JP2023021607A - Light irradiation device and light irradiation method - Google Patents

Abstract

To restrain deterioration in detection accuracy caused by irradiation of light.SOLUTION: A light irradiation device includes a stage which is at least partially formed of a transparent material, and at least one light irradiation unit for irradiating an upper surface of the stage with light. The stage is provided with a light transmitting portion for transmitting the light therethrough and at least one scattering portion for scattering the light. The light irradiation device further includes a detector for detecting at least one of the light transmitted through the light transmitting portion and the light scattered by the scattering portion, and a specifying unit for specifying the position of at least one of the light transmitting portion and the scattering portion based on the amount of detected light.SELECTED DRAWING: Figure 6

Description

The technology disclosed in this specification relates to technology for detecting emitted light.

2. Description of the Related Art Conventionally, an optical processing technique for processing an object by light irradiation such as laser light irradiation has been used (see Patent Document 1, for example).

Japanese Patent Application Laid-Open No. 2006-272430

In order to improve the processing accuracy in the above optical processing technology, it is important to control the position irradiated with light with high accuracy.

As a method of detecting the position irradiated with light, for example, there is a method of detecting the position irradiated with light by capturing an image of the light with an area camera. However, the accumulation of damage to the members or optical elements placed where the light is irradiated lowers the detection accuracy, especially when high-intensity light such as laser light is detected. was there.

The technology disclosed in the specification of the present application has been made in view of the problems described above, and is a technology for suppressing deterioration in detection accuracy caused by light irradiation.

A light irradiation device, which is a first aspect of the technology disclosed in the present specification, includes a stage at least partly made of a transparent material, and at least one light irradiation device for irradiating an upper surface of the stage with light. The stage is provided with a light-transmitting portion for transmitting the light and at least one scattering portion for scattering the light, and the light transmitted through the light-transmitting portion and the a detection unit for detecting at least one of the light scattered by the scattering unit; and a position of at least one of the translucent unit and the scattering unit based on the amount of the detected light. and a specifying unit to be used.

A light irradiation device, which is a second aspect of the technology disclosed in the present specification, relates to the light irradiation device, which is the first aspect, wherein the specifying unit detects a , to locate the boundary between the translucent portion and the scattering portion.

A light irradiation device that is a third aspect of the technology disclosed in this specification relates to the light irradiation device that is the first or second aspect, and the scattering section is formed of two triangles in plan view of the stage. is a butterfly shape in which one vertices of are connected to each other.

A light irradiation device that is a fourth aspect of the technology disclosed in the specification of the present application relates to the light irradiation device that is any one aspect of the first to third aspects, and the light emitted from the light irradiation unit The light is laser light.

A light irradiation device according to a fifth aspect of the technology disclosed in this specification relates to the light irradiation device according to any one of the first to fourth aspects, wherein the detection unit includes the light transmission unit and a condenser lens for condensing at least one of the light transmitted through and the light scattered by the scattering section.

A light irradiation device according to a sixth aspect of the technology disclosed in the present specification is related to the light irradiation device according to the fifth aspect, further comprising a chamber containing the stage, wherein the chamber is filled with a vacuum. Alternatively, it is under a reduced pressure atmosphere, and the detection unit includes a fiber that propagates the light condensed by the condenser lens to the outside of the chamber, and a fiber that is arranged outside the chamber and propagated by the fiber and a photodetector that detects the light.

A light irradiation method according to a seventh aspect of the technology disclosed in the present specification includes a step of irradiating an upper surface of a stage made of a transparent material with light, and the stage has a structure for transmitting the light. and at least one scattering portion for scattering the light, and detect at least one of the light transmitted through the light transmitting portion and the light scattered in the scattering portion. and specifying the position of at least one of the translucent portion and the scattering portion based on the amount of light detected.

According to at least the first and seventh aspects of the technology disclosed in the specification of the present application, since the scattering portion irradiated with light is made of a transparent material, when high-intensity light such as laser light is irradiated, Even so, it is possible to reduce damage to the portion irradiated with light. Therefore, the positional accuracy of the light detected by the detector is less likely to decrease.

Also, the objects, features, aspects, and advantages associated with the technology disclosed herein will become more apparent from the detailed description and accompanying drawings presented below.

It is a perspective view which shows roughly the example of a structure of the light irradiation apparatus regarding embodiment. 2 is a cross-sectional view showing an example of the internal configuration of a vacuum chamber and the peripheral configuration of the light irradiation device according to the embodiment; FIG. FIG. 3 is a perspective view mainly showing a light irradiation unit and a stage in the configuration shown in the example of FIG. 2; FIG. 3 is a cross-sectional view mainly showing an example of a configuration of a light irradiation unit and a stage among the configurations illustrated in FIG. 2; FIG. 4 is a schematic diagram showing the configuration and action of a light collecting unit; FIG. 4 is a schematic diagram showing the configuration and action of a light collecting unit; FIG. 4 is a plan view showing an example of the shape of a scattering portion; FIG. 8 is a diagram showing an example of detection signals from a photodetector obtained when a scattering portion having the shape shown in FIG. 7 is scanned in the X-axis direction; FIG. 10 is a cross-sectional view showing an example of a configuration in which a plurality of light irradiation units are provided;

Embodiments will be described below with reference to the attached drawings. In the following embodiments, detailed features and the like are also shown for technical explanation, but they are examples, and not all of them are necessarily essential features for enabling the embodiments.

It should be noted that the drawings are shown schematically, and for the convenience of explanation, some omissions or simplifications of the configuration may be made in the drawings as appropriate. In addition, the mutual relationship of sizes and positions of configurations shown in different drawings is not necessarily described accurately and can be changed as appropriate. Also, in drawings such as plan views that are not cross-sectional views, hatching may be added to facilitate understanding of the contents of the embodiments.

In addition, in the description given below, the same components are denoted by the same reference numerals, and their names and functions are also the same. Therefore, a detailed description thereof may be omitted to avoid duplication.

Also, in the descriptions in this specification, when a component is described as “comprising,” “including,” or “having,” unless otherwise specified, it is an exclusive term that excludes other components. not an expression.

In addition, even if ordinal numbers such as “first” or “second” are used in the description given in this specification, these terms are used to understand the content of the embodiments. They are used for the sake of convenience, and the subject matter of the embodiments is not limited to the order or the like that can occur with these ordinal numbers.

In addition, in the descriptions given in the specification of the present application, expressions such as “… positive direction of axis” or “… negative direction of axis” refer to the direction along the arrow of the illustrated , the direction opposite to the arrow is the negative direction.

Also, expressions indicating relative or absolute positional relationships in the descriptions described herein, such as “in one direction”, “along one direction”, “parallel”, “perpendicular”, “center ”, “Concentric”, “Coaxial”, etc., unless otherwise specified, refer to cases where the positional relationship is strictly indicated, and cases where the angle or distance is displaced within a tolerance or equivalent function. shall include

Also, in the descriptions provided herein, specific positions or orientations such as "top", "bottom", "left", "right", "side", "bottom", "front" or "back" are used for convenience in order to facilitate understanding of the content of the embodiments, and may be used when the embodiments are actually implemented. is independent of the position or orientation of

<Embodiment>
A light irradiation device according to this embodiment will be described below. In the following embodiments, as an example, a light irradiation apparatus in which the inside of the chamber is in a vacuum or a reduced pressure atmosphere is described, but the same can be applied even when the inside of the chamber is not in a vacuum.

<Regarding the configuration of the light irradiation device>
FIG. 1 is a perspective view schematically showing an example of the configuration of a light irradiation device 1 according to this embodiment. In FIG. 1, the illustration of the chamber frame that supports the vacuum chamber 12 or the wiring that is actually connected is omitted for the sake of convenience. It should be noted that the "vacuum" in the present embodiment is desirably a high vacuum (for example, 0.00001 Pa) in order to prevent deterioration of the characteristics of the substrate W, but if the degree of vacuum does not reach the high vacuum, shall also include

As an example is shown in FIG. 1, the light irradiation device 1 includes a vacuum chamber 12, an external fixed part 14 such as a granite surface plate, and the vacuum chamber 12 and the external fixed part 14, which are made of, for example, stainless steel. A bellows 16A which is a stretchable member, a light irradiation unit 18 which irradiates light into the vacuum chamber 12, a vacuum pump 21 which reduces the pressure in the vacuum chamber 12 to a vacuum state, and a light irradiation device 1. and a control unit 22 for controlling the driving unit. In the above description, bellows made of stainless steel or the like is shown as an example of the elastic member. An elastic member made of resin or the like may be employed. Further, the shape of the stretchable member may not be a bellows shape like the bellows 16A described above.

The vacuum chamber 12 has a space in which the substrate W is accommodated. The substrate W to be processed includes, for example, a semiconductor wafer, a glass substrate for a liquid crystal display device, a flat panel display (FPD) substrate such as an organic EL (electroluminescence) display device, an optical disk substrate, a magnetic disk substrate, and a magneto-optical substrate. It includes disk substrates, photomask glass substrates, ceramic substrates, field emission display (FED) substrates, solar cell substrates, and the like. The substrate W is, for example, a substrate having a thin film formed on its upper surface.

An opening 12A is formed in 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 evacuated. Other configurations accommodated inside the vacuum chamber 12 will be described later.

The light irradiation unit 18 irradiates the upper surface of the substrate W housed in the vacuum chamber 12 with light. At this time, the substrate W is aligned in advance by a detection unit 62 or the like, which will be described later. The light irradiation unit 18 ablates the substrate W by irradiating it with laser light, for example. The light irradiator 18 may irradiate light such as an electron beam depending on the purpose of processing. The light irradiation unit 18 irradiates the upper surface of the substrate W accommodated in the vacuum chamber 12 from outside the vacuum chamber 12 through an irradiation window (transparent plate made of quartz or the like) (not shown). Light scans the upper surface of the substrate W by moving the substrate W in the vacuum chamber 12 relative to the light irradiation unit 18 or by controlling the optical system in the light irradiation unit 18 . Further, the light irradiation section 18 is arranged on the upper surface of the mount 24 fixed to the external fixing section 14 .

The control unit 22 includes, for example, a hard disk drive (ie, HDD), a random access memory (ie, RAM), a read only memory (ie, ROM), a flash memory, a volatile Or non-volatile semiconductor memory, magnetic disk, flexible disk, optical disk, compact disk, mini disk or storage device including memory (storage medium) including DVD, for example, the storage device, external CD-ROM, external A processing circuit such as a central processing unit (i.e., CPU) that executes programs stored in a DVD-ROM or an external flash memory, and a mouse, keyboard, touch panel, or various switches , an input device to which information can be input, and an output device, such as a display, a liquid crystal display, or a lamp, to which information can be output.

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 the output control of the vacuum pump 21, and furthermore, each driving unit described later (for example, the driving unit of the linear motor mechanism Alternatively, it controls the drive of the lift pin mechanism). Further, the control unit 22 can specify the position of the stage on which the substrate W is placed based on the detected value of the light emitted from the light irradiation unit 18, as will be described later.

FIG. 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 this embodiment. As an example is shown in FIG. 2, inside the vacuum chamber 12 are a stage 42 on which the substrate W is placed, and a slider 44 which is movable in the Y-axis direction and supports the stage 42 from below. a base 46 fixed to the external fixing portion 14 independently of the vacuum chamber 12; a linear guide 48 fixed to the base 46 and extending in the Y-axis direction; A linear motor mechanism 50 for moving in the axial direction, 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, and a lift pin mechanism 52 below the stage 42 (not shown). 2) is provided on the Z-axis negative direction side).

The stage 42 holds the substrate W substantially horizontally while directing the processing surface of the substrate W upward. A detailed configuration of the stage 42 will be described later. The slider 44 that supports the stage 42 is moved in the Y-axis direction by the linear motor mechanism 50, and the light irradiated from the light irradiation unit 18 is scanned in the X-axis direction, whereby the processing area of the substrate W in plan view is changed. can be scanned with light. Alternatively, by scanning the light irradiated from the light irradiation unit 18 in the X-axis direction and the Y-axis direction, it is possible to scan the entire processing region of the substrate W with the light in plan view. Note that the lift pin mechanism 52 is fixed to the base 46 .

The linear motor mechanism 50 is fixed to the external fixing part 14 positioned on the side of the vacuum chamber 12 through an opening 12B formed in the side surface of the vacuum chamber 12 . Specifically, linear motor mechanism 50 is fixed to the end of hollow post 14A passing through bellows 16A welded to opening 12B. At this time, wiring and the like connected to the linear motor mechanism 50 are led out of the vacuum chamber 12 through the inside of the columnar member 14A. The columnar member 14A included in the external fixing portion 14 is fixed to the external member 14B included in the external fixing portion 14. As shown in FIG. Also, the columnar member 14A does not come into contact with the bellows 16A connected to the side surface of the vacuum chamber 12. As shown in FIG.

The base 46 is fixed to the external fixing part 14 positioned 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 the end of the columnar member 14C passing through the bellows 16B welded to the opening 12C. The columnar member 14C included in the external fixing portion 14 is fixed to the external member 14B included in the external fixing portion 14. As shown in FIG. Also, the columnar member 14C does not come into contact with the bellows 16B connected to the bottom surface of the vacuum chamber 12. As shown in FIG.

In FIG. 2, the external fixtures 14 are arranged laterally and downwardly of the vacuum chamber 12, but it is not essential that the external fixtures 14 at these positions be continuous, but distributed at these positions. It may be provided as such, or may be provided only at one of the positions. In addition, the vacuum chamber 12 is supported and fixed vertically by a chamber frame (not shown) separately from the bellows 16B.

The detector 62 can detect the light emitted from the light emitter 18 below the stage 42 . A detailed configuration of the detection unit 62 will be described later.

FIG. 3 is a perspective view mainly showing the light irradiation section 18 and the stage 42 in the configuration shown in FIG. 3 shows a state in which the substrate W is placed on the upper surface of the stage 42. As shown in FIG. The light irradiation unit 18 can scan the light irradiation direction in the X-axis direction in FIG. 3, and the stage 42 can be moved in the Y-axis direction by a linear motor mechanism 50 (see FIG. 2). Therefore, the light emitted 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. FIG.

As shown in FIG. 3, the stage 42 calibrates a target placement region 42A in which the substrate W to be irradiated with light by the light irradiation unit 18 is placed, and the position of the light irradiated by the light irradiation unit 18. A position calibration area 42B is provided as an area for performing calibration.

The target placement area 42A places the substrate W at a specific position within the target placement area 42A. Thereby, the positional relationship between the stage 42 and the substrate W is specified in advance. In the position calibration area 42B, the position of the light irradiated from the light irradiation section 18 into the position calibration area 42B is detected by the detection section 62 (see FIG. 2). Then, in the position calibration region 42B, prior to the optical processing of the substrate W in the target placement region 42A, the correspondence relationship between the set value of the direction of the light irradiated from the light irradiation unit 18 and the detected irradiation position of the light. is calibrated.

At least part of the position calibration region 42B is provided with a light transmitting portion 142 that transmits light. The translucent portion 142 is made of a transparent material such as a glass material (SiO ₂ ) or transparent resin (for example, silicon resin). The translucent part 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 irradiation section 18 to the light transmission section 142 is transmitted from the upper surface to the lower surface of the stage 42 .

At least one (two in FIG. 3) scattering portions 142A are provided in at least a portion of the light transmitting portion 142 . The scattering section 142A is made of a transparent material, and scatters and reflects or transmits the irradiated light. The position where the scattering section 142A is provided is a specific position on the stage 42 . That is, the position of the scattering portion 142A on the entire stage 42 is specified in advance. In FIG. 3, each scattering section 142A is arranged at the end of the light irradiation region of the light irradiation section 18 in the X-axis direction, but the position where the scattering section 142A is arranged is a specific position on the stage 42. It is not limited to the end portion of the light irradiation area of the light irradiation section 18 as long as it is sufficient. The scattering portion 142A has a property of scattering incident light, and can be obtained, for example, by subjecting a glass material to blasting or frosting using hydrofluoric acid or the like. 3, each scattering portion 142A is formed on the upper surface of the translucent portion 142, but at least one scattering portion 142A may be formed on the lower surface of the translucent portion 142. FIG.

In the case shown in FIG. 3, the target placement area 42A and the position calibration area 42B are separate areas, but these areas may overlap at least partially. That is, the translucent part 142 may be provided in at least a part of the area where the substrate W is arranged. In such a case, for example, the position of the light irradiated from the light irradiation unit 18 may be calibrated at the position where the substrate W is arranged in a state where the substrate W is not arranged.

Further, the translucent portion 142 may have a scattering portion 142A formed over its entire range. In other words, there may be no portion where only light is transmitted, and light scattering may occur over the entire range of the light transmitting portion 142 .

In FIG. 3, the translucent portions 142 are provided extending in the X-axis direction, and scattering portions 142A are provided at respective ends in the X-axis direction. It may be divided into parts. However, when a plurality of scattering portions 142A are provided in the integrally formed translucent portion 142 (that is, the case shown in FIG. 3), when the translucent portion 142 is manufactured with a transparent material, The light transmitting portion 142 can be attached (fitted in in the case of FIG. 3) to the stage 42 while maintaining the positional accuracy among the plurality of scattering portions 142A. Therefore, since there is no positional deviation between the scattering portions 142A when attached to the stage 42, it is possible to maintain high accuracy of calibration performed using the plurality of scattering portions 142A.

FIG. 4 is a sectional view mainly showing an example of the configuration of the light irradiation section 18 and the stage 42 among the configurations shown in FIG. As an example is shown in FIG. 4, the light irradiation unit 18 includes a scanner 18A such as a galvanometer mirror or a polygon mirror that controls the direction of the light to be irradiated in the X-axis direction and the Y-axis direction, and light from a light source (not shown). and a condensing lens 18B for condensing the light. In FIG. 4, the light irradiated through the condensing lens 18B and the irradiation window 20 made of quartz or the like is, for example, laser light 18C. The laser beam 18C can scan the substrate W placed on the upper surface of the stage 42 in the X-axis direction under the control of the scanner 18A. Here, the light irradiation unit 18 is preferably capable of controlling light in the X-axis direction and the Y-axis direction, but the light irradiation unit 18 can control light in either the X-axis direction or the Y-axis direction. There may be.

The stage 42 includes a light transmitting portion 142 formed in the position calibration region 42B (see FIG. 3) and a scattering portion 142A formed on the upper surface of the light transmitting portion 142. As shown in FIG. The laser beam 18C emitted from the light irradiation unit 18 can scan in the X-axis direction at least within a range reaching the scattering unit 142A.

A detector 62 for detecting light is arranged below the stage 42 . The detection unit 62 includes a light collecting unit 62A that collects light within the vacuum chamber 12, a fiber 62B that propagates the light collected by the light collecting unit 62A out of the vacuum chamber 12, and a fiber 62B that transmits light to the outside of the vacuum chamber 12. and a photodetector 62C for detecting light propagated to. Since the photodetector 62</b>C is arranged outside the vacuum chamber 12 , it is possible to suppress the intrusion into the vacuum chamber 12 of gas that may be emitted from the photodetector 62</b>C.

5 and 6 are schematic diagrams showing the configuration and action of the condensing unit 62A. As examples are shown in FIGS. 5 and 6, the light collecting unit 62A includes a light collecting lens 162 which collects the light on the optical axis of the light incident from the light irradiation section 18 (see FIG. 4). Prepare.

In the case shown in FIG. 5, the laser light 18C (parallel light) incident from the light irradiation section 18 (see FIG. 4) passes only through the light transmission section 142 of the stage 42 and reaches the light collecting unit 62A. ing. On the other hand, in the case shown in FIG. 6, the laser beam 18C incident from the light irradiation section 18 (see FIG. 4) passes through the scattering section 142A and the translucent section 142 in the stage 42 and reaches the light collecting unit 62A. have reached. Although the laser beam 18C passes through the scattering portion 142A and the translucent portion 142 in FIG. 6, the laser beam 18C may pass through only the scattering portion 142A.

In the case shown in FIG. 5, the laser beam 18C passing through the translucent portion 142 other than the scattering portion 142A reaches the condensing unit 62A without a large change in the irradiation range and direction of the light. Most of the laser light 18C is condensed by the condensing lens 162 in the condensing unit 62A and enters the fiber 62B arranged at the condensing position of the condensing lens 162. FIG.

On the other hand, in the case shown in FIG. 6, the laser light 18C passing through the scattering portion 142A in the translucent portion 142 undergoes light scattering when passing through the scattering portion 142A. Then, the laser beam 18C reaches the light collection unit 62A in a state in which the irradiation range of the laser beam 18C is expanded by the scattered light (the sandy portion in FIG. 6). Then, the laser beam 18C is condensed by the condensing lens 162 in the condensing unit 62A.

At this time, the laser beam 18C whose irradiation range is expanded due to the scattering of light in the scattering portion 142A contains many components that are not parallel light, and at least some of the components are at the condensing position of the condensing lens 162. Not focused. Therefore, only a portion of the laser light 18C, excluding the laser light 18C not condensed at the condensing position, reaches the fiber 62B.

As described above, when the laser beam 18C irradiated onto the upper surface of the stage 42 passes through the light transmitting portion 142 other than the scattering portion 142A, most of it is condensed by the condensing lens 162 into the fiber 62B. When the light reaches and passes through the scattering portion 142A of the translucent portion 142, only a portion thereof is condensed by the condensing lens 162 and reaches the fiber 62B. The light reaching fiber 62B is then detected by photodetector 62C (see FIG. 4).

Therefore, the laser beam 18C detected by the detection unit 62 (see FIG. 4) varies depending on whether the laser beam 18C is applied to the translucent portion 142 other than the scattering portion 142A or to the scattering portion 142A. Different amount of light. Therefore, based on the light amount value output from the photodetector 62C, the control unit 22 determines the timing at which the detected light amount changes, and the timing at which the boundary formed with the scattering portion 142A in the translucent portion 142 is irradiated with light. can be Further, the control unit 22 makes the setting value of the scanner 18A (see FIG. 4) at that timing correspond to the position of the scattering unit 142A (specifically, the boundary position), thereby adjusting the position of the irradiated light. can be calibrated. As a result, when the substrate W placed on the upper surface of the stage 42 is optically processed in a later process, the position of the light emitted from the light irradiation unit 18 is aligned with high accuracy under the control of the control unit 22. be able to.

In addition, since the light-transmitting portion 142 irradiated with light by the light irradiation portion 18 is made of a transparent material, the light-transmitting portion 142 is repeatedly compared in order to calibrate the position of the light irradiated by the light irradiation portion 18 . Even in the case of irradiation with light having a relatively high intensity, it is possible to suppress damage to the target (that is, the light-transmitting portion 142) irradiated with light for calibration.

<Regarding the shape of the scattering part>
FIG. 7 is a plan view showing an example of the shape of the scattering portion 142A. As an example is shown in FIG. 7, the scattering section 142A is provided on the upper surface of the stage 42 (see FIGS. 3 and 4) so as to extend in the X-axis direction and the Y-axis direction. are arranged facing each other and their vertices are connected to each other (butterfly shape). With such a shape, the width of the scattering portion 142A in the X-axis direction (the total width of the formed regions) increases toward the center in the Y-axis direction. Alternatively, the width of the scattering portion 142A in the Y-axis direction becomes smaller toward the central portion in the X-axis direction.

FIG. 8 is a diagram showing an example of a detection signal at the photodetector 62C (see FIG. 4) obtained when the scattering portion 142A having the shape shown in FIG. 7 is scanned in the X-axis direction. . In the example shown in FIG. 8, light is detected by the photodetector 62C at constant sampling timings (T1, T2, T3, T4 and T5) and the detection signal S is output. 3, see FIG. 4) has been changed in the Y-axis direction. Among the detection signals S shown in FIG. 8, the black ones indicate those with strong signal intensity (that is, the detected amount of light is large), and the white ones indicate those with weak signal intensity (that is, the detected amount of light less).

When the photodetector 62C detects the light irradiated to the butterfly-shaped scattering portion 142A (see FIG. 7), as shown in FIG. At the end of the side, the region where the signal intensity is weak is divided into two locations in the X-axis direction, so the intensity of the detection signal S increases during the period between the sampling timing T1 and the sampling timing T5. It fluctuates (varies) around the sampling timing T3. On the other hand, in the central portion in the Y-axis direction, regions with weak signal strength are continuously arranged in the X-axis direction, so the intensity of the detection signal S is is unshakable.

Then, it can be seen that the position in the Y-axis direction during scanning in which the detection signal S does not fluctuate is the central position in the Y-axis direction of the scattering portion 142A. That is, by comparing fluctuations of the detection signal S in multiple scans, the central position of the scattering portion 142A can be specified with high accuracy.

Further, the position in the X-axis direction corresponding to the midpoint of the period in which the intensity of the detection signal S is weakened (including the period in which it is continuously weakened and the period in which it is intermittently weakened) is the position of the scattering portion 142A. It can be seen that it is the center position in the X-axis direction. That is, when the detection signal S is output at the sampling timings T1 and T5, it can be seen that the sampling timing T3 is the central position.

On the other hand, when the scattering part (butterfly shape), which is a shape obtained by rotating the shape shown in FIG. 7 by 90 degrees, is scanned in the X-axis direction (this is the shape shown in FIG. (corresponding to the case where the scattering portion is scanned in the Y-axis direction), at the end on the positive side of the Y-axis and the end on the negative side of the Y-axis, regions with weak signal strength are long and continuous in the X-axis direction. In addition, in the central portion in the Y-axis direction, the area where the signal strength is weak is arranged the shortest in the X-axis direction.

Then, it can be seen that the position in the Y-axis direction during scanning where the detection signal S with the weakest signal intensity is detected is the central position in the Y-axis direction of the scattering portion. That is, the center position of the scattering part can be specified with high accuracy by comparing the length of time for which the signal intensity weakens in multiple scans.

Further, the position in the X-axis direction corresponding to the middle point of the period in which the detection signal S is weakened (sampling timing T3 when the detection signal S is output from sampling timing T1 to sampling timing T5) is the scattering part. is the center position in the X-axis direction.

Since the shape of the scattering portion is butterfly in this way, the central position of the scattering portion in the X-axis direction or the Y-axis direction can be specified with high accuracy. Therefore, the position of the light emitted from the light emitting unit 18 (see FIG. 4) can be calibrated and aligned with high accuracy.

Here, the shape of the scattering portion is not limited to the one in which the region formed toward the central portion in the X-axis direction becomes gradually smaller as shown in FIGS. The region formed toward the central portion in the direction may be discontinuously smaller, or the region formed toward the central portion may be larger in both the X-axis direction and the Y-axis direction. may Moreover, the shape of the outer edge of the scattering portion is not limited to the straight line shown in FIGS. 7 and 8, and may include a curved line at least in part.

<When a plurality of light irradiation units are provided>
FIG. 9 is a cross-sectional view showing an example of a configuration in which a plurality of light irradiation units are provided. As an example is shown in FIG. 9, a light irradiation device is provided with a plurality of light irradiation units 118 and light irradiation units 218 .

The light irradiation unit 118 includes a scanner 118A such as a galvanomirror that controls the direction of the light to be irradiated in the X-axis direction, and a condenser lens 118B that collects light from a light source (not shown). In FIG. 9, light emitted through a condenser lens 118B and an irradiation window 20A made of quartz or the like is, for example, a laser beam 118C. The substrate W placed on the upper surface can be scanned in the X-axis direction.

Similarly, the light irradiation unit 218 includes a scanner 218A such as a galvanomirror that controls the direction of the light to be irradiated in the X-axis direction, and a condenser lens 218B that collects light from a light source (not shown). In FIG. 9, light emitted through a condenser lens 218B and an irradiation window 20B made of quartz or the like is, for example, a laser beam 218C. The substrate W placed on the upper surface can be scanned in the X-axis direction.

Here, the light irradiation region of the light irradiation portion 118 in the X-axis direction extends from a position corresponding to the scattering portion 142B formed in the light transmitting portion 142 to a position corresponding to the scattering portion 142C formed in the light transmitting portion 142. is. On the other hand, the light irradiation region of the light irradiation portion 118 in the X-axis direction extends from the position corresponding to the scattering portion 142C formed in the light transmitting portion 142 to the position corresponding to the scattering portion 142D formed in the light transmitting portion 142. is. In other words, the scattering portion 142C is arranged at the connecting portion between the light irradiation region of the light irradiation portion 118 and the light irradiation region of the light irradiation portion 218 .

The detection unit 62 is arranged below the stage 42 at positions corresponding to the scattering units 142B, 142C, and 142D. The condensing unit 62A in each detection section 62 is arranged on the optical axis of the light incident from the corresponding light irradiation section.

By arranging the scattering portions 142B, 142C, and 142D in this manner, the connection portion between the light irradiation region of the light irradiation portion 118 and the light irradiation region of the light irradiation portion 218 is positioned by the common scattering portion 142C. Therefore, misalignment between the two light irradiation regions can be suppressed.

<About the effect produced by the embodiment described above>
Next, examples of effects produced by the embodiments described above are shown. In the following description, the effect will be described based on the specific configuration exemplified in the embodiment described above. may be substituted with other specific configurations shown. That is, hereinafter, for convenience, only one of the specific configurations to be associated may be described as a representative, but other specific configurations to which the specific configurations described as representative are associated may be replaced with a similar configuration.

According to the embodiments described above, the light irradiation device includes the stage 42, at least one light irradiation section 18 (or light irradiation section 118 or light irradiation section 218), and a specifying section. Here, the specifying unit corresponds to, for example, the control unit 22 and the like. At least a portion of the stage 42 is made of a transparent material. The light irradiation unit 18 irradiates the upper surface of the stage 42 with light. The stage 42 is provided with a light transmitting portion 142 for transmitting light and at least one scattering portion 142A (or scattering portion 142B, scattering portion 142C, scattering portion 142D) for scattering light. The detector 62 detects at least one of the light transmitted through the translucent portion 142 and the light scattered by the scattering portion 142A. Control unit 22 identifies the position of at least one of translucent portion 142 and scattering portion 142A based on the amount of light detected.

According to such a configuration, the scattering portion 142A irradiated with light is made of a transparent material. Damage to (scattering portion 142A) can be reduced. Therefore, the positional accuracy of the light detected by the detector 62 is less likely to decrease. Further, by detecting both the transmitted light passing through only the translucent portion 142 and the scattered light passing through the scattering portion 142A with the detecting portion 62, it is possible to obtain a sufficient amount of light to maintain the detection accuracy. In addition, since the light scattered by the scattering portion 142A has a wider irradiation range than the light transmitted through the light transmitting portion 142, the amount of light incident on the fiber 62B decreases as a whole. Therefore, based on the difference between the amount of transmitted light and the amount of scattered light, it can be determined whether the light detected by the detection unit 62 is light transmitted through the light transmission unit 142 or light scattered by the scattering unit 142A. You can determine if there is Therefore, it is possible to identify whether or not the scattering section 142A is arranged at the position of the upper surface of the stage 42 irradiated with light. That is, the position of at least one of the translucent portion 142 and the scattering portion 142A can be specified.

It should be noted that when other configurations exemplified in the present specification are appropriately added to the above configurations, that is, when other configurations in the present specification that are not mentioned as the above configurations are added as appropriate can produce a similar effect.

Further, according to the embodiments described above, the controller 22 identifies the position of the boundary between the translucent part 142 and the scattering part 142A based on the difference in the amount of detected light. According to such a configuration, the position at which the amount of detected light changes based on the difference between the amount of transmitted light and the amount of scattered light is the boundary between the translucent portion 142 and the scattering portion 142A. position can be specified.

Moreover, according to the embodiments described above, the scattering section 142A has a butterfly shape in which the vertices of two triangles are connected to each other in a plan view of the stage 42 . According to such a configuration, when the detection signal S does not fluctuate, or when the intensity of the detection signal S becomes weak, it can be seen that the center position of the scattering portion 142A is the middle point. That is, by comparing the intensity of the detection signal S detected in multiple scans, the center position of the scattering portion 142A can be specified with high accuracy.

Moreover, according to the embodiments described above, the light irradiated from the light irradiation unit 18 is laser light. With such a configuration, damage to the scattering portion 142A is reduced even when high-intensity light such as laser light is irradiated.

Also, according to the embodiments described above, the detector 62 comprises a condenser lens 162 . Condensing lens 162 collects at least one of the light transmitted through translucent portion 142 and the light scattered by scattering portion 142A. According to such a configuration, it becomes easier to secure the amount of light for maintaining the detection accuracy by condensing the light.

Moreover, according to the embodiments described above, the light irradiation device includes a chamber in which the stage 42 is enclosed. Here, the chamber corresponds to, for example, the vacuum chamber 12 or the like. Here, the inside of the vacuum chamber 12 is under a vacuum or reduced pressure atmosphere. The detector 62 includes a fiber 62B and a photodetector 62C. Fiber 62B propagates light collected by collecting lens 162 out of vacuum chamber 12 . Photodetector 62C is located outside vacuum chamber 12 and detects light propagated by fiber 62B. According to such a configuration, since the photodetector 62C of the detection unit 62 is provided outside the vacuum chamber 12, outgas emitted from the photodetector 62C is prevented from entering the vacuum chamber 12. be able to.

According to the embodiments described above, in the light irradiation method, the upper surface of the stage 42 made of a transparent material is irradiated with light. Here, the stage 42 is provided with a light transmitting portion 142 for transmitting light and at least one scattering portion 142A for scattering light. At least one of the light transmitted through the translucent portion 142 and the light scattered by the scattering portion 142A is detected. Then, the position of at least one of the translucent portion 142 and the scattering portion 142A is specified based on the amount of light detected.

According to such a configuration, the scattering portion 142A irradiated with light is made of a transparent material. Damage to (scattering portion 142A) can be reduced. Therefore, the positional accuracy of the light detected by the detector 62 is less likely to decrease. Further, by detecting both the transmitted light passing through only the translucent portion 142 and the scattered light passing through the scattering portion 142A with the detecting portion 62, it is possible to obtain a sufficient amount of light to maintain the detection accuracy. Also, based on the difference between the amount of transmitted light and the amount of scattered light, it is determined whether the light detected by the detection unit 62 is the light transmitted through the light transmission unit 142 or the light scattered by the scattering unit 142A. can be determined. Therefore, the position of at least one of the translucent portion 142 and the scattering portion 142A can be specified.

In addition, when other configurations whose examples are shown in this specification are added to the above configurations as appropriate, that is, when other configurations in this specification that are not mentioned as the above configurations are added as appropriate can produce a similar effect.

<Regarding Modifications of the Embodiments Described Above>
In the embodiments described above, the material, material, size, shape, relative arrangement relationship, implementation conditions, etc. of each component may be described, but these are only examples in all aspects. and shall not be limiting.

Accordingly, myriad variations and equivalents, not exemplified, are envisioned within the scope of the technology disclosed herein. For example, where at least one component is transformed, where it is added or where it is omitted shall be included.

Further, in the embodiments described above, when a material name is described without being specified, unless there is a contradiction, the material contains other additives, such as an alloy. shall be included.

1 Light irradiation device 18 Light irradiation unit 18B Condensing lens 18C Laser light 42 Stage 62 Detecting unit 62B Fiber 62C Photodetector 118 Light irradiation unit 118B Condensing lens 118C Laser light 142 Translucent unit 142A Scattering unit 142B Scattering unit 142C Scattering unit 142D scattering section 162 condenser lens 218 light irradiation section 218B condenser lens 218C laser light

Claims (7)

a stage at least partially composed of a transparent material;
At least one light irradiation unit for irradiating the upper surface of the stage with light,
The stage is provided with a light transmitting portion for transmitting the light and at least one scattering portion for scattering the light,
a detection unit for detecting at least one of the light transmitted through the light transmission unit and the light scattered by the scattering unit;
a specifying unit that specifies the position of at least one of the translucent unit and the scattering unit based on the amount of the detected light,
Light irradiation device. A light irradiation device according to claim 1,
The specifying unit specifies the position of the boundary between the translucent unit and the scattering unit based on a difference in light intensity of the detected light.
Light irradiation device. A light irradiation device according to claim 1 or 2,
The scattering part has a butterfly shape in which the vertices of two triangles are connected to each other in a plan view of the stage,
Light irradiation device. A light irradiation device according to any one of claims 1 to 3,
The light irradiated from the light irradiation unit is laser light,
Light irradiation device. A light irradiation device according to any one of claims 1 to 4,
The detection unit includes a condenser lens for condensing at least one of the light transmitted through the light transmission unit and the light scattered by the scattering unit.
Light irradiation device. A light irradiation device according to claim 5,
further comprising a chamber containing the stage,
The inside of the chamber is under a vacuum or reduced pressure atmosphere,
The detection unit is
a fiber that propagates the light collected by the collecting lens out of the chamber;
a photodetector located outside the chamber and detecting the light propagated by the fiber;
Light irradiation device. A step of irradiating the upper surface of a stage made of a transparent material with light,
The stage is provided with a light transmitting portion for transmitting the light and at least one scattering portion for scattering the light,
detecting at least one of the light transmitted through the translucent portion and the light scattered by the scattering portion;
Further comprising a step of specifying the position of at least one of the translucent portion and the scattering portion based on the amount of light detected.
Light irradiation method.

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