KR20210134326A - Light source apparatus for exposure, exposure apparatus, and exposure method - Google Patents

Abstract

A light source device for exposure capable of synthesizing light from a plurality of LED elements having different peak wavelengths and having a compact configuration, an exposure apparatus using the light source device, and an exposure method are provided. A first LED array 71 having a plurality of first LED elements 72 emitting light of a first peak wavelength, and a plurality of second LED elements emitting light of a second peak wavelength different from the first peak wavelength a second LED array 75 having a 76, and two dichroic films 81 for transmitting light in a specific wavelength band and reflecting light in other wavelength bands, the first and second A light synthesizing element 80 for synthesizing the light of the LED arrays 71 and 75, and a fly's eye lens 65 into which the light synthesized by the light synthesizing element 80 is incident is provided.

Description

Light source apparatus for exposure, exposure apparatus, and exposure method

The present invention relates to a light source device for exposure, an exposure device, and an exposure method, and more particularly, to a light source device for exposure using light irradiated from an LED element as a light source, an exposure device, and an exposure method.

DESCRIPTION OF RELATED ART Conventionally, a mercury lamp has been used as a UV light source in the exposure apparatus used for lithography, such as a flat panel display, a printed circuit board, and a semiconductor element. However, in recent years, restrictions on the use of mercury have become stricter, and LEDs of UV light sources are recommended.

Here, when the conventional resist matched with the mercury lamp and the wavelength range is used as it is, the wavelength band of the short-wavelength LED element is narrow compared with the mercury lamp. Therefore, a combination of LED elements of a plurality of wavelengths corresponding to g-line (436 nm), h-line (405 nm), and i-line (365 nm) of a mercury lamp with strong output from a high-pressure mercury lamp is used as a UV light source. One is known (for example, refer patent documents 1 and 2).

In Patent Document 1, UV light from a plurality of LED elements irradiating light with wavelengths corresponding to g-line (436 nm), h-line (405 nm), and i-line (365 nm) with strong output from a high-pressure mercury lamp A light source device is described in which ? is multiplexed using an X-shaped dichroic mirror. Further, in Patent Document 2, a plurality of LED light sources each emitting UV light in the wavelength bands of 360 nm to 380 nm, 390 nm to 410 nm, and 420 nm to 450 nm, and a plurality of dices arranged for each LED light source An LED-type ultraviolet irradiator provided with a low-light mirror is disclosed. Moreover, in patent document 2, it is described using the UV LED light emitted with the wavelength of less than 300 nm, for example, a nominally 240 nm wavelength.

Japanese Laid-Open Patent Publication No. 2018-10294 Japanese Patent Laid-Open No. 2010-263218

By the way, as for the set wavelength of a UV light source, the wavelength which sensitizes a resist efficiently has little power consumption of an LED light source, and can reduce the labor of cooling by heat_generation|fever of a light source, and it is preferable. Generally, in exposure apparatuses, there is a request to make a UV light source compact in order to reduce the number of parts, to effectively utilize the space in the apparatus, and to reduce the weight. Although a condensing lens is attached to each LED element, the light from an LED array does not become parallel and the light tends to diffuse especially unless optical members, such as a convex lens, are used separately. For this reason, there is a high need to shorten the optical path length and make the light source device compact. In particular, in the exposure apparatus for a display, since it is necessary to expose a large area at once, the size of a light source also becomes large, and the necessity of compactization is high.

Although the light source device described in Patent Document 1 uses an X-shaped dichroic mirror to reduce the installation area, there is room for further compactness. Moreover, the LED type ultraviolet irradiator of patent document 2 uses three or more dichroic mirrors in series, and there existed room for further improvement as a compact LED light source.

Further, when the inventor tested using a conventional resist, a resist having a higher exposure sensitivity at a shorter wavelength than the i-line (365 nm) was found. This is because the polymerization initiator of the resist has absorption not only at the absorption peak wavelength but also at the wavelengths around it, but when the absorption wavelength range extends to the visible light range, problems may occur depending on the use of the resist. It is thought that this is because the wavelength is set to a shorter wavelength than the g-line, h-line, and i-line of the mercury lamp. As such a use, the resist for color filters of a display or an image sensor is mentioned, for example. Accordingly, a light source device capable of sensitizing such a resist more efficiently has also been desired.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and its object is to synthesize light from a plurality of LED elements having different peak wavelengths and compactly constitute a light source device for exposure, an exposure apparatus using the light source device, and exposure It's about providing a way.

The above object of the present invention is achieved by the following constitution.

(1) a first LED array having a plurality of first LED elements emitting light of a first peak wavelength;

a second LED array having a plurality of second LED elements emitting light of a second peak wavelength different from the first peak wavelength;

a light synthesizing element for synthesizing the light of the first and second LED arrays;

a fly-eye lens into which the light synthesized by the optical synthesis element is incident;

A light source device for exposure comprising:

The optical synthesis element includes two dichroic films that transmit light in a specific wavelength band and reflect light in other wavelength bands, and the two dichroic films form the fly's eye lens from the optical synthesis element. is inclined with respect to the optical axis direction toward

The first LED array is disposed on the opposite side of the fly's eye lens with respect to the optical synthesis element in the optical axis direction,

and the second LED array intersects the optical axis direction and is disposed on the side of the optical synthesis element.

(2) a peak wavelength of light irradiated from either one of the first LED element and the second LED element is 360 to 380 nm;

The peak wavelength of light irradiated from the other of the first LED element and the second LED element is 300 to 355 nm or 385 to 410 nm,

The light source device for exposure according to (1), wherein the peak wavelengths of the first LED element and the second LED element are separated by 20 nm or more.

(3) the length of the second LED array disposed on the side of the optical synthesis device,

The light source device for exposure according to (1) or (2), wherein the length of the first LED array disposed on the opposite side of the fly-eye lens with respect to the optical synthesis element is shorter than the length of the light source device for exposure.

(4) The light source device for exposure according to any one of (1) to (3), wherein the optical synthesis element is two dichroic mirrors or a dichroic prism.

(5) the photosynthetic device includes two dichroic mirrors each having the dichroic film,

The light source device for exposure according to (1), wherein an end of each dichroic mirror is cut parallel to the optical axis direction.

(6) further comprising two dichroic mirror fixing frames to which the dichroic mirrors are respectively fixed, and two dichroic mirror fixing frames open on a side where the two dichroic mirrors are in close contact with each other;

The light source device for exposure according to (5), wherein the tip of the dichroic mirror fixed frame on the fly's eye lens side is cut at a right angle to the optical axis direction.

(7) Any of (1) to (6), wherein the second LED array has two types of second LED arrays alternately arranged at intervals of 90° on a plane orthogonal to the optical axis direction. The light source device for exposure as described in one.

(8) an illuminating device having the light source device for exposure according to any one of (1) to (7);

a work support for supporting the work;

a mask support for supporting the mask;

An exposure apparatus comprising: irradiating light irradiated from the illumination device to the work through the mask to transfer the pattern of the mask onto the work.

(9) An exposure method in which a pattern of the mask is transferred to the work by irradiating the light irradiated from the illuminating device to the work through the mask using the exposure apparatus according to (8).

(10) a plurality of first LED elements emitting light of a first peak wavelength in the range of 360 to 380 nm corresponding to the photosensitive wavelength of the polymerization initiator of the photosensitive material formed on the substrate; A plurality of second LED elements emitting light of two peak wavelengths,

to provide

The light of the first LED element and the light of the second LED element are mixed and emitted to the fly's eye lens, the light source device for exposure.

(11) The light source device for exposure according to (10), comprising an LED array in which the first LED element and the second LED element are arranged in a mixture.

(12) a first LED array having the plurality of first LED elements;

a second LED array having the plurality of second LED elements;

a light synthesizing element for synthesizing the light of the first and second LED arrays;

to provide

In the optical synthesis device, a dichroic film that transmits light of a specific wavelength band and reflects light of other wavelength bands is disposed inclined with respect to an optical axis direction from the optical synthesis device toward the fly's eye lens,

Either one of the first LED array and the second LED array is disposed on the opposite side of the fly's eye lens with respect to the optical synthesis element in the optical axis direction,

The light source device for exposure according to (9), wherein the other of the first LED array and the second LED array intersects the optical axis direction and is disposed on the side of the optical synthesis element.

(13) A lighting device having the light source device for exposure according to any one of (10) to (12);

a work support for supporting the work;

a mask support for supporting the mask;

An exposure apparatus comprising: irradiating light irradiated from the illumination device to the work through the mask to transfer the pattern of the mask onto the work.

(14) An exposure method in which a pattern of the mask is transferred to the work by irradiating the light irradiated from the illuminating device to the work through the mask using the exposure apparatus according to (13).

According to the light source device for exposure of the present invention, the exposure device using the light source device, and the exposure method, a light source device capable of synthesizing light from a plurality of LED elements having different peak wavelengths is configured compactly, and the synthesized light By effectively sensitizing the photosensitive material, the exposure operation efficiency can be improved.

BRIEF DESCRIPTION OF THE DRAWINGS It is a front view of the exposure apparatus which concerns on 1st Embodiment of this invention.
FIG. 2 is a diagram showing the configuration of the lighting device shown in FIG. 1 .
Fig. 3 is a schematic configuration diagram of the light source device according to the first embodiment.
Fig. 4 (a) is a graph showing the transmittance of a dichroic mirror as an example, and (b) is an enlarged view of section IV of (a).
Fig. 5 (a) is a graph showing the reflectance of the dichroic mirror of Fig. 4 , and (b) is an enlarged view of the V part of (a).
6 is a schematic configuration diagram of a light source device according to a second embodiment.
Fig. 7(a) is a side view showing a mounted state of a dichroic mirror as a light source device according to a third embodiment, and Fig. 7(b) is an arrow view viewed from the direction A of (a).
Fig. 8(a) is a side view showing another mounting state of a dichroic mirror as a light source device of a modified example of the third embodiment, and Fig. 8(b) is an arrow view viewed from the direction B in (a).
Fig. 9 is a schematic plan view showing two types of second LED arrays and two dichroic mirrors arranged on a plane perpendicular to the optical axis direction in the case of the light source device according to the fourth embodiment.
Fig. 10 is a schematic configuration diagram of a light source device according to a modified example of the present invention using a dichroic prism.
11 is a front view of an LED array that is a light source device according to another modification of the present invention.
12 is a front view of an LED array which is a light source device according to still another modification of the present invention.

(First embodiment)

EMBODIMENT OF THE INVENTION Hereinafter, 1st Embodiment of the exposure apparatus which concerns on this invention is described in detail based on drawing. 1, the proximity exposure apparatus PE uses the mask M smaller than the workpiece|work W as a to-be-exposed material, while holding the mask M by the mask stage (mask support part) 1, , for pattern exposure from the illumination device 3 in a state in which the work W is held by the work stage (work support part) 2, the mask M and the work W are brought close to each other and are opposed by a predetermined exposure gap By irradiating the light of the mask M toward the mask M, the pattern of the mask M is exposed and transferred onto the work W. Moreover, the work stage 2 is moved stepwise with respect to the mask M in the biaxial direction of an X-axis direction and a Y-axis direction, and exposure transcription|transfer is performed for every step.

In order to move the work stage 2 stepwise in the X-axis direction, on the apparatus base 4, an X-axis stage feed mechanism 5 for step-moving the X-axis feeder 5a in the X-axis direction is provided. On the X-axis feeder 5a of the X-axis stage feed mechanism 5, in order to step-move the work stage 2 in the Y-axis direction, the Y-axis for stepping the Y-axis feeder 6a in the Y-axis direction A stage transfer mechanism 6 is provided. On the Y-axis transfer table 6a of the Y-axis stage transfer mechanism 6, the work stage 2 is provided. On the upper surface of the work stage 2, the work W is held in a vacuum-sucked state by a work chuck or the like. Moreover, in the side part of the work stage 2, the board|substrate side displacement sensor 15 for measuring the lower surface height of the mask M is arrange|positioned. Accordingly, the substrate-side displacement sensor 15 is movable in the X and Y axis directions together with the work stage 2 .

On the device base 4, guide rails 51 of a plurality of X-axis linear guides (four in the embodiment shown in the drawing) are arranged in the X-axis direction, and on each guide rail 51, an X-axis feeder A slider 52 fixed to the lower surface of (5a) is provided. Thereby, the X-axis feeder 5a is driven by the 1st linear motor 20 of the X-axis stage feed mechanism 5, and can reciprocate along the guide rail 51 in the X-axis direction. In addition, on the X-axis feeder 5a, guide rails 53 of a plurality of Y-axis linear guides are arranged in the Y-axis direction, and on each guide rail 53, on the lower surface of the Y-axis feeder 6a. A fixed slider 54 is provided. Thereby, the Y-axis feeder 6a is driven by the 2nd linear motor 21 of the Y-axis stage feed mechanism 6, and can reciprocate along the guide rail 53 in the Y-axis direction.

Between the Y-axis stage transport mechanism 6 and the work stage 2, in order to move the work stage 2 in the vertical direction, the positioning resolution is relatively coarse, but the moving stroke and the moving speed are large. ) device 7 and the vertical coarse motion device 7 enable positioning at high resolution and reduce the gap between the opposing surfaces of the mask (M) and the workpiece (W) by moving the work stage up and down finely. An up-and-down fine-moving device 8 for fine adjustment by a fixed amount is provided.

The vertical coarse motion apparatus 7 moves the work stage 2 up and down with respect to the fine motion stage 6b by an appropriate drive mechanism provided in the fine motion stage 6b mentioned later. The stage coarse motion shaft 14 fixed at four points on the bottom surface of the work stage 2 is engaged with the linear motion bearing 14a fixed to the fine motion stage 6b, and is vertical with respect to the fine motion stage 6b. is guided to Moreover, even if the resolution of the vertical coarse motion apparatus 7 is low, it is preferable that repeat positioning precision is high.

The vertical fine movement device 8 includes a fixing table 9 fixed to the Y-axis feeder 6a, and a guide rail 10 of a linear guide mounted to the fixing table 9 with its inner end inclined obliquely downward. A ball screw nut (not shown) is connected to the slide body 12 reciprocating along the guide rail 10 via a slider 11 provided over the guide rail 10. , the upper end surface of the slide body 12 is in contact with the flange 12a fixed to the micro-movement stage 6b so as to be able to slide freely in the horizontal direction.

Then, when the screw shaft of the ball screw is rotationally driven by the motor 17 attached to the fixing table 9 , the nut, the slider 11 and the slide body 12 are integrated to move in an oblique direction along the guide rail 10 . It moves, and accordingly, the flange 12a moves up and down finely.

In addition, instead of driving the slide body 12 with the motor 17 and the ball screw, you may make the vertical fine movement device 8 drive the slide body 12 with a linear motor.

This vertical fine movement device 8 is provided in one end (left end side in Fig. 1) at one end (left end side in Fig. 1) of the Z-axis feeder 6a in the Y-axis direction, two units at the other end side, a total of three units, and each is independently driven. is to be controlled. Thereby, the vertical fine movement apparatus 8 is based on the measurement result of the gap amount of the mask M and the workpiece|work W at multiple points by the gap sensor 27, The height of the flange 12a of three points|pieces Independently fine-tune the height and inclination of the workstation (2).

In addition, when the height of the work stage 2 can fully be adjusted by the vertical fine motion apparatus 8, you may abbreviate|omit the vertical coarse motion apparatus 7. As shown in FIG.

Further, on the Y-axis feeder 6a, a bar mirror 19 facing the Y-axis laser interferometer 18 for detecting the position of the work stage 2 in the Y direction, and the X-axis direction of the work stage 2 A bar mirror (not shown together) opposite to the X-axis laser interferometer that detects the position of is installed. The bar mirror 19 opposing the Y-axis laser interferometer 18 is disposed along the X-axis direction on one side of the Y-axis feeder 6a, and the bar mirror opposing the X-axis laser interferometer is Y-axis feed It is arranged along the Y-axis direction from one end side of the base 6a.

The Y-axis laser interferometer 18 and the X-axis laser interferometer are each always disposed so as to face the corresponding bar mirror and supported by the apparatus base 4 . In addition, two Y-axis laser interferometers 18 are provided spaced apart in the X-axis direction. The two Y-axis laser interferometers 18 detect the Y-axis direction position and yaw error of the Y-axis feeder 6a and, further, the work stage 2 via the bar mirror 19 . Further, the X-axis laser interferometer detects the position of the X-axis feeder 5a and, further, the work stage 2 in the X-axis direction through the opposing bar mirrors.

The mask stage 1 is inserted through a gap into a mask base 24 made of a substantially rectangular frame, and a central opening of the mask base 24, and moves in X, Y, and θ directions (in the X, Y plane). and a mask frame 25 supported as possible, the mask frame 24 being held in position above the work stage 2 by a post 4a protruding from the apparatus base 4 have.

A frame-shaped mask holder 26 is formed on the lower surface of the central opening of the mask frame 25 . That is, on the lower surface of the mask frame 25, a plurality of mask holder suction grooves connected to a vacuum type suction device (not shown) are formed, and the mask holder 26 is connected to the mask frame 25 through the plurality of mask holder suction grooves. is retained by adsorption.

In the lower surface of the mask holder 26, a plurality of mask suction grooves (not shown) for sucking the periphery on which the mask pattern of the mask M is not drawn are drilled and formed, and the mask M is the mask suction. Through the groove, it is freely detachably held on the lower surface of the mask holder 26 by a vacuum suction device (not shown).

As shown in FIG. 2 , the illumination device 3 of the exposure device PE of the present embodiment includes a light source device 70 for ultraviolet irradiation and a fly-eye lens 65 of the light source device 70 . A plane mirror 66 for changing the direction of the optical path EL, a collimation mirror 67 for irradiating the light from the light source device 70 as parallel light, and the parallel light for irradiating the mask M toward the mask M A flat mirror 68 is provided.

In the lighting device 3 , the light irradiated from the light source device 70 is incident on the incident surface of the fly's eye lens 65 . The fly's eye lens 65 is used in order to make the illuminance distribution as uniform as possible in the irradiation surface of the incident light. Then, the light emitted from the emitting surface of the fly's eye lens 65 is converted into parallel light while the traveling direction is changed by the plane mirror 66 , the collimation mirror 67 , and the plane mirror 68 . . Then, the parallel light is irradiated as light for pattern exposure substantially perpendicular to the surface of the mask M held by the mask stage 1, and further, the work W held by the work stage 2, and the mask The pattern of (M) is transferred by exposure onto the work (W).

Next, with reference to FIG. 3, the light source device 70 is demonstrated in detail. The light source device 70 of the present embodiment includes first and second LED arrays 71 and 75 irradiating light having different peak wavelengths from each other, and the first and second LED arrays 71 and 75 irradiated from the first and second LED arrays 71 and 75 . A dichroic mirror 80 (80A, 80B) which is a light synthesizing element for synthesizing light having different peak wavelengths, and a fly's eye lens 65 including a plurality of lens elements 65a arranged in a matrix form; .

As for the 1st LED array 71, the some 1st LED element 72 is two-dimensionally aligned and arrange|positioned. The plurality of first LED elements 72 irradiate UV light having a peak wavelength (first peak wavelength) to any one of, for example, 360 to 380 nm. Moreover, the peak wavelength of the 1st LED element 72 becomes like this. Preferably it is 360-370 nm, More preferably, it is 365 nm.

In the second LED array 75 , a plurality of second LED elements 76 are two-dimensionally arranged. The plurality of second LED elements 76 irradiate UV light having a peak wavelength (second peak wavelength) to any of 300 to 355 nm or 385 to 410 nm, for example. Moreover, as for the peak wavelength of the 2nd LED element 76, the direction of 300-355 nm is preferable, More preferably, it is 325-355 nm, More preferably, it is 335 nm.

In addition, the 1st LED element 72 and the 2nd LED element 76 are selected so that the peak wavelength of each light may be spaced apart by 20 nm or more. The reason that the peak wavelengths of the light of the first and second LED elements 72 and 76 are spaced apart by 20 nm or more is that the two wavelengths synthesized in the dichroic mirror 80 are spaced apart by 20 nm or more from the viewpoint of performance. Follow what you need

In addition, when the peak wavelength of the 1st LED element 72 is set to 365 nm, for example, the peak wavelength of the 2nd LED element 76 may be set to 345 nm or less, or is set to 385 nm or more. may be

The dichroic mirror 80, which is a photosynthetic element, forms a thin film (dichroic film) 81 such as a multilayer dielectric film on a plate-shaped transparent medium 82 such as glass or plastic to form a light having a specific wavelength band. is an optical element having characteristics of reflecting and transmitting light in other wavelength bands.

In the dichroic mirror 80, two dichroic mirrors 80A and 80B (two dichroic films 81) of approximately equal length L3 fly from the dichroic mirror 80. It is inclined with respect to the optical axis direction L toward the eye lens 65 (that is, the direction along the optical path EL), and is arranged in a substantially V shape so as to be in close contact with the fly's eye lens side. Further, in the present embodiment, the two dichroic mirrors 80A and 80B are combined at an angle of approximately 90°.

Then, the opening side of the two V-shaped dichroic mirrors 80A and 80B (in the optical axis direction L, the side opposite to the fly's eye lens 65 with respect to the dichroic mirror 80, in FIG. 3 ) The 1st LED array 71 is arrange|positioned opposite to the left side in this case. In addition, the second V-shaped dichroic mirrors 80A and 80B intersecting (orthogonal in the present embodiment) with respect to the optical axis direction L, respectively (up and down in Fig. 3) An LED array 75 is disposed. Accordingly, the first LED array 71 and the second LED array 75 both face the V-shaped dichroic mirror 80A or 80B at an angle of approximately 45°.

In addition, in the present embodiment, the fact that the second LED array 75 is orthogonal to the optical axis direction L means that the second LED array 75 incident on the fly's eye lens 65 is not only strictly orthogonal. ) includes cases where the direction of light from ) is orthogonal to an acceptable degree.

Further, the number of the second LED elements 76 in the second LED array 75 is 1/2 of the number of the first LED elements 72 in the first LED array 71 . That is, the length L2 of the second LED array 75 is approximately 1/2 the length L1 of the first LED array 71, and the length L3 of the dichroic mirror 80A or 80B. ) is 1/√2 of Accordingly, all the light emitted from the first LED array 71 passes through the dichroic mirror 80A or 80B, and all the light emitted from the two second LED arrays 75 is dichroic. The light reflected by the mirror 80A or 80B and irradiated from the first LED array 71 and the light irradiated from the second LED array 75 are synthesized and incident on the incident surface of the fly's eye lens 65 do.

In this way, the two dichroic mirrors 80A and 80B are arranged in a substantially V-shape so as to be in close contact with the fly's eye lens 65 side, and the first LED array 71 is disposed in the optical axis direction L , arranged on the opposite side of the fly's eye lens 65 with respect to the V-shaped dichroic mirrors 80A, 80B, the second LED array 75 is orthogonal to the optical axis direction L, and the V-shaped dichroic By dividing and arranging the loic mirrors 80A and 80B on both sides, the length from the first LED array 71 to the fly's eye lens 65 can be shortened, and the light source device 70 can be configured compactly. can Moreover, the 1st LED array 71 and the fly's eye lens 65 are arrange|positioned adjacently, and optical efficiency improves.

In addition, in FIG. 3, the dominant wavelength which has a peak wavelength in any one of 360-380 nm for the 1st LED array 71, and the 2nd LED array 75 for 300-355 nm or 385-410 nm, for example. It is set as the sub-wavelength which has a peak wavelength in any one of them. However, in this embodiment, it is not limited to this, The sub-wavelength which has a peak wavelength in either 300-355 nm or 385-410 nm, for example, the 1st LED array 71, and the 2nd LED array 75 ) may be the dominant wavelength having a peak wavelength in any of 360 to 380 nm.

Moreover, since the light reflected by the dichroic mirrors 80A, 80B has better optical efficiency than the transmitted light, it can select suitably according to the photosensitivity of the resist used. Moreover, the length of the 1st LED array 71, the 2nd LED array 75, and the dichroic mirrors 80A, 80B can also be changed according to specification.

The second LED array 75 passes through the interface of the dichroic mirror 80 once upon reflection, whereas the first LED array 71 passes the interface of the dichroic mirror 80 twice. pass through In addition, although the light of the 2nd LED array 75 is reflected by the dichroic mirror 80, since the film thickness of the dichroic mirror 80 is proportional to a reflected wavelength, the wavelength of the short reflected light is the side. This makes it possible to make a film thickness thin, and manufacture becomes easy. For this reason, when using the dichroic mirror 80, the first LED array 71 has a relatively long peak wavelength, and the second LED array 75 has a relatively short peak wavelength. it is preferable

Specifically, preferred combinations of the peak wavelength of the first LED array 71 and the peak wavelength of the second LED array 75 include the following two combinations (A) and (B).

(A) Peak wavelength of the first LED array 71: 360 to 380 nm

Peak wavelength of the second LED array 75: 300 to 355 nm

(B) Peak wavelength of the first LED array 71: 385 to 410 nm

Peak wavelength of the second LED array 75: 360 to 380 nm

In addition, in general, the exposure sensitivity at the time of exposure using an LED element having each peak wavelength with respect to a color resist matching the absorption peak wavelength region to the i-line (365 nm) was confirmed by testing, as shown in Table 1 A difference in sensitivity as shown was obtained. In addition, Table 1 is making the reference of 365 nm.

As can be seen from Table 1, for example, since the exposure sensitivity of light with a wavelength of 330 nm to light with a wavelength of 365 nm is three times, equivalent performance is obtained even when the output of the 365 nm LED element is about 30%. . Therefore, by combining two types of LED elements in accordance with the absorption peak wavelength range of the resist, it becomes possible to increase the efficiency of the exposure process by shortening the exposure time.

As an example, when the 2nd LED element 76 is made into 365 nm which is a main wavelength, and the 1st LED element 72 is made into 385 nm of a sub-wavelength, the LED element of a long wavelength region (385 nm) is a 365-nm LED. Compared with the element, although the exposure sensitivity is low, the output is high, and the transmittance|permeability is high so that a wavelength is long. Specifically, as shown in FIG. 4 , the 385 nm LED element arranged in the first LED array 71 has a transmittance of about 98%, and is arranged in the second LED array 75 as shown in FIG. 5 . The 365 nm LED element that has been used has a reflectance of approximately 100%, resulting in a loss of approximately 2% as a whole. 4 is a graph showing the transmittance of the dichroic mirror 80 as an example, and FIG. 5 is a graph showing the reflectance of the dichroic mirror 80 of FIG. 4 . Each graph shows that the light emitted from each LED element 72, 76 is substantially at an angle (θ1, θ2) of 42° to 48° with respect to the surface of the dichroic mirror 80A, 80B by a condensing lens ( 3), the transmittance and reflectance at θ1, θ2 = 42°, 45°, and 48° are shown, assuming that the light is incident on the dichroic mirrors 80A and 80B.

Thus, by combining the said two types of LED elements, exposure time can be shortened. In addition, as a combination of two types of LED elements, a peak wavelength of 365 nm and a thing of 330 nm may be used, and exposure time can be shortened with the same output.

Moreover, by combining the LED element used as a dominant wavelength, and the LED element which has a wavelength longer than the dominant wavelength, stabilization of the pattern to form is attained.

For example, when exposure is performed using only a short-wavelength LED element having a peak wavelength of 365 nm, the curing of the formed pattern is weak depending on the resist, and the pattern is easily peeled off in the developing step. Peeling tends to occur at the ends of the pattern, and is due to the leakage light passing through the pattern of the mask and the polymerization initiator of the resist. Usually, for suppression of peeling, it is necessary to increase the exposure time or to adjust the front and rear steps. By using in combination an LED element having a wavelength of 385 nm, which light can easily reach, the pattern can be stabilized.

(Second Embodiment)

Next, the light source device 70 of 2nd Embodiment is demonstrated with reference to FIG. As shown in FIG. 6 , in the light source device 70 of the present embodiment, both ends 83 of the two dichroic mirrors 80A and 80B are connected from the dichroic mirror 80 to the fly's eye lens 65 . ) and cut parallel to the optical axis direction L. As a result, the dichroic films 81 of the two dichroic mirrors 80A and 80B are in contact with each other at the V-shaped top and bottom, so that the dichroic mirrors 80A, 80B have the first The light irradiated from the LED array 71 is uniformly transmitted over the entire width direction (direction orthogonal to the optical axis direction L) of the dichroic mirror 80 , and is emitted from the second LED array 75 . The irradiated light can be reflected in a wide range, and the efficiency is improved.

In addition, also in this case, the 1st LED array 71 and the 2nd LED array 75 can be arrange|positioned with respect to the two dichroic mirrors 80A, 80B interchangeably.

Other configurations and actions are the same as those of the first embodiment of the present invention.

(Third embodiment)

Next, the light source device 70 of 3rd Embodiment is demonstrated with reference to FIG. As shown in Fig. 7, in this embodiment, the fixing method of the two dichroic mirrors 80A and 80B described in the above embodiment is explained using the two dichroic mirror fixing frames 85. do.

In the dichroic mirror fixing frame 85, three frames 85a, 85b, 85c covering three sides among the four sides of the rectangular dichroic mirrors 80A, 80B are combined in a substantially U-shape, It has a shape in which the side surfaces of the mutually opposing sides of the dichroic mirrors 80A, 80B are opened. And, the dichroic mirrors 80A and 80B are fitted with a groove 86 formed in the frame body 85a of the dichroic mirror fixing frame 85 having one side of the substantially U-shaped dichroic mirror fixing frame 85, The upper surfaces of the low-light mirrors 80A and 80B are pressed toward the frame body 85b by the push screw 87 formed in the frame body 85c via the cushioning material 88, and are dichroic. It is fixed to the wing mirror fixing frame (85).

Further, in Fig. 7, corresponding to the second embodiment, the tip portions 83 of the two dichroic mirrors 80A and 80B butted in a V shape, and the dichroic mirrors 80A and 80B are fixed, respectively. The distal end 85d of the dichroic mirror fixed frame 85 (frames 85b, 85c) is cut parallel to the optical axis direction L from the dichroic mirror 80 toward the fly's eye lens 65, It is closely adhered so that there is no gap, and is preferably adhered so that there is no gap.

Further, the tip portion 85d on the fly's eye lens side of the dichroic mirror fixed frames 85 (frames 85b, 85c) combined in a V shape is directed from the dichroic mirror 80 toward the fly's eye lens 65. It is cut at a right angle to the optical axis direction L to form a plane that is flush with each other. Accordingly, the two dichroic mirrors 80A, 80B can be brought closer to the fly's eye lens 65 by the cut length of the dichroic mirror fixing frame 85, so that the efficiency is improved and the light source The device 70 can be made compact. In addition, in Fig. 7(b) of the dichroic mirror fixed frame 85 (frame body 85a, 85b, 85c) supporting the dichroic mirrors 80A, 80B, the range outside the arrow indicates that of the exposure light. It is arranged outside the optical path, so that the dichroic mirror fixing frame 85 does not become an obstacle to exposure.

Further, as a modification of the present embodiment, as shown in Fig. 8, in the dichroic mirror fixed frame 85, grooves 86 are formed in three frame bodies 85a, 85b, 85c, respectively. , each side (three sides) of the dichroic mirrors 80A and 80B may be fitted into the three grooves 86 and fixed with an adhesive. Moreover, as shown in FIG. 7, the front-end|tip part 83 of the two dichroic mirrors 80A, 80B, and the front-end|tip part 85d of the two dichroic mirror fixing frames 85 are closely_contact|adhered so that there may be no gap. and preferably adhered so that there is no gap.

(Fourth embodiment)

Next, the light source device 70 of 4th Embodiment is demonstrated with reference to FIG. As shown in Fig. 9, in the present embodiment, on the side of the two V-shaped dichroic mirrors 80A, 80B, on a plane perpendicular to the optical axis direction L, two types of two products Two LED arrays 75A, 75B are arranged. In addition, one of two second LED arrays 75A, 75A and the other two second LED arrays 75B, 75B are alternately arranged at intervals of 90° on the plane.

For example, the 1st LED array 71 uses the LED element 72 whose peak wavelength is 365 nm, and one 2nd LED array 75A is the LED element 76A whose peak wavelength is 385 nm. , and the other second LED array 75B uses an LED element 76B having a peak wavelength of 330 nm. And when using the 1st LED array 71 and one 2nd LED array 75A, and when using the 1st LED array 71 and the other 2nd LED array 75B, it is different The two types of dichroic mirrors 80 and 90 are switched and used. Accordingly, the dichroic mirrors 80 and 90 are disposed so as to be detachably attached to a mirror mounting portion (not shown) by changing the mounting posture.

Further, the dichroic mirror 90 is constituted by two dichroic mirrors 90A and 90B, similarly to the dichroic mirror 80 described in the first to third embodiments. However, in the present embodiment, the dichroic mirrors 80 and 90 have different characteristics of reflecting the wavelength band of the characteristics according to the two second LED elements 76A and 76B.

When the use of the second LED arrays 75A, 75B is switched, the dichroic mirror 80 when the first LED array 71 and one of the second LED arrays 75A are used, and the first LED array The dichroic mirror 90 when 71 and the other second LED array 75B are used is such that the alignment directions of the dichroic mirrors 80A, 80B, 90A, 90B are orthogonal to each other on the plane. will be placed

Accordingly, when the light source device switches the two types of second LED elements 76A, 76B to a specification capable of exposure, only the dichroic mirrors 80 and 90 are replaced, and the second LED array 75A .

Moreover, as a modification of this embodiment, when the peak wavelengths of two types of 2nd LED arrays 75A, 75B are the same, it is good also considering the dichroic mirror 80 as a rotatable structure. And when using the LED arrays 75A, 75B, respectively, the direction of the dichroic mirror 80 is rotated according to the LED arrays 75A, 75B to be used.

In addition, this invention is not limited to each embodiment mentioned above, A deformation|transformation, improvement, etc. are possible suitably.

For example, in the above embodiment, light having different peak wavelengths is synthesized by a dichroic mirror. However, the optical synthesis element of the present invention is not limited to this and may be a dichroic prism.

As shown in Fig. 10, the dichroic prism 180 is a combination of three right-angle prisms 181, 182, 183, which are materials having high transmittance, such as glass or plastic. Each of the prisms 181 , 182 , 183 has a substantially right isosceles triangular shape when viewed from the side, and the prism 181 is larger than the prisms 182 and 183 . The dichroic prism 180 has a rectangular shape when viewed from the side, in which sides other than the oblique side of the prism 181 and the oblique sides of the prisms 182 and 183 are joined through a dichroic film (not shown). have a shape In addition, the interface 184 of the prisms 181 and 182 on which the dichroic film is disposed, and the interface 185 of the prisms 181 and 183 are inclined at approximately 45 degrees with respect to the optical axis direction L, 2 The interfaces 184 and 185 are formed to intersect at 90°. Accordingly, the two dichroic films are arranged in a substantially V-shape so as to be in close contact with the fly's eye lens side.

The dichroic prism 180 has the interface (181a, 182a, 182b, 183a, 183b, 184, 185) (light incident surface and light output surface) of light from the 1st LED array 71 and the 2nd LED array 75. Including ) can be made the same number of times through. In addition, by using the dichroic prism 180, the structure for bringing the two dichroic mirrors into close contact becomes unnecessary.

Further, in the above embodiment, the light emitted from the two LED arrays is emitted to the fly's eye lens 65 through the dichroic mirror using the dichroic mirrors arranged in a V shape. On the other hand, as another optical device 70A of the present invention, as shown in Fig. 11, it does not have the dichroic mirrors 80A, 80B, but is composed of only one LED array 78, and the LED array 78 The false fly's eye lens 65 may be disposed directly opposite the fly's eye lens 65 .

In this case, in the LED array 78, the 1st LED element 72 and the 2nd LED element 76 are mixed and are arrange|positioned. Accordingly, the light emitted from the LED array 78 is emitted to the fly's eye lens 65 by mixing the light from the first LED element 72 and the light from the second LED element 76 .

The peak wavelength of the light irradiated from the second LED element 76 is any wavelength of 300 to 355 nm in accordance with the peak wavelength (photosensitive wavelength) of the polymerization initiator of the photosensitive material, and the first LED element 72 The peak wavelength of light irradiated from ) is set to any wavelength in the range of 360 to 380 nm by matching the sensitivity to the portion below the absorption of the polymerization initiator. Specifically, the peak wavelength of the light irradiated from the second LED element 76 is set to, for example, 335 nm, and the peak wavelength of the light irradiated from the first LED element 72 is, for example, 365 nm. is set to

In this way, the resist can be photosensitized efficiently, a photosynthesis element such as a dichroic mirror for synthesizing light becomes unnecessary, and the LED array 78 can be placed close to the fly's eye lens 65 . can, the efficiency is improved. Moreover, the restriction|limiting which separates the wavelength of the light of the 1st and 2nd LED element 72, 76 by 20 nm or more is also unnecessary, and a peak wavelength can be set freely according to the sensitivity of a photosensitive material.

Further, as in another modified example shown in FIG. 12 , the light source device 70B includes a single dichroic mirror 80 instead of the two dichroic mirrors 80A and 80B arranged in a V shape. may be configured as In this case, the first LED array 71 having the plurality of first LED elements 72 and the second LED array 75 having the plurality of second LED elements 76 are orthogonally arranged, and the dichroic mirror 80 is disposed at an angle of 45° with respect to the first LED array 71 and the second LED array 75 .

Accordingly, the light irradiated from the first LED array 71 passes through the dichroic mirror 80 and enters the fly's eye lens 65, and the light irradiated from the second LED array 75 is dichroic. The light reflected by the loic mirror 80 is combined with the light irradiated from the first LED array 71 and is incident on the fly's eye lens 65 .

In addition, although a color filter resist is manufactured by mixing a polymerization initiator, a pigment, a polymerizable monomer, a polymer, and a solvent, As a polymerization initiator which has an absorption peak in the range of 300-355 nm, the following (1)-(10) can be heard of Among these polymerization initiators, (9) Irgacure OXE01, and (10) Irgacure OXE02, which are highly sensitive, are preferable.

(1) Name: Omnirad184 (registered trademark), manufactured by IGM Resins B.V. (1-hydroxycyclohexyl-phenyl ketone)

[Formula 1]

(2) Name: Omnirad1173 (registered trademark), manufactured by IGM Resins B.V. (2-hydroxy-2-methyl-1-phenylpropanone)

[Formula 2]

(3) Name: Omnirad651 (registered trademark), manufactured by IGM Resins B.V. (2,2-dimethoxy-2-phenylacetophenone)

[Formula 3]

(4) Name: Omnirad2959 (registered trademark), manufactured by IGM Resins B.V. (1-[4-(2-hydroxyethoxyl)-phenyl]-2-hydroxy-methylpropanone)

[Formula 4]

(5) Name: Omnirad127 (registered trademark), manufactured by IGM Resins BV (2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropionyl)benzyl)phenyl)-2-methylpropan-1-one )

[Formula 5]

(6) Name: Omnirad369 (registered trademark), manufactured by IGM Resins B.V. (2-benzyl-2-(dimethylamino)-4'-morpholinobutyrophenone)

[Formula 6]

(7) Name: Omnirad379EG (registered trademark), manufactured by IGM Resins BV (2-dimethylamino-2-(4-methyl-benzyl)-1-(4-morpholin-4-yl-phenyl)-butan-1-one )

[Formula 7]

(8) Name: Omnirad MBF (registered trademark), manufactured by IGM Resins B.V. (Methylbenzoylformate)

[Formula 8]

(9) Name: Irgacure OXE01 (registered trademark), manufactured by BASF Japan Co., Ltd. (1,2-Octanedione, 1-[4-(phenylthio) phenyl]-, 2-(o-benzoyloxime)

[Formula 9]

(10) Name: Irgacure OXE02 (registered trademark), manufactured by BASF Japan Co., Ltd. (Ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-, 1-(O-acetyloxime) )

[Formula 10]

In addition, this application is based on the JP Patent application (Japanese Patent Application No. 2019-038939) of an application on March 4, 2019, The content is taken in as a reference during this application.

65: fly eye lens
70, 70A, 70B: light source device
71: first LED array
72: first LED element
75, 75A, 75B: 2nd LED Array
76, 76A, 76B: second LED element
78: LED array (light source device)
80, 80A, 80B: Photosynthetic device (dichroic mirror)
81: dichroic membrane
83: end
85: dichroic mirror fixed frame
180: Photosynthesis element (dichroic prism)
M: mask
PE: proximity exposure device
W: Work (substrate)
L1: length of the first LED array
L2: length of the second LED array

Claims (14)

a first LED array having a plurality of first LED elements emitting light of a first peak wavelength;
a second LED array having a plurality of second LED elements emitting light of a second peak wavelength different from the first peak wavelength;
a light synthesizing element for synthesizing the light of the first and second LED arrays;
a fly-eye lens into which the light synthesized by the optical synthesis element is incident;
A light source device for exposure comprising:
The optical synthesis element includes two dichroic films that transmit light in a specific wavelength band and reflect light in other wavelength bands, and the two dichroic films form the fly's eye lens from the optical synthesis element. is inclined with respect to the optical axis direction toward
The first LED array is disposed on the opposite side of the fly's eye lens with respect to the optical synthesis element in the optical axis direction,
and the second LED array intersects the optical axis direction and is disposed on the side of the optical synthesis element. The method of claim 1,
A peak wavelength of light irradiated from either one of the first LED element and the second LED element is 360 to 380 nm,
The peak wavelength of the light irradiated from the other of the said 1st LED element and the said 2nd LED element is 300-355 nm or 385-410 nm,
The light source device for exposure, wherein the peak wavelengths of the first LED element and the second LED element are separated by 20 nm or more. 3. The method according to claim 1 or 2,
The length of the second LED array disposed on the side of the optical synthesis device is,
The light source device for exposure, which is shorter than the length of the first LED array disposed on the opposite side of the fly's eye lens with respect to the optical synthesis element. 4. The method according to any one of claims 1 to 3,
The light source device for exposure, wherein the optical synthesis element is a dichroic mirror or a dichroic prism of two sheets. The method of claim 1,
The optical synthesis element is two dichroic mirrors each having the dichroic film,
and an end portion of each of the dichroic mirrors is cut parallel to the optical axis direction. 6. The method of claim 5,
and two dichroic mirror fixing frames each fixed to the dichroic mirror and open on a side where the two dichroic mirrors are in close contact with each other;
and a tip end of the dichroic mirror fixing frame on the fly's eye lens side is cut at a right angle to the optical axis direction. 7. The method according to any one of claims 1 to 6,
The light source device for exposure, wherein the second LED array has two types of second LED arrays alternately arranged at intervals of 90° on a plane orthogonal to the optical axis direction. A lighting device comprising the light source device for exposure according to any one of claims 1 to 7;
a work support for supporting the work;
a mask support for supporting the mask;
An exposure apparatus comprising: irradiating light irradiated from the illumination device to the work through the mask to transfer the pattern of the mask onto the work. The exposure method of irradiating the light irradiated from the said illumination device to the said workpiece|work through the said mask using the exposure apparatus of Claim 8, and transferring the pattern of the said mask to the said workpiece|work. A plurality of first LED elements emitting light of a first peak wavelength in the range of 360 to 380 nm, corresponding to the photosensitive wavelength of the polymerization initiator of the photosensitive material formed on the substrate, and a second peak wavelength in the range of 300 to 355 nm a plurality of second LED elements emitting light of
to provide
The light of the first LED element and the light of the second LED element are mixed and emitted to the fly's eye lens, the light source device for exposure. 11. The method of claim 10,
and an LED array in which the first LED element and the second LED element are disposed to be mixed. 11. The method of claim 10,
a first LED array having the plurality of first LED elements;
a second LED array having the plurality of second LED elements;
a light synthesizing element for synthesizing the light of the first and second LED arrays;
to provide
In the optical synthesis device, a dichroic film that transmits light in a specific wavelength band and reflects light in other wavelength bands is disposed inclined with respect to an optical axis direction from the optical synthesis device toward the fly's eye lens,
Either one of the first LED array and the second LED array is disposed on the opposite side of the fly's eye lens with respect to the optical synthesis element in the optical axis direction,
The light source device for exposure, wherein the other of the first LED array and the second LED array intersects the optical axis direction and is disposed on the side of the optical synthesis element. A lighting device comprising the light source device for exposure according to any one of claims 10 to 12;
a work support for supporting the work;
a mask support for supporting the mask;
An exposure apparatus comprising: irradiating light irradiated from the illumination device to the work through the mask to transfer the pattern of the mask onto the work. An exposure method in which a pattern of the mask is transferred to the work by irradiating the light irradiated from the illuminating device to the work through the mask using the exposure apparatus according to claim 13 .

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