KR20090108675A - Flip-chip structured group 3 nitride-based semiconductor light emitting diodes and methods to fabricate them - Google Patents

Abstract

PURPOSE: A group III nitride-based semiconductor light emitting diode having a flip chip structure is provided to perform a low driving voltage, a low leakage current, and a high external light emitting efficiency property. CONSTITUTION: A group III nitride-based semiconductor light emitting diode having a flip chip structure includes a growing substrate(10), a light emitting structure for an LED device, a super lattice structure(90), a first ohmic contact current spreading layer(100), a second ohmic contact current spreading layer, a third ohmic contact current spreading layer, a p-type schottky contact electrode pad, and an n-type ohmic contact electrode pad. The light emitting structure comprises a bottom nitride-based clad layer(20), a nitride-based active layer(30), and a top nitride-based clad layer(40). The super lattice structure is formed on a partial region or a whole region of a top surface of the top nitride-based clad layer of the light emitting structure for the LED device.

Description

Flip-chip structured group 3 nitride-based semiconductor light emitting diodes and methods to fabricate them}

The present invention provides a first ohmic contact current on an upper surface of a p-type In x Al y Ga 1-xy N (0≤x, 0≤y, x + y≤1) semiconductor, which is an upper nitride-based cladding layer of a light emitting structure for a light emitting diode device. An ohmic contact current spreading layer including a group III nitride-based conductive thin film structure as a spreading layer, a transparent conductive thin film structure as a second ohmic contact current spreading layer, and a reflective conductive thin film structure as a third ohmic contact current spreading layer Prior to growth formation, the p-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) semiconductor, which is the upper nitride-based cladding layer, and the first, second, and third A superlattice structure is inserted between the thin film structures composed of the ohmic contact current spreading layer to facilitate current injection in the vertical direction, and at the same time, the first or second ohmic contact current spreading. Drive voltage and external The overall performance of the light emitting diode device, including secondary light emission efficiency, can be effectively improved.

A light emitting diode (LED) device generates light by applying a current having a predetermined magnitude in the forward current to convert light into an active layer in a solid light emitting structure. Early research and development of LED devices formed compound semiconductors such as indium phosphorus (InP), gallium arsenide (GaAs), and gallium phosphorus (GaP) with p-i-n junction structure. While the LED emits light in the visible light region longer than the wavelength of green light, the device that emits blue and ultraviolet light has also been commercialized in recent years thanks to the research and development of group III nitride semiconductor materials. It is widely used in devices, light source devices, and environmental applications, and furthermore, it is possible to combine red, green, and blue LED device chips, or to use a phosphor in a short wavelength pumping LED device. A white light source LED that emits white light by grafting has been developed, and its application range is widening as a lighting device. In particular, LED devices using solid single crystal semiconductors are highly efficient in converting electrical energy to light energy, have an average lifespan of more than 5 years, and can greatly reduce energy consumption and maintenance costs. It is attracting attention.

Since a light emitting diode (hereinafter, referred to as a group III nitride semiconductor light emitting diode) device made of such a group III nitride semiconductor material system is generally grown on top of an insulating growth substrate (typically, sapphire), another group 3 Since two electrodes facing each other of the growth substrate cannot be provided like the Group-5 compound semiconductor light emitting diode device, two electrodes of the LED device must be formed on the crystal-grown semiconductor material system. A conventional structure of such a group III nitride semiconductor light emitting diode device is schematically illustrated in FIGS. 5 and 7.

First, referring to FIG. 5, a group III-nitride semiconductor light emitting diode device includes a lower nitride-based cladding made of a sapphire growth substrate 10 and an n-type conductive semiconductor material sequentially grown on an upper surface of the growth substrate 10. A layer 20, a nitride based active layer 30 and an upper nitride based cladding layer 40 made of a p-type conductive semiconductor material. The lower nitride-based cladding layer 20 may be formed of an n-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) semiconductor multilayer, and the nitride based active layer 30 Is composed of a multi-quantum well-structured semiconductor in which Group III-nitride-based In x Al y Ga 1-xy N (0≤x, 0≤y, x + y≤1) Can be. In addition, the upper nitride-based cladding layer 40 may be formed of a p-type In x Al y Ga 1-x-y N (0 ≦ x, 0 ≦ y, x + y ≦ 1) semiconductor multilayer. In general, the lower nitride-based cladding layer / nitride-based active layer / upper nitride-based cladding layer 20, 30, or 40 formed of the group III-nitride-based semiconductor single crystal is a device such as MOCVD, MBE, HVPE, sputter, or PLD. Can be grown using. At this time, prior to growing the n-type In x Al y Ga 1-xy N semiconductor, which is the lower nitride-based cladding layer 20, in order to improve lattice matching with the sapphire growth substrate 10, such as AlN or GaN The buffer layer 201 may be formed therebetween.

As described above, since the sapphire growth substrate 10 is an electrically insulating material, both electrodes of the LED element should be formed on the same upper surface of the single crystal semiconductor growth direction. For this purpose, the upper nitride-based cladding layer 40 and the nitride-based A portion of the active layer 30 is etched (ie, etched) to expose a portion of the upper nitride cladding layer 20 to the atmosphere, and the n-type In, the lower nitride-based cladding layer 20 exposed to the atmosphere, is exposed. An n-type ohmic contact interface electrode and an electrode pad 80 are formed on the x Al y Ga 1-xy N semiconductor upper surface.

In particular, since the upper nitride-based cladding layer 40 has a relatively high sheet resistance due to low carrier concentration and small mobility, prior to forming the p-type electrode 70, There is a need for additional materials capable of forming the ohmic contact current spreading layer 501. In contrast, US Pat. No. 5,563,422 discloses a p-type In x Al y Ga 1-xy N (40) semiconductor, which is an upper nitride-based cladding layer 40 positioned on an upper layer of a light emitting structure for a group III nitride semiconductor light emitting diode device. Before forming the p-type electrode 80 on the upper surface, nickel-gold oxidized to form an ohmic contact current spreading layer 501 forming an ohmic contact interface having a low specific contact resistance in the vertical direction. A material composed of (Ni-O-Au) has been proposed.

The ohmic contact current spreading layer 501 is disposed on the upper surface of the p-type In x Al y Ga 1-xy N semiconductor, which is the upper nitride-based cladding layer 40, while simultaneously improving current spreading in the horizontal direction. In addition, by forming an ohmic contact interface having a low specific contact resistance in the vertical direction, an effective current injection can be performed, thereby improving the electrical characteristics of the light emitting diode device. However, the ohmic contact current spreading layer 501 composed of oxidized nickel-gold has a low transmittance of 70% on average even after the heat treatment, and this low light transmittance is when the light generated by the light emitting diode device is emitted to the outside. It absorbs large amounts of light, reducing the overall external luminous efficiency.

As described above, in order to obtain a high-brightness light emitting diode device through the high light transmittance of the ohmic contact current spreading layer 501, various kinds including the recently-oxidized nickel-gold (Ni-O-Au) material Instead of the ohmic contact current spreading layer 501 formed of a translucent metal or alloy, a method of forming a transparent conductive material such as indium tin oxide (ITO) or zinc oxide (ZnO), which has a transmittance of 90% or more, has been proposed. . However, the transparent conductive material is a p-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) semiconductor, which is the upper nitride-based cladding layer 40 (~ 7.5 eV or more). Small work function (4.7 ~ 6.1eV), and direct deposition on top of p-type In x Al y Ga 1-xy N semiconductor and subsequent process including heat treatment, Shoki with large specific contact resistance instead of ohmic contact interface The formation of a schottky contact interface requires a new transparent conductive material or fabrication process that can solve the above problems.

The transparent conductive material such as ITO or ZnO is formed on the upper surface of the p-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) semiconductor of the upper nitride-based cladding layer 40. In order to be able to fulfill its role as a good ohmic contact current spreading layer 501, recently, YK Su et al. Have described the transparent electroconductive material described above in various documents as the p-type In x Al y as the upper nitride-based cladding layer 40. Prior to the direct deposition of Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) semiconductors, a current spreading layer having an ohmic contact interface via a superlattice structure 501) Forming technology is proposed.

As shown in FIG. 6, the superlattice structure has two layers a1 and b1 of a well and b1 and a barrier a1 in a multi-quantum well structure. Although the points repeated periodically in this one pair are similar, the barrier (a1) thickness of the multi-quantum well structure is relatively thicker than the thickness of the well (b1), while the two layers constituting the superlattice structure. (a2, b2) all have a thin thickness of 5 nm or less. Due to the above characteristics, the multi-quantum well structure is different from the role of confining electrons or holes, which are carriers, to the well b1 located between the thick barriers a1. It helps to facilitate transport.

Using the superlattice structure proposed by YK Su et al., A light emitting diode device having an ohmic contact current spreading layer 60 will be described with reference to FIG. 7. A group III nitride semiconductor light emitting diode device is a sapphire growth substrate ( 10) an upper nitride-based cladding layer formed of a lower nitride-based cladding layer 20 formed of an n-type conductive semiconductor material, an nitride-based active layer 30, and a p-type conductive semiconductor material formed on an upper surface of the growth substrate 10 ( 40), and superlattice structure 90. In particular, the superlattice structure 90 is in-situ with the same growth equipment as the lower nitride-based cladding layer 20, the nitride-based active layer 30, and the upper nitride-based cladding layer 40. To grow and form. The lower nitride-based cladding layer 20 may be formed of an n-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) semiconductor multilayer, and the nitride based active layer 30 Is a group III-nitride based In x Al y Ga 1-xy N (0≤x, 0≤y, x + y≤1) semiconductor multilayer composed of different composition of multi-quantum well structure. have. The upper nitride-based cladding layer 40 may be composed of a p-type In x Al y Ga 1-x-y N (0 ≦ x, 0 ≦ y, x + y ≦ 1) semiconductor multilayer. In addition, the superlattice structure 90 is a group III-nitride-based In x Al y Ga 1-xy N (0≤x, 0≤y, x + y≤1) semiconductor or other conductive plate composed of different compositions. A group III-nitride-based In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) semiconductor layer having a dopant may be formed.

P-type In x Al y Ga 1-xy N (0 ≦ x, 0), which is the upper nitride-based cladding layer 40, according to the composition and dopant type of the superlattice structure 90 ≤y, x + y≤1) Lower the dopant activation energy of the semiconductor to increase the net effective hole concentration, or through quantum mechanical tunneling conduction through energy bandgap engineering It is known to form an ohmic contact interface through a mechanical tunneling transport phenomenon.

In general, the lower nitride-based cladding layer / nitride-based active layer / the upper nitride-based cladding layer / superlattice structure 20, 30, 40, or 90 formed of the group III-nitride semiconductor single crystal is MOCVD, MBE, HVPE, or sputter. Or a device such as a PLD. At this time, prior to growing the n-type In x Al y Ga 1-xy N semiconductor of the lower nitride-based cladding layer 20, in order to improve lattice matching with the sapphire growth substrate 10, such as AlN or GaN The buffer layer 201 may be formed therebetween.

However, the material used for the ohmic contact current spreading layer 501 or 60 made of a transparent electroconductive material positioned on the upper nitride-based cladding layer 40 has a trade-off relationship between transmittance and electrical conductivity. have. In other words, if the thickness of the ohmic contact current spreading layer 501 or 60 is reduced in order to increase the transmittance, the electrical conductivity decreases conversely, increasing the series resistance of the group III nitride semiconductor light emitting diode device. For this reason, there exists a problem that it becomes a cause of the element reliability fall.

Therefore, a method of not using an ohmic contact current spreading layer composed of a transparent conductive material, and in the case of an optically transparent growth substrate, an electrically conductive material having high reflectance on the upper nitride-based cladding layer of the light emitting structure for a light emitting diode device A structure for forming the configured ohmic contact current spreading layer 502 can be considered. This is a cross-sectional view of the group III-nitride semiconductor light emitting diode device of the flip-chip structure shown in FIG.

As shown, the group III nitride semiconductor light emitting diode device of the flip chip structure is formed of an optically transparent sapphire growth substrate 10 and an n-type conductive semiconductor material sequentially grown on the upper surface of the growth substrate 10. The nitride-based cladding layer 20, the nitride-based active layer 30, and the upper nitride-based cladding layer 40 made of a p-type conductive semiconductor material are included. An ohmic contact current spreading layer 502 formed of an electrically conductive material having a high reflectance is formed on the upper nitride-based cladding layer 40, and light generated from the nitride-based active layer 30, which is a light emitting structure for a light emitting diode device, is formed. Is reflected in the opposite direction using the ohmic contact current spreading layer 502 having a high reflectance, and emits light toward the optically transparent growth substrate 10.

In general, a light emitting diode device that is widely used using a group III nitride semiconductor is generated using ultraviolet light, blue light, or green light using InGaN, AlGaN, etc. in the nitride active layer 30. 10) is sapphire. Since the sapphire used as the growth substrate 10 is a material having a fairly wide band gap, all of the sapphire is transparent to the light emitted from the group III nitride semiconductor LED device. For this reason, in particular, in the group III-nitride semiconductor light emitting diode device, the above-described flip chip structure can be said to be a very effective means. However, the upper nitride cladding layer 40 having p-type conductivity forms an ohmic contact interface and has high reflectance. The substance having is limited. In general, metal materials having high reflectivity are silver (Ag), aluminum (Al), and rhodium (Rh). The silver (Ag) and rhodium (Rh) and alloys associated with them exhibit good ohmic contact interfaces with the upper nitride based cladding layer 40, but the metals or alloys of these materials emit light for the light emitting diode device. There is a problem in that a diffusion phenomenon of material movement occurs inside the structure, and the operation voltage of the light emitting diode device is lowered and the reliability is lowered. In addition, thermally unstable silver (Ag), rhodium (Rh), and their associated alloys exhibit low reflectance to ultraviolet light, which is a short wavelength region of 400 nm or less, resulting in ohmic contact current of the light emitting diode device for ultraviolet light. It is not desirable as the spreading layer 502 material. On the other hand, although the aluminum (Al) and its related alloys have a high reflectance up to the ultraviolet region, they can be used because they form a schottky contact interface with the upper nitride-based cladding layer 40 having a p-type conductivity, which is not a desirable ohmic contact interface. There is no state. Therefore, in order to realize a group III nitride semiconductor light emitting diode device having a flip chip structure, an ohmic contact current spreading layer having an ohmic contact interface and a high reflectance on the upper nitride cladding layer 40 having p-type conductivity ( There is a need to develop materials or structures capable of forming 502.

The present invention relates to an upper surface of a p-type In x Al y Ga 1-xy N (0≤x, 0≤y, x + y≤1), which is an upper nitride-based cladding layer of a light emitting structure for a group III nitride semiconductor light emitting diode device. P-type In, an upper nitride-based cladding layer of the light emitting structure for group III-nitride semiconductor light emitting diode devices, is recognized to solve the problem occurring when forming an ohmic contact current spreading layer having an ohmic contact interface and high reflectance. x Al y Ga 1-xy N (0≤x, 0≤y, x + y≤1) A thin film structure including a superlattice structure, first, second, and third ohmic contact current spreading layers is formed on an upper surface of a semiconductor. The present invention provides a group III-nitride semiconductor light emitting diode device having a flip-chip structure having low driving voltage, low leakage current, and high external light emitting efficiency, and a method of manufacturing the same.

The present invention is a growth substrate; A lower nitride cladding layer made of an n-type conductive group III-nitride semiconductor on the upper surface of the growth substrate, a nitride active layer made of another group III-nitride-based semiconductor material, and a group III nitride-based semiconductor of p-type conductivity A light emitting structure for a light emitting diode device composed of an upper nitride cladding layer; A superlattice structure formed on an upper surface of the light emitting structure for the light emitting diode device; A group III-nitride semiconductor light emitting diode device having a flip chip structure, comprising: a thin film structure including first, second, and third ohmic contact current spreading layers formed on an upper surface of the superlattice structure.

The superlattice structure is a multi-layer composed of group 2, 3, or 4 nitrides having different dopants and composition elements,

The ohmic contact current spreading layer is a group III nitride-based conductive thin film structure that is a first ohmic contact current spreading layer, a transparent conductive thin film structure that is a second ohmic contact current spreading layer, and a third ohmic contact current spreading layer. A group III-nitride semiconductor light emitting diode device is characterized by comprising a conductive thin film structure.

The present invention is a growth substrate; A lower nitride cladding layer made of an n-type conductive group III-nitride semiconductor on the upper surface of the growth substrate, a nitride active layer made of another group III-nitride-based semiconductor material, and a group III nitride-based semiconductor of p-type conductivity A light emitting structure for a light emitting diode device composed of an upper nitride cladding layer; A superlattice structure formed on an upper surface of the light emitting structure for the light emitting diode device; A group III-nitride semiconductor light emitting diode device having a flip chip structure, comprising: a thin film structure including first, second, and third ohmic contact current spreading layers formed on an upper surface of the superlattice structure.

The superlattice structure is a multi-layer composed of group 2, 3, or 4 nitrides having different dopants and composition elements,

The ohmic contact current spreading layer is a group III nitride-based conductive thin film structure that is a first ohmic contact current spreading layer, a transparent conductive thin film structure that is a second ohmic contact current spreading layer, and a third ohmic contact current spreading layer. A group III-nitride semiconductor light emitting diode device is characterized by comprising a conductive thin film structure.

In order to improve the light extraction efficiency by changing the incident angle of the light generated by the light emitting diode device, a light extraction structure having a surface uneven process is introduced on the upper surface of the first or second ohmic contact current spreading layer Another group III-nitride semiconductor light emitting diode device is proposed.

The present invention provides a light emitting device using a group III nitride-based semiconductor represented by the formula In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) as a structural means for achieving the above object. In the method of manufacturing a diode (hereinafter, group 3 nitride-based semiconductor light emitting diode) device,

Preparing a growth substrate for growing a light emitting structure for a group III nitride semiconductor light emitting diode device;

A lower nitride cladding layer made of an n-type conductive group III nitride semiconductor material on the upper surface of the growth substrate, a nitride active layer made of a group III nitride semiconductor material composed of a different composition, and a group 3 p-conductive conductivity; Forming a light emitting structure for a group III nitride semiconductor light emitting diode device in which an upper nitride cladding layer made of a nitride semiconductor material is sequentially stacked and grown;

Forming a superlattice structure on an upper surface of a p-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) semiconductor, which is an upper nitride-based cladding layer of the light emitting structure for the light emitting diode device ;

Forming a first ohmic contact current spreading layer on an upper surface of the superlattice structure;

Forming a second ohmic contact current spreading layer on an upper surface of the first ohmic contact current spreading layer;

Forming a third ohmic contact current spreading layer on an upper surface of the second ohmic contact current spreading layer;

A portion of the first, second, and third ohmic contact current spreading layer, a superlattice structure, an upper nitride based cladding layer, a nitride based cladding layer, and a lower nitride based cladding layer is removed, and the lower nitride based cladding layer is removed. Exposing to air and forming an n-type ohmic contact electrode and an electrode pad on a portion of an upper surface of the lower nitride-based cladding layer; And

And forming a p-type schottky contact electrode and an electrode pad on a portion of an upper surface of the first, second, or third ohmic contact current spreading layer.

The present invention provides a group III nitride-based semiconductor represented by the chemical formula In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) as another means for achieving the above object. In the light emitting diode (hereinafter referred to as group III nitride semiconductor light emitting diode) device manufacturing method,

Preparing a growth substrate for growing a light emitting structure for a group III nitride semiconductor light emitting diode device;

A lower nitride cladding layer made of an n-type conductive group III nitride semiconductor material on the upper surface of the growth substrate, a nitride active layer made of a group III nitride semiconductor material composed of a different composition, and a group 3 p-conductive conductivity; Forming a light emitting structure for a group III nitride semiconductor light emitting diode device in which an upper nitride cladding layer made of a nitride semiconductor material is sequentially stacked and grown;

Forming a superlattice structure on an upper surface of a p-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) semiconductor, which is an upper nitride-based cladding layer of the light emitting structure for the light emitting diode device ;

Forming a first ohmic contact current spreading layer on an upper surface of the superlattice structure;

Forming a second ohmic contact current spreading layer on an upper surface of the first ohmic contact current spreading layer;

A portion of the first and second ohmic contact current spreading layer, the superlattice structure, the upper nitride based cladding layer, the nitride based active layer, and the lower nitride based cladding layer was removed and the lower nitride based cladding layer was exposed to the atmosphere. Next, forming an n-type ohmic contact electrode and an electrode pad on a portion of the upper surface of the lower nitride-based cladding layer;

Forming a third ohmic contact current spreading layer on an upper surface of the second ohmic contact current spreading layer; And

And forming a p-type schottky contact electrode and an electrode pad on a portion of an upper surface of the first, second, or third ohmic contact current spreading layer.

The present invention provides a group III nitride-based semiconductor represented by the chemical formula In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) as another means for achieving the above object. In the light emitting diode (hereinafter referred to as group III nitride semiconductor light emitting diode) device manufacturing method,

Preparing a growth substrate for growing a light emitting structure for a group III nitride semiconductor light emitting diode device;

A lower nitride cladding layer made of an n-type conductive group III nitride semiconductor material on the upper surface of the growth substrate, a nitride active layer made of a group III nitride semiconductor material composed of a different composition, and a group 3 p-conductive conductivity; Forming a light emitting structure for a group III nitride semiconductor light emitting diode device in which an upper nitride cladding layer made of a nitride semiconductor material is sequentially stacked and grown;

Forming a superlattice structure on an upper surface of a p-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) semiconductor, which is an upper nitride-based cladding layer of the light emitting structure for the light emitting diode device ;

Forming a first ohmic contact current spreading layer on an upper surface of the superlattice structure;

After removing a portion of the first ohmic contact current spreading layer, the superlattice structure, the upper nitride-based cladding layer, the nitride-based active layer, and the lower nitride-based cladding layer, the lower nitride-based cladding layer is exposed to the air. Forming an n-type ohmic contact electrode and an electrode pad on a portion of an upper surface of the lower nitride clad layer;

Forming a second ohmic contact current spreading layer on an upper surface of the first ohmic contact current spreading layer;

Forming a third ohmic contact current spreading layer on an upper surface of the second ohmic contact current spreading layer; And

And forming a p-type schottky contact electrode and an electrode pad on a portion of an upper surface of the first, second, or third ohmic contact current spreading layer.

Instead of the superlattice structure having a multilayer structure, the superlattice structure may be formed of an n-type conductive InGaN single layer or a p-type conductive InGaN single layer having a thickness of 5 nm or less.

The ohmic contact current spreading layer may include a first ohmic contact current spreading layer of a group III nitride-based conductive thin film structure, a second ohmic contact current spreading layer of a transparent conductive thin film structure, and a third ohmic contact current of a reflective conductive thin film structure. It is comprised by the spreading layer.

Prior to forming the third ohmic contact current spreading layer, a light extraction structure in which surface irregularities are introduced may be formed on an upper surface of the first or second ohmic contact current spreading layer formed of the group III-nitride-based conductive thin film structure. It may be.

The lower nitride based cladding layer, the nitride based active layer, the upper nitride based cladding layer, the superlattice structure, and the first ohmic contact current spreading layer are in-situ using MOCVD, MBE, or HVPE equipment. Form a continuous growth.

In addition, the lower nitride-based cladding layer, the nitride-based active layer, the upper nitride-based cladding layer, and the superlattice structure is continuously grown in-situ state using MOCVD, MBE, or HVPE equipment, and then The first ohmic contact current spreading layer may be formed in an ex-situ state using MOCVD, MBE, HVPE, sputter, evaporator, or PLD equipment.

As described above, the present invention is a p-type In x Al, which is an upper nitride cladding layer of a light emitting structure for a light emitting diode device having a flip chip structure in a group 3 nitride semiconductor light emitting device (light emitting diode) device having a flip chip structure. y Ga 1-xy N (0≤x, 0≤y, x + y≤1) A first ohmic contact current spreading layer and a transparent conductive thin film composed of a superlattice structure and a group III-nitride-based conductive thin film structure on a semiconductor upper surface In addition to the good electrical characteristics of the entire LED device having a good flip chip structure by combining a second ohmic contact current spreading layer composed of a structure and a third ohmic contact current spreading layer composed of a reflective conductive thin film structure, light transmittance characteristics are improved. There is an excellent effect that can improve the brightness of the light emitting device.

In addition, in the group III-nitride semiconductor light emitting diode device of the flip chip structure having the light extraction structure, the first or second ohmic contact current spreading layer composed of the group III-nitride conductive thin film structure by wet or dry etching. Since the surface irregularities can be easily formed on the upper surface, there is an excellent effect of further improving the overall luminance characteristics of the LED device by minimizing the light totally reflected inside the light emitting structure for the flip-chip LED device.

Hereinafter, with reference to the accompanying drawings, it will be described in more detail with respect to the Group III nitride semiconductor light emitting diode device manufactured according to the present invention.

1 is a cross-sectional view showing a first embodiment of a light emitting structure for a group III-nitride semiconductor light emitting diode device having a flip chip structure invented by the present invention.

Referring to FIG. 1, a light emitting structure (A) for a light emitting diode device having a flip chip structure according to the first embodiment of the present invention, which is formed on the growth substrate 10, and has a buffer layer on an upper surface of the growth substrate 10. A lower nitride cladding layer 20 made of an n-type conductive semiconductor material (not shown), a nitride-based active layer 30, an upper nitride cladding layer 40 made of a p-type conductive semiconductor material, A superlattice structure 90, and a first ohmic contact current spreading layer 100.

The growth substrate 10 may be made of a material such as sapphire or silicon carbide (SiC).

The lower nitride-based cladding layer 20 formed of the n-type conductive semiconductor material may be formed of an In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) semiconductor multilayer. The growth substrate 10 may include a buffer layer (not shown) formed on the top surface. The lower nitride cladding layer 20 may be formed by doping silicon (Si).

The nitride-based active layer 30 is a region where electrons and holes, which are carriers, are recombined and include InGaN, AlGaN, GaN, AlInGaN, and the like.

In addition, the nitride-based active layer 30 may be a multilayer film in which a quantum well layer and a barrier layer are repeatedly formed. The energy bandgap of the material constituting the barrier layer of the nitride based active layer 30 is larger than that of the material constituting the well layer, and the thickness of the barrier layer is greater than the thickness of the well layer. Thick is common. The barrier layer and the well layer may be a binary, ternary, or quaternary compound nitride-based semiconductor represented by the formula In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1). have. Furthermore, the barrier layer and the well layer may be formed by doping silicon (Si) or magnesium (Mg). The emission wavelength of light emitted from the light emitting diode device is determined according to the kind of material constituting the quantum well layer of the nitride based active layer 30.

The upper nitride cladding layer 40 made of the p-type conductive semiconductor material may be formed of a p-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) semiconductor multilayer. have. The upper nitride cladding layer 40 may be formed by doping zinc (Zn) or magnesium (Mg).

The superlattice structure 90 is positioned on the upper nitride-based cladding layer 40 made of the p-type conductive semiconductor material, and has a p-type p-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y≤1) Lower the dopant activation energy of the semiconductor to increase the effective hole concentration, or quantum-mechanical tunneling transport through energy band-gap engineering Can cause.

The superlattice structure 90 is generally formed in multiple layers, and the thickness of each layer constituting the superlattice structure is 5 nm or less, and each layer is formed of InN, InGaN, InAlN, AlGaN, GaN, AlInGaN, AlN, SiC, SiCN. , MgN, ZnN, or SiN. In one example, the superlattice structure 90 includes InGaN / GaN, AlGaN / GaN, InGaN / GaN / AlGaN, AlGaN / GaN / InGaN.

Furthermore, each layer of the superlattice structure 90 may be formed by doping silicon (Si), magnesium (Mg), zinc (Zn), or the like.

The superlattice structure 90 composed of an n-type conductive InGaN single layer or a p-type conductive InGaN single layer having a thickness of 5 nm or less may be substituted for the superlattice structure 90 having a multilayer structure. have.

The first ohmic contact current spreading layer 100 includes a group III nitride-based conductive thin film structure. The group III nitride-based conductive thin film structure of the first ohmic contact current spreading layer 100 is represented by the formula In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1). It may be composed of a single layer or a multi-layer having a thickness of 6 nm or more. Further, the first ohmic contact current spreading layer 100 may be formed by doping silicon (Si), magnesium (Mg), zinc (Zn), or the like.

The light emitting structure A for the light emitting diode device of the flip chip structure is continuously grown in an in-situ state by using a device such as a MOCVD, MBE, HVPE, sputter, or PLD. Further, the lower nitride-based cladding layer 20, the nitride-based active layer 30, the upper nitride-based cladding layer 40, and the superlattice structure 90 of the light emitting structure A for the flip-chip light emitting diode device A are provided. The growth may be successively formed first in the in situ state, and then the first ohmic contact current spreading layer 100 may be grown on the upper surface of the superlattice structure 90 in an ex-situ state.

2 is a cross-sectional view showing a second embodiment of a light emitting structure for a group III-nitride semiconductor light emitting diode device having a flip chip structure invented by the present invention.

Referring to FIG. 2, a light emitting structure B for a light emitting diode device having a flip chip structure according to the first embodiment of the present invention, which is formed on the growth substrate 10 and has a buffer layer on an upper surface of the growth substrate 10. A lower nitride cladding layer 20 made of an n-type conductive semiconductor material (not shown), a nitride-based active layer 30, an upper nitride cladding layer 40 made of a p-type conductive semiconductor material, The super lattice structure 90 and the first ohmic contact current spreading layer 100 are repeatedly stacked.

The growth substrate 10 may be made of a material such as sapphire or silicon carbide (SiC).

The lower nitride-based cladding layer 20 formed of the n-type conductive semiconductor material may be formed of an In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) semiconductor multilayer. The growth substrate 10 may include a buffer layer (not shown) formed on the top surface. The lower nitride cladding layer 20 may be formed by doping silicon (Si).

The nitride-based active layer 30 is a region where electrons and holes, which are carriers, are recombined and include InGaN, AlGaN, GaN, AlInGaN, and the like.

In addition, the nitride-based active layer 30 may be a multilayer film in which a quantum well layer and a barrier layer are repeatedly formed. The energy bandgap of the material constituting the barrier layer of the nitride based active layer 30 is larger than that of the material constituting the well layer, and the thickness of the barrier layer is greater than the thickness of the well layer. Thick is common. The barrier layer and the well layer may be a binary, ternary, or quaternary compound nitride-based semiconductor represented by the formula In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1). have. Furthermore, the barrier layer and the well layer may be formed by doping silicon (Si) or magnesium (Mg). The emission wavelength of light emitted from the light emitting diode device is determined according to the kind of material constituting the quantum well layer of the nitride based active layer 30.

The upper nitride cladding layer 40 made of the p-type conductive semiconductor material may be formed of a p-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) semiconductor multilayer. have. The upper nitride cladding layer 40 may be formed by doping zinc (Zn) or magnesium (Mg).

The superlattice structure 90 repeatedly stacked on the upper nitride cladding layer 40 is disposed on an upper surface of the upper nitride cladding layer 40 made of the p-type conductive semiconductor material. x Al y Ga 1-xy N (0≤x, 0≤y, x + y≤1) Lower the dopant activation energy of the semiconductor to increase the effective hole concentration, or band-gap engineering This can lead to quantum-mechanical tunneling transport.

The superlattice structure 90 is generally formed in multiple layers, and the thickness of each layer constituting the superlattice structure is 5 nm or less, and each layer is formed of InN, InGaN, InAlN, AlGaN, GaN, AlInGaN, AlN, SiC, SiCN. , MgN, ZnN, or SiN. In one example, the superlattice structure 90 includes InGaN / GaN, AlGaN / GaN, InGaN / GaN / AlGaN, AlGaN / GaN / InGaN.

Furthermore, each layer of the superlattice structure 90 may be formed by doping silicon (Si), magnesium (Mg), zinc (Zn), or the like.

The superlattice structure 90 composed of an n-type conductive InGaN single layer or a p-type conductive InGaN single layer having a thickness of 5 nm or less may be substituted for the superlattice structure 90 having a multilayer structure. have.

The first ohmic contact current spreading layer 100 repeatedly stacked on the superlattice structure 90 is composed of a group III nitride-based conductive thin film structure. The group III nitride-based conductive thin film structure of the first ohmic contact current spreading layer 100 is represented by the formula In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1). It may be composed of a single layer or a multi-layer having a thickness of 6 nm or more. Further, the first ohmic contact current spreading layer 100 may be formed by doping silicon (Si), magnesium (Mg), zinc (Zn), or the like.

The light emitting structure (B) for the light emitting diode device of the flip chip structure is continuously grown in an in-situ state by using a device such as MOCVD, MBE, HVPE, sputter, or PLD. Further, the lower nitride-based cladding layer 20, the nitride-based active layer 30, the upper nitride-based cladding layer 40, and the superlattice structure 90 of the light emitting structure B for the flip-chip light emitting diode device have a structure. Is first grown in an in-situ state first, and then grows the first ohmic contact current spreading layer 100 on the superlattice structure 90 in an ex-situ state. It may be formed.

3 is a cross-sectional view of a group III-nitride semiconductor light emitting diode device having a flip chip structure shown as the first embodiment manufactured by the present invention.

Referring to FIG. 3, a light emitting structure A for a light emitting diode device having a flip chip structure according to the first embodiment of the present invention is grown and formed on an upper surface of the growth substrate 10. In other words, the lower nitride-based cladding layer 20 made of an n-type conductive semiconductor material including a buffer layer (not shown) on the upper surface of the growth substrate 10, the nitride-based active layer 30, and an upper portion made of a p-type conductive semiconductor material The light emitting structure A for a light emitting diode element including the nitride cladding layer 40, the superlattice structure 90, and the first ohmic contact current spreading layer 100, and the second ohmic contact current spreading layer 120. And a third ohmic contact current spreading layer 130, a p-type schottky contact electrode and an electrode pad 70, and an n-type ohmic contact electrode and an electrode pad 80.

For example, the lower nitride-based cladding layer 20, the nitride-based active layer 30, the upper nitride-based cladding layer 40, the superlattice structure 90, and the first ohmic contact current spreading layer 100 may be formed. Continuous growth is formed in an in-situ state using MOCVD, MBE, or HVPE equipment, and the second and third ohmic contact current spreading layer 130 is formed using a sputter, evaporator, or PLD equipment. It is preferable to form in an ex-situ state.

The growth substrate 10 may be made of a material such as sapphire or silicon carbide (SiC).

The lower nitride-based cladding layer 20 formed of the n-type conductive semiconductor material may be formed of an In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) semiconductor multilayer. The growth substrate 10 may include a buffer layer (not shown) formed on the top surface. The lower nitride based cladding layer 20 may be formed by doping silicon (Si).

The nitride-based active layer 30 is a region where electrons and holes, which are carriers, are recombined and include InGaN, AlGaN, GaN, AlInGaN, and the like.

In addition, the nitride-based active layer 30 may be a multilayer film in which a quantum well layer and a barrier layer are repeatedly formed. The energy bandgap of the material constituting the barrier layer of the nitride based active layer 30 is larger than that of the material constituting the well layer, and the thickness of the barrier layer is greater than the thickness of the well layer. Thick is common. The barrier layer and the well layer may be a binary, ternary, or quaternary compound nitride-based semiconductor represented by the formula In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1). have. Furthermore, the barrier layer and the well layer may be formed by doping silicon (Si) or magnesium (Mg). The emission wavelength of light emitted from the light emitting diode device is determined according to the kind of material constituting the quantum well layer of the nitride based active layer 30.

The upper nitride cladding layer 40 made of the p-type conductive semiconductor material may be formed of a p-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) semiconductor multilayer. have. The upper nitride cladding layer 40 may be formed by doping zinc (Zn) or magnesium (Mg).

The light emitting diode device has a structure in which the lower nitride based cladding layer 20, the nitride based active layer 30, and the upper nitride based cladding layer 40 are sequentially stacked. The nitride-based active layer 30 is formed on a portion of the lower nitride-based cladding layer 20 formed of the n-type conductive semiconductor material, and is formed of a p-type conductive semiconductor material on the nitride-based active layer 30. An upper nitride cladding layer 40 is formed. Therefore, a portion of the upper surface of the lower nitride based cladding layer 20 is bonded to the nitride based active layer 30, and the remaining portion of the upper surface of the lower nitride clad layer 20 is exposed to the outside.

The superlattice structure 90 is located on a part or the entire region of the upper nitride-based cladding layer 40, and is generally formed in multiple layers. The thickness of each layer constituting the superlattice structure 90 is 5 nm or less. May be composed of InN, InGaN, InAlN, AlGaN, GaN, AlInGaN, AlN, SiC, SiCN, MgN, ZnN, or SiN. For example, the superlattice structure 90 includes silicon (Si) doped InGaN / GaN, AlGaN / GaN, InGaN / GaN / AlGaN, AlGaN / GaN / InGaN.

Furthermore, each layer of the superlattice structure 90 may be formed by doping silicon (Si), magnesium (Mg), zinc (Zn), or the like.

The superlattice structure 90 composed of an n-type conductive InGaN single layer or a p-type conductive InGaN single layer having a thickness of 5 nm or less may be substituted for the superlattice structure 90 having a multilayer structure. have.

The first ohmic contact current spreading layer 100 is formed of a group III nitride-based conductive thin film structure in a part or the entire area of the superlattice structure 90, and is emitted from the nitride-based active layer 30. Transmits light to the outside For example, MOCVD consists of group III nitride-based conductive materials such as silicon (Si) doped gallium nitride (GaN) and silicon (Si) doped aluminum gallium nitride (AlGaN) having a sheet resistance of 50 Ω / □ or less. , MBE, HVPE, sputter, or a single layer or multilayer thin film having a thickness of more than 6nm formed by using a device, such as PLD, the light emitted by uniformly dispersing the current input through the p-type schottky contact electrode and electrode pad 70 It plays a role of increasing efficiency.

The second ohmic contact current spreading layer 120 is formed of a transparent conductive thin film structure. The transparent conductive thin film structure of the second ohmic contact current spreading layer 120 is a material having a light transmittance of 70% or more at a wavelength band of 600 nm or less, such as ITO or ZnO, and a sheet resistance of 50 Ω / □ or less. It may be composed of a single layer or a multi-layer having the above thickness.

The third ohmic contact current spreading layer 130 is formed of a reflective conductive thin film structure. The reflective conductive thin film structure of the third ohmic contact current spreading layer 130 is a material having a light reflectivity of 70% or more in a wavelength band of 600 nm or less, such as Ag or Al, and a sheet resistance of 50 Ω / □ or less, and 200 nm It may be composed of a single layer or a multi-layer having the above thickness.

The p-type schottky contact electrode and the electrode pad 70 are positioned on a portion of an upper surface of the ohmic contact current spreading layer 100, 120, or 130, and the ohmic contact current spreading layer 100, 120, or 130. And a material for forming a schottky contact interface, for example, a metal such as Pd / Au, and may be formed by a lift off method. Pd / Au is used to improve adhesion to the ohmic contact current spreading layer 100, 120, or 130 as well as to show the desired Shoki of the ohmic contact current spreading layer 100, 120, or 130. A contact interface can be obtained.

The n-type ohmic contact electrode and the electrode pad 80 are formed on the exposed surface of the lower nitride-based cladding layer 20 made of an n-type conductive semiconductor material and may be formed using a lift-off method. The n-type ohmic contact electrode and the electrode pad 80 are made of a material for forming an ohmic contact interface with the lower nitride-based cladding layer 20, for example, a metal such as Cr / Al, and using Cr metal. In addition to improving adhesion, a desirable ohmic contact interface with the lower nitride-based cladding layer 20 can be obtained.

4 is a cross-sectional view of a group III-nitride semiconductor light emitting diode device of a flip chip structure shown as a second embodiment produced by the present invention.

Referring to FIG. 4, a light emitting structure A for a light emitting diode device having a flip chip structure according to the first embodiment of the present invention is grown and formed on an upper surface of the growth substrate 10. In other words, the lower nitride-based cladding layer 20 made of an n-type conductive semiconductor material including a buffer layer (not shown) on the upper surface of the growth substrate 10, the nitride-based active layer 30, and an upper portion made of a p-type conductive semiconductor material The light emitting structure A for a light emitting diode element including the nitride cladding layer 40, the superlattice structure 90, the first ohmic contact current sppping layer 100, and the light extraction structure 110, and the third ohmic contact And a current spray padding layer 130, a p-type schottky contact electrode and electrode pad 70, and an n-type ohmic contact electrode and electrode pad 80.

For example, the lower nitride-based cladding layer 20, the nitride-based active layer 30, the upper nitride-based cladding layer 40, the superlattice structure 90, and the first ohmic contact current spreading layer 100 may be formed. The MOCVD, MBE, or HVPE equipment is used to continuously grow and form in-situ, and the third ohmic contact current spreading layer 130 may be MOCVD, MBE, HVPE, sputter, evaporator, or PLD equipment. It is preferable to form in an ex-situ state using.

The growth substrate 10 may be made of a material such as sapphire or silicon carbide (SiC).

The lower nitride-based cladding layer 20 formed of the n-type conductive semiconductor material may be formed of an In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) semiconductor multilayer. The growth substrate 10 may include a buffer layer (not shown) formed on the top surface. The lower nitride cladding layer 20 may be formed by doping silicon (Si).

The nitride-based active layer 30 is a region where electrons and holes, which are carriers, are recombined and include InGaN, AlGaN, GaN, AlInGaN, and the like.

In addition, the nitride-based active layer 30 may be a multilayer film in which a quantum well layer and a barrier layer are repeatedly formed. The energy bandgap of the material constituting the barrier layer of the nitride based active layer 30 is larger than that of the material constituting the well layer, and the thickness of the barrier layer is greater than the thickness of the well layer. Thick is common. The barrier layer and the well layer may be a binary, ternary, or quaternary compound nitride-based semiconductor represented by the formula In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1). have. Furthermore, the barrier layer and the well layer may be formed by doping silicon (Si) or magnesium (Mg). The emission wavelength of light emitted from the light emitting diode device is determined according to the kind of material constituting the quantum well layer of the nitride based active layer 30.

The upper nitride cladding layer 40 made of the p-type conductive semiconductor material may be formed of a p-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) semiconductor multilayer. have. The upper nitride cladding layer 40 may be formed by doping zinc (Zn) or magnesium (Mg).

The light emitting diode device has a structure in which the lower nitride based cladding layer 20, the nitride based active layer 30, and the upper nitride based cladding layer 40 are sequentially stacked. The nitride-based active layer 30 is formed on a portion of the lower nitride-based cladding layer 20 made of the n-type conductive semiconductor material, and is formed of a p-type conductive semiconductor material on the nitride-based active layer 30. An upper nitride cladding layer 40 is formed. Therefore, a portion of the upper surface of the lower nitride based cladding layer 20 is bonded to the nitride based active layer 30, and the remaining portion of the upper surface of the lower nitride clad layer 20 is exposed to the outside.

The superlattice structure 90 is located on a part or the entire region of the upper nitride-based cladding layer 40, and is generally formed in multiple layers. The thickness of each layer constituting the superlattice structure 90 is 5 nm or less. May be composed of InN, InGaN, InAlN, AlGaN, GaN, AlInGaN, AlN, SiC, SiCN, MgN, ZnN, or SiN. For example, the superlattice structure 90 includes silicon (Si) doped InGaN / GaN, AlGaN / GaN, InGaN / GaN / AlGaN, AlGaN / GaN / InGaN.

Furthermore, each layer of the superlattice structure 90 may be formed by doping silicon (Si), magnesium (Mg), zinc (Zn), or the like.

The superlattice structure 90 composed of an n-type conductive InGaN single layer or a p-type conductive InGaN single layer having a thickness of 5 nm or less may be substituted for the superlattice structure 90 having a multilayer structure. have.

The first ohmic contact current spreading layer 100 is formed of a group III nitride-based conductive thin film structure in a part or the entire area of the superlattice structure 90, and is emitted from the nitride-based active layer 30. Transmits light to the outside For example, MOCVD is made of a Group III nitride-based conductive material such as silicon (Si) doped gallium nitride (GaN) or silicon (Si) doped aluminum gallium nitride (AlGaN) having a sheet resistance of 50 Ω / □ or less. , MBE, HVPE, sputter, or a single layer or multilayer thin film having a thickness of more than 6nm formed by using a device, such as PLD, the light emitted by uniformly dispersing the current input through the p-type schottky contact electrode and electrode pad 70 It plays a role of increasing efficiency.

The light extraction structure 110 is a surface introduced on the upper surface of the first or second ohmic contact current spreading layer 100 or 120 in order to emit as much of the light generated from the nitride based active layer 30 into the atmosphere as possible. It is a surface texture. The light extracting structure 110 forms a concave-convex shape having a predetermined shape and dimension on the surface of the first or second ohmic contact current spreading layer 100 or 120 by using wet or dry etching to emit light for a light emitting diode device. It is possible to further improve the overall brightness characteristics of the LED device by minimizing the light totally reflected inside the structure structure.

The second ohmic contact current spreading layer 120 is formed of a transparent conductive thin film structure. The transparent conductive thin film structure of the second ohmic contact current spreading layer 120 is a material having a light transmittance of 70% or more at a wavelength band of 600 nm or less, such as ITO or ZnO, and a sheet resistance of 50 Ω / □ or less. It may be composed of a single layer or a multi-layer having the above thickness.

The third ohmic contact current spreading layer 130 is formed of a reflective conductive thin film structure. The reflective conductive thin film structure of the third ohmic contact current spreading layer 130 is a material having a light reflectivity of 70% or more in a wavelength band of 600 nm or less, such as Ag or Al, and a sheet resistance of 50 Ω / □ or less, and 200 nm It may be composed of a single layer or a multi-layer having the above thickness.

The p-type schottky contact electrode and the electrode pad 70 are positioned in a portion of the upper surface of the light extraction structure 110 or the ohmic contact current spreading layer 100, 120, or 130, and the light extraction structure 110 or A material for forming a schottky contact interface with the ohmic contact current spreading layer 100, 120, or 130, for example, a metal such as Pd / Au, may be formed by a lift off method. Using Pd / Au not only improves adhesion to the light extraction structure 110 or ohmic contact current spreading layer 100, 120, or 130, but also preferably the light extraction structure 110 or ohmic contact. A schottky contact interface of the current spreading layer 100, 120, or 130 can be obtained.

The n-type ohmic contact electrode and the electrode pad 80 are formed on the exposed surface of the lower nitride-based cladding layer 20 made of an n-type conductive semiconductor material and may be formed using a lift-off method. The n-type ohmic contact electrode and the electrode pad 80 are made of a material for forming an ohmic contact interface with the lower nitride-based cladding layer 20, for example, a metal such as Cr / Al, and using Cr metal. In addition to improving adhesion, a desirable ohmic contact interface with the lower nitride-based cladding layer 20 can be obtained.

Although the preferred embodiments of the present invention have been described in detail above, those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom. Accordingly, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concept of the present invention as defined in the following claims also fall within the scope of the present invention.

1 is a cross-sectional view showing a first embodiment of a light emitting structure for a group III-nitride semiconductor light emitting diode device having a flip chip structure invented by the present invention;

2 is a cross-sectional view showing a second embodiment of a light emitting structure for a group III nitride semiconductor light emitting diode device having a flip chip structure invented by the present invention;

3 is a cross-sectional view showing a first embodiment of a group III-nitride semiconductor light emitting diode device having a flip chip structure manufactured according to the present invention;

4 is a cross-sectional view showing a second embodiment of a group III-nitride semiconductor light emitting diode device having a flip chip structure manufactured according to the present invention;

5 is a cross-sectional view showing a typical example of a group III-nitride semiconductor light emitting diode device according to the related art;

6 is a cross-sectional view for comparing and comparing a multi-quantum well structure and a superlattice structure,

7 is a cross-sectional view showing a representative example of a conventional Group 3 nitride-based semiconductor light emitting diode device,

8 is a cross-sectional view illustrating a representative example of a group III-nitride semiconductor light emitting diode device having a conventional flip chip structure.

Claims (45)

A growth substrate; A light emitting structure for a light emitting diode device comprising a lower nitride-based cladding layer made of an n-type conductive semiconductor material including a buffer layer formed on an upper surface of the growth substrate, a nitride-based active layer, and an upper nitride-based cladding layer made of a p-type conductive semiconductor material; ; A superlattice structure formed on a portion or the entire area of the upper nitride-based cladding layer of the light emitting structure for the light emitting diode device; A first ohmic contact current spreading layer formed on a portion or an entire area of the upper surface of the superlattice structure; A second ohmic contact current spreading layer formed on a portion or an entire area of an upper surface of the first ohmic contact current spreading layer; A third ohmic contact current spreading layer formed on a portion or an entire area of an upper surface of the second ohmic contact current spreading layer; A p-type schottky contact electrode and an electrode pad formed on a portion of an upper surface of the first, second or third ohmic contact current spreading layer; And And a group III nitride semiconductor light emitting diode device having a flip chip structure comprising an n-type ohmic contact electrode and an electrode pad formed on a portion of an upper surface of a lower nitride-based clad layer of the light emitting structure for the light emitting diode device. The method of claim 1, The superlattice structure is a group III-nitride semiconductor light emitting diode device of a flip chip structure, characterized in that the two or three layers are a pair of periodically repeated multi-layer film. The method of claim 2, Each layer constituting the superlattice structure is a group 3 of flip chip structure, characterized by InN, InGaN, InAlN, AlGaN, GaN, AlInGaN, AlN, SiC, SiCN, MgN, ZnN, or SiN material having a thickness of 5 nm or less. Group nitride semiconductor light emitting diode device. The method of claim 3, Each group of the superlattice structure is a group III nitride semiconductor light emitting diode device of a flip chip structure, characterized in that the material doped with silicon (Si), magnesium (Mg), or zinc (Zn). The method of claim 1, The superlattice structure is a group III-nitride semiconductor having a flip chip structure, which can be replaced with an n-type conductive InGaN single layer or a p-type conductive InGaN single layer having a thickness of 5 nm or less. Light emitting diode device. The method of claim 1, And the first ohmic contact current spreading layer is formed of a group III nitride-based conductive thin film structure having a thickness of 6 nm or more. The method of claim 1, The group III nitride-based conductive thin film structure constituting the first ohmic contact current spreading layer is a material represented by the formula In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1). A group III nitride semiconductor light emitting diode device having a flip chip structure, characterized in that the film is a single layer or a multilayer film. The method of claim 1, The second ohmic contact current spreading layer is a group III-nitride group having a flip chip structure, which is formed of a transparent conductive thin film structure having a light transmittance of 50 Ω / □ or less while having a light transmittance of 70% or more in a wavelength band of 600 nm or less. Semiconductor light emitting diode device. The method of claim 1, The second group ohmic contact current spreading layer is a group III nitride semiconductor light emitting diode device of a flip chip structure, characterized in that consisting of a single layer (multi-layer) having a thickness of 5nm or more. The method of claim 1, The third ohmic contact current spreading layer is a group III nitride system of flip chip structure, which is formed of a reflective conductive thin film structure having a light reflectivity of 70% or more in a wavelength band of 600 nm or less and a sheet resistance of 50 Ω / □ or less. Semiconductor light emitting diode device. The method of claim 1, The group III-nitride semiconductor light emitting diode device of a flip chip structure, wherein the third ohmic contact current spreading layer is formed of a single layer or a multi-layer having a thickness of 200 nm or more. A growth substrate; A light emitting structure for a light emitting diode device comprising a lower nitride-based cladding layer made of an n-type conductive semiconductor material including a buffer layer formed on an upper surface of the growth substrate, a nitride-based active layer, and an upper nitride-based cladding layer made of a p-type conductive semiconductor material; ; A superlattice structure formed on a portion or the entire area of the upper nitride-based cladding layer of the light emitting structure for the light emitting diode device; A first ohmic contact current spreading layer formed on a portion or an entire region of the upper surface of the superlattice structure; A light extraction structure formed on a portion or an entire area of an upper surface of the first ohmic contact current spreading layer; A second ohmic contact current spreading layer formed on an upper surface of the light extraction structure; A third ohmic contact current spreading layer formed on an upper surface of the second ohmic contact current spreading layer; A p-type schottky contact electrode and an electrode pad formed on a portion of the upper surface of the light extracting structure, the first, second, or third ohmic contact current spreading layer; And And a group III nitride semiconductor light emitting diode device having a flip chip structure comprising an n-type ohmic contact electrode and an electrode pad formed on a portion of an upper surface of a lower nitride-based clad layer of the light emitting structure for the light emitting diode device. The method of claim 12, The superlattice structure is a group III-nitride semiconductor light emitting diode device of a flip chip structure, characterized in that the two or three layers are a pair of periodically repeated multi-layer film. The method of claim 12, Each layer constituting the superlattice structure is a group 3 of flip chip structure, characterized by InN, InGaN, InAlN, AlGaN, GaN, AlInGaN, AlN, SiC, SiCN, MgN, ZnN, or SiN material having a thickness of 5 nm or less. Group nitride semiconductor light emitting diode device. The method of claim 14, Each group of the superlattice structure is a group III nitride semiconductor light emitting diode device of a flip chip structure, characterized in that the material doped with silicon (Si), magnesium (Mg), or zinc (Zn). The method of claim 12, The superlattice structure is a group III-nitride semiconductor having a flip chip structure, which can be replaced with an n-type conductive InGaN single layer or a p-type conductive InGaN single layer having a thickness of 5 nm or less. Light emitting diode device. The method of claim 12, And the first ohmic contact current spreading layer is formed of a group III nitride-based conductive thin film structure having a thickness of 6 nm or more. The method of claim 12, The group III-nitride-based conductive thin film structure constituting the first ohmic contact current spreading layer is nitrided by In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1). A group III-nitride semiconductor light emitting diode device having a flip chip structure, characterized in that it is a single layer or a multilayer film of water. The method of claim 12, The second ohmic contact current spreading layer is a group III-nitride group having a flip chip structure, which is formed of a transparent conductive thin film structure having a light transmittance of 50 Ω / □ or less while having a light transmittance of 70% or more in a wavelength band of 600 nm or less. Semiconductor light emitting diode device. The method of claim 12, The second group ohmic contact current spreading layer is a group III nitride semiconductor light emitting diode device of a flip chip structure, characterized in that consisting of a single layer (multi-layer) having a thickness of 5nm or more. The method of claim 12, The third ohmic contact current spreading layer is a group III nitride system of flip chip structure, which is formed of a reflective conductive thin film structure having a light reflectivity of 70% or more in a wavelength band of 600 nm or less and a sheet resistance of 50 Ω / □ or less. Semiconductor light emitting diode device. The method of claim 12, The group III-nitride semiconductor light emitting diode device of a flip chip structure, wherein the third ohmic contact current spreading layer is formed of a single layer or a multi-layer having a thickness of 200 nm or more. The method of claim 12, The light extraction structure is a group III nitride semiconductor light emitting diode device of a flip chip structure, characterized in that the irregularities (texture) having a predetermined shape and dimensions are formed on the upper surface of the second ohmic contact current spreading layer. Preparing a growth substrate for growing a light emitting structure for a group III nitride semiconductor light emitting diode device; A lower nitride cladding layer made of an n-type conductive group III nitride semiconductor material on the upper surface of the growth substrate, a nitride active layer made of a group III nitride semiconductor material composed of a different composition, and a group 3 p-conductive conductivity; Forming a light emitting structure for a group III nitride semiconductor light emitting diode device in which an upper nitride cladding layer made of a nitride semiconductor material is sequentially stacked and grown; Forming a superlattice structure on an upper surface of a p-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) semiconductor, which is an upper nitride-based cladding layer of the light emitting structure for the light emitting diode device ; Forming a first ohmic contact current spreading layer on an upper surface of the superlattice structure; Forming a second ohmic contact current spreading layer on an upper surface of the first ohmic contact current spreading layer; Forming a third ohmic contact current spreading layer on an upper surface of the second ohmic contact current spreading layer; A portion of the first, second, and third ohmic contact current spreading layer, a superlattice structure, an upper nitride based cladding layer, a nitride based cladding layer, and a lower nitride based cladding layer is removed, and the lower nitride based cladding layer is removed. Exposing to air and forming an n-type ohmic contact electrode and an electrode pad on a portion of an upper surface of the lower nitride-based cladding layer; And Forming a p-type schottky contact electrode and an electrode pad on a portion of the upper surface of the first, second, or third ohmic contact current spreading layer; manufacturing a group III nitride semiconductor light emitting diode device having a flip chip structure Way. Preparing a growth substrate for growing a light emitting structure for a group III nitride semiconductor light emitting diode device; A lower nitride cladding layer made of an n-type conductive group III nitride semiconductor material on the upper surface of the growth substrate, a nitride active layer made of a group III nitride semiconductor material composed of a different composition, and a group 3 p-conductive conductivity; Forming a light emitting structure for a group III nitride semiconductor light emitting diode device in which an upper nitride cladding layer made of a nitride semiconductor material is sequentially stacked and grown; Forming a superlattice structure on an upper surface of a p-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) semiconductor, which is an upper nitride-based cladding layer of the light emitting structure for the light emitting diode device ; Forming a first ohmic contact current spreading layer on an upper surface of the superlattice structure; Forming a second ohmic contact current spreading layer on an upper surface of the first ohmic contact current spreading layer; A portion of the first and second ohmic contact current spreading layer, the superlattice structure, the upper nitride based cladding layer, the nitride based active layer, and the lower nitride based cladding layer was removed and the lower nitride based cladding layer was exposed to the atmosphere. Next, forming an n-type ohmic contact electrode and an electrode pad on a portion of the upper surface of the lower nitride-based cladding layer; Forming a third ohmic contact current spreading layer on an upper surface of the second ohmic contact current spreading layer; And Forming a p-type schottky contact electrode and an electrode pad on a portion of the upper surface of the first, second, or third ohmic contact current spreading layer; manufacturing a group III nitride semiconductor light emitting diode device having a flip chip structure Way. Preparing a growth substrate for growing a light emitting structure for a group III nitride semiconductor light emitting diode device; A lower nitride-based cladding layer made of an n-type conductive group III-nitride semiconductor material on the upper surface of the growth substrate, a nitride-based active layer made of a group III nitride-based semiconductor material composed of different compositions, and a group 3 of p-type conductivity Forming a light emitting structure for a group III nitride semiconductor light emitting diode device in which an upper nitride cladding layer made of a group nitride semiconductor material is sequentially stacked and grown; Forming a superlattice structure on an upper surface of a p-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) semiconductor, which is an upper nitride-based cladding layer of the light emitting structure for the light emitting diode device ; Forming a first ohmic contact current spreading layer on an upper surface of the superlattice structure; After removing a portion of the first ohmic contact current spreading layer, the superlattice structure, the upper nitride-based cladding layer, the nitride-based active layer, and the lower nitride-based cladding layer, the lower nitride-based cladding layer is exposed to the air. Forming an n-type ohmic contact electrode and an electrode pad on a portion of an upper surface of the lower nitride clad layer; Forming a second ohmic contact current spreading layer on an upper surface of the first ohmic contact current spreading layer; Forming a third ohmic contact current spreading layer on an upper surface of the second ohmic contact current spreading layer; And Forming a p-type schottky contact electrode and an electrode pad on a portion of the upper surface of the first, second, or third ohmic contact current spreading layer; manufacturing a group III nitride semiconductor light emitting diode device having a flip chip structure Way. The method of claim 24, And forming a light extraction structure by introducing surface irregularities on the upper surface of the first or second ohmic contact current spreading layer. The method of claim 25, And forming a light extraction structure by introducing surface irregularities on the upper surface of the first or second ohmic contact current spreading layer. The method of claim 26, And forming a light extraction structure by introducing surface irregularities on the upper surface of the first or second ohmic contact current spreading layer. The method of claim 24, The lower nitride based cladding layer, the nitride based active layer, the upper nitride based cladding layer, the superlattice structure, and the first ohmic contact current spreading layer are in-situ using MOCVD, MBE, or HVPE equipment. After the formation, the second and third ohmic contact current spreading layers are formed in an ex-situ state using an MOCVD, MBE, HVPE, sputter, evaporator, or PLD device. A method of manufacturing a group III nitride semiconductor light emitting diode device. The method of claim 25, The lower nitride based cladding layer, the nitride based active layer, the upper nitride based cladding layer, the superlattice structure, and the first ohmic contact current spreading layer are in-situ using MOCVD, MBE, or HVPE equipment. After the formation, the second and third ohmic contact current spreading layers are formed in an ex-situ state using an MOCVD, MBE, HVPE, sputter, evaporator, or PLD device. A method of manufacturing a group III nitride semiconductor light emitting diode device. The method of claim 26, The lower nitride based cladding layer, the nitride based active layer, the upper nitride based cladding layer, the superlattice structure, and the first ohmic contact current spreading layer are in-situ using MOCVD, MBE, or HVPE equipment. After the formation, the second and third ohmic contact current spreading layers are formed in an ex-situ state using an MOCVD, MBE, HVPE, sputter, evaporator, or PLD device. A method of manufacturing a group III nitride semiconductor light emitting diode device. The method of claim 24, The lower nitride-based cladding layer, the nitride-based active layer, the upper nitride-based cladding layer, and the superlattice structure are formed in-situ using MOCVD, MBE, or HVPE equipment, and then the first and second The second and third ohmic contact current spreading layer is a group III nitride of flip chip structure, which is formed in an ex-situ state by using MOCVD, MBE, HVPE, sputter, evaporator, or PLD equipment. Method for manufacturing a semiconductor semiconductor light emitting device. The method of claim 25, The lower nitride-based cladding layer, the nitride-based active layer, the upper nitride-based cladding layer, and the superlattice structure are formed in-situ using MOCVD, MBE, or HVPE equipment, and then the first and second The second and third ohmic contact current spreading layer is a group III nitride of flip chip structure, which is formed in an ex-situ state by using MOCVD, MBE, HVPE, sputter, evaporator, or PLD equipment. Method for manufacturing a semiconductor semiconductor light emitting device. The method of claim 26, The lower nitride-based cladding layer, the nitride-based active layer, the upper nitride-based cladding layer, and the superlattice structure are formed in-situ using MOCVD, MBE, or HVPE equipment, and then the first and second The second and third ohmic contact current spreading layer is a group III nitride of flip chip structure, which is formed in an ex-situ state by using MOCVD, MBE, HVPE, sputter, evaporator, or PLD equipment. Method for manufacturing a semiconductor semiconductor light emitting device. A growth substrate; A lower nitride cladding layer made of an n-type conductive group III-nitride semiconductor on the upper surface of the growth substrate, a nitride active layer made of another group III-nitride-based semiconductor material, and a group III nitride-based semiconductor of p-type conductivity A light emitting structure for a light emitting diode device composed of an upper nitride cladding layer; A superlattice structure formed on an upper surface of the light emitting structure for the light emitting diode device; A thin film structure for a group III nitride semiconductor light emitting diode device having a flip chip structure comprising a first ohmic contact current spreading layer formed on an upper surface of the superlattice structure. The method of claim 36, A thin film structure for a group III-nitride semiconductor light emitting diode device having a flip chip structure having a multilayer film formed by alternating a superlattice structure and a first ohmic contact current spreading layer on an upper surface of the light emitting structure for a light emitting diode device. The method of claim 36, The superlattice structure is a thin film structure for a group III-nitride semiconductor light emitting diode device having a flip chip structure, characterized in that two or three layers are a multi-layered film that is periodically repeated. The method of claim 36, Each layer constituting the superlattice structure is a group 3 of flip chip structure, characterized by InN, InGaN, InAlN, AlGaN, GaN, AlInGaN, AlN, SiC, SiCN, MgN, ZnN, or SiN material having a thickness of 5 nm or less. Thin film structure for group nitride semiconductor light emitting diode device. The method of claim 39, Each layer constituting the superlattice structure is a thin film structure for a group III nitride semiconductor light emitting diode device having a flip chip structure, characterized in that the material doped with silicon (Si), magnesium (Mg), or zinc (Zn). The method of claim 36, The superlattice structure is a group III-nitride semiconductor having a flip chip structure, which can be replaced with an n-type conductive InGaN single layer or a p-type conductive InGaN single layer having a thickness of 5 nm or less. Light emitting diode device. The method of claim 36, And the first ohmic contact current spreading layer is formed of a group III nitride-based conductive thin film structure. The method of claim 42, wherein The group III nitride-based conductive thin film structure constituting the first ohmic contact current spreading layer is 6 nm represented by the formula In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1). A thin film structure for a group III-nitride semiconductor light emitting diode device having a flip chip structure, which is characterized by being a single layer or a multilayer film of a nitride having the above thickness. The method of claim 36, The light emitting structure for the light emitting diode device, the superlattice structure, and the first ohmic contact spreading layer may be formed of a flip chip structure continuously formed in-situ using MOCVD, MBE, or HVPE growth equipment. Thin film structure for group III-nitride semiconductor light emitting diode device. The method of claim 36, The light emitting diode structure and the superlattice structure for the light emitting diode device are continuously formed in-situ using MOCVD, MBE, or HVPE growth equipment, and the ohmic contact current spreading layer is formed of the superlattice structure. A thin film structure for a group III-nitride semiconductor light emitting diode device having a flip chip structure formed in an ex-situ state using MOCVD, MBE, HVPE, sputter, or PLD growth equipment on an upper surface thereof.

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