WO2016093257A1 - Élément électroluminescent et procédé pour sa fabrication - Google Patents
Élément électroluminescent et procédé pour sa fabrication Download PDFInfo
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- WO2016093257A1 WO2016093257A1 PCT/JP2015/084461 JP2015084461W WO2016093257A1 WO 2016093257 A1 WO2016093257 A1 WO 2016093257A1 JP 2015084461 W JP2015084461 W JP 2015084461W WO 2016093257 A1 WO2016093257 A1 WO 2016093257A1
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L33/00—Semiconductor devices having potential barriers specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L33/02—Semiconductor devices having potential barriers specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor bodies
- H01L33/20—Semiconductor devices having potential barriers specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor bodies with a particular shape, e.g. curved or truncated substrate
- H01L33/22—Roughened surfaces, e.g. at the interface between epitaxial layers
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L33/00—Semiconductor devices having potential barriers specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L33/02—Semiconductor devices having potential barriers specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor bodies
- H01L33/26—Materials of the light emitting region
- H01L33/30—Materials of the light emitting region containing only elements of Group III and Group V of the Periodic Table
- H01L33/32—Materials of the light emitting region containing only elements of Group III and Group V of the Periodic Table containing nitrogen
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L33/00—Semiconductor devices having potential barriers specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L33/36—Semiconductor devices having potential barriers specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the electrodes
Definitions
- the present invention relates to a light emitting element and a manufacturing method thereof.
- LEDs light emitting diodes
- OLEDs organic ELs
- EQE external quantum efficiency
- IQE internal quantum efficiency
- EIE electron injection efficiency
- LEE light extraction efficiency
- the GaN substrate LED has advantages such as no lattice distortion and no crystal defects at the interface, and a conductive substrate with good heat dissipation, the IQE ⁇ EIE value is very excellent.
- the refractive index of GaN is as large as 2.5 at a wavelength of 455 nm, and the light extraction efficiency is poor because 80% or more of the emitted light is totally reflected and internally lost at the GaN / air interface.
- a technique for forming a photonic crystal periodic structure having a period of about the wavelength of light in the light extraction layer has been introduced.
- the photonic crystal periodic structure is generally formed at the interface between two structures having different refractive indexes, and is generally an unevenness mainly composed of a pillar structure or a hole structure. And in the area
- the light emitting device described in Patent Document 2 below has a flip chip structure in which the main light extraction surface is an n-type semiconductor layer, and a recess having two or more inclined surfaces is formed on the back surface to improve the light extraction efficiency. ing. Further, the light distribution is controlled so that the light is efficiently emitted above the concave portion.
- the concave portion having two or more inclined surfaces created in the light emitting element described in Patent Document 2 requires precise control of the angle of each inclined surface and the size of the bottom surface of the concave portion, and thus the manufacturing process is complicated. There are problems such as becoming.
- An object of the present invention is to provide a light emitting device having high light extraction efficiency from the back surface of a GaN substrate and excellent in light distribution and a method for manufacturing the same.
- a semiconductor light emitting device having a photonic crystal periodic structure composed of two structures having a reflective film on the front surface (side) of a GaN substrate and different refractive indexes on the back surface (side) of the GaN substrate.
- the design wavelength ⁇ V in vacuum, the period a and the radius R which are parameters of the periodic structure satisfy the Bragg condition, and the ratio R / a is 0.18 to 0.40.
- gamma point is symmetrical point of the second photonic band (2 nd PB), M point, K
- Or order m 3 when the vertical axis the wavelength lambda V ⁇ 3 in a vacuum of, fourth photonic band (4 th PB) to 4 integer multiples and 5 integral multiples each have a fourth photonic band (4 th PB
- the wavelength ⁇ V ⁇ 4 in the vertical axis represents the fourth photonic band obtained by multiplying the fourth photonic band (4 th PB) by 5, 6 or 7 integers.
- a light-emitting element having a photonic crystal of R / a in contact with or closest to any symmetry point on (4 th PB) on the back surface of a GaN substrate.
- the photonic crystal having each R / a selected above and a depth h of 0.5a or more is simulated by the FDTD method, and the photonic crystal finally determined so that the light extraction efficiency and the light distribution are optimized.
- a light emitting device having a crystal on a back surface of a GaN substrate.
- the present invention is also a method for calculating a parameter of a photonic crystal periodic structure in the semiconductor light emitting device described above, wherein a ratio (R / a) between a period a which is a parameter of the periodic structure and a radius R of the structure is assumed.
- the present invention is a method for calculating a parameter of a photonic crystal periodic structure in the semiconductor light emitting device described above, wherein a ratio (R / a) between a period a, which is a parameter of the periodic structure, and a radius R of the structure is assumed.
- the R / a and the order m corresponding to the desired light distribution are selected, the diameter, period, and depth are determined, and the photonic crystal optimization candidates obtained from the third step to the sixth step are selected.
- a light emitting device having a photonic crystal formed on the back surface of a GaN substrate by a nanoimprint method in which a pattern is transferred onto a substrate with a spin coat on an organic resist in a large area.
- a step of spin-coating a lower layer resist having a high etching selectivity on the substrate onto the substrate, and spin-coating an upper layer resist having fluidity and oxygen resistance function on the lower layer resist, and a photonic crystal pattern on the upper layer A step of exposing the patterned upper layer resist to oxygen plasma to impart oxygen resistance, a step of patterning the lower layer resist with oxygen plasma using the patterned upper layer resist having oxygen resistance as a mask, and Provided is a light emitting device having a photonic crystal formed on a back surface of a GaN substrate by a double layer resist process in which the substrate is dry-etched with ICP plasma using the patterned lower layer resist as a mask.
- the present invention it is possible to provide a light emitting device that has high light extraction efficiency from the back surface of the GaN substrate and is excellent in light distribution.
- FIG. 1A and 1B are a structural cross-sectional view (FIG. 1A) and a plan view (FIG. 1B) showing a configuration example of a light-emitting element according to an embodiment of the present invention.
- GMMA 1st Brillouin area
- region and also is a figure which shows (GAMMA), M, and K point (symmetry point).
- GMMA 1st Brillouin area
- region and also is a figure which shows (GAMMA), M, and K point (symmetry point).
- GMMA 1st Brillouin area
- region and also is a figure which shows (GAMMA
- the photonic band gaps (PBGs) between 1 st PB-2 nd PB, 3 rd PB-4 th PB, and 5 th PB-6 th PB are PBG1, PBG2, and PBG3, respectively. It is a figure which shows the relationship.
- the vertical axis ( ⁇ a / 2 ⁇ c) in terms of the wavelength lambda V in vacuum, the photonic band structure of the lambda V and ka / 2 [pi in order m 1 Bragg condition is satisfied second photonic band (2 nd PB)
- Is a diagram showing the R / a, which is determined by the order m 3, is a diagram showing a condition where fourth photonic band R / a (4 th PB) results in a standing wave.
- the horizontal axis is a diagram showing a photonic band structure of ka / 2 ⁇ .
- the vertical axis ( ⁇ a / 2 ⁇ c) of the fourth photonic band (4 th PB) satisfying the Bragg condition is converted to a wavelength ⁇ V in vacuum and multiplied by an integer of 4; the vertical axis: 3 ⁇ V , and the horizontal axis: ka / It is a figure which shows a 2pi photonic band structure.
- the vertical axis ( ⁇ a / 2 ⁇ c) of the fourth photonic band (4 th PB) satisfying the Bragg condition is converted to a wavelength ⁇ V in vacuum and multiplied by 5 integers, the vertical axis: 3 ⁇ V , and the horizontal axis: ka / It is a figure which shows a 2pi photonic band structure.
- the horizontal axis is a diagram showing a photonic band structure of ka / 2 ⁇ .
- the photonic band gaps (PBGs) between 1 st PB-2 nd PB, 3 rd PB-4 th PB, 5 th PB-6 th PB, 7 th PB-8 th PB are PBG1, PBG2, PBG3 and PBG4 are diagrams showing the relationship between R / a and PBG.
- the vertical axis ( ⁇ a / 2 ⁇ c) in terms of the wavelength lambda V in vacuum, the photonic band structure of the lambda V and ka / 2 [pi in order m 1 Bragg condition is satisfied sixth photonic band (6 th PB)
- the vertical axis ( ⁇ a / 2 ⁇ c) in terms of the wavelength lambda V in vacuum, the photonic band structure of the lambda V and ka / 2 [pi in order m 1 Bragg condition is satisfied eighth photonic band (8 th PB)
- 6 th PB vertical axis: 3 [lambda] V
- An embodiment of the present invention is a semiconductor light emitting device having a photonic crystal periodic structure comprising two structures having a reflective film on the front surface (side) of a GaN substrate and different refractive indexes on the back surface (side) of the GaN substrate
- the photonic crystal periodic structure described above provides a light-emitting element having high light extraction efficiency from the back surface of the GaN substrate and excellent light distribution, and a method for manufacturing the light-emitting element.
- the photonic crystal periodic structure is composed of two structures having different refractive indexes, and the period a and the radius R, which are the periodic structure parameters, are designed under the relationship that satisfies the Bragg condition with the wavelength ⁇ .
- each is a structure designed independently in each periodic photonic crystal structure.
- FIG. 1 is a structural cross-sectional view (FIG. 1 (a)) showing a structural example of the light-emitting element according to the present embodiment, and a plan view (FIG. 1 (b)) viewed from the back side.
- the light emitting device shown in FIG. 1 is a GaN substrate LED.
- GaN substrate LED shown to Fig.1 (a) is an Al reflective film 1, ITO transparent electrode 3, p-type GaN layer 5, and GaN active layer in order from the opposite side (surface side) to a GaN substrate, for example. (Light emitting layer) 7, n-type GaN layer 11, GaN substrate 15, and photonic crystal structure (phc) 17.
- An AlGaN layer may be present.
- This structure is a flip chip structure in which the main light extraction surface is the back surface of the GaN substrate 15, and the photonic crystal structure 17 is formed on the back surface of the GaN substrate 15.
- the photonic crystal structure (phc) 17 is formed on the back surface 15a of the GaN substrate 15 and includes a GaN pillar structure 17a and air 17b.
- the ratio (R / a) of the period a to the radius R is either transmission or reflection of light in the periodic structure of wavelength ⁇ . This value is determined depending on whether or not this is optimized.
- the R / a value is determined by focusing on the TE light. This is because the electric field of TE light tends to accumulate in the dielectric connection structure that exists in parallel in the periodic structure plane, and is reflected by Bragg diffraction on the electric field plane when the periodic structure parameters and the design wavelength satisfy the Bragg condition. It is thought that.
- the ratio (R / a) between the period a and the radius R is an R / a value determined by paying attention to TM light when the purpose is to make light transmission larger than reflection at the interface. .
- R / a value determined by paying attention to TM light when the purpose is to make light transmission larger than reflection at the interface.
- each periodic structure parameter used the FDTD method which makes the variable the period h and radius R determined from R / a according to the order m of Bragg conditions, and the depth h of the periodic structure more than 0.5a as a variable.
- the value is finally determined so that the light extraction efficiency of the entire semiconductor light emitting device with respect to the wavelength ⁇ is maximized.
- the depth h of the periodic structure having a depth of 0.5a or more is a value whose upper limit is limited by the actual processing accuracy.
- the ratio (R / a) between the period a and the radius R is a value determined so as to improve the light transmission effect based on the photonic band of TM light.
- a structure is, for example, a so-called pillar structure in which a structure having a large refractive index (GaN pillar) is formed in a medium having a small refractive index (such as air).
- the optimization of the parameters of the periodic structure may be performed by examining the transmitted light with respect to the TM light for the purpose of transmission (see FIG. 2).
- the electric field of TM light tends to stay in the dielectric spots that exist vertically between the pillar structure rods (pillars) 17a, and when the average refractive index n av , period a, and design wavelength ⁇ satisfy the Bragg condition It can be understood from the scattering by Bragg diffraction on the electric field surface, that is, the TM light is transmitted to the periodic structure surface (interface 15a) in the present embodiment.
- TM light An effective way to know the physical properties of photonic crystals by TM light is to obtain and analyze a photonic band (PB) structure from the plane wave expansion method.
- PB photonic band
- the eigenvalue equation of TM light is derived from the Maxwell equation as follows.
- E ′
- ⁇ relative dielectric constant
- G reciprocal lattice vector
- k wave number
- ⁇ frequency
- c speed of light
- E electric field.
- G reciprocal lattice vectors
- G ⁇ b1, ⁇ b2, and ⁇ (b1 + b2) in the case of a triangular lattice photonic crystal, where the origin and reciprocal lattice point take the minimum distance.
- FIG. 3 a hexagonal first Brillouin region is obtained.
- FIG. 3 shows a latticeless band structure in a uniform medium obtained in the region surrounded by the symmetry point
- FIG. 5 shows a photonic band (PB) structure of the photonic crystal.
- each PB from the first order to the seventh order is a scattered wave of the wave vector k + G.
- each PB is created by rearranging the eigenvalues from the lowest energy, and therefore does not necessarily match the wave vector of the latticeless photonic band.
- the solution is hexafold degenerate at the ⁇ point in the latticeless state of FIG. 4, but the degeneracy is solved at the ⁇ point in the photonic crystal structure of FIG. 5, and six waves create a standing wave.
- double degeneracy is solved at point M, two waves are standing waves, and triple wave is solved at point K to create three waves.
- FIG. 13 is a flowchart showing a calculation flow by computer simulation according to the present embodiment.
- Step S1 In step S1, R / a (R: diameter, a: period) is changed, for example, in 0.01 steps within a range of 0.18 ⁇ R / a ⁇ 0.40.
- Step S2 Since the scattered wave that satisfies the Bragg condition corresponds to one of the photonic bands (PB), the period a that transmits the design wavelength ⁇ is related by the Bragg equation.
- the focused photonic band is a scattered wave (k + G) that satisfies the Bragg condition.
- n av 1.79.
- Step S3 dielectric constants ⁇ 1 and ⁇ 2 are obtained from the determined R / a, wavelength ⁇ , and refractive indexes n 1 and n 2 to obtain a photonic band (PB) structure of TM light by a plane wave expansion method.
- the photonic band gaps (PBGs) between 1 st PB-2 nd PB, 3 rd PB-4 th PB, and 5 th PB-6 th PB are PBG1, PBG2, and PBG3, respectively.
- the relationship is shown in FIG.
- the reason for selecting the second photonic band (2 nd PB) and the fourth photonic band (4 th PB) is that PBG1 and PBG2 are 0.18 ⁇ R / a ⁇ 0.40 as shown in FIG. This is because the second photonic band (2 nd PB) and the fourth photonic band (4 th PB) generate standing waves at each symmetry point, and then change the light propagation direction.
- FIG. 9A shows the photonic band structure of the wavelength in vacuum ⁇ 3 (order) and wave number regarding the second photonic band (2 nd PB).
- a standing wave does not occur at any R / a where 0.18 ⁇ R / a ⁇ 0.40.
- the phase is increased in proportion to the order, and the phase becomes the same at R / a, and a standing wave is generated. As shown in FIG.
- the fourth photonic bands (4 th PB) of all R / a obtained in step S4 are obtained.
- FIG. 9B Multiplied by 4 integers is shown in FIG. 9B, and multiplied by 5 integers is shown in FIG. 9C.
- ⁇ point not applicable
- M point (R / a 0.18)
- K point (R / a 0.27)
- FIG. 10A shows a photonic band structure of wavelength and wave number in vacuum for the second photonic band (2 nd PB).
- K point (R / a 0.26).
- FDTD method finite time domain difference method
- Fig. 11 shows the calculation model.
- the flip chip structure is composed of an Al reflective film, ITO transparent electrode, p-GaN layer, light emitting layer, n-GaN layer, and GaN substrate.
- the light emitted from the light emitting layer is emitted to the outside mainly from the back surface or side wall of the GaN substrate.
- the center wavelength is 455 nm and the degree of polarization is 0.94.
- the radiation pattern for verifying the light distribution is calculated in the far field.
- E total
- This electric field strength is proportional to the light intensity. Therefore it is possible to obtain the radiation pattern by calculating at 5 ° intervals in a range of electric field intensity in this respect P 1 of 0 ° ⁇ ⁇ ⁇ 180 °, 0 ° ⁇ ⁇ ⁇ 360 °.
- the LEE increase / decrease rate (Far Field @ 455 nm) refers to the increase / decrease rate of LED elements at a wavelength of 455 nm calculated in the far field.
- the LEE increase / decrease rate (Near Field @ 455 nm) refers to the increase / decrease rate of the LED element at the wavelength of 455 nm calculated in the near field.
- the photonic band (PB) state is the symmetry point of the second photonic band (2 nd PB) and the fourth photonic band (4 th PB) that are candidates for photonic crystal optimization obtained in steps 3 to 6 The state in is shown.
- the radiation pattern angle distribution in each order m is shown in FIGS.
- the intensity of light in each area element on the polar coordinates is expressed by sin ⁇ d ⁇ d ⁇ .
- the intensity on the vertical axis is displayed as a relative output per unit area.
- the output at the angle ⁇ is displayed by integrating all ⁇ in the range of 0 ° ⁇ ⁇ ⁇ 360 °.
- Step S8 The R / a and the order m corresponding to the target light distribution are selected from the R / a and the order m with a large light extraction efficiency (LEE) increase / decrease rate. Therefore, the diameter, period, and depth, which are parameters for optimizing the photonic crystal, are determined.
- R / a that is a candidate for photonic crystal optimization obtained in steps S3 to S6 is compared with R / a other than the candidate in the range of 0.18 ⁇ R / a ⁇ 0.40. As a result, the R / a optimization candidates obtained in steps S3 to S6 are settled.
- R / a which is a candidate for photonic crystal optimization, has a good light extraction efficiency and light distribution compared to other R / a and micron patterns.
- determining the structure of an optical semiconductor device to be actually manufactured it can be determined based on an optimized value, but a structure using a value close to this value can be used without using the optimized value itself. It is within the scope of the invention.
- the state of TE light incident on the photonic crystal is also considered below.
- the electric field of TE light tends to stay between the pillar structure rods in parallel in the photonic crystal plane, and when the average refractive index n av , period a and design wavelength ⁇ satisfy the Bragg condition, the electric field plane Reflected by Bragg diffraction.
- the physical properties of the photonic crystal by TE light are analyzed by obtaining the photonic band (PB) structure from the following Maxwell equations by the same steps (steps S1 to S3) as the TM light.
- ⁇ relative dielectric constant
- G reciprocal lattice vector
- k wave number
- ⁇ frequency
- c speed of light
- H magnetic field.
- PBGs photonic band gaps between 1 st PB-2 nd PB, 3 rd PB-4 th PB, 5 th PB-6 th PB, 7 th PB-8 th PB are PBG1, PBG2, PBG3 and PBG4 are shown, and the relationship between R / a and PBG is shown in FIG.
- PBG1 and PBG2 do not exist in TE light. Therefore, in these photonic bands, there is no standing wave and the TE light reflection effect is weakened.
- PBG3 is present at 0.28 ⁇ R / a ⁇ 0.39, but its size is very small compared to the PBG of TM light.
- PBG4 is 0.20 ⁇ R / a ⁇ 0.25 and PBG is present, but the size is also very small.
- the optimization candidate R / a obtained by analysis of TE light is reflected inside the LED by the photonic crystal, but the reflection effect is TM because the size of each PBG is small and the energy to generate a standing wave is small. Weak compared to the light transmission effect.
- the degree of polarization of the light source is set to 0.94 in the FDTD analysis according to the present embodiment.
- TE light has an intensity of 10 times or more that of TM light, and generally a photonic crystal (hole) advantageous to TE light is often formed.
- the rate of increase / decrease in the light extraction efficiency of the photonic crystal (pillar) is very effective, and the structure of the photonic crystal is designed according to the processing location of the light extraction surface regardless of TE light or TM light. It suggests the importance of things.
- Nanoimprinting has an excellent technique for transferring a photonic crystal pattern of a mold in a large area to an organic resist spin-coated on a substrate. Also, if a resin film mold is used, transfer is possible even if the substrate is warped by several hundred microns.
- the organic imprinting resist for nanoimprinting does not necessarily have a sufficient etching selectivity with respect to the material that is the pattern formation portion in order to emphasize fluidity. Further, the pattern size of the mold does not match the pattern formation portion size after etching. In order to solve this problem, a process using a two-layer resist is performed as follows.
- FIG. 27 shows a photonic crystal periodic structure having a fine pattern on the order of nanometers using a transfer technique based on a nanoimprint lithography method using a two-layer resist having both characteristics of fluidity and etching selectivity. As an example, it was transferred to the back surface of the GaN substrate.
- a laminated structure having a design wavelength of ⁇ and containing at least the Al reflective electrode 1, the p-type GaN layer 5, and the p-type GaN light emitting layer 7 in this order from the side opposite to the surface of the GaN substrate 15 is prepared.
- a mold for forming the photonic crystal periodic structure 17 on the opposite side of the GaN substrate 15 from the Al reflective electrode 1 is prepared, a resist layer is formed on the surface of the GaN substrate 15, and the mold structure is transferred. Then, the photonic crystal periodic structure 17 is formed by etching from the surface of the GaN substrate 15 using the resist layer as a mask. This will be described below with reference to FIG.
- a mold for accurately reproducing a periodic structure optimized by the implementation of the present invention on a GaN substrate is created.
- a resin mold can be used so as to follow the warping of the substrate as shown in FIG.
- an organic lower layer resist having a large etching selectivity is spin-coated on the GaN substrate with a thickness g.
- the thickness g is selectively determined according to the etching selectivity of the lower layer resist with respect to the GaN substrate.
- a silicon-containing upper layer resist having fluidity and oxygen resistance function is spin-coated at a predetermined thickness on the lower resist surface (FIG. 27A).
- the mold pattern is transferred to the upper layer resist using a nanoimprint apparatus (FIG. 27B).
- the organic lower resist is etched with oxygen plasma to form a pattern mask for dry etching the GaN substrate (FIG. 27D).
- the diameter d 1 on the GaN substrate side of the pattern mask shown in FIG. 27E can be finely adjusted within a range of about 30% of d 1 by adjusting the oxygen plasma conditions.
- Optimized periodic structure is formed by dry-etching the GaN substrate with ICP plasma through a pattern mask (FIG. 27 (e)).
- the shape after etching is a trapezoidal shape of d 1 ⁇ d 2 as shown in FIG. 27F, and the side wall angle depends on the etching selectivity of the organic lower layer resist.
- the thickness g of the organic underlayer resist is changed, the depth of the photonic crystal periodic structure formed on the GaN substrate after dry etching can be easily changed with respect to the depth of the mold.
- the depth can be about 1.5 times.
- the diameter of the periodic structure can be easily changed about 30%. This can be replaced by remanufacturing the mold, which contributes to a reduction in the manufacturing time and cost of the mold, and is a great merit in terms of the manufacturing cost of the semiconductor light emitting device.
- Processing and control can be realized by software processing by CPU (Central Processing Unit) or GPU (Graphics Processing Unit), ASIC (Application Specific Integrated Circuit) or FPGA (Field Programmable Hardware) that can be realized by ProgrammableGardware.
- CPU Central Processing Unit
- GPU Graphics Processing Unit
- ASIC Application Specific Integrated Circuit
- FPGA Field Programmable Hardware
- Each component of the present invention can be arbitrarily selected, and an invention having a selected configuration is also included in the present invention.
- a program for realizing the functions described in the present embodiment is recorded on a computer-readable recording medium, and the program recorded on the recording medium is read into a computer system and executed to execute processing of each unit. May be performed.
- the “computer system” here includes an OS and hardware such as peripheral devices.
- the “computer system” includes a homepage providing environment (or display environment) if a WWW system is used.
- the “computer-readable recording medium” means a storage device such as a flexible disk, a magneto-optical disk, a portable medium such as a ROM and a CD-ROM, and a hard disk incorporated in a computer system. Furthermore, the “computer-readable recording medium” dynamically holds a program for a short time like a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line. In this case, a volatile memory in a computer system serving as a server or a client in that case, and a program that holds a program for a certain period of time are also included.
- the program may be a program for realizing a part of the above-described functions, and may be a program that can realize the above-described functions in combination with a program already recorded in the computer system. At least a part of the functions may be realized by hardware such as an integrated circuit.
- the present invention can be used as a semiconductor light emitting device.
- a period of the photonic crystal periodic structure
- R radius of the periodic structure
- h processing depth of the periodic structure
- 1 Al reflective electrode (film)
- 3 ITO transparent electrode
- 7 Light emitting layer
- 17b air
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- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- Led Devices (AREA)
Abstract
L'invention concerne un élément électroluminescent à semi-conducteur doté d'un film réfléchissant disposé sur une surface (côté) avant d'un substrat en GaN et d'une structure périodique de cristal photonique disposée sur une surface (côté) arrière du substrat en GaN, la structure périodique de cristal photonique étant telle que la longueur d'onde nominale λV dans le vide, une période a en tant que paramètre de la structure périodique et un rayon R satisfont la condition de Bragg, une structure de bande photonique de lumière de TM présentant, dans une gamme de R/a allant de 0,18 à 0,40, deux bandes interdites photoniques à l'intérieur de la quatrième bande photonique.
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JP2014248769 | 2014-12-09 | ||
JP2014-248769 | 2014-12-09 |
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WO2016093257A1 true WO2016093257A1 (fr) | 2016-06-16 |
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PCT/JP2015/084461 WO2016093257A1 (fr) | 2014-12-09 | 2015-12-09 | Élément électroluminescent et procédé pour sa fabrication |
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WO (1) | WO2016093257A1 (fr) |
Cited By (2)
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JPWO2019146737A1 (ja) * | 2018-01-26 | 2021-01-07 | 丸文株式会社 | 深紫外led及びその製造方法 |
CN116169200A (zh) * | 2023-04-26 | 2023-05-26 | 北京心灵方舟科技发展有限公司 | 一种近红外敏感硅光电倍增管及其制作工艺方法 |
Families Citing this family (1)
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FR3068173B1 (fr) * | 2017-06-27 | 2020-05-15 | Aledia | Dispositif optoelectronique |
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Cited By (2)
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JPWO2019146737A1 (ja) * | 2018-01-26 | 2021-01-07 | 丸文株式会社 | 深紫外led及びその製造方法 |
CN116169200A (zh) * | 2023-04-26 | 2023-05-26 | 北京心灵方舟科技发展有限公司 | 一种近红外敏感硅光电倍增管及其制作工艺方法 |
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TW201633559A (zh) | 2016-09-16 |
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