KR102188498B1 - Nano structure semiconductor light emitting device - Google Patents

Abstract

The nanostructured semiconductor light emitting device according to an embodiment of the present invention includes a substrate having a non-emission area, a plurality of light-emitting areas, and at least one boundary area disposed between the plurality of light-emitting areas, and is disposed in the light-emitting area. 1 A nano core including a conductive type semiconductor, a plurality of nano light emitting structures including an active layer and a second conductive type semiconductor layer sequentially formed on the plurality of nano cores, and disposed in each of the plurality of light emitting regions The distances between the plurality of nano light-emitting structures are different from each other, and the width of each of the one or more border areas is a distance between the plurality of nano light-emitting structures included in each of the plurality of light-emitting areas adjacent to the border area, and the border area It is any one of an average value of distances between the plurality of nano light-emitting structures included in each of the plurality of light-emitting regions adjacent to.

Description

Nano structure semiconductor light emitting device{NANO STRUCTURE SEMICONDUCTOR LIGHT EMITTING DEVICE}

The present invention relates to a nanostructure semiconductor light emitting device.

A semiconductor light emitting device such as a light emitting diode (LED) is a device in which a material contained in the device emits light, and the energy generated by recombination of electrons and holes is converted into light and then emitted. These LEDs are currently widely used as lighting, display devices, and light sources, and their development is accelerating.

Recently, a semiconductor light emitting device using a nano structure and a manufacturing technology thereof have been proposed in order to increase light efficiency through improvement of crystallinity and an increase in a light emitting area. A semiconductor light emitting device using a nanostructure may not only generate relatively little heat, but also use an increased surface area of the nanostructure, thereby increasing a light emitting area to increase luminous efficiency.

In addition, since an active layer can be obtained on a non-polar or semi-polar surface, a decrease in efficiency due to polarization can be prevented, and droop characteristics can also be improved.

In the field of technology, light in a desired wavelength band can be stably output on a single substrate, and on the other hand, a nanostructure semiconductor light emission capable of realizing white light in one device by generating light in a plurality of wavelength bands on a single substrate. Devices are in demand.

A nanostructured semiconductor light emitting device according to an embodiment of the present invention includes: a substrate having a non-emission area, a plurality of emission areas, and at least one boundary area disposed between the plurality of emission areas; And a plurality of nano light emitting structures disposed in the light emitting region and including a nano core including a first conductivity type semiconductor, an active layer sequentially formed on the plurality of nano cores, and a second conductivity type semiconductor layer. And a distance between the plurality of nano light-emitting structures disposed in each of the plurality of light-emitting regions is different from each other, and a width of each of the one or more boundary regions is included in each of the plurality of light-emitting regions adjacent to the boundary region. It is any one of a distance between a plurality of nano light-emitting structures and an average value of a distance between the plurality of nano light-emitting structures included in each of the plurality of light-emitting areas adjacent to the boundary area.

The plurality of light-emitting areas may include: a first light-emitting area in which the plurality of nano light-emitting structures are spaced apart from each other by a first distance; A second light emitting region in which the plurality of nano light emitting structures are spaced apart from each other by a second distance different from the first distance; And a third light emitting region in which the plurality of nano light emitting structures are spaced apart from each other by a third distance different from the first distance and the second distance. It may include.

A plurality of nano light-emitting structures disposed in each of the first light-emitting region, the second light-emitting region, and the third light-emitting region generate light of different wavelengths, and light of the different wavelengths are combined with each other to provide white light can do.

The width of the boundary band may be determined as a value capable of minimizing the dispersion of distances between the plurality of nano light emitting structures included in each of the plurality of light emitting regions adjacent to the boundary region.

At least a portion of the plurality of light-emitting areas includes a first area and a second area, and the first area is adjacent to the non-emission area than the second area, and between a plurality of nano light-emitting structures disposed in the first area The distance of may be smaller than the distance between the plurality of nano light emitting structures disposed in the second region.

According to the present invention, it is possible to reduce the size distribution of the nano light-emitting structure in the entire light-emitting area by adjusting the distance between the nano light-emitting structures adjacent to the non-emitting area in the nanostructure semiconductor light emitting device. In addition, in a nanostructured semiconductor light emitting device having a plurality of light emitting regions that generate light in a plurality of wavelength bands, the boundary band width between the plurality of light emitting regions is set to minimize the dispersion of the gaps of the nano light emitting structures disposed in each light emitting region. By doing so, it is possible to effectively implement light of a desired wavelength.

Various and beneficial advantages and effects of the present invention are not limited to the above-described contents, and may be more easily understood in the course of describing specific embodiments of the present invention.

1 is a plan view showing a nanostructure semiconductor light emitting device according to an embodiment of the present invention.
FIG. 2 is an enlarged view showing regions A and B of the nanostructured semiconductor light emitting device illustrated in FIG. 1.
3 is an enlarged view showing region C of the nanostructured semiconductor light emitting device shown in FIG. 1.
4 is a cross-sectional view showing a nanostructure semiconductor light emitting device according to an embodiment of the present invention.
5 is a plan view showing a nanostructure semiconductor light emitting device according to an embodiment of the present invention.
6 is a cross-sectional view illustrating the nanostructured semiconductor light emitting device shown in FIG. 5.
7A to 7C are plan views provided to describe the nanostructured semiconductor light emitting device shown in FIG. 5.

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

Embodiments of the present invention may be modified into various other forms or various embodiments may be combined, and the scope of the present invention is not limited to the embodiments described below. In addition, embodiments of the present invention are provided in order to more completely explain the present invention to those having average knowledge in the art. Accordingly, the shapes and sizes of elements in the drawings may be exaggerated for clearer explanation, and elements indicated by the same reference numerals in the drawings are the same elements.

1 is a plan view showing a nanostructure semiconductor light emitting device according to an embodiment of the present invention.

Referring to FIG. 1, a nanostructure semiconductor light emitting device 100 according to an embodiment of the present invention may include a non-emission region 110 and a light emitting region 120 defined on a substrate. The non-emission area 110 may be defined as an area in which a plurality of nano light-emitting structures that emit light by receiving an electrical signal are not disposed. As shown in the embodiment of FIG. 1, the mesa around the light-emitting area 120 The region 111 and the first electrode 113 and the second electrode 115 may be included in the non-emission region 110. The first electrode 113 and the second electrode 115 are shown in FIG. 1 as having a pad portion and one or more finger portions extending from the pad portion, but are not necessarily limited to this shape.

Each of the first electrode 113 and the second electrode 115 may supply an electric signal so that a plurality of nano light emitting structures disposed in the light emitting region 110 emit light. For example, each of the plurality of nano light-emitting structures may include a nano core including a first conductivity type semiconductor, an active layer sequentially formed on the nano core, and a second conductivity type semiconductor layer, and the first electrode 111 ) May be electrically connected to the nano core, and the second electrode 113 may be electrically connected to the second conductivity type semiconductor layer.

Since the non-emission area 110 is located not only outside the light emitting area 120 of the nanostructured semiconductor light emitting device 100 but also inside the light emitting area 120, among a plurality of nano light emitting structures disposed in the light emitting area 120 Some may be adjacent to the non-emissive region 110. Among the plurality of nano light emitting structures, a nano core including a first conductivity type semiconductor may be formed by growing a first conductivity type semiconductor layer disposed to correspond to the light emitting region 120.

In this case, the nanocore grown in a region close to the non-emissive region 110 may have a higher growth rate than the nanocore grown in a region far from the non-emissive region 110. Accordingly, as the distance from the non-emission region 110 increases, the diameter of the nano light-emitting structure gradually decreases, and thus, the wavelength of light emitted from each of the nano light-emitting structures may be shortened. That is, the nano light-emitting structure close to the non-emissive region 110 has a relatively large diameter and thus can emit light of a relatively long wavelength, and the nano light-emitting structure far from the non-emissive region 110 has a relatively small diameter. As a result, it can emit light of a relatively short wavelength.

For example, in FIG. 1, the nano light-emitting structure disposed in the area A may be disposed closer to the mesa area, which is the non-emissive area 110 than the nano light-emitting structure disposed in the area B. As a method for forming a nano light-emitting structure, a peeling growth method in which a nitride semiconductor material, for example, GaN, is filled in a mask having a predetermined thickness or more to form a nano core may be applied. Accordingly, the rate at which GaN is filled may be different, and there may be a problem in that the diameter of the nanocore is not uniform. In addition, in a manufacturing method of forming a nanocore using a mask having a relatively thin thickness, not a peeling growth method, there may be a problem in that the diameters of the nanocores are formed differently as described above.

Accordingly, due to the above problems, the diameter of the nano light-emitting structure disposed in the area A may be larger than the diameter of the nano light-emitting structure disposed in the area B. Eventually, the wavelengths of light emitted from the nano light-emitting structures disposed in each of the A region and the B region may be different from each other, and-Region A generates relatively long-wavelength light-Accordingly, light of a desired wavelength is emitted from the entire emission region 120 It can be difficult to create.

For example, according to the distance from the non-luminescent area 110, the growth rate of the nano light-emitting structure disposed in the area A and the area B is different, and when a diameter deviation of the nano core occurs therefrom, the active layer of the nano light-emitting structure And the thickness of the second conductivity-type semiconductor layer may vary. In this case, in the nano light-emitting structure including a nano-core having a relatively large diameter, the active layer is formed thin, so that the composition ratio of indium (In) is reduced, and as a result, the wavelength of light emitted from the active layer is shortened, which is close to blue. Light can be emitted.

In an embodiment of the present invention, the plurality of nano light-emitting structures can emit light of even wavelength across the entire light-emitting area 120 by adjusting the spacing between the plurality of nano light-emitting structures included in the light-emitting area 120. have. For example, in the case of region A, where the growth rate of nanocores is relatively fast, by growing the nanocores more closely at shorter intervals than region B, the diameter difference between the nanocores arranged in the A region and the nanocores arranged in the B region Can be reduced.

When a plurality of nano cores are grown at regular intervals without adjusting the intervals as described above, the nano light-emitting structure disposed in the A region has a larger diameter than the nano light-emitting structure disposed in the B region, as well as the nano light emission disposed in the A region. The diameter scatter of each structure may be larger than the diameter scatter of the nano light-emitting structures disposed in the B region. Accordingly, the diameter distribution of the nano light-emitting structure may be increased throughout the light-emitting region 120, and it may be a problem in effectively implementing light having a desired wavelength. As mentioned above, in an embodiment of the present invention, the closer the nano light-emitting structure is to the non-light-emitting region 110, the shorter the distance between the nano light-emitting structure and the adjacent nano light-emitting structure, that is, more nano light-emitting structures within the same area. By arranging the nano light-emitting structure, it is possible to reduce the diameter dispersion of the nano light-emitting structure and efficiently generate light of a desired wavelength.

FIG. 2 is an enlarged view showing regions A and B of the nanostructured semiconductor light emitting device illustrated in FIG. 1.

Referring to FIG. 2, the nano light-emitting structure 120a included in the area A and the nano light-emitting structure 120b included in the area B may have the same diameter. However, the distance P1 between the nano light-emitting structures 120a included in the area A may be smaller than the distance P2 between the nano light-emitting structures 120b included in the area B.

As described above, region A is closer to the mesa region 111 included in the non-emissive region 110 than region B, and when the nanocores are collectively grown without any process condition control, A due to the difference in growth rate The nano light-emitting structure 120a included in the region has a larger diameter than the nano light-emitting structure 120b included in the B region. This may result in a difference in wavelength of light emitted by the nano light-emitting structure 120a included in the area A and the nano light-emitting structure 120b included in the area B, and thus, the nano light-emitting structure 120a included in the area A and By reducing the difference in diameter of the nano light emitting structure 120b included in the region B, light having a uniform wavelength may be obtained.

In an embodiment of the present invention, as shown in FIG. 2, intervals P1 and P2 between the nano light-emitting structures 120a and 120b may be differently set according to a distance away from the non-light-emitting region 110. The area A close to the non-luminescent area 110 may have a diameter larger than the nano light-emitting structure 120b of the area B due to the fast growth rate, and thus, between the nano light-emitting structures 120a in the area A The interval P1 may be set to be smaller than the interval P2 than the interval between the nano light emitting structures 120b in the region B. When P1 is less than P2, the density of the nano light-emitting structure 120a in the area A is greater than the density of the nano light-emitting structure 120b in the area B, and the difference in diameter between the nano light-emitting structures 120a and 120b can be minimized therefrom. have.

The diameter distribution of the nano light-emitting structures 120a and 120b throughout the light-emitting area 120 is determined by setting the intervals P1 and P2 differently between the nano light-emitting structures 120a and 120b according to the distance away from the non-light-emitting area 110. Can be reduced. As described above, the difference in diameter of the nano light-emitting structures 120a and 120b may lead to a difference in wavelength of light emitted by the nano light-emitting structures 120a and 120b, so that the diameter distribution of the nano light-emitting structures 120a and 120b By reducing it, light of a desired wavelength can be realized.

3 is an enlarged view showing region C of the nanostructured semiconductor light emitting device shown in FIG. 1.

Referring to FIG. 3, the region C may include first and second regions C1 and C2 included in the light emitting region 120 and a partial region of the second electrode 115 of the non-emitting region 110. have. Since the second electrode 115 is a region included in the non-emissive region 110, the nano light-emitting structure does not grow, and a plurality of nano light-emitting structures may be disposed in the first region C1 and the second region C2. have. As described above, the nano light-emitting structure may include a nano core including a first conductivity type semiconductor, an active layer formed on the nano core in order, and a second conductivity type semiconductor layer.

Referring to FIG. 3, the first and second regions C1 and C2 included in region C are light emitting regions, and a plurality of nano light emitting structures are disposed. At this time, since the first region C1 is disposed closer to the second electrode 115, which is the non-emissive region 110, compared to the second region C2, the nano light-emitting structure disposed in the first region C1 The growth rate may be faster than the growth rate of the nano light emitting structure disposed in the second region C2. Therefore, in order to minimize the diameter deviation of the nano light-emitting structure due to the difference in the growth rate of the nano light-emitting structure disposed in the first area C1 and the growth rate of the nano light-emitting structure disposed in the second area C2, the first area ( The spacing between the nano light-emitting structures disposed in C1) may be set to be narrower than the spacing between the nano light-emitting structures disposed in the second region C2.

The spacing between the nano light-emitting structures disposed in the first area C1 may be determined by at least one of a spacing between the nano light-emitting structures disposed in the second area C2 and the area of the non-emissive area 110 . In an embodiment, the spacing between the nano light-emitting structures disposed in the first region C1 may be determined as a value obtained by multiplying the spacing between the nano light-emitting structures disposed in the second region C2 by a predetermined compensation factor α. . In this case, the compensation coefficient α may be a value determined by the wavelength of light to be generated in the nanostructured semiconductor light emitting device, the area of the non-emission area 110, and the area of the emission area 120.

The first region C1 is a region adjacent to the second electrode 115 that is the non-emissive region 110 than the second region C2, and a partial region adjacent to the non-emission region 110 over the entire luminescent region 120 In the first region C1, a region having a narrow gap between the nano light emitting structures may be set. At this time, the width d of the first region C1 is the wavelength of light to be generated in the nanostructured semiconductor light emitting device, the gap between the nano light emitting structures disposed in the second region C2, and the non-light emitting region, similar to the compensation factor α. It may be a value determined by the area of (110) and the area of the light emitting area 120.

In an embodiment, when the interval between the nano light-emitting structures in the second region C2 is 2.8 μm, the compensation factor α may be 0.9, and the width d of the first region C1 may be 6 μm. That is, the interval between the nano light emitting structures disposed in the first region C1 may be 2.5 μm. When forming the nano light-emitting structure at the same interval without setting the compensation factor α and the first area C1, the diameter and the non-light-emitting area of the nano light-emitting structure adjacent to the boundary between the non-emitting area 110 and the light-emitting area 120 The diameter of the nano light-emitting structure formed in a region 40 μm away from the boundary between (110) and the light-emitting region 120 may differ by about 150 nm or more. This may appear as a difference of about 20 nm or more in the emission wavelength. By appropriately setting the compensation coefficient α and the width d of the first region C1, light of a desired wavelength can be uniformly generated.

In this case, the width d of the first region C1 may be set to 15% or less compared to any one of the long axis and the short axis length of the light emitting area 120. When the width d of the first region C1 is set too large, the diameter of the nano light emitting structure disposed adjacent to the boundary between the first region C1 and the second region C2 is rather than in the second region C2. It may be smaller than the diameter of the disposed nano light emitting structure. Accordingly, since a nano light emitting structure that generates light of a shorter wavelength than that of a desired wavelength may be formed in the first region C1 adjacent to the boundary with the second region C2, the width d of the first region C1 May be set to 15% or less compared to any one of the long axis and the minor axis length of the light emitting area 120.

4 is a cross-sectional view showing a region C of the nanostructured semiconductor light emitting device shown in FIG. 1.

Referring to FIG. 4, a nano light emitting structure is not formed on the second electrode 115 included in the non-emissive region 110, and only the first and second regions C1 and C2 included in the light emitting region 120 Nano light emitting structures 240 and 250 may be formed. As shown in FIG. 4, the nanostructure semiconductor light emitting device 100 includes a substrate 210, a base layer 220 provided on the substrate 210, an insulating film 230 provided on the base layer 220, and a base. A plurality of nano light emitting structures 240 and 250 formed on the layer 220 may be included.

The base layer 220 may be formed on the substrate 210. The base layer 220 not only provides a growth surface of the nano light-emitting structures 240 and 250, but also serves to electrically connect the polarities of one side of the plurality of nano light-emitting structures 240 and 250.

The substrate 210 may be an insulating, conductive, or semiconductor substrate. For example, the substrate 210 may be sapphire, SiC, Si, MgAl ₂ O ₄ , MgO, LiAlO ₂ , LiGaO ₂ , or GaN. The base layer 220 may be a nitride semiconductor satisfying Al _x In _y Ga _{1 -x- y} N (0≤x≤1, 0≤y≤1, 0≤x+y≤1), and a specific conductivity It may be doped with n-type impurities such as Si to have a type.

The insulating layer 230 may be provided on the base layer 220 to provide a plurality of openings O through which a plurality of nano light emitting structures 240 and 250 may be formed. The insulating layer 230 may be a type of mask layer having a plurality of openings O. Nano cores 241 and 251 may be formed by disposing the insulating layer 230 having a plurality of openings O on the base layer 220 and growing the base layer 220 through the plurality of openings O. . The nano cores 241 and 251 may include a first conductivity type semiconductor, for example, the first conductivity type semiconductor may include n-type GaN. The side surfaces of the nanocores 241 and 251 may be non-polar m-planes. Meanwhile, the insulating layer 230 may include silicon oxide or silicon silicon nitride moles as an insulating material. For example, the insulating layer 230 may include a material such as SiO ₂ , SiN, TiO ₂ , Si ₃ N ₄ , Al ₂ O ₃ , TiN, AlN, ZrO ₂ , TiAlN, TiSiN, and the like.

Active layers 242 and 252 and second conductivity-type semiconductor layers 243 and 253 may be sequentially formed on the nano cores 241 and 251. The active layers 242 and 252 have a multi-quantum well (MQW) structure in which a quantum well layer and a quantum barrier layer are alternately stacked with each other, for example, in the case of a nitride semiconductor, a GaN/InGaN structure may be used. SQW) structure could also be used. The second conductivity-type semiconductor layers 243 and 253 may be _crystals that satisfy p-type Al _x In _y Ga _{1 -x- y} N.

The active layers 242 and 252 may be formed to cover side surfaces and upper surfaces of the nano cores 241 and 251. In this embodiment, the active layers 242 and 252 may be formed on the surfaces of each of the nano cores 241 and 251 by a batch process. At this time, when the nano-cores 241 and 251 have different diameters, the active layers 242 and 252 having different compositions may be provided under the same conditions due to differences in lattice constants, specific surface areas, and strains, and each nano light emission therefrom The wavelength of light generated by the structures 240 and 250 may vary. Specifically, when the quantum well layer constituting the active layer is In _x Ga _{1 - x} N (0≦ _x ≦1), the indium (In) content may vary according to nano cores having different diameters. As a result, the wavelength of light emitted from each quantum well layer may vary.

That is, the diameter distribution of the nano cores 241 and 251 may be minimized within the light emitting area 120 in order to implement light having a desired wavelength in the nanostructured semiconductor light emitting device 100. However, as described above, since the diameter of the nano light-emitting structures 240 and 250 increases as they are closer to the non-light-emitting region 110, in the present invention, the diameter distribution is minimized by adjusting the distance between the nano light-emitting structures 240 and 250. can do.

Referring to FIG. 4, the distance between the first nano light emitting structures 240 disposed in the first region C1 adjacent to the second electrode 115 which is the non-emitting region 110 is d1, and the second region C2 The interval between the second nano light emitting structures 250 disposed in) may be set to d2. d1 is a value smaller than d2, and the first nano light-emitting structure 240 in the first region C1 may be disposed at a higher density than the second nano light-emitting structure 250 in the second region C2. Therefore, the width of the nano cores 241 and 251 included in each of the first and second nano light-emitting structures 240 and 250 is w, despite the difference in growth rate between the first region C1 and the second region C2. Can have almost the same value as.

Meanwhile, the second conductivity type semiconductor layers 243 and 253 may further include an electron blocking layer (not shown) adjacent to the active layers 242 and 252. The electron blocking layer may have a structure in which a plurality of different compositions of n-type Al _x In _y Ga _{1 -x- y} N are stacked or one or more layers composed of Al _y Ga _(1-y) N, and an active layer ( Since the band gap is larger than those of 242 and 252, it is possible to prevent electrons from passing to the second conductivity type semiconductor layers 243 and 253.

The second conductivity-type semiconductor layers 243 and 253 may include GaN doped with p-type impurities, unlike the nanocores 241 and 251 including the first conductivity-type semiconductor. Si is well known as an n-type impurity included as a doping material in the nanocores 241 and 251, and as p-type impurities applied to the second conductivity-type semiconductor layers 243 and 253, Zn, Cd, Be, Mg, There are Ca and Ba, and mainly Mg and Zn can be used.

5 is a plan view showing a nanostructure semiconductor light emitting device according to an embodiment of the present invention.

Referring to FIG. 5, a nanostructured semiconductor light emitting device 300 according to an embodiment of the present invention may be divided into a non-emission area 310 and a light emission area 320. In particular, like the nanostructured semiconductor light emitting device 300 shown in FIG. 1, the non-emission region 310 includes a mesa region 311 around the light emitting region 320, a first electrode 313 and a second electrode ( 315) may be included.

Referring to FIG. 5, the emission region 320 may be divided into a plurality of emission regions 320A, 320B, and 320C, and each of the emission regions 320A, 320B, and 320C may generate light having different wavelengths. . For example, the first emission area 320A may generate light of a first wavelength, the second emission area 320B may generate light of a second wavelength different from the first wavelength, and the third emission area ( 320C) may generate light of a third wavelength different from the first and second wavelengths. In particular, light of the first, second, and third wavelengths may be mixed with each other to provide white light. In this case, a single nanostructure semiconductor light emitting device 300 may output white light.

In the embodiment shown in FIG. 5, the first, second, and third light-emitting areas 320A, 320B, and 320C may each generate light of different wavelengths. 320B, 320C) may be intentionally set differently between the nano light-emitting structures disposed on each of them. For example, the distance between the nano light-emitting structures disposed in each of the first, second, and third light-emitting regions 320A, 320B, and 320C may be set to differ from each other by at least 200 nm, and under the same conditions, the nanostructures The semiconductor light emitting device 300 may output white light.

A first boundary region 330A and a second boundary region 330B may be disposed between the first, second, and third emission regions 320A, 320B, and 320C, respectively. Each of the first and second boundary regions 330A and 330B may have different widths, and in this case, the widths of the boundary regions 330A and 330B are light emitting regions 320A and 320B adjacent to the boundary regions 330A and 330B. , 320C) may be set to a value capable of minimizing the spacing scattering degree of the nano light-emitting structures included in).

For example, the width of the first boundary region 330A may be set to a value capable of minimizing the spacing distribution of nano light-emitting structures disposed in each of the first and second light-emitting regions 320A and 320B. have. In this case, the width of the first border area 330A may affect the border of the first emission area 320A and the border of the second emission area 320B, from which the first and second emission areas 320A, This is because the spacing distribution of the nano light-emitting structures disposed at 320B) may vary. This will be described later with reference to FIGS. 7A to 7C.

6 is a cross-sectional view illustrating the nanostructured semiconductor light emitting device shown in FIG. 5.

Referring to FIG. 6, the nanostructure semiconductor light emitting device 300 includes a substrate 410, a base layer 420 provided on the substrate 410, an insulating film 430 provided on the base layer 420, and a base layer. A plurality of nano light emitting structures 440, 450, and 460 formed on the 420 may be included. The light-emitting area 340 may be divided into first, second, and third light-emitting areas 340A, 340B, and 340C. Each of the first, second, and third light-emitting areas 340A, 340B, and 340C Nano light-emitting structures 440, 450, and 460 may be disposed.

The base layer 420 may be formed on the substrate 410. The base layer 420 not only provides a growth surface of the nano light emitting structures 440, 450, and 460, but may also serve to electrically connect the polarities of one side of the plurality of nano light emitting structures 440, 450, and 460. .

The substrate 410 may be an insulating, conductive, or semiconductor substrate. For example, the substrate 410 may be sapphire, SiC, Si, MgAl ₂ O ₄ , MgO, LiAlO ₂ , LiGaO ₂ , or GaN. The base layer 420 may be a nitride semiconductor satisfying Al _x In _y Ga _{1 -x- y} N (0≤x≤1, 0≤y≤1, 0≤x+y≤1), and a specific conductivity type It may be doped with n-type impurities such as Si to have.

The insulating layer 430 may be provided on the base layer 420 to provide a plurality of openings O through which a plurality of nano light emitting structures 440, 450, and 460 may be formed. The insulating layer 430 may be a type of mask layer having a plurality of openings O. Nano cores 441, 451, and 461 are formed by disposing an insulating film 430 having a plurality of openings (O) on the base layer 420 and growing the base layer 420 through the plurality of openings (O). I can. The nanocores 441, 451, and 461 may include a first conductivity type semiconductor, for example, the first conductivity type semiconductor may include n-type GaN. The side surfaces of the nano cores 441, 451, and 461 may be non-polar m-planes. Meanwhile, the insulating layer 430 may include silicon oxide or silicon silicon nitride mole as an insulating material. For example, the insulating layer 230 may include a material such as SiO ₂ , SiN, TiO ₂ , Si ₃ N ₄ , Al ₂ O ₃ , TiN, AlN, ZrO ₂ , TiAlN, TiSiN, and the like.

Active layers 442, 452, 462 and second conductivity type semiconductor layers 443, 453, 463 may be sequentially formed on the nano cores 441, 451, 461. The active layers 442, 452, 462 may have a multiple quantum well (MQW) structure in which a quantum well layer and a quantum barrier layer are alternately stacked, for example, in the case of a nitride semiconductor, a GaN/InGaN structure may be used. A well (SQW) structure could also be used. The second conductivity-type semiconductor layers 443, 453, and 463 may be crystals that satisfy p-type Al _x In _y Ga _1-xy N.

The active layers 442, 452, and 462 may be formed to cover side surfaces and upper surfaces of the nano cores 441, 451, and 461. In this embodiment, the active layers 442, 452, and 462 may be formed on the surfaces of each of the nano cores 441, 451, and 461 by a batch process. At this time, when the nanocores 441, 451, and 461 have different heights or diameters, active layers 442, 452, 462 having different compositions under the same conditions may be provided due to differences in lattice constants, specific surface areas, and strains In addition, the wavelength of light generated by each of the nano light emitting structures 440, 450, and 460 may be changed therefrom. Specifically, when the composition of the quantum well layer constituting the active layers 442, 452, 462 is In _x Ga _{1 - x} N (0 _{≤ x ≤} 1), indium ( In) content may vary. As a result, the wavelength of light emitted from each quantum well layer may vary.

In the embodiment shown in FIG. 6, the first, second, and third light-emitting areas 340A, 340B, and 340C are included in each of the light-emitting areas 340A, 340B, and 340C to generate light of different wavelengths. The interval between the nano light emitting structures 440, 450, and 460 may be set differently. In FIG. 6, the distance d1 between the first nano light emitting structures 440 is the largest, the distance d3 between the third nano light emitting structures 460 is the smallest, and the distance d2 between the second nano light emitting structures 450 is d3. Although it is illustrated as being larger than and smaller than d1, it goes without saying that the nano light emitting structures 440, 450, and 460 may be provided in a different form.

In one embodiment, the distance d1 between the first nano light-emitting structures 440 may be 1600 to 2300 nm, the distance d2 between the second nano light-emitting structures 450 may be 1200 to 1600 nm, and the third nano light-emitting structure The interval d3 between the 460 may be 1000 ~ 1200nm. By setting d1, d2, d3 in the numerical range as described above, and forming the nano light emitting structures 440, 450, 460 so that the difference between d1, d2, and d3 is at least 200 nm or more, one nanostructure semiconductor light emitting device ( 300) can provide white light. On the other hand, the width w and height h of the nano cores 441, 451, and 461 included in the first, second, and third nano light emitting structures 440, 450, and 460 have been exemplified as having substantially the same value. Alternatively, the wavelength of light generated by each of the nano light emitting structures 440, 450, 460 may be changed by adjusting the width and height of the nano cores 441, 451, and 461. For example, as the gap between the nanocores 441, 451, and 461 increases or the diameter of each nanocore 441, 451, and 461 decreases, the active layer included in the nano light emitting structures 440, 450, 460 ( As the thickness of the 442, 452, and 462 increases, the composition ratio of indium (In) increases, and the wavelength of light emitted by each of the nano light-emitting structures 440, 450, 460 may increase therefrom. On the other hand, in terms of the height of the nano cores 441, 451, 461, the lower the height of the nano cores 441, 451, 461, the thicker the active layers 442, 452, 462, and thus the active layers 442, 452, 462 ) May increase the composition ratio of indium (In). Therefore, the lower the height of the nano cores 441, 451, 461, the longer the wavelength of light emitted by the nano light emitting structures 440, 450, 460, and conversely, the height of the nano cores 441, 451, 461 As is higher, the wavelength of light emitted by the nano light emitting structures 440, 450, and 460 may be shorter.

Meanwhile, the second conductivity-type semiconductor layers 443, 453, and 463 may further include an electron blocking layer (not shown) adjacent to the active layers 442, 452, and 462. The electron blocking layer may have a structure in which a plurality of different compositions of n-type Al _x In _y Ga _{1 -x- y} N are stacked or one or more layers composed of Al _y Ga _(1-y) N, and an active layer ( Since the band gap is larger than those of 442, 452, and 462, it is possible to prevent electrons from passing to the second conductivity type semiconductor layers 443, 453, and 463.

The second conductivity-type semiconductor layers 443, 453, and 463 may include GaN doped with p-type impurities, unlike the nanocores 441, 451, and 461 including the first conductivity-type semiconductor. Si is well known as an n-type impurity included as a doping material in the nanocores 441, 451, and 461, and as p-type impurities applied to the second conductivity-type semiconductor layers 443, 453, 463, Zn, Cd, There are Be, Mg, Ca, Ba, etc., mainly Mg, Zn can be used.

7A to 7C are plan views provided to describe the nanostructured semiconductor light emitting device shown in FIG. 5.

7A to 7C are a method of setting the width L of the first boundary area 330A defined between the first emission area 320A and the second emission area 320B in the nanostructure semiconductor light emitting device shown in FIG. 5. It is a diagram provided to illustrate. 7A to 7C all show the first light emitting area 320A, the second light emitting area 320B, and the first boundary area 330A disposed therebetween, but are described with reference to FIGS. 7A to 7C. An exemplary embodiment of the present invention may also be applied to the second emission area 320B, the third emission area 320C, and the second boundary area 330B disposed therebetween.

First, referring to FIG. 7A, a plurality of nano light emitting structures 440 and 450 having substantially the same diameter may be disposed in the first and second light emitting regions 320A and 320B, respectively. The first nano light-emitting structure 440 disposed in the first light-emitting area 320A may be disposed at a relatively narrower interval compared to the second nano light-emitting structure 450 disposed in the second light-emitting area 320B. That is, the distance d1 between the first nano light-emitting structures 440 may be smaller than the distance d2 between the second nano light-emitting structures 450.

In the embodiment of FIG. 7A, the width L of the first boundary area 330A may have the same value as the distance d1 between the first nano light-emitting structures 440 disposed in the first emission area 320A. Therefore, the effect of the first boundary region 330A on the first emission region 320A may be very insignificant, but the distance d2 between the second nano light emitting structures 450 included in the second emission region 320B is large. It may have an effect, and the scattering degree of the distance d2 between the second nano light-emitting structures 450 in the second light-emitting region 320 may increase.

Next, referring to FIG. 7B, the width L of the first boundary area 330A may have a value equal to the distance d2 between the second nano light emitting structures 450 disposed in the second emission area 320B. Accordingly, contrary to the embodiment of FIG. 7A, the influence of the first boundary region 330A on the second emission region 320B can be reduced, but the first nano light emitting structure 440 included in the first emission region 320A ), the scatter of the interval d1 may increase.

Finally, referring to FIG. 7C, the width L of the first boundary region 330A is set as the average value of the distance d1 between the first nano light emitting structures 440 and the distance d2 between the second nano light emitting structures 450 Can be. Accordingly, contrary to the embodiments of FIGS. 7A and 7B, the first boundary area 330A includes the first and second nano light emitting structures 440 included in the first and second light emitting areas 320A and 320B, respectively. , 450) can affect both the intervals d1 and d2.

However, rather than an increase in the scatter of the spacing d2 between the second nano light-emitting structures 450 that may occur in the embodiment of FIG. 7A, the spacing d2 between the second nano light-emitting structures 450 that may occur in the embodiment of FIG. 7C The increase in scatter can be smaller. Likewise, rather than an increase in the scatter of the spacing d1 between the first nano light emitting structures 440 that may occur in the embodiment of FIG. 7B, the spacing d1 between the first nano light emitting structures 440 that may occur in the embodiment of FIG. 7C The increase in scatter can be smaller.

That is, as described in the embodiment of FIGS. 7A to 7C, the first and second nano light emitting structures 440 disposed in the light emitting regions 320A and 320B adjacent to the left and right by the width L of the first boundary region 330A. , 450), the scattering of the intervals d1 and d2 may increase. Increasing the scattering of the distances d1 and d2 between the nano light-emitting structures 440 and 450 may affect the wavelength of light emitted from the first and second light-emitting regions 320A and 320B, so that the nanostructure semiconductor light-emitting device ( The width of the first boundary area 330A may be set in consideration of the wavelength of light to be obtained from 300). In a similar manner, the width of the second boundary area 330B disposed in the second and third light emitting areas 320B and 320C may be set.

The present invention is not limited by the above-described embodiments and the accompanying drawings, but is intended to be limited by the appended claims. Therefore, various types of substitutions, modifications and changes will be possible by those of ordinary skill in the art within the scope not departing from the technical spirit of the present invention described in the claims, and this also belongs to the scope of the present invention. something to do.

100, 300: nanostructure semiconductor light emitting device
110, 310: non-luminous area
120, 320: light emitting area
210, 410: substrate
220, 420: base layer
230, 430: insulating film
240, 250, 440, 450, 460: nano light emitting structure
241, 251, 441, 451, 461: nano core
242, 252, 442, 452, 462: active layer
243, 253, 443, 453, 463: second conductivity type semiconductor layer

Claims (5)

A substrate having a non-emission area, a plurality of emission areas, and at least one boundary area disposed between the plurality of emission areas; And
A plurality of nano light-emitting structures disposed in the emission region and including a nano core including a first conductivity type semiconductor, an active layer sequentially formed on the plurality of nano cores, and a second conductivity type semiconductor layer; Including,
A distance between the plurality of nano light-emitting structures disposed in a first light-emitting area among the plurality of light-emitting areas and a distance between the plurality of nano light-emitting structures disposed in a second light-emitting area different from the first light-emitting area are different from each other,
The width of each of the at least one boundary region is a distance between each of the plurality of nano light emitting structures included in one of the plurality of light emitting regions adjacent to the boundary region, and the plurality of light emitting regions adjacent to the boundary region A nanostructure semiconductor light emitting device having any one of an average value of distances between each of the plurality of nano light emitting structures included in the other light emitting region.
The method of claim 1,
The plurality of light-emitting areas further include a third light-emitting area different from the first light-emitting area and the second light-emitting area,
The plurality of nano light-emitting structures are disposed to be spaced apart from each other by a first distance in the first light-emitting region,
In the second light-emitting region, the plurality of nano light-emitting structures are disposed to be spaced apart from each other by a second distance different from the first distance,
In the third light emitting region, the plurality of nano light emitting structures are disposed to be spaced apart from each other by a third distance different from the first distance and the second distance.
The method of claim 2,
A plurality of nano light-emitting structures disposed in each of the first light-emitting region, the second light-emitting region, and the third light-emitting region generate light of different wavelengths, and light of the different wavelengths are combined with each other to provide white light Nano structure semiconductor light emitting device.
The method of claim 1,
The width of the boundary region is determined to be a value capable of minimizing a dispersion of distances between the plurality of nano light emitting structures included in each of the plurality of light emitting regions adjacent to the boundary region.
The method of claim 1,
At least a portion of the plurality of light-emitting regions includes a first region and a second region, and the first region is adjacent to the non-emission region than the second region,
A nanostructure semiconductor light emitting device in which a distance between the plurality of nano light emitting structures disposed in the first region is smaller than a distance between the plurality of nano light emitting structures disposed in the second region.

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