KR20160053255A - Substrate for nitride semiconductor growth, method for manufacturing the substrate and nitride semiconductor light emitting device using the substrate - Google Patents

Abstract

Disclosed are a substrate for nitride semiconductor growth including a phosphor, a manufacturing method thereof, and a nitride semiconductor light emitting device using the same. According to the present invention, the nitride semiconductor light emitting device comprises: a growth substrate having first and second surfaces; and a light emitting structure composed of an epitaxially-grown multilayered nitride semiconductor on the first surface of the growth substrate and configured to emit light with a first wavelength. The growth substrate includes a phosphor therein, excited by the light with the first wavelength and configured to generate light with a second wavelength. According to the present invention, white light is able to be implemented in an element level, not a package level, by using the growth substrate including the phosphor therein.

Description

TECHNICAL FIELD [0001] The present invention relates to a substrate for growing a nitride semiconductor, a method of manufacturing the same, and a nitride semiconductor light emitting device using the same. BACKGROUND OF THE INVENTION [0002]

The present invention relates to a nitride semiconductor light emitting device, and more particularly, to a substrate for growing a nitride semiconductor including a phosphor, a method of manufacturing the same, and a nitride semiconductor light emitting device using the same.

A light emitting device is a device using a light emitting phenomenon occurring when electrons and holes are re-combined. As a typical light emitting device, there is a nitride semiconductor light emitting device using a nitride semiconductor such as GaN. The nitride semiconductor light emitting device has a wide band gap and can realize various color light, and has excellent thermal stability and is applied to many fields.

In general, the nitride semiconductor light emitting device has a structure in which an active layer is formed between an n-type nitride semiconductor layer and a p-type nitride semiconductor layer, and each of these layers is formed by epi growth of a nitride semiconductor on a growth substrate do.

On the other hand, in the nitride semiconductor light emitting device itself, light having a single color such as blue, green or red is emitted, and in order to realize white light, a phosphor emitting light of a complementary color and a color emitted from the light emitting device is required. These phosphors are mainly included in the polymer composition during the molding process for the package.

Background art related to the present invention is a phosphor-containing substrate for LEDs disclosed in Korean Patent Laid-Open Publication No. 10-2011-0085377 (published on July 27, 2011), an LED package using the substrate, and a method of manufacturing each of these.

It is an object of the present invention to provide a substrate for growing a nitride semiconductor including a phosphor, a method of manufacturing the same, and a nitride semiconductor light emitting device using the same.

According to an aspect of the present invention, there is provided a substrate for growing a nitride semiconductor, comprising: a substrate base material having a nitride semiconductor growth surface; And a phosphor dispersed in the substrate base material.

At this time, the phosphor preferably has a particle diameter of 10 mu m or less.

It is preferable that the phosphor is dispersed at a position within 600 占 퐉 from the growth surface.

According to an aspect of the present invention, there is provided a method of manufacturing a substrate for growing a nitride semiconductor, comprising: (a) implanting a phosphor into a substrate base material by implantation; And (b) heat treating the substrate material into which the phosphor is injected to recover crystallinity of the substrate material.

At this time, the phosphor preferably has a particle diameter of 50 nm or less.

According to another aspect of the present invention, there is provided a method of manufacturing a substrate for growing a nitride semiconductor, comprising: (a) applying a phosphor on a first substrate base material; (b) stacking a second substrate base material on the first substrate base material to which the phosphor is applied; And (c) bonding the first substrate and the second substrate through heat treatment.

At this time, the phosphor preferably has a particle diameter of 50 mu m or less.

According to another aspect of the present invention, there is provided a nitride semiconductor light emitting device including: a growth substrate having a first surface and a second surface; And a light emitting structure formed of a multi-layered nitride semiconductor epitaxially grown on a first surface of the growth substrate, the light emitting structure generating light having a first wavelength, And a phosphor for generating light having a second wavelength is excited.

At this time, the nitride semiconductor light emitting device may have a structure in which the second surface of the growth substrate becomes a main light emitting surface.

In the case of the nitride semiconductor light emitting device according to the present invention, white light can be realized at an element level rather than a package level by using a growth substrate containing a phosphor inside.

Further, in the case of the substrate for growing a nitride semiconductor according to the present invention, the phosphor is dispersed in the substrate base material, so that the phosphor does not affect the nitride semiconductor epitaxial growth. As a result, it is possible to grow nitride semiconductors of high quality.

In addition, in the method of manufacturing a substrate for growing a nitride semiconductor according to the present invention, a phosphor can be easily formed inside a substrate base material by a phosphor implantation process or the like.

1 is a cross-sectional view schematically showing a substrate for growing a nitride semiconductor according to an embodiment of the present invention.
2 is a cross-sectional view schematically showing a nitride semiconductor light emitting device manufactured using the substrate for growing a nitride semiconductor shown in FIG.
FIG. 3 shows an example in which the nitride semiconductor light emitting device of FIG. 2 is implemented as a flip chip.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention, and the manner of achieving them, will be apparent from and elucidated with reference to the embodiments described hereinafter in conjunction with the accompanying drawings. It should be understood, however, that the invention is not limited to the disclosed embodiments, but is capable of many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, To fully disclose the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

Hereinafter, a substrate for growing a nitride semiconductor according to preferred embodiments of the present invention, a method of manufacturing the same, and a nitride semiconductor light emitting device using the same will be described in detail with reference to the accompanying drawings.

1 is a cross-sectional view schematically showing a substrate for growing a nitride semiconductor according to an embodiment of the present invention.

Referring to FIG. 1, the substrate 100 for growing a nitride semiconductor has a phosphor 120 dispersed in a substrate base material 110 having a growth surface 110a.

The substrate base material 110 may be formed of sapphire, Si, SiC, GaN, or the like, and is preferably formed of a sapphire material when considering the crystal quality of the epitaxially grown nitride semiconductor and the substrate cost.

The phosphor contributes to form mixed light such as white light. For example, if the light emitted from the active layer is blue light, and the phosphor is excited by blue light to emit yellow light, the light emitted to the outside becomes mixed light in which blue light and yellow light are mixed. At this time, since the blue light and the yellow light have a complementary color relationship, the mixed light in which the blue light and the yellow light are mixed can be a white light.

Various known phosphors such as a YAG-base phosphor, a silicate-base phosphor, and a sialon-base phosphor can be used as such a phosphor.

The phosphor preferably has a particle diameter of 10 mu m or less. When the phosphor size exceeds 10 탆, the crystallinity of the substrate base material is remarkably deteriorated, and the crystal quality of the nitride semiconductor which is epitaxially grown can also be deteriorated.

The region where the phosphor is dispersed may be a region adjacent to the growth surface 110a of the substrate base material, a region adjacent to a surface opposite to the growth surface of the substrate base material, an entire region of the substrate base material, and the like.

Among them, it is preferable that the phosphor is dispersed in the region adjacent to the growth surface 110a of the substrate base material as in the region indicated by d in Fig. That is, it is preferable that the density of the phosphor from the growth surface of the substrate base material to the center of the substrate base material in the thickness direction is larger than the density of the phosphor from the opposite surface of the growth surface of the substrate base material to the center portion in the thickness direction of the substrate base material. Accordingly, in the nitride semiconductor light emitting device, the wavelength can be changed as soon as possible before the light generated in the active layer escapes to the outside, thereby improving the efficiency of white light emission.

More preferably, the phosphor is dispersed in a region of 600 mu m or less in the thickness direction from the growth surface 110a of the substrate base material. In general, the thickness of the sapphire substrate is 650 탆. If the phosphor distribution area d exceeds 600 탆, the phosphor distribution becomes wider, and the efficiency of white light emission may be lowered compared with a case where the phosphor distribution is 600 탆 or less.

The nitride semiconductor growth substrate in which the phosphor is dispersed therein can be manufactured by the following method.

As a first method, a phosphor implantation method can be suggested.

Similar to ion implantation, this method can be performed by accelerating the phosphor and injecting the phosphor into the substrate base material, followed by heat treatment to recover the crystallinity of the substrate base material.

When the phosphor implantation is used, it is more preferable that the phosphor has a particle diameter of 50 nm or less. When the size of the phosphor is large, accelerated phosphor particles do not pass through the substrate surface when they collide with the substrate base material, and are mostly repelled.

On the other hand, the substrate base material heat treatment can be performed at approximately 500 to 1200 ° C. The rapid thermal annealing process, which is performed within 5 minutes, is preferable for the substrate base material heat treatment. This is because, when the phosphor is kept at a high temperature for a long time, its characteristics deteriorate.

As a second method, a phosphor coating and a substrate bonding method can be suggested.

In this method, a phosphor is applied on a first substrate base material by a method such as spin coating, a second substrate base material is laminated on a first substrate base material coated with a phosphor, and then the first substrate and the second substrate are heat- And bonding it to each other. The heat treatment is preferably, but not always, limited to a local heat treatment method using a laser capable of rapid thermal annealing.

As a third method, it is possible to suggest a method of mixing the phosphor forming the base material and the phosphor and sintering. However, this method requires long time baking at a high temperature, which causes a problem of degradation of the phosphor properties.

2 is a cross-sectional view schematically showing a nitride semiconductor light emitting device manufactured using the substrate for growing a nitride semiconductor shown in FIG.

Referring to FIG. 2, the nitride semiconductor light emitting device includes a growth substrate 100 and a light emitting structure 200.

In the growth substrate 100, the phosphor 120 is dispersed in the substrate base material 110 as described above.

The light emitting structure 200 includes a first conductive type nitride semiconductor layer 210, an active layer 220, and a second conductive type nitride semiconductor layer 230. In addition, electrodes 240a and 240b for injecting carriers into the first conductive type nitride semiconductor layer 210 and the second conductive type nitride semiconductor layer 230 may be formed.

2, the first conductive type nitride semiconductor layer 210 is formed of n-type GaN, the second conductive type nitride semiconductor layer 230 is formed of p-type GaN, the active layer 220 is formed of multiple quantum wells MQW, Structure, a variety of known structures and materials may be used as the light emitting structure structure.

A light emitting structure 200 formed of such a multilayer nitride semiconductor is formed through epitaxial growth on a first surface of a growth substrate 100 having a first surface (growth surface) and a second surface.

The light emitting structure generates light having the first wavelength. Then, the phosphor in the growth substrate is excited by the light having the first wavelength to generate light having the second wavelength.

A preferred example of the nitride semiconductor light emitting device according to the present invention is that the second surface of the growth substrate is a main light emitting surface. For example, in the nitride semiconductor light emitting device as shown in FIG. 2, the reflective layer 310 may be formed on the second conductive type nitride semiconductor layer as shown in FIG. 3, Called flip chip, which is mounted on the submount substrate 330 through the materials 320a and 320b, can be used.

As described above, in the case of the nitride semiconductor light emitting device according to the present invention, by using a growth substrate in which a phosphor is contained by a phosphor implantation process or the like, white light can be realized at an element level instead of a package level.

Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. These changes and modifications may be made without departing from the scope of the present invention. Accordingly, the scope of the present invention should be determined by the following claims.

100: substrate for nitride semiconductor growth
110: substrate base material
110a: Growth side
120: Phosphor
200: light emitting structure
210: a first conductive type nitride semiconductor layer
220: active layer
230: second conductive type nitride semiconductor layer
240a and 240b:
310: Reflective layer
320: Bonding or soldering material
330: Sub-mount substrate

Claims (10)

As a substrate for growing a nitride semiconductor,
A substrate base material having a nitride semiconductor growth surface; And
And a phosphor dispersed in the substrate base material.
The method according to claim 1,
Wherein the phosphor has a particle diameter of 10 mu m or less.
The method according to claim 1,
Wherein the density of the phosphor from the growth surface of the substrate base material to the center of the substrate base material in the thickness direction is greater than the density of the phosphor from the opposite surface of the growth surface of the substrate base material to the center portion in the thickness direction of the substrate base material. .
The method according to claim 1,
Wherein the phosphor is dispersed at a position within 600 占 퐉 in the thickness direction from the growth surface.
(a) implanting a phosphor into the substrate base material by an implantation method; And
(b) annealing the substrate material into which the phosphor is injected to recover the crystallinity of the substrate material.
6. The method of claim 5,
Wherein the phosphor has a particle diameter of 50 nm or less.
(a) applying a phosphor on a first substrate base material;
(b) stacking a second substrate base material on the first substrate base material to which the phosphor is applied; And
(c) bonding the first substrate and the second substrate through heat treatment.
8. The method of claim 7,
Wherein the phosphor has a particle diameter of 50 mu m or less.
A growth substrate having a first side and a second side; And
And a light emitting structure formed of a multi-layered nitride semiconductor epitaxially grown on a first surface of the growth substrate, the light emitting structure generating light having a first wavelength,
And a phosphor that generates light having a second wavelength by being excited by the light having the first wavelength is dispersed in the growth substrate.
10. The method of claim 9,
Wherein the nitride semiconductor light emitting device has a structure in which a second surface of the growth substrate is a main light emitting surface.

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