KR100881175B1 - Light emitting diode having unevenness and method for manufacturing the same - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light emitting diode having irregularities and a method of manufacturing the same. And a step of scribing, wherein the scribing comprises scribing the substrate in a direction different from the crystal lattice direction of the substrate. .

Light Emitting Diode, Unevenness, Side, Scribing, Crystal Grid Direction

Description

Light-emitting diodes with irregularities and manufacturing method thereof {Light emitting diode having unevenness and method for manufacturing the same}

1 is a cross-sectional view of a light emitting diode according to the prior art.

2 is a plan view of a light emitting diode according to an exemplary embodiment of the present invention, and FIG. 3 is a cross-sectional view of the light emitting diode shown in FIG. 2 taken along the line I-I.

4 is a schematic cross-sectional view of a vertical light emitting diode according to another embodiment of the present invention.

5 to 8 illustrate a method of manufacturing a light emitting diode according to an embodiment of the present invention.

* Description of the symbols for the main parts of the drawings *

110: substrate

120: n-type semiconductor layer

130: active layer

140: p-type semiconductor layer

150: p electrode

155: bonding pads

160: n electrode

170: unevenness

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light emitting diode having irregularities formed therein and a method of manufacturing the same.

1 is a cross-sectional view of a light emitting diode according to the prior art. Referring to FIG. 1, the light emitting diode includes a buffer layer 20, an n-type semiconductor layer 30, an active layer 40, and a p-type semiconductor layer 50 that are sequentially stacked on the substrate 10, and The p electrode 60 is formed on the p-type semiconductor layer 50 and the n-electrode 70 formed on the n-type semiconductor layer 30 exposed by a predetermined region through etching. When the light emitting diode is scribed, the side surface of the light emitting diode is smoothly scribed by scribing in the crystal lattice direction of the substrate. However, according to this method, while the outer surface of the light emitting diode is clean and a reproducible process is obtained, the light emitted from the active layer due to total internal reflection of the substrate is not emitted to the outside of the light emitting diode, and is trapped inside to emit light. The problem of low efficiency is caused.

The present invention is to overcome the above-mentioned problems, to provide a light emitting diode with a concave-convex shape and a method of reporting the same to reduce the loss due to light totally reflected inside the substrate, to improve the luminous efficiency.

According to an aspect of the invention, preparing a substrate; Sequentially forming an n-type semiconductor layer, an active layer, and a p-type semiconductor layer on the substrate; And scribing the substrate in units of individual light emitting chips, wherein the scribing comprises scribing the substrate in a direction different from a crystal lattice direction of the substrate. This is provided.

The scribing of the substrate may include scribing the substrate by 1 to 5 degrees out of the crystal lattice direction of the substrate.

The substrate is characterized in that the light-transmissive substrate.

According to another aspect of the invention, a light emitting diode manufactured according to any one of the above manufacturing method, the light emitting diode comprises a substrate, an n-type semiconductor layer formed on the substrate; Active layer; And a p-type semiconductor layer, the light emitting diode having irregularities formed on at least one side of the light emitting diode is provided.

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

2 is a plan view of a light emitting diode according to an exemplary embodiment of the present invention, and FIG. 3 is a cross-sectional view of the light emitting diode shown in FIG. 2 taken along the line I-I.

2 and 3, the light emitting diode includes a substrate 110, an n-type semiconductor layer 120, an active layer 130, a p-type semiconductor layer 140, a p electrode 150, a bonding pad 155, n electrode 160 and unevenness 170.

The n-type semiconductor layer 120, the active layer 130, and the p-type semiconductor layer 140 are sequentially stacked on the substrate 110. The p electrode 150 is formed on the p-type semiconductor layer 140, and the bonding pad 155 is formed on the p electrode 150. The n electrode 160 is formed on the exposed n-type semiconductor layer 120 after exposing a predetermined region of the n-type semiconductor layer 120 through mesa etching. The active layer 130 is formed of a quantum well structure in which a well layer (not shown) having a small energy band gap and a barrier layer (not shown) having a larger energy band gap than a well layer are alternately stacked. Can be.

The unevenness 170 is formed on at least one of the side surfaces of the light emitting diode. At this time, the unevenness 170 may be formed in a sawtooth shape as shown in the figure, the shape of the unevenness is not limited thereto, and may be variously modified, the unevenness 170 may be a regular form, It may be formed in an irregular shape. When the irregularities 170 are sequentially formed on the substrate 110, the n-type semiconductor layer 120, the active layer 130, and the p-type semiconductor layer 140 are scribed in units of individual light emitting chips. The substrate 110 may be formed by scribing the substrate 110 in a direction deviated from the crystal lattice direction. In the case of the present embodiment, the scribing direction is set by shifting the crystal lattice direction of the substrate by 1 degree to 5 degrees, but this angle range is not limited thereto and may be variously changed. As such, when the uneven surface 170 is formed on the side surface of the light emitting diode, the total reflection is reduced so that light from the active layer 130 can be more easily emitted to the outside through the side surface of the light emitting diode. As a result, the light extraction efficiency of the light emitting diode can be improved.

4 is a schematic cross-sectional view of a vertical light emitting diode according to another embodiment of the present invention. Referring to FIG. 4, the vertical light emitting diode includes a p electrode 260, a p type semiconductor layer 250, an active layer 240, an n type semiconductor layer 230, an n electrode 270, and an unevenness 280. do. As described in the above embodiment, the unevenness 2800 may be formed by scribing in a direction that is deviated from the crystal lattice direction of the substrate when scribing by individual light emitting chip units.

5 to 8 illustrate a method of manufacturing a light emitting diode according to an embodiment of the present invention.

Referring to FIGS. 5 to 8, a light emitting diode manufacturing method is described. First, a substrate 110 having a predetermined crystal lattice direction is prepared (FIG. 5). At this time, the substrate 110 prepares a light transmissive substrate such as sapphire, ZnO, Spinel or MgAl ₂ O ₄ .

Next, an n-type semiconductor layer, an active layer, a p-type semiconductor layer, and the like are sequentially formed on the substrate 110 to form a light emitting diode (FIG. 6).

Then, the substrate 110 is scribed in units of individual light emitting chips. At this time, the scribing directions S1 and S2 are set in a direction different from the crystal lattice direction of the substrate, that is, shifted by a predetermined angle θ. In the case of this embodiment, the scribing direction is set to be shifted by 1 to 5 degrees from the crystal lattice direction.

As described above, when the scribing direction is set to be offset from the crystal lattice direction of the substrate, and scribing is performed, the scribing is performed without performing any additional process in order to form an uneven pattern on the side surface of the light emitting diode. When the ice process is performed, as shown in FIG. 8, a light emitting diode having irregularities may be obtained.

What has been described above is only an exemplary embodiment of the light-emitting diode and the manufacturing method of the unevenness formed in accordance with the present invention, the present invention is not limited to the above embodiment, as claimed in the following claims, Without departing from the gist of the invention, anyone of ordinary skill in the art to which the present invention will have the technical spirit of the present invention to the extent that various modifications can be made.

As described above, according to the present invention, by scribing the substrate out of the crystal lattice direction of the substrate, irregularities can be formed on the side surface of the light emitting diode without a separate unevenness forming process.

In addition, by forming the irregularities on the side surface of the light emitting diode, it is possible to emit light totally reflected inside the substrate to the outside of the light emitting diode, thereby improving the luminous efficiency of the light emitting diode.

Claims (4)

Preparing a substrate; Sequentially forming an n-type semiconductor layer, an active layer, and a p-type semiconductor layer on the substrate; And Scribing the substrate in units of individual light emitting chips to manufacture a light emitting diode; The scribing may include forming irregularities on at least one side of the light emitting diode by scribing the substrate by 1 to 5 degrees off the crystal lattice direction of the substrate. delete The method of claim 1, The substrate is a light emitting diode manufacturing method, characterized in that the transparent substrate. A light emitting diode manufactured according to the method according to claim 1 or 3, The light emitting diode includes a substrate, an n-type semiconductor layer, an active layer, and a p-type semiconductor layer sequentially formed on the substrate, The unevenness is formed on at least one side of the side surface of the light emitting diode.

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