A package structure for an optical sensor that enables sensing through reception of light in the ultraviolet wavelength band and converts ultraviolet signals into digital signals, and a method for manufacturing the same.

Abstract

The present invention provides a package structure for an optical sensor that enables sensing through reception of light in the ultraviolet wavelength band and converts an ultraviolet signal into a digital signal, and a method for manufacturing the same. [Solution] The present invention relates to a package structure for an optical sensor that enables sensing through reception of light in the ultraviolet wavelength band and converts ultraviolet signals into digital signals, and a manufacturing method thereof. The package structure is attached to a PCB substrate on which a light-sensing element unit is mounted, and is configured to surround the element unit, exposing the light-receiving portion of the element unit that receives light, and is made of a light-blocking agent made of a material that can block visible light that enters the side of the element unit excluding the light-receiving portion; and a diffusing agent that is attached to the light-receiving portion of the element unit, allows light to diffuse while transmitting it, and is made of a material containing silicon dioxide.

Description

Technical Field

[0001] The present invention relates to a package structure for an optical sensor that enables sensing through reception of ultraviolet wavelengths and converts an ultraviolet signal into a digital signal, and a method for manufacturing the same. More specifically, the present invention relates to a package structure for an optical sensor that enables sensing through reception of ultraviolet wavelengths with an improved structure so as to reduce measurement deviation due to the incident angle of ultraviolet light incident on the optical sensor and minimize changes in sensing sensitivity due to changes in the incident angle, and a method for manufacturing the same, which converts an ultraviolet signal into a digital signal.

Background Art

[0002] A COB (chip on board) type optical sensor in which an optical sensor chip is mounted on the upper surface of a printed circuit board is generally electrically connected to a main board, so electrode pads are formed on the lower surface, and the printed circuit on the upper surface and the electrode pads on the lower surface are electrically connected through through-holes. The electrical connection through the through-hole is made by a hole penetrating the printed circuit on the upper surface and the electrode pads on the lower surface, and the inside of the hole is plated to electrically connect the printed circuit on the upper surface and the electrode pads on the lower surface.

[0003] Such an optical sensor is configured together with a package to ensure light shielding from the outside and reliability of semiconductor characteristics. Conventional optical sensors generate measurement deviation depending on the incident angle of light, the sensing sensitivity changes depending on the change in the incident angle, the absolute amount of light incident on the optical sensor decreases due to an increase in the reflectance on the lens surface provided on the optical sensor, and there are problems of generating noise due to external light and external moisture.

[0004] As a prior art, there is Korean Patent Publication No. 10-2016-0073451.

Summary of the Invention

Problems to be Solved by the Invention

[0005] The present invention was devised to solve the aforementioned problems, and the object of the present invention is to provide a photosensor package structure and a method for manufacturing the same that reduces measurement deviation due to the incident angle of ultraviolet light incident on the photosensor, minimizes changes in sensing sensitivity due to changes in the incident angle, prevents a decrease in the absolute amount of light incident on the photosensor, enables sensing through reception of ultraviolet wavelength band light that blocks ambient light and moisture flowing in from the outside, and converts ultraviolet signals into digital signals.

[0006] The problems to be solved by the present invention are not limited to those described above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description. [Means for solving the problem]

[0007] To achieve the above objective, the photosensor package structure according to the present invention, which enables sensing through reception of light in the ultraviolet wavelength band and converts ultraviolet signals into digital signals, is provided on a PCB substrate on which a light-sensing element is mounted, and is configured to surround the element, but includes a light-shielding agent made of a material that exposes the light-receiving portion of the element and enables the shielding of visible light flowing into the side surface of the element excluding the light-receiving portion; and a diffusing agent made of a material containing silicon dioxide (SiO2) that is provided on the light-receiving portion of the element and enables the light to be transmitted while being diffused.

[0008] Preferably, the present invention further includes a filter unit comprising: a filter portion made of a material that transmits light of a specific wavelength and is laminated on the diffusing agent; and a pad portion provided on the filter portion and positioned opposite the light-receiving portion of the element portion, which relatively reduces the amount of direct light incident on the light-receiving portion.

[0009] The pad portion of the filter unit faces the center of the light-receiving portion, has a smaller area than the area of ​​the light-receiving portion, and may be made of a light-shielding material.

[0010] The present invention is provided between the filter portion of the filter unit and the PCB substrate, and preferably further includes a package dam portion that has a structure surrounding the sides of the light-shielding agent and the diffusing agent, and blocks light flowing into the sides of the diffusing agent.

[0011] Furthermore, the manufacturing method for a photosensor package structure that enables sensing through reception of ultraviolet wavelength band light and converts ultraviolet signals into digital signals according to the present invention may include: a dam formation step in which a mold unit forms a package dam portion in the frame portion of a PCB substrate on which a light-sensing element portion is mounted in a molding process, thereby forming a placement space on the PCB substrate on which the element portion is arranged and which is open on one side; a light-shielding agent formation step in which a mask unit is placed on the package dam portion in a manner that covers the placement space, and a light-blocking material is introduced into the placement space through an inflow slit formed in the mask unit to form a light-shielding agent that surrounds the side surface of the element portion; a coating step in which the mask unit is separated from the package dam portion, a light-transmitting material is introduced into the placement space, and a diffusing agent is laminated onto the light-receiving portion of the element portion; and a filter mounting step in which a filter unit that transmits light of a specific wavelength and reduces the amount of direct light incident on the light-receiving portion is provided on the package dam portion, and the filter portion is laminated onto the diffusing agent. [Effects of the Invention]

[0012] The photosensor package structure and its manufacturing method according to the present invention, which have the configuration described above and enable sensing through reception of ultraviolet wavelength band light and convert ultraviolet signals into digital signals, have a structure in which a light-shielding agent surrounds the side surface of the element portion mounted on the PCB substrate, blocking the inflow of light and moisture to the side surface of the element portion, and a diffusing agent is provided on the light-receiving portion of the element portion and is made of a material that transmits ultraviolet light, thereby passing and diffusing the ultraviolet light incident on the light-receiving portion, thereby reducing the measurement deviation due to the incident angle of ultraviolet light incident on the photosensor, minimizing the change in sensing sensitivity due to changes in the incident angle, preventing a decrease in the absolute amount of light incident on the photosensor, and also having the effect of blocking ambient light and moisture that flows in from the outside.

[0013] The effects of the present invention are not limited to those described above, and other effects not mentioned will be clearly understood by those skilled in the art from the following description. [Brief explanation of the drawing]

[0014] [Figure 1] This is a cross-sectional view illustrating a package structure for an optical sensor that enables sensing through reception of light in the ultraviolet wavelength band according to one embodiment of the present invention and converts ultraviolet signals into digital signals. [Figure 2] This is a plan view of one embodiment of the present invention. [Figure 3] This is a block diagram illustrating a method for manufacturing a package structure for an optical sensor that enables sensing through reception of light in the ultraviolet wavelength band and converts ultraviolet signals into digital signals, according to one embodiment of the present invention. [Figure 4] This is a conceptual diagram illustrating a manufacturing method for one embodiment of the present invention. [Figure 5] This is a diagram illustrating a mask unit for forming a light-shielding agent in a manufacturing method according to one embodiment of the present invention. [Figure 6] This is a diagram illustrating a mask unit for forming a light-shielding agent in a manufacturing method according to one embodiment of the present invention. [Figure 7]This is a diagram illustrating an extended rib used in a mask unit for forming a light-shielding agent in a manufacturing method of one embodiment of the present invention. [Modes for carrying out the invention]

[0015] In order to clarify the understanding of the present invention in the following description, descriptions of known technologies relating to the features of the present invention will be omitted. The following embodiments are detailed descriptions to aid in the understanding of the present invention and are not intended to limit the scope of the rights of the present invention. Accordingly, equivalent inventions that perform the same function as the present invention also fall within the scope of the rights of the present invention.

[0016] Furthermore, in the following description, the same identification symbol means the same configuration, and unnecessary redundant explanations and explanations of known technologies will be omitted. In addition, the following descriptions of each embodiment of the present invention, which overlap with the description of the technology that forms the background of the invention, will also be omitted.

[0017] The following describes in detail, with reference to the attached drawings, a package structure for an optical sensor that enables sensing through reception of light in the ultraviolet wavelength band and converts ultraviolet signals into digital signals, according to one embodiment of the present invention.

[0018] Figure 1 is a cross-sectional view illustrating a package structure for an optical sensor that enables sensing through reception of ultraviolet wavelength band light and converts ultraviolet signals into digital signals, according to one embodiment of the present invention, and Figure 2 is a plan view of one embodiment of the present invention.

[0019] As shown in Figures 1 and 2, a photosensor package structure according to one embodiment of the present invention, which enables sensing through reception of light in the ultraviolet wavelength band and converts ultraviolet signals into digital signals, comprises a light-shielding agent 100 and a diffusing agent 200.

[0020] The light-shielding agent 100 is provided on a PCB substrate on which an element unit for sensing light is mounted, and is configured to surround the element unit 10, and exposes a light-receiving portion 11 that receives light with the element unit 10. The light-shielding agent 100 is made of a substance that blocks visible light, and is capable of blocking light flowing into the side surface of the element unit 10 except for the light-receiving portion 11 thereof.

[0021] The light-shielding agent 100 is made of a material such as an opaque liquid resin having the property of being able to block visible light, and is applied by a diffusing agent provided on the light-receiving portion in a form covering the light-receiving portion 11 of the element unit on the upper surface. The light-shielding agent 100 prevents the inflow of visible light and moisture to the outside of the element unit 10, so that the sensing sensitivity by the element unit does not decrease, and an error can be prevented during light sensing. Here, the light sensed by the element unit means ultraviolet light.

[0022] As shown in FIG. 1, the diffusing agent 200 has a structure laminated on the light-receiving portion 11 of the element unit 10 that receives ultraviolet light, is capable of diffusing while transmitting ultraviolet light, and can be made of a material containing silicon dioxide (SiO2) that can transmit light containing ultraviolet light. When light containing ultraviolet light is incident, the diffusing agent 200 diffuses the light and transmits it to the light-receiving portion, thereby reducing the measurement deviation due to the incident angle of the ultraviolet light incident on the optical sensor and minimizing the change in sensing sensitivity due to the change in the incident angle.

[0023] The diffusing agent 200 is made of an epoxy-based resin, a silicon-based resin, or the like for ultraviolet light transmission and diffusion, and is formed of various substances capable of transmitting light, such as a liquid resin for an optical waveguide, and can prevent a decrease in the absolute amount of light of the ultraviolet light incident on the light-receiving portion.

[0024] An embodiment of the present invention, which enables sensing through reception of ultraviolet wavelength band light and converts ultraviolet signals into digital signals, has a structure in which a light-shielding agent 100 surrounds the side surface of the element portion mounted on the PCB substrate, thereby blocking the inflow of light and moisture to the side surface of the element portion 10. A diffusing agent 200 is provided on the light-receiving portion 11 of the element portion 10 and is made of a material that transmits ultraviolet light, thereby passing and diffusing the ultraviolet light incident on the light-receiving portion. This reduces the measurement deviation due to the incident angle of ultraviolet light incident on the photosensor, minimizes the change in sensing sensitivity due to changes in the incident angle, prevents a decrease in the absolute amount of light incident on the photosensor, and also has the effect of blocking ambient light and moisture that flows in from the outside.

[0025] On the other hand, it is preferable that this embodiment further includes a filter unit 300 and a package dam section 400.

[0026] As shown in Figure 1, the filter unit 300 transmits light of a specific wavelength and allows the amount of direct light to be adjusted, and may consist of a filter section 310 and a pad section 320. The filter section 310 of the filter unit 300 is made of a material that can transmit light of a specific wavelength, i.e., ultraviolet light, and is laminated on the upper surface of the diffuser 200, so that only ultraviolet light is incident on the diffuser 200.

[0027] The filter portion 310 is connected to the pad portion 320, and the pad portion 320 is positioned in contact with the diffuser 200. The filter portion 310 also allows the light-receiving portion 11 of the element to receive only ultraviolet light, and the diffuser 200 scatters the ultraviolet light. Here, the specific wavelength of light transmitted to the diffuser 200 by the filter portion 310 may vary depending on the type of filter portion.

[0028] The pad portion 320 of the filter unit 300 is provided on the filter portion 310 and is positioned opposite the light-receiving portion of the element portion 10. By relatively reducing the amount of direct light incident on the light-receiving portion, it is possible to minimize the measurement deviation of the light sensor, minimize changes in sensing sensitivity, and derive the advantage of preventing errors when the sensor is driven. The pad portion 320 is made of a variety of materials that can block light, and is also made of plated material to reduce the amount of light.

[0029] The pad portion 320 is positioned opposite the element portion 100 and opposite the center of the light-receiving portion 11, and has a smaller area than the light-receiving portion, thereby reducing the amount of direct light while maintaining sensing sensitivity.

[0030] The package dam section 400 is provided between the filter section 310 of the filter unit 300 and the PCB substrate 200, and has a structure that surrounds the sides of the light shielding agent 100 and the diffusing agent 200. By blocking light flowing into the sides of the diffusing agent 200, the structural stability of the light sensor can be ensured, reliability can be increased during sensing, and sensing sensitivity and errors can be prevented due to the inflow of ambient light and moisture.

[0031] The package dam section 400 is configured to support the filter section 310, with the filter section 310 positioned at its upper end (see Figure 1(b)), or it may be provided with an insertion opening 401 at its upper end into which the filter section 310 is inserted (see Figure 1(a)).

[0032] As described above, the light-shielding agent 100 used in this embodiment has a structure that surrounds the side of the element portion 10 excluding the light-receiving portion 11. It is desirable that the height from the PCB substrate is lower than the height from the PCB substrate 20 to the top surface of the element portion, so that the ultraviolet light scattered from the diffuser 200 after passing through the filter portion 310 is smoothly incident only on the light-receiving portion 11 of the element portion.

[0033] The above describes a package structure for an optical sensor that enables sensing through reception of light in the ultraviolet wavelength band and converts ultraviolet signals into digital signals, according to one embodiment of the present invention. Below, a method for manufacturing the package structure for an optical sensor that enables sensing through reception of light in the ultraviolet wavelength band and converts ultraviolet signals into digital signals, according to one embodiment of the present invention, will be described.

[0034] Figure 3 is a block diagram illustrating a method for manufacturing a package structure for an optical sensor that enables sensing through reception of ultraviolet wavelength band light and converts ultraviolet signals into digital signals according to one embodiment of the present invention; Figure 4 is a conceptual diagram illustrating a method for manufacturing one embodiment of the present invention; Figures 5 and 6 are drawings illustrating a mask unit for forming a light-shielding agent in a method for manufacturing one embodiment of the present invention; and Figure 7 is a drawing illustrating an extension rib used in a mask unit for forming a light-shielding agent in a method for manufacturing one embodiment of the present invention.

[0035] As shown in Figure 3, a method for manufacturing a photosensor package structure that enables sensing through reception of ultraviolet wavelength band light and converts ultraviolet signals into digital signals, according to one embodiment of the present invention, includes a dam formation step (step S100), a light-shielding agent formation step (step S200), a coating step (step S300), and a filter mounting step (step S400).

[0036] The dam formation step (step S100) involves forming the package dam portion 400 by a molding process using a mold unit. The dam formation step (step S100) involves forming the package dam portion 400 by a molding process on the frame portion of the PCB substrate 20 on which the light sensing element portion 10 is mounted, thereby creating a space on the PCB substrate where the element portion 10 is placed and one side is open. The dam formation step (step S100) involves realizing the package dam portion 400 using epoxy resin or the like. In this space, a circuit pattern provided on the PCB substrate, which is electrically connected to the element portion, is placed together with the element portion.

[0037] In the light-shielding agent formation step (step S200), the mask unit 500 is placed on the package dam portion 400 in a manner that covers the arrangement space, and a light-blocking material is introduced into the arrangement space through the inflow slit 501 formed in the mask unit 500 to form a light-shielding agent 100 that surrounds the side surface of the element portion.

[0038] The light-shielding agent formation step (step S200), as shown in Figure 4, involves using the mask unit 500 to allow the light-shielding agent 100 to flow into the filling space such that the height of the light-shielding agent 200 from the PCB substrate 20 is lower than the height to the top surface of the element, so that the light-shielding agent 100 does not penetrate the wires connecting the top surface of the element 100 to the circuit pattern. The light-shielding agent formation step (step S200) may further include a curing step in which the light-shielding agent 100, made of light-shielding material, is cured through a curing machine at a predetermined temperature for a predetermined time so that the light-shielding agent 100 surrounds the side surface of the element on the PCB substrate and is stably provided.

[0039] The coating step (step S300) separates the mask unit 500 from the package dam portion 400, allows a light-transmitting material to flow into the arrangement space, and laminates the diffuser 200 onto the light-receiving portion 11 of the element portion 10. In the coating step (step S300), the light-transmitting material is allowed to flow into the arrangement space to form the diffuser 200. By forming the diffuser at the same height as or lower than the package dam portion 400, ultraviolet light is scattered as it passes through the diffuser and transmitted to the light-receiving portion of the element portion. The light-transmitting material allowed to flow into the arrangement space in the coating step (step S300) consists of a liquid resin for optical waveguides, and the step may further include a resin curing step in which the liquid resin for optical waveguides that has flowed into the arrangement space is cured to form the diffuser.

[0040] In the filter mounting step (step S400), a filter unit 300 that transmits light of a specific wavelength and reduces the amount of direct light incident on the light-receiving portion is provided in the package dam portion 400, and the filter portion 310 is laminated on the diffusing material, so that after the element portion passes through the filter portion, only the ultraviolet light scattered by the diffusing material is received and sensed.

[0041] On the other hand, in the light-shielding agent formation step (step S200), the mask unit 500 for forming the light-shielding agent preferably includes a base plate portion 510, a cover portion 520, and connecting ribs 530, as shown in Figures 5 and 6. The base plate portion 510 is placed on the package dam portion 400 by a device that enables towing, and is provided with through holes to allow the light-blocking material to flow into the arrangement space where the light-shielding agent is formed.

[0042] The cover portion 520 has an area corresponding to the light-receiving portion 11 of the element portion, is positioned in a through hole of the base plate portion 510, and forms an inflow slit 501 between itself and the base plate portion 510, protruding toward the light-receiving portion 11 and covering the light-receiving portion 11, thereby preventing the application of the light-shielding agent to the light-receiving portion 11 while allowing the light-blocking material to flow into the arrangement space through the inflow slit 501 in a manner that surrounds the outside of the element portion 10.

[0043] The connecting rib 530 connects the base plate portion 510 and the cover portion 520, and maintains the shape of the inflow slit 501 for the inflow of the light-blocking material into the arrangement space, thereby enabling smooth inflow of the light-blocking material into the arrangement space and stably fixing the cover portion 520 on the upper side of the element portion 10.

[0044] On the other hand, the cover portion 520 may also be provided with a cover groove 521 that prevents the wire 30 from being exposed so as to prevent the wire from being coated with the light-blocking agent when the light-blocking substance flows in. The cover groove 521 is provided in the portion facing the wire and is preferably grooved.

[0045] As shown in Figure 7, the cover portion 520 may also be provided with an extension rib 522 that extends toward the PCB substrate 20 to define the cover groove, along with the formation of the cover groove. The extension rib 522 is provided on the outside of the cover portion and prevents the electric wire from being exposed to the placement space when it is inserted into the cover groove 521. The extension rib 522 is formed inclined toward the inside of the package dam portion so that when the light-blocking material flows into the placement space for the formation of the light-shielding agent, the light-blocking material is not applied to the electric wire, but flows only to the side of the element portion.

[0046] The aforementioned dam formation stage (step S100), light-shielding agent formation stage (step S200), coating stage (step S300), and filter installation stage (step S400) are carried out by a mold unit, traction equipment, a device for injecting liquid material, and a molding device, and are performed by a controller (not shown) that has a built-in program for driving each device. The controller can be implemented as a computer or a dedicated terminal with a built-in program.

[0047] Although various embodiments of the present invention have been described above, these embodiments and the drawings attached herein only clearly illustrate a part of the technical idea contained in the present invention. It is obvious that any modifications and specific embodiments that can be easily inferred by a person skilled in the art within the scope of the technical idea contained in the specification and drawings of the present invention are all included within the scope of the rights of the present invention.

Claims

[Claim 1] The molding unit forms a package dam portion in the frame portion of the PCB substrate on which the light-sensing element portion is mounted during the molding process, thereby forming a dam-forming step in which the element portion is placed on the PCB substrate and an open arrangement space is formed on one side. A light-shielding agent formation step is performed in which the mask unit is placed on the package dam portion in a manner that covers the arrangement space, and a light-shielding material is introduced into the arrangement space through an inflow slit formed in the mask unit to form a light-shielding agent that surrounds the side surface of the element portion. A coating step in which the mask unit is separated from the package dam section, a light-transmitting material is introduced into the arrangement space, and a diffusing agent is laminated onto the light-receiving portion of the element section, A filter unit is provided in the package dam section to transmit light of a specific wavelength and reduce the amount of direct light incident on the light-receiving portion, and the filter section is laminated on the diffusing material in a filter mounting step. A method for manufacturing a package structure for an optical sensor that enables sensing through reception of light in the ultraviolet wavelength band and converts ultraviolet signals into digital signals.

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