TW594056B - Manufacturing method of focusing and photosensitive micro-lens array - Google Patents

Abstract

The manufacturing method of focusing and photosensitive micro-lens array mainly includes the followings: (1) preparation step; (2) exposure formation step; (3) conduction layer formation step; (4) duplicating and reproducing mold step; (5) micro-lens formation step; and (6) product step. In the invention, near-approaching exposure method of optical lithography is used such that a predetermined gap is formed between the mask and the photoresist layer, and the micro-lens array is formed after exposure and development. After that, electroforming is conducted to form mold for mass production. The invention is capable of providing high precision and low production cost. In addition, the manufacturing process is stable and its application range is wide. In particular, by using different separation portions to make UV light source generate different diffraction phenomena, and using different separation distances to irradiate photoresist layer to generate micro-lens array with specific geometrical, the invention can be applied in various scientific products of micro-meter domain.

Description

594056 V. Description of the invention (1) [Technical field to which the invention belongs] The present invention relates to a method for manufacturing a focusing and photosensitive microlens array, in particular to a method for manufacturing a focusing and photosensitive microlens array, which has both high precision and production The advantages and effects of low cost, stable process and wide range of applications; especially 'different diffraction of ultraviolet light sources with different intervals, and irradiation of photoresist layers with different intervals to produce microlens arrays with specific geometric shapes , Can be applied to a variety of micron technology products. [Previous technology], As one of the micro lens array manufacturing methods, as shown in Figures 12 and 13, one hundred lithography (lithography) technology is used to form at least one rough columnar shape on a phantom 100. Model 101, the diameter of each approximately cylindrical model may only be 120 micrometers, Xi 尨 ^, Minato, A 丄 such as-and then through a heating device 102 to the model 仃 ", fused ( thermal ref i〇w) process, so that the arc-like shape required by the surface tension type 101 is formed. However, it is difficult to control the arc-like shortcomings of the model 101 after thermal dazzling by using this: As a result, serious snail points such as high defect rate and unstable process cannot meet the requirements of the industry. However, those who use micro-lens to make micro-lenses are limited to the precision of micro-lenses formed by this method. Another known technology is semiconductors; process equipment == those with newer-type micro-lens arrays, although this method is not in line with the industry: To :: However, the production cost is too high and the process is complicated. It is necessary to develop new technologies to address these shortcomings. Page 5 59 4056 V. Description of the invention (2) [Summary of the invention] The main purpose of the present invention is to provide a method for manufacturing a focusing and sensor lens array, which has high precision and low production cost, and eliminates the lack of miscellaneous problems. The purpose is to provide a manufacturing method of focusing and sensing lens array, which has a stable manufacturing process and is difficult to control conventional molds. It is not easy to control the precise size of the finished micro lens. Another object of the present invention is to provide a manufacturing method of focusing and sensing lens array. Wide range of applications. It can be used in displays, making optical lenses, improving optical signal focusing of optical fibers, optical systems, endoscopes for medical biotechnology, and various micron applications. Please refer to the second to third figures of the microlens array of the above-mentioned type, and the manufacturing methods are as follows: a photomask 20, a spacer 30, a photoresist layer 40, and a base ultraviolet light source 60 (see the fourth figure for cooperation) ), A conductive film 70 (see the ninth figure), a mold body 80 and a mold 90. Among them: the photomask 2 0 'is located on the top of each element, mainly shielding purple 6 In order to prevent direct exposure to each element, the photomask 20 has a plurality of rows of light-transmitting holes 21 ′ which penetrate the photomask 20 and are equilaterally distributed to each other; the spacer 30 is provided on the photomask The photoresist layer 40 having a predetermined thickness between the photoresist layer 40 and the photoresist layer 40 can be set to the photoresist layer 40 of the photomask 20 and the photoresist layer 40, and the main system receives an ultraviolet light source 6 to pass through the transmissive micro-transmission. The lack of mold-making multi-light micro-transparent hot-melt process. The light-micro-transparent light guide plate alignment system is used. Manufacturing method. Prepare the main package 50, one (coordinate with the regular external light source in a regular row of triangles, with a pre-spacing d; Light hole 2 1 photo

Page 6 594056 V. Explanation of the invention (3) The recess 50 is formed on the surface by irradiating the ultraviolet light source 60. The base 50 is provided on the bottom surface of the photoresist layer 40 to strengthen the structure of the photoresist layer 40. The The conductive film 70 is disposed on the upper end surface of the photoresist layer 40 and forms the recess 41 (see the sixth figure);

The body 80 is formed on the conductive film 70 (see FIG. 8). The structural strength of the conductive film 70 is improved by the mold body 80. After the mold body 80 is set, the light is removed. Resist layer 40 and base portion 50. Of course, once the conductive film 70 and the mold body 80 are formed, the mold 90 is formed on the end surface of the conductive film 70 which is different from the mold body 80, which is known in the industry and will not be described in detail; When in use (see Figure 10), it can be integrally molded to produce a high-precision microlens 91 (see Figure 11). Regarding the manufacturing method, in the first embodiment, as shown in the first figure, it includes the following steps: 1. Preparatory step 11, 2. Exposure molding step 12, 3. Conductive layer molding step 13, 4. Copy Steps 14, 5 and 5 of the micro-lens forming step 6 and the finished product 16 are detailed as follows:

I. Preparatory step 11: Prepare a photomask 20, which is shielded by the photomask 20 to prevent the ultraviolet light source 60 from directly irradiating each component, and the ultraviolet light source 60 is transmitted through the light transmission hole 21 of the photomask 20 The photoresist layer 40 (see the fourth and fifth figures); 2. Exposure molding step 12: Adjust the exposure distance d between the photomask 20 and the photoresist layer 40 (that is, adjust the interval portion 30), and act as an ultraviolet light source. 60 When the light-transmitting hole 21 is irradiated to the photoresist layer 40 through the spacer 30, the spacer is provided.

594056 V. Description of the invention (4) 30 causes the "diffraction phenomenon" of the ultraviolet light source. The light beam of this diffraction phenomenon presents an intensity distribution state with a strong central point and gradually weakening surroundings, and the photoresist layer 40 is affected by This " diffraction phenomenon " is irradiated by the ultraviolet light source 60, that is, a semicircular curved surface recess 41 having a deep middle and a light surrounding is formed at the place where it is illuminated, and the recess 41 is a small circular curved surface formed by El is gradually enlarged, finally formed into a semicircular curved surface e2, and has an extremely smooth surface. 3. Conductive layer forming step 13: After the concave portion 41 of the photoresist layer 40 is formed, the ultraviolet light source 60 and the photomask 20 are removed ( (Refer to the sixth figure), and after forming a conductive film 70 with a predetermined thickness on the surface of the photoresist layer 40 forming the recess 41 (φ refer to the seventh and eighth figures); ^ ψ); This series: after shooting with two plastics, of course, the eleventh figure is ready. The fourth step is to copy the mold. 4: 80 (see the seventh and eighth figures) ^ Remove (see the ninth figure). Body 80 You can form a mold 90, the same mold 90, and become a mold group. Micro lens forming step 15 v — plastic injection molding machine, which can be produced (see the tenth figure), 6. Finished product step 16: Yu Cheng finished the micro lens 91 finished product (refer to the course, the present invention is in the manufacturing method A mold body with an electro-membrane 70 is electroformed on the surface of the photoresist layer 40 and the base 50. Another corresponding mold-clamping industry knows the details of the corresponding mold-clamping industry. A micro-lens 91 can be manufactured by hot-pressing molding method. Open the mold 90, and you can take it out.) The part of step 11 includes the angle again. The light-transmitting hole 21 of the mask 20 is shaped like this. The distribution pattern, as shown in the light transmission diagrams, shows the center-to-center center distance of the equilateral regular three.

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It is defined as P, and the apertures are both D. The distance between the spacers 30 must match the microlenses 91 ', and the adjustment is applicable to the production of various different fields. Therefore, the present invention is implemented in practice. The different distance d in the portion 30 irradiates the photoresistive external light source 60. In practice, the farther the distance d of light is, it represents the recess 41 formed by the light center 60 on the photoresist layer 40. Figure (:, Figure £, Figure 0 is an enlarged plan view of the 240, 360, 720, and 840 microarrays, and Figures B, A to A, C, E, and G are regular distributions of the light transmitting holes 21; That is, to produce a better relative distance between d and P, it is a phase microlens 91. The principle of diffraction is used, and the spacer layer 40 is subjected to a different "diffraction state" of the purple resist layer 40 and the ultraviolet light source 60 is irradiated. The weaker the light source is, the shallower the relative ultraviolet light source is. As shown in Annex 1, the lens D, F, and Η generated by the line light source 60 penetrating the mask 20 with different distances d (meters) correspond to the surface in order. Outline.

Take Figure A and Figure B as an example. Figure A is a lens array formed by the ultraviolet light source 60 on the photoresist layer 40 with a basic d-2P (2xl20 microns = 240 microns) pitch relationship (see attachment ^ 1 for details). ) 'And Figure B clearly shows that the recess 41 has a semi-circular curved surface with a large radius, and then take Figure g as an example, and Figure G is the pitch relationship of the ultraviolet light source 60 at d = 7 P (7xl20 microns = 840 microns). A lens array formed by irradiating the photoresist layer 40 underneath. Comparing figure η with figure B, the radius of the recess 41 of figure Η is significantly smaller than that of figure B; therefore, during the exposure molding step 12 of the present invention, the mask 20 can be changed by adjusting the spacer 30 With the distance d from the photoresist layer 40, by using such an adjustment mechanism, microlenses with a specific geometric shape and focus can be manufactured for industrial use.

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V. Description of the invention (6) In summary, the advantages and effects of the present invention can be summarized as follows: [1] High precision and low production cost. The present invention uses the principle of focusing and light sensing to fully use the principle of diffraction of light, so as to form specific recessed portions on the photoresist layer, and after precise forming, coupled with the mold forming of the electroforming method, it can be produced, that is, the conventional use is eliminated The problem of hot-melt technology cannot precisely control the shape of micro-lenses. In addition, the present invention accepts light in a "close-to-close exposure" manner to form a recess on the surface of the resist layer, so the distance between the photomask and the resist layer, the size and distribution of the penetration holes, etc. can be relatively accurately calculated by accurate numbers. The precise control of the formation of the recessed portions further achieves high precision and low production costs. [2] The process is stable. The present invention cooperates with an ultraviolet light source to irradiate through the photoresist through its fine transparent holes to gradually form a recessed portion on the surface of the photoresist layer. The concave ^ ^ is smooth and can be accurately controlled. After that, electroforming and refining a large number of mold sets for hot pressing or injection, so the microlenses can be mass-produced and the process is stable. [3] Wide application range. And because this creation uses "close-up exposure" to control the size of the microlenses, it can be used in a wide range of applications. Therefore, the light guide plate of the display, fiber optic components, or endoscopes for biomedicine and other fines:

It can be used in various fields. In particular, the micro lens array formed by this technology has a focusing function. Therefore, I is used in the field of optical lenses for imaging and vision. The above, ",,, and above are only a detailed description of the present invention through the preferred embodiments. Any simple modifications and changes made will not depart from the essence of the present invention. The detailed description will enable those skilled in the art to understand the possibilities of the present invention. Reaching the stated purpose, it has indeed met the provisions of the Patent Law, Mai proposed an invention

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Lens Array Generated by Photomasks with the Same Pitch Figure 594056 Lens Array Generated by the Photomask with Pitches 5. Description of Invention (7) Patent Application. [Attachment 1] Figure A is an enlarged top view of a UV light source penetrating through a column. Figure B is an external plan view of a lens surface of Figure A. C is an enlarged top view of a UV light source penetrating through different columns. Enlarged top view of lens array generated by ultraviolet light source penetrating through reticle with different pitches. Fig. 3 is F. Figure E is a lens surface outline drawing. Fig. G is an enlarged plan view of lens array produced by ultraviolet light source penetrating reticle with different pitches. Lens surface outline drawing [Annex 2] Scanning electron microscope outline photo of micro lens array made with 240 micron pitch

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[Brief description of the drawings] The first diagram is a flowchart of the manufacturing method of the present invention, the second diagram is a schematic diagram of the manufacturing apparatus of the present invention, the second diagram is an enlarged top view of a part of the second diagram, and the fourth diagram is a schematic diagram of the manufacturing process of the present invention. A fifth diagram is a schematic diagram of the manufacturing process of the present invention. A second sixth diagram is a schematic diagram of the manufacturing process of the present invention. A third seventh diagram is a schematic diagram of the manufacturing process of the present invention. A fourth and eighth diagram are schematic diagrams of the manufacturing process of the present invention. Schematic diagram of the manufacturing process of the invention. The tenth diagram is a diagram of the manufacturing process of the present invention. The sixth and eleventh diagrams are microscopic diagrams of the microlenses of the present invention. The twelfth diagram is a schematic diagram of a conventional microlens manufacturing method. The thirteenth diagram is a conventional diagram. Schematic diagram of micro lens manufacturing method 2 Preparatory steps 11 Exposure molding step 12 Conductive layer molding step 13 Copy and flip step 14 Micro lens molding step 15 Finished product 16 Photomask 20 Light transmission hole 21 Photoresist layer 4 0 Base 50 Conductive film 70 Mold 90 Mold Body 100 Heating equipment 1 0 2 Spacer 30 Recess 41 UV light source 60 Phantom 80 #Lens 91 Mould 101

594056 Brief description of the diagram P pitch P Pitch d Semicircular surface e: Aperture D Small circular surface e 1

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Claims (1)

W4056 6. Scope of patent application A method for manufacturing a focusing and photosensitive microlens array, including the following steps: The following steps a. Preparatory steps: preparation-a photomask, which is completely illuminated by the external light source, the photomask has a plurality of penetrating cyanosis A space is provided between the photoresist layer and the photoresist layer for the ultraviolet light source to penetrate and irradiate, wherein the space is two, the distance is equal to the center of the light transmission hole, Position of the center of the circle 1. Exposure molding step: The photoresist layer is irradiated with an ultraviolet source introduced through the light-transmissive hole, that is, the light ^ = the concave portion; the predetermined ^ conductive layer forming step · The concave portion of the photoresist layer is formed into a band Deyuan and the first cover, and the first resistance layer shape = *, two should ;: electrical weft formation on the conductive film-mold, microlens forming step: forming a micro by hot pressing or injection on the two molds Lens; then 2 can 4 this = step: after the micro lens is formed, open the mold, that is, one of the focusing and photosensitive micro-transmitters described in item 1 of the lens enclosure, and the plurality of light-transmitting holes of the mask are used for light. Hood ΐ ί Angular type distribution. One of the focusing and photosensitive micro-transmissions described in item 1 of the monthly reference page 14 594056 6. Patent application scope The exposure interval between layers to make various microlens sizes. 4. The manufacturing method of the focusing and photosensitive microlens array according to item 1 of the scope of patent application, wherein after a mold body is electroformed on the surface of the conductive film, the photoresist layer and the base are removed to form a mold. A mold corresponding to the corresponding mold is produced to form a mold group. 5 · According to the manufacturing method of the focusing and photosensitive microlens array described in item 1 of the scope of patent application, the bottom surface of the photoresist layer is provided with a base for improving the structural strength. Page 15