Light detection device and light irradiation device

Abstract

To provide a technique for suppressing lowering of light detection accuracy by suppressing decrease in a light quantity caused by propagation.SOLUTION: A light detection device for detecting light irradiated from a light irradiation part includes: a propagation member for propagating light irradiated from the light irradiation part; and a light detector for detecting the light propagated by the propagation member, wherein a plurality of first scattering parts for scattering the light are discretely provided on the propagation member.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The technology disclosed in the present specification relates to a technology for detecting irradiated light. [Background technology]

[0002] 2. Description of the Related Art Optical processing techniques have been used in the past to process objects by irradiating them with light such as laser light (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2006-272430 A Summary of the Invention [Problem to be solved by the invention]

[0004] When the irradiated light is detected through a propagation member as described above, the amount of detected light may be significantly reduced due to diffusion during the propagation process. In such cases, the accuracy of light detection may be reduced due to the lack of light amount.

[0005] The technology disclosed in this specification has been made in consideration of the problems described above, and is a technology for suppressing the decrease in light quantity caused by propagation, thereby suppressing the deterioration of light detection accuracy. [Means for solving the problem]

[0006] A first aspect of the technology disclosed in the present specification is a light detection device that detects light irradiated from a light irradiation unit, and includes a propagation member for propagating the light irradiated from the light irradiation unit, and a light detector for detecting the light propagated by the propagation member, and the propagation member is provided with a plurality of first scattering units for scattering the light. The light source further includes a stage, the light irradiation unit irradiates the light onto an upper surface of the stage, and at least one fourth scattering unit for scattering the light is provided on at least a part of the stage, the fourth scattering unit being made of a transparent material, and the propagation member propagates the light incident via the fourth scattering unit. .

[0007] A second aspect of the technology disclosed in the present specification is related to the first aspect of the photodetection device, in which the photodetector is positioned opposite a longitudinal end of the propagation member, and the multiple first scattering sections are discretely arranged along the longitudinal direction of the propagation member.

[0008] A photodetection device which is a third aspect of the technology disclosed in the present specification is related to the photodetection device which is the first or second aspect, wherein the propagation member has an end portion facing the photodetector, and the width of a second scattering portion which is one of the plurality of first scattering portions is greater than or equal to the width of a third scattering portion which is a scattering portion located at a position closer to the end portion than the second scattering portion.

[0010] The first aspect of the technology disclosed in this specification 4 The photodetector according to the present embodiment is 3 In the photodetector according to the aspect of the present invention, each of the first scattering portions is disposed in a position corresponding to a position of the fourth scattering portion.

[0011] The first aspect of the technology disclosed in this specification 5 The photodetector according to the present embodiment is 3 or 4 The optical detection device according to the embodiment further includes a focusing lens for focusing the light incident through the fourth scattering section, and a light-shielding plate arranged at a position farther from the fourth scattering section than the focusing lens and at the focusing position of the focusing lens, and the propagation member propagates the light focused by the focusing lens.

[0012] The first aspect of the technology disclosed in this specification 6 The photodetector according to the embodiment includes first to 5 In the optical detection device according to any one of the above aspects, the plurality of first scattering portions are formed by blasting a surface of the propagation member.

[0013] The first aspect of the technology disclosed in this specification 7 The photodetector according to the embodiment includes first to 5In the photodetector according to any one of the above aspects, the first scattering portions are reflective films applied to a lower surface of the propagation member.

[0014] The first aspect of the technology disclosed in this specification 8 The photodetector according to the embodiment includes first to 7 In the light detection device according to any one of the above aspects, the light irradiated from the light irradiating section is laser light.

[0015] The first aspect of the technology disclosed in this specification 9 The photodetector according to the embodiment includes first to 8 The present invention relates to an optical detection device that is any one of the above aspects, further comprising a chamber in which the propagation member is contained, and the optical detector detects the light propagated by the propagation member outside the chamber.

[0016] The first aspect of the technology disclosed in this specification 10 The light irradiation device according to the embodiment includes at least one light irradiation unit for irradiating light, and first to second light irradiation units. 9 and a light detection device according to any one of the above aspects. Effect of the Invention

[0017] According to at least the first aspect of the technology disclosed in the present specification, it is possible to suppress a decrease in the amount of propagated light by suppressing excessive diffusion of the light while it is propagating through the propagation member, and as a result, it is possible to suppress a decrease in the light detection accuracy.

[0018] Furthermore, objects, features, aspects and advantages associated with the technology disclosed herein will become more apparent from the detailed description set forth below and the accompanying drawings. [Brief description of the drawings]

[0019] [Figure 1] FIG. 1 is a perspective view illustrating an example of the configuration of a light irradiation device according to an embodiment. [Diagram 2]2 is a cross-sectional view showing an example of the internal configuration and peripheral configuration of a vacuum chamber of a light irradiation device according to an embodiment. [Diagram 3] FIG. 3 is a perspective view mainly showing a light irradiation unit and a stage in the configuration exemplified in FIG. 2. [Figure 4] 3 is a cross-sectional view mainly showing an example of the configuration of a light irradiation unit and a stage from the configuration shown in FIG. 2. FIG. [Diagram 5] 11A and 11B are diagrams illustrating examples of the width of the scattering portion. [Figure 6] 11A and 11B are diagrams illustrating examples of the width of the scattering portion. [Figure 7] FIG. 4 is a schematic diagram showing a light collecting unit and a transparent rod in a detection section. [Figure 8] FIG. 4 is a schematic diagram showing a light collecting unit and a transparent rod in a detection section. [Figure 9] FIG. 1 is a diagram showing how light propagates in a transparent rod. [Figure 10] FIG. 1 is a diagram showing how light propagates in a transparent rod. [Figure 11] 1 is a cross-sectional view showing a schematic example of the configuration of a transparent rod. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Hereinafter, the embodiments will be described with reference to the accompanying drawings. In the following embodiments, detailed features are shown for the purpose of explaining the technology, but they are merely examples and are not necessarily all essential features for enabling the embodiments to be implemented.

[0021] The drawings are schematic, and for the convenience of explanation, the configuration may be omitted or simplified as appropriate. The size and positional relationship of the configurations shown in different drawings are not necessarily described accurately, and may be changed as appropriate. Hatching may be added to drawings such as plan views that are not cross-sectional views, in order to make it easier to understand the contents of the embodiment.

[0022] In the following description, the same components are denoted by the same reference numerals, and their names and functions are also the same. Therefore, detailed descriptions thereof may be omitted to avoid duplication.

[0023] Furthermore, in the description in this specification, when a certain component is described as "comprising," "including," or "having," unless otherwise specified, this is not an exclusive expression that excludes the presence of other components.

[0024] Furthermore, even if ordinal numbers such as "first" or "second" are used in the description of this specification, these terms are used for convenience to facilitate understanding of the contents of the embodiments, and the contents of the embodiments are not limited to the orders that may result from these ordinal numbers.

[0025] In addition, in the description given in this specification, expressions such as "positive direction of the ... axis" or "negative direction of the ... axis" refer to the direction along the arrow of the ... axis shown in the figure as the positive direction, and the direction opposite to the arrow of the ... axis shown in the figure as the negative direction.

[0026] Furthermore, although the descriptions in this specification may use terms indicating specific positions or directions, such as "top," "bottom," "left," "right," "side," "bottom," "front," or "back," these terms are used for convenience to facilitate understanding of the contents of the embodiments, and do not relate to the positions or directions in which the embodiments are actually implemented.

[0027] In addition, in the description of the present specification, when "the upper surface of ..." or "the lower surface of ..." is stated, it is intended to include not only the upper surface or lower surface of the target component itself, but also a state in which another component is formed on the upper surface or lower surface of the target component. In other words, for example, when it is stated that "B is provided on the upper surface of A," it does not prevent another component "C" from being interposed between A and B.

[0028] Furthermore, in the explanations given in this specification, expressions indicating a shape, such as a "prism shape" or a "cylindrical shape", unless otherwise specified, include cases in which the shape is strictly that shape, and cases in which irregularities or chamfers are formed within a tolerance or within a range in which the same level of functionality is obtained.

[0029] <Embodiment Mode> The light detection device and the light irradiation device according to the present embodiment will be described below. Note that in the following embodiment, a light irradiation device in which the inside of the chamber is a vacuum or a reduced pressure atmosphere is described as an example, but the present invention can also be applied to a case in which the inside of the chamber is not a vacuum.

[0030] <Configuration of the light irradiation device> Fig. 1 is a perspective view showing a schematic example of the configuration of a light irradiation device 1 according to the present embodiment. In Fig. 1, a chamber frame supporting a vacuum chamber 12, wiring actually connected thereto, and the like are omitted for convenience. Note that, although the "vacuum" in the present embodiment is preferably a high vacuum (for example, 0.00001 Pa) to prevent deterioration of the characteristics of the substrate W, it also includes a vacuum level below the high vacuum.

[0031] As shown in FIG. 1, the light irradiation device 1 includes a vacuum chamber 12, an external fixed part 14 such as a stone surface plate, a bellows 16A which is an elastic member formed of, for example, stainless steel and connects the vacuum chamber 12 and the external fixed part 14, a light irradiation part 18 which irradiates light into the vacuum chamber 12, a vacuum pump 21 which reduces the pressure in the vacuum chamber 12 to create a vacuum state, and a control part 22 which controls each of the driving parts of the light irradiation device 1. In the above, a bellows made of stainless steel or the like is shown as an example of the elastic member, but an elastic member made of a metal other than stainless steel may be adopted, or an elastic member made of a resin or the like may be adopted depending on the required specifications. In addition, the shape of the elastic member does not have to be a bellows shape like the above bellows 16A.

[0032] The vacuum chamber 12 has a space therein for accommodating a substrate W. The substrate W to be processed includes, for example, a semiconductor wafer, a glass substrate for a liquid crystal display device, a substrate for a flat panel display (FPD) such as an organic electroluminescence (EL) display device, a substrate for an optical disk, a substrate for a magnetic disk, a substrate for a magneto-optical disk, a glass substrate for a photomask, a ceramic substrate, a substrate for a field emission display (i.e., FED), or a substrate for a solar cell. The substrate W is, for example, a substrate having a thin film formed on the upper surface.

[0033] An opening 12A is formed on the side surface of the vacuum chamber 12, through which the substrate W passes when the substrate W is loaded and unloaded. The opening 12A is appropriately closed when the vacuum chamber 12 is in a vacuum state. Other components accommodated inside the vacuum chamber 12 will be described later.

[0034] The light irradiation unit 18 irradiates light toward the upper surface of the substrate W accommodated in the vacuum chamber 12. At this time, the substrate W is aligned in advance by a detection unit or the like described later. The light irradiation unit 18 performs ablation processing of the substrate W by irradiating it with, for example, laser light. The light irradiation unit 18 may irradiate light such as an electron beam depending on the purpose of processing or the like. The light irradiation unit 18 irradiates light from outside the vacuum chamber 12 to the upper surface of the substrate W accommodated in the vacuum chamber 12 through an irradiation window (transparent plate made of quartz or the like) not shown. Then, the substrate W in the vacuum chamber 12 moves relative to the light irradiation unit 18, or the light scans the upper surface of the substrate W by controlling the optical system in the light irradiation unit 18. The light irradiation unit 18 is also disposed on the upper surface of a stand 24 fixed to the external fixed unit 14.

[0035] The control unit 22 may include a storage device including a memory (storage medium) including, for example, a hard disk drive (HDD), a random access memory (RAM), a read only memory (ROM), a flash memory, a volatile or non-volatile semiconductor memory, a magnetic disk, a flexible disk, an optical disk, a compact disk, a mini disk, or a DVD, a processing circuit such as a central processing unit (CPU) that executes a program stored in the storage device, an external CD-ROM, an external DVD-ROM, or an external flash memory, an input device capable of inputting information such as a mouse, a keyboard, a touch panel, or various switches, and an output device capable of outputting information such as a display, a liquid crystal display device, or a lamp.

[0036] The control unit 22 controls the output of the light source in the light irradiation unit 18 and the direction in which the light is irradiated, or controls the output of the vacuum pump 21, and further controls the driving of each driving unit described later.

[0037] 2 is a cross-sectional view showing an example of the internal configuration and peripheral configuration of the vacuum chamber 12 of the light irradiation device 1 according to the present embodiment. As shown in FIG. 2, the inside of the vacuum chamber 12 includes a stage 42 on the upper surface of which the substrate W is placed, a slider 44 that is movable in the Y-axis direction and supports the stage 42 from below, a base 46 that is fixed to the external fixed part 14 independently of the vacuum chamber 12, a linear guide 48 that is fixed to the base 46 and extends in the Y-axis direction, a linear motor mechanism 50 that moves the slider 44 along the linear guide 48 in the Y-axis direction, and a lift pin mechanism 52 having lift pins 52A that penetrate through holes (not shown here) formed in the stage 42 and support the substrate W.

[0038] The stage 42 holds the substrate W substantially horizontally with the processing surface of the substrate W facing upward. A detailed configuration of the stage 42 will be described later. A slider 44 supporting the stage 42 is moved in the Y-axis direction by a linear motor mechanism 50, and the light irradiated from the light irradiator 18 is scanned in the X-axis direction, so that the entire surface of the processing region of the substrate W can be scanned by the light in a planar view. Alternatively, the light irradiated from the light irradiator 18 is scanned in the X-axis and Y-axis directions, so that the entire surface of the processing region of the substrate W can be scanned by the light in a planar view. The lift pin mechanism 52 is fixed to the base 46.

[0039] The linear motor mechanism 50 is fixed to the external fixed part 14 located on the side of the vacuum chamber 12 through an opening 12B formed on the side of the vacuum chamber 12. Specifically, the linear motor mechanism 50 is fixed to the end of a hollow columnar member 14A passing through a bellows 16A welded to the opening 12B. At this time, wiring and the like connected to the linear motor mechanism 50 are led out to the outside of the vacuum chamber 12 through the inside of the columnar member 14A. The columnar member 14A included in the external fixed part 14 is fixed to an external member 14B included in the external fixed part 14. Moreover, the columnar member 14A does not come into contact with the bellows 16A connected to the side of the vacuum chamber 12.

[0040] The base 46 is fixed to the external fixed part 14 located below the vacuum chamber 12 through an opening 12C formed in the bottom surface of the vacuum chamber 12. Specifically, the base 46 is fixed to an end of a columnar member 14C passing through a bellows 16B welded to the opening 12C. The columnar member 14C included in the external fixed part 14 is fixed to an external member 14B included in the external fixed part 14. The columnar member 14C does not contact the bellows 16B connected to the bottom surface of the vacuum chamber 12.

[0041] 2, the external fixed parts 14 are disposed across the sides and below the vacuum chamber 12, but it is not essential that the external fixed parts 14 are continuous at these positions, and they may be provided dispersedly at these positions, or may be provided only at one of the positions. The vacuum chamber 12 is supported and fixed from below in the vertical direction by a chamber frame (not shown) separate from the bellows 16B, but the chamber frame is provided independently of the external fixed parts 14.

[0042] 3 is a perspective view mainly showing the light irradiation unit 18 and the stage 42 of the configuration exemplified in FIG. 2. FIG. 3 shows a state in which the substrate W is placed on the upper surface of the stage 42. The light irradiation unit 18 can scan the light irradiation direction in the X-axis direction in FIG. 3, and the stage 42 can move in the Y-axis direction by a linear motor mechanism 50 (see FIG. 2). Thus, the light irradiated from the light irradiation unit 18 to the upper surface of the stage 42 can form a rectangular irradiation area (light irradiation area) on the upper surface of the substrate W.

[0043] As shown in FIG. 3, the stage 42 has an object placement area 42A in which a substrate W, which is an object to be irradiated with light by the light irradiation unit 18, is placed, and a position calibration area 42B, which is an area for calibrating the position of the light irradiated by the light irradiation unit 18.

[0044] The object placement area 42A places the substrate W at a specific position within the object placement area 42A. This allows the positional relationship between the stage 42 and the substrate W to be specified in advance. In the position calibration area 42B, the position of light irradiated from the light irradiation unit 18 into the position calibration area 42B is detected. Then, in the position calibration area 42B, prior to optical processing of the substrate W in the object placement area 42A, the correspondence relationship between the setting value of the direction of light irradiated from the light irradiation unit 18 and the irradiation position of the detected light is calibrated.

[0045] A light-transmitting section 142 that transmits light is provided in at least a portion of the position calibration area 42B. The light-transmitting section 142 is made of a transparent material such as a glass material such as quartz (SiO2) or a transparent resin (for example, silicon resin). The light-transmitting section 142 is provided from the upper surface to the lower surface of the stage 42 corresponding to the position calibration area 42B. The light irradiated from the light irradiating section 18 to the light-transmitting section 142 is transmitted from the upper surface to the lower surface of the stage 42.

[0046] The light transmitting section 142 is provided with, for example, four scattering sections 142A. The number of scattering sections 142A is not limited to four. The scattering sections 142A are made of a transparent material, and reflect or transmit the irradiated light while scattering it. The positions at which the scattering sections 142A are provided are specific positions on the stage 42. That is, the positions of the scattering sections 142A on the entire stage 42 are specified in advance. In FIG. 3, each scattering section 142A is disposed at an end in the X-axis direction of the light irradiation area of ​​the light irradiation section 18, but the positions at which the scattering sections 142A are disposed may be specific positions on the stage 42 and are not limited to the ends of the light irradiation area of ​​the light irradiation section 18. The scattering sections 142A have a property of scattering incident light, and are obtained, for example, by performing blast processing on a glass material or performing frost processing using hydrofluoric acid or the like. In FIG. 3, each scattering portion 142A is formed on the upper surface of light transmitting portion 142, but at least one scattering portion 142A may be formed on the lower surface of light transmitting portion 142.

[0047] 3, the target placement area 42A and the position calibration area 42B are separate areas, but these areas may at least partially overlap. That is, the light-transmitting section 142 may be provided in at least a portion of the area where the substrate W is to be placed. In such a case, for example, in a state where the substrate W is not placed, calibration of the position of the light irradiated from the light irradiation section 18 may be performed at the position where the substrate W is to be placed.

[0048] Furthermore, scattering portion 142A may be formed over the entire range of light transmitting portion 142. In other words, there may be no portion through which light only passes, and light may be scattered over the entire range of light transmitting portion 142.

[0049] 3, the light-transmitting portion 142 is provided extending in the X-axis direction, and the scattering portion 142A is provided at each end in the X-axis direction, but the light-transmitting portion 142 may be divided into a plurality of portions in the X-axis direction. However, when a plurality of scattering portions 142A are provided in the integrally formed light-transmitting portion 142 (i.e., the case shown in FIG. 3), the light-transmitting portion 142 can be attached to the stage 42 (fitted in the case of FIG. 3) while maintaining the positional accuracy between the plurality of scattering portions 142A when the light-transmitting portion 142 is manufactured from a transparent material. Therefore, since no positional deviation occurs between the scattering portions 142A when the light-transmitting portion 142 is attached to the stage 42, the accuracy of the calibration performed using the plurality of scattering portions 142A can be maintained at a high level.

[0050] FIG. 4 is a cross-sectional view showing an example of the configuration of the light irradiation unit 18 and the stage 42 among the configurations shown in FIG. 2. As shown in FIG. 4, the light irradiation unit 18 includes a scanner 18A, which is a galvanometer mirror or a polygon mirror, for controlling the direction of the irradiated light in the X-axis direction and the Y-axis direction, and a condenser lens 18B for condensing light from a light source (not shown). In FIG. 4, the light irradiated through the condenser lens 18B and the irradiation window 20 formed of quartz or the like is, for example, a laser light 18C. The laser light 18C can scan the substrate W placed on the upper surface of the stage 42 in the X-axis direction and the Y-axis direction by controlling the scanner 18A. Here, it is preferable that the light irradiation unit 18 can control the light in the X-axis direction and the Y-axis direction, but the light irradiation unit 18 may be capable of controlling the light in either the X-axis direction or the Y-axis direction.

[0051] Stage 42 includes light-transmitting portion 142 formed in position calibration area 42B (see FIG. 3) and scattering portion 142A formed on the upper surface of light-transmitting portion 142. Laser light 18C irradiated from light irradiator 18 can scan a range in the X-axis direction that reaches at least scattering portion 142A.

[0052] A detector 62 for detecting light is disposed below the stage 42. The detector 62 includes a light collecting unit 62A that collects light in the vacuum chamber 12, a transparent rod 62D that propagates the light collected by the light collecting unit 62A, a plurality of scattering sections 166 that are provided in the transparent rod 62D at intervals in the X-axis direction, a fiber 62B that outputs the light propagating in the transparent rod 62D from the transparent rod 62D, a collecting lens 62E that collects the light output from the fiber 62B, and a photodetector 62C that detects the light collected by the collecting lens 62E outside the vacuum chamber 12 through a transparent window 20A provided in the housing of the vacuum chamber 12. By providing the transparent rod 62D and the photodetector 62C, a photodetector can be configured.

[0053] The multiple scattering sections 166 include scattering section 166A formed extending in the Y-axis direction, and scattering section 166B formed extending in the Y-axis direction longer than scattering section 166A. In Fig. 4, two scattering sections 166A are arranged in positions close to photodetector 62C, and two scattering sections 166B are arranged in positions far from photodetector 62C.

[0054] In Fig. 4, two scattering sections 166A are arranged in succession, and further, two scattering sections 166B are arranged in succession. That is, the width of the scattering section 166 in the Y-axis direction increases stepwise (discontinuously) from the side closer to the photodetector 62C. However, for example, four scattering sections 166 each having a different width in the Y-axis direction may be arranged in a direction away from the photodetector 62C, and the widths in the Y-axis direction may increase continuously according to the distance from the photodetector 62C. In other words, the width of the scattering section 166 located farther from the photodetector 62C may be equal to or greater than the width of the scattering section 166 located closer to the photodetector 62C.

[0055] 4 is formed to extend in the Y-axis direction (depth direction on the page), scattering section 166 may be formed to extend in the X-axis direction (left-right direction on the page), and the width in the X-axis direction of scattering section 166 at a position close to photodetector 62C may be equal to or greater than the width in the X-axis direction of scattering section 166 at a position farther from photodetector 62C. In other words, if the direction connecting scattering section 166 and photodetector 62C is defined as a first direction, the width of scattering section 166 that changes depending on the distance from photodetector 62C may be the width in the first direction, or may be the width in a direction perpendicular to the first direction.

[0056] FIG. 5 is a diagram showing an example of the formation width of the scattering section 166A. FIG. 6 is a diagram showing an example of the formation width of the scattering section 166B. As shown in FIG. 5, when the transparent rod 62D is cylindrical, the scattering section 166A is formed to extend along the circumferential direction of the transparent rod 62D. As shown in FIG. 6, when the transparent rod 62D is cylindrical, the scattering section 166B is also formed to extend along the circumferential direction of the transparent rod 62D. Here, the scattering section 166B has a width in the Y-axis direction wider than the width of the scattering section 166A, and therefore has a longer length in the circumferential direction.

[0057] The transparent window 20A in FIG. 4 is made of a transparent material such as a glass material or a transparent resin.

[0058] Since the photodetector 62C in FIG. 4 is disposed outside the vacuum chamber 12, gas that may be emitted from the photodetector 62C can be prevented from entering the vacuum chamber 12.

[0059] 7 and 8 are schematic diagrams showing the light collecting unit 62A and the transparent rod 62D in the detection section. As shown in Fig. 7 and Fig. 8, the light collecting unit 62A includes a collecting lens 162 that collects light incident from the light irradiating section 18 in Fig. 4 on the optical axis of the light, and a light blocking plate 164 that is disposed downstream of the collecting lens 162 in the light path (i.e., on the negative Z-axis direction side in Fig. 7 and Fig. 8) on the optical axis of the light incident from the light irradiating section 18. The light blocking plate 164 is a plate-shaped member that blocks the incident light, and is disposed at the light collecting position of the collecting lens 162, which is farther from the light transmitting section 142 than the collecting lens 162.

[0060] As shown in Figs. 7 and 8, the transparent rod 62D is made of a transparent material such as a glass material such as quartz (SiO2) or a transparent resin (for example, silicon resin). The transparent rod 62D is, for example, a cylindrical rod member, and is formed by extending in a plane (i.e., the XY plane) along the surface of the stage 42 in Fig. 4. If the transparent rod 62D is cylindrical, when the light collected in the light collecting unit 62A is incident on the transparent rod 62D, the total reflection condition is easily satisfied in the transparent rod 62D, and the light can be efficiently propagated. However, the shape of the transparent rod 62D is not limited to a cylindrical shape, and may be, for example, a prismatic shape. Although the transparent rod 62D is rod-shaped in this embodiment, the transparent rod 62D may be, for example, a surface shape corresponding to the entire surface of the stage 42.

[0061] The transparent rod 62D is disposed at a conjugate position with the scattering section 142A with respect to the condenser lens 162 in the Z-axis direction.

[0062] Moreover, the transparent rod 62D may be disposed in a range that overlaps at least with the scattering section 142A in a planar view (for example, a range that includes the scattering section 142A in a planar view). With such an arrangement, the light scattered by the scattering section 142A and further collected by the light collecting unit 62A is efficiently incident on the transparent rod 62D and propagated.

[0063] In addition, a plurality of scattering sections 166 are provided on the lower surface of the transparent rod 62D. Each scattering section 166 scatters the irradiated light while reflecting or transmitting the light. Each scattering section 166 is obtained, for example, by subjecting a glass material to a blasting process or by subjecting a glass material to a frosting process using hydrofluoric acid or the like.

[0064] Each scattering section 166 is disposed in a range overlapping at least with scattering section 142A in a plan view, that is, when viewed from the direction of incidence of light (for example, a range including scattering section 142A in a plan view). Each scattering section 166 may be provided inside or on the upper surface of transparent rod 62D.

[0065] In the case shown in Fig. 7, laser light 18C (parallel light) incident from light irradiator 18 (see Fig. 4) passes only through light transmitting section 142 on stage 42 to reach light collecting unit 62A. On the other hand, in the case shown in Fig. 8, laser light 18C incident from light irradiator 18 (see Fig. 4) passes through scattering section 142A and light transmitting section 142 on stage 42 to reach light collecting unit 62A. Note that, although laser light 18C passes through scattering section 142A and light transmitting section 142 in Fig. 8, laser light 18C may pass only through scattering section 142A.

[0066] 7, laser light 18C passing through light-transmitting portions 142 other than scattering portion 142A reaches light-collecting unit 62A without a large change in the irradiation range and direction of the light. Laser light 18C is then collected by collecting lens 162 in light-collecting unit 62A and enters light-shielding plate 164 arranged at the collecting position of collecting lens 162. Since light is blocked by light-shielding plate 164, laser light 18C does not reach transparent rod 62D located further downstream than light-shielding plate 164 on the path of light along the optical axis of laser light 18C.

[0067] On the other hand, in the case shown in Fig. 8, laser light 18C passing through scattering section 142A in light transmitting section 142 is scattered when passing through scattering section 142A. As a result, laser light 18C reaches focusing unit 62A in a state in which the irradiation range of laser light 18C is expanded by the scattered light (the sandy area in Fig. 8). Laser light 18C is then focused by focusing lens 162 in focusing unit 62A.

[0068] At this time, the laser light 18C, the irradiation range of which has been expanded by the scattering of light in the scattering section 142A, contains many components that are not parallel light, and at least a portion of the components are not focused at the focusing position of the focusing lens 162. Therefore, only a portion of the laser light 18C is blocked by the light blocking plate 164 disposed at the focusing position of the focusing lens 162. In other words, a portion of the laser light 18C that is not blocked by the light blocking plate 164, i.e., the scattered light of the laser light 18C, reaches the transparent rod 62D located further downstream than the light blocking plate 164 on the light path along the optical axis of the laser light 18C.

[0069] Then, the laser light 18C incident on the transparent rod 62D is scattered in the scattering section 166. A part of the scattered laser light 18C is reflected and propagated within the transparent rod 62D, and reaches the fiber 62B connected to the end of the transparent rod 62D.

[0070] As described above, when the laser light 18C irradiated onto the upper surface of the stage 42 is incident on the portion of the light transmitting portion 142 where the scattering portion 142A is formed, the light is condensed by the condensing unit 62A and then reaches the transparent rod 62D. Then, the light that reaches the transparent rod 62D propagates through the transparent rod 62D and further through the fiber 62B connected to the end of the transparent rod 62D, and is then condensed by the condensing lens 62E and detected by the photodetector 62C. Therefore, when the laser light 18C is irradiated onto the scattering portion 142A, the detection unit 62 can detect the scattered light of the laser light 18C, and the position of the irradiated light can be calibrated so that the setting value of the scanner 18A (see FIG. 4) at that time corresponds to the position of the scattering portion 142A. This allows the position of the light irradiated from the light irradiating unit 18 (see FIG. 4) to be aligned with high accuracy when the substrate W arranged on the upper surface of the stage 42 is optically processed in a later step.

[0071] Furthermore, since the light-transmitting portion 142 and the transparent rod 62D onto which light is irradiated by the light irradiation unit 18 (see FIG. 4) are made of a transparent material, even when the light-transmitting portion 142 and the transparent rod 62D are repeatedly irradiated with relatively high-intensity light to calibrate the position of the light irradiated by the light irradiation unit 18 (see FIG. 4), damage to the target onto which light is irradiated for calibration (i.e., the light-transmitting portion 142 and the transparent rod 62D) can be suppressed.

[0072] Furthermore, since the light detected in the detection unit 62 is scattered light and not transmitted light that has passed through the translucent section 142 without being scattered, damage to the detection unit 62 caused by the light can be suppressed compared to the case where unscattered transmitted light is directly detected.

[0073] Fig. 9 is a diagram showing the state of light propagation in the transparent rod 62D. As an example shown in Fig. 9, the laser light 18C incident from the light irradiation unit 18 (see Fig. 4) propagates in the transparent rod 62D and reaches the end of the transparent rod 62D. Then, the light propagates in the fiber 62B connected to the end of the transparent rod 62D in the longitudinal direction (X-axis direction), and is then collected by the collecting lens 62E (see Fig. 4). Then, the light is detected by the photodetector 62C (see Fig. 4) facing the end of the transparent rod 62D via the collecting lens 62E.

[0074] As shown in an example in Figure 9, a scattering section 166B is formed corresponding to the position where laser light 18C is incident, so that laser light 18C incident on transparent rod 62D is scattered in scattering section 166B without passing through transparent rod 62D, making it easier to propagate through transparent rod 62D.

[0075] In addition, because the scattering portions 166A and 166B are provided discretely in the longitudinal direction (X-axis direction) of the lower surface of the transparent rod 62D, the laser light 18C propagating through the transparent rod 62D is less likely to be scattered during propagation, compared to when the scattering portions are provided, for example, over the entire lower surface of the transparent rod 62D. This makes it easier for the laser light 18C to propagate through the transparent rod 62D while satisfying the total reflection condition, and as a result, it is possible to suppress a decrease in the amount of laser light 18C detected by the photodetector 62C.

[0076] Fig. 10 is a diagram showing the state of light propagation in a transparent rod 62D. In Fig. 10, the incident position of the laser light 18C incident on the transparent rod 62D is closer to the fiber 62B connected to the photodetector 62C (see Fig. 4) than in Fig. 9.

[0077] As shown in an example in Figure 10, a scattering section 166A is formed corresponding to the position where laser light 18C is incident, so that laser light 18C incident on the transparent rod 62D is scattered in the scattering section 166A without passing through the transparent rod 62D, making it easier to propagate through the transparent rod 62D.

[0078] Here, the width of the scattering section 166B in the Y-axis direction is wider than the width of the scattering section 166A in the Y-axis direction. Therefore, the laser light 18C incident at a position corresponding to the scattering section 166B as shown in FIG. 9 is more likely to be incident on the corresponding scattering section 166 than the laser light 18C incident at a position corresponding to the scattering section 166A as shown in FIG. 10, and is more likely to be scattered by the scattering section 166 and propagate through the transparent rod 62D. In other words, the laser light 18C incident at a position farther from the photodetector 62C (see FIG. 4) is more likely to be scattered by the corresponding scattering section 166 than the laser light 18C incident at a position closer to the photodetector 62C, and is more likely to propagate through the transparent rod 62D with a large amount of light.

[0079] Then, even if the amount of light of the laser light 18C incident at a position far from the photodetector 62C (see FIG. 4) is reduced due to scattering while propagating in the transparent rod 62D, the amount of light detected by the photodetector 62C is unlikely to differ between the laser light 18C incident at a position close to the photodetector 62C and the laser light 18C incident at a position far from the photodetector 62C. Therefore, since it is possible to set a threshold value (a value for distinguishing from noise) of the amount of light detected regardless of the position at which the laser light 18C is incident, it is possible to effectively detect the propagating laser light 18C while removing noise. As a result, it is possible to improve the light detection accuracy.

[0080] The scattering portion provided on the transparent rod 62D is not limited to being formed by processing the surface of the transparent rod 62D, but may be, for example, a reflective film that functions as a scattering portion applied to the underside of the transparent rod 62D.

[0081] A structure made of processed transparent material such as scattering section 166 is less likely to be damaged by exposure to light and can suppress outgassing, which is a problem under vacuum (or reduced pressure). On the other hand, if a reflective film such as a metal film is provided as the scattering section, the reflectance of light incident on transparent rod 62D is improved, thereby improving the propagation efficiency of the light.

[0082] Fig. 11 is a cross-sectional view that shows a schematic example of the configuration of the transparent rod 162D. As shown in Fig. 11, a reflective film 168 is applied to the lower surface of the transparent rod 162D as a scattering portion. The reflective film 168 is a metal film made of, for example, alumina (aluminum oxide).

[0083] If the reflective film 168 is provided at that location, the light is totally reflected by the reflective film 168 and then propagates through the transparent rod 162D.

[0084] <Effects of the above-described embodiment> Next, examples of effects produced by the above-described embodiments are shown. In the following description, the effects are described based on the specific configurations shown as examples in the above-described embodiments, but they may be replaced with other specific configurations shown as examples in the present specification as long as the same effects are produced. In other words, for convenience, only one of the corresponding specific configurations may be described as a representative below, but the representatively described specific configuration may be replaced with another corresponding specific configuration.

[0085] According to the embodiment described above, the light detection device includes a propagation member and a light detector 62C. Here, the propagation member corresponds to at least one of the transparent rod 62D and the transparent rod 162D, for example. The transparent rod 62D propagates the light irradiated from the light irradiating unit 18. The light detector 62C detects the light propagated by the transparent rod 62D. The transparent rod 62D is provided with a plurality of first scattering units for scattering the light, which are discretely arranged. Here, the first scattering units correspond to at least one of the scattering units 166, 166A, and 166B, for example.

[0086] According to this configuration, excessive diffusion of the laser light 18C while it is propagating through the transparent rod 62D can be suppressed, thereby suppressing a decrease in the amount of the propagating laser light 18C, and as a result, a decrease in the light detection accuracy can be suppressed.

[0087] Furthermore, the same effect can be achieved even if other configurations, examples of which are shown in this specification, are appropriately added to the above configuration, i.e., even if other configurations in this specification that were not mentioned as the above configuration are appropriately added.

[0088] Furthermore, according to the embodiment described above, the photodetector 62C is located opposite the longitudinal end of the transparent rod 62D. The scattering sections 166 are discretely arranged along the longitudinal direction of the transparent rod 62D. This configuration allows light to propagate effectively along the longitudinal direction of the transparent rod 62D.

[0089] Also, according to the embodiment described above, the transparent rod 62D has an end portion facing the photodetector 62C. The width of the second scattering portion, which is one of the scattering portions 166, is equal to or greater than the width of the third scattering portion, which is a scattering portion provided at a position closer to the end portion than the second scattering portion. Here, the second scattering portion corresponds to, for example, the scattering portion 166B. Also, the third scattering portion corresponds to, for example, the scattering portion 166A. According to this configuration, the amount of light scattered by the scattering portion 166B at a position where the propagation distance is long increases relatively compared to the amount of light scattered by the scattering portion 166A at a position where the propagation distance is short so as to offset the decrease in the amount of laser light 18C that occurs according to the propagation distance in the transparent rod 62D, so that the difference in the amount of light propagated through the transparent rod 62D from different entrance positions and detected can be suppressed. As a result, the detection accuracy of light can be improved.

[0090] According to the embodiment described above, the light detection device includes a stage 42. The light irradiation unit 18 irradiates the upper surface of the stage 42 with light. At least one fourth scattering unit for scattering light is provided on at least a part of the stage 42. Here, the fourth scattering unit corresponds to the scattering unit 142A, for example. The scattering unit 142A is made of a transparent material. The transparent rod 62D propagates the light incident through the scattering unit 142A. According to this configuration, since the scattering unit 142A to which light is irradiated is made of a transparent material, even when high-intensity light such as laser light 18C is irradiated, damage to the portion irradiated with light can be reduced. Therefore, the positional accuracy of the light detected by the detection unit 62 is less likely to decrease. By detecting the scattered light scattered by the scattering unit 142A, damage to the detection unit 62 caused by direct irradiation with light can be reduced even when high-intensity light such as laser light 18C is detected.

[0091] Moreover, according to the embodiment described above, each scattering section 166 is disposed in correspondence with the position of the scattering section 142A. With such a configuration, the light scattered by the scattering section 142A and incident on the transparent rod 62D can be further scattered by the scattering section 142A located directly below it, and therefore the light can be efficiently propagated within the transparent rod 62D.

[0092] According to the embodiment described above, the light detection device includes the condensing lens 162 and the light shielding plate 164. The condensing lens 162 collects the light incident through the scattering section 142A. The light shielding plate 164 is disposed at a position farther from the scattering section 142A than the condensing lens 162. The light shielding plate 164 is disposed at the light collecting position of the condensing lens 162. The transparent rod 62D propagates the light collected by the condensing lens 162. According to this configuration, by detecting the scattered light scattered by the scattering section 142A with the light detector 62C while blocking the transmitted light with the light shielding plate 164, it is possible to reduce damage to the detection section 62 caused by direct irradiation of light even when detecting high-intensity light such as the laser light 18C.

[0093] Furthermore, according to the embodiment described above, the multiple scattering portions 166 are formed by blasting the surface of the transparent rod 62D. With such a configuration, it is possible to form scattering portions that are less susceptible to damage due to light irradiation and that can suppress outgassing, which is a problem under vacuum (or reduced pressure).

[0094] Moreover, according to the embodiment described above, the multiple first scattering portions are the reflective films 168 applied to the lower surface of the transparent rod 162D. With this configuration, the reflectance of the lower surface of the transparent rod 62D is increased by the reflective films 168 provided discretely on the lower surface, thereby suppressing excessive diffusion during light propagation and improving the propagation efficiency of the light that has entered the transparent rod 62D.

[0095] Moreover, according to the embodiment described above, the light irradiated from the light irradiating unit 18 is laser light 18C. With such a configuration, even when high-intensity light such as laser light 18C is irradiated, excessive diffusion during propagation can be suppressed, thereby suppressing a decrease in the amount of propagated light.

[0096] Furthermore, according to the embodiment described above, the light detection device includes a chamber in which the transparent rod 62D is housed. Here, the chamber corresponds to, for example, the vacuum chamber 12. The light detector 62C detects the light propagated by the transparent rod 62D outside the vacuum chamber 12. With this configuration, the light detector 62C of the detection unit 62 is provided outside the vacuum chamber 12, so that outgassing emitted from the light detector 62C can be prevented from occurring inside the vacuum chamber 12.

[0097] <Modifications of the above-described embodiments> In the embodiments described above, the material, composition, dimensions, shape, relative positional relationship, or implementation conditions of each component may be described, but these are merely examples in all respects and are not limiting.

[0098] Thus, numerous variations and equivalents not shown are contemplated within the scope of the technology disclosed herein, including, for example, modifying, adding, or omitting at least one component.

[0099] In addition, in the embodiments described above, when a material name is mentioned without being specifically specified, it is understood that the material may contain other additives, such as an alloy, unless a contradiction arises. [Explanation of symbols]

[0100] 1 Light irradiation device 12 Vacuum chamber 12A,12B,12C opening 14 External fixing part 14B External parts 14A, 14C Column members 16A, 16B Bellows 18B,62E,162 Condenser lens 18 Light irradiation unit 18A Scanner 18C Laser light 20 Irradiation window 20A Transparent window 21 Vacuum Pump 22 Control section 24 Mount 42 Stages 42A Target Placement Area 42B Position calibration area 44 Slider 46 Base 48 Linear Guide 50 Linear motor mechanism 52 Lift pin mechanism 52A Lift Pin 62 Detection unit 62A Light Concentrator Unit 62B Fiber 62C Photodetector 62D, 162D Transparent rod 142 Translucent part 142A,166,166A,166B Scattering part 164 Shade 168 Reflective film

Claims

1. a light detection device that detects light irradiated from a light irradiating unit, a propagation member for propagating the light irradiated from the light irradiation unit; a photodetector for detecting the light propagated by the propagating member; the propagation member is provided with a plurality of first scattering sections arranged discretely to scatter the light, With more stages, the light irradiation unit irradiates the light onto an upper surface of the stage; At least one fourth scattering unit for scattering the light is provided on at least a portion of the stage; the fourth scattering portion is made of a transparent material, The propagation member propagates the light incident via the fourth scattering section. Light detection device.

2. 2. The light detection device according to claim 1, the photodetector is located opposite an end of the transmission member in a longitudinal direction; The plurality of first scattering sections are discretely arranged along a longitudinal direction of the propagation member. Light detection device.

3. 3. The light detection device according to claim 1, the transmitting member has an end facing the photodetector; a width of a second scattering section which is one of the plurality of first scattering sections is equal to or greater than a width of a third scattering section which is a scattering section provided at a position closer to the end section than the second scattering section; Light detection device.

4. 4. The light detection device according to claim 3, Each of the first scattering sections is disposed to correspond to a position of the fourth scattering section. Light detection device.

5. 5. The photodetector according to claim 3, a condenser lens for condensing the light incident via the fourth scattering portion; a light blocking plate disposed at a position farther from the fourth scattering unit than the condensing lens and at a condensing position of the condensing lens, The propagation member propagates the light condensed by the condensing lens. Light detection device.

6. A light detection device according to any one of claims 1 to 5, The plurality of first scattering portions are formed by blasting a surface of the propagation member. Light detection device.

7. A light detection device according to any one of claims 1 to 5, The plurality of first scattering portions are reflective films applied to a lower surface of the propagation member. Light detection device.

8. A light detection device according to any one of claims 1 to 7, The light irradiated from the light irradiation unit is laser light. Light detection device.

9. A light detection device according to any one of claims 1 to 8, a chamber containing the transmitting member; the photodetector detects the light transmitted by the transmitting member outside the chamber; Light detection device.

10. At least one light irradiating unit for irradiating light; and a light detection device according to any one of claims 1 to 9. Light irradiation device.

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