JP2003218017A - Laser lighting optical system, aligner using the same, laser processing device, and projection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laser lighting optical system which is equipped with a laser array light source and fly's-eye lens and capable of improving an irradiated part in illuminance uniformity, even in a case in which an irradiated part is hard to be improved in illuminance uniformity when the number of divides of the split fly's-eye lens is the divisor of the number of laser arrays. <P>SOLUTION: This laser lighting optical system is composed of, at least, a laser array light source 10 and a fly's-eye lens integrator in vehicle the number of divides of the fly's-eye lenses 13 and 14 is the divisor of the number of laser arrays in the direction of the laser array. Light of the laser array light source 10 impinging on each lens of the fly's-eye lenses 13 and 14 is different from each other in phase in profile, the periodic structure of the laser arrays and the size of the fly's-eye lenses are determined under the prescribed condition, so that an irradiated part 16 can be set uniform in illuminance even under the condition that the number of divisions of the fly's-eye lenses is the divisor of the number of laser arrays. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser illumination optical system using a laser as a light source to uniformize the illuminance in an irradiated portion, an exposure apparatus, a laser processing apparatus and a projection apparatus using the same.

[0002]

2. Description of the Related Art A projection device using a laser as a light source is expected to have high color purity because the oscillation spectrum of the laser is narrow. On the other hand, since the laser has a high coherence, an interference fringe may occur when the light fluxes are divided and then combined. For example, when the illuminance of one laser beam is made uniform by a normal fly-eye lens optical system, interference fringes are seen in the irradiated portion. Further, for example, in the hologram element described in Japanese Patent Application Laid-Open No. 8-94839, a part of the laser beam is superposed on the irradiated portion, and a structure for suppressing interference is disclosed. Does not go away.

On the other hand, a laser array light source (particularly a semiconductor laser array light source) is expected as a laser light source having a relatively small size and a high light output. By combining this laser array light source with a fly-eye lens, the illuminance at the irradiated portion is increased. It is possible to configure a laser illumination optical system in which Further, when the laser array light source and the fly-eye lens are combined, the illuminance can be made uniform by selecting the number of divisions of the fly-eye lens other than a divisor of the number of laser arrays.

However, if a number other than a divisor of the number of laser arrays is selected as the number of divisions of the fly-eye lens, the number may be large depending on the number of laser arrays, and the degree of freedom in design is low. There was a problem. That is, when combining a laser array light source and a fly-eye lens, if the illuminance can be made uniform by a division number that is a divisor of the number of laser arrays as the division number of the fly-eye lens, the degree of freedom in designing the laser illumination optical system is increased. Can be higher.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides a laser illumination optical system in which a laser array light source and a fly-eye lens are combined.
It is an object of the present invention to improve the illuminance uniformity in the irradiated portion when the number of divisions of the fly-eye lens, which has been difficult to make the illuminance uniform in the past, is a divisor of the number of laser arrays.

More specifically, the invention according to claims 1, 2, and 3 has a laser array light source and a fly-eye lens, and the number of divisions of the fly-eye lens, which has been difficult to make the illuminance uniform in the past, is turned on. An object of the present invention is to provide a laser illuminating optical system capable of enhancing the illuminance uniformity in the irradiated area even when the number of existing laser arrays is a subdivision. Further, the invention according to claim 4 has a semiconductor laser array light source and a fly-eye lens, and the number of divisions of the fly-eye lens, which has been difficult to make the illuminance uniform in the past, is about the same as the number of lit laser arrays. At the same time, it is an object of the present invention to provide a laser illumination optical system capable of increasing the illuminance uniformity in the laser array direction at the irradiated portion.

Further, in the invention according to claim 5, even when the number of divisions of the fly-eye lens, which has been difficult to make the illuminance uniform in the past, is a divisor of the number of laser arrays, the illuminance becomes uniform in the laser array direction in the irradiated portion. It is an object of the present invention to provide a laser illuminating optical system that can improve the illuminance to the irradiated portion by reducing the interference fringes caused by the light flux in the array vertical direction of the laser array light source. To do. Also,
In the invention according to claim 6, a hologram element is used instead of the fly-eye lens, and even when the number of divisions is a divisor of the number of laser arrays, it is possible to enhance the illuminance uniformity in the laser array direction in the irradiated portion. Provided is a laser illumination optical system capable of reducing interference fringes caused by a light flux of a laser array light source in a direction perpendicular to an array, improving illumination performance on an irradiated portion, and further miniaturizing an optical system. The purpose is to

It is an object of the present invention to provide an exposure apparatus in which the illumination optical system has a uniform illuminance and which has a good illumination performance for a reticle or the like. It is another object of the present invention to provide a laser processing device in which the illumination optical system has a uniform illuminance and high illuminance uniformity, and further a laser processing device having no interference fringes. Further, the invention according to claim 9 is to provide a projection device in which the illuminance of the illumination optical system is uniform and the illumination performance on the spatial modulator (light valve) is good, and further a projection device in which no interference fringes occur. And
In addition to the object of claim 9, it is an object of the invention according to claim 10 to provide a projection device capable of reducing the size of the illumination optical system.

[0009]

In order to achieve the above object, in the laser illumination optical system according to claim 1, at least the laser array light source and the number of divisions of the fly-eye lens in the laser array direction are divisors of the number of laser arrays. A laser illumination optical system composed of a fly eye integrator,
It is characterized in that the spatial phase of the profile of the array light incident on each array of the fly-eye lens is different. A laser illuminating optical system according to claim 2 is a laser illuminating optical system including a laser array light source and a fly-eye lens integrator that are periodically arranged, and the laser array light source is periodically arranged. It is characterized in that it is provided with a non-light emitting light emitting section, and the number of divisions of the fly-eye lens in the laser array direction is a divisor of the number of laser arrays to be turned on. In addition to the configuration of claim 1 or 2, the laser illumination optical system according to claim 3 has
It is characterized by comprising means arranged between the laser array light source and the fly-eye lens and displacing the laser array light incident on each array of the fly-eye lens by a predetermined distance.

According to a fourth aspect of the present invention, there is provided a laser illumination optical system in which a semiconductor laser array light source, a collimating lens array, and a fly-eye lens are divided in the laser array direction so that the number of divisions of the fly-eye lens is a divisor of the number of lit laser arrays. It is characterized in that it has an integrator and a means arranged between the collimator lens array and the fly-eye lens to displace the laser array light incident on each array of the fly-eye lens by a predetermined distance.

According to a fifth aspect of the present invention, in the laser illumination optical system according to the first, third or fourth aspect, the fly-eye integrator is composed of a cylindrical lens array and a cylinder lens, and a light flux in a direction orthogonal to the laser array is
It is characterized by being made uniform by a hologram element having a modulation pitch arranged between the light source and the fly-eye integrator. Further, in the laser illumination optical system according to claim 6, in the configuration according to claim 1, 3 or 4, the fly-eye integrator is configured by a hologram element having the same function instead of the fly-eye lens, and is orthogonal to the laser array. Is characterized by being made uniform by a hologram element having a modulation pitch arranged between the light source and the fly-eye integrator.

An exposure apparatus according to claim 7 is the exposure apparatus according to any one of claims 1 to 6.
The laser illuminating optical system according to any one of the above 1 and the projection lens is provided. Further, a laser processing apparatus according to claim 8 is characterized by including the laser illumination optical system according to any one of claims 1 to 6 and a lens.

A projection device according to a ninth aspect is the projection device according to the first to sixth aspects.
The laser illumination optical system according to any one of the above items, a color synthesizing unit, a spatial modulator (light valve), and a projection lens are provided. A projection apparatus according to a tenth aspect of the invention is characterized in that, in addition to the configuration of the ninth aspect, a fly eye integrator is arranged between the color synthesizing means and the spatial modulator.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The configuration, operation and action of a laser illumination optical system according to the present invention and an exposure apparatus, laser processing apparatus and projection apparatus using the same will be described in detail below with reference to the embodiments shown in the drawings. .

(Embodiment 1) First, an embodiment of the invention according to claim 1 will be described. FIG. 1 is a schematic plan configuration diagram of a laser illumination optical system showing an embodiment of the invention according to claim 1. This laser illumination optical system includes a laser array light source 10 in which a plurality of light emitting parts are arranged in an array, a first fly-eye lens 13, a second fly-eye lens 14, and a condenser lens 15, It is configured with a fly-eye integrator whose number of divisions in the laser array direction is a divisor of the number of laser arrays, and a plurality of laser beams oscillated from the laser array light source 10 are irradiated via the fly-eye integrators 13 to 15. 16
Illuminate. The irradiated portion 16 is a portion to which a uniform light flux is irradiated, and an exposure mask (reticle) in the exposure apparatus corresponds to the spatial light modulator (so-called light valve) in the projection apparatus. .

As the laser array light source 10, it is possible to preferably use a type in which laser oscillation parts (light emitting parts) such as a semiconductor laser are arranged in an array or a stripe type laser. A first fly-eye lens 13 and a second fly-eye lens 14 which constitute a fly-eye integrator.
Is an array of spherical or cylindrical lenses arranged in the same direction as the direction of the laser array. For example, the first fly-eye lens 13 splits the incident light flux into light fluxes of the number of lens arrays. In addition, the second fly-eye lens 14 has a function of focusing light on each lens. The second fly-eye lens 14 refracts the image condensed by the first fly-eye lens and collects the light flux on the irradiated portion 16 as much as possible.

The condenser lens 15 arranged on the light path on the emission side of the second fly-eye lens 14 of the fly-eye integrator is composed of, for example, a cylindrical lens, and the condenser lens 15 is disposed at a predetermined position on the irradiated portion 16. Is provided for more uniform illumination, and by concentrating the light emitted from the second fly-eye lens 14 onto the irradiated portion 16, the light utilization efficiency can be increased and the illuminance can be increased. It is intended to eliminate the unevenness and improve the uniformity. That is, the light intensity in the lens array direction is made uniform by the first and second fly-eye lenses 13 and 14, but without the condenser lens 15, array light that does not illuminate the irradiated portion 16 is generated. The illuminance unevenness may occur depending on how the array lights are overlapped in the irradiated portion 16, but in the present embodiment, the condenser lens (cylindrical lens) 15 is used for the first and second fly-eye lenses 13. , 14 are set so that the light beams in the lens array direction (laser array direction) are condensed on the irradiated portion 16, so that uniform irradiation in the irradiated portion 16 is realized.

In the present embodiment, the number of divisions of the fly-eye lenses 13 and 14 constituting the fly-eye integrator in the laser array direction is a divisor of the number of arrays of the laser oscillation section (light emitting section) of the laser array light source 10. . In the example of FIG. 1, the number of laser arrays is 16, and the number of divisions of the fly-eye lenses 13 and 14 in the laser array direction is 4. Note that this is an example, and other combinations may be used as long as a divisor relationship is established. Further, in this embodiment, the fly-eye lens 1
It is characterized in that the spatial phase of the profile of the laser array light incident on each of the arrays 3 and 14 (each lens portion) is different.

Here, the relationship between the arrangement of the light emitting portions of the laser array light source 10 and the fly-eye lenses 13 and 14 will be described with reference to FIG. FIG. 3 shows a profile of the laser array light incident on the first fly-eye lens 13 of the laser illumination optical system shown in FIG. The laser light from each light emitting portion of the laser array light source 10 is periodically arranged in fours with a beam diameter of P in a Gaussian profile, and the next four are arranged with a gap of P. In other words, 5
There will be 4 laser profiles in the P period. Therefore, the length of each array (each lens portion) of the first fly-eye lens 13 is set to 19P / 4. With such a configuration, the profile of the laser light incident on the first fly-eye lens 13 is out of phase by P / 4. Since the first fly-eye lens 13 and the irradiated portion 16 have a conjugate relationship, the irradiated portion 16 is also shifted in phase by P / 4 and the Gaussian profile array is added. The intensity distribution of the laser array light (arrays 1 to 4) that has passed through the four-divided arrays (lens portions) of the fly-eye lens and the intensity distribution added on the irradiated portion 16 are as shown in FIG. The illumination intensity on the irradiated portion 16 is made uniform.

(Embodiment 2) Next, an embodiment of the invention according to claim 2 will be described. FIG. 2 is a schematic plan configuration diagram of a laser illumination optical system showing an embodiment of the invention according to claim 2. This laser illumination optical system includes a laser array light source 11 in which a plurality of light emitting parts are arranged in an array, a first fly-eye lens 13, a second fly-eye lens 14, and a condenser lens 15. However, the laser array light source 11
Unlike in the first embodiment, the light source is driven so that there is a light emitting unit that does not turn on periodically, although the distances from the adjacent lasers are all the same. That is, the laser array light source 11 is provided with the non-light-emitting part periodically arranged. In FIG. 2, as an example, the five light emitting units 11a to 11a of the laser array light source 11
One set of 11e is set as one set, and one of the light emitting units 11e is turned off. The fly-eye lenses 13 and 14 are configured so that the number of divisions in the laser array direction is a divisor of the number of laser arrays to be turned on.
The irradiated portion 16 is illuminated with a plurality of laser beams emitted by the fly eye integrators 13 to 15.
The irradiated portion 16 is a portion to which a uniform light beam is irradiated, and an exposure mask (reticle) in the exposure apparatus corresponds to the spatial light modulator (so-called light valve) in the projection apparatus. . As the laser array light source 11, it is possible to preferably use a type in which laser oscillation parts (light emitting parts) such as lasers are arranged in an array or a stripe type laser. The function of the fly-eye integrator is the same as that described in the first embodiment, and thus the description thereof is omitted.

In the present embodiment, the laser light emitted by the laser array light source 11 is periodically arranged in fours with a beam diameter of P according to a Gaussian profile, and the next four are arranged with a gap of P. It In other words, there are four laser profiles within a period of 5P. Therefore, as shown in FIG. 3, the length of each array (each lens portion) of the first fly-eye lens 13 is set to 19P / 4. With such a configuration, the first fly-eye lens 1
The phase of the laser light entering 3 is shifted by P / 4. Since the first fly-eye lens 13 and the irradiated portion 16 have a conjugate relationship, the irradiated portion 16 also has a P
The Gaussian profile arrays are added with a phase shift of / 4. Laser array light (array 1 to array 1) that has passed through each of the four divided arrays (each lens section) of the fly-eye lens
The intensity distribution of 4) and the intensity distribution added on the irradiated portion 16 are as shown in FIG. 6, and the illumination intensity on the irradiated portion 16 is made uniform.

(Embodiment 3) Next, an embodiment of the invention according to claim 3 will be described. FIG. 4 is a schematic plan configuration diagram of a laser illumination optical system showing a first embodiment of the invention according to claim 3. This laser illumination optical system includes a laser array light source 11
And a plurality of parallel flat plates 12a, 12c, 12d and fly-eye integrators 13, 14, 15 and 16 denotes an irradiated portion. That is, in addition to the configuration of FIG. 1, the configuration shown in FIG.
And the fly-eye integrators 13, 14, 15 between the plurality of parallel plates 12a, 12c, 12d made of transparent members.
And a means for displacing the laser array light incident on each of the arrays of the fly-eye lenses 13 and 14 by a predetermined distance by a plurality of parallel plates 12a, 12c and 12d. The fly-eye integrators 13 and 1
The configurations and functions (operations) of Nos. 4 and 15 are similar to those of the first embodiment.

In this embodiment, the number of laser arrays of the laser array light source 11 is 16 as in the first embodiment (FIG. 1), and the first and second fly-eye lenses 13 and 14 are arranged in the laser array direction for the purpose of explaining the operation. The number of divisions of is set to 4. The first fly-eye lens 1 when configured with a normal fly-eye integrator 1
Four laser array lights having a profile (intensity distribution) as shown in FIG. 5 are incident on one array (lens part) 3 of FIG. Since light having the same profile as that in FIG. 5 is incident on all the arrays (lens parts) of the first fly-eye lens 13, four profiles in FIG. 5 are integrated in the irradiated part 16 in the same phase, Illuminance unevenness occurs.

Therefore, in this embodiment, as shown in FIG. 4, a plurality of parallel flat plates 12a, 12c, 12d are arranged between the laser array light source 11 and the first fly-eye lens 13, and each array of fly-eye lenses 13 is arranged. A means for displacing the incident laser array light by a predetermined distance is provided. The parallel plates 12a, 12c,
12d is arranged at a predetermined inclination angle and has a predetermined thickness. For example, one beam diameter P of laser array light
Is 1 mm, the number of divisions of the fly-eye lens 13 is 4
Therefore, the displacement amount of light by the parallel plates 12a, 12c, and 12d is set to ¼ = 0.25 [mm] each. As a specific example, parallel flat plates 12a, 12c and 12d having inclination angles and thicknesses as shown in Table 1 below are arranged. However,
The refractive indexes of the parallel flat plates 12a, 12c, 12d were set to 1.52.

[0025]

[Table 1]

In Table 1, the parallel plates 12a, 12c, 1
Although the displacement amount is determined by the inclination direction and thickness of 2d, the inclination angles may be changed by making the thicknesses of the parallel flat plates 12a, 12c, 12d the same as shown in Table 2 below.

[0027]

[Table 2]

The parallel plate 12a, 12c, 12d having the inclination angle and the thickness shown in Table 1 or Table 2 is used to displace the optical path of the laser array light, and the fly-eye integrators 13, 1 are arranged.
When the irradiated portion 16 is illuminated with 4 and 15, the intensity distribution as shown in FIG. 6 is obtained. That is, the incident light profile to each array (each lens part) of the first fly-eye lens 13 is shown in FIG.
Since the intensity distributions are out of phase as shown in arrays 1 to 4 above, the illuminance becomes uniform when integrated in the irradiated portion 16. However, since the peripheral portion of the combined light is not uniform, the uniformity can be secured by designing the area shown by the arrow in FIG. 6 to be the irradiated portion.

Next, FIG. 7 is a schematic plan view of a laser illumination optical system showing a second embodiment of the invention according to claim 3.
This laser illumination optical system is composed of a laser array light source 11, a plurality of hologram elements 41a, 41c and 41d, and fly-eye integrators 13, 14 and 15, and 16 indicates an irradiated portion. That is, in the configuration shown in FIG. 7, instead of the parallel plate of the configuration shown in FIG. 4, the laser array light source 11 and the fly eye integrators 13, 14,
A plurality of hologram elements 41a, 41c, 41 between 15
a plurality of hologram elements 41a, 41c, 4
1d is a means for displacing the laser array light incident on each array of the fly-eye lenses 13 and 14 by a predetermined distance. The other configurations are the same as those in FIG.

Hologram elements 41a, 41c, 41d
Is a structure in which, for example, relief-type holograms are formed on the front and back of a transparent parallel plate, and the light diffracted on the front side is diffracted again by the hologram on the back side. In addition, the hologram element 41
The incident optical axis and the outgoing optical axis to a, 41c, and 41d are made parallel, and the displacement amount is the same as the value shown in the first embodiment. Even with the configuration of the second embodiment, the illuminance distribution in the irradiated portion 16 is as shown in FIG. 6, and the illuminance is made uniform. In this embodiment, holograms are installed on the front and back sides of hologram elements 41a, 41c, and 41d, but the effect of the present invention can be obtained without making the incident optical axis and the outgoing optical axis parallel. Therefore,
The hologram element may have a hologram formed on one of the front and back sides.

(Embodiment 4) Next, an embodiment of the invention according to claim 4 will be described. FIG. 8 is a schematic plan view of a laser illumination optical system showing an embodiment of the invention according to claim 4. This laser illumination optical system outputs a laser array light source 51 (for example, a semiconductor laser array light source) in which laser light emitting portions are arranged in an array, a collimator lens array 52, and laser array light incident on each array of fly-eye lenses. It is composed of a means 12 for displacing a predetermined distance and fly-eye integrators 13, 14 and 15.
6 is an irradiated part.

Fly-eye integrators 13, 14, 1
The configuration and function (operation) of 5 are similar to those of the first embodiment. As the displacing means 12, as an example, a case where a plurality of parallel flat plates 12a, 12c, 12d are used as in the first embodiment of the third embodiment is shown, but in addition, a second embodiment of the third embodiment is used. The displacement means using a plurality of hologram elements similar to the example may be used. Each laser beam emitted from the laser array light source 51 is diverged at a divergence angle of about 10 to 30 ° in all angles. The collimating lens array 52 functions to collimate these divergent beams. That is, in the collimator lens array 52, the lenses are arrayed at the same pitch as the array pitch of the light emitting portions of the laser array light source 51, and the laser light emitted from each light emitting portion of the laser array light source 51 corresponds to the corresponding lens. Collimate with to make parallel light flux. The laser beam collimated by the collimator lens array 52 is displaced by the displacement means 12 by a predetermined distance.

If the number of arrays of the laser array light source 51 is 16 and the number of divisions of the first and second fly-eye lenses 13 and 14 in the light source array direction is 4, the first fly-eye lens 13 is divided. Array light of four Gaussian profiles similar to those in FIG. 5 is incident on each array. Therefore, at this time, the displacement means 12 (for example, the plurality of parallel flat plates 12a, 1
2c and 12d) are as shown in Table 1 or Table 2 above, and as described in Example 3, the incident light profile to each array (each lens portion) of the first fly-eye lens 13 is as shown in FIG. Since the intensity distributions are out of phase as shown in Arrays 1 to 4 of No. 6, the illuminance is uniformized when integrated in the irradiated portion 16. In this way, even if the light source 51 is a laser array, the fly-eye lens 13, by using the collimating lens array 52 and the displacement means 12,
Even under the condition that the number of divisions of 14 is a divisor of the number of arrays of light sources, the illuminance on the irradiated portion 16 can be made uniform.

(Embodiment 5) Next, an embodiment of the invention according to claim 5 will be described. 9A and 9B are views showing an embodiment of the invention according to claim 5, wherein FIG. 9A is a schematic plan view of the laser illumination optical system, and FIG. 9B is a schematic side view of the laser illumination optical system. This laser illumination optical system includes a laser array light source 51 (for example, a semiconductor laser array light source) in which laser light emitting portions are arranged in an array, a collimator lens array 52, and a means 12 for displacing the laser array light by a predetermined distance. A hologram element 61 for uniformizing a light beam in a direction orthogonal to a laser array, and a fly-eye integrator 6
3, 64 and 65, and 16 is an irradiated portion. Although the collimating lens array 52 is shown in FIGS. 9A and 9B, it is not always necessary if the spread angle of the light source is small. Further, the displacement means 12 is, for example, a plurality of parallel flat plates 12a, 1 similar to the first embodiment of the third embodiment.
Although the case where 2c and 12d are used is shown in the figure, it is also possible to use a hologram element similar to the second embodiment of the third embodiment.

The fly-eye integrator of this embodiment is composed of fly-eye lenses 63 and 64 and a condenser lens 65, and is composed of a cylindrical lens system as in the first embodiment and has the same function. That is, the first and second fly-eye lenses 63 and 64 are cylindrical lens arrays, and the condenser lens 65 is a cylindrical lens. Then, the light flux parallel to the plane of the paper of FIG. 9A is made uniform by the fly-eye integrator, and the irradiated portion 16 is uniformly illuminated. The operation on the paper surface of FIG. 9A is the same as the operation described in the fourth embodiment, and the laser array light incident on the first fly-eye lens 63 is displaced by the displacing means 12.
Is displaced by a predetermined distance and the phase of the profile irradiated on the irradiated portion 16 is appropriately shifted, so that the illuminance is made uniform.

Next, the hologram element 61 for making the light flux in the orthogonal direction uniform in the laser array will be described. The hologram element 61 is composed of a transmission type amplitude grating, a transmission type phase grating, a transmission type blazed grating, or the like. The hologram element 61 is printed with interference fringes on a photoresist, or a groove is mechanically formed on a substrate surface such as a glass plate with a diamond cutter. It can be produced by drawing lines. This hologram element 61 is
It has a function of converting the intensity distribution in only one direction (the pitch direction of the grating grooves) of the laser light flux emitted from the laser array light source 51 by the grating. In this embodiment, since the grating direction of the hologram element 61 is parallel to the paper surface of FIG. 9A and the grating pitch is different within the hologram element surface, it functions to make the laser array uniform the light flux in the orthogonal direction. To do. The modulation pitch of this hologram element 61 is
As an example, it is realized with a lattice pitch as shown in FIG. When a laser beam having a Gaussian profile is incident on such a modulation pitch, the vicinity of the center of the light beam expands, and the periphery of the beam is compressed, resulting in uniform intensity. Figure 9
In (b), the light beams with high intensity are shown with a narrow interval, and the hologram array 61 allows the laser array light source 5 to emit light.
The direction of the light ray in the direction orthogonal to the laser array of No. 1 is changed, and uniform illuminance is obtained at the irradiated portion 16. Since the fly-eye integrators 63, 64, 65 are composed of a cylindrical lens system, as shown in FIG. 9 (b),
When the fly-eye integrator is viewed from the side of the illumination optical system, it is merely a flat plate, and there is no refracting action of the laser array light source 51 in the direction orthogonal to the laser array.

In the process of uniformizing the illuminance of the light flux in the direction orthogonal to the laser array by the hologram element 61, the interference fringes are generated even when the light flux is split using the fly-eye integrators 63, 64 and 65 and superposed by the irradiated portion 16. Occurrence does not occur. That is, since the hologram element 61 continuously changes the density (illuminance) of the light flux, no interference fringes appear. Therefore, the illuminance uniformity of the irradiated portion 16 becomes good. Although the optical system using the fly-eye integrators 63, 64, and 65 is shown in FIG. 9A, the laser array light source 5 is used as the light to be superposed on the irradiated portion 16.
Since the light is emitted from one separate optical resonance part (laser emission part), it does not interfere.

(Embodiment 6) Next, an embodiment of the invention according to claim 6 will be described. 11A and 11B are views showing an embodiment of the invention according to claim 6, wherein FIG. 11A is a schematic plan configuration diagram of a laser illumination optical system, and FIG. 11B is a schematic side configuration diagram of the laser illumination optical system. This laser illumination optical system includes a laser array light source 51 (for example, a semiconductor laser array light source) in which laser light emitting portions are arranged in an array, a collimator lens array 52, and a means 12 for displacing the laser array light by a predetermined distance. A hologram element 61 for uniformizing a light beam in a direction orthogonal to the laser array and a hologram element 62 having a fly-eye integrator function are provided.
Is an irradiated part.

The laser illumination optical system of this embodiment is replaced with the fly-eye integrator (fly-eye lens and condenser lens) of the laser illumination optical system having the configuration shown in FIG.
A hologram element 62 having the same function as that of the fly-eye integrator is used, and other laser array light source 51, collimator lens array 52, and displacement means 1 are used.
2. The configuration and operation of the hologram element 61 are the same as those in the fifth embodiment, and therefore their description will be omitted.

Since the hologram element 62 as a fly-eye integrator has the same function as the fly-eye lens system shown in FIG. 9A, a laser having, for example, 16 light emitting portions as shown in FIG. 11A. If the array light source 51 is divided into four in the array direction and used, the diffracted light from each region is deflected so as to illuminate the entire surface of the irradiated portion 16 and is enlarged (or reduced in some cases). .
Further, compared to the fly-eye lens system as shown in FIG. 9, at least the fly-eye lens interval (the interval from the first fly-eye lens 63 to the second fly-eye lens 64).
Can be shortened. Therefore, the optical system can be downsized.

(Embodiment 7) Next, an embodiment of the invention according to claim 7 will be described. FIG. 12 is a schematic configuration diagram of an exposure apparatus showing an embodiment of the invention according to claim 7, in which reference numeral 100 is a laser array light source (or semiconductor laser array light source), and 101 is the first to sixth embodiments (claims). A laser illumination optical system using the configuration according to any one of claims 1 to 6), 102 is a reticle that is an irradiated portion, 103
Is a projection lens, and 104 is a substrate stage.

In the exposure apparatus of this embodiment, the laser array light from the laser array light source 100 has the structure described in any one of Embodiments 1 to 6 (claims 1 to 6). The laser illuminating optical system 101 provides uniform irradiance on the reticle 102 which is the irradiated portion. Reticle 10
Reference numeral 2 denotes an exposure mask used to expose a circuit pattern on a wafer in a semiconductor device manufacturing process. The pattern of the reticle 102 is exposed by the projection lens 103 onto the wafer placed on the substrate stage 104. It Also, the exposure position is adjusted by the substrate stage 104 to expose a desired position on the wafer.

When the laser illumination optical system having the structure described in any one of the first to fourth embodiments (claims 1 to 4) is used as the laser illumination optical system 101, on the reticle surface. It is possible to perform uniform illumination in the above-mentioned examples, and the fifth and sixth embodiments are also possible.
When the laser illumination optical system described in (claims 5 and 6) is used, since the light beam in the direction orthogonal to the array of the laser array light source 100 is made uniform by the hologram element of the modulation pitch, interference fringes are generated on the reticle surface. The exposure can be performed with no uniform illumination. Therefore, it is possible to realize an exposure apparatus having good illumination performance and high performance.

(Embodiment 8) Next, an embodiment of the invention according to claim 8 will be described. FIG. 13 is a schematic configuration diagram of a laser processing apparatus showing an embodiment of the invention according to claim 8. In the figure, reference numeral 100 is a laser array light source (or semiconductor laser array light source), and 101 is the first to sixth embodiments. A laser illumination optical system using the configuration according to any one of claims 1 to 6, 105 is a lens, and 106 is a work.

In the laser processing apparatus of this embodiment, the laser light from the laser array light source 100 is emitted by the laser illuminating optical system according to any one of Embodiments 1 to 6 (claims 1 to 6). It is converted into a uniform beam, and the work 106 is shrunk or expanded by the lens 105 and irradiated. The workpiece 106 can be surface-processed or cut at the focused spot. Further, when the lens 105 is replaced with a projection lens, or in an arrangement in which the irradiated portion is directly used as the work, the work 106
Since it can be uniformly illuminated over a wide range, it can be used as laser annealing.

When the laser illuminating optical system having the structure described in any one of the first to fourth embodiments (claims 1 to 4) is used as the laser illuminating optical system 101, the Uniform illumination is possible, and the fifth and sixth embodiments (claims 5 and 6).
When the laser illumination optical system described in 6) is used, the light flux in the array orthogonal direction of the laser array light source 100 is made uniform by the hologram element having the modulation pitch, so that no interference fringes are generated on the work. Therefore, good laser processing and laser annealing can be performed.

(Embodiment 9) Next, an embodiment of the invention according to claim 9 will be described. FIG. 14 is a schematic configuration diagram of a projection device showing an embodiment of the invention according to claim 9. The projection device of the present embodiment includes laser array light sources 100r, 100g,
100b, laser illumination optical systems 110r, 110g and 110b using the configuration according to any one of Examples 1 to 6 (Claims 1 to 6), and color combining unit 113.
And a spatial modulator (light valve) 114 and a projection lens 115. Further, reference numeral 116 is a field lens, which is used for efficiently entering the image light from the light valve 114 into the projection lens pupil, but is not necessarily required. A dichroic prism or a dichroic mirror can be used as the color synthesizing means 113.

In this embodiment, the laser illumination optical system 110 is used.
r, 110g, and 110b are hologram elements 11 for example.
1r, 111g, 111b and fly-eye integrators 112r, 112g, 112b. That is, in this embodiment, the hologram elements 111r, 111 having the modulation pitch as described in Embodiment 5 (or Embodiment 6) are used.
g, 111b, laser array light sources 100r, 100g,
The intensity distribution in the array orthogonal direction of 100b is converted, and the array direction is a fly-eye integrator (fly-eye lens and condenser lens, or a hologram element having a function of a fly-eye integrator) 112r, 112g, 1
The illuminance is made uniform at 12b. This laser illumination optical system 11
If 0r, 110g, and 110b are used, interference fringes do not occur on the surface of the light valve 114 that is the irradiated portion. Also, the light source 1
00r, 100g, 100b and hologram element 111
A collimating lens array may be used between r, 111g and 111b. In addition, the hologram elements 111r and 11
Laser array light source 10 can be used with fly-eye integrators 112r, 112g, 112b without using 1g, 111b.
The array direction of 0r, 100g, 100b and the array orthogonal direction may be made uniform.

Laser illumination optical systems 110r, 110g, 1
The light flux from 10b is incident on the color synthesizing means 113, and the color synthesizing means 113 synthesizes three color laser lights of red (R), green (G) and blue (B). The light valve 114 is illuminated with the combined light of the three colors, and the image spatially modulated by the ride valve 114 is screened by the projection lens 115 (not shown).
Projected on. As the light valve 114, for example, a liquid crystal element can be used. Further, although a transmission type light valve is illustrated in FIG. 14, a reflection type light valve may be used to divide the illumination light and the projection light by a polarization beam splitter.

Further, in this embodiment, the light valve 1 is a single plate.
Although 14 is used, three light valves may be used. Although not shown, in the case of the three-plate type, one laser array light source and a light valve are arranged in the irradiated portion of the laser illumination optical system, and the image light from the three light valves is subjected to color combining means (for example, a dichroic prism). Combine and project on a screen with a projection lens.

In the projection apparatus of this embodiment, since the light source is a laser array light source, high output can be achieved by increasing the number of arrays even if the individual laser power is low. Also,
As in the present embodiment, the hologram element 111r of the modulation pitch is used for the light flux of the laser array light source in the laser array orthogonal direction.
When the intensity distribution is converted by 111g and 111b, uniform illumination can be performed without causing interference fringes on the light valve 114, so that a bright projection device with high display quality can be realized.

(Embodiment 10) Next, an embodiment of the invention according to claim 10 will be described. FIG. 15 is a schematic configuration diagram of a projection device showing an embodiment of the invention according to claim 10. The projection apparatus according to the present embodiment includes laser array light sources 100r and 10r.
0g, 100b and a laser illumination optical system (hologram element 111r, 111g, 11) using the configuration according to any one of Examples 1 to 6 (claims 1 to 6).
1b, fly-eye integrator 112), color combining means 113, light valve 114, and projection lens 115.
It is composed of. Further, reference numeral 116 is a field lens, which is used for efficiently entering the image light from the light valve 114 into the projection lens pupil, but is not necessarily required. A dichroic prism or a dichroic mirror can be used as the color synthesizing means 113.

In this embodiment, the laser illumination optical system includes three hologram elements 111r, 111g, 111b and one fly-eye integrator (for example, a fly-eye lens system or a hologram element having a fly-eye lens system function) 112. In the fly eye integrator 112, the color synthesizing means 113 causes red (R), green (G),
It is arranged in the optical path after combining the laser lights of the three colors of blue (B). With the configuration of this embodiment, the number of the fly-eye integrator 112 is sufficient as one set, so that the number of parts of the device can be reduced and the device can be downsized.

In the projection apparatus of this embodiment, since the light source is the laser array light source, high output can be obtained by increasing the number of arrays even if the individual laser power is small. Also,
As in the present embodiment, the hologram element 111r of the modulation pitch is used for the light flux of the laser array light source in the laser array orthogonal direction.
When the intensity distribution is converted by 111g and 111b, uniform illumination can be performed without causing interference fringes on the light valve, so that a bright projection device with high display quality can be realized. Furthermore, in the present embodiment, the fly-eye integrator 112 is shared, so that the number of parts is reduced, and it is possible to realize a compact projection device at low cost.

[0055]

As described above, in the laser illumination optical system according to claim 1, at least a laser array light source,
A laser illumination optical system comprising a fly-eye integrator in which the number of divisions of the fly-eye lens in the laser array direction is a divisor of the number of laser arrays, wherein the profile of array light incident on each array of the fly-eye lens is Since the spatial phases are different from each other, the number of divisions of the fly-eye lens is approximately the number of arrays of the laser array light by setting the periodic structure of the laser array and the size of the fly-eye lens to predetermined conditions. Even under several conditions, it is possible to make the illuminance uniform in the irradiated area.

According to a second aspect of the present invention, there is provided a laser illumination optical system which comprises a laser array light source and a fly-eye lens integrator which are periodically arranged, the laser array light source being periodically arranged. The number of divisions of the fly-eye lens is the divisor of the number of laser array light because the number of divisions of the fly-eye lens in the laser array direction is a divisor of the number of laser arrays to be lit. However, it is possible to make the illuminance uniform in the irradiated portion.

According to a third aspect of the present invention, in addition to the configuration of the first or second aspect, the laser illumination optical system is arranged between the laser array light source and the fly-eye lens and is incident on each array of the fly-eye lens. Since the laser array light has means for displacing the laser array light by a predetermined distance, by displacing the laser array light incident on the fly-eye lens by the displacing means, the number of divisions of the fly-eye lens is Even under the condition that the number of arrays is a divisor, it is possible to make the illuminance uniform in the irradiated portion.

In the laser illuminating optical system according to the present invention, the number of divisions of the laser array light source, the collimating lens array, and the fly-eye lens in the laser array direction is a divisor of the number of lit laser arrays. And a means for displacing the laser array light incident on each array of the fly-eye lens by a predetermined distance, which is arranged between the collimator lens array and the fly-eye lens. Even when the laser array is used and the number of divisions of the fly-eye lens is a divisor of the array number of the laser array light, the illuminance is uniformized in the irradiated area by displacing the laser array light incident on Can be achieved.

According to a fifth aspect of the present invention, in the laser illuminating optical system according to the first, third or fourth aspect, the fly-eye integrator is composed of a cylindrical lens array and a cylinder lens, and a light beam in a direction orthogonal to the laser array is a light source. It is characterized by being made uniform by the hologram element of the modulation pitch arranged between the fly eye integrator and the fly eye integrator.By displacing the laser array light incident on the fly eye lens, the division number of the fly eye lens is Even under the condition that the number of arrays of laser array light is a subdivision, the illuminance of the light flux component in the laser array direction can be made uniform, and the illuminance distribution is converted by the hologram element having a modulation pitch in the direction perpendicular to the laser array to achieve uniformization. Interference fringes do not appear in the irradiated part, and good illumination is possible.

According to a sixth aspect of the present invention, in the laser illumination optical system according to the first, third or fourth aspect, the fly-eye integrator is composed of a hologram element having the same function instead of the fly-eye lens, and is orthogonal to the laser array. Since the luminous flux in the direction is made uniform by the hologram element having the modulation pitch arranged between the light source and the fly-eye integrator, the same effect as in claim 5 can be obtained, and the illuminance in the laser array direction can be obtained. Since both the homogenization and the element for measuring the homogenization of the illuminance in the direction orthogonal to the array are composed of hologram elements, the illumination optical system can be made small.

In the exposure apparatus according to the seventh aspect, the first to the first aspects are provided.
The laser illumination optical system according to any one of 6 and a projection lens are provided, so that good illumination is possible even when the number of fly-eye integrator arrays is a divisor of the number of laser arrays. The device can be realized.

A laser processing apparatus according to claim 8 is the laser illumination optical system according to any one of claims 1 to 6,
Since a lens is provided, it is possible to realize a laser processing apparatus capable of good illumination even when the number of arrays of the fly-eye integrator is about the number of laser arrays.

According to the projection device of the ninth aspect, the first to third aspects are provided.
6. The laser illumination optical system according to any one of 6 above, a color synthesizing means, a spatial modulator (light valve), and a projection lens are provided, so that the number of arrays of the fly-eye integrator is a laser array. It is possible to realize a projection device with high color purity, which enables good illumination even under a condition of a few factors.

According to the projection apparatus of the tenth aspect, the projection apparatus of the ninth aspect is used.
In addition to the above configuration, a fly-eye integrator is arranged between the color synthesizing means and the spatial modulator.
Good lighting is possible even when the number of fly-eye integrator arrays is about the same as the number of laser arrays, and a projection device with high color purity can be realized.Furthermore, a single fly-eye integrator is used for multiple light sources. Therefore, the number of parts can be reduced, and a low-cost and small-sized projection device can be realized.

[Brief description of drawings]

FIG. 1 is a schematic plan configuration diagram of a laser illumination optical system showing an embodiment of the invention according to claim 1;

FIG. 2 is a schematic plan configuration diagram of a laser illumination optical system showing an embodiment of the invention according to claim 2;

FIG. 3 is a first part of the laser illumination optical system shown in FIGS. 1 and 2;
It is a figure which shows the profile of the laser array light injecting into a fly's eye lens.

FIG. 4 is a schematic plan configuration diagram of a laser illumination optical system showing a first embodiment of the invention according to claim 3;

5 is a diagram showing a profile of laser array light incident on one array (lens portion) of the first fly-eye lens of the laser illumination optical system shown in FIG.

6 is an intensity distribution of laser array light (arrays 1 to 4) that has passed through each of the four-divided arrays (lens parts) of the fly-eye lens of the laser illumination optical system shown in FIG. 1, FIG. 2, or FIG. It is a figure which shows the intensity distribution added on the irradiated part 16.

FIG. 7 is a schematic plan configuration diagram of a laser illumination optical system showing a second embodiment of the invention according to claim 3;

FIG. 8 is a schematic plan configuration diagram of a laser illumination optical system showing an embodiment of the invention according to claim 4;

FIG. 9 is a diagram showing an embodiment of the invention according to claim 5, (a) is a schematic plan configuration diagram of a laser illumination optical system,
(B) is a schematic side view of a laser illumination optical system.

10 is a diagram showing the relationship between the position of the hologram surface of the hologram element used in the laser illumination optical system shown in FIG. 9 and the grating pitch.

FIG. 11 is a diagram showing an embodiment of the invention according to claim 6, (a) is a schematic plan configuration diagram of a laser illumination optical system,
(B) is a schematic side view of a laser illumination optical system.

FIG. 12 is a schematic configuration diagram of an exposure apparatus showing an embodiment of the invention according to claim 7;

FIG. 13 is a schematic configuration diagram of a laser processing apparatus showing an embodiment of the invention according to claim 8;

FIG. 14 is a schematic configuration diagram of a projection device showing an embodiment of the invention according to claim 9;

FIG. 15 is a schematic configuration diagram of a projection device showing an embodiment of the invention according to claim 10;

[Explanation of symbols]

10, 11: Laser array light source 12: Displacement means 12a, 12c, 12d: Parallel plate 13 constituting the displacement means 13: First fly-eye lens 14: Second fly-eye lens 15: Condenser lens 16: Irradiated parts 41a, 41c , 41d: Hologram element 51 constituting displacement means: Laser array light source 52: Collimating lens array 61: Hologram element with modulation pitch 62: Hologram element having fly-eye integrator function 63: First fly-eye lens (cylindrical lens array) 64 : Second fly-eye lens (cylindrical lens array) 65: Condenser lens (cylindrical lens) 100: Laser array light source (or semiconductor laser array light source) 100r, 100g, 100b: Laser array light source (or semiconductor laser array light source) ) 101: laser illumination optical system 102: reticle (exposure mask) 103: projection lens 104: substrate stage 105: lens 106: works 110r, 110g, 110b: laser illumination optical system 111r, 111g, 111b: hologram element 112: fly Eye integrators 112r, 112g, 112b: Fly eye integrator 113: Color combining means 114: Spatial modulator (light valve) 115: Projection lens 116: Field lens

Front page continuation (51) Int.Cl. ⁷ identification code FI theme code (reference) G03F 7/20 501 G02B 27/00 V (72) Inventor Kenji Kameyama 1-3-6 Nakamagome, Ota-ku, Tokyo In stock company Ricoh (72) Inventor Ikuo Kato 1-3-6 Nakamagome, Ota-ku, Tokyo ・ In stock company Ricoh (72) Inventor Yasuyuki Takiguchi 1-3-6 Nakamagome, Ota-ku, Tokyo F-term in Ricoh (reference) 2H052 BA02 BA09 BA11 BA12 BA14 2H097 CA17 GB00 LA10 5F046 BA04 CA03 CA05 CB13 CB14 CB23

Claims (10)

[Claims] 1. A laser illumination optical system comprising at least a laser array light source and a fly-eye integrator in which the number of divisions of the fly-eye lens in the laser array direction is a divisor of the number of laser arrays. A laser illumination optical system characterized in that the spatial phase of the profile of array light incident on each array is different. 2. A laser illumination optical system comprising a laser array light source arranged periodically and a fly-eye lens integrator, wherein the laser array light source comprises a non-light emitting section arranged periodically. A laser illumination optical system, wherein the number of divisions of the eye lens in the laser array direction is a divisor of the number of laser arrays to be turned on. 3. The laser illumination optical system according to claim 1 or 2, wherein the laser array light that is arranged between the laser array light source and the fly-eye lens and is incident on each array of the fly-eye lens is at a predetermined distance. A laser illuminating optical system having means for displacing only the laser illuminating system. 4. A laser array light source, a collimating lens array, a fly-eye integrator in which the number of divisions of the fly-eye lens in the laser array direction is a divisor of the number of illuminated laser arrays, the collimating lens array and the fly. A laser illuminating optical system comprising means arranged between the eye lenses and displacing a laser array light incident on each array of the fly-eye lenses by a predetermined distance. 5. The laser illumination optical system according to claim 1, 3 or 4, wherein the fly-eye integrator is composed of a cylindrical lens array and a cylinder lens, and a light beam orthogonal to the laser array is a light source and a fly-eye integrator. A laser illuminating optical system characterized by being made uniform by a hologram element having a modulation pitch arranged between. 6. The laser illumination optical system according to claim 1, 3 or 4, wherein the fly-eye integrator is composed of a hologram element having the same function in place of the fly-eye lens, and a light flux in a direction orthogonal to the laser array is A laser illumination optical system characterized by being made uniform by a hologram element having a modulation pitch arranged between a light source and a fly-eye integrator. 7. An exposure apparatus comprising the laser illumination optical system according to claim 1 and a projection lens. 8. A laser processing apparatus comprising the laser illumination optical system according to claim 1 and a lens. 9. A projection device comprising the laser illumination optical system according to claim 1, a color synthesizing means, a spatial modulator, and a projection lens. 10. The projection device according to claim 9, wherein a fly-eye integrator is arranged between the color synthesizing means and the spatial modulator.