JP5189925B2 - Lens member manufacturing method - Google Patents

Description

  The present invention relates to a method of manufacturing a lens member provided on the surface of an optical device such as a light emitting element or a light receiving element for the purpose of condensing light. More specifically, the present invention relates to a method of manufacturing a lens member that can be mass-produced in a fixed shape and with accurate dimensions without using a mold such as a mold.

  For example, a lens is formed on the front side of the light emitting element or light receiving element, and the light emitted from the light emitting element is condensed to some extent to emit light in a certain direction, or the light is collected on the light receiving element to increase the light receiving sensitivity. It is generally performed to light. In such a case, since the light-emitting element and the light-receiving element are generally formed by die bonding an LED chip, a photodiode chip, or a phototransistor chip and further wire-bonding, the protection of these chips themselves and the wire bonding portion In order to protect this, it is sealed with a translucent resin. Moreover, since the sealing with the translucent resin is generally performed by molding using a mold, it is easy to form a convex lens portion by forming a recess in the mold. Can be formed above the light emitting surface and the light receiving surface. Even in a photo reflector having both a light emitting element and a light receiving element, generally, the light emitting element and the light receiving element are molded individually or integrally, so that a recess is formed in the molding die. Accordingly, the lens portion can be easily formed on the light emitting surface and the light receiving surface.

  On the other hand, if you want to seal the light emitting element and the light receiving element as one unit, such as a very small photoreflector, but you want to produce a large number of products in small quantities, such as the outer shape changes slightly depending on the usage, you can use mold molding Is not suitable. However, even in such a case, there is a case where it is desired to provide a lens structure on the light emitting surface or the light receiving surface. In this case, a lens member is separately formed and pasted on the light emitting surface or the light receiving surface. Even in this case, if the lens member itself is formed by molding with a mold, it can be formed very easily. However, if the shape of the lens member is slightly changed, it is costly to use the mold. There is a problem.

In order to meet such demands, for example, a method of discharging a certain amount of UV curable resin on a substrate from an inkjet apparatus and irradiating with UV light after a predetermined time has passed, as shown in FIG. Then, a water repellent layer 32 is formed on the outer periphery of the desired region on the substrate 31 and subjected to a water repellent treatment. After a certain amount of UV curable resin 33 is discharged and cured in the desired region, it is separated from the substrate 31. Attempts have been made to peel off and use a spherical lens member (see, for example, Patent Document 1).
JP 2006-30634 A

  As described above, even when a certain amount of the UV curable resin is ejected onto the substrate by the ink jet apparatus, the spread of the UV curable resin on the substrate is not constant, and as shown in FIG. Even if a method of applying water repellent treatment to the periphery of the substrate is used, since the water repellent treatment is applied to the periphery, the diameter of the UV curable resin on the substrate shrinks when the UV curable resin is cured. There is a problem that the lens becomes small and a lens having a constant diameter and height cannot be obtained.

  In either method, the UV curable resin is directly discharged onto the substrate and cured, and it is adsorbed and peeled off from the upper part of the lens. However, the lens is quite in close contact with the substrate and is very thin. Therefore, there is a problem that the lens is easily deformed or damaged. In particular, since the outer peripheral portion of the lens is very thin, it is easily damaged. From this point, there is a problem that the outer diameter of the lens is likely to vary.

  The present invention has been made to solve such a problem, and a lens member having a constant outer diameter and height is manufactured only by application of a resin without molding using a mold for molding. An object of the present invention is to provide a method for manufacturing a lens member.

  In the method of manufacturing a lens member according to the present invention, a pedestal having the same size as the lens to be formed is formed on one surface of a flexible film, and a liquid resin is applied on the pedestal so that the surface has a spherical shape. Then, by curing the liquid resin, a lens member integrated with the pedestal is formed, the lens member is pushed up from the other surface of the flexible film by a pin, and the lens member is adsorbed from the surface. The lens member is separated from the flexible film.

  Here, the flexible film is, for example, a so-called dicing tape that is attached to the back surface of a semiconductor wafer when the semiconductor wafer is singulated into individual chips, and has a stretch if partially pushed up. It means a film that can be sharpened in a shape, and a resin is a material that can transmit light, such as an ultraviolet curable resin (UV resin) or a thermosetting resin, and when applying, It means a material that is liquid and solidifies when cured. The pedestal means a plate-like body having the same size as the lens and a thickness of about 0.04 to 1 mm. Further, the spherical shape is not intended to be a part of a complete sphere, but has a cross section. The shape means a convex shape having an arc.

  In order to form the pedestal on one surface of the flexible film, a mask having an opening having the same size as the pedestal is placed on one surface of the flexible film, and a resin is placed in the opening of the mask. It can be formed by applying by printing and removing the mask after curing of the resin, or forming a template having a recess of the same size as the pedestal, and in each recess of the template, By applying a resin so that the upper surface and the surface of the template are substantially coincident, and sticking the flexible film to the upper surface of the template and curing the resin, and then removing the template It can also be formed.

  According to the method for manufacturing a lens member of the present invention, a pedestal having the same size as the lens is formed on the flexible film, and a predetermined amount of liquid resin is applied on the pedestal by, for example, a dispenser. The liquid resin applied on the pedestal rises spherically on the pedestal due to surface tension. By making the outer diameter of the lens constant and the amount of liquid resin to be applied constant, the height of the spherical surface of the lens is also constant. That is, it is possible to form a lens (convex portion) having both a constant diameter and height very easily.

  Furthermore, the pedestal and the spherical lens formed on the pedestal have good adhesion when the lenses are made of the same material. On the other hand, the pedestal and the flexible film are made of different materials. Since the pedestal is pushed up from the back side of the flexible film with a pin or the like, the pedestal maintains flatness while the flexible film has a high portion of the push-up pin. However, since the other portions try to maintain the original shape, the flexible film other than the portion pushed up by the pins is separated from the pedestal. As a result, it is possible to easily separate only the lens member by a suction jig such as a suction collet, and move it to a required place for bonding. That is, the lens member can be easily separated from the flexible film and attached to a predetermined place while maintaining an accurate shape without causing any deformation or damage to the lens member.

  Next, a method for producing a lens member of the present invention will be described with reference to the drawings. The lens member manufacturing method according to the present invention has a predetermined diameter and a predetermined diameter on one surface of the flexible film 1, as shown in FIG. The pedestal 2 is formed with a resin at a height of, for example, a liquid resin 3a made of substantially the same material as the pedestal 2 is applied on the pedestal 2 so as to have a spherical surface, and the liquid resin 3a is cured. By forming the convex part 3, the lens member 4 integrated with the pedestal 2 is formed, the pedestal 2 is pushed up from the other surface of the flexible film 1 and pushed up by the pins 8, and the lens member 4 is adsorbed from the surface. The lens member 4 is separated from the flexible film 1 by being adsorbed by a collet 9 or the like.

  Next, a detailed description will be given based on a specific example. In FIG. 1, a manufacturing process of one lens member is shown, but actually, a large number of lens members 4 are formed on the flexible film 1, and one by one from the flexible film 1. Separated and used in actual equipment.

  First, as shown in FIG. 1A, a pedestal 2 is formed on one surface of a flexible film 1 with a resin having a predetermined diameter and a predetermined height. The method for forming the pedestal 2 will be described later with reference to FIGS. 2 to 3, and the resin is screen-printed with resin, filled in the recesses of the template in which the recesses are formed in the shape of the pedestal 2 and cured, It can be formed by attaching the flexible film 1 to the surface and separating it from the template. The flexible film 1 is provided with an adhesive on one side, for example, a so-called dicing tape that is attached to the back surface of the semiconductor wafer when the semiconductor wafer is divided into individual chips, and has a thickness of about 50 to 100 μm. A stretchable synthetic resin film can be used. As the resin, a material of the same system as that of the convex portion 3 described later improves adhesion to the convex portion 3, and therefore, for example, an ultraviolet curable resin is preferably used. Resin etc. can also be used. However, in the case of a thermosetting resin, it is necessary to select the relationship so that the flexible film 1 does not deteriorate due to the heating temperature for curing. The thickness of the pedestal 2 varies depending on the use, but is formed to be about 40 to 100 μm, for example. The diameter of the pedestal 2 is also determined according to the size of the lens used, but is formed to have a diameter of about 0.5 to 1 mm, for example.

  Next, as shown in FIGS. 1B to 1D, for example, a liquid resin 3 a made of substantially the same kind of material as that of the base 2 is applied on the base 2 so as to have a spherical surface. . The liquid resin 3a is preferably the same type of resin as the pedestal 2 because the adhesion to the pedestal 2 is improved. As described above, the liquid resin 3a is liquid and has a spherical shape due to surface tension when applied. An ultraviolet curable resin, a thermosetting resin, or the like that solidifies when used can be used. As described above, it is necessary that the flexible film 1 does not deteriorate during this curing, and the ultraviolet curable resin does not deteriorate most of the flexible film 1 when irradiated with ultraviolet rays, and can be easily used. This is preferable because it can be cured. However, a thermosetting resin such as an epoxy resin can be used as long as the flexible film 1 can be cured at a temperature that does not change due to heat in relation to the flexible film. The liquid resin 3a may be applied by applying a certain amount of liquid resin on the pedestal 2, such as a screen printing method or a liquid resin discharging method using a jet apparatus such as an ink jet. FIG. 1 shows a state in which the liquid resin 3a is discharged from the nozzle of the dispenser 7 and adhered to the pedestal 2 and applied on the pedestal 2 by a predetermined amount. At this time, since the resin is liquid and the bottom surface is limited to the area of the pedestal 2, if the amount of the resin is sufficient, the bottom surface is equal to the diameter of the pedestal 2 due to surface tension as shown in FIG. The surface side is formed into a spherical shape.

  Next, as shown in FIG. 1 (e), the lens member 4 integrated with the pedestal 2 is formed by forming the convex portion 3 by curing the liquid resin 3 a by irradiating with ultraviolet rays (UV). Form. When the liquid resin 3a is a thermosetting resin, it is cured by heating to a curing temperature. Due to the surface tension of the liquid resin 3a, the convex portion 3 has a diameter that rises to coincide with the diameter of the pedestal 2, and its height can be arbitrarily set depending on the amount of liquid resin to be applied. However, in the example shown in FIG. 1, the lens member 4 is formed to have a height of, for example, about 0.35 mm, the height combined with the base 2 is about 0.48 mm, and the diameter is about 0.7 mm. .

  Thereafter, as shown in FIGS. 1 (f) to 1 (g), the pedestal 2 is pushed up from the other side (back side) of the flexible film 1 by the push-up pins 8, and from the front side by a suction jig such as a suction collet 9. By adsorbing the lens member 4, the lens member 4 can be separated from the flexible film 1 together with the base 2 and taken up. That is, when the flexible film 1 is pushed up by the push-up pins 8, only the flexible film 1 at that portion extends upward to form a mountain shape, while the lens member 4 is not deformed by a solid material and is flat. Therefore, the flexible film 1 is separated from the end side of the base 2. Therefore, the lens member 4 can be easily separated from the flexible film 1 by being sucked by the suction collet 9 or the like from the surface side, and can be moved to a predetermined mounting place while being sucked by the suction collet 9. .

  A process of attaching the lens member 4 to the optical device is schematically shown in FIGS. That is, for example, an adhesive 6 made of an ultraviolet curable resin or the like is applied in advance to a place where the lens member 4 of the optical device 5 to which the lens member is to be fixed is attached to the surface of a light emitting element or a light receiving element. The lens member 4 transported by the suction collet 9 is pressed onto 6 and the suction of the suction collet 9 is stopped, so that the lens member 4 can be mounted on the adhesive 6. Thereafter, as shown in FIG. 1 (i), the adhesive 6 is cured by irradiating ultraviolet rays (UV), and the lens member 4 and the optical device 5 are integrated.

  A specific method for forming the pedestal 2 on the flexible film 1 shown in FIG. FIG. 2 is a process explanatory view showing an example thereof. For example, as shown in FIG. 2A, a desired pedestal 2 has a desired thickness on the flexible film 1, for example, a desired thickness of about 0.1 mm. A metal mask 11 having a through-hole 11a having a diameter of the lens member 4, for example, about 0.7 mm, is placed on a metal plate such as stainless steel matched to the above. The flexible film 1 and the metal mask 11 are large, and a plurality of through holes 11a are formed in a matrix at regular intervals. In FIG. 2, only the portion of the base 2 is shown. . The through-hole 11 can be accurately formed even with a very small hole diameter, for example, by laser processing.

  Then, as shown in FIG. 2B, the liquid resin 2 a is applied on the metal mask 11, and the metal mask 11 is flattened by the squeegee 12. Thereafter, as shown in FIG. 2C, for example, by irradiating with ultraviolet rays (UV), the liquid resin 2 a embedded in the through hole 11 a of the metal mask 11 is cured, and the base 2 is formed. Thereafter, the pedestal 2 can be formed on the flexible film 1 by removing the metal mask 11.

  FIG. 3 is a diagram showing another example of forming the base 2 on the flexible film 1. That is, first, as shown in FIG. 3 (a), a depth (predetermined height) and a pedestal according to the desired thickness of the pedestal 2 are formed on a metal plate having a thickness of about several millimeters as described above. A template 15 is formed in which a large number of recesses 15a having a diameter (predetermined diameter) matching the diameter of 2 are formed at regular intervals. Then, as shown in FIG. 3B, a liquid resin 2a made of, for example, an ultraviolet curable resin is applied (filled) into the recess 15a by the dispenser 16 or the like so as to substantially coincide with the surface of the template 15. . Then, as shown in FIG.3 (c), the flexible film 1 is stuck to the upper surface of the template 15, and the liquid resin 2a is hardened. Thereafter, the base plate 2 can be formed on one surface of the flexible film 1 by removing the template 15.

  According to the method for manufacturing a lens member of the present invention, since the convex portion is formed on the pedestal using surface tension, the diameter of the convex portion matches the diameter of the pedestal, and the pedestal is a screen. Since it can be formed with an accurate dimension by the concave portion formed on the printing or the template, a lens member with a very accurate dimension can be formed. That is, it is possible to form a lens member having a convex portion having a certain height on a pedestal having a certain diameter by simply applying or applying a predetermined amount of liquid resin without molding with a mold. . As a result, it can be formed very inexpensively. In addition, since a large amount of lens members are formed on the flexible film, the flexible film is separated from the periphery of the pedestal by pushing up from the back side of the flexible film with a push-up pin, and the lens member from the upper surface side. Can be easily separated and mounted by simply adsorbing them with an adsorption collet or the like. As a result, even a very thin lens member can be accurately mounted in a predetermined place such as an optical device in the same shape without damaging the end thereof, and the reliability can be greatly improved.

  In addition, by forming the pedestal using screen printing or a template having a recess, it can be formed on a flexible film with a very accurate dimension and at a low cost.

It is process explanatory drawing which shows one Embodiment of the manufacturing method of the lens member by this invention. It is a figure which shows an example of the method of forming a base on the flexible film of FIG. It is a figure which shows the other example of the method of forming a base on the flexible film of FIG. It is explanatory drawing of the example which forms a lens, without using the conventional metal mold | die.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Flexible film 2 Base 2a Liquid resin 3 Convex part 3a Liquid resin 4 Lens member 5 Optical device 6 Adhesive 7 Dispenser 8 Push-up pin 9 Adsorption collet
11 Metal mask
11a Through hole
12 Squeegee
15 Template
15a recess
16 Dispenser

Claims (3)

  By forming a pedestal of the same size as the lens to be formed on one surface of the flexible film, applying a liquid resin on the pedestal so that the surface has a spherical shape, and curing the liquid resin The lens member is formed integrally with the pedestal, the lens member is pushed up from the other surface of the flexible film by a push-up pin, and the lens member is adsorbed from the surface, thereby the lens member from the flexible film. A method for producing a lens member, wherein   A mask having an opening having the same size as the pedestal is placed on one surface of the flexible film, a resin is applied in the opening of the mask by printing, and the mask is removed after the resin is cured. The method for manufacturing a lens member according to claim 1, wherein the pedestal is formed on one surface of the flexible film.   A template having a recess having the same size as the pedestal is formed, and a resin is applied in the recess of the template so that the upper surface of the template substantially coincides with the surface of the template. The method for producing a lens member according to claim 1, wherein the pedestal is formed on one surface of the flexible film by attaching the flexible film and curing the resin, and then removing the template.

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