211 on the (+Y) side of the stage 21 is a measurement surface whose distance is measured by the distance measuring devices 26.

[0041] The drawing apparatus 1 further includes a first gas supply unit 71, a second gas supply unit 72, and a third gas supply unit 73. The first gas supply unit 71 and the second gas supply unit 72 are arranged on the (+Y) side (i.e., front side) of the stage 21, spaced apart from the stage 21 on the (+Y) side. The first gas supply unit 71 is arranged on the (-Y) side of the distance measurement device 26 (i.e., between the distance measurement device 26 and the stage 21). The first gas supply unit 71 is arranged, for example, on the support table 261 described above. The second gas supply unit 72 is arranged, for example, on the (+Y) side of the first gas supply unit 71 and the distance measurement device 26, spaced apart above the upper surface of the base 51. The third gas supply unit 73 is arranged on the canopy of the housing 52, above the stage 21 and the stage moving mechanism 22.

[0042] The first gas supply unit 71, the second gas supply unit 72, and the third gas supply unit 73 are connected to a gas supply source 79 provided outside the drawing apparatus 1 via a pipe 78. Note that the gas supply source 79 and the like are not shown in FIG. 1 . A switching unit 77 is provided on the pipe 78. The switching unit 77 switches the supply destination of the gas (e.g., compressed air) supplied from the gas supply source 79 between the first gas supply unit 71, the second gas supply unit 72, and the third gas supply unit 73. A temperature adjustment unit 76 is provided on the pipe 78 between the switching unit 77 and the gas supply source 79. The temperature adjustment unit 76 adjusts the temperatures of the gases supplied to the first gas supply unit 71, the second gas supply unit 72, and the third gas supply unit 73 to desired temperatures.

[0043] The third gas supply unit 73 is, for example, a fan filter unit (FFU). The third gas supply unit 73 includes an upper injection port 731. The upper injection port 731 is disposed above the stage 21 and the stage moving mechanism 22, and injects gas downward (i.e., in the (-Z) direction). This forms a downflow that flows in the (-Z) direction inside the housing 52.

[0044] 3 is an enlarged side view of the first gas supply unit 71 and the second gas supply unit 72 viewed from the (-Y) side. In FIG. 3, the support unit 40 described above is also indicated by a two-dot chain line. The first gas supply unit 71 includes two cylindrical portions 712 arranged on a support base 261. The two cylindrical portions 712 are arranged adjacent to the (-Y) sides of the two distance measuring devices 26. The two cylindrical portions 712 are arranged spaced apart in the X direction.

[0045] The (+X) side tube portion 712 is a substantially cylindrical member extending substantially parallel to the Y direction with the optical axis J1 of the (+X) side distance measuring device 26 as its approximate center. The laser light emitted from the (+X) side distance measuring device 26 passes through the inside of the (+X) side tube portion 712. The (-Y) side end of the (+X) side distance measuring device 26 is in contact with the (+Y) side end of the (+X) side tube portion 712, for example. The (-X) side tube portion 712 is a substantially cylindrical member extending substantially parallel to the Y direction with the optical axis J1 of the (-X) side distance measuring device 26 as its approximate center. The laser light emitted from the (-X) side distance measuring device 26 passes through the inside of the (-X) side tube portion 712. The (-Y) side end of the (-X) side distance measuring device 26 is in contact with the (+Y) side end of the (-X) side tube portion 712, for example.

[0046] A circumferential injection port 711 having a substantially circular shape and centered substantially on the optical axis J1 of the distance measuring device 26 is provided at the end on the (-Y) side of each cylindrical portion 712. The circumferential injection port 711 is a slit-shaped opening that is substantially perpendicular to the Y direction. The two circumferential injection ports 711 are located at substantially the same position in the Y direction and are spaced apart in the X direction.

[0047] Gas supplied from the gas supply source 79 to the first gas supply unit 71 is injected from the two circumferential injection ports 711 toward the stage 21 in the Y direction (i.e., the scanning direction). This forms a substantially cylindrical airflow that completely surrounds the laser light emitted from the distance measuring device 26 and the light reflected from the side surface 211 on the (+Y) side of the stage 21. The circumferential airflow flows from the circumferential injection ports 711 toward the stage 21 in the Y direction.

[0048] In this embodiment, gas is injected from the circular injection port 711 in the (-Y) direction (i.e., parallel to the scanning direction), and the cylindrical airflow extends approximately parallel to the Y direction. In other words, the direction in which gas is injected from the circular injection port 711 is approximately parallel to the laser light emitted from the distance measuring device 26. The cylindrical airflow also extends approximately parallel to the laser light. The flow velocity of the cylindrical airflow in the Y direction is greater than the movement speed of the stage 21 in the Y direction by the stage moving mechanism 22. Preferably, regardless of the position of the stage 21 in the Y direction, the flow velocity of the cylindrical airflow in the Y direction is greater than the movement speed of the stage 21 in the Y direction by the stage moving mechanism 22 at approximately the same position as the side surface 211 of the stage 21 in the Y direction.

[0049] The diameter of the circular injection port 711 is, for example, 10 mm to 50 mm, and is 25 mm in this embodiment. When the distance measuring device 26 is a double-path laser interferometer that emits two laser beams, the diameter of the circular injection port 711 is preferably about 1.4 to 1.7 times the distance between the two laser beams (i.e., the distance in the direction perpendicular to the laser beams).

[0050] The second gas supply unit 72 is disposed around the first gas supply unit 71 in a side view. In the example shown in FIG. 3 , the second gas supply units 72 are disposed on the (+Z) side, the (+X) side, and the (−X) side of the two cylindrical portions 712 of the first gas supply unit 71 in a side view. The second gas supply unit 72 has an outer shape, for example, resembling a combination of rectangular parallelepipeds. A planar side injection port 721 extending approximately perpendicularly in the Y direction is provided at the (−Y) side end of the second gas supply unit 72. In the example shown in FIG. 3 , the side injection port 721 is divided into two parts approximately at the center in the X direction, and the (+X) side portion and the (−X) side portion are each approximately L-shaped.

[0051] The side jet ports 721 are arranged around the two circumferential jet ports 711 in a side view, and do not overlap with the two circumferential jet ports 711 in a side view. Specifically, the side jet ports 721 are located on the (+Z) side, (+X) side, and (-X) side of the two circumferential jet ports 711. In a side view, the area of ​​the side jet ports 721 is significantly larger than the area of ​​each of the circumferential jet ports 711.

[0052] 3 , the entire side jet port 721 and the entire two circular jet ports 711 are located inside the gate-shaped support portion 40 in a side view. In other words, in a side view, the support portion 40 does not overlap even partially with the side jet port 721 or the circular jet port 711. In a side view, the outer peripheral edge of the side jet port 721 is spaced inward from the inner peripheral edge of the support portion 40 (i.e., toward the side closer to the two circular jet ports 711).

[0053] Gas supplied from the gas supply source 79 to the second gas supply unit 72 is injected from the side injection ports 721 in the Y direction (i.e., the scanning direction) toward the stage 21. This forms side airflows that flow in the Y direction toward the stage 21 around the two cylindrical airflows formed by the first gas supply unit 71. In this embodiment, gas is injected from the side injection ports 721 in the (-Y) direction (i.e., parallel to the scanning direction). The injection flow velocity of the gas from the side injection ports 721 (i.e., the flow velocity in the Y direction immediately after injection) is approximately the same as the injection flow velocity of the gas from each of the circumferential injection ports 711. Furthermore, the injection temperature of the gas from the side injection ports 721 (i.e., the temperature immediately after injection) is approximately the same as the injection temperature of the gas from each of the circumferential injection ports 711. The injection temperature of the gas from the circumferential injection port 711 and the side injection ports 721 is adjusted to, for example, 22.5°C by the temperature adjustment unit 76 described above.

[0054] As described above, in the drawing apparatus 1, the switching unit 77 switches the gas supply destination between the first gas supply unit 71 and the second gas supply unit 72 and the third gas supply unit 73. This allows gas to be selectively ejected from the circular jet port 711 and the side jet port 721, and from the upper jet port 731. Specifically, when the stage 21 is stationary at the standby position described above (for example, when the drawing apparatus 1 is idle), gas is ejected from the upper jet port 731, and gas is not ejected from the circular jet port 711 and the side jet port 721.

[0055] On the other hand, when stage 21 moves from the standby position and the position of stage 21 is measured by distance measuring device 26, gas is jetted from peripheral jet nozzle 711 and side jet nozzle 721, and gas is not jetted from upper jet nozzle 731. The gas supplied into housing 52 from peripheral jet nozzle 711, side jet nozzle 721, and upper jet nozzle 731 is sucked in by an exhaust unit (not shown) located at the end of housing 52 on the (-Y) side, for example, and exhausted to the outside of housing 52.

[0056] In the imaging device 1, when the stage 21 moves, motors and the like that serve as drive sources for the first moving mechanism 23 and the second moving mechanism 24 are operated. The motors and the like become heat sources that move together with the stage 21 and can affect the temperature of the atmosphere around the stage 21. Therefore, if the temperature fluctuates in the optical path of the laser light emitted from the distance measuring device 26 due to the influence of the motors and the like, the measurement accuracy of the position of the stage 21 may decrease. In addition, sensors and the like provided on the stage 21 and the like may also become heat sources.

[0057] As described above, in the imaging apparatus 1, the laser beam emitted from the distance measuring device 26 is surrounded by a cylindrical airflow formed by the first gas supply unit 71. The temperature of the gas ejected from the circular injection port 711 of the first gas supply unit 71 is adjusted by the temperature adjustment unit 76. By arranging the laser beam emitted from the distance measuring device 26 in the space inside the temperature-adjusted cylindrical airflow in this manner, temperature fluctuations on the optical path of the laser beam are suppressed. Therefore, refractive index fluctuations caused by the temperature fluctuations are suppressed, and the distance between the distance measuring device 26 and the stage 21 in the scanning direction is measured with high accuracy. As a result, the distance measuring device 26 can accurately measure the position of the stage 21.

[0058] 4A is a graph showing the measurement accuracy when the position of the stage 21 is measured by the distance measuring device 26 in a state in which gas is supplied from the first gas supply unit 71 and the second gas supply unit 72 and the supply of gas from the third gas supply unit 73 is stopped in the drawing apparatus 1. The horizontal axis of the graph represents the elapsed time (milliseconds) from the start of measurement, and the vertical axis represents the variation (nanometers) of the measurement value, which is the difference between the actual position of the stage 21 and the position of the stage 21 calculated based on the output from the distance measuring device 26 (i.e., the measured value of the position of the stage 21).

[0059] 4B is a graph of a comparative example showing the measurement accuracy when the distance measuring device 26 measures the position of the stage 21 in a state in which the supply of gas from the first gas supply unit 71 and the second gas supply unit 72 is stopped and gas is being supplied from the third gas supply unit 73 in the drawing apparatus 1. That is, FIG. 4B is a graph showing the measurement accuracy of the distance measuring device 26 in the gas supply state of the comparative example. The horizontal and vertical axes of FIG. 4B are the same as those in FIG. 4A. In the comparative example shown in FIG. 4B, the variation in the measurement values ​​of the distance measuring device 26 is approximately −200 nm to +200 nm. On the other hand, as shown in FIG. 4A, in the drawing apparatus 1 according to the present embodiment, the variation in the measurement values ​​of the distance measuring device 26 is limited to a range of −100 nm to +100 nm.

[0060] The distance measuring device 26 does not necessarily have to be provided in the drawing apparatus 1, but may be used to measure the position of the stage 21 in the scanning direction in a substrate processing apparatus that performs various types of processing on the substrate 9. In this case as well, by surrounding the laser light emitted from the distance measuring device 26 with the cylindrical airflow, it is possible to reduce the variation in the measurement values ​​of the distance measuring device 26.

[0061] As described above, the substrate processing apparatus (the drawing apparatus 1 in the example) includes the stage 21, a processing unit (the drawing unit 4 in the example), a stage moving mechanism 22, a distance measuring device 26, and a first gas supply unit 71. The stage 21 holds the substrate 9. The processing unit performs a predetermined process on the substrate 9. The stage moving mechanism 22 moves the stage 21 relative to the processing unit in a scanning direction (the Y direction in the example) parallel to the upper surface 91 of the substrate 9. The distance measuring device 26 is disposed on one side of the scanning direction of the stage 21 (the (+Y) side in the example) and spaced apart from the stage 21. The distance measuring device 26 measures the distance between the stage 21 and the stage 21 in the scanning direction by emitting laser light toward a surface to be measured (the side surface 211 in the example) perpendicular to the scanning direction of the stage 21 and receiving reflected light from the surface to be measured.

[0062] The first gas supply unit 71 injects gas toward the stage 21 along the scanning direction from a circular injection port 711 that is disposed at a distance from the stage 21 on the one side of the stage 21 in the scanning direction, thereby forming a cylindrical airflow that surrounds the laser light and flows toward the stage 21 along the scanning direction. This makes it possible to suppress temperature fluctuations on the optical path of the laser light emitted from the distance measuring device 26. As a result, the distance measuring device 26 can measure the position of the stage 21 with high accuracy.

[0063] As described above, it is preferable that the direction of gas injection from the circular injection port 711 is parallel to the laser light, so that the laser light can be suitably surrounded by the cylindrical airflow.

[0064] As described above, the flow velocity of the cylindrical airflow in the scanning direction is preferably greater than the movement velocity of the stage 21 in the scanning direction by the stage movement mechanism 22. This allows the cylindrical airflow ejected from the circular jet nozzle 711 to reach the stage 21 even when the stage 21 is moving in a direction away from the distance measuring device 26 and the circular jet nozzle 711 (in the above example, the (-Y) direction). Therefore, temperature fluctuations can be suppressed over substantially the entire length of the optical path of the laser light. As a result, the distance measuring device 26 can measure the position of the stage 21 with even greater accuracy.

[0065] As described above, the substrate processing apparatus (the drawing apparatus 1 in the example) preferably further includes a second gas supply unit 72. The second gas supply unit 72 is disposed on the one side of the stage 21 in the scanning direction (the (+Y) side in the example). The second gas supply unit 72 injects gas toward the stage 21 along the scanning direction from side injection ports 721 disposed around the circumferential injection port 711 in a side view parallel to the scanning direction, thereby forming a lateral airflow that flows toward the stage 21 along the scanning direction around the tubular airflow. By surrounding the tubular airflow with the lateral airflow in this manner, temperature fluctuations on the optical path of the laser light positioned inside the tubular airflow can be further suppressed. As a result, the position of the stage 21 can be measured by the distance measuring device 26 with even greater accuracy.

[0066] As described above, it is preferable that the gas injection flow velocity from the peripheral injection port 711 is the same as the gas injection flow velocity from the side injection port 721. This makes it possible to suppress the tubular airflow from being disturbed by the lateral airflow. As a result, it is possible to further suppress temperature fluctuations on the optical path of the laser light located inside the tubular airflow.

[0067] As described above, it is preferable that the temperature of the gas ejected from the circular injection port 711 is the same as the temperature of the gas ejected from the side injection port 721. This makes it possible to suppress fluctuations in the temperature of the cylindrical airflow due to side airflows. As a result, it is possible to further suppress temperature fluctuations on the optical path of the laser light located inside the cylindrical airflow.

[0068] As described above, the substrate processing apparatus (the drawing apparatus 1 in the above example) preferably further includes a support unit 40 that is gate-shaped in a side view. The support unit 40 is erected across the stage 21 and supports a processing unit (the drawing unit 4 in the above example) above the stage 21. Preferably, the entire side jet nozzle 721 is located inside the gate-shaped support unit 40 in a side view. This makes it possible to prevent the side airflow from colliding with the support unit 40. As a result, it is possible to prevent the side airflow from being disturbed, and also to prevent disturbance of the circumferential airflow caused by the disturbance of the side airflow.

[0069] As described above, it is preferable that the substrate processing apparatus (the drawing apparatus 1 in the example) further includes another distance measuring device 26. The other distance measuring device 26 is disposed at a distance from the stage 21 on the one side of the stage 21 in the scanning direction (the (+Y) side in the example). The other distance measuring device 26 measures the distance to the stage 21 in the scanning direction by emitting laser light toward the surface to be measured of the stage 21 (the side surface 211 in the example) and receiving light reflected from the surface to be measured. Furthermore, the first gas supply unit 71 injects gas from another circular injection port 711 toward the stage 21 along the scanning direction, thereby forming another cylindrical airflow that surrounds the laser light from the other distance measuring device 26 and flows toward the stage 21 along the scanning direction. The other circular injection nozzle 711 is positioned at a distance from the stage 21 on one side of the scanning direction of the stage 21, and is also positioned at a distance from the above-mentioned circular injection nozzle 711 on one side in a direction perpendicular to the scanning direction (in the above example, the (-X) side).

[0070] This allows the formation of multiple cylindrical air currents surrounding the laser beams emitted from the multiple distance measuring devices 26, respectively, and effectively suppresses temperature fluctuations along the optical path of each laser beam. As a result, measurements by each distance measuring device 26 can be performed with high accuracy, and the position of the stage 21 in the scanning direction and the orientation of the stage 21 can be measured with high accuracy.

[0071] As described above, the substrate processing apparatus (the drawing apparatus 1 in the above example) preferably further includes a third gas supply unit 73 that injects gas downward from the upper injection port 731 disposed above the stage 21. It is also preferable that gas be selectively injected from the circular injection port 711 and from the upper injection port 731. This makes it possible to form an appropriate airflow in accordance with the movement state of the stage 21 (for example, a state in which the stage 21 is moving and a state in which the stage 21 is waiting).

[0072] As described above, in the substrate processing apparatus, temperature fluctuations on the optical path of the laser light emitted from the distance measuring device 26 can be suppressed, and the distance measuring device 26 can accurately measure the position of the stage 21. Therefore, the structure of the substrate processing apparatus described above is particularly suitable for the drawing apparatus 1 that requires highly accurate detection of the position of the stage 21 (i.e., a substrate processing apparatus in which the processing section is the drawing section 4 that irradiates light onto the substrate 9 to draw a pattern).

[0073] The above-described drawing device 1 can be modified in various ways.

[0074] For example, the surface to be measured does not necessarily have to be the side surface of the stage 21, but may be another structure that moves together with the stage 21 (for example, a reflecting mirror fixed to the stage 21).

[0075] The third gas supply unit 73 may be omitted from the drawing apparatus 1. In this case, gas is supplied to the inside of the housing 52 from the first gas supply unit 71 and the second gas supply unit 72 regardless of the movement state of the stage 21.

[0076] In the drawing apparatus 1, the number of distance measuring devices 26 may be one or may be three or more. When the number of distance measuring devices 26 is one, the number of the circular injection ports 711 provided in the first gas supply unit 71 may also be one.

[0077] The shape of the circumferential injection port 711 in a side view is not necessarily limited to a substantially circular shape, and may be changed in various ways as long as it is circumferential.

[0078] The direction of gas injection from the circular injection port 711 does not necessarily have to be parallel to the laser light. For example, the injection direction may be inclined toward the (-Z) side with respect to the laser light. In other words, gas may be injected from the circular injection port 711 in both the (-Y) direction and the (-Z) direction.

[0079] The flow velocity in the Y direction of the cylindrical airflow injected from the circumferential injection port 711 may be equal to or less than the movement velocity in the Y direction of the stage 21 by the stage movement mechanism 22 .

[0080] The gas jet flow velocity from the circumferential jet nozzle 711 may be different from the gas jet flow velocity from the side jet nozzles 721. In addition, the gas jet temperature from the circumferential jet nozzle 711 may be different from the gas jet temperature from the side jet nozzles 721.

[0081] The side injection ports 721 of the second gas supply unit 72 do not necessarily need to be located entirely inside the support unit 40 in a side view, and may partially overlap the support unit 40. Furthermore, as long as the side injection ports 721 are arranged around the circumferential injection port 711, they do not necessarily need to surround the (+Z) side, (+X) side, and (-X) side of the circumferential injection port 711, and their shape may be modified in various ways. The second gas supply unit 72 may be omitted.

[0082] In the imaging device 1, in order to measure the position of the stage 21 in the X direction (i.e., the sub-scanning direction), a distance measuring device (i.e., a laser interferometer) substantially similar to the distance measuring device 26 described above may be provided, for example, on the (+X) side of the stage 21 at a distance from the stage 21. The distance measuring device measures the distance between the stage 21 and itself in the X direction by emitting laser light toward a side surface on the (+X) side of the stage 21 and receiving reflected light from the side surface. In this case, a circumferential jet nozzle substantially similar to the circumferential jet nozzle 711 described above is provided on the (+X) side of the stage 21 at a position spaced from the stage 21. The circumferential jet nozzle has a substantially circumferential shape substantially perpendicular to the X direction, and by injecting gas toward the stage 21 along the X direction, forms a cylindrical airflow that surrounds the periphery of the laser light and flows toward the stage 21 along the X direction. This allows the position of the stage 21 in the X direction to be measured with high accuracy. Two or more pairs of the distance measuring device and the circumferential jet nozzle may be provided along the Y direction.

[0083] The distance measuring device 26 described above may be a measuring device having a structure other than a laser interferometer.

[0084] As described above, the above-described structure of the drawing apparatus 1 may be applied to a substrate processing apparatus that performs processing other than drawing processing on the substrate 9. For example, the above-described distance measuring device 26 and first gas supply unit 71 may be provided in a marking apparatus that performs laser marking on an object, or an inspection apparatus that performs a predetermined inspection on an object.

[0085] The configurations in the above-described embodiment and each modification may be combined as appropriate as long as they are not mutually contradictory.

[0086] While the invention has been particularly illustrated and described, it should be understood that the foregoing description is illustrative and not restrictive, and that numerous modifications and variations are possible without departing from the scope of the invention.

[0087] REFERENCE SIGNS LIST 1 lithography device 4 lithography unit 9 substrate 21 stage 22 stage movement mechanism 26 distance measuring device 40 support unit 71 first gas supply unit 72 second gas supply unit 73 third gas supply unit 211 side surface (of stage) 711 circumferential jet nozzle 721 side jet nozzle 731 upper jet nozzle

Claims

1. A substrate processing apparatus comprising: a stage for holding a substrate; a processing section for performing a predetermined process on the substrate; a stage movement mechanism for moving the stage relative to the processing section in a scanning direction parallel to an upper surface of the substrate; a distance measuring device arranged on one side of the stage in the scanning direction and spaced apart from the stage, and measuring the distance to the stage in the scanning direction by emitting laser light toward a surface to be measured that is perpendicular to the scanning direction of the stage and receiving reflected light from the surface to be measured; and a first gas supply unit that sprays gas toward the stage along the scanning direction from a circular injection port arranged on one side of the stage in the scanning direction and spaced apart from the stage, thereby forming a cylindrical airflow that surrounds the periphery of the laser light and flows toward the stage along the scanning direction.

2. A substrate processing apparatus according to claim 1, wherein the direction of gas injection from said circumferential injection port is parallel to said laser light.

3. A substrate processing apparatus according to claim 1, wherein the flow velocity of the cylindrical airflow in the scanning direction is greater than the moving speed of the stage in the scanning direction by the stage moving mechanism.

4. A substrate processing apparatus as described in claim 1, further comprising a second gas supply unit that sprays gas toward the stage along the scanning direction from side injection ports that are arranged on one side of the stage in the scanning direction and that are arranged around the circumferential injection port in a side view parallel to the scanning direction, thereby forming a lateral airflow that flows toward the stage along the scanning direction around the tubular airflow.

5. A substrate processing apparatus according to claim 4, wherein the gas jet flow rate from said peripheral jet nozzle is the same as the gas jet flow rate from said side jet nozzles.

6. A substrate processing apparatus according to claim 4, wherein the temperature of the gas injected from said peripheral injection nozzle is the same as the temperature of the gas injected from said side injection nozzles.

7. A substrate processing apparatus according to claim 4, further comprising a support part that supports the processing part above the stage and that is gate-shaped in a side view and stands across the stage, and the entire side injection nozzle is located inside the gate-shaped support part in a side view.

8. A substrate processing apparatus as defined in claim 1, further comprising another distance measuring device arranged on one side of the stage in the scanning direction at a distance from the stage, and measuring the distance to the stage in the scanning direction by emitting laser light toward the surface to be measured of the stage and receiving reflected light from the surface to be measured, wherein the first gas supply unit injects gas toward the stage along the scanning direction from another circular injection port arranged on one side of the scanning direction of the stage at a distance from the stage and arranged at a distance from the circular injection port to one side in a direction perpendicular to the scanning direction, thereby forming another cylindrical airflow that surrounds the laser light from the other distance measuring device and flows toward the stage along the scanning direction.

9. A substrate processing apparatus according to claim 1, further comprising a third gas supply unit that injects gas downward from an upper injection port located above the stage, wherein gas is selectively injected from the circular injection port and gas is injected from the upper injection port.

10. A substrate processing apparatus according to any one of claims 1 to 9, wherein the processing section is a drawing section that draws a pattern by irradiating light onto the substrate.

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