Optical apparatus and drawing apparatus

Abstract

The invention provides an optical apparatus and a drawing apparatus, which can simplify the structure of a cooling part for cooling a digital micromirror device and cool the digital micromirror device. The DMD (6) has a DMD base part (61), a DMD mirror part, and a DMD cover part (63). The DMD mirror unit includes a plurality of movable micromirrors arranged in a matrix on the (-Z) side of the DMD base unit (61). The DMD cover section (63) covers the DMD mirror section (62) from one side in the thickness direction. The cooling section (7) has a back surface cooling section (71) and a biasing section (72). The rear surface cooling unit (71) is in contact with the (+ Z)-side main surface of the DMD base unit (61), and cools the DMD (6) by heat conduction. The biasing section (72) is in contact with the back surface cooling section (71) from the (+ Z) side. The biasing section (72) biases the rear surface cooling section (71) toward the (+ Z)-side main surface of the DMD base section (61) by being connected to the support substrate (60). As a result, the structure of the back cooling unit (71) can be simplified and the DMD (6) can be cooled.

Description

Technical Field

[0001] The present invention relates to an optical device for irradiating modulated light onto an object, and a drawing device having the optical device and irradiating light onto a substrate to draw a pattern.

[0002] [Reference to related applications]

[0003] This application claims the benefit of priority of Japanese patent application JP2023-133578 filed on August 18, 2023, and incorporates the entire disclosure of that application into this application. Background Art

[0004] Conventionally, when drawing patterns on printed circuit boards, semiconductor substrates, etc. (hereinafter referred to as "substrates"), a drawing device is used that irradiates a photosensitive material formed on the substrate with modulated light and directly draws the pattern by scanning the irradiated area with the light.

[0005] In such a drawing device, a digital micromirror device (DMD) is used as one of the light modulators for modulating light in a drawing head that emits light toward a substrate. When the drawing device is operating, the temperature of the DMD rises due to the heat generated by the operation of the DMD and the heat generated by the light irradiated to the reflective mirror portion of the DMD. When the temperature of the DMD deviates from the range of the prescribed operating temperature conditions, the quality of the DMD may deteriorate prematurely, so the DMD is sometimes cooled in the drawing device. For example, in the device of the specification of the Chinese Utility Model Publication No. 216671613 (Document 1), as Figure 3 As shown, in the DMD unit 5, the water cooling block 2 is brought into contact with the side of the DMD chip opposite to the reflective mirror portion to cool the DMD.

[0006] However, in the device of document 1, a flange portion extending outward from the main body of the water-cooling block 2 is provided, and a through hole for threaded fixing is provided in the flange portion. The flange portion is threadedly fixed to the adapter plate 4 between the DMD assembly 5 and the water-cooling block 2 by means of a screw inserted into the through hole. In addition, in the device, a spring is provided for inserting the screw, and the water-cooling block 2 is used to apply force to the adapter plate 4. In this way, the cooling block 2 can be properly contacted with the DMD assembly 5 via the adapter plate 4, but the structure of the cooling block 2 is complicated, and the manufacturing difficulty of the optical device including the DMD increases. Summary of the invention

[0007] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to cool the digital micromirror device while simplifying the structure of a cooling unit that cools the digital micromirror device.

[0008] Mode 1 of the present invention is an optical device for irradiating modulated light to an object, wherein the device comprises: an illumination optical system into which light emitted from a light source is incident; a light modulator for modulating the light guided by the illumination optical system; and a projection optical system for guiding the light modulated by the light modulator toward the object. The light modulator comprises: a digital micromirror device; a supporting substrate provided with a through hole on which the digital micromirror device is mounted; and a cooling unit for cooling the digital micromirror device. The digital micromirror device comprises: a DMD base unit; a DMD reflector unit including a plurality of movable micromirrors arranged in a matrix on one side in the thickness direction of the DMD base unit; and a DMD cover unit covering the DMD reflector unit from the one side in the thickness direction. The cooling part comprises: a back cooling part, which contacts the main surface on the other side of the thickness direction of the DMD base part and uses heat conduction to cool the digital micromirror device; and a force applying part, which contacts the back cooling part from the other side of the thickness direction and is connected to the supporting substrate, so as to apply force to the back cooling part toward the main surface on the other side of the thickness direction of the DMD base part.

[0009] According to the present invention, it is possible to cool the digital micromirror device while simplifying the structure of the back surface cooling unit.

[0010] In a second aspect of the present invention, according to the optical device of the first aspect, the force-applying portion is indirectly connected to the support substrate by being connected to an intermediate member protruding from the support substrate to the other side in the thickness direction. The portion where the force-applying portion and the intermediate member are connected is closer to the other side in the thickness direction than the end of the other side of the back cooling portion.

[0011] Mode 3 of the present invention is an optical device according to Mode 1 (or Mode 1 or 2), wherein the force-applying portion is indirectly connected to the support substrate by being connected to an intermediate member protruding from the support substrate to the other side in the thickness direction. The intermediate member has a pair of support portions, and the pair of support portions extend along the side surface of the back cooling portion in the thickness direction and support the back cooling portion by sandwiching the back cooling portion. The force-applying portion is connected to the end of the other side of the pair of support portions in the thickness direction.

[0012] Mode 4 of the present invention is an optical device according to Mode 1 (or any one of Modes 1 to 3), wherein the force-applying portion is indirectly connected to the support substrate by being connected to an intermediate member protruding from the support substrate to the other side in the thickness direction. The intermediate member has a door-shaped protrusion that protrudes from the support substrate to the other side in the thickness direction and opens toward the support substrate. The force-applying portion is connected to the end of the other side of the protrusion in the thickness direction.

[0013] In a fifth aspect of the present invention, according to the optical device of the first aspect (or any one of the first to fourth aspects), the back cooling portion and the force applying portion are each rectangular in a plan view parallel to the thickness direction. A pair of long sides of the force applying portion are orthogonal to a pair of long sides of the back cooling portion in a plan view. Both ends of the force applying portion in a direction parallel to the pair of long sides of the force applying portion are connected to the support substrate.

[0014] According to mode 6 of the present invention, in an optical device according to mode 1 (or any one of modes 1 to 5), the light modulator also has a cylindrical containing member with a cover, the containing member is arranged on the other side of the supporting substrate in the thickness direction, covers the back cooling portion and contains the back cooling portion in the internal space, and dry gas is supplied to the internal space.

[0015] Mode 7 of the present invention is an optical device according to Mode 1 (or any one of Modes 1 to 6), wherein the cooling unit further comprises a front cooling unit, wherein the front cooling unit forms an airflow along the main surface of the one side in the thickness direction of the DMD cover unit to cool the digital micromirror device.

[0016] According to an eighth aspect of the present invention, in the optical device of the seventh aspect, a flow direction of the airflow formed by the front cooling portion is parallel to the main surface on the one side in the thickness direction of the DMD cover portion.

[0017] According to a ninth aspect of the present invention, in the optical device of the seventh aspect (or the seventh or eighth aspect), the incident direction of light on the digital micromirror device is inclined in a lateral direction perpendicular to the thickness direction relative to the thickness direction. The flow direction of the airflow formed by the front cooling unit is parallel to the lateral direction.

[0018] Mode 10 of the present invention is an optical device according to Mode 7 (or any one of Modes 7 to 9), wherein the airflow formed by the front cooling portion includes: a first airflow, flowing from one lateral side perpendicular to the thickness direction to the other side; and a second airflow, flowing from the other lateral side to the one side.

[0019] Mode 11 of the present invention is an optical device according to Mode 10, wherein the position of the first ejection port forming the first airflow and the position of the second ejection port forming the second airflow are different from each other in a direction perpendicular to the thickness direction and the lateral direction.

[0020] Method 12 of the present invention is a drawing device for drawing a pattern by irradiating light on a substrate, wherein the device comprises: a stage for holding the substrate; an optical device described in any one of methods 1 to 11 for irradiating modulated light on the substrate; and a scanning mechanism for moving the stage relative to the optical device in a scanning direction parallel to the main surface of the substrate.

[0021] The above-mentioned objects and other objects, features, aspects and advantages will become clearer with reference to the accompanying drawings and the following detailed description of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a perspective view showing a drawing device according to one embodiment.

[0023] Figure 2 It is a side view depicting the head.

[0024] Figure 3 It is a side view of the light modulation unit.

[0025] Figure 4 It is a three-dimensional diagram of the light modulation unit.

[0026] Figure 5 It is a three-dimensional diagram of the light modulation unit.

[0027] Figure 6 This is a bottom view of the light modulation unit.

[0028] Figure 7 It is a side view of another light modulation unit.

[0029] Description of Reference Numerals

[0030] 1Drawing device

[0031] 6DMD (Digital Micromirror Device)

[0032] 7Cooling section

[0033] 8. Accommodating components

[0034] 9 substrates

[0035] 10. Optical Device

[0036] 21 stage

[0037] 22 Stage moving mechanism

[0038] 43 Illumination optical system

[0039] 44, 44a light modulation unit

[0040] 45 Projection optical system

[0041] 60 Support substrate

[0042] 61DMD base unit

[0043] 62DMD reflector unit

[0044] 63DMD cover

[0045] 71, 71a Back side cooling unit

[0046] 72, 72a force application part

[0047] 74 front cooling unit

[0048] 80 Interior Space

[0049] 421 Light Source

[0050] 601 through hole

[0051] 612 Main surface (DMD base portion)

[0052] 631 Main surface (DMD cover)

[0053] 722 Intermediate Components

[0054] 727 Support

[0055] 727a Upper end portion (of the support portion)

[0056] 743 First Exhaust Port

[0057] 744 Second Exhaust Port DETAILED DESCRIPTION

[0058] Figure 1 1 is a perspective view showing a drawing device 1 according to an embodiment of the present invention. The drawing device 1 is a direct drawing device that irradiates a photosensitive material on a substrate 9 with a substantially light beam after spatial modulation and scans the irradiation area of ​​the light on the substrate 9 to draw a pattern. Figure 1 In FIG. 1 , three directions orthogonal to each other are indicated by arrows as the X direction, the Y direction, and the Z direction. Figure 1 In the example shown, the X direction and the Y direction are horizontal directions perpendicular to each other, and the Z direction is a vertical direction (ie, an up-and-down direction). The same is true in other figures.

[0059] The substrate 9 is, for example, a printed circuit board in a substantially rectangular flat plate shape. On the main surface (hereinafter, also referred to as "upper surface 91") on the (+Z) side of the substrate 9, a resist film formed of a photosensitive material is provided on the copper layer. In the drawing device 1, a circuit pattern is drawn (i.e., formed) on the resist film of the substrate 9. It should be noted that the type and shape of the substrate 9 can be variously changed.

[0060] The drawing device 1 includes: a stage 21, a stage moving mechanism 22, an alignment unit 3, and a drawing unit 4. The stage 21 is a roughly rectangular flat plate-shaped member arranged on the lower side (i.e., the (-Z) side) than the alignment unit 3 and the drawing unit 4. The stage 21 has a substrate holding portion 25 that holds the substrate 9 in a horizontal state from the lower side. The substrate holding portion 25 is, for example, a vacuum chuck that absorbs and holds the lower surface of the substrate 9. The substrate holding portion 25 may have a structure other than a vacuum chuck, for example, it may be a mechanical chuck. The upper surface 91 of the substrate 9 placed on the substrate holding portion 25 is roughly perpendicular to the Z direction and roughly parallel to the X direction and the Y direction.

[0061] The stage moving mechanism 22 is a moving mechanism that moves the stage 21 relative to the alignment section 3 and the drawing section 4 in the horizontal direction (i.e., a direction roughly parallel to the upper surface 91 of the substrate 9). The stage moving mechanism 22 is installed on the upper surface of the base 11 and is supported by the base 11 from the bottom. The stage moving mechanism 22 has a first moving mechanism 23 and a second moving mechanism 24. The second moving mechanism 24 supports the stage 21 from the bottom and moves the stage 21 linearly in the X direction along the guide rail. The first moving mechanism 23 supports the second moving mechanism 24 from the bottom and moves the stage 21 linearly in the Y direction along the guide rail together with the second moving mechanism 24. The driving source of the first moving mechanism 23 and the second moving mechanism 24 is, for example, a linear servo motor or a driving source in which a motor is mounted on a ball screw. The structures of the first moving mechanism 23 and the second moving mechanism 24 can be changed in various ways.

[0062] The drawing device 1 may be provided with a stage rotating mechanism that rotates the stage 21 around a rotation axis extending in the Z direction. In addition, the drawing device 1 may be provided with a stage lifting mechanism that moves the stage 21 in the Z direction. As the stage rotating mechanism, for example, a servo motor may be used. As the stage lifting mechanism, for example, a linear servo motor may be used. The structures of the stage rotating mechanism and the stage lifting mechanism may be modified in various ways.

[0063] The alignment unit 3 has a plurality of alignment cameras 31. Figure 1In the example shown, two alignment cameras 31 are arranged in the X direction, but only the alignment camera 31 on the (+X) side is shown. Each alignment camera 31 is supported above the stage 21 and the stage moving mechanism 22 by a support portion 27 provided across the stage 21 and the stage moving mechanism 22. The support portion 27 is, for example, a single metal member provided at one position in the Y direction. Figure 1 In the illustrated example, the support portion 27 is a door-shaped member (so-called gantry) spanning the stage 21 and the stage moving mechanism 22 , and is vertically provided on the upper surface of the base 11 .

[0064] exist Figure 1 In the example shown, two alignment cameras 31 are mounted on the side surface of the (+Y) side of the support portion 27. Of the two alignment cameras 31, for example, one alignment camera 31 is fixed to the support portion 27, and the other alignment camera 31 can be moved along the X direction on the support portion 27. Thus, the distance in the X direction between the two alignment cameras 31 can be changed. It should be noted that the number of alignment cameras 31 of the alignment portion 3 can be one, or three or more.

[0065] Each alignment camera 31 captures an alignment mark (not shown) pre-set on the upper surface 91 of the substrate 9. In the drawing device 1, the substrate 9 is aligned (i.e., the relative position of the substrate 9 with respect to the drawing head 41 is corrected) based on the image of the alignment mark acquired by the alignment camera 31.

[0066] The drawing unit 4 has a plurality of (in Figure 1 In the example shown, there are six drawing heads 41. The plurality of drawing heads 41 have substantially the same structure. Each drawing head 41 has a light modulator that irradiates modulated (i.e., spatially modulated) light downward. Each drawing head 41 is supported by the support portion 27 above the stage 21 and the stage moving mechanism 22. Figure 1 In the example shown, six drawing heads 41 are mounted on the side surface of the (-Y) side of the support portion 27. It should be noted that the alignment camera 31 may be supported by a support portion different from the support portion 27 to which the drawing heads 41 are mounted.

[0067] exist Figure 1In the example shown, six drawing heads 41 are arranged in a substantially straight line substantially parallel to the X direction. The positions of the six drawing heads 41 in the Y direction and the Z direction are substantially the same. It should be noted that the plurality of drawing heads 41 do not necessarily need to be arranged in a straight line, and for example, they may be arranged in a staggered manner. In the case where the drawing heads 41 are arranged in a staggered manner, for example, the plurality of drawing heads 41 are arranged substantially parallel to the X direction at a first position in the Y direction, and at a second position adjacent to the (-Y) side of the first position, the drawing heads 41 are arranged between the plurality of drawing heads 41 in the X direction. In addition, in the drawing unit 4, the number of the drawing heads 41 may be one, or may be two or more.

[0068] In the drawing device 1, pattern drawing on the substrate 9 is performed in a so-called multi-path method. Specifically, modulated light is irradiated onto the upper surface 91 of the substrate 9 from the plurality of drawing heads 41 of the drawing unit 4, and the substrate 9 is moved in the Y direction and passes under the drawing heads 41 by the first moving mechanism 23 of the stage moving mechanism 22. Thus, the irradiation area of ​​the light from the plurality of drawing heads 41 is scanned on the substrate 9 in the Y direction, and the substrate 9 is drawn. Next, the substrate 9 is moved stepwise by a predetermined distance in the X direction by the second moving mechanism 24. Then, the substrate 9 is moved in the Y direction by the first moving mechanism 23 again, and light is irradiated from the drawing heads 41 to the substrate 9 in parallel with the movement, and the substrate 9 is drawn. In the drawing device 1, a pattern is drawn on the substrate 9 by alternately irradiating the substrate 9 moving in the Y direction with light and stepping the substrate 9 in the X direction.

[0069] In the following description, the Y direction is referred to as the "main scanning direction" or "scanning direction", and the X direction is referred to as the "sub-scanning direction" or "width direction". The main scanning direction and the sub-scanning direction are directions substantially parallel to the upper surface 91 of the substrate 9. In the stage moving mechanism 22, the first moving 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 moving mechanism 24 is a sub-scanning mechanism that moves the stage 21 relative to the drawing head 41 in the sub-scanning direction.

[0070] It should be noted that, in the drawing device 1, the substrate 9 may be drawn in a single-path method (also referred to as a single-path method) in which the drawing of the pattern on the substrate 9 is completed by moving the substrate 9 only once relative to the drawing head 41 in the Y direction. In this case, when drawing the pattern, the sub-scanning (i.e., the stepping movement in the X direction) of the substrate 9 by the second moving mechanism 24 is not performed. That is, the stage moving mechanism 22 is a scanning mechanism that moves the stage 21 at least in the scanning direction relative to the drawing head 41.

[0071] Figure 2This is a side view of a drawing head 41 enlarged and observed from the (+X) side. The drawing head 41 includes a light source unit 42, an illumination optical system 43, a light modulation unit 44, a projection optical system 45, and a drawing head cover 46. The light source unit 42, the illumination optical system 43, the light modulation unit 44, and the projection optical system 45 are accommodated inside the drawing head cover 46. Figure 2 In order to facilitate understanding of the drawings, the head cover 46 is shown in cross section, and the internal structure of the head cover 46 is shown by solid lines. Figure 2 The support portion 27 is also shown.

[0072] exist Figure 2 In the example shown, the drawing head cover 46 is a member that is substantially L-shaped when viewed from the side. The light source unit 42 is arranged inside the drawing head cover 46 at the end portion on the (+Y) side of the upper portion of the drawing head 41. The illumination optical system 43 is arranged inside the drawing head cover 46 at the (-Y) side of the light source unit 42 at the upper portion of the drawing head 41. The illumination optical system 43 extends substantially parallel to the Y direction. The light modulation unit 44 is arranged inside the drawing head cover 46 at the end portion on the (-Y) side of the upper portion of the drawing head 41. The light modulation unit 44 is located on the (-Y) side of the illumination optical system 43.

[0073] The projection optical system 45 is disposed inside the drawing head cover 46 at the end of the drawing head 41 on the (-Y) side, on the (-Z) side (i.e., below) of the light modulation unit 44. The projection optical system 45 extends substantially parallel to the Z direction. Figure 2 In the example shown, the lower end of the drawing head cover 46 is open, and the lower end of the projection optical system 45 protrudes downward from the lower end opening of the drawing head cover 46. A focus sensor for adjusting the focus of the drawing head 41 may be provided near the lower end of the projection optical system 45.

[0074] The shape of the drawing head cover 46 may be changed in various ways. For example, the drawing head cover 46 may be a member extending substantially parallel to the Z direction. In this case, the illumination optical system 43 and the light source unit 42 are disposed on the (+Z) side of the light modulation unit 44 .

[0075] Light emitted from the light source unit 42 is incident on the illumination optical system 43 along a predetermined optical axis J1 of the drawing head 41, and is guided to the light modulation unit 44 via the illumination optical system 43 and the reflection mirrors 471, 472, etc. Figure 2 The optical axis J1 is depicted by a dot-dash line. The light modulator 44 modulates the light from the light source 42 and guides it to the projection optical system 45. The light modulated by the light modulator 44 is projected by the projection optical system 45 toward the upper surface 91 (refer to FIG. 1 ) of the object, that is, the substrate 9, which is located below the drawing head 41 (i.e., in the (-Z) direction). Figure 1 )guide.

[0076] The light source unit 42 has a light source 421 such as an LED (Light Emitting Diode) or an LD (Laser Diode). The illumination optical system 43 has optical elements such as a plurality of lenses arranged roughly parallel to the Y direction. The light modulation unit 44 has a digital micromirror device 6 (hereinafter also referred to as "DMD6") as a spatial light modulator. The projection optical system 45 has optical elements such as a plurality of lenses arranged roughly parallel to the Z direction.

[0077] It should be noted that in Figure 2 In the example shown, one light source 421 is depicted in the light source unit 42, but the number of light sources 421 provided in the light source unit 42 may be plural. For example, plural light sources 421 emitting light of different wavelengths may be provided in the light source unit 42. In this case, when drawing a pattern on the substrate 9, one or more light sources 421 among the plural light sources 421 are selected to be used in accordance with the type of photosensitive material on the substrate 9. It should be noted that the light source 421 provided in the light source unit 42 is not limited to LEDs and LDs, and various types of light sources may be used.

[0078] In the drawing device 1, the illumination optical system 43, the light modulator 44 and the projection optical system 45 constitute an optical device 10 for irradiating modulated light to an object (i.e., substrate 9). It should be noted that the optical device 10 may also include other structures such as a light source unit 42 and a drawing head cover 46.

[0079] Figure 3 It is a side view showing the light modulation unit 44 in an enlarged manner. Figure 4 It is a perspective view of the light modulation unit 44 as viewed from obliquely above. Figure 5 The optical modulation unit 44 is a perspective view viewed from below. The optical modulation unit 44 includes the above-mentioned DMD 6, the support substrate 60, the cooling unit 7, and the container member 8. The container member 8 is a cover member provided on the (+Z) side of the support substrate 60 and covering the cooling unit 7 and the like. Figure 3 In FIG. 8 , the receiving member 8 is shown in cross section. Figure 4 and Figure 5 The receiving member 8 is shown by dashed lines.

[0080] The support substrate 60 is a roughly flat plate-shaped member extending roughly perpendicularly to the Z direction, and is used to support the DMD 6 and the cooling unit 7. The shape of the support substrate 60 when viewed from above (i.e., the shape when viewed from the (+Z) side parallel to the Z direction) is, for example, roughly rectangular. The support substrate 60 is provided with a through hole 601 that passes through the support substrate 60 in the Z direction. The shape of the through hole 601 when viewed from above is, for example, roughly circular. Figures 3 to 5In the example shown, the portion around the through hole 601 in the support substrate 60 is thicker in the Z direction than other portions of the support substrate 60 (eg, the end portion on the (+Y) side and the end portion on the (−Y) side).

[0081] The DMD 6 is a substantially rectangular member in a plan view. The DMD 6 is mounted from above on a through hole 601 provided on the support substrate 60. In other words, the DMD 6 is mounted on the upper surface (i.e., the main surface on the (+Z) side) of the support substrate 60 in a manner overlapping with the through hole 601 in a plan view. That is, the support substrate 60 is a device holding portion that holds the DMD 6.

[0082] The DMD 6 has a DMD base portion 61, a DMD reflector portion 62, and a DMD cover portion 63. The DMD base portion 61 is a roughly flat member extending roughly perpendicularly to the Z direction. That is, the Z direction is the thickness direction of the DMD base portion 61, and is also the thickness direction of the DMD 6. The shape of the DMD base portion 61 when viewed from above is, for example, roughly rectangular. The DMD base portion 61 is in direct or indirect contact with the upper surface of the support substrate 60 and is supported from below by the support substrate 60. The DMD base portion 61 is provided with a receiving portion for receiving a driving signal input from the outside of the DMD 6, and a driving portion for driving the DMD reflector portion 62 based on the driving signal, etc.

[0083] The DMD reflector 62 is provided on the main surface 611 on the (-Z) side of the DMD base 61. The shape of the DMD reflector 62 when viewed from above is, for example, a substantially rectangular shape. The size of the DMD reflector 62 when viewed from above is smaller than the size of the DMD base 61 when viewed from above. The DMD reflector 62 is entirely covered by the DMD base 61 from the (+Z) side.

[0084] The DMD reflector unit 62 has a plurality of movable micro-mirrors (not shown) arranged in a matrix. The plurality of micro-mirrors are driven independently of each other by the above-mentioned driving unit arranged on the DMD base unit 61, and can switch between an on state and an off state. The plurality of micro-mirrors are arranged in a roughly planar shape at roughly the same position in the Z direction. The plurality of micro-mirrors are arranged roughly parallel in the X direction and the Y direction, for example. The DMD reflector unit 62 is arranged inside the through hole 601 of the support substrate 60. The lower surface of the DMD reflector unit 62 is located at a position lower than the upper surface of the support substrate 60 around the through hole 601 and at a position higher than the lower surface of the support substrate 60 around the through hole 601.

[0085] In the optical modulation section 44, the light guided to the DMD6 is incident on the DMD6 from the (-Z) side of the DMD6, is reflected by the DMD reflector section 62 and is guided to the (-Z) side of the DMD6. That is, the (-Z) side of the DMD6 (i.e., one side in the thickness direction) is the incident side (i.e., the front side) on which the above-mentioned light is incident, and the (+Z) side of the DMD6 (i.e., the other side in the thickness direction) is the back side located on the opposite side of the incident side of the light. The principal surface 612 on the (+Z) side of the DMD base section 61 is also the principal surface on the (+Z) side of the DMD6, and is also referred to as the "back side 612 of the DMD6" in the following description. The principal surface 612 on the (+Z) side of the DMD base section 61 is a roughly flat surface that is roughly perpendicular to the Z direction.

[0086] The DMD cover 63 is a light-transmitting member that covers the plurality of micro-mirrors of the DMD reflector 62 from below. The DMD cover 63 is, for example, a roughly rectangular or flat member with an opening on the (+Z) side. The DMD cover 63 is mounted on the main surface 611 on the (-Z) side of the DMD base 61. The DMD cover 63 is, for example, a glass cover made of transparent quartz glass. The light incident on the DMD 6 is incident on the DMD reflector 62 through the DMD cover 63. In addition, the light reflected by the DMD reflector 62 is guided to the outside of the DMD 6 through the DMD cover 63.

[0087] The DMD cover 63 is arranged inside the through hole 601 of the support substrate 60. The main surface 631 (i.e., the lower surface) on the (-Z) side of the DMD cover 63 is located below the upper surface of the support substrate 60 around the through hole 601 and above the lower surface of the support substrate 60 around the through hole 601. The main surface 631 on the (-Z) side of the DMD cover 63 is a substantially flat surface substantially perpendicular to the Z direction.

[0088] The cooling unit 7 is a mechanism for cooling the DMD 6. The cooling unit 7 includes a back cooling unit 71, a force applying unit 72, and a front cooling unit 74. The back cooling unit 71 is located at a position overlapping with the DMD 6 in a plan view and is arranged on the (+Z) side of the DMD 6 (i.e., opposite to the DMD 6). Figure 1The back cooling unit 71 is in contact with the main surface 612 (i.e., the upper surface) on the (+Z) side of the DMD base unit 61, and cools the DMD6 from the DMD base unit 61 side by heat conduction. The force-applying unit 72 is a component that applies force to the back cooling unit 71 toward the main surface 612 (i.e., the back side 612 of the DMD6) on the (+Z) side of the DMD base unit 61. The front cooling unit 74 is arranged on the (-Z) side of the DMD6, and forms an airflow that flows along the main surface 631 (i.e., the lower surface) on the (-Z) side of the DMD cover unit 63, and cools the DMD6 from the DMD cover unit 63 side. The main surface 631 on the (-Z) side of the DMD cover unit 63 is also the main surface on the (-Z) side of the DMD6, and is also referred to as the "front face 631 of the DMD" in the following description.

[0089] The back cooling unit 71 is a roughly rectangular parallelepiped component having a flow path 710 disposed therein, and is a cooling jacket in which a fluid refrigerant flows in the flow path 710. The refrigerant is, for example, a liquid such as water. The refrigerant may also be a liquid other than water, a gas, or a two-phase fluid obtained by mixing a liquid and a gas. In the present embodiment, the back cooling unit 71 is a water-cooling jacket in which water flows in the flow path 710. Figure 4 In the example shown, on the upper surface of the back cooling portion 71 (i.e., the surface on the (+Z) side), water flows into the flow path 710 from the opening provided at the end on the (+X) side, and on the upper surface of the back cooling portion 71, the water in the flow path 710 is discharged from the opening provided at the end on the (-X) side.

[0090] exist Figures 3 to 5 In the example shown, the shape of the back cooling portion 71 when viewed from above is a roughly rectangular shape in which the length in the X direction is longer than the length in the Y direction. In other words, the shape of the back cooling portion 71 when viewed from above is a roughly rectangular shape having a pair of long sides roughly parallel to the X direction and a pair of short sides roughly parallel to the Y direction. The length of the back cooling portion 71 in the X direction is roughly constant except for the lower end portion of the back cooling portion 71 (i.e., the end portion on the (-Z) side), and decreases at the lower end portion of the back cooling portion 71. In the back cooling portion 71, a convex portion is provided at the lower end portion, which protrudes downward (i.e., toward the back side 612 of the DMD 6) from the approximate center portion in the X direction. The lower end surface of the convex portion is indirectly in contact with the main surface 612 on the (+Z) side of the DMD base portion 61 via a sheet-like heat transfer member 711. The heat transfer member 711 is a heat sink with a relatively high thermal conductivity. It should be noted that the shape of the back cooling portion 71 can be changed in various ways. In addition, the back surface cooling unit 71 may be in direct contact with the main surface 612 on the (+Z) side of the DMD base unit 61 without the intermediary of the heat transfer member 711 or the like.

[0091] The force applying portion 72 is a substantially flat plate-shaped member disposed on the (+Z) side of the back cooling portion 71. The force applying portion 72 contacts the upper surface of the back cooling portion 71 from the (+Z) side (i.e., the other side in the thickness direction of the DMD base portion 61). Figure 3 and Figure 4 In the example shown, the force applying portion 72 is in indirect contact with the upper surface of the back cooling portion 71 via a substantially rectangular parallelepiped heat insulating member 721. The heat insulating member 721 is formed of, for example, resin, and suppresses heat conduction between the back cooling portion 71 and the force applying portion 72. It should be noted that the force applying portion 72 may also be in direct contact with the back cooling portion 71 without being interposed with the heat insulating member 721 or the like.

[0092] exist Figures 3 to 5 In the example shown, the shape of the force applying portion 72 when viewed from above is a roughly rectangular shape in which the length in the Y direction is longer than the length in the X direction. In other words, the shape of the force applying portion 72 when viewed from above is a roughly rectangular shape having a pair of long sides roughly parallel to the Y direction and a pair of short sides roughly parallel to the X direction. When viewed from above, the pair of long sides of the force applying portion 72 are roughly orthogonal to the pair of long sides of the back cooling portion 71. The end of the force applying portion 72 on the (+Y) side protrudes from the back cooling portion 71 to the (+Y) side when viewed from above, and the end of the force applying portion 72 on the (-Y) side protrudes from the back cooling portion 71 to the (-Y) side when viewed from above. In other words, both ends of the force applying portion 72 in the Y direction extend from the back cooling portion 71 to the Y direction when viewed from above.

[0093] The two ends of the force-applying portion 72 in the Y direction (i.e., the two ends in the direction parallel to the pair of long sides of the force-applying portion 72) are indirectly connected to the support substrate 60 via an intermediate member 722 mounted on the upper surface of the support substrate 60 by screw fixing or the like. Specifically, the two ends of the force-applying portion 72 in the Y direction are screwed (i.e., fastened using two screws 723) to the intermediate member 722 on the (+Y) side and (-Y) side of the back cooling portion 71, whereby the force-applying portion 72 is connected to the intermediate member 722 and indirectly connected to the support substrate 60 via the intermediate member 722. Thus, a downward force is applied from the force-applying portion 72 to the back cooling portion 71 via the heat insulating member 721, and the back cooling portion 71 is forced toward the main surface 612 on the (+Z) side of the DMD base portion 61. Thus, the temperature rise of the DMD base portion 61 is appropriately suppressed. In other words, the cooling of the DMD 6 from the DMD base portion 61 side by the back cooling portion 71 is appropriately achieved.

[0094] Each screw 723 is screwed into the screw hole of the intermediate member 722 when inserted into the coil spring 724, and the coil spring 724 is compressed between the screw head of the screw 723 and the intermediate member 722. As a result, the downward force acting on the back cooling unit 71 from the force-applying unit 72 is equalized in the Y direction. As a result, the force applied by the back cooling unit 71 to the main surface 612 on the (+Z) side of the DMD base unit 61 is equalized in the contact area between the back cooling unit 71 and the main surface 612, and the back cooling unit 71 is properly in contact with the DMD base unit 61. Therefore, the cooling of the DMD6 from the DMD base unit 61 side based on the back cooling unit 71 is better achieved.

[0095] It should be noted that the force (hereinafter also referred to as "back force") that applies the back cooling unit 71 to the main surface 612 on the (+Z) side of the DMD base unit 61 is set to an upper limit value based on the relationship with the structure of the DMD 6. The coil spring 724 is selected so that the back force does not exceed the upper limit value. In addition, the thermal conductivity and thickness of the heat transfer member 711 are set so that a sufficient heat transfer effect (i.e., heat dissipation effect) can be obtained under the back force.

[0096] exist Figure 3 and Figure 4 In the example shown, the intermediate member 722 is a member protruding from the upper surface of the support substrate 60 to the (+Z) side (i.e., the side where the back cooling unit 71 is arranged). The intermediate member 722 has a first member 725 and a second member 726. The second member 726 of the intermediate member 722 is a roughly flat member that is roughly perpendicular to the Z direction and is fixed to the upper surface of the support substrate 60. The shape of the second member 726 when viewed from above is a roughly rectangular frame with a through hole in the center. The above-mentioned lower end portion of the back cooling unit 71 is inserted into the through hole of the second member 726. As a result, the deviation of the relative position of the back cooling unit 71 with respect to the support substrate 60 is suppressed. The lower end portion of the back cooling unit 71 contacts the main surface 612 on the (+Z) side of the DMD base unit 61 via the through hole of the second member 726.

[0097] The first member 725 of the intermediate member 722 is fixed to the upper surface of the second member 726 (i.e., the main surface on the (+Z) side opposite to the support substrate 60). The first member 725 is an annular member in which a substantially flat plate-like portion is bent and continuous in an annular shape. The first member 725 is an integral member having a pair of support portions 727 and a pair of coupling portions 728.

[0098] A pair of support portions 727 are arranged on the (+Y) side and the (-Y) side of the back cooling portion 71. Each support portion 727 is a door-shaped portion that opens toward the (-Z) side (i.e., toward the second member 726 and the support substrate 60). The shape of each support portion 727 can be considered to be a roughly "U" shape that opens toward the (-Z) side. Each support portion 727 protrudes from the upper surface of the second member 726 toward the (+Z) side (i.e., the side opposite to the support substrate 60). Each support portion 727 can be considered to be a protrusion that protrudes from the support substrate 60 toward the (+Z) side. The shape of each support portion 727 when viewed from above is a roughly rectangular strip extending roughly parallel to the X direction. The size of each support portion 727 in the X direction is smaller than the size of the back cooling portion 71 in the X direction.

[0099] The pair of coupling parts 728 are approximately flat plate-shaped parts approximately perpendicular to the Z direction, and couple the lower ends of the pair of support parts 727 to each other at both ends of the pair of support parts 727 in the X direction. The shape of each coupling part 728 when viewed from above is a substantially rectangular band extending approximately parallel to the Y direction. Each coupling part 728 is directly in contact with the upper surface of the second member 726 and is fixed. For example, each coupling part 728 is fixed to the support substrate 60 by screwing or the like, with the second member 726 sandwiched between the coupling part 728 and the support substrate 60.

[0100] The upper end 727a of each support portion 727 (i.e., the end on the (+Z) side) is a substantially flat plate-shaped portion substantially perpendicular to the Z direction. The end of the force-applying portion 72 in the Y direction is connected to the center of the upper end 727a of each support portion 727 in the X direction by the screw 723. The portion of the upper end 727a of each support portion 727 to which the force-applying portion 72 is connected is located above the upper end of the back cooling portion 71 in the vertical direction (i.e., located on the opposite side of the DMD 6 across the back cooling portion 71 in the vertical direction).

[0101] In each support portion 727, a pair of legs 727b extending downward from both ends of the upper end portion 727a in the X direction is a roughly flat plate-shaped portion that is roughly perpendicular to the X direction. The lower end of each leg 727b is continuous with the above-mentioned connecting portion 728. In the support portion 727 on the (-Y) side of the pair of support portions 727, the pair of legs 727b is opposite to the side surface of the back cooling portion 71 on the (-Y) side in the Y direction, and is arranged close to or abutting the side surface. In the support portion 727 on the (+Y) side of the pair of support portions 727, the pair of legs 727b is opposite to the side surface of the back cooling portion 71 on the (+Y) side in the Y direction, and is arranged close to or abutting the side surface. That is, the pair of legs 727b of each support portion 727 extends in the up-down direction along the side surface of the back cooling portion 71 in the Y direction.

[0102] The back cooling portion 71 is supported by a pair of support portions 727 sandwiched in the Y direction. Specifically, the back cooling portion 71 is supported from the Y direction by a pair of legs 727b of each support portion 727. As described above, the back cooling portion 71 is a roughly rectangular parallelepiped shape that is long in the X direction and short in the Y direction. Therefore, it is relatively easy to tip over in the Y direction without being supported by other components. In the drawing device 1, the back cooling portion 71 is supported from the (+Y) side and the (-Y) side by a pair of support portions 727, thereby suppressing the back cooling portion 71 from tilting in the Y direction and preventing it from tipping over in the Y direction. In addition, when the force applying portion 72 is screwed to the intermediate member 722, the tilting of the back cooling portion 71 caused by the tightening order of the screws 723, etc. is suppressed.

[0103] It should be noted that the shapes and structures of the intermediate member 722 and the force applying portion 72 may be changed in various ways. For example, the first member 725 and the second member 726 of the intermediate member 722 may be an integral member. Alternatively, the first member 725 of the intermediate member 722 may not necessarily be an integral member, but may be divided into a plurality of members. In addition, the force applying portion 72 may be directly connected to the support substrate 60 without passing through the intermediate member 722 or the like.

[0104] The storage member 8 is a cylindrical (i.e., box-shaped) member with a cover that opens downward. Figure 4 In the example shown, the outer shape of the containing member 8 is roughly rectangular, and has a top cover portion 81 and a side wall portion 82. The top cover portion 81 of the containing member 8 is a roughly flat plate-shaped portion extending roughly perpendicularly to the Z direction. The side wall portion 82 of the containing member 8 is a roughly flat plate-shaped portion extending downward from the outer peripheral edge of the top cover portion 81 throughout the entire circumference. The containing member 8 covers the back cooling portion 71, the force applying portion 72, the intermediate member 722, etc., and is installed on the upper surface of the supporting substrate 60. Thus, the back cooling portion 71, the force applying portion 72, the intermediate member 722, etc. are contained in the internal space 80 of the containing member 8. It should be noted that the outer shape of the containing member 8 is not necessarily limited to a roughly rectangular shape, and may also be other shapes (for example, roughly cylindrical, roughly polygonal, or dome-shaped, etc.).

[0105] An air supply port 83 connected to a pipe extending from a dry gas supply source (not shown) is provided in the side wall portion 82 of the container member 8. In the internal space 80 of the container member 8, a dry gas having a lower dew point than the ambient gas around the container member 8 (i.e., the space outside the container member 8) is supplied through the air supply port 83. Thus, condensation on the surface of the back cooling portion 71 and the like is suppressed, and moisture is suppressed from adhering to the DMD 6. The dry gas supplied to the internal space 80 of the container member 8 is discharged to the outside of the container member 8 through an exhaust port 84 provided separately from the air supply port 83 in the side wall portion 82 of the container member 8. The above-mentioned dry gas is, for example, CDA (clean dry air). The dry gas may also be, for example, an inert gas such as nitrogen (N2).

[0106] The front cooling unit 74 includes a first nozzle 741 and a second nozzle 742. The first nozzle 741 and the second nozzle 742 are connected to a gas supply source (not shown) and supply gas to the DMD cover 63, thereby suppressing the temperature rise of the DMD cover 63 and the DMD reflector unit 62. The gas is, for example, compressed air or the above-mentioned dry gas. When the dry gas is supplied to the DMD cover 63, the first nozzle 741 and the second nozzle 742 may also be connected to the same dry gas supply source as the above-mentioned gas supply port 83.

[0107] The first nozzle 741 and the second nozzle 742 are disposed inside the support substrate 60, and the top end of each nozzle protrudes from the inner circumferential surface 602 of the through hole 601 of the support substrate 60 toward the space inside the through hole 601 (i.e., the space surrounded by the inner circumferential surface 602 of the through hole 601). The nozzle 743 of the first nozzle 741 (hereinafter, also referred to as the "first nozzle 743") is disposed on the inner circumferential surface 602 of the through hole 601 at a position closer to the (-Y) side than the DMD cover part 63 and the DMD reflector part 62. The nozzle 744 of the second nozzle 742 (hereinafter, also referred to as the "second nozzle 744") is disposed on the inner circumferential surface 602 of the through hole 601 at a position closer to the (+Y) side than the DMD cover part 63 and the DMD reflector part 62. Figure 5 In the example shown, the first jet port 743 is arranged near the end of the through hole 601 on the (-Y) side, and the second jet port 744 is arranged near the end of the through hole 601 on the (+Y) side. In other words, the first jet port 743 and the second jet port 744 are substantially opposite to each other in the Y direction across the DMD cover portion 63 and the DMD reflector portion 62. The first jet port 743 and the second jet port 744 eject gas substantially in parallel in the Y direction.

[0108] The flow of the gas ejected from the first nozzle 743 (hereinafter also referred to as the "first airflow") flows along the main surface 631 on the (-Z) side of the DMD cover 63 (i.e., the front face 631 of the DMD6) from the (-Y) side to the (+Y) side, approximately in parallel with the Y direction. The flow of the gas ejected from the second nozzle 744 (hereinafter also referred to as the "second airflow") flows along the main surface 631 on the (-Z) side of the DMD cover 63 from the (+Y) side to the (-Y) side, approximately in parallel with the Y direction. In the present embodiment, the first airflow and the second airflow flow approximately in parallel with the main surface 631 on the (-Z) side of the DMD cover 63. The temperatures of the first airflow and the second airflow are lower than the temperatures of the DMD cover 63 and the DMD reflector portion 62 of the DMD6 being driven, and therefore, the DMD cover 63 and the DMD reflector portion 62 are appropriately cooled. In addition, the first airflow and the second airflow are formed in the space inside the through hole 601 , and the gas is difficult to diffuse into the surrounding space, so the DMD cover part 63 and the DMD mirror part 62 are cooled better.

[0109] like Figure 2 As shown, the incident direction of the light entering the DMD6 from the illumination optical system 43 via the reflectors 471 and 472 is Figure 2 In other words, the incident direction is inclined toward the (-Y) direction relative to the Z direction (i.e., the thickness direction of the DMD base 61). In other words, the incident direction is substantially parallel to the YZ plane and is inclined relative to both the Y direction and the Z direction in the YZ plane.

[0110] Therefore, when the drawing device 1 draws the substrate 9, the amount of light irradiated to the DMD mirror unit 62 is uneven in the Y direction (hereinafter also referred to as "lateral"), and the temperature distribution of the DMD mirror unit 62 in the Y direction may be uneven. Figure 5 In the front cooling section 74 shown, as described above, the flow direction of the airflow (i.e., the first airflow and the second airflow) formed by the front cooling section 74 is roughly parallel to the Y direction, thereby being able to suppress the temperature difference of DMD6 in the Y direction caused by the above-mentioned uneven temperature distribution.

[0111] Figure 6 This is a bottom view of the portion near the DMD6 of the light modulating unit 44 as viewed from the (-Z) side. Figure 6As shown, the first nozzle 743 of the first nozzle 741 and the second nozzle 744 of the second nozzle 742 arranged around the through hole 601 of the support substrate 60 are at different positions in the X direction (i.e., the direction perpendicular to the above-mentioned lateral and thickness directions). Specifically, relative to the virtual straight line L1 passing through the center of the through hole 601 and extending along the Y direction when viewed from above, the first nozzle 743 deviates slightly to the (+X) side, and the second nozzle 744 deviates slightly to the (-X) side. As a result, the collision of the first airflow and the second airflow near the DMD cover part 63 (i.e., near the main surface 631 on the (-Z) side of the DMD cover part 63) is suppressed, and the cooling of the DMD cover part 63 and the DMD reflector part 62 can be properly achieved.

[0112] As shown above, the optical device 10 for irradiating modulated light to an object includes an illumination optical system 43, a light modulator 44, and a projection optical system 45. Light emitted from a light source 421 is incident on the illumination optical system 43. The light modulator 44 modulates the light guided by the illumination optical system 43. The projection optical system 45 guides the light modulated by the light modulator 44 to an object (the substrate 9 in the above example). The light modulator 44 includes a DMD 6, a support substrate 60, and a cooling unit 7. A through hole 601 on which the DMD 6 is mounted is provided on the support substrate 60. The cooling unit 7 cools the DMD 6. The DMD 6 includes a DMD base 61, a DMD reflector 62, and a DMD cover 63. The DMD reflector 62 includes a plurality of movable micro-mirrors arranged in a matrix on one side (the (-Z) side in the above example) in the thickness direction of the DMD base 61. The DMD cover 63 covers the DMD reflector 62 from one side in the thickness direction.

[0113] The cooling unit 7 includes a back cooling unit 71 and a force applying unit 72. The back cooling unit 71 contacts the main surface 612 on the other side (the (+Z) side in the above example) of the DMD base unit 61 in the thickness direction, and cools the DMD 6 by heat conduction. The force applying unit 72 contacts the back cooling unit 71 from the other side in the thickness direction. The force applying unit 72 is connected to the support substrate 60, thereby applying force to the back cooling unit 71 toward the main surface 612 on the other side (i.e., the back side 612 of the DMD 6) of the DMD base unit 61 in the thickness direction.

[0114] Thus, it is not necessary to provide the back cooling unit 71 with a flange or other structure for applying force to the back cooling unit 71 toward the DMD base unit 61, so that the structure of the back cooling unit 71 can be simplified and the DMD 6 can be cooled from the DMD base unit 61 side. As a result, the temperature of the back side 612 of the DMD 6 can be maintained within the range of the prescribed operating temperature condition, and the life of the DMD 6 can be suppressed from being shortened. Therefore, the replacement frequency of the DMD 6 in the optical device 10 can be reduced.

[0115] As described above, the force-applying portion 72 is indirectly connected to the support substrate 60 by being connected to the intermediate member 722 protruding from the support substrate 60 to the other side in the thickness direction. The portion where the force-applying portion 72 and the intermediate member 722 are connected is preferably closer to the other side (the (+Z) side in the above example) than the end of the other side of the back cooling portion 71 in the thickness direction. Thus, an operator who replaces the DMD 6 can easily approach the connection between the force-applying portion 72 and the intermediate member 722. Therefore, the force-applying portion 72 can be easily loaded and unloaded relative to the support substrate 60, and the replacement operation of the DMD 6 can be simplified.

[0116] As described above, the force applying portion 72 is indirectly connected to the support substrate 60 by being connected to the intermediate member 722 protruding from the support substrate 60 to the other side in the thickness direction. The intermediate member 722 preferably has a pair of support portions 727 that extend along the side of the back cooling portion 71 in the thickness direction (Z direction in the above example) and support the back cooling portion 71 by sandwiching it. In addition, the force applying portion 72 is preferably connected to the end of the pair of support portions 727 on the other side in the thickness direction (the (+Z) side in the above example). As described above, the back cooling portion 71 can be suppressed from tilting.

[0117] As described above, the force-applying portion 72 is indirectly connected to the support substrate 60 by being connected to the intermediate member 722 protruding from the support substrate 60 to the other side in the thickness direction. The intermediate member 722 preferably has a door-shaped protrusion (the support portion 727 in the above example) that protrudes from the support substrate 60 to the other side in the thickness direction and opens toward the support substrate 60. In addition, the force-applying portion 72 is preferably connected to the end of the other side in the thickness direction of the protrusion (the (+Z) side in the above example). Thus, when the force-applying portion 72 applies force to the back cooling portion 71, the protrusion is elastically deformed in the Z direction, and the force-applying portion 72 can appropriately apply force to the back cooling portion 71. As a result, the back cooling portion 71 can be appropriately force-applied to the DMD base portion 61.

[0118] As described above, the shapes of the back cooling portion 71 and the force applying portion 72 when viewed from above in parallel with the thickness direction (Z direction in the above example) are rectangular. Preferably, a pair of long sides of the force applying portion 72 are orthogonal to a pair of long sides of the back cooling portion 71 when viewed from above. In addition, preferably, both ends of the force applying portion 72 in a direction parallel to the pair of long sides of the force applying portion 72 (Y direction in the above example) are connected to the support substrate 60. Thus, it is possible to appropriately apply force to the back cooling portion 71 from the force applying portion 72. As a result, it is possible to appropriately apply force to the back cooling portion 71 toward the DMD base portion 61.

[0119] As described above, the light modulation unit 44 preferably further includes a covered cylindrical container member 8. The container member 8 is arranged on the other side of the support substrate 60 in the thickness direction (in the above example, the (+Z) side). The container member 8 covers the back cooling unit 71 and contains it in the internal space 80. Preferably, dry gas is supplied to the internal space 80 of the container member 8. Thus, condensation in the back cooling unit 71 can be suppressed.

[0120] As described above, the cooling unit 7 preferably further includes a front cooling unit 74, which forms an airflow along the main surface 631 on one side (the (-Z) side in the above example) of the thickness direction of the DMD cover 63 to cool the DMD 6. Thus, the DMD 6 can also be cooled from the DMD cover 63 side (i.e., the front 631 side of the DMD 6). As a result, the temperature of the front 631 side of the DMD 6 can be maintained within the range of the prescribed operating temperature conditions, and the temperature difference between the front 631 side and the back 612 side of the DMD 6 can also be maintained within the range of the prescribed operating temperature conditions. Therefore, the life of the DMD 6 can be suppressed from being further shortened, and the replacement frequency of the DMD 6 in the optical device 10 can be further reduced.

[0121] As described above, the flow direction of the airflow formed by the front cooling unit 74 is preferably parallel to the main surface 631 on one side (the (-Z) side in the above example) in the thickness direction of the DMD cover 63. As a result, the stagnation of the ambient gas near the main surface 631 of the DMD cover 63 can be appropriately suppressed, and as a result, the DMD 6 can be appropriately cooled.

[0122] As described above, the incident direction of light to DMD6 is inclined in a lateral direction (in the above example, Y direction) perpendicular to the thickness direction (in the above example, Z direction) relative to the thickness direction. Moreover, the flow direction of the airflow formed by the front cooling unit 74 is preferably parallel to the lateral direction. Thus, as described above, the lateral temperature difference in DMD6 can be suppressed.

[0123] As described above, the airflow formed by the front cooling unit 74 preferably includes: a first airflow flowing from one side to the other side in the lateral direction perpendicular to the thickness direction (in the above example, from the (-Y) side to the (+Y) side); and a second airflow flowing from the other side to one side in the lateral direction (in the above example, from the (+Y) side to the (-Y) side). Thus, the gas from the front cooling unit 74 can be uniformly supplied to substantially the entire main surface 631 on the (-Z) side of the DMD cover 63. As a result, the lateral temperature difference in the DMD 6 can be further suppressed.

[0124] As described above, it is preferred that the positions of the first jet outlet 743 for forming the first airflow and the second jet outlet 744 for forming the second airflow are different from each other in the direction perpendicular to the thickness direction and the lateral direction (in the above example, the X direction). Thus, the collision of the first airflow and the second airflow near the DMD cover 63 can be suppressed, and therefore, cooling can be appropriately performed from the front face 631 side of the DMD 6.

[0125] The above-mentioned drawing device 1 irradiates light onto the substrate 9 to draw a pattern. The drawing device 1 has: a stage 21, the above-mentioned optical device 10, and a scanning mechanism (the stage moving mechanism 22 in the above-mentioned example). The stage 21 holds the substrate 9. The optical device 10 irradiates modulated light onto the substrate 9. The scanning mechanism moves the stage 21 relative to the optical device 10 in a scanning direction (the Y direction in the above-mentioned example) parallel to the main surface (i.e., the upper surface 91) of the substrate 9. As described above, in the optical device 10, the structure of the back cooling unit 71 can be simplified and the DMD 6 can be cooled, so the replacement frequency of the DMD 6 can be reduced. Therefore, the structure of the drawing device 1 can be simplified, and the maintenance frequency of the drawing device 1 related to the optical device 10 can also be reduced.

[0126] Various modifications can be made to the above-described optical device 10 and image drawing device 1 .

[0127] For example, in the front cooling section 74, the flow direction of the first airflow and / or the second airflow is not necessarily parallel to the main surface 631 on the (-Z) side of the DMD cover section 63. For example, gas may be ejected obliquely upward toward the main surface 631 from the first nozzle 743 and / or the second nozzle 744 arranged obliquely below the main surface 631 on the (-Z) side of the DMD cover section 63.

[0128] In the front cooling unit 74, the positions of the first and second ejection ports 743 and 744 are not limited to the above-mentioned examples, and various changes can be made. For example, the first and second ejection ports 743 and 744 can also be arranged on the above-mentioned virtual straight line L1 (see Figure 6 ). In addition, for example, the first ejection port 743 may be arranged near the end of the through hole 601 on the (+X) side, and the second ejection port 744 may be arranged near the end of the through hole 601 on the (-X) side.

[0129] In addition, in the front cooling unit 74, one of the first and second ejection ports 743 and 744 may be omitted. Alternatively, in addition to the first and second ejection ports 743 and 744, another ejection port may be provided.

[0130] In the above-mentioned cooling unit 7, the shape and structure of the force-applying portion 72 and the intermediate member 722, as well as the connection position and connection structure of the force-applying portion 72 relative to the intermediate member 722, are not limited to the above-mentioned examples, and various changes can be made. For example, the support portion 727 of the intermediate member 722 is not necessarily a door-shaped, for example, it can also be a roughly flat plate extending roughly perpendicular to the Y direction. In addition, the connection portion between the intermediate member 722 and the force-applying portion 72 can also be located at the same position as the upper end of the back cooling unit 71 or at a position lower than the upper end (i.e., the (-Z) side).

[0131] In the intermediate member 722, the pair of support portions 727 for supporting the back cooling portion 71 from the side may not necessarily be provided. For example, a pair of protrusions separated from the back cooling portion 71 in the Y direction may be provided, and both ends of the force applying portion 72 in the Y direction are connected to the pair of protrusions. Alternatively, the pair of support portions 727 for supporting the back cooling portion 71 from the side may be provided independently of the pair of protrusions to which the force applying portion 72 is connected.

[0132] The shape of the force applying part 72 may be, for example, a substantially rectangular parallelepiped. In addition, in the cooling part 7, the intermediate member 722 may not be provided, but the two lower ends of the force applying part 72 of the substantially gate shape (i.e., substantially U-shaped) across the back cooling part 71 may be directly connected to the support substrate 60.

[0133] In the above-mentioned cooling unit 7, a water-cooling jacket having a substantially rectangular parallelepiped shape is used as the back cooling unit 71, but the shape, structure, type, etc. of the back cooling unit 71 can be changed in various ways. For example, the shape of the back cooling unit 71 can be substantially cylindrical, substantially polygonal, or substantially flat. The positions of the inlet and outlet of the refrigerant relative to the flow path 710 of the back cooling unit 71 can also be changed in various ways. Alternatively, the cooling of the DMD 6 from the DMD base unit 61 side does not necessarily require the use of the refrigerant flowing through the flow path 710 of the back cooling unit 71, and can also be performed using other structures such as a Peltier element.

[0134] Figure 7It is a side view showing the structure of the optical modulation section 44a provided with a Peltier element as a back cooling section 71a. In the optical modulation section 44a, the heat absorbing surface, i.e., the lower surface, of the back cooling section 71a, which is a Peltier element, is indirectly in contact with the main surface 612 on the (+Z) side of the DMD base section 61 of the DMD6 supported by the supporting substrate 60 (i.e., the back side 612 of the DMD6) via the heat transfer member 711a. In addition, a force-applying section 72a, which is roughly flat in shape, is in contact with the upper surface (i.e., the main surface on the (+Z) side) of the back cooling section 71a from the upper side. The force-applying section 72a is connected to the supporting substrate 60 by a screw 723, thereby applying force to the back cooling section 71a toward the main surface 612 on the (+Z) side of the DMD base section 61. Thus, the structure of the back cooling section 71a can be simplified, and the DMD6 can be cooled from the DMD base section 61 side.

[0135] In the light modulation unit 44a, a water cooling jacket 75 is provided above the force applying unit 72a. The water cooling jacket 75 contacts the upper surface of the force applying unit 72a from the upper side, and cools the upper surface of the back cooling unit 71a, which is the heat generating surface, through the force applying unit 72a. Thus, the DMD 6 can be properly cooled by the back cooling unit 71a.

[0136] In the light modulation section 44a, similarly to the light modulation section 44, the container member 8 is mounted on the upper surface of the support substrate 60. The back cooling section 71a, the force applying section 72a, the water cooling jacket 75, etc. are accommodated in the internal space 80 of the container member 8. The dry gas is supplied to the internal space 80 of the container member 8. Thus, condensation on the surfaces of the back cooling section 71a, the water cooling jacket 75, etc. is suppressed.

[0137] It should be noted that in the light modulation unit 44a, the dry gas may not necessarily be supplied to the internal space 80 of the storage member 8. In this case, the storage member 8 may be omitted from the light modulation unit 44a. The same applies to the light modulation unit 44.

[0138] In the optical device 10 , the front cooling unit 74 may be omitted.

[0139] In the drawing device 1, the stage 21 only needs to be moved in the main scanning direction relative to the drawing head 41 by the first moving mechanism 23. Therefore, for example, the stage 21 may be fixed, and the drawing head 41 may be moved in the main scanning direction by the first moving mechanism 23 above the stage 21. Similarly, the drawing head 41 may be moved in the sub-scanning direction by the second moving mechanism 24.

[0140] The substrate 9 is not necessarily limited to a printed substrate. In the drawing device 1, for example, patterns can be drawn on semiconductor substrates, semiconductor packaging substrates, glass substrates for flat panel displays such as liquid crystal display devices or plasma display devices, glass substrates for photomasks, and substrates for solar cell panels.

[0141] The optical device 10 may be used as a device for irradiating modulated light onto the substrate 9 in a drawing device having a different structure from the drawing device 1. Alternatively, the optical device 10 may be used as a device other than a drawing device for irradiating modulated light onto an object.

[0142] The above-mentioned embodiments and the structures in the various modifications can be appropriately combined as long as they do not contradict each other.

[0143] Although the invention has been described in detail, the above description is illustrative and not restrictive, and therefore, it can be understood that many modifications and aspects can be made without departing from the scope of the invention.

Claims

1. An optical device for irradiating a modulated light onto an object, wherein: have: an illumination optical system into which light emitted from a light source is incident; a light modulation unit that modulates the light guided by the illumination optical system; as well as a projection optical system that guides the light modulated by the light modulating unit toward an object; The light modulation unit has: Digital micromirror device; a supporting substrate provided with a through hole on which the digital micromirror device is mounted; and A cooling unit, for cooling the digital micromirror device; The digital micromirror device has: A digital micromirror device base portion; A digital micromirror device reflector portion, comprising a plurality of movable micromirrors arranged in a matrix on one side in the thickness direction of the digital micromirror device base portion; as well as A digital micromirror device cover portion, covering the digital micromirror device reflector portion from the one side in the thickness direction; The cooling unit has: A back cooling portion, in contact with the main surface of the other side of the thickness direction of the digital micromirror device base portion, and cooling the digital micromirror device by heat conduction; as well as The force applying portion contacts the back surface cooling portion from the other side in the thickness direction and is connected to the support substrate, thereby applying force to the back surface cooling portion toward the main surface of the DMD base portion on the other side in the thickness direction.

2. The optical device according to claim 1, wherein: The force applying portion is indirectly connected to the support substrate by being connected to an intermediate member protruding from the support substrate toward the other side in the thickness direction. A portion where the biasing portion and the intermediate member are connected is located closer to the other side than the other end portion of the back surface cooling portion in the thickness direction.

3. The optical device according to claim 1, wherein: The force applying portion is indirectly connected to the support substrate by being connected to an intermediate member protruding from the support substrate toward the other side in the thickness direction. The intermediate member has a pair of support portions, the pair of support portions extending along the side surfaces of the back cooling portion in the thickness direction and supporting the back cooling portion by sandwiching the back cooling portion; The biasing portion is connected to the other end portions of the pair of support portions in the thickness direction.

4. The optical device according to claim 1, wherein: The force applying portion is indirectly connected to the support substrate by being connected to an intermediate member protruding from the support substrate toward the other side in the thickness direction. The intermediate member has a gate-shaped protrusion, the protrusion protruding from the support substrate toward the other side in the thickness direction and opening toward the support substrate, The biasing portion is connected to the other end portion of the protruding portion in the thickness direction.

5. The optical device according to claim 1, wherein: The back cooling portion and the force applying portion each have a rectangular shape when viewed from above in parallel with the thickness direction. The pair of long sides of the force applying portion and the pair of long sides of the back cooling portion are orthogonal to each other in a plan view. Both ends of the urging portion in a direction parallel to the pair of long sides of the urging portion are connected to the support substrate.

6. The optical device according to claim 1, wherein: The light modulator further includes a covered cylindrical housing member, which is arranged on the other side of the support substrate in the thickness direction, covers the back cooling unit and houses the back cooling unit in an internal space, and a dry gas is supplied to the internal space.

7. The optical device according to claim 1, wherein: The cooling unit further includes a front cooling unit that forms an airflow along the main surface on the one side in the thickness direction of the digital micromirror device cover to cool the digital micromirror device.

8. The optical device according to claim 7, wherein: The flow direction of the airflow formed by the front cooling portion is parallel to the main surface on the one side in the thickness direction of the DMD cover portion.

9. The optical device according to claim 7, wherein: The incident direction of light on the digital micromirror device is inclined in a lateral direction perpendicular to the thickness direction relative to the thickness direction. The flow direction of the airflow formed by the front cooling portion is parallel to the lateral direction.

10. The optical device according to claim 7, wherein: The airflow formed by the front cooling section includes: A first airflow flows from one side to the other side in a lateral direction perpendicular to the thickness direction; and The second airflow flows from the other side in the lateral direction to the one side.

11. The optical device according to claim 10, wherein: In a direction perpendicular to the thickness direction and the lateral direction, a position of a first ejection port forming the first airflow and a position of a second ejection port forming the second airflow are different from each other.

12. A drawing device for drawing a pattern by irradiating light onto a substrate, wherein: have: a stage, holding the substrate; The optical device according to any one of claims 1 to 11, wherein the substrate is irradiated with modulated light; and The scanning mechanism moves the stage relative to the optical device in a scanning direction parallel to the main surface of the substrate.

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