KR20180001009A - Semiconductor device and light emitting device package having thereof - Google Patents

Abstract

An embodiment of the present invention relates to a semiconductor device and a light emitting device package having the same. The semiconductor device according to an embodiment of the present invention comprises: a first conductive type semiconductor layer; an active layer formed on the first conductive type semiconductor layer; an electron blocking layer (EBL) formed on the active layer; a second conductive type first semiconductor layer arranged on the EBL and including AlGaN; a second conductive type second semiconductor layer formed on the second conductive type first semiconductor layer; and a second conductive type third semiconductor layer formed on the second conductive type second semiconductor layer, wherein a boundary surface between the second conductive type second semiconductor layer and the second conductive type third semiconductor layer may have surface roughness (root mean square (RMS)) greater than the second conductive type third semiconductor layer. An embodiment of the present invention improves potential and a defect to enhance light emitting efficiency.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a semiconductor device and a light emitting device package having the same,

Embodiments relate to semiconductor devices.

An embodiment relates to a light emitting device package.

An embodiment relates to a lighting device.

Semiconductor devices including compounds such as GaN and AlGaN have many merits such as wide and easy bandgap energy, and can be used variously as light emitting devices, light receiving devices, and various diodes.

Particularly, a light emitting device such as a light emitting diode or a laser diode using a semiconductor material of Group 3-5 or 2-6 group semiconductors can be applied to various devices such as a red, Blue, and ultraviolet rays. By using fluorescent materials or combining colors, it is possible to realize a white light beam with high efficiency. Also, compared to conventional light sources such as fluorescent lamps and incandescent lamps, low power consumption, , Safety, and environmental friendliness.

In addition, when a light-receiving element such as a photodetector or a solar cell is manufactured using a semiconductor material of Group 3-5 or Group 2-6 compound semiconductor, development of a device material absorbs light of various wavelength regions to generate a photocurrent , It is possible to use light in various wavelength ranges from the gamma ray to the radio wave region. It also has advantages of fast response speed, safety, environmental friendliness and easy control of device materials, so it can be easily used for power control or microwave circuit or communication module.

Accordingly, the semiconductor device can be replaced with a transmission module of an optical communication means, a light emitting diode backlight replacing a cold cathode fluorescent lamp (CCFL) constituting a backlight of an LCD (Liquid Crystal Display) display device, White light emitting diodes (LEDs), automotive headlights, traffic lights, and gas and fire sensors. In addition, semiconductor devices can be applied to high frequency application circuits, other power control devices, and communication modules.

A typical semiconductor device can be strained to a semiconductor layer by a difference in lattice mismatch and thermal expansion coefficient between respective semiconductor layers. The strain change may cause dislocations or defects in the semiconductor layer. The potential or defect may cause V-pits or cracks, and V-pits or cracks may cause leakage currents.

Embodiments can provide a semiconductor device capable of improving crystallinity and a light emitting device package having the semiconductor device.

Embodiments can provide a semiconductor device capable of improving the luminous efficiency and a light emitting device package having the same.

Embodiments can provide a semiconductor device which improves back diffusion of p dopant to improve light extraction efficiency and a light emitting device package having the same.

Embodiments can provide a semiconductor device that improves dislocations and defects to improve electrical characteristics due to leakage current, and a light emitting device package having the semiconductor device.

The first embodiment includes a first conductive semiconductor layer, an active layer on the first conductive semiconductor layer, an electron blocking layer (EBL) on the active layer, and a second conductive type semiconductor layer disposed on the EBL and containing AlGaN A second conductive type second semiconductor layer on the second conductive type first semiconductor layer and a second conductive type third semiconductor layer on the second conductive type second semiconductor layer, Layer and the second conductive type third semiconductor layer may have a root mean square (RMS) of the surface of the second conductive type third semiconductor layer. The embodiment can improve the luminous efficiency by improving the potential and the defects.

An embodiment of the present invention provides a light emitting device including a substrate, a first conductive semiconductor layer, an active layer on the first conductive semiconductor layer, Growing an EBL on the active layer and a first conductive semiconductor layer on the EBL; Growing a second conductive type second semiconductor layer on the second conductive type first semiconductor layer in a 3D (three dimensional) mode; And growing the second conductive type third semiconductor layer on the second conductive type second semiconductor layer in a 2D (2D) mode, thereby improving the light emitting efficiency by improving dislocations and defects.

Embodiments can improve the crystallinity by bending the potential from the second conductive type first semiconductor layer by the second conductive type second semiconductor layer grown in the 3D mode on the second conductive type first semiconductor layer.

Embodiments can improve the emission efficiency by reducing TDD (Threading dislocation Density) of the final semiconductor layer by improving the propagation of potential.

The embodiment improves the back diffusion of the p dopant from the EBL to the active layer by maintaining the doping concentration of the second conductivity type dopant of the second conductivity type semiconductor layer constant, thereby improving the light extraction efficiency have.

The embodiment can improve dislocations and defects to improve electrical characteristics due to leakage currents.

Embodiments can improve dislocations and defects to realize fully TE polarized light of an ultraviolet light emitting device.

1 is a cross-sectional view showing a semiconductor device according to an embodiment.
2 is a cross-sectional view of a semiconductor device showing region A of FIG.
FIG. 3 is a diagram showing the dopant concentration of the second conductive type second semiconductor layer and the second conductive type third semiconductor layer analyzed by SIMS (secondary-ion mass spectroscopy).
4 and 5 are graphs comparing RSM data of the comparative example and the embodiment.
6 is a view showing the surface of the second conductivity type third semiconductor layer of the embodiment.
7 to 10 are cross-sectional views showing a method of manufacturing a semiconductor device of the embodiment.
11 is a cross-sectional view illustrating a light emitting device package according to an embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects, features and advantages of the present invention will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: FIG.

In the description of the embodiment according to the present invention, in the case of being described as being formed "on or under" of each element, the upper (upper) or lower (lower) or under are all such that two elements are in direct contact with each other or one or more other elements are indirectly formed between the two elements. Also, when expressed as "on or under", it may include not only an upward direction but also a downward direction with respect to one element.

The semiconductor device may include various electronic devices such as a light emitting device and a light receiving device. The light emitting device and the light receiving device may include the first conductivity type semiconductor layer, the active layer, and the second conductivity type semiconductor layer.

The semiconductor device according to this embodiment may be a light emitting device.

The light emitting device emits light by recombination of electrons and holes, and the wavelength of the light is determined by the energy band gap inherent to the material. Thus, the light emitted may vary depending on the composition of the material.

2 is a cross-sectional view of a semiconductor device showing region A of FIG. 1, and FIG. 3 is a cross-sectional view of a semiconductor device according to a second embodiment of the present invention, Layer dopant concentration by SIMS (Secondary-ion mass spectroscopy). FIGS. 4 and 5 are graphs comparing RSM data of the comparative example and the embodiment.

As shown in FIGS. 1 and 2, the semiconductor device of the embodiment can improve the crystallinity by improving the dislocation of the semiconductor layer. The semiconductor device of the embodiment improves the dislocation due to the difference in lattice constant between the semiconductor layers, and uniformly maintains the dopant concentration uniformly over the entire semiconductor layer, thereby improving the luminous efficiency. To this end, the semiconductor device of the embodiment may include a light emitting structure 110 that improves dislocation.

In the embodiment, the ultraviolet light emitting device 100 having a wavelength range of 200 nm to 400 nm is described as an example.

The light emitting device 100 may include a substrate 101, a light emitting structure 110, and first and second electrodes 151 and 153.

The light emitting structure 110 includes an AlN template 111, a first conductive semiconductor layer 112, an active layer 114, an electron blocking layer 130, The second conductive type first semiconductor layer 116, the second conductive type second semiconductor layer 118a, and the second conductive type third semiconductor layer 118b.

The substrate 101 may be formed of a material having excellent thermal conductivity, or may be a conductive substrate or an insulating substrate. For example, the substrate 101 is a sapphire (Al ₂ O _3), SiC, Si, GaAs, GaN, ZnO, GaP, InP, Ge, and Ga ₂ 0 ₃ May be used. A concavo-convex structure may be formed on the substrate 101, but the present invention is not limited thereto.

The AlN template 111 may be formed on the substrate 101. The AlN template 111 may include a buffer function. The AlN template 111 may alleviate the lattice mismatch between the material of the light emitting structure 110 formed on the AlN template 111 and the substrate 101. The AlN template 111 may include AlN, Group 5 or Group 6 compound semiconductors such as GaN, InN, InGaN, AlGaN, InAlGaN, and AlInN.

The AlN template 111 may be grown on the substrate 101 to improve defects due to the difference in lattice constant of the AlGaN-based semiconductor layers to be grown thereafter. The AlN template 111 may have a fully-strained epitaxial structure, thereby improving the luminous efficiency in the growth of a semiconductor layer having an ultraviolet wavelength. That is, the AlN template 111 can improve the crystallinity of the AlGaN-based semiconductor layers to be grown, thereby improving the luminous efficiency of the ultraviolet light-emitting device 100.

The first conductive semiconductor layer 112 may be formed of at least one of a semiconductor compound, for example, a Group III-V compound semiconductor or a Group II-VI compound semiconductor. The first conductivity type semiconductor layer 112 may be a single layer or a multilayer. The first conductive semiconductor layer 112 may be doped with a first conductive dopant. For example, when the first conductive semiconductor layer 112 is an n-type semiconductor layer, it may include an n-type dopant. For example, the n-type dopant may include but is not limited to Si, Ge, Sn, Se, and Te.

Embodiment of the first conductivity type semiconductor layer 112 is Al _x Ga _{1 -} but may include semiconductor materials having a composition formula of _{x N (0 <x <1} ), but is not limited to such. For example, the first conductive semiconductor layer 112 may be formed of one or more of AlGaP, InGaP, AlInGaP, InP, GaN, InN, AlN, InGaN, AlGaN, InAlGaN, AlInN, AlGaAs, InGaAs, AlInGaAs, .

The active layer 114 may be disposed on the first conductive semiconductor layer 112. The active layer 114 may be formed of at least one of a single quantum well structure, a multi quantum well (MQW) structure, a quantum-wire structure, or a quantum dot structure. The active layer 114 is formed by injecting electrons (or holes) injected through the first conductive type second semiconductor layer 112b and holes (or electrons) injected through the second conductive type first semiconductor layer 116 And emits light according to a band gap difference of an energy band according to the material of the active layer 114. [

The active layer 114 may be made of a compound semiconductor. The active layer 114 may be formed of at least one of compound semiconductors such as Group 3-Group 5 or Group 2-6. The active layer 114 may include a quantum well and a quantum wall. When the active layer 114 is implemented as a multiple quantum well structure, quantum wells and quantum wells can be alternately arranged. The quantum well and the quantum wall may be formed of any one or more pairs of AlGaN / GaN, AlGaN / AlGaN, InGaN / InGaN, InAlGaN / GaN, GaAs / AlGaAs, InGaAs / AlGaAs, GaP / AlGaP and InGaP AlGaP But is not limited thereto.

The EBL 130 may be disposed on the active layer 114. The EBL 130 may include a second dopant. The EBL 130 of the embodiment may be a single layer or a multi-layer structure. The EBL 130 may include at least one of Group 3-Group 5 or Group 2-VI compound semiconductors, but is not limited thereto. The EBL 130 may be doped with a second conductivity type dopant. For example, when the EBL 130 is a p-type semiconductor layer, the second conductive dopant may include Mg, Zn, Ca, Sr, and Ba as a p-type dopant.

The second conductive type first semiconductor layer 116 may be disposed on the EBL 130. The second conductive type first semiconductor layer 116 may be formed of a compound semiconductor such as a group III-V element or a group II-VI element. For example, the second conductive type first semiconductor layer 116 may be formed of any one or more of GaN, InN, AlN, InGaN, AlGaN, InAlGaN, AlInN, AlGaAs, InGaAs, AlInGaAs, GaP, AlGaP, InGaP, AlInGaP, . The second conductive type first semiconductor layer 116 of the embodiment may include an AlGaN-based semiconductor material. The second conductive type first semiconductor layer 116 may be doped with a second conductive type dopant. When the second conductive type first semiconductor layer 116 is a p-type semiconductor layer, the second conductive type dopant may include Mg, Zn, Ca, Sr, and Ba as a p-type dopant.

The second conductive type second semiconductor layer 118a may be disposed on the second conductive type first semiconductor layer 116. The second conductive type second semiconductor layer 118a may include a function of bending the electric potential D from the second conductive type first semiconductor layer 116. For this, the second conductive type second semiconductor layer 118a may be 3D (three dimensional) grown. The second conductive type second semiconductor layer 118a may have a function of buffering the second conductive type third semiconductor layer 118b grown thereafter. The second conductive type second semiconductor layer 118a bends the potential D from the second conductive type first semiconductor layer 116 to improve defects so that the second conductive type second semiconductor layer 118b is removed from the EBL 130 to the active layer 114 Back diffusion of the two-conductivity-type dopant can be improved. 3, the second conductivity type dopant of the second conductive type first semiconductor layer 116 may be uniformly doped. That is, the embodiment can realize stable doping of the second conductive type first semiconductor layer 116.

The bending of the potential D may be performed by connecting a straight line connecting the start point DS and the end point DT of the potential D from the second conductive type first semiconductor layer 116, The angle? Formed by the upper surface of the semiconductor layer 116 may be less than 45 degrees. Here, when the angle formed by the straight line and the upper surface of the second conductive type second semiconductor layer 118a is greater than 45 degrees, the second conductive type second semiconductor layer 118a is electrically connected to the second conductive type semiconductor layer 118a, The potential D can be propagated to the third semiconductor layer 118b.

The second conductive type second semiconductor layer 118a may be GaN including a second conductive type dopant, but the present invention is not limited thereto. The second conductive type second semiconductor layer 118a may bend the potential D from the second conductive type semiconductor layer 116 by 3D growth. That is, the second conductive type second semiconductor layer 118a bends the potential D from the second conductive type first semiconductor layer 116 in the A-plane direction in the C-plane direction, It is possible to improve the electric potential D propagation to the conductive type third semiconductor layer 118b and to reduce the TDD at the interface with the second conductive type third semiconductor layer 118b.

4 and 5, RSM DATA of the comparative example in which the second conductive type second semiconductor layer 118a is omitted is shown in FIG. 4, and FIG. 5 is a cross-sectional view of the second conductive type semiconductor layer 118a including the second conductive type second semiconductor layer 118a. RSM DATA of the embodiment. Here, the RSM DATA is a strain relaxation parameter, and the comparative example is a second conductivity type first semiconductor layer of AlGaN and a 2D mode P-GaN, and the embodiment is an AlGaN second conductivity type first semiconductor layer And a second conductivity type second semiconductor layer 118a of 3D mode P-GaN.

Here, the x-axis is inversely proportional to the A-plane lattice constant difference (1 / A-plane lattice constant difference), and the Y-axis is inversely proportional to the C-plane lattice constant difference (1 / C-plane lattice constant difference).

The embodiment shows a horizontal mismatch between the second conductive type first semiconductor layer 116 of AlGaN and the second conductive type second semiconductor layer 118a of 3D mode P-GaN in the x-axis direction by 10 %. The horizontal misalignment may be caused by a strain distribution indicating the extent to which strain is retained when growing the second conductive type first semiconductor layer 116 and the second conductive type second semiconductor layer 118a of the 3D mode P- As a variable, the potential (D) and the defect can be improved. Here, the strain is defined as a strain can be minimized by minimizing a change in strain as the amount of change in the x-axis is small, and a strain can be maintained or a strain can not be released when the strain is minimized. can do. The retention of the strain results in a small A-plane lattice constant difference between the second conductive type first semiconductor layer 116 of AlGaN and the second conductive type second semiconductor layer 118a of 3D mode P-GaN .

The thickness of the second conductive type second semiconductor layer 118a may be 10 nm to 50 nm. When the thickness of the second conductive type second semiconductor layer 118a is less than 10 nm, it is difficult to bend the potential D from the second conductive type first semiconductor layer 116, 2-conductivity-type third semiconductor layer 118b. Here, the potential D propagated to the second conductive type third semiconductor layer 118b may be V-pits or cracks. The V-pits or cracks may cause a leakage current. If the thickness of the second conductive type second semiconductor layer 118a is more than 50 nm, defects may be generated from the inside of the second conductive type second semiconductor layer 118a grown in an island shape.

The root mean square (RMS) between the second conductive type second semiconductor layer 118a and the second conductive type third semiconductor layer 118b may be 1.0 nm or more, for example, 1.0 nm to 5.0 nm. The second conductive type second semiconductor layer 118a of the embodiment is 3D-grown in an island shape to form a second conductive type semiconductor layer 118a between the second conductive type second semiconductor layer 118a and the second conductive type third semiconductor layer 118b And may include interfacial roughness (RMS).

The doping concentration of the second conductive type second semiconductor layer 118a may correspond to the second conductive type first semiconductor layer 116 and the EBL 130. For example, the doping concentration of the second conductive type second semiconductor layer 118a may be 1E19 to 5E19. The second conductive type second semiconductor layer 118a may have a lower doping concentration than the second conductive type third semiconductor layer 118b. The doping concentration of the second conductive type third semiconductor layer 118b may be higher than that of the second conductive type second semiconductor layer 118a, the second conductive type first semiconductor layer 116, and the EBL 130 . For example, the doping concentration of the second conductive type third semiconductor layer 118b may be 5E19 to 1E20. The second conductive type third semiconductor layer 118b may include a higher doping concentration than the second conductive type second semiconductor layer 118a, the second conductive type first semiconductor layer 116, and the EBL 130, Ohmic contact with the second electrode 153 can be realized.

The second conductive type third semiconductor layer 118b may be disposed on the second conductive type second semiconductor layer 118a. The second conductive type third semiconductor layer 118b may be a GaN including a second conductive type dopant for ohmic operation of the second conductive type first semiconductor layer 116 and the second electrode 153, It is not. The surface of the second conductive type third semiconductor layer 118b directly contacting the second electrode 153 may be flat. For this, the second conductive type third semiconductor layer 118b may be formed by a 2D (two dimensional) mode growth method. 6 is a view showing the surface of the second conductive type third semiconductor layer 118b of the embodiment. The second conductive type third semiconductor layer 118b of the embodiment may have a thickness of 100 nm to 300 nm.

When the thickness of the second conductive type third semiconductor layer 118b is less than 100 nm, ohmic contact with the second electrode 153 may be difficult, and when the thickness of the second conductive type third semiconductor layer 118b is 300 Nm, a new defect may occur in the second conductive type third semiconductor layer 118b.

The second conductive type third semiconductor layer 118b may have a surface roughness (RMS) of 1 nm or less, for example, 0.1 nm to 1.0 nm. The second conductive type second semiconductor layer 116b of the embodiment may include a surface roughness (RMS) of 1 nm or less to improve the reliability of contact with the second electrode 153 formed later.

Here, the first conductive semiconductor layer 112 may include an n-type semiconductor layer, the second conductive type first semiconductor layer 116, the second conductive type second semiconductor layer 118a, The third semiconductor layer 118b is a p-type semiconductor layer, but is not limited thereto. The light emitting structure 110 may have any one of an n-p junction structure, a p-n junction structure, an n-p-n junction structure, and a p-n-p junction structure.

The first electrode 151 may be disposed on the first conductive type second semiconductor layer 112b. The first electrode 151 may be electrically connected to the first conductive type second semiconductor layer 112b. The first electrode 151 may be electrically insulated from the second electrode 153. The first electrode 151 may be a conductive oxide, a conductive nitride, or a metal. For example, the first electrode 151 may be formed of ITO (Indium Tin Oxide), ITON (ITO), IZO (Indium Zinc Oxide), IZON (IZO Nitride), AZO (Aluminum Zinc Oxide) IZTO (Indium Zinc Tin Oxide), IZO (Indium Aluminum Zinc Oxide), IGZO (Indium Gallium Zinc Oxide), IGTO (Indium Gallium Tin Oxide), ATO (Antimony Tin Oxide) ), ZnO, IrOx, RuOx, NiO, Au, Cu, Ni, Ti, Ti-W, Cr, W, Pt, V, Fe and Mo. have.

The second electrode 153 may be disposed on the second conductive type third semiconductor layer 118b. The second electrode 153 may be in ohmic contact with the second conductive type third semiconductor layer 118b. The second electrode 153 may be a conductive oxide, a conductive nitride, or a metal. For example, the second electrode 153 may be formed of ITO (Indium Tin Oxide), ITON (ITO), IZO (Indium Zinc Oxide), IZON (IZO Nitride), AZO (Aluminum Zinc Oxide) IZTO (Indium Zinc Tin Oxide), IZO (Indium Aluminum Zinc Oxide), IGZO (Indium Gallium Zinc Oxide), IGTO (Indium Gallium Tin Oxide), ATO (Antimony Tin Oxide) ), ZnO, IrOx, RuOx, NiO, Au, Cu, Ni, Ti, Ti-W, Cr, W, Pt, V, Fe and Mo. have.

The embodiment can improve the defect by bending the potential D from the second conductive type first semiconductor layer 116 by the 3D (three dimensional) grown second conductive type second semiconductor layer 118a have. That is, in the embodiment, the second conductive type second semiconductor layer 118a prevents the potential D from propagating to the second conductive type third semiconductor layer 118b to be grown thereafter, The TDD (Threading dislocation Density) can be reduced at the interface between the first conductive semiconductor layer 118a and the second conductive semiconductor layer 118b.

The second conductive type second semiconductor layer 118a grown in 3D mode on the second conductive type first semiconductor layer 116 is disposed so that the electric potential of the first conductive type semiconductor layer 116 ) Can be bent to improve the crystallinity.

The embodiment can improve the luminous efficiency by reducing the TDD (Threading dislocation Density) of the final semiconductor layer by improving the propagation of the potential (D).

The embodiment improves the back diffusion of the p dopant from the EBL to the active layer by keeping the doping concentration of the second conductive type dopant of the second conductive type first semiconductor layer 116, EBL 130 constant. So that the light extraction efficiency can be improved.

The embodiment can improve dislocation D and defects and improve electrical characteristics due to leakage current.

The embodiment can realize the fully TE polarized light of the ultraviolet light emitting element by improving the dislocation D and defects.

7 to 10 are cross-sectional views showing a method of manufacturing a semiconductor device of the embodiment.

7 and 8, a method of manufacturing a light emitting device according to an embodiment of the present invention includes firstly an AlN template 111, a first conductive semiconductor layer 112, an active layer 114, an EBL 130, The second conductive type first semiconductor layer 116, the second conductive type second semiconductor layer 118a, and the second conductive type third semiconductor layer 118b may be formed.

A connection relationship between materials and configurations of the substrate 101, the AlN template 111, the first conductivity type semiconductor layer 112, the active layer 114, the EBL 130, and the second conductivity type first semiconductor layer 116 The technical features of Figs. 1 and 2 can be adopted.

The AlN template 111, the first conductive semiconductor layer 112, the active layer 114, the EBL 130, the first conductive semiconductor layer 116, and the second conductive- A metal organic chemical vapor deposition (MOCVD), a chemical vapor deposition (CVD), a plasma enhanced chemical vapor deposition (PECVD), a molecular beam epitaxy (MBE) A hydride vapor phase epitaxy (HVPE), or the like, but the present invention is not limited thereto.

The second conductive type second semiconductor layer 118a may be formed on the second conductive type semiconductor layer 116. The second conductive type second semiconductor layer 118a may include a function of bending a potential from the second conductive type first semiconductor layer 116. [ For this, the second conductive type second semiconductor layer 118a may be 3D grown. The second conductive type second semiconductor layer 118a may have a function of buffering the second conductive type third semiconductor layer 118b grown thereafter. The second conductive type second semiconductor layer 118a bends the potential from the second conductive type first semiconductor layer 116 to improve the defect so that the second conductive type second semiconductor layer 118a is electrically coupled to the active layer 114 from the EBL 130, The back diffusion of the dopant can be improved. The embodiment can realize stable doping of the first semiconductor layer 116 of the second conductivity type.

The second conductive type second semiconductor layer 118a may be GaN including a second conductive type dopant, but the present invention is not limited thereto. The second conductive type second semiconductor layer 118a may bend the potential from the second conductive type first semiconductor layer 116 by 3D growth. That is, the second conductive type second semiconductor layer 118a bends the potential from the second conductive type first semiconductor layer 116 in the A-plane direction in the C-plane direction, 3 semiconductor layer 118b can be improved and the TDD (Threading dislocation Density) at the interface with the second conductive type third semiconductor layer 118b can be reduced.

The thickness of the second conductive type second semiconductor layer 118a may be 10 nm to 50 nm. When the thickness of the second conductive type second semiconductor layer 118a is less than 10 nm, it is difficult to bend the potential from the second conductive type first semiconductor layer 116, Lt; / RTI &gt; layer 118b. Here, the electric potential propagated to the second conductive type third semiconductor layer 118b may cause V-pits or cracks. The V-pits or cracks may cause a leakage current. If the thickness of the second conductive type second semiconductor layer 118a is more than 50 nm, defects may be generated from the inside of the second conductive type second semiconductor layer 118a grown in an island shape.

The root mean square (RMS) between the second conductive type second semiconductor layer 118a and the second conductive type third semiconductor layer 118b may be 1.0 nm or more, for example, 1.0 nm to 5.0 nm. The second conductive type second semiconductor layer 118a of the embodiment is 3D-grown in an island shape to form a second conductive type semiconductor layer 118a between the second conductive type second semiconductor layer 118a and the second conductive type third semiconductor layer 118b And may include interfacial roughness (RMS).

The doping concentration of the second conductive type second semiconductor layer 118a may correspond to the second conductive type first semiconductor layer 116 and the EBL 130. For example, the doping concentration of the second conductive type second semiconductor layer 118a may be 1E19 to 5E19. The second conductive type second semiconductor layer 118a may have a lower doping concentration than the second conductive type third semiconductor layer 118b. The doping concentration of the second conductive type third semiconductor layer 118b may be higher than that of the second conductive type second semiconductor layer 118a, the second conductive type first semiconductor layer 116, and the EBL 130 . For example, the doping concentration of the second conductive type third semiconductor layer 118b may be 5E19 to 1E20. The second conductive type third semiconductor layer 118b may include a higher doping concentration than the second conductive type second semiconductor layer 118a, the second conductive type first semiconductor layer 116, and the EBL 130, Ohmic contact with the second electrode 153 can be realized.

The second conductive type third semiconductor layer 118b may be disposed on the second conductive type second semiconductor layer 118a. The second conductive type third semiconductor layer 118b may be a GaN including a second conductive type dopant for ohmic operation of the second conductive type first semiconductor layer 116 and the second electrode 153, It is not. The surface of the second conductive type third semiconductor layer 118b directly contacting the second electrode 153 may be flat. For this, the second conductive type third semiconductor layer 118b may be formed by a 2D growth method. 6 is a view showing the surface of the second conductive type third semiconductor layer 118b of the embodiment. The second conductive type third semiconductor layer 118b of the embodiment may have a thickness of 100 nm to 300 nm.

When the thickness of the second conductive type third semiconductor layer 118b is less than 100 nm, ohmic contact with the second electrode 153 may be difficult, and when the thickness of the second conductive type third semiconductor layer 118b is 300 Nm, a new defect may occur in the second conductive type third semiconductor layer 118b.

The second conductive type third semiconductor layer 118b may have a surface roughness (RMS) of 1 nm or less, for example, 0.1 nm to 1.0 nm. The second conductive type second semiconductor layer 116b of the embodiment may include a surface roughness (RMS) of 1 nm or less to improve the reliability of contact with the second electrode 153 formed later.

Here, the first conductive semiconductor layer 112 may include an n-type semiconductor layer, the second conductive type first semiconductor layer 116, the second conductive type second semiconductor layer 118a, The third semiconductor layer 118b is a p-type semiconductor layer, but is not limited thereto. The light emitting structure 110 may have any one of an n-p junction structure, a p-n junction structure, an n-p-n junction structure, and a p-n-p junction structure.

Referring to FIG. 9, the first and second electrodes 151 and 153 may be formed on the light emitting structure 110. The light emitting structure 110 may be formed by mesa etching so that a portion of the first conductive semiconductor layer 112 is partially exposed to the active layer 114, the EBL 130, the second conductive semiconductor layer 116, And may be exposed from the second semiconductor layer 118a and the second conductive type third semiconductor layer 118b.

The first electrode 151 may be formed on the exposed first conductive semiconductor layer 112. The first electrode 151 may be electrically connected to the first conductive semiconductor layer 112. The first electrode 151 may be electrically insulated from the second electrode 153.

The second electrode 153 may be formed on the first conductive semiconductor layer 116. The second electrode 153 may be electrically connected to the second conductive type first semiconductor layer 116.

The first and second electrodes 151 and 153 may be a conductive oxide, a conductive nitride, or a metal. For example, the first and second electrodes 151 and 153 may be formed of ITO (indium tin oxide), ITON (indium tin oxide), IZO (indium zinc oxide), IZON (indium zinc oxide), AZO Gallium Zinc Oxide), IZTO (Indium Zinc Tin Oxide), IZO (Indium Aluminum Zinc Oxide), IGZO (Indium Gallium Zinc Oxide), IGTO (Indium Gallium Tin Oxide), ATO (Antimony Tin Oxide) , IZON (IZO Nitride), ZnO, IrOx, RuOx, NiO, Au, Cu, Ni, Ti, Ti-W, Cr, W, Pt, And may be formed in multiple layers.

Referring to FIG. 10, the embodiment may be a flip chip structure in which the first and second electrodes 151 and 153 are disposed below. The first insulating layer 161 may be formed on the light emitting structure 110 by exposing a portion of the lower surface of the first and second electrodes 151 and 153. The first insulating layer 161 may be in contact with the bottom of the light emitting structure 110 in which the first and second electrodes 151 and 153 are disposed.

First and second connection electrodes 171 and 173 may be formed on the lower surfaces of the first and second electrodes 151 and 153 exposed from the first insulation layer 161. The first and second connection electrodes 171 and 173 may be formed by a plating process, but the present invention is not limited thereto. The first insulating layer 161 may be an oxide or a nitride. For example, the first insulating layer 161 may include at least one of SiO ₂ , Si _x O _y , Si ₃ N ₄ , Si _x N _y , SiO _x N _y , Al ₂ O ₃ , TiO ₂ , Can be selected.

The first and second connection electrodes 171 and 173 may be a metal or an alloy including at least one of Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Cu, have. The first and second connection electrodes 171 and 173 are formed of a metal or an alloy of ITO (Indium Tin Oxide), IZO (Indium-Zinc-Oxide), IZTO (Indium-Zinc-Tin-Oxide) Indium-Aluminum-Zinc-Oxide (IGZO), Indium-Gallium-Tin-Oxide (IGTO), Aluminum-Zinc-Oxide (AZO), and Antimony-Tin-Oxide It may be a single layer or multiple layers of a transparent conductive material.

The second insulating layer 163 may be formed under the first insulating layer 161 and may be in direct contact with the first insulating layer 161. The second insulating layer 163 may be formed on the side of the first and second connection electrodes 171 and 173 while exposing the lower portions of the first and second connection electrodes 171 and 173. The second insulation layer 163 may be formed by adding a thermal diffusion material to the resin material such as silicon or epoxy. The heat spreader may include at least one material selected from the group consisting of oxides, nitrides, fluorides, and sulfides having a material such as Al, Cr, Si, Ti, Zn, and Zr. The heat spreader may be defined as a powder particle, a grain, a filler, or an additive having a predetermined size. The second insulating layer 163 may be omitted.

The first and second pads 181 and 183 may be formed on the first and second connection electrodes 171 and 173 exposed from the second insulating layer 163. The first and second pads 181 and 183 may be a metal or an alloy including at least one of Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Cu, . The first and second pads 181 and 183 may be formed of a metal or an alloy of ITO (Indium-Tin-Oxide), IZO (Indium-Zinc-Oxide), IZTO (Indium-Zinc-Tin- Transparent, such as Aluminum-Zinc-Oxide (IGZO), Indium-Gallium-Zinc-Oxide (IGZO), IGTO (Indium-Gallium-Tin- Oxide), AZO It may be a single layer or multiple layers of conductive material.

Although the embodiment includes the substrate 101 disposed on the first conductive type semiconductor layer 112, the present invention is not limited thereto. For example, the substrate 101 may be removed by a laser lift off (LLO) process. Here, the laser lift-off process (LLO) is a process of irradiating a laser beam to the lower surface of the substrate 101 to peel the substrate 101 and the light emitting structure 110 from each other.

In the embodiment, the second conductive type second semiconductor layer 118a grown in 3D mode on the second conductive type first semiconductor layer 116 is disposed to bend the potential from the second conductive type first semiconductor layer 116 Whereby the crystallinity can be improved.

Embodiments can improve the emission efficiency by reducing TDD (Threading dislocation Density) of the final semiconductor layer by improving the propagation of potential.

The embodiment improves the back diffusion of the p dopant from the EBL to the active layer by keeping the doping concentration of the second conductive type dopant of the second conductive type first semiconductor layer 116, EBL 130 constant. So that the light extraction efficiency can be improved.

The embodiment can improve dislocations and defects to improve electrical characteristics due to leakage currents.

Embodiments can improve dislocations and defects to realize fully TE polarized light of an ultraviolet light emitting device.

11 is a cross-sectional view illustrating a light emitting device package according to an embodiment.

11, the light emitting device package 200 includes a light emitting device 100, a package body 201, a heat radiating frame 210, a protection device 260, first and second lead frames 220 , 230).

The package body 201 may include at least one of a light-transmitting material, a reflective material, and an insulating material. The package body 201 may include a material having a reflectance higher than that of the light emitted from the light emitting device 100. The package body 201 may be a resin-based insulating material. For example, the package body 201 is a polyphthalamide (PPA: Polyphthalamide), a resin material, a silicone such as an epoxy or silicone (Si), metallic material, PSG (photo sensitive glass), sapphire (Al ₂ O _3), printing And a circuit board (PCB). The package body 201 may have a square shape, for example, but the shape thereof may not be audible. The top view shape of the package body 201 may be circular or polygonal.

The package body 201 may be coupled to the first and second lead frames 220 and 230. The body 120 may include a cavity 203 for exposing a portion of the upper surface of the first and second lead frames 220 and 230. The cavity 203 may expose a part of the upper surface of the first lead frame 220 and may expose a part of the upper surface of the second lead frame 230.

The first and second lead frames 220 and 230 may be spaced apart from each other and coupled with the package body 201. The second lead frame 230 may include the light emitting device 100 and the protection device 260. The first wire 100W1 of the light emitting device 100 may be connected to the first lead frame 220, And the wire 260W of the protection element 260 may be connected, but the present invention is not limited thereto. The first and second lead frames 220 and 230 may include a conductive material. For example, the first and second lead frames 220 and 230 may include at least one of titanium (Ti), copper (Cu), nickel (Ni), gold (Au), chromium (Cr), tantalum (Ta) (Al), tin (Sn), silver (Ag), phosphorous (P), iron (Fe), tin . For example, the first and second lead frames 220 and 230 of the embodiment may be composed of a base layer including copper (Cu) and an antioxidant layer including silver (Ag) covering the base layer, no.

The second lead frame 230 includes a first lead portion 231a exposed in a center region of the cavity 203 and a second lead portion 231b symmetrically diagonally intersecting the first lead frame 220, A third lead part 231c disposed in a corner area of the cavity 203 in which the protection element 260 is mounted and a diagonal corner area. The first to third lead portions 231a, 231b and 131c are formed on the upper surface of the second lead frame 230 exposed on the bottom surface of the cavity 203, .

The first lead frame 220 may have a diagonal bent structure symmetrical to the second lead portion 231b, but the present invention is not limited thereto.

The heat radiating frame 210 includes first and second radiating electrodes 211 and 213 and the first radiating electrode 211 includes a first pad portion 211a connected to the first wire 100W1 And the second radiation electrode 213 may include a second pad portion 213a connected to the second wire 100W2.

The light emitting device 100 may be mounted on the heat dissipating frame 210. Although the light emitting device package including the heat dissipating frame 210 is limited in the embodiment, the heat dissipating frame 210 may be omitted. When the constant heat dissipating frame 210 is omitted, the light emitting device 100 may be disposed on the package body 201. The light emitting device 100 may include the technical features of FIGS.

The protection element 260 may be disposed on the third lead portion 231c. The protection element 260 may be disposed on the upper surface of the second lead frame 230 exposed from the package body 201. The protection element 260 may be a Zener diode, a thyristor, a TVS (Transient Voltage Suppression), or the like, but is not limited thereto. The protection element 160 of the embodiment will be described as a zener diode that protects the light emitting device 100 from ESD (Electro Static Discharge). The protection element 260 may be connected to the first lead frame 130 through a wire.

The light emitting device package of the embodiment includes the light emitting device 100 that improves the lattice constant difference between the semiconductor layers, and is capable of realizing the fully TE polarized light of the ultraviolet light emitting device in particular.

The above-described light emitting device is constituted by a light emitting device package and can be used as a light source of an illumination system. The light emitting device package may include, for example, a body having a cavity and a lead electrode coupled to the body, and the light emitting device may be disposed on the body and electrically connected to the lead electrode.

The light emitting device can be used as a light source of a video display device or a lighting device, for example.

When used as a backlight unit of a video display device, it can be used as an edge-type backlight unit or as a direct-type backlight unit. When used as a light source of a lighting device, it can be used as a regulator or bulb type. It is possible.

The light emitting element includes a laser diode in addition to the light emitting diode described above.

The laser diode may include the first conductivity type semiconductor layer, the active layer and the second conductivity type semiconductor layer having the above-described structure, like the light emitting element. Then, electro-luminescence (electroluminescence) phenomenon in which light is emitted when an electric current is applied after bonding the p-type first conductivity type semiconductor and the n-type second conductivity type semiconductor is used, And phase. That is, the laser diode can emit light having one specific wavelength (monochromatic beam) with the same phase and in the same direction by using a phenomenon called stimulated emission and a constructive interference phenomenon. It can be used for optical communication, medical equipment and semiconductor processing equipment.

As the light receiving element, a photodetector, which is a kind of transducer that detects light and converts the intensity of the light into an electric signal, is exemplified. As such a photodetector, a photodiode (e.g., a PD with a peak wavelength in a visible blind spectral region or a true blind spectral region), a photodiode (e.g., a photodiode such as a photodiode (silicon, selenium), a photoconductive element (cadmium sulfide, cadmium selenide) , Photomultiplier tube, phototube (vacuum, gas-filled), IR (Infra-Red) detector, and the like.

In addition, a semiconductor device such as a photodetector may be fabricated using a direct bandgap semiconductor, which is generally excellent in photo-conversion efficiency. Alternatively, the photodetector has a variety of structures, and the most general structure includes a pinned photodetector using a pn junction, a Schottky photodetector using a Schottky junction, and a metal-semiconductor metal (MSM) photodetector have.

The photodiode, like the light emitting device, may include the first conductivity type semiconductor layer having the structure described above, the active layer, and the second conductivity type semiconductor layer, and may have a pn junction or a pin structure. The photodiode operates by applying reverse bias or zero bias. When light is incident on the photodiode, electrons and holes are generated and a current flows. At this time, the magnitude of the current may be approximately proportional to the intensity of the light incident on the photodiode.

A photovoltaic cell or a solar cell is a type of photodiode that can convert light into current. The solar cell, like the light emitting device, may include the first conductivity type semiconductor layer, the active layer and the second conductivity type semiconductor layer having the above-described structure.

In addition, it can be used as a rectifier of an electronic circuit through a rectifying characteristic of a general diode using a p-n junction, and can be applied to an oscillation circuit or the like by being applied to a microwave circuit.

In addition, the above-described semiconductor element is not necessarily implemented as a semiconductor, and may further include a metal material as the case may be. For example, a semiconductor device such as a light receiving element may be implemented using at least one of Ag, Al, Au, In, Ga, N, Zn, Se, P, or As, Or may be implemented using a doped semiconductor material or an intrinsic semiconductor material. While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It will be understood that various modifications and applications are possible. For example, each component specifically shown in the embodiments can be modified and implemented. It is to be understood that all changes and modifications that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

101: substrate
110: light emitting structure
111: AlN template
112: first conductive type semiconductor layer
114:
130: Electron blocking layer (EBL)
116: second conductive type first semiconductor layer
118a: second conductive type second semiconductor layer
118b: the second conductive type third semiconductor layer

Claims (14)

A first conductive semiconductor layer;
An active layer on the first conductive semiconductor layer;
An electron blocking layer (EBL) on the active layer;
A second conductive type first semiconductor layer disposed on the EBL and including AlGaN;
A second conductive type second semiconductor layer on the second conductive type first semiconductor layer; And
And a second conductive type third semiconductor layer on the second conductive type second semiconductor layer,
Wherein a root mean square (RMS) between the second conductive type second semiconductor layer and the second conductive type third semiconductor layer is greater than a surface roughness of the second conductive type third semiconductor layer.
The method according to claim 1,
And the interface roughness between the second conductive type second semiconductor layer and the second conductive type third semiconductor layer is 1.0 nm to 5.0 nm.
The method according to claim 1,
And the surface roughness of the second conductive type third semiconductor layer is 0.1 nm to 1.0 nm.
The method according to claim 1,
And the second conductive type second semiconductor layer has a thickness of 10 nm to 50 nm.
The method according to claim 1,
And the second conductive type third semiconductor layer has a thickness of 100 nm to 300 nm.
The method according to claim 1,
And the second conductive type third semiconductor layer has a higher doping concentration than the EBL, the second conductive type first semiconductor layer, and the second conductive type second semiconductor layer.
The method according to claim 1,
And the second conductive type second semiconductor layer has a doping concentration of 1E19 to 5E19.
The method according to claim 1,
And the second conductive type third semiconductor layer has a doping concentration of 5E19 to 1E20.
A first conductive semiconductor layer on the substrate; an active layer on the first conductive semiconductor layer; Growing an EBL on the active layer and a first conductive semiconductor layer on the EBL;
Growing a second conductive type second semiconductor layer on the second conductive type first semiconductor layer in a 3D (three dimensional) mode; And
And growing a second conductive type third semiconductor layer on the second conductive type second semiconductor layer in a 2D (2D) mode.
10. The method of claim 9,
Wherein the second conductive type first semiconductor layer has a composition formula of Al _x Ga _1-x N (0 < x < 1)
Wherein a root mean square (RMS) between the second conductive type second semiconductor layer and the second conductive type third semiconductor layer is greater than a surface roughness of the second conductive type third semiconductor layer.
10. The method of claim 9,
The interface roughness of the second conductivity type second semiconductor layer and the second conductivity type third semiconductor layer is 1.0 nm to 5.0 nm,
And the surface roughness of the second conductivity type third semiconductor layer is 0.1 nm to 1.0 nm.
10. The method of claim 9,
The second conductive type second semiconductor layer has a thickness of 10 nm to 50 nm,
And the second conductive type third semiconductor layer has a thickness of 100 nm to 300 nm.
10. The method of claim 9,
The second conductive type second semiconductor layer has a doping concentration of 1E19 to 5E19,
And the second conductive type third semiconductor layer has a doping concentration of 5E19 to 1E20.
A package body;
First and second lead frames coupled to the package body; And
The light emitting device package according to any one of claims 1 to 8, wherein the light emitting device is disposed on the package body.

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