JP2005219400A - Multi-beam microstructure optical modeling method and apparatus using different wavelength laser beam - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multibeam stereolithography for microstructures using different wavelength laser beams which has a three dimensional space selectivity on the nano level by using, in addition to a photocuring reaction-inducing laser beam, a reaction-promoting laser beam having a wavelength different from that of the photocuring reaction-inducing laser beam and a device for the multibeam stereolithography. <P>SOLUTION: While a resin is irradiated with a photocuring reaction-inducing laser beam 4 at an intensity low enough not to induce photocuring reaction, the same spot of the resin is irradiated additionally with a reaction-promoting laser beam 5 with a different wavelength so that a photocuring reaction 6 takes place only in the neighborhood of the focused spot. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a multi-beam microstructure optical modeling method and apparatus using different wavelength laser light.

  In recent years, optical shaping that scans a laser light focusing spot in a photo-curable resin, cures the resin into a desired shape, and can form complex three-dimensional structures in a shorter time than conventional semiconductor processes. The method has been put into practical use and used in fields such as rapid prototyping.

  The processing accuracy of an optical modeling machine currently on the market is about 50 to 100 μm, and development of a micro optical modeling technique is being promoted with the aim of producing a finer three-dimensional structure.

  In the optical modeling technique, the size of the cured portion of the photo-curable resin is determined by the diameter of the focused spot of the laser beam.

  Therefore, a fine structure can be manufactured by focusing light on a smaller area with an objective lens having a high light collecting ability (that is, a large NA) or the like (see Non-Patent Documents 1 and 2 below). However, actually, even if the light is focused by the objective lens, photocuring does not occur only at the focused spot, and a curing reaction occurs around the focused spot, and this excessive growth leads to poor modeling accuracy.

  Therefore, a modeling accuracy improvement method using two-photon polymerization induced by femtosecond laser pulse irradiation for finer optical modeling has been reported (see Non-Patent Documents 3 and 4).

The above-mentioned conventional micro stereolithography technology is disclosed in the following Patent Documents 1-4.
JP 2003-025295 A JP 2001-158050 A JP 7-329188 A JP 2003-001599 A Makoto Moriyama, Hong-Bo Sun, Masafumi Miwa, Shigeki Matsuo, and Hiroaki Misawa, Japan Journal of Applied Physics 38, pp. L212-L215 (1999). Shoji Maruo and Koji Ikuta, Applied Physics Letters 76, p. 2656 (2000). Shoji Maruo, Osamu Nakamura, and Satoshi Kawata, Optics Letters 22, p. 132 (1997). Hong-Bo Sun, Takeshi Kawakami, Ying Xu, Jia-Yu Ye, Shigeki Matsuo, Hiroaki Misawa, Masafumi Mikawa, and Reizo Kansetsu, Op. 1110 (2000).

  As described above, the reason why it is difficult to increase the modeling accuracy in the one-photon process is that light absorption occurs in a region other than the focused spot of the laser beam, that is, a region outside the scanning locus of the focused spot, and the photocuring reaction occurs. For it to happen. In general, the photocuring reaction is a threshold reaction, and curing occurs when the amount of light irradiation exceeds a certain threshold. Two-photon polymerization can have high spatial selectivity because the two-photon absorption probability is proportional to the square of the light intensity, and therefore light absorption occurs only in the vicinity of the focused spot.

  Therefore, in order to impart space selectivity to the photopolymerization, the photopolymerization efficiency at the condensing spot of the curing laser light may be increased compared to the surroundings.

  In the present invention, in addition to the curing reaction inducing laser light (in the embodiment, ultraviolet laser light), the reaction promoting laser light having a wavelength different from that of the curing reaction inducing laser light (in the near infrared laser light in the example) is used. By using it, nano-level three-dimensional spatial selectivity can be provided.

  That is, in view of the above situation, the present invention uses nano-level 3 by using a reaction promoting laser beam having a wavelength different from that of the curing reaction inducing laser beam in addition to the photocuring reaction inducing laser beam. It is an object of the present invention to provide a multi-beam microstructure optical modeling method and apparatus using a different wavelength laser beam capable of providing dimensional space selectivity.

In order to achieve the above object, the present invention provides
[1] In a multi-beam microstructure optical modeling method using different wavelength laser beams, a curing reaction inducing laser beam is irradiated into the photocurable resin, and a reaction promoting laser beam having a different wavelength is applied to the curing reaction inducing laser beam. By irradiating the above-mentioned laser light on the photo-curable resin, a photo-curing reaction is induced only in the vicinity of the condensing spot where the two laser lights overlap.

  [2] In the multi-beam microstructure optical modeling method using the different wavelength laser beam according to [1] above, the curing reaction inducing laser beam is a laser beam absorbed in the photocurable resin, and The laser beam for promoting the reaction is a laser beam having a different wavelength that is not absorbed by the photocurable resin.

  [3] The multi-beam microstructure optical modeling method using the different wavelength laser beam according to the above [1] or [2] is characterized by having nano-level three-dimensional spatial selectivity.

  [4] In the multi-beam microstructure optical modeling method using the different wavelength laser beam described in [3] above, the intensity of the curing reaction inducing laser beam is approximately 0.038 to 0.076 μW.

  [5] In the multi-beam microstructure optical modeling method using the different wavelength laser beam according to [3] or [4], the wavelength of the reaction promoting laser beam is approximately 1064 nm.

  [6] In a multi-beam microstructure optical modeling apparatus using a different wavelength laser beam, a curing reaction-inducing laser beam irradiation means having an extremely low light intensity that does not induce a photo-curing reaction, and the curing reaction-inducing laser beam In the state where the resin is irradiated in the resin, the reaction promoting laser light irradiation means for irradiating the same spot as the curing reaction inducing laser light, and the photo curing reaction is caused only in the vicinity of the condensing spot of the curing reaction inducing laser light. It comprises a photocurable resin.

  According to the present invention, the following effects can be achieved.

  (1) Surplus growth in the horizontal direction and the optical axis direction is suppressed, and the modeling accuracy of the microstructure can be significantly improved.

  (2) It can have nano-level three-dimensional spatial selectivity.

  According to the present invention, when a laser beam for inducing curing reaction is irradiated into the resin at a very low light intensity that does not induce a photocuring reaction, the curing reaction is induced by irradiating the same spot with the laser beam for promoting the reaction. The photocuring reaction can be caused only in the vicinity of the condensing spot of the laser beam for use, and the nano-level three-dimensional spatial selectivity can be provided.

  Hereinafter, embodiments of the present invention will be described in detail.

  FIG. 1 is a block diagram of a main part of a multi-beam micro structure stereolithography apparatus using a two-beam micro stereo modeling method according to a first embodiment of the present invention, and FIG. It is a figure which shows a line pattern.

  In FIG. 1, 1 is a glass substrate, 2 is a stage, 3 is an objective lens (40 ×, NA: 0.9), 4 is an ultraviolet laser beam for inducing curing reaction (dotted line), and 5 is a near-infrared laser for promoting reaction. Light (solid line), 6 is a photocurable resin.

  Therefore, the UV laser light for inducing curing reaction (dotted line) 4 is condensed by the objective lens (40 times, NA: 0.9) 3 at the interface between the glass substrate 1 and the photocurable resin 6 and the stage 2 is scanned. On the other hand, the reaction promoting near infrared laser beam (solid line) 5 condensed at the same point as the curing reaction induction ultraviolet laser beam (dotted line) 4 is turned ON / OFF. Here, the photocurable resin 6 is, for example, an acrylic photocurable resin (KC1156A manufactured by JSR Corporation). The curing reaction inducing laser beam 4 is a laser beam that is absorbed by the photocurable resin 6 and has an extremely weak light intensity. The reaction promoting laser beam 5 is absorbed by the photocurable resin 6. It is a laser beam of another wavelength that does not.

  Therefore, as shown in FIG. 2, only when the reaction promoting near infrared laser beam (solid line) 5 and the curing reaction inducing ultraviolet laser beam (dotted line) 4 are irradiated, the photocuring reaction (resin line pattern) is performed. 7) can be confirmed. Here, it is shown that the photo-curing reaction does not occur when only the curing reaction-inducing ultraviolet laser beam (dotted line) 4 is irradiated. However, the irradiation with only the reaction promoting near-infrared laser beam (solid line) 5 is also light. No curing reaction takes place.

  This indicates that a spatially selective photopolymerization reaction can be induced by using two laser beams having different wavelengths.

  FIG. 3 is a system configuration diagram of a multi-beam micro structure stereolithography apparatus using the two-beam micro stereo modeling method according to the second embodiment of the present invention, and FIG. 4 is a diagram illustrating a glass substrate according to the second embodiment of the present invention. It is a figure which shows the scanning electron microscope image of the photocurable resin spot-cured. In FIG. 3, 11 is a curing reaction-inducing ultraviolet laser light source, 12, 13, 16, 18, and 19 are reflecting mirrors, 14, 15, 20, 21, and 25 are lenses, 17 is a reaction-promoting near-infrared laser light source, 22 and 23 are dichroic mirrors, 24 is an objective lens (100 times, NA: 1.35), 26 is a CCD camera, 27 is a monitor device, 31 is a cover glass, 32 is a photocurable resin, and 33 is a photocurable resin. It is a stage.

According to this embodiment, the ultraviolet laser pulse ( wavelength 355 nm, pulse width 0.5 ns) (cured) collected by the objective lens (× 100, NA 1.35) 24 onto the photocurable resin 32 dropped on the cover glass 31 (curing). When the reaction-inducing laser light (dotted line) is irradiated, photocuring occurs at the condensing position of the curing reaction-inducing ultraviolet laser light from the light intensity reaching the threshold value of the photocuring reaction, as shown in FIG. . Next, when continuous irradiation near-infrared laser light (wavelength 1064 nm) (reaction promoting laser light) (solid line) (solid line) is also condensed and irradiated together with the curing reaction-inducing ultraviolet laser light (dotted line), the left side of FIG. As shown in the third row, the photocuring reaction could be induced even with the intensity of the UV laser light for inducing curing reaction that was so weak that the photocuring reaction did not occur by irradiation with only the curing reaction inducing UV laser light (dotted line). It was found that the photocuring reaction with such an intensity below the threshold is not induced by irradiation of the curing reaction inducing ultraviolet laser beam alone or the reaction promoting near infrared laser beam alone.

  As described above, FIG. 2 and FIG. 4 indicate that the present invention can impart space selectivity to the photopolymerization reaction.

  FIG. 5 is a view showing a columnar microstructure manufactured by the present invention. As is clear from this drawing, a columnar microstructure manufactured by a curing reaction-inducing ultraviolet laser beam and a reaction promoting near-infrared laser beam is shown. Compared to the columnar microstructure 42 produced only by the curing reaction-inducing ultraviolet laser light, the microstructure 41 is suppressed from excessive growth in the horizontal direction and the optical axis direction, and the modeling accuracy is remarkably improved. Can be confirmed.

  As described above, according to the present invention, the photo-curing resin is irradiated with ultraviolet laser light (curing reaction-inducing laser light) at an extremely low light intensity that does not induce a photo-curing reaction, and the photo-curing resin is close to the same spot. When infrared laser light (reaction promoting laser light) is applied repeatedly, a photocuring reaction can occur only in the vicinity of the focused spot of the ultraviolet laser light.

  In addition, this invention is not limited to the said Example, Based on the meaning of this invention, a various deformation | transformation is possible and these are not excluded from the scope of the present invention.

  The multi-beam microstructure optical modeling method and apparatus using the different wavelength laser beam of the present invention can be expected to be used for manufacturing various micro devices (chemical chip, biochip, micromachine, etc.).

It is a principal part block diagram of the multi-beam micro structure optical modeling apparatus using the two-beam micro optical modeling method which shows 1st Example of this invention. It is a figure which shows the line pattern of resin formed by the two-beam micro-stereolithography method which shows 1st Example of this invention. It is a system configuration | structure figure of the multi-beam micro structure optical modeling apparatus using the two-beam micro optical modeling method which shows 2nd Example of this invention. It is a figure which shows the scanning electron microscope image of the photocurable resin spot-cured on the glass substrate which shows 2nd Example of this invention. It is a figure which shows the columnar microstructure produced by this invention.

Explanation of symbols

1 Glass substrate 2 Stage 3 Objective lens (40x, NA: 0.9)
4 Ultraviolet laser beam for induction of curing reaction (dotted line)
5 Near-infrared laser light for promoting reaction (solid line)
6,32 Photo-curing resin 7 Photo-curing (resin line pattern)
11 Curing reaction inducing ultraviolet laser light source 12, 13, 16, 18, 19 Reflector 14, 15, 20, 21, 25 Lens 17 Reaction promoting near infrared laser light source 22, 23 Dichroic mirror 24 Objective lens (100 times, NA: 1.35)
26 CCD Camera 27 Monitor Device 31 Cover Glass 33 Stage 41 Columnar Micro Structure Produced with Curing Reaction Inducing Ultraviolet Light and Reaction Promoting Near Infrared Light 42 Columnar Micro Structure Produced with Curing Reaction Inducing Ultraviolet Light Only

Claims (6)

  Both lasers are irradiated by irradiating a curing reaction-inducing laser beam into the photocurable resin, and irradiating the photocurable resin with a laser beam for promoting the reaction of another wavelength superimposed on the curing reaction-inducing laser beam. A multi-beam micro-structure stereolithography method using a different wavelength laser beam that induces a photo-curing reaction only in the vicinity of a focused spot where light overlaps.   The multi-beam microstructure optical modeling method using the different wavelength laser beam according to claim 1, wherein the curing reaction induction laser beam is a laser beam absorbed in the photocurable resin and has an extremely weak light intensity. And the reaction accelerating laser beam is a laser beam having a different wavelength that is not absorbed by the photocurable resin.   3. A multi-beam fine structure optical modeling method using different-wavelength laser light according to claim 1 or 2, wherein the multi-beam micro-light using different-wavelength laser light has nano-level three-dimensional spatial selectivity. Structure stereolithography.   4. The multi-beam microstructure optical modeling method using different wavelength laser light according to claim 3, wherein the multi-beam laser light having different wavelength laser light having an intensity of about 0.038 to 0.076 [mu] W. Light beam microstructure optical modeling method.   5. The multi-beam microstructure optical modeling method using the different wavelength laser beam according to claim 3 or 4, wherein the multi-beam microstructure light using the different wavelength laser beam having a wavelength of about 1064 nm. Modeling method. (A) a curing reaction-inducing laser light irradiation means having an extremely low light intensity that does not induce a photocuring reaction;
(B) means for irradiating the same spot with reaction-promoting laser light in a state where the curing reaction-inducing laser light is irradiated into the photo-curing resin;
(C) a multi-beam microstructure optical modeling apparatus using a different wavelength laser beam, comprising a photo-curable resin that induces a photo-curing reaction only in the vicinity of the condensing spot of the laser beam for inducing the curing reaction .