JP2007027612A - Irradiation apparatus and irradiation method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an irradiation apparatus capable of realizing high efficiency of irradiation processing, while preventing uneveness in irradiation, using a simple configuration. <P>SOLUTION: Two semiconductor lasers 11A, 11B emit emission laser beams having different wavelengths, respectively. A dichroic prism 31 couples the emission laser beams on the same axis (on Z-axis). A cylindrical lens array pair 41 generates a secondary light source on a cylindrical lens array 41B, on the basis of the coupled emission laser beam. A divergence angle adjusting lens 22B executes correction so that chromatic aberrations are not be generated between luminous fluxes, based on the emission laser beams from the semiconductor lasers 11A, 11B in the luminous flux from the secondary light source. Then, an irradiation target 6 is irradiated with the luminous flux from the corrected secondary light source. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an irradiation apparatus and an irradiation method for irradiating an object with light using a semiconductor laser as a light source.

  Conventionally, a method of annealing a silicon thin film using a continuously oscillating laser in order to form a circuit element or the like with p-Si (polycrystalline silicon) in a manufacturing process of a liquid crystal display device or an organic EL (ElectroLuminescence) display device, for example. It has been known. Specifically, for example, a heating layer is provided on an a-Si (amorphous-silicon) layer to absorb laser light, and this a-Si layer is annealed by heat generated at that time. The method of annealing with laser light in this way is advantageous in that a silicon thin film is partially irradiated, so that the entire substrate can be prevented from becoming high temperature, and a glass substrate can be used as the substrate. .

  Here, for the purpose of improving the throughput of such annealing treatment, some attempts have been made to combine a plurality of laser beams for annealing. As such an attempt, first, a method of concentrically combining the S-polarized component and the P-polarized component of the laser light can be considered. However, in this case, only the combination of two laser beams can be realized using the S-polarized component and the P-polarized component. Therefore, the throughput cannot be sufficiently improved and the versatility is poor.

  Thus, for example, Patent Document 1 discloses an annealing method in which two laser light sources that emit laser beams having different wavelengths are used, and laser beams emitted from the laser beams are coupled coaxially by a dichroic mirror. Specifically, as shown in FIG. 7, the light beam emitted from the laser light source 101 is combined with the light beam emitted from the laser light source 102 having a wavelength different from that by the dichroic mirror 103, and the irradiated object 104. Is incident on.

  Patent Document 2 discloses an annealing method in which a plurality of laser light sources are coupled with a condenser lens and uniform irradiation is performed by intensity distribution forming means. Specifically, as shown in FIG. 8, the light beams emitted from the plurality of laser light sources 201 to 203 are combined by the condenser lens 205 via the mirrors 204 </ b> A to 204 </ b> D, and the intensity distribution shaping means 206 further increases the intensity. It is made uniform and shaped into a linear beam by the beam shape shaping means 207 so as to enter the irradiated object 208.

JP-A-55-148431 JP 2002-139697 A

  Here, since the annealing method disclosed in Patent Document 1 uses laser beams having different wavelengths, it is possible to combine three or more laser beams. However, when only the a-Si layer is annealed as described above, for a-Si and p-Si, the highly efficient absorption wavelength region is a shorter wavelength region than 400 nm. Kinds are limited. Specifically, for example, a laser that outputs a third harmonic or a fourth harmonic of YAG can be cited, but since these outputs are as low as about 10 W, they are used in a general laser annealing apparatus. Compared to the output of the excimer laser (about 300 W), the throughput cannot be improved sufficiently. In addition, since Patent Document 1 does not mention means for uniform irradiation, uniform irradiation cannot be performed, and uneven irradiation occurs.

  On the other hand, in the annealing method disclosed in Patent Document 2, intensity distribution forming means is provided as means for uniform irradiation as described above. Further, since a plurality of laser light sources are used, the throughput can be sufficiently improved. However, since a pulse coherent laser with high coherence is used as the laser light source, interference fringes are generated in the irradiated light due to the splitting and combining of the wavefronts of the light flux by the intensity distribution forming means. Therefore, it is actually difficult to perform uniform irradiation, and uneven irradiation will occur. In addition, since the pulsed solid-state laser is expensive, the cost of parts increases.

  Thus, with the conventional technology, it has been difficult to achieve high efficiency of the irradiation process while preventing uneven irradiation with an inexpensive configuration.

  The present invention has been made in view of such problems, and an object thereof is to provide an irradiation apparatus and an irradiation method capable of realizing high efficiency of irradiation processing while preventing uneven irradiation with an inexpensive configuration. There is.

  The irradiation apparatus of the present invention includes a plurality of semiconductor laser light sources that emit laser beams having different wavelengths, a coupling optical system that coaxially couples the emitted laser beams respectively emitted from the plurality of semiconductor laser light sources, and this coupling A homogenizing optical system for generating a secondary light source based on the emitted laser light combined by the optical system and a light chromatic aberration between the light fluxes based on the emitted laser light in the light flux from the secondary light source. The apparatus includes a chromatic aberration correcting unit that corrects these chromatic aberrations, and an irradiation optical system that irradiates the irradiated object with a light beam from the secondary light source corrected by the chromatic aberration correcting unit.

  In the irradiation method of the present invention, a plurality of emitted laser beams having different wavelengths emitted from a plurality of semiconductor laser light sources are coupled on the same axis, and a secondary light source is generated based on the combined emitted laser beams. In the luminous flux from the secondary light source, these chromatic aberrations are corrected so that no photochromatic aberration occurs between the luminous fluxes based on the plurality of emitted laser beams, and the corrected luminous flux from the secondary light source is irradiated. An object is irradiated.

  In the irradiation apparatus and the irradiation method of the present invention, a plurality of emitted laser beams having different wavelengths are emitted from a plurality of semiconductor laser light sources and are coaxially coupled. A secondary light source is generated based on the combined emitted laser light. Then, correction is made so that chromatic aberration does not occur in the light beam from the secondary light source, and the light beam from the corrected secondary light source is irradiated onto the irradiated object.

  According to the irradiation apparatus or the irradiation method of the present invention, a plurality of emission laser beams having different wavelengths emitted from a plurality of semiconductor laser light sources are coupled on the same axis, and based on the combined emission laser beams. The correction is made so that chromatic aberration does not occur in the generated light beam from the secondary light source, and the object to be irradiated is irradiated with the light beam from the corrected secondary light source. It is possible to achieve high efficiency of irradiation processing while using a stable light source and preventing uneven irradiation with an inexpensive configuration.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[First Embodiment]
1A and 1B show an overall configuration of an irradiation apparatus according to the first embodiment of the present invention. FIG. 1A is a side view seen from the X-axis direction, and FIG. 1B is a Y-axis direction. FIG. 1C is a side view of a part of the irradiation apparatus as viewed from the Z-axis direction.

  This irradiation apparatus includes two semiconductor lasers 11A and 11B, two collimator lenses 21A and 21B corresponding to the semiconductor lasers 11A and 11B, a divergence angle adjusting lens 22B corresponding only to the semiconductor laser 11B, and a dichroic prism 31, respectively. Laser beam emitted from the semiconductor lasers 11A and 11B to the irradiated object 6 mounted on the stage 7, which includes the cylindrical lens array pair 41, the condenser lens 51, and the condenser lens 52. Are combined and irradiated.

  The semiconductor lasers 11A and 11B emit laser beams having different wavelengths in the Z-axis direction or the X-axis direction, respectively, and are composed of broad area type semiconductor lasers each having the X-axis direction or the Z-axis direction as a longitudinal direction. Has been. As these semiconductor lasers 11A and 11B, those having an emitted laser beam having a wavelength of about 790 to 980 nm are preferably used. The wavelength difference between the laser beams emitted from the semiconductor lasers 11A and 11B is preferably about 30 to 40 nm. This is because if the wavelength difference is too large, it becomes difficult to couple the emitted laser light in the dichroic prism 31.

  The collimator lens 21A is a lens having a positive power, and makes the Y-axis direction component of the laser beam emitted from the semiconductor laser 11A a parallel light beam (FIG. 1A). The collimator lens 21B is also a lens having a positive power, and the Y-axis direction component of the laser beam emitted from the semiconductor laser 11B is a parallel light beam (FIG. 1C). The arrangement of the collimator lenses 21A and 21B constitutes a one-side telecentric system with the arrangement of the semiconductor lasers 11A and 11B, respectively.

  The dichroic prism 31 has a joint surface 31A that transmits only light in a specific wavelength region, and transmits the emitted laser light from the semiconductor laser 11A, while reflecting the emitted laser light from the semiconductor laser 11B. is there. With such a configuration, in the dichroic prism 31, the laser beams emitted from the semiconductor lasers 11A and 11B are coupled on the same axis (in this case, on the Z axis) (FIG. 1B). The dichroic prism 31 corresponds to a specific example of “coupled optical system” in the invention.

  The cylindrical lens array pair 41 includes a pair of cylindrical lens arrays 41A and 41B, and these cylindrical lens arrays 41A and 41B are arranged in an array along the X-axis direction (FIG. 1B). Further, the cylindrical lens arrays 41A and 41B have the same focal length, and are opposed to each other at an interval equivalent to the focal length. With this configuration, in the cylindrical lens array pair 41, the X-axis direction component of the emitted laser light combined by the dichroic prism 31 is divided into a plurality of light beams by the cylindrical lens array 41A, and a secondary light source is provided on the cylindrical lens array 41B. It is generated (FIG. 1B). The cylindrical lens array pair 41 corresponds to a specific example of “homogenizing optical system” in the present invention.

  As described above, the divergence angle adjusting lens 22B converts the light beam from the secondary light source generated on the cylindrical lens array 41B into the light beam based on the laser beam emitted from the semiconductor laser beam 11A and the laser beam emitted from the semiconductor laser beam 11B. These chromatic aberrations are corrected so that chromatic aberration does not occur with the light flux based on them. Specifically, by adjusting the divergence angle in the Z-axis direction in the laser beam emitted from the semiconductor laser beam 11B, correction is made so that chromatic aberration does not occur in the light beam from the secondary light source. More specifically, for example, when the wavelength of the laser beam emitted from the semiconductor laser 11B is larger than that of the laser beam emitted from the semiconductor laser beam 11A, the divergence angle of the laser beam emitted from the semiconductor laser beam 11B is increased. On the other hand, when the wavelength of the laser beam emitted from the semiconductor laser 11B is smaller than that of the laser beam emitted from the semiconductor laser beam 11A, the laser beam emitted from the semiconductor laser beam 11B is adjusted. Adjustment is made so that the divergence angle of the emitted laser light is reduced (so that the light is focused). With such a configuration, the chromatic aberration between the emitted laser beams respectively emitted from the two semiconductor lasers 11A and 11B in the secondary light source is eliminated, and the focal points in the secondary light source are matched. The divergence angle adjusting lens 22B is arranged so as to be deviated from the one-side telecentric system with the semiconductor laser 11B. The divergence angle adjusting lens 22B corresponds to a specific example of “chromatic aberration correcting means” in the present invention.

  The condenser lens 51 superimposes the X-axis direction components of the light beam from the secondary light source generated on the cylindrical lens array 41B, and uniformly irradiates the irradiated surface of the irradiated object 6 (FIG. 1B). is there. The condensing lens 52 condenses the Y-axis direction component of the light beam from the secondary light source and irradiates the irradiated surface of the irradiated object 6 (FIG. 1A). In this way, the irradiation target 6 is irradiated with a linear beam that is made the X-axis direction the long-axis direction and is made uniform in the X-axis direction. Here, in the condenser lens 51 and the condenser lens 52, the chromatic aberration in the semiconductor lasers 11A and 11B is corrected. The condenser lens 51 and the condenser lens 52 correspond to a specific example of “irradiation optical system” in the present invention.

  The irradiated object 6 is irradiated with irradiated light (as described above, the X-axis direction is the long-axis direction and the linear beam is made uniform in the X-axis direction). Specifically, for example, a TFT (Thin Film Transistor) panel in a liquid crystal display device or an organic EL display device can be used. Hereinafter, the irradiated object 6 according to the present embodiment will be described as an example in which an a-Si layer 62 and a heating layer 63 are stacked on a substrate 61.

  The substrate 61 is made of, for example, a glass substrate. Further, the a-Si layer 62 is a layer that is actually a target of the annealing process. The a-Si layer is converted to p-Si by annealing, and forms a part of a circuit element such as a TFT. The heating layer 63 is made of, for example, molybdenum (Mo), and is a layer for conducting generated heat to the a-Si layer 62 by absorbing the irradiated linear beam. In this way, the annealing process using the irradiation light is performed on the a-Si layer 62 of the irradiation object 6.

  The stage 7 mounts the irradiated object 6 and scans the irradiated object 6 in the Y-axis direction on the mounting surface in accordance with control by a scanning control unit (not shown), so that the irradiation position of the irradiated light is relatively set. It is possible to move and irradiate the entire irradiated surface of the irradiated object 6.

  Next, with reference to FIGS. 1A to 1C, the operation of the irradiation apparatus having such a configuration will be described.

  First, the laser light emitted from the semiconductor laser 11A having the broad area direction as the X-axis direction becomes a parallel light beam in the Y-axis direction component by the collimator lens 21A, enters the dichroic prism 31, and passes through the joint surface 31A ( FIG. 1 (A), (B)). On the other hand, the laser light emitted from the semiconductor laser 11B having the broad area direction as the Z-axis direction becomes a parallel beam in the Y-axis direction by the collimator lens 21B, and the divergence angle in the Z-axis direction is adjusted by the divergence angle adjustment lens 22B. Then, the light enters the dichroic prism 31 and is reflected by the joint surface 31A (FIGS. 1B and 1C). The laser beams emitted from the semiconductor lasers 11A and 11B are combined in the dichroic prism 31 to become a combined light beam on the same axis (Z-axis direction) (FIG. 1B).

  Next, the combined light beam emitted from the dichroic prism 31 in this way is divided into a plurality of light beams by the cylindrical lens array 41A (FIG. 1B). Then, a secondary light source is generated on the cylindrical lens array 41B from the plurality of divided light beams (FIG. 1B).

  Here, as described above, the divergence angle in the Z-axis direction of the laser beam emitted from the semiconductor laser 11B is adjusted by the divergence angle adjustment lens 22B (FIG. 1B), and therefore, on the cylindrical lens array 41B. In the generated light beam from the secondary light source, chromatic aberration does not occur between the light beam based on the laser beam emitted from the semiconductor laser 11A and the light beam based on the laser beam emitted from the semiconductor laser 11B, and the positions of the secondary light sources coincide with each other. (FIG. 1B). Accordingly, not only the laser beam emitted from the semiconductor laser 11A but also the laser beam emitted from the semiconductor laser 11B can be applied to the irradiation of the irradiated object 6, and the irradiation intensity of the irradiated light to the irradiated object 6 is improved. To do.

  Next, the light beams from the secondary light source coupled on the Z axis in such a manner that their positions coincide with each other are superimposed on the position of the irradiated surface of the irradiated object 6 by the condenser lens 51, and the X axis The luminance in the direction is made uniform (FIG. 1B). On the other hand, the Y-axis direction component is condensed by the condenser lens 52 (FIG. 1A). In this way, the X-axis direction is taken as the long-axis direction, and a linear beam uniformized in the X-axis direction is irradiated onto the heating layer 63 of the irradiation object 6 (FIGS. 1A and 1B). The heat generated in the heating layer 63 is conducted to the a-Si layer 62, whereby the a-Si layer 62 is annealed. In this state, the stage 7 on which the irradiation object 6 is mounted scans in the Y-axis direction under the control of a scanning control unit (not shown), so that the entire irradiation surface of the irradiation object 6 is irradiated.

  Here, FIG. 2 shows the relationship between the wavelength λ of the emitted laser beam and the light absorption rate in the heating layer when the heating layer 63 is made of Mo. As indicated by reference numerals P1 and P2 in this figure, for example, when the wavelengths of the laser beams emitted from the semiconductor lasers 11A and 11B are λ = 790 nm and 830 nm, respectively, the light absorption rate in the heating layer 63 is about The same value is obtained at 55%, and the amount of heat conducted to the a-Si layer 62 is also equivalent. That is, in the present embodiment, since both the laser beam emitted from the semiconductor laser 11A and the laser beam emitted from the semiconductor laser 11B can be applied to the irradiation of the object 6 as described above, When the wavelength λ is set in this way, the irradiation intensity to the irradiated object 6 is approximately doubled as compared with the conventional case, and the efficiency (throughput) of the annealing process is also improved approximately twice.

  FIG. 3 shows the relationship between the thickness of the heating layer 63 and the light transmittance when the wavelength of the emitted laser light is λ = 800 nm. As indicated by reference numeral P3 in this figure, for example, if the thickness of the heating layer 63 is 100 nm or more, the light transmittance is almost 0%, and all of the emitted laser light is absorbed by the heating layer 63. Therefore, since the irradiation laser beam does not reach the lower layer of the heating layer 63, for example, even when this lower layer is a multilayer film, the variation in annealing treatment due to the film thickness error between individual irradiated objects is prevented. In addition, variations in the operation of the finally formed circuit elements can be suppressed.

  As described above, in the present embodiment, the emitted laser beams having different wavelengths emitted from the two semiconductor lasers 11A and 11B are coupled on the same axis (on the Z axis) by the dichroic prism 31 and are combined. The divergence angle adjusting lens 22B so that chromatic aberration does not occur between the light beams from the secondary light sources generated on the cylindrical lens array 41B based on the emitted laser light and the light beams based on the emitted laser light from the semiconductor lasers 11A and 11B. Is corrected, and the light beam from the corrected secondary light source is irradiated onto the irradiated object 6, so that it is possible to achieve high efficiency of the irradiation process while preventing uneven irradiation. .

  In addition, since the laser light source is composed of a semiconductor laser that is less expensive than a conventional solid-state pulse laser, it is possible to configure the irradiation device with a structure that is less expensive than the conventional one.

  Further, since the semiconductor lasers 11A and 11B are constituted by broad area type semiconductor lasers, a high-power semiconductor laser can be used as a light source, and as a result, annealing can be performed at a higher speed. Therefore, it is possible to configure an irradiation apparatus suitable for laser annealing.

  Hereinafter, an irradiation apparatus according to another embodiment of the present invention will be described. In addition, the same code | symbol is attached | subjected to the same thing as the component in 1st Embodiment, and description is abbreviate | omitted suitably.

[Second Embodiment]
FIG. 4 shows the overall configuration of the irradiation apparatus according to the second embodiment of the present invention, and is a top view as seen from the Y-axis direction.

  In the irradiation apparatus according to the present embodiment, the emitted laser beams having different wavelengths emitted from the four semiconductor lasers 11A to 11D are coupled coaxially (on the Z axis) by the three dichroic prisms 31 to 33. Is. Specifically, in the irradiation apparatus according to the first embodiment, two semiconductor lasers 11C and 11D, collimator lenses 21C and 21D, and a divergence angle adjusting lens 22C arranged corresponding to the semiconductor lasers 11C and 11D, respectively. , 22D, the dichroic prism 32 that couples the laser beams emitted from the semiconductor lasers 11C, 11D on the X axis, and the combined laser beams emitted from these semiconductor lasers 11C, 11D and the semiconductor lasers 11A, 11B by the dichroic prism 31 And a dichroic prism 33 for coupling the combined luminous flux of the laser beam emitted from the laser beam coaxially (on the Z axis).

  Here, the wavelengths of the laser beams emitted from the semiconductor lasers 11A and 11B are, for example, λ = 790 nm and 830 nm, respectively, while the wavelengths of the laser beams emitted from the semiconductor lasers 11C and 11D are, for example, λ. = 940 nm and 980 nm. That is, first, the emitted laser beams having closer wavelengths are combined. This is because the dichroic prism 33 can be easily manufactured with this configuration.

  With such a configuration, the laser beams emitted from the semiconductor lasers 11A and 11B become parallel light beams in the Y-axis direction by the collimator lenses 21A and 21B, respectively, and are coaxially formed by the dichroic prism 31 as in the first embodiment. Combined on top (on Z axis). On the other hand, laser beams emitted from the semiconductor lasers 11C and 11D having the broad area directions as the X-axis direction and the Z-axis direction, respectively, become parallel light beams in the Y-axis direction by the collimator lenses 21C and 21D, respectively, and are joined to the dichroic prism 31. They are coupled coaxially (on the X axis) by reflection or transmission at 32D. Then, the combined luminous flux of the laser beams emitted from the semiconductor lasers 11A and 11B and the combined luminous flux of the laser beams emitted from the semiconductor lasers 11C and 11D are coaxially (on the Z axis) by transmission or reflection at the dichroic prism 33. ).

  Here, based on the combined light beam emitted from the dichroic prism 33 in this way, a secondary light source is generated on the cylindrical lens array 41B as in the first embodiment, but the divergence angle adjusting lenses 22B to 22B 22D adjusts the divergence angle in the Z-axis direction or the X-axis direction in the emitted laser light from the semiconductor lasers 11B to 11D, and therefore, between the emitted laser lights from the semiconductor lasers 11A to 11D at the position of the secondary light source. Chromatic aberration does not occur, and the secondary light source positions coincide with each other. Therefore, all of the laser beams emitted from the semiconductor lasers 11 </ b> A to 11 </ b> D can be applied to the irradiation of the irradiated object 6.

  As described above, in the present embodiment, the emitted laser beams having different wavelengths emitted from the four semiconductor lasers 11A to 11D are coupled coaxially (on the Z axis) by the three dichroic prisms 31 to 33. Therefore, compared with the first embodiment, the irradiation intensity to the irradiated object 6 can be increased, and the efficiency (throughput) of the annealing process can be further improved. That is, for example, if the light absorptance of the laser beams emitted from the semiconductor lasers 11A to 11D in the heating layer 63 is the same value, the irradiation intensity to the irradiated object 6 is compared with that in the first embodiment. Furthermore, it becomes about twice, and the efficiency (throughput) of the annealing process is further improved about twice.

[Third Embodiment]
5A and 5B show an overall configuration of an irradiation apparatus according to the third embodiment of the present invention. FIG. 5A is a side view seen from the X-axis direction, and FIG. 5B is a Y-axis direction. The top view seen from each is represented.

  The irradiation apparatus according to the present embodiment includes a rod integrator 42 instead of the cylindrical lens array pair 41, a collimator lens 23B instead of the collimator lens 21B and the divergence angle adjustment lens 22B, and a pair of lenses 53, 54 are provided.

  The rod integrator 42 generates a region uniform in the X-axis direction on the exit surface 42A by repeatedly reflecting only the X-axis direction component of the combined light beam from the dichroic prism 31 on its inner wall surface ( FIG. 5 (B)). That is, the rod integrator 42 corresponds to a specific example of “homogenizing optical system” in the present invention. Further, unlike the case of the cylindrical lens array pair 41 in the first embodiment, this rod integrator 42 does not cause chromatic aberration in the emitted light beam without correction by the divergence angle adjusting lens 22B. ing. That is, the rod integrator 42 corresponds to a specific example of “chromatic aberration correcting means” in the present invention.

  The collimator lens 23B converts the Y-axis direction component of the emitted laser light from the emitted laser 11B into a parallel light beam, and corresponds to the collimator lens 21B in the first embodiment. That is, as described above, chromatic aberration does not occur in the light beam emitted from the rod integrator 42, so that the divergence angle adjusting lens 22B is not necessary.

  The lenses 53 and 54 project the uniformized region of the exit surface 42A of the rod integrator 42, so that along with the condenser lens 52, the X-axis direction is set as the major axis direction on the heating layer 63 of the irradiated object 6. A linear beam uniformized in the X-axis direction is irradiated.

  As described above, in the present embodiment, the rod integrator 42, which is a uniformizing optical system, also functions as a chromatic aberration correction unit, so that the divergence angle adjustment lens 22B is not necessary, and in the first embodiment. In addition to the effect, the configuration of the entire irradiation apparatus can be further simplified.

  Also in this embodiment, as in the case of the second embodiment, the irradiation apparatus may be configured using four semiconductor lasers.

[Fourth Embodiment]
FIG. 6 illustrates the overall configuration of the irradiation apparatus according to the fourth embodiment of the present invention, and is a top view as viewed from the Y-axis direction.

  In the irradiation apparatus of the present embodiment, instead of the broad area type semiconductor lasers 11A and 11B, multi-emitter type semiconductor lasers 12A and 12B in which a plurality of semiconductor laser elements are arrayed in the X-axis direction or the Z-axis direction, respectively. Is provided. This multi-emitter type semiconductor laser has a higher output than the broad area type semiconductor laser (generally, a high output of one digit or more). Compared with the form, the irradiation intensity to the irradiation object 6 becomes larger, and the efficiency (throughput) of the annealing process is further improved.

  As described above, in the present embodiment, the two laser light sources are configured by the multi-emitter semiconductor lasers 12A and 12B having higher output than the broad area semiconductor lasers 11A and 11B, respectively. Compared with the embodiment, the irradiation intensity to the irradiation object 6 can be increased, and the efficiency (throughput) of the annealing process can be further improved.

  Also in this embodiment, as in the case of the second embodiment, the irradiation apparatus may be configured using four semiconductor lasers. Further, as in the case of the third embodiment, the uniformizing optical system and the chromatic aberration correcting means may be configured by a rod integrator 42 instead of the cylindrical lens array pair 41 and the divergence angle adjusting lens 22B. .

  Although the present invention has been described with reference to the first to fourth embodiments, the present invention is not limited to these embodiments, and various modifications can be made.

  For example, in the above embodiment, the case where two or four semiconductor lasers are used as the laser light source has been described. However, the number of semiconductor lasers is not limited to this, and the laser light source may be configured by an arbitrary number of two or more. Is possible. If the number of semiconductor lasers increases, the irradiation intensity to the irradiated object 6 can be increased accordingly, and the efficiency (throughput) of the annealing process can be further improved.

  In the above embodiment, the configuration of the irradiation apparatus has been specifically described. However, the configuration of the irradiation apparatus is not limited to these cases. For example, in addition to each lens, other lenses are arranged. You may make it do. Specifically, for example, in the optical path between the semiconductor laser and the object to be irradiated 6, an isolator for preventing the reflected light from the irradiated surface of the object to be irradiated 6 from returning to the semiconductor laser may be further provided. . This isolator can be composed of, for example, a polarizing beam splitter and a ¼λ plate. When configured in this way, in addition to the effects in the above embodiment, the semiconductor laser can be prevented from being destroyed by the reflected light from the irradiated object.

It is a figure showing the whole irradiation apparatus composition concerning a 1st embodiment of the present invention. It is a characteristic view showing the relationship between the wavelength of an emitted laser beam, and the absorption factor in the heating layer of a to-be-irradiated object. It is a characteristic view showing the relationship between the film thickness in the heating layer of a to-be-irradiated object, and the transmittance | permeability. It is a figure showing the whole irradiation apparatus composition concerning a 2nd embodiment. It is a figure showing the whole structure of the irradiation apparatus which concerns on 3rd Embodiment. It is a figure showing the whole structure of the irradiation apparatus which concerns on 4th Embodiment. It is a figure showing an example of the composition of the conventional irradiation device. It is a figure showing the other example of a structure of the conventional irradiation apparatus.

Explanation of symbols

11A to 11D, 12A, 12B ... Semiconductor laser, 21A-21D ... Collimator lens, 22B-22D ... Divergence angle adjusting lens, 23B ... Collimator lens, 31-33 ... Dichroic prism, 31A, 32D, 33A ... Joint surface, 41 ... Cylindrical lens array pair, 41A, 41B ... cylindrical lens array, 42 ... rod integrator, 42A ... exit surface, 51 ... condenser lens, 52 ... condensing lens, 61 ... substrate, 62 ... a-Si layer, 63 ... heating layer, 6 ... object to be irradiated, 7 ... stage.

Claims (9)

A plurality of semiconductor laser light sources that emit laser beams of different wavelengths;
A coupling optical system for coaxially coupling the emitted laser beams respectively emitted from the plurality of semiconductor laser light sources;
A homogenizing optical system for generating a secondary light source based on the emitted laser light coupled by the coupling optical system;
Chromatic aberration correction means for correcting chromatic aberration so that chromatic aberration does not occur between the respective light beams based on the emitted laser light in the light beam from the secondary light source;
An irradiation optical system comprising: an irradiation optical system that irradiates an object with a light beam from a secondary light source corrected by the chromatic aberration correction unit. The irradiation apparatus according to claim 1, wherein the chromatic aberration correction unit corrects chromatic aberration by adjusting a divergence angle of the emitted laser light. The irradiation apparatus according to claim 1, wherein the homogenizing optical system includes one or more cylindrical lens arrays. The irradiation apparatus according to claim 1, wherein the homogenizing optical system and the chromatic aberration correcting optical system are configured by one or more rod integrators. The irradiation apparatus according to claim 1, wherein each of the plurality of semiconductor laser light sources includes a broad area type semiconductor laser. 2. The irradiation apparatus according to claim 1, wherein each of the plurality of semiconductor laser light sources includes a multi-emitter semiconductor laser in which a plurality of semiconductor laser elements are arrayed in a one-dimensional direction. The irradiation apparatus according to claim 1, further comprising an isolator that prevents a light beam reflected by the irradiation object from returning to the plurality of semiconductor laser light sources. The laser annealing apparatus configured to anneal the irradiated object by irradiating the irradiated object with a light beam from the corrected secondary light source, respectively. Irradiation equipment. A plurality of emission laser beams having different wavelengths emitted from a plurality of semiconductor laser light sources are coupled on the same axis,
Generating a secondary light source based on the combined emitted laser light;
In the luminous flux from the secondary light source, these chromatic aberrations are corrected so that chromatic aberration does not occur between the luminous fluxes based on the plurality of emitted laser beams,
An irradiation method characterized by irradiating an irradiated object with a light beam from a corrected secondary light source.

Images