KR20160137815A - Method for Forming Light Blocking Layer of LED Chip - Google Patents

Method for Forming Light Blocking Layer of LED Chip Download PDF

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Publication number
KR20160137815A
KR20160137815A KR1020150071554A KR20150071554A KR20160137815A KR 20160137815 A KR20160137815 A KR 20160137815A KR 1020150071554 A KR1020150071554 A KR 1020150071554A KR 20150071554 A KR20150071554 A KR 20150071554A KR 20160137815 A KR20160137815 A KR 20160137815A
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KR
South Korea
Prior art keywords
led chip
light
light blocking
droplet
composition liquid
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Application number
KR1020150071554A
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Korean (ko)
Inventor
강동성
이정우
김진구
진도화
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(주)위시스
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Priority to KR1020150071554A priority Critical patent/KR20160137815A/en
Publication of KR20160137815A publication Critical patent/KR20160137815A/en

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L33/00—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L33/44—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the coatings, e.g. passivation layer or anti-reflective coating
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L33/00—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L33/005—Processes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/10—Details of semiconductor or other solid state devices to be connected
    • H01L2924/11—Device type
    • H01L2924/12—Passive devices, e.g. 2 terminal devices
    • H01L2924/1204—Optical Diode
    • H01L2924/12041—LED

Abstract

The present invention relates to a method for forming a light blocking layer, in which the light blocking layer capable of blocking light emitted to the side surface of a LED chip is formed on the side surface of the LED chip. The method according to the present invention comprises the steps of: (a) disposing a pump head, which includes a storage part in which light blocking solution is stored, a nozzle disposed under the storage part, and an upper electrode disposed to be submerged into the light blocking solution, and an lower electrode disposed under the pump head; (b) disposing a LED chip on the lower electrode so that an outer periphery of the LED chip faces the pump head; (c) generating a potential difference between the upper electrode of the pump head and the lower electrode so as to apply the light blocking solution to the side surface of the LED chip in a direction perpendicular to the side surface of the LED chip and discharging the light blocking solution as a first droplet toward the side outer periphery of the LED chip through the nozzle; (d) discharging a second droplet of the light blocking solution onto the first droplet by using the pump head; (e) hardening the first and second droplets of the light blocking solution applied on the side surface of the LED chip so as to form a light blocking layer on the side surface of the LED chip.

Description

TECHNICAL FIELD [0001] The present invention relates to a method of forming a light blocking layer of an LED chip,

The present invention relates to a method of forming a light shielding film of an LED chip, and more particularly, to a method of forming a light shielding film on an LED chip, which is capable of blocking light emitted to a side surface of the LED chip, To a method of forming a light blocking film of a chip.

Generally, an LED element is manufactured by cutting an LED chip manufactured on a wafer and forming a fluorescent layer thereon. The LED chip usually emits blue or red light. When a fluorescent material containing a fluorescent material is applied to the LED chip, the color produced by the LED device varies depending on the amount of the fluorescent material. By emitting an appropriate amount of the fluorescent liquid to the LED chip, it is possible to manufacture white light or various other LED elements of various colors.

An example of an LED element manufacturing apparatus is disclosed in Korean Patent Laid-Open Publication No. 2013-0081029. The LED element manufacturing apparatus disclosed in the above publication dispenses a phosphor-containing liquid resin with a predetermined discharge amount in an LED package and adjusts a discharge amount of the phosphor-containing liquid resin so that the target color coordinate is obtained based on a target color coordinate value (CIE rank) Thereby manufacturing an LED element.

The color coordinate value of the LED element can be adjusted by controlling the amount of the fluorescent liquid to be dispensed for each LED chip in the manufacture of the LED element. In order to adjust the color coordinate value of the LED element by controlling the amount of the fluorescent agent, it is necessary to precisely control the amount of the fluorescent agent in a very small unit. Recently, miniaturization of the size of the LED chip has been demanded, and a technique capable of applying a small amount of a fluorescent fluid to the LED chip in a predetermined amount is required.

In addition, in order to improve the optical quality of the LED element, in addition to a technique of applying a predetermined amount of the fluorescent material to the LED chip, the technology of shielding the light emitted to the side of the LED chip is becoming more important. When the light emitted from the LED chip is emitted to the side of the LED chip, the color coordinate value of the light emitted to the front surface changes and a yellow ring appears.

In order to solve such a problem, a technique has been disclosed in which a light shielding film is formed by applying a light shielding composition liquid to a side surface of an LED chip with a dispensing device to shield light emitted to the side of the LED chip. However, in the conventional method using the dispensing device, it is not easy to form a light shielding film by coating the side surface of the LED chip with a light shielding composition liquid. That is, in the conventional dispensing apparatus, it is not easy to finely adjust the application amount of the light shielding composition liquid by one discharge amount, and the dispensed light shielding composition liquid flows down from the side of the LED chip to form a light shielding film having a desired thickness Is difficult.

Disclosure of the Invention The present invention has been conceived in order to solve the above-mentioned problems, and it is an object of the present invention to provide a light blocking film for an LED chip capable of stably forming a light blocking film by uniformly applying a light blocking composition liquid to a side surface of an LED chip, And a method thereof.

According to an aspect of the present invention, there is provided a method of forming a light shielding film of an LED chip, comprising the steps of: applying a light shielding composition liquid containing a liquid resin and a light shielding composition to a side surface of the LED chip, (A) a reservoir for storing the light-shielding composition liquid; a nozzle formed below the reservoir for allowing the light-shielding composition liquid to be discharged; and a light-shielding layer forming step of And a lower electrode positioned below the pump head to form a potential difference between the upper electrode and the lower electrode; (b) disposing the LED chip on the lower electrode such that an outer periphery of the LED chip faces a nozzle of the pump head; (c) generating a potential difference between the upper electrode and the lower electrode of the pump head so that the side surface of the LED chip can be vertically coated with the light shielding composition liquid so that the light shielding composition liquid stored in the storage portion of the pump head Discharging the first droplet to the side periphery of the LED chip through a nozzle of the pump head; (d) ejecting a second droplet of the light blocking composition liquid onto the first droplet using the pump head; And (e) curing the first droplet and the second droplet of the light blocking composition to be applied to the side surface of the LED chip so as to form the light blocking film on the side surface of the LED chip.

In the method of forming a light blocking film of an LED chip according to the present invention, the light blocking composition is formed into fine droplets by using a potential difference, and is continuously and vertically discharged onto the LED chip, There are advantages to be able to.

1 schematically shows an apparatus used in a method of forming a light blocking film of an LED chip according to an embodiment of the present invention.
2 and 3 are views for explaining a method of forming a light blocking film of an LED chip according to an embodiment of the present invention.

Hereinafter, a method of forming a light blocking film of an LED chip according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic view of a device used in a method of forming a light blocking film of an LED chip according to an embodiment of the present invention. FIGS. 2 and 3 show a method of forming a light blocking film of an LED chip according to an embodiment of the present invention. Fig.

The method of forming a light blocking film of an LED chip according to an embodiment of the present invention is a method of forming a light blocking film on a side surface of an LED chip 10 by continuously spraying a light blocking composition liquid L on the side surface of the LED chip 10 in fine droplets, Of the light shielding film (M). The light-shielding composition liquid (L) is a mixture of a liquid resin and a light-shielding composition. As the light-shielding composition constituting the light-shielding composition liquid (L), various materials capable of blocking or preventing light from being emitted to the outside can be used. As the liquid resin, various kinds of resins that can be cured after being applied to an object such as silicon can be used. The light shielding composition liquid L is cured after a certain time after being applied to the LED chip 10 and is changed into a solid state, that is, a light shielding film M. [

A method of forming a light shielding film of an LED chip according to the present embodiment is a method of forming a light shielding film of a LED chip by using a dispensing pump 20 (hereinafter, referred to as " LED ") having a structure in which a potential difference is generated by a plurality of electrodes 24, 25, (L) by using an EHD (Electro-Hydrodynamic) pump. Such a dispensing apparatus can effectively apply the light shielding composition liquid L to the side surface of the LED chip 10 by using the EHD pump 20.

1 includes an EHD pump 20 for dispensing a light shielding composition liquid L to the LED chip 10, a pump feed mechanism 30 for feeding the EHD pump 20, an LED chip A laser beam irradiator 40 for applying heat to the light shielding composition liquid L applied to the light shielding liquid 10, and a controller 50. The controller 50 controls the operation of the EHD pump 20, the pump feeding mechanism 30, and the laser beam irradiator 40. The components constituting the dispensing apparatus will be briefly described as follows.

The EHD pump 20 includes a pump head 21 and a lower electrode 25. The pump head 21 has a reservoir 22, a nozzle 23 and an upper electrode 24. The storage part 22 is formed in a container shape and stores the light blocking composition liquid L. The light shielding liquid L is stored in a sealed state in the storage part 22 and is continuously supplied through the tube in the storage part 22 by the operation of a separate pneumatic supply device. The nozzle (23) is provided on the lower side of the storage part (22). The light blocking composition liquid (L) is continuously discharged in the form of droplets through the nozzle (23). The upper electrode 24 is disposed so as to be submerged in the light blocking composition liquid L stored in the storage section 22. [ The upper electrode 24 is connected to a power supply 26 and the voltage is regulated by a power supply 26. The upper electrode 24 maintains the potential of the light blocking composition liquid L stored in the storage section 22 to be the same.

The lower electrode 25 is arranged horizontally with respect to the paper surface and is connected to a power supply 26. A chip carrier 15 on which a plurality of LED chips 10 are mounted is disposed on the lower electrode 25. A potential difference is formed between the lower electrode 25 and the upper electrode 24 by the power supply device 26. [ The light shielding liquid L stored in the storage part 22 is discharged as fine droplets from the nozzle 23 by the electric force generated by the potential difference between the lower electrode 25 and the upper electrode 24, And the LED chip 10 on the LED chip 10. That is, a voltage is applied to the upper electrode 24 and the lower electrode 25 by the power supply unit 26 so that the light blocking composition liquid L is discharged as fine droplets from the nozzles 23. The voltage may be applied at a predetermined time interval in the form of a pulse, or may be supplied in such a form that the voltage is raised and lowered in a constant pattern in accordance with the passage of time.

The EHD pump 20 further includes an intermediate electrode 27. The intermediate electrode 27 is disposed between the upper electrode 24 and the lower electrode 25. The intermediate electrode 27 has a through hole 28 through which the light shielding composition liquid L discharged from the nozzle 23 can pass. The intermediate electrode 27 is disposed below the nozzle 23. The intermediate electrode 27 is connected to the power supply unit 26 and serves to form a potential difference between the upper electrode 24 and the lower electrode 25. In some cases, a plurality of intermediate electrodes 27 may be arranged vertically. The voltage of the intermediate electrode 27 is adjusted according to the judgment of the user. The light shielding composition liquid L discharged from the nozzle 23 of the pump head 21 passes through the through hole 28 of the intermediate electrode 27 and falls off the LED chip 10 on the chip carrier 15 thereunder do.

The EHD pump 20 can thinly coat the side surface of the LED chip 10 with the light shielding composition liquid L by successively discharging the light shielding composition liquid L into fine droplets (for example, 0.001 mg).

The laser beam irradiator 40 cures the light shielding composition liquid L applied to the LED chip 10 by applying heat to the fine droplets of the light shielding composition liquid L sprayed on the side surface of the LED chip 10. That is, the laser beam irradiator 40 irradiates a laser beam to increase the curing rate of the light shielding composition liquid L by heating the light shielding composition liquid L applied to the side surface of the LED chip 10. A liquid droplet of the light blocking composition liquid L applied to the side surface of the LED chip 10 by the action of the laser beam irradiator 40 is applied to the side surface of the LED chip 10 and hardened and flows from the side surface of the LED chip 10 A thin film can be formed without falling.

A method of forming a light blocking film of an LED chip according to an embodiment of the present invention using such a dispensing device is as follows.

First, as shown in Fig. 1, the pump head 21, the lower electrode 25 and the intermediate electrode 27 of the EHD pump 20 are arranged at predetermined positions (step (a)). Then, the chip carrier 15 on which the plurality of LED chips 10 are mounted is disposed on the lower electrode 25 (step (b)). At this time, one of the plurality of LED chips 10 mounted on the chip carrier 15 faces the nozzle 23 of the pump head 21 with its outer periphery.

2, a potential difference is generated between the upper electrode 24 and the lower electrode 25 of the pump head 21 so that the light shielding composition liquid (liquid) stored in the reservoir 22 of the pump head 21 L is made into a fine first droplet D1 and discharged toward the outer periphery of the LED chip 10 through the nozzle 23 of the pump head 21 (step (c)). The first droplet D1 of the light shielding composition liquid L discharged from the nozzle 23 passes through the through hole 28 of the intermediate electrode 27 and is vertically applied to the side surface of the LED chip 10. [ The first droplet D1 of the light shielding composition liquid L is coated on the side surface of the LED chip 10 and then the second droplet D2 of the light shielding composition liquid L is supplied to the LED chip 10) (step (d)). The second droplet D2 of the light blocking composition liquid L to be discharged is laminated on the first droplet D1 of the light blocking composition liquid L on the side of the LED chip 10. [ The intermediate electrode 27 is provided so as to smoothly discharge droplets D1 and D2 of the light shielding composition liquid L to the side surface of the LED chip 10, A suitable voltage can be applied to the transistor.

The droplets D1 and D2 of the light shielding liquid L are successively discharged to the side of the LED chip 10 through the nozzle 23 using the potential difference between the upper electrode 24 and the lower electrode 25 A step of curing the droplet D1 (D2) of the light shielding composition liquid L applied to the side surface of the LED chip 10 is performed (step (e)). This curing step can be performed simultaneously with the application of the droplets D1 and D2 of the light shielding composition liquid L to the side surface of the LED chip 10. [ That is, the first droplet D1 of the light blocking composition liquid L is coated on the side surface of the LED chip 10 and cured, and the second droplet D2 of the light blocking composition liquid L is applied to the LED chip 10, And can be cured at the same time. When the droplets D1 and D2 of the light shielding composition liquid L applied to the side surfaces of the LED chip 10 are directly cured, the droplets D1 and D2 of the light shielding composition liquid L adhere to the LED chip 10, It is possible to prevent the light from flowing down from the side surface and to form the light shielding film M having a uniform thickness.

A method of applying heat to the droplets D1 and D2 of the light blocking composition liquid L in order to rapidly cure the droplets D1 and D2 of the light blocking composition liquid L applied to the side surfaces of the LED chip 10 Can be used. In this embodiment, the laser beam irradiator 40 irradiates a laser beam to heat the droplets D1 (D2) of the light shielding composition liquid (L). The droplets D1 and D2 of the light shielding composition liquid L can be hardened simultaneously with application by concentrating the laser beam generated in the laser beam irradiator 40 on the side surface of the LED chip 10. [

The step (c) and the step (d) of applying the droplets D1 and D2 of the light shielding composition liquid L to the side surface of the LED chip 10 with the pump head 21 and the step (Step (e)) of curing the droplets D1 and D2 of the light-shielding composition liquid L applied to the side surfaces of the LED chip 10, It is possible to form a light blocking film M of a thickness. That is, the droplets D1 and D2 of the light shielding composition liquid L are successively discharged perpendicularly to the LED chip 10, vertically stacked from the lower side to the upper side of the side surface of the LED chip 10, The light shielding film M connected to the liquid droplets D1 and D2 of the liquid composition L can be formed. In this process, the pump head 21 is moved along the outer periphery of the LED chip 10 by using the pump feed mechanism 30 to eject droplets D1 and D2 of the light shielding composition liquid L, Can be coated with the light shielding film (M).

As described above, in the method of forming the light blocking film of the LED chip according to the present embodiment, the light shielding composition liquid L is made into fine droplets D1 and D2 by the EHD pump 20, The thickness of the light shielding film M formed on the side surface of the LED chip 10 can be precisely and accurately controlled by continuous ejection.

In other words, unlike the conventional mechanical mechanism pump, the EHD pump 20 can form a fine droplet (for example, 0.001 mg) by coating the light shielding composition liquid L, And can be controlled accurately. Also, since the light blocking film M is formed using the droplets D1 and D2 of the very fine light blocking composition liquid L, the thickness of the light blocking film M can be adjusted much thinner and more accurately than in the prior art. By precisely controlling the thickness of the light shielding film M, the optical characteristics of the LED chip 10 can be uniformly maintained, and a high-quality LED device can be manufactured.

Further, since the application amount of the light-shielding composition liquid (L) can be controlled very accurately, even if a relatively expensive light-shielding composition is mixed with a liquid resin at a high concentration, the loss of the light-shielding composition liquid (L) Can be lowered.

Particularly, in recent years, the LED chip 10 and the LED element have been miniaturized and the area of the region where the light shielding composition liquid L is to be applied is also very small. However, if the present invention is used, It is possible to coat the light-shielding composition liquid (L) in a precise pattern with the capacity, and the quality of the LED element can be improved.

Although the preferred embodiments of the present invention have been described above, the scope of the present invention is not limited to the embodiments described above.

For example, the laser beam irradiator 40 irradiates a laser beam to harden the light shielding composition liquid L applied to the LED chip 10, but the light shielding liquid L may be applied to the LED chip 10, A method of irradiating light other than the laser beam for curing the liquid composition L or applying heat to the light shielding liquid L by another heating device can be used. Alternatively, a method of making a light shielding composition liquid using a photo-curing synthetic resin as a liquid resin of a light blocking composition liquid and curing the light blocking composition liquid applied on the side of the LED chip by irradiating light may be used.

The light blocking composition liquid L is applied to the LED chip 10 while the pump head 21 is moved along the outer periphery of the LED chip 10. However, A method of coating the light shielding composition liquid L on the side surface of the LED chip 10 by moving the lower electrode 25 on which the LED chip 10 is placed may be used.

10: LED chip 15: chip carrier
20: EHD pump 21: pump head
22: storage part 23: nozzle
24: upper electrode 25: lower electrode
26: power supply 27: intermediate electrode
28: through hole 30: pump feeding mechanism
40: laser beam irradiator 50: controller

Claims (8)

1. A method of forming a light blocking film for an LED chip for forming a light blocking film on a side surface of an LED chip by applying a light blocking composition containing a liquid resin and a light blocking composition on a side surface of the LED chip,
(a) a reservoir for storing the light-shielding composition liquid; a nozzle formed below the reservoir for allowing the light-shielding composition liquid to be discharged; and a nozzle disposed below the reservoir to adjust the potential of the light- Disposing a lower electrode positioned below the pump head so as to form a potential difference between the upper electrode and the pump head;
(b) disposing the LED chip on the lower electrode such that an outer periphery of the LED chip faces a nozzle of the pump head;
(c) generating a potential difference between the upper electrode and the lower electrode of the pump head so that the side surface of the LED chip can be vertically coated with the light shielding composition liquid so that the light shielding composition liquid stored in the storage portion of the pump head Discharging the first droplet to the side periphery of the LED chip through a nozzle of the pump head;
(d) ejecting a second droplet of the light blocking composition liquid onto the first droplet using the pump head; And
(e) curing the first droplet and the second droplet of the light blocking composition to be applied to the side surface of the LED chip so as to form the light blocking film on the side surface of the LED chip A method for forming a light blocking film. The method according to claim 1,
Wherein the step (e) comprises curing the first droplet and the second droplet of the light shielding composition applied on the side of the LED chip by applying heat thereto. 3. The method of claim 2,
Wherein the step (e) comprises heating the first droplet and the second droplet of the light shielding composition applied to the side surface of the LED chip by irradiating a laser beam. The method according to claim 1,
Wherein the liquid resin of the light shielding composition liquid is a photo-curable synthetic resin, and the step (e) comprises irradiating light to the first droplet and the second droplet of the light shielding composition applied to the side of the LED chip, A method of forming a light blocking film of an LED chip. The method according to claim 1,
Wherein the step (c) and the step (d) are performed while moving the pump head along the outer periphery of the LED chip. The method according to claim 1,
(C) to (e) are repeated so as to coat the entire side surface of the LED chip with droplets of the light shielding composition liquid. The method according to claim 1,
The step (e) is characterized in that a first droplet of the light blocking composition liquid is coated on the side surface of the LED chip and simultaneously cured, and the second droplet of the light blocking composition liquid is coated on the side surface of the LED chip, Wherein the light-blocking film is formed on the LED chip. The method according to claim 1,
Wherein the step (a) includes the steps of: forming a first droplet of the light blocking composition liquid and a through hole through which the second droplet can pass, and forming an intermediate electrode, which forms a potential difference between the upper electrode and the lower electrode, And the lower electrode is disposed between the upper electrode and the lower electrode.
KR1020150071554A 2015-05-22 2015-05-22 Method for Forming Light Blocking Layer of LED Chip KR20160137815A (en)

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KR1020150071554A KR20160137815A (en) 2015-05-22 2015-05-22 Method for Forming Light Blocking Layer of LED Chip

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