KR20110108002A - Light emitting diode device and manufacturing method thereof - Google Patents

Abstract

The present invention relates to a light emitting diode device and a manufacturing method thereof, comprising: an LED chip formed on a wafer and provided with a bonding pad on an upper surface thereof; And a phosphor formed to expose the bonding pad on the LED chip. The present invention also provides a method of manufacturing the light emitting diode device.

Description

Light emitting diode device and method of manufacturing the same

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light emitting diode device and a method of manufacturing the same, and more particularly, to a light emitting diode device and a method of manufacturing the same in which a phosphor is applied only to a desired area at a wafer level on an LED chip.

In general, a light emitting diode (hereinafter, referred to as an LED) constitutes a light emitting source by changing a compound semiconductor material such as GaAs, AlGaAs, GaN, InGaN, and AlGaInP, thereby realizing various colors of light. Refers to a semiconductor device.

Recently, thanks to the rapid development of semiconductor technology, LED devices have escaped from general-purpose products with low brightness, and have been able to produce high-brightness and high-quality products, and their application value has been expanded to displays and next-generation lighting sources.

As a method of implementing white color with such LEDs, a method using a phosphor and a method of simply combining blue, green, and red LEDs are known.

Among them, a method of manufacturing a white LED device using a phosphor includes a method of applying a yellow phosphor on a blue LED chip and a process of applying red and green phosphor on a blue LED chip together. Methods and the like are widely used.

However, at present, the method of applying the phosphor to the LED chip has a disadvantage in mass production as a method of applying to the individual packaged LED. Therefore, there is a need in the art for new ways to enable mass production.

Accordingly, the present invention has been made to solve the above problems, and an object of the present invention is to apply a phosphor to a desired area at a wafer level by using a mask blocking a bonding pad on a plurality of LED chips formed on a wafer. In addition, the present invention provides a light emitting diode device capable of mass production and eliminating unnecessary use of a phosphor, and a method of manufacturing the same.

A light emitting diode device according to an embodiment of the present invention for achieving the above object, the LED chip formed on the wafer and provided with a bonding pad on the upper surface; And a phosphor formed to expose the bonding pad on the LED chip.

Here, the phosphor may be dispersed in a transparent resin layer formed to expose the bonding pads on the LED chip.

In addition, the phosphor may include at least one of yellow, red, green, and blue phosphors.

In addition, a method of manufacturing a light emitting diode device according to an embodiment of the present invention for achieving the above object comprises the steps of: forming a plurality of LED chips with bonding pads on a wafer; Disposing a mask on the LED chip to block the bonding pad and to expose a surface of the LED chip; And applying a phosphor to a surface of the LED chip exposed to the mask.

Here, in the step of applying the phosphor, the phosphor may be applied by a spray method.

The method may further include forming a transparent resin layer on a surface of the LED chip exposed to the mask before applying the phosphor.

Further, in the step of applying the phosphor, at least one of yellow, red, green and blue phosphor may be applied.

In addition, when at least two or more of the yellow, red, green, and blue phosphors are selected and applied, the selected phosphors may be mixed with each other, or sequentially applied.

As described above, according to the light emitting diode device and the manufacturing method thereof according to the present invention, it is possible to mass-produce by applying a phosphor to a desired area at the wafer level using a mask on a plurality of LED chips formed on the wafer. There is this.

In addition, the present invention can selectively apply the phosphor only to the desired area, that is, the surface of the LED chip excluding the bonding pad, using a mask to block the bonding pad, there is an effect that can reduce the amount of unnecessary phosphor.

Therefore, the present invention has the advantage of lowering the manufacturing cost of the light emitting diode device by reducing the material cost of the phosphor.

1 is a cross-sectional view showing the structure of a light emitting diode device according to an embodiment of the present invention.
2 to 6 are cross-sectional views sequentially showing a method of manufacturing a light emitting diode device according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings of a light emitting diode device and a method of manufacturing the same. The following embodiments are provided as examples to sufficiently convey the spirit of the present invention to those skilled in the art. Accordingly, the invention is not limited to the embodiments described below and may be embodied in other forms. In the drawings, the size and thickness of the device may be exaggerated for convenience. Like reference numerals designate like elements throughout the specification.

A light emitting diode device according to an exemplary embodiment of the present invention will be described in detail with reference to FIG. 1.

1 is a cross-sectional view showing the structure of a light emitting diode device according to an embodiment of the present invention.

As shown in FIG. 1, a light emitting diode device according to an exemplary embodiment of the present invention includes a wafer 100, an LED chip 110 formed on the wafer 100, and a phosphor formed on the LED chip 110. 140.

The LED chip 110 is a light emitting source for generating light of various colors such as blue light, red light, green light or ultraviolet light, and may be a gallium nitride-based LED chip.

A bonding pad 120 is provided on an upper surface of the LED chip 110.

Here, in the exemplary embodiment of the present invention, the LED chip 110 is a horizontal LED chip. In this case, the bonding pad 120 includes two bonding pads, that is, the first bonding pad 121 and the second bonding. It may include a pad 122.

That is, in the LED chip 110, after the n-type nitride semiconductor layer, the active layer, and the p-type nitride semiconductor layer are sequentially stacked, the p-type nitride semiconductor layer and the active layer are partially mesa-etched to form a portion of the upper surface of the n-type nitride semiconductor layer. The first bonding pad 121 is provided on the p-type nitride semiconductor layer, the second bonding pad 122 is provided on the n-type nitride semiconductor layer. It may be.

The number and location of the bonding pads 120 may be changed according to the structure of the LED chip 110.

In the LED device according to the embodiment of the present invention, the phosphor 140 is formed to expose the bonding pad 120 on the LED chip 110.

The phosphor 140 includes a mask (see reference numeral “200” in FIG. 3) that blocks the bonding pad 120 and exposes an upper surface of the LED chip 110 on the LED chip 110. In this state, the surface of the LED chip 110 exposed to the mask 200 may be selectively applied by a spray method or the like.

The phosphor 140 may include at least one of yellow, red, green, and blue phosphors, which are generated in the LED chip 110. White light can be emitted by combining with the light.

In this case, the phosphor 140 may be dispersed in the transparent resin layer 130 formed to expose the bonding pad 120 on the LED chip 110.

The transparent resin layer 130 may be made of a silicone resin, an epoxy resin, or the like, and may prevent deterioration of the phosphor 140.

A method of manufacturing a light emitting diode device according to an embodiment of the present invention will be described in detail with reference to FIGS. 2 to 6.

2 to 6 are cross-sectional views sequentially illustrating a method of manufacturing a light emitting diode device according to an exemplary embodiment of the present invention.

First, as shown in FIG. 2, a plurality of LED chips 110 are formed on the wafer 100. The plurality of LED chips 110 may be formed to be spaced apart from each other at a predetermined interval.

A bonding pad 120 is provided on an upper surface of the LED chip 110.

Here, in the embodiment of the present invention, as described above, the LED chip 110 is a horizontal type LED chip, and in this case, the bonding pad 120 includes two bonding pads, that is, the first bonding pad 121. And a second bonding pad 122. The first bonding pads 121 may be formed on the p-type nitride semiconductor layer, and the second bonding pads 122 may be formed on the n-type nitride semiconductor layer.

The LED chip 110 may be a chip that emits various colors such as blue, red, or green. The light generated by the LED chip 110 may emit white light through a combination with the phosphor 140 to be described later.

Next, as shown in FIG. 3, a mask 200 is disposed on the LED chip 110 to block the bonding pad 120 and expose the surface of the LED chip 110. In this case, the mask 200 may cover the wafer 100 exposed between the LED chips 110 spaced apart from each other along with the bonding pads 120.

That is, the mask 200 may include an opening that exposes the surface of the LED chip 110 as shown in the figure.

The mask 200 may be made of glass or a metal material.

Next, as shown in FIG. 4, the phosphor 140 is coated on the surface of the LED chip 110 exposed to the mask 200. The phosphor 140 may be applied by a spray method or the like.

That is, a spray is disposed at a position corresponding to the LED chip 110 on the mask 200 that selectively exposes only the surface of the LED chip 110, and the phosphor 140 is sprayed through the spray to emit the LED chip. The phosphor 140 may be applied only to the surface of the 110.

According to the embodiment of the present invention, by applying the phosphor 140 by the spray method, there is an advantage that the uniformity of the color may be improved by making the thickness of the phosphor 140 applied uniformly.

In addition, according to the manufacturing method of the light emitting diode device according to the embodiment of the present invention, since the bonding pad 120 is covered by the mask 200, the phosphor 140 may exclude the bonding pad 120. It may be selectively applied only to the surface of the LED chip 110.

Therefore, according to an embodiment of the present invention, mass production is achieved by applying the phosphor 140 only on a desired area at the wafer level using the mask 200 on the plurality of LED chips 110 formed on the wafer 100. There are possible advantages.

In addition, in the embodiment of the present invention, by using the mask 200 covering the bonding pad 120 as described above, the phosphor is selectively only on the surface of the LED chip 110 excluding the desired area, that is, the bonding pad 120. Since 140 can be applied, the amount of unnecessary phosphor 140 can be reduced.

Therefore, the present invention has the advantage of lowering the manufacturing cost of the light emitting diode device by reducing the material cost of the phosphor 140.

Here, before applying the phosphor 140, the transparent resin layer 130 may be formed on the surface of the LED chip 110 exposed to the mask 200. Silicone resin or epoxy resin may be used as the transparent resin layer 130.

When the transparent resin layer 130 is formed as described above and then the phosphor 140 is coated, the phosphor 140 may be dispersed in the transparent resin layer 130 to prevent deterioration of the phosphor 140. There is an advantage.

When the phosphor 140 is applied, at least one of yellow, red, green, and blue phosphors may be applied.

In this case, when at least two or more of the yellow, red, green, and blue phosphors are selected and applied, the selected phosphors may be mixed and applied, or the selected phosphors may be sequentially applied.

That is, in order to obtain white light, when the blue LED chip is used as the LED chip 110, the yellow phosphor may be coated on the blue LED chip alone, or the red and green phosphors may be applied together. Here, when the red and green phosphors are applied together on the blue LED chip, the red and green phosphors may be mixed and applied to each other, or the red and green phosphors may be sequentially applied.

In addition, when the ultraviolet LED chip is used as the LED chip 110, white light may be obtained by coating blue, green, and red phosphors on the ultraviolet LED chip. In this case, the blue, green and red phosphors may be mixed and applied to each other, or they may be sequentially applied.

Thereafter, as shown in FIG. 5, when the application of the phosphor 140 is completed, the mask 200 is removed.

Then, as illustrated in FIG. 6, the wafer 100 is cut and divided into chip units.

According to the embodiment of the present invention as described above, when the coating of the phosphor 140 on the LED chip 110 is completed, the bonding pad 120 of the LED chip 110 by the phosphor 140 Since it is exposed, the wire bonding operation needs to be performed only once on the exposed bonding pad 120 during the subsequent packaging.

And, according to the embodiment of the present invention, since the phosphor 140 is not formed on the upper surface of the bonding pad 120 to which the metal wire is bonded, the contact between the metal wire and the phosphor 140 There is an advantage in that the reliability of the light emitting device can be improved by preventing wire open defects.

Preferred embodiments of the present invention described above are disclosed for the purpose of illustration, and various substitutions, modifications, and changes within the scope without departing from the spirit of the present invention for those skilled in the art to which the present invention pertains. It will be possible, but such substitutions, changes and the like should be regarded as belonging to the following claims.

100: wafer
110: LED chip
121: first bonding pad
122: second bonding pad
120: bonding pad
130: transparent resin layer
140: phosphor
200: mask

Claims (8)

An LED chip formed on the wafer and provided with a bonding pad on an upper surface thereof; And
A phosphor formed to expose the bonding pads on the LED chip;
Light emitting diode device comprising a.
The method of claim 1,
The phosphor is dispersed in a transparent resin layer formed to expose the bonding pad on the LED chip.
The method of claim 1,
The phosphor includes at least one of yellow, red, green and blue phosphors.
Forming a plurality of LED chips with bonding pads on the wafer;
Disposing a mask on the LED chip to block the bonding pad and to expose a surface of the LED chip; And
Applying a phosphor to a surface of the LED chip exposed to the mask;
Method for manufacturing a light emitting diode device comprising a.
The method of claim 4, wherein
In the step of applying the phosphor,
The method of manufacturing a light emitting diode device, characterized in that for applying the phosphor in a spray method.
The method of claim 4, wherein
Before applying the phosphor,
Forming a transparent resin layer on a surface of the LED chip exposed to the mask;
Method of manufacturing a light emitting diode device characterized in that it further comprises.
The method of claim 4, wherein
In the step of applying the phosphor,
A method of manufacturing a light emitting diode device, wherein at least one of yellow, red, green, and blue phosphors is applied.
The method of claim 7, wherein
When at least two or more of the yellow, red, green, and blue phosphors are selected and applied, the selected phosphors are mixed with each other, or sequentially applied.

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