KR101915408B1 - Apparatus and method for coating phosphor on led chips - Google Patents

Abstract

The present invention relates to an apparatus for coating a phosphor of an LED chip which uniformly forms the thickness and the height of a phosphor liquid resin coated on a respective LED chip, and furthermore uniformly forms the thickness and the height of a phosphor liquid resin coated on an LED chip set so as to accurately represent target color characteristics and to improve the optical quality. The apparatus comprises: a coating head for discharging a phosphor liquid resin; and a blade fixed in a direction in which the LED chip coated in the coating head is discharged, and adjusting the thickness of the phosphor liquid resin on an LED chip as a lower tip unit is positioned lower than a die slot of a lower part of the coating head.

Description

FIELD OF THE INVENTION [0001] The present invention relates to an LED chip,

The present invention relates to an apparatus and a method for coating a phosphor on an LED chip, and more particularly, to a method and apparatus for coating a phosphor on a LED chip by uniformly controlling the thickness and height of the phosphor liquid resin coated on the LED chip, And more particularly, to a phosphor coating apparatus and method of an LED chip in which target color characteristics are accurately expressed and optical quality is improved.

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

The color coordinate value of the LED element can be adjusted by adjusting the amount of the fluorescent liquid resin to be discharged 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 phosphor liquid resin, it is necessary to precisely control the amount of the phosphor liquid resin in a very small unit. Recently, miniaturization of LED chips has been demanded, and a technique capable of applying a small amount of fluorescent liquid resin to a LED chip in a predetermined amount is required.

In addition to the problem of adjusting the amount of the phosphor liquid resin in the individual LED chip, the size of the individual LED chip is very small. Therefore, the shape of the phosphor liquid resin applied to the LED chip affects the target color characteristic and the optical quality of the final LED chip I'm crazy. The coating type of the phosphor liquid resin should have a constant thickness and height according to the desired color characteristics. It is difficult to keep the coated surface constant due to the surface tension due to the viscosity of the phosphor liquid resin itself and the fine adjustment of the liquid resin resin discharge amount It has been difficult to coat the phosphor with a desired thickness and height.

Korean Patent Publication No. 2013-0081029

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above problems, and it is an object of the present invention to provide a phosphor liquid resin coated on an LED chip with uniform thickness and height, To thereby provide a phosphor coating apparatus and method of an LED chip in which target color characteristics are accurately expressed and optical quality is improved.

Another object of the present invention is to provide a LED chip capable of satisfying a target color characteristic while minimizing a yield deterioration since a void generated on a side surface of the LED chip can be prevented only by a simple process change during the coating process of the phosphor liquid resin And to provide a phosphor coating apparatus and method.

In order to solve the above-mentioned problems, the present invention provides a coating apparatus comprising: a coating head for discharging a phosphor liquid resin; And a blade fixed at a direction in which the coated LED chip is discharged from the coating head and whose lower tip portion is positioned below the die slot below the coating head to adjust the thickness of the fluorescent liquid resin on the LED chip; The phosphor coating apparatus of the LED chip according to the present invention comprises:

Preferably, the horizontal sensor measures the horizontal inclination of the coating head itself; And a horizontal control driver for adjusting the horizontal inclination of the coating head; And further comprising:

Preferably, the displacement sensor measures the height of the phosphor liquid resin applied to the LED chip; And a head lifting driver for lifting the coating head and the blade; And further comprising:

Preferably, the displacement sensor measures the distance between the coating head and the coating upper surface of the LED chip underlying the coating head, and the controller measures the current tilt between the coating head and the coating upper surface through the distance measurement, The inclination of the coating head and the blade is corrected through the LED chip, and the distance between the LED chip and the upper surface of the coating is measured with respect to a plurality of LED chip positions in the same row.

Preferably, the displacement sensor measures the distance between the coating head and the upper surface of the coating of the LED chip located below the coating head, and the controller measures the height of the coating upper surface through the distance measurement value, And the height of the blade, and the distance measurement of the LED chip with the upper surface of the coating is performed for a plurality of LED chip positions in the same row.

Preferably, the die slot of the coating head is arranged to be twisted by 5 to 45 degrees in a direction perpendicular to the direction in which the LED chip moves.

According to another aspect of the present invention, there is provided a method of manufacturing an LED chip, comprising the steps of: (a) aligning a table for transporting a set of LED chips under a coating head in an empty state; (b) lowering the coating head through the head elevation driver to bring the die slot of the coating head into close contact with the upper surface of the table; (c) operating a horizontal sensor to measure a horizontal slope of the current coating head and to set a current horizontal slope state of the measured coating head to a zero value; (d) operating a displacement sensor to measure a distance between the coating head and the table, and setting a distance to the measured table to a zero value; (e) raising the coating head, discharging the phosphor liquid resin to the lower LED chip, and simultaneously processing the thickness and height of the phosphor liquid resin applied to the LED chip through the blade; (f) measuring the distance between the coating head and the upper surface of the coating with respect to the position of the plurality of LED chips in the same row under the coating head with the displacement sensor; (g) calculating the measured distance values to measure a current tilt between the coating head and the coating upper surface, and driving the horizontal control actuator according to the difference of the zero values to correct horizontal tilt of the coating head and the blade; And (h) calculating the measured distance values to measure the phosphor coating thickness and driving the head elevation driver according to the target color coordinate value to correct the height of the coating head and the blade; The present invention also provides a method for coating a phosphor of an LED chip.

Preferably, in the step (e), the die slot of the coating head is arranged to be twisted by 5 to 45 degrees in a direction perpendicular to the direction in which the LED chip moves.

According to the present invention, the thickness and height of the phosphor liquid resin coated on the individual LED chips are made constant, and the thickness and height of the phosphor liquid resin coated on the LED chip set are made constant, The quality is improved.

In addition, the voids generated on the side surface of the LED chip during the coating process of the liquid resin can be prevented by only a simple process change, so that the target color characteristic can be satisfied while minimizing the yield deterioration.

1 and 2 are views for explaining a phosphor coating process and a result of a conventional technique.
3 is a view showing a phosphor coating apparatus of an LED chip according to an embodiment of the present invention.
4 is a view for explaining phosphor coating results of a phosphor coating apparatus of an LED chip according to an embodiment of the present invention.
5 is a view for explaining the direction and results of phosphor coating according to the prior art.
6 is a view for explaining a phosphor coating direction and results according to an embodiment of the present invention.
7 is a view for explaining a method of coating a phosphor of an LED chip according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 and 2 are views for explaining a phosphor coating process and a result of a conventional technique.

When the phosphor liquid resin (P) is ejected to each LED chip in the manufacture of an LED device, a coating upper surface having an uneven coating thickness is formed as shown in FIG. 1, Which hinders the development of color characteristics. Conventionally, as shown in FIG. 1, the upper surface of the coated phosphor liquid resin is grinded with a separate grinder G so that the upper surface of the coating of the phosphor liquid resin P has a certain thickness. However, such a separate grinding operation eventually increases the production time and increases the production cost.

In addition, when the phosphor liquid resin P having a predetermined viscosity is discharged through the coating head, the phosphor liquid resin P is discharged from the coating head due to the horizontal manifold shape in which the phosphor liquid resin P is diffused in the coating head. (Y-axis) portion of the time is different. As shown in FIG. 2, due to the difference in the discharge time between horizontal portions of the coating head and the surface tension due to the viscosity of the phosphor liquid resin (P) itself, a convex shaped acid is formed at both ends, P) on the upper surface is uneven, thereby hindering the expression of the target LED color characteristic. Unlike the past, LED chips have been produced by neglecting such coating acids. Unlike in the past, however, it is a clear need for improvement in current market conditions that require precise color characteristics for each LED chip. In addition, there is a separate grinding work to improve this, but this also increases the production time and increases the production cost.

3 is a view showing a phosphor coating apparatus of an LED chip according to an embodiment of the present invention.

3, the phosphor coating apparatus of the LED chip comprises a coating head 10 for discharging a phosphor liquid resin P and a horizontal sensor 20 for measuring the horizontal inclination (Y axis) of the coating head 10 itself A horizontal control actuator 30 for controlling the horizontal inclination of the coating head 10 to level the coating posture of the coating head 10, a head elevation driver 40 for raising and lowering the coating head 10, A displacement sensor 50 for measuring the height of the phosphor liquid resin P applied to the chip 60 and the LED chip 62 controlling the respective structures to control the application of the phosphor liquid resin P to a predetermined thickness And a control unit 70 as shown in FIG.

The LED chips 62 to be manufactured here will be transported horizontally while being fixed to the chip carrier 61 on the table 60 and moved below the phosphor liquid resin P discharge position of the coating head 10. [

A plurality of LED chips 62 are arranged in the longitudinal direction of the chip carrier 61 in the coating process. The LED chips 62 are composed of LED chip sets. The LED chips 62 have a die slot 11 formed in a Y- A plurality of LED chips 62 in the same row will be sequentially coated while passing the LED chip 10 in the X-axis direction.

The coating head 10 receives the phosphor liquid resin mixed with the phosphor and the transparent liquid resin from the phosphor liquid resin reservoir (not shown) at a predetermined mixing ratio, discharges the phosphor liquid resin through the slot die 11 formed at the lower side, The phosphor coating operation is performed by applying the coating liquid to the chip 62. In the figure, reference numeral 13 denotes a supply pipe for the coating head 10 to receive the phosphor liquid resin from the phosphor liquid resin reservoir.

The coating head 10 transports the supplied phosphor liquid resin P to the inner center along the inner channel and discharges the phosphor liquid P to the manifold formed inside the coating head 10 through the supply port at the end of the channel, The resin P is diffused inside and then discharged in a row (Y-axis direction) through the die slot 11 at the lower end.

The LED chip set in the lower portion of the coating head 10 is coated with the phosphor liquid resin all at once in accordance with the movement of the chip carrier 61 in the longitudinal direction (X-axis direction).

The coating head 10 is provided with a head elevating driver 40 for moving the coating head 10 up and down under the control of the controller 70. The head elevating driver 40 lowers the coating head 10 during the coating operation and raises the coating head 10 in the standby state. Further, the head lifting driver 40 can precisely raise and lower the coating head 10 in the vertical direction for precise control of the coating thickness.

Here, the blade 17 is fixed to the side of the coating head 10 on which the LED chip 62 is coated. That is, the blade 17 is fixedly installed in a direction in which the coated LED chip is discharged out of the side surfaces of the coating head 10. The blade 17 is fixed to the coating head 10 and moves up and down together with the up and down driving of the lifting and lowering driver 40 with respect to the coating head 10. The lower tip of the blade 17 scrapes the upper surface of the phosphor liquid resin P applied to the LED chip 62 to adjust the thickness and height of the phosphor liquid resin P coated on the LED chip 62 to a constant .

Referring to FIG. 4 (a), the upper surface of the phosphor liquid resin P applied to the LED chip 62 by the coating head 10 has an uneven coating thickness. The blade 17 is provided on the side of the coating head 10 to scrape the upper surface of the phosphor liquid resin P immediately before the phosphor liquid resin P applied to the LED chip 62 is cured The upper surface of the phosphor liquid resin P coated on the LED chip 62 is leveled as shown in Fig. 4 (b).

Therefore, in order to adjust the color coordinate value of the LED element, the phosphor liquid resin P is discharged with a preset discharge amount in the LED package and the target color coordinate value is adjusted. However, the height of the blade 17 So that the entire LED chips 62 in the working process can be adjusted to have the same color characteristics and the same optical quality.

The lower end of the blade 17 is extended horizontally in the same manner as the die slot 11 at the tip of the coating head 10 so that all of the LED chips 62 coated by the coating head 10, So that the upper surface of the wafer W is processed at a time.

Here, the lower end of the blade 17 may be located below the die slot 11 under the coating head 10.

The horizontal sensors 20 are disposed on the left and right sides of the coating head 10 to measure a left-right inclination (Y-axis direction) of the coating head 10. If the inclination of the coating head 10 is not in a horizontal state, a slope is formed in the process of processing the upper surface of the blade 17 with respect to a plurality of LED chips arranged in the LED chip set, Keeping up is very important.

The horizontal control driver 30 is disposed on each of the left and right sides of the coating head 10 to pull the coating head 10 from the left and right to adjust the tilt. Here, the reference numeral 31 denotes a hinge that allows the body to be smoothly rotated for adjusting the tilt in accordance with the driving of the horizontal control drivers 30 on the left and right sides.

The displacement sensor 50 measures the distance between the coating head 10 and the upper surface of the coating of the LED chip 62 located therebelow. Such a distance measurement of the LED chip 62 to the upper surface of the coating is performed for a plurality of LED chip positions in the same row.

When the displacement sensor 50 measures the distance value relative to the upper surface of the coating for a plurality of chip positions in the same row, the current tilt (Y axis) between the coating head and the upper surface of the coating can be measured. The current tilt measurement between the coating head coating head and the coating top surface will enable the tilt change of the coating head during operation to be sensed.

Also, if the displacement sensor 50 measures the distance value with respect to the upper surface of the coating for a plurality of chip positions in the same row, the height of the upper surface of the coating (thickness of the coating surface) can be measured. The height of the coating head and the height of the blade are adjusted according to the measurement result of the height of the upper surface of the coating (thickness of the coating surface), so that the target color coordinate value can be corrected.

On the other hand, the LED chips 62 are arranged longitudinally and laterally to the chip carrier 61 in the coating process of the phosphor liquid resin, and have a die slot 11 formed in a Y axis direction as shown in FIG. 6 (a) The coating of the LED chips 62 in the same row is sequentially performed while the coating head 10 is moved in the X axis direction.

6 (b), the phosphor liquid resin is coated on the side of the side surface of the LED chip 62 facing the coating head during the application of the phosphor liquid resin, A void (V) is formed which can not escape from the air in a short time.

The voids V scatter light in an unwanted direction as air bubbles, thereby causing the LED chip 62 to exhibit color characteristics different from the target color characteristics to be obtained through the application of the fluorescent liquid resin of the LED chip 62, It is becoming a cause.

The present invention proposes a method for eliminating voids (V) on the side of the LED chip 62 in consideration of such a problem as follows.

7, the coating head 10 is twisted at a certain angle without arranging the coating head 10 in the Y axis direction perpendicular to the X axis direction with respect to the chip carrier 61 passing the coating head 10 in the X axis direction, It is possible to arrange it.

That is, as shown in FIG. 7A, the coating head 10 can be twisted by about 25 degrees in the Y-axis direction.

In this case, the phosphor liquid resin is not applied to the entire side surface at the side of the LED chip 62 which is moved at the same time, and the LED chip 62 reaches the long die slot 11 of the coating head 10 first The application to the side surface of the LED chip 62 will be sequentially performed.

Accordingly, the air present on the side surface of the LED chip 62 is naturally pushed in the diagonal direction by the phosphor liquid resin in accordance with the sequential application, and as shown in FIG. 7 (b) The voids V are not formed.

In the above description and drawings, an example is described in which the coating head 10 is twisted about 25 degrees in the Y-axis direction with respect to the chip carrier 61 passing in the X-axis direction. In accordance with this principle, It can be achieved by disposing the coating head 10 by twisting about 5 to 45 degrees in the Y-axis direction.

In the above description and drawings, an example in which the coating head 10 is slightly twisted in the Y-axis direction has been described. However, even if the moving direction of the chip carrier 61 is bit-wise to some extent in the X- The effect can be achieved.

The phosphor coating apparatus of the LED chip described above is operated in a vacuum chamber, and the chip carrier 61 and the LED chips 62 disposed thereon enter the corresponding chamber to perform a coating operation, In-void will be removed.

Referring now to FIG. 7, a method of coating a phosphor of an LED chip according to an embodiment of the present invention will be described.

First, in step S10, a table 60 for transporting a set of LED chips under the coating head 10 is emptied to make a state in which nothing is placed on the table 60.

Of course, the upper surface of the table 60 may be a horizontal surface.

Thereafter, in step S11, the head elevating driver 40 is driven through the controller 70 to lower the coating head 10, and the die slot 11 of the coating head 10 is brought into close contact with the upper surface of the table 60 .

The coating head 10 will be perfectly horizontal with the upper surface of the table 60 and the die slot 11 of the coating head 10 will not be spaced apart from the upper surface.

Thereafter, in step S12, the controller 70 operates the horizontal sensor 20 to measure the horizontal inclination of the current coating head 10 and set the current horizontal inclination state of the measured coating head 10 to a zero value.

In step S13, the controller 70 operates the displacement sensor 50 to measure the distance between the coating head 10 and the table 60 and set the distance to the measured table 60 to zero .

Thereafter, in step S14, the LED chip set is aligned on the chip carrier 61 on the table 60 after the coating head 10 is raised to prepare the coating process.

Thereafter, in step S15, the phosphor liquid resin P is discharged through the slot die 11 formed on the lower side of the coating head 10 and applied to the lower LED chip 62, and at the same time, The upper surface of the phosphor liquid resin P applied to the chip 62 is scratched and the thickness and height of the phosphor liquid resin P coated on the LED chip 62 are processed.

Here, in order to prevent voids (V) in the coating with respect to the LED chip 62, the coating head 10 or the chip carrier 61 is twisted about ± 5 to 45 degrees in the Y axis direction It is preferable that the phosphor liquid resin (P) is applied.

Thereafter, in step S16, the controller 70 measures the distance between the coating head 10 and the coating upper surface of the LED chip 62 located below the coating head 10 with the displacement sensor 50. Such a distance measurement of the LED chip 62 to the upper surface of the coating is performed for a plurality of LED chip positions in the same row.

Thereafter, in step S17, the controller 70 calculates distance values between the coating head and the upper surface of the coating at a plurality of positions in the same column to measure the current tilt (Y axis) between the coating head and the coating upper surface. If the slope is different from the zero value set in step S12, it is determined that a slant that is shifted has occurred and the horizontal control driver 30 is driven to correct the horizontal slope of the coating head 10. [ Such a horizontal tilt correction of the coating head 10 will be equally applied to the blades 17 interlocked with the corresponding coating head 10.

Thereafter, in step S18, the controller 70 calculates distance values of the coated upper surface at a plurality of positions in the same column to measure the phosphor coating thickness. Of course, the thickness of the chip carrier 61 added after the zero setting for such a coating thickness measurement will be removed as a deviation. By measuring the thickness of the phosphor coating, the height of the coating head 10 is corrected so that a target color coordinate value can be displayed. Such height correction of the coating head 10 will be equally applied to the blades 17 interlocked with the corresponding coating head 10. By adjusting the thickness of the coating through the height correction of the blade 17, Can be changed.

As described above, an optimal embodiment has been disclosed in the drawings and specification. Although specific terms have been employed herein, they are used for purposes of illustration only and are not intended to limit the scope of the invention as defined in the claims or the claims. It will be understood by those skilled in the art that various modifications and equivalents may be made thereto without departing from the scope of the present invention. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

10: coating head 11: die slot
13: supply pipe 17: blade
20: Horizontal sensor 30: Horizontal control actuator
40: head lift actuator 50: displacement sensor
60: Table 61: Chip carrier
62: LED chip 70:

Claims (8)

delete delete delete delete delete delete (a) aligning a table for transporting a set of LED chips below the coating head in an empty state;
(b) lowering the coating head through the head elevation driver to bring the die slot of the coating head into close contact with the upper surface of the table;
(c) operating a horizontal sensor to measure a horizontal slope of the current coating head and to set a current horizontal slope state of the measured coating head to a zero value;
(d) operating a displacement sensor to measure a distance between the coating head and the table, and setting a distance to the measured table to a zero value;
(e) raising the coating head, discharging the phosphor liquid resin to the lower LED chip, and simultaneously processing the thickness and height of the phosphor liquid resin applied to the LED chip through the blade;
(f) measuring the distance between the coating head and the upper surface of the coating with respect to the position of the plurality of LED chips in the same row under the coating head with the displacement sensor;
(g) calculating the measured distance values to measure a current tilt between the coating head and the coating upper surface, and driving the horizontal control actuator according to the difference of the zero values to correct horizontal tilt of the coating head and the blade; And
(h) calculating the measured distance values to measure the phosphor coating thickness and driving the head elevation driver according to the target color coordinate value to correct the height of the coating head and the blade; The method of claim 1,
8. The method of claim 7,
In the step (e)
Wherein the die slot of the coating head is arranged to be twisted by 5 to 45 degrees in a direction perpendicular to the direction in which the LED chip moves.

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