JP5436866B2 - Lens forming method - Google Patents

Description

  The present invention relates to a lens forming method, and more particularly to a lens forming method for forming a lens for mounting on a predetermined surface of an optical semiconductor package (device) or the like without using a mold.

  Conventionally, a lens is mounted on, for example, an optical semiconductor package used for a remote controller or the like. In this optical semiconductor package, a method of forming a lens at the same time as the resin sealing of the main body, A method of sticking a lens formed of a mold to a mounting surface of an optical semiconductor package has been adopted.

  Further, as a method for forming a microlens on a substrate or the like without using a mold, there are the following Patent Documents 1 and 2, which are disclosed in Patent Documents 1 and 2 by an inkjet method or the like. It is disclosed that a microlens is formed by discharging a resin droplet and curing the droplet.

JP 2006-30634 A JP 2006-323146 A

  However, in the conventional method of forming a lens using a mold, a mold having a high-precision R shape is required. This mold is expensive, and the recent optical semiconductor package (device) is small. Therefore, there is a problem that it is difficult to form a lens using a mold.

On the other hand, in the case of a method that does not use a mold, as disclosed in Patent Documents 1 and 2, a process for imparting water repellency to the lens forming surface is required.
That is, FIG. 3 shows a state after the conventional liquid repellent treatment (Patent Document 1). As shown in the figure, liquid repellency is obtained around the microlens formation region 12 on the substrate 11. A self-assembled film 13 is formed, and the resin 14 is dropped onto the microlens formation region 12 to prevent the resin 14 from spreading. Such liquid repellent treatment can also be performed by plasma treatment or the like.

  However, the treatment for obtaining such water repellency (liquid repellency) has a disadvantage that the manufacturing process is complicated and multi-step. In addition, when high accuracy is required for the lens shape, it is possible to selectively treat the water-repellent part by using photolithography or masking, but in this case, expensive equipment must be used. There is a problem that must be.

  The present invention has been made in view of the above problems, and its purpose is to use a lens without using an expensive mold, and without requiring a complicated process or expensive equipment for water-repellent treatment. It is an object of the present invention to provide a lens forming method that can be manufactured easily and inexpensively.

To achieve the above object, a lens forming method according to the present invention, the vacuum evacuation, a sheet on the pin resilient with angular adsorbed between the upper and side surfaces, the push-up the sheet from below By forming a state, a pedestal having a corner on the outer peripheral edge is formed on the sheet, and the liquid resin is applied in a substantially hemispherical shape on the pedestal, and then the substantially hemispherical liquid resin is cured. Thus, the lens is formed, and then the push-up state by the pin is released.
According to the invention of claim 2, a pin having an angle between the upper surface and the side surface is raised toward an elastic sheet, and the sheet is pushed up from below, so that the outer peripheral edge is placed on the sheet. A pedestal with a corner is formed, and a liquid resin is coated on the pedestal in a substantially hemispherical shape, and then a lens is formed by curing the substantially hemispherical liquid resin, and then pushed up by the pin. The state is released.
The invention of claim 3 is characterized in that after releasing the push-up state by the pin, the lens on the sheet is picked up by a pickup device and placed on the mounting portion of the optical semiconductor device via an adhesive.

  According to the configuration of the present invention, for example, by forming a circular shape with the upper surface being a flat surface or a spherical concave surface, the elastic sheet is pushed up with a pin having a corner formed on the edge of the circular upper surface, thereby protruding on the sheet. A circular pedestal is formed, and when the liquid resin is dropped onto the pedestal, the liquid resin is applied in a spherical shape by surface tension. Next, a lens is formed by irradiating the spherical liquid resin with, for example, ultraviolet rays. In such a production, the convex pedestal exhibits the same effect as the water-repellent treatment due to the presence of the rounded circular edges, and prevents the liquid resin from spreading out to a desired circumference. And a lens having a spherical shape (curvature) can be formed.

  The formed lens is picked up by a pickup device such as a suction collet and mounted on an optical member such as an optical semiconductor package via an adhesive, thereby being assembled into the optical semiconductor package or the like.

  According to the present invention, a lens can be manufactured at low cost without using an expensive mold, and a complicated process such as a plasma process for water repellency treatment, an expensive process for performing photolithography, masking, or the like. No equipment is required, and the lens can be manufactured easily and inexpensively.

It is a figure for demonstrating each process of the lens formation method which concerns on the Example of this invention. It is a figure which shows two structure [FIG. (A), (B)] of the multi-pin juxtaposed member used for an Example. It is a figure for demonstrating the water-repellent process in the conventional lens formation.

  FIG. 1 shows the steps of a lens forming method according to an embodiment of the present invention, and FIG. 2 shows the configuration of an apparatus for obtaining a sheet push-up state in the embodiment. In the embodiment, as shown in FIG. 1A, an elastic sheet (or tape) 1 having a thickness of about 50 μm and made of silicone rubber, vinyl chloride, and Teflon (registered trademark) is shown in FIG. As described above, the plurality of pins 2 for pushing up (for setting the base) are arranged side by side while projecting, and the multi-pin juxtaposed member 4 configured to be evacuated from the gap 3 between the pins 2 (or 4b), and the plurality of pins 2 have a circular (or other shape) upper surface as shown in FIG. 2A, or a flat (or substantially flat) upper surface, or FIG. ) (The pin 2b) whose upper surface is a spherical concave surface is used. With such a flat or spherical concave upper surface, in the pins 2 and 2b of the embodiment, an angle is formed between the circular upper surface and the side surface. An effect will be obtained.

  In the embodiment, the elastic sheet 1 and the multi-pin juxtaposed member 4 are used to form a lens and mount it on a semiconductor package. This manufacturing process is shown in FIG. )explain.

  First, as shown in FIG. 1A (push-up process), when a pin 2 is arranged on the lower side of a flatly spread sheet 1 and the side surface side of the pin 2 is evacuated, as shown in FIG. Then, a thin and elastic sheet 1 is sucked, and this sheet 1 is pushed up while being in close contact with the flat upper surface of the pin 2, and a pedestal (convex top) F with the sheet 1 interposed on the upper surface of the pin 2 is formed. It is formed. This pedestal F becomes a circular pedestal F having corners on the outer peripheral edge by being pushed up on the upper surface of the pin 2.

  1C, a predetermined amount of liquid ultraviolet (UV) curable resin 5 is dropped and applied to the base F using a dispenser or the like. The dropping and coating are performed by a potting method, a printing method, a jet method, an ink jet method, or the like. The liquid resin 5 remains in the cornered base F (inside the outer peripheral circular edge) and forms a substantially hemispherical body by its surface tension in a state where wetting spread is suppressed.

  In the next UV irradiation process of FIG. 1D, the liquid resin 5 is cured and the lens 50 is formed by irradiation with ultraviolet rays. Thereafter, as shown in FIG. 1E, the pushing-up state is canceled by stopping the vacuum exhaust, and the sheet 1 returns to a flat state.

  Next, in the lens mounting process of FIGS. 1 (F) to 1 (H), as shown in FIG. 1 (F), the suction collet (which is sucked by negative pressure control in the cylindrical rod) 6 as the pickup device is attached to the lens 50. The lens 50 is picked up from the sheet 1 as shown in FIG. 1G by pushing up the pin 7 from the lower side of the sheet 1 at the same time as being sucked by the suction collet 6. It is peeled off. Thereafter, as shown in FIG. 1H, the lens 50 is transferred by the suction collet 6, and this lens 50 is placed on the mounting portion of the optical semiconductor package 8 via the adhesive 9. 8 completes the assembly of the lens 50.

  In FIG. 1, the upper surface of the pin 2 is a flat surface. However, as shown in FIG. 2B, a pin 2b (multi-pin juxtaposed member 4b) having an upper surface having a spherical concave surface (concave spherical surface) may be used. According to the above, the angle between the circular upper surface and the side surface of the pin 2b can be made an acute angle, and the effect of suppressing the wetting and spreading of the liquid resin 5 applied to the base F can be enhanced.

  In the above-described embodiment, the sheet 1 is pushed up by evacuation. However, it may be configured such that each pin is supported so as to move up and down and the pin 1 is raised to push up the sheet 1.

  The present invention can be applied not only to an optical part of an optical semiconductor package used for a remote controller or the like, but also to an optical part used for various devices such as an imaging device and a detection device.

1 ... sheet, 2,2b, 7 ... pin,
4, 4b ... multi-pin juxtaposed member,
5 ... Liquid resin, 50 ... Lens,
6 ... Adsorption collet, 8 ... Optical semiconductor package,
9: Adhesive, F: Pedestal.

Claims (3)

The vacuum exhaust is adsorbed an elastic sheet to a pin having a corner between the top surface and side surfaces, by a state of pushing up the seat from below, on the sheet, with the angular outer peripheral edge Forming a pedestal,
A liquid resin is applied in a substantially hemispherical shape on this pedestal,
Next, a lens is formed by curing the substantially hemispherical liquid resin,
Then, the lens formation method which cancels | releases the pushing-up state by the said pin. A pin with a corner between the upper surface and the side surface is raised toward the elastic seat, and the seat is pushed up from below, thereby forming a pedestal with a corner on the outer periphery on the seat. Forming,
A liquid resin is applied in a substantially hemispherical shape on this pedestal,
Next, a lens is formed by curing the substantially hemispherical liquid resin,
Then, the lens formation method which cancels | releases the pushing-up state by the said pin . 3. The lens according to claim 1, wherein after the push-up state by the pin is released, the lens on the sheet is picked up by a pickup device and placed on the mounting portion of the optical semiconductor device via an adhesive. Forming method.

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