USRE42007E1 - Vertical geometry InGaN LED - Google Patents

Vertical geometry InGaN LED Download PDF

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USRE42007E1
USRE42007E1 US12/108,604 US10860408A USRE42007E US RE42007 E1 USRE42007 E1 US RE42007E1 US 10860408 A US10860408 A US 10860408A US RE42007 E USRE42007 E US RE42007E
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gallium nitride
layer
light emitting
emitting diode
undoped
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Kathleen Marie Doverspike
John Adam Edmond
Hua-Shuang Kong
Heidi Marie Dieringer
David B. Slater, Jr.
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Cree Inc
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    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L33/00Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L33/0004Devices characterised by their operation
    • H01L33/002Devices characterised by their operation having heterojunctions or graded gap
    • H01L33/0025Devices characterised by their operation having heterojunctions or graded gap comprising only AIIIBV compounds
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L33/00Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L33/005Processes
    • H01L33/0062Processes for devices with an active region comprising only III-V compounds
    • H01L33/0066Processes for devices with an active region comprising only III-V compounds with a substrate not being a III-V compound
    • H01L33/007Processes for devices with an active region comprising only III-V compounds with a substrate not being a III-V compound comprising nitride compounds
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L33/00Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L33/02Semiconductor devices with at least one potential-jump barrier or surface barrier 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
    • H01L33/26Materials of the light emitting region
    • H01L33/30Materials of the light emitting region containing only elements of group III and group V of the periodic system
    • H01L33/32Materials of the light emitting region containing only elements of group III and group V of the periodic system containing nitrogen
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L33/00Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L33/02Semiconductor devices with at least one potential-jump barrier or surface barrier 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
    • H01L33/12Semiconductor devices with at least one potential-jump barrier or surface barrier 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 stress relaxation structure, e.g. buffer layer

Abstract

A vertical geometry light emitting diode is disclosed that is capable of emitting light in the red, green, blue, violet and ultraviolet portions of the electromagnetic spectrum. The light emitting diode includes a conductive silicon carbide substrate, an InGaN quantum well, a conductive buffer layer between the substrate and the quantum well, a respective undoped gallium nitride layer on each surface of the quantum well, and ohmic contacts in a vertical geometry orientation.

Description

This is a continuation of Ser. No. 09/154,363 filed Sep. 16, 1998, U.S. Pat. No. 6,459,100.

The development of this invention included support from DARPA under contracts MDA972-95-C-0016 and F19628-96-C-0066. The government may have certain rights in this invention.

FIELD OF THE INVENTION

This invention relates to light emitting diodes (LEDs) formed from Group III nitrides (i.e., Group III of the Periodic Table of the Elements), and in particular relates to LEDs that incorporate indium gallium nitride (InGaN) quantum wells as the active portion to produce output in the red to ultraviolet portions, and particularly the green to ultraviolet portions, of the electromagnetic spectrum.

BACKGROUND OF THE INVENTION

Light emitting diodes (“LEDs”) are p-n junction devices that have been found to be useful in various roles as the field of optoelectronics has grown and expanded over the years. Devices that emit in the visible portion of the electromagnetic spectrum have been used as simple status indicators, dynamic power level bar graphs, and alphanumeric displays in many applications, such as audio systems, automobiles, household electronics, and computer systems, among many others. Infrared devices have been used in conjunction with spectrally matched phototransistors in optoisolators, handheld remote controllers, and interruptive, reflective, and fiber-optic sensing applications.

An LED operates based on the recombination of electrons and holes in a semiconductor. When an electron carrier in the conduction band combines with a hole in the valence band, it loses energy equal to the bandgap in the form of an emitted photon; i.e., light. The number of recombination events under equilibrium conditions is insufficient for practical applications but can be enhanced by increasing the minority carrier density.

In an LED, the minority carrier density is conventionally increased by forward biasing the diode. The injected minority carriers radiatively recombine with the majority carriers within a few diffusion lengths of the junction edge. Each recombination event produces electromagnetic radiation, i.e., a photon. Because the energy loss is related to the bandgap of the semiconductor material, the bandgap characteristics of the LED material have been recognized as being important.

As with other electronic devices, however, there exists both the desire and the need for more efficient LEDs, and in particular, LEDs that will operate at higher intensity while using less power. Higher intensity LEDs, for example, are particularly useful for displays or status indicators in various high ambient environments. There also is a relation between intensity output of the LED and the power required to drive the LED. Low power LEDs, for example, are particularly useful in various portable electronic equipment applications. An example of an attempt to meet this need for higher intensity, lower power, and more efficient LEDs may be seen with the development of the AlGaAs LED technology for LEDs in the red portions of the visible spectrum. A similar continual need has been felt for LEDs that will emit in the green, blue and ultraviolet regions of the visible spectrum. For example, because blue is a primary color, its presence is either desired or even necessary to produce full color displays or pure white light.

The common assignee of the present patent application was the first in this field to successfully develop commercially viable LEDs available in large quantities and that emitted light in the blue color spectrum. These LEDs were formed in silicon carbide; and examples are described in U.S. Pat. Nos. 4,918,497 and 5,027,168 to Edmond each titled “Blue Light Emitting Diode Formed in Silicon Carbide.”

Other examples of such a blue LED are described in U.S. Pat. No. 5,306,662 to Nakamura et al. titled “Method of Manufacturing P-Type Compound Semiconductor” and U.S. Pat. No. 5,290,393 to Nakamura titled “Crystal Growth Method for Gallium Nitride-Based Compound Semiconductor.” U.S. Pat. No. 5,273,933 to Hatano et al. titled “Vapor Phase Growth Method of Forming Film in Process of Manufacturing Semiconductor Device” also describes LEDs formed of GaInAlN on SiC substrates and Zinc Selenide (ZnSe) on gallium arsenide (GaAs) substrates.

General discussions of LED technology can be found at Dorf, The Electrical Engineering Handbook, 2d Ed. (1997, CRC Press), at pages 1915-1925, section 83.1, “Light Emitting Diodes,” and in Sze, Physics of Semiconductor Devices, at pages 681 ff, Chapter 12, “LED and Semiconductor Lasers” (1981, John Wiley & Sons, Inc.).

As known to those familiar with photonic devices such as LEDs, the frequency of electromagnetic radiation (i.e., the photons) that can be produced by a given semiconductor material are a function of the material's bandgap. Smaller bandgaps produce lower energy, longer wavelength photons, while wider bandgap materials are required to produce higher energy, shorter wavelength photons. For example, one semiconductor commonly used for lasers is indium gallium aluminum phosphide (InGaAlP). Because of this material's bandgap (actually a range of bandgaps depending upon the mole or atomic fraction of each element present), the light that InGaAlP can produce is limited to the red portion of the visible spectrum, i.e., about 600 to 700 nanometers (nm).

Working backwards, in order to produce photons that have wavelengths in the blue or ultraviolet portions of the spectrum, semiconductor materials are required that have relatively large bandgaps. Typical candidate materials include silicon carbide (SiC) and Group III nitrides, particularly gallium nitride (GaN), and ternary and tertiary Group III nitrides such as aluminum gallium nitride (AlGaN), indium gallium nitride (InGaN), and aluminum indium gallium nitride (AlInGaN).

Shorter wavelength LEDs offer a number of advantages in addition to color. In particular, when used in optical storage and memory devices (e.g., “CD-ROM” or “optical disks”), their shorter wavelengths enable such storage devices to hold proportionally more information. For example, an optical device storing information using blue light can hold approximately 4 times as much information as one using red light, in the same space.

The Group III nitrides, however, are attractive LED candidate material for green, blue, and UV frequencies because of their relatively high bandgaps (i.e., GaN is 3.36 eV at room temperature) and because they are direct bandgap materials rather than an indirect bandgap material. As known to those familiar with semiconductor characteristics, a direct bandgap material is one in which an electron's transition from the valence band to the conduction band does not require a change in crystal momentum for the electron. In indirect semiconductors, the alternative situation exists; i.e., a change of crystal momentum is required for an electron's transition between the valence and conduction bands. Silicon and silicon carbide are examples of such indirect semiconductors.

Generally speaking, LEDs formed in direct bandgap materials will perform more efficiently than ones formed in indirect bandgap materials because the photon from the direct transition retains more energy than one from an indirect transition.

The Group III nitrides suffer from a different disadvantage, however: the failure to date of any workable technique for producing bulk single crystals of Group III nitrides which could form appropriate substrates for Group III nitride photonic devices. As is known to those familiar with semiconductor devices, they all require some sort of structural substrate. Typically, a substrate formed of the same materials as the active region of a device offers significant advantages, particularly in crystal growth and matching. Because Group III nitrides have yet to be formed in such bulk crystals, however, Group III nitride photonic devices must be formed in epitaxial layers on different—i.e., other than Group III nitride—substrates.

Using different substrates, however, causes an additional set of problems, mostly in the areas of crystal lattice matching and thermal coefficients of expansion (TCEs). In almost all cases, different materials have different crystal lattice parameters and TCEs. As a result, when Group III nitride epitaxial layers are grown on a different substrate, some crystal mismatch will occur, and the resulting epitaxial layer is referred to as being either “strained” or “compressed” by these mismatches. Such mismatches, and the strain they produce, carry with them the potential for crystal defects which in turn affect the electronic characteristics of the crystals and the junctions, and thus correspondingly tend to degrade or even prevent the performance of the photonic device. Such defects are even more problematic in higher power structures.

To date, a common substrate for Group III nitride devices has been sapphire; i.e., aluminum oxide (Al2O3). Sapphire is optically transparent in the visible and UV ranges, but is unfortunately insulating rather than conductive, and carries a lattice mismatch with (for example) gallium nitride of about 16%. In the absence of a conductive substrate, “vertical” devices (those with contacts on opposite sides) cannot be formed, thus complicating the manufacture and use of the devices.

As a particular disadvantage, horizontal structures (those with contacts on the same side of the device), such as those required when Group III nitride layers are formed on sapphire, also produce a horizontal flow of current and therefore the current density through the layer is substantially increased. This horizontal current flow puts an additional strain on the already-strained (e.g., a 16% lattice mismatch between GaN and sapphire) structure and accelerates the degradation of the junction and the device as a whole.

Gallium nitride also carries a lattice mismatch of about 2.4% with aluminum nitride (AlN) and a 3.5% mismatch with silicon carbide. Silicon carbide has a somewhat lesser mismatch (only about 1%) with aluminum nitride.

OBJECT AND SUMMARY OF THE INVENTION

Therefore, it is an object of the present invention to provide an improved brightness light emitting diode that takes advantage of the light emitting characteristics of indium gallium nitride along with the advantages of silicon carbide substrate.

The invention meets this object with a vertical geometry light emitting diode that is capable of emitting light in the red, green, blue, violet, and ultraviolet portions of the electromagnetic spectrum. The light emitting diode comprises a conductive silicon carbide substrate, an indium gallium nitride quantum well, a conductive buffer layer between the substrate and the quantum well, respective undoped gallium nitride layer on each surface of the quantum well, and ohmic contacts to the device in a vertical geometry orientation.

In another aspect, the invention is a vertical geometry light emitting diode formed of an n-type silicon carbide substrate, a conductive buffer layer on the substrate, a first layer of gallium nitride on the conductive buffer layer that is n-type, a second layer of gallium nitride on the first gallium nitride layer that is undoped, an indium gallium nitride quantum well on the second gallium nitride layer, a third layer of gallium nitride on the quantum well that is undoped, a first layer of aluminum gallium nitride on the third gallium nitride layer that is undoped, a second layer of aluminum gallium nitride that is p-type on the first aluminum gallium nitride layer, a fourth gallium nitride layer that is p-type on the second aluminum gallium nitride layer, an ohmic contact to the substrate, and an ohmic contact to the fourth gallium nitride layer.

The foregoing and other objects and advantages of the invention will become clearer when taken in conjunction with the detailed description and the accompanying drawings in which:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional diagram of a light emitting diode according to the present invention;

FIG. 2 is a comparative plot of the quantum efficiency of diodes according to the present invention and those of prior devices;

FIG. 3 is a plot of dominant wavelength versus forward current and comparing light emitting diodes of the present invention with those formed on sapphire substrates;

FIG. 4 is a plot of the full width at half maximum versus wavelength for diodes according to the present invention compared to those formed on sapphire; and

FIGS. 5 and 6 are plots of the current versus voltage characteristics of two diodes according to the present invention.

DETAILED DESCRIPTION

The present invention is a vertical geometry light emitting diode that is capable of emitting light in the red, green, blue, violet, and ultraviolet portions of the electromagnetic spectrum. As used herein, the phrase “vertical geometry” refers to the characteristic in which ohmic contacts to a device can be placed on opposite surfaces of the structure. Such geometry allows appropriate metal contacts and wire leads (including wire leads in microprocessors and printed circuits) to be more easily made to the device, as opposed to those in which the anode and cathode must be placed on the same surface of the device. FIG. 1 illustrates the device broadly designated at 10, which in its broadest aspects comprises the conductive silicon carbide substrate 11, an indium gallium nitride quantum well 12, a conductive buffer layer 13 between the substrate 11 and the quantum well 12, respective undoped gallium nitride layers 14 and 15 on each surface of the quantum well 12, and ohmic contacts 16 and 17 in a vertical geometry orientation.

The silicon carbide substrate 11 is preferably selected from among the 3C, 4H, 6H, and 15R polytypes, and most preferably is the 6H polytype. The substrate is most preferably formed according to the growth techniques set forth in commonly assigned (or licensed) U.S. Pat. No. Re. 34,861 (U.S. Pat. No. 4,866,005), the contents of which are incorporated entirely herein by reference.

The conductive buffer 13 is preferably formed to have the structure, and incorporating the methods, set forth in co-pending and commonly assigned pending U.S. application Ser. No. 08/944,547, filed Oct. 7, 1997, for “Group III Nitride Photonic Devices on Silicon Carbide Substrates with Conductive Buffer Interlayer Structure,” the contents of which are incorporated entirely herein by reference.

As noted above, a silicon carbide substrate has a better lattice match with Group III nitrides than does sapphire. Furthermore, Group III nitrides are in tension on silicon carbide whereas they are in compression on sapphire. As used in this art, “tension” refers to the relationship in which the coefficient of thermal expansion of an epitaxial layer is higher than that of its substrate. “Compression” refers to the alternative relationship in which the coefficient of thermal expansion of an epitaxial layer is lower than that of its substrate. As between Group III nitride layers and silicon carbide substrates, the differences in the lattice constants (those of the nitrides are higher than those of silicon carbide) add to the compression, but the overall tension tends to be dominated by the respective coefficients of thermal expansion. In this regard, there are almost no reports of InGaN growth on an epilayer that is under tension.

As known to those familiar with electronic structures, a quantum well is typically formed of one or several thin layers of a semiconductive material that has active layers that are very thin. In particular, when the thickness of the active layer is reduced to the order of the deBroglie wavelength of the carrier, the result is a series of discrete energy levels that have the bound state energies of a finite square well. See, Sze Physics of Semiconductor Devices, 2d Ed. (1981) at pp. 127 and 729. As recognized by those familiar with such structures, the use of single or multiple quantum wells increases the electron density in the desired transitions and thus produces increased brightness in the resulting emissions.

Taken in more detail, the silicon carbide substrate 11 is n-type, and a first layer of n-type gallium nitride 20, typically doped with silicon, is on the conductive buffer layer 13 and borders the (second) undoped layer of gallium nitride 14 referred to above.

The preferred structure also includes a first layer of undoped aluminum gallium nitride 21 on the other undoped gallium nitride layer 15 which is the third gallium nitride layer overall. The second layer of aluminum gallium nitride 22 that is p-type (preferably doped with magnesium) is on the first undoped layer 21. A p-type gallium nitride layer 23, the fourth gallium nitride layer overall, completes the device and is preferably doped with magnesium. As FIG. 1 illustrates, an ohmic contact 16 is made to the conductive silicon carbide substrate and another ohmic contact 17 is made to the p-type gallium nitride layer 23. In preferred embodiments, the ohmic contact 16 to the substrate 11 comprises nickel (Ni) and the ohmic contact 17 to the p-type gallium nitride layer 23 is formed of platinum (Pt). Other metals can be used for the ohmic contacts provided, of course, that they have the appropriate ohmic characteristics with respect to the layers they contact, and that they provide an appropriate chemical and physical attachment to the respective layers.

In preferred embodiments, the indium gallium nitride quantum well 12 is intrinsically n-type, and can comprise a single (SQW) or a multiple quantum well (MQW).

Each of the layers offers particular advantages in the overall structure of the invention. As noted above, the n-type silicon carbide substrate has a much higher thermal conductivity than sapphire, provides a much better lattice match with Group III nitrides than does sapphire, and its conductive characteristics make it ideal for a vertical device.

The conductive buffer layer 13 serves the purposes set forth in co-pending application Ser. No. 08/944,547, filed Oct. 7, 1997, as referred to and incorporated above. In its basic function, the conductive buffer layer 13 provides an advantageous crystal transition from the silicon carbide substrate to the gallium nitride layers 20 and 14, and its conductive characteristics complement and enable the vertical geometry of the device.

The first gallium nitride layer 20, together with the conductive buffer 13, have a total thickness of about 1.8 microns. The conductive buffer layer 13 and the gallium nitride layer 20 are preferably grown under a hydrogen (H2) atmosphere at a temperature of about 1040° C. in preferred circumstances. The n-type gallium nitride layer 20 should be thick enough to minimize defects propagated from the interface between the silicon carbide substrate 11 and the conductive buffer 13, and to planarize the overall surface. If the layer is too thin, it empirically appears to affect the wavelength uniformity of the device.

The undoped gallium nitride layer 14, which in the preferred embodiment is the second gallium nitride layer overall, has been demonstrated to increase the brightness and the emission uniformity of the device. Although this remains an empirical result to date, and applicants do not wish to be bound by any particular theory, it appears that the undoped gallium nitride layer 14 (which is grown under a nitrogen atmosphere) tends to trap or bury hydrogen so that it does not later affect the InGaN quantum well which must be isolated from nitrogen. The use of the undoped gallium nitride layer 14 also eliminates any growth stop that would otherwise be required because it is grown in the same nitrogen (N2) atmosphere in which the InGaN quantum well is later grown. When a growth stop is scheduled during the manufacture of these types of devices, the interface between the layers grown before and after the stop can tend to degrade.

Alternatively, the undoped gallium nitride layer 14 may simply help release the strain that has been built up between the silicon carbide substrate and the Group III nitride layers thereon. As noted above, the undoped gallium nitride layer 14 is grown under a nitrogen atmosphere (as opposed to the n-type predecessor layer 20 of gallium nitride that was grown under a hydrogen atmosphere) and preferably at temperatures of between about 750° and 800° C. to a total thickness of about 200 angstroms.

The indium gallium nitride quantum well 12 can be a single or multiple quantum wells and is typically grown to a thickness of between about 20 and 30 angstroms at temperatures of between about 750° and 800° C. under the same nitrogen atmosphere as the undoped gallium nitride layer 14. The quantum well is, of course, the active layer of the device and produces the desired output. From a functional standpoint, the quantum well 12 should be “pseudo-morphic” or “metastable”, i.e., thin enough to avoid crystal defects that would tend to appear in thicker layers of the otherwise similar or identical material.

As well known to those familiar with Group III nitrides, the band structure and thus the emission of the quantum well differs depending upon the amount of indium in the ternary compound, see e.g., U.S. Pat. No. 5,684,309 at FIGS. 10 and 11 and Column 7, lines 19-42, which are illustrative, but not limiting, of this characteristic. For blue LEDs, the mole fraction of indium is about 35 percent while for green LEDs the mole fraction of indium is somewhat higher, preferably between about 50 and 55 percent. The devices can thus be designed to emit at specific wavelengths by controlling the mole fraction (or mole percentage) of indium in the ternary InGaN compound. Larger fractions of indium tend to be more unstable than smaller fractions, however, and thus this characteristic is typically considered in selecting a desired or optimum composition for the quantum well(s).

The third overall gallium nitride layer 15 is the other undoped gallium nitride layer bordering the quantum well 12 and serves to protect the InGaN quantum well 12 from any exposure to hydrogen or high temperatures during the crystal growth processes.

The upper undoped gallium nitride layer 15 is likewise grown in a nitrogen atmosphere for the purpose of protecting the quantum well 12 from exposure to hydrogen. Additionally, the gallium nitride layer 15 protects the InGaN quantum well 12 from exposure to high temperatures, it being recognized that at about 950° C. or above, InGaN decomposes.

The undoped aluminum gallium nitride layer 21 has a generally higher crystal quality than doped AlGaN and along with the undoped gallium nitride layer 15 helps protect the InGaN quantum well from exposure to either higher than desired temperatures or exposure to hydrogen. The undoped AlGaN layer 21 is grown in a nitrogen atmosphere.

In general, a hydrogen atmosphere produces higher quality layers of GaN and AlGaN, but affects InGaN detrimentally. Thus, wherever possible, growth is carried out in the hydrogen atmosphere, changing to the nitrogen atmosphere to successfully grow the InGaN quantum well and its adjacent layers.

Both the undoped gallium nitride layer 15 and the undoped aluminum gallium nitride layer 21 are relatively thin. The gallium nitride layer 15 is on the order of 20-30 angstroms and is grown at a temperature of between about 750° and 800° C. The undoped aluminum gallium nitride layer 21 has a thickness of between about 30 and 50 angstroms, and is grown at temperatures of about 800° to 850° C.

The p-type aluminum gallium nitride layer 22 is somewhat thicker, on the order of about 200 angstroms and is grown in a hydrogen atmosphere at temperatures above about 900° C. It provides a high-quality crystal layer to the overall structure and provides the holes that are injected into the quantum well to produce the desired emission. Finally, the p-type gallium nitride contact layer 23 provides a more convenient material for the ohmic contact 17. As known to those familiar with these materials, making an appropriate ohmic contact to aluminum gallium nitride is at least difficult, and in many cases impossible.

The growth gases for the various layers are straightforward. Silane (SiH4) trimethylgallium ((CH3)3Ga) and ammonia (NH3) are used to form the n-type gallium nitride layer 20. Triethylgallium ((C2H5)3Ga) can be used in place of trimethylgallium as may be desired. Similarly, indium and aluminum are provided using trimethylindium ((CH3)3In) or trimethylaluminum ((CH3)3Al) as the source gases. Ammonia is likewise the preferred source gas for the nitrogen for each of the layers.

As noted above, in the preferred embodiments, the conductive buffer layer 13 and the first GaN layer 20 are grown in a hydrogen atmosphere that facilitates their growth and desired characteristics. This growth under H2 is indicated by the arrow 25 in FIG. 1. The second GaN layer 14, the InGaN quantum well 12, the third GaN layer 15, and the first AlGaN layer 21 are then grown under a nitrogen atmosphere and preferably without a growth stop. Finally, the second AlGaN layer 22 and the fourth GaN layer 23 are grown under a hydrogen atmosphere, and again preferably without a growth stop. In this manner, the InGaN quantum well 12 as well as the layers bordering it are all grown without a growth stop, because the changeover from hydrogen to nitrogen atmosphere occurs at the undoped GaN layer 14, and the corresponding changeover from nitrogen back to hydrogen occurs after the undoped AlGaN layer 21. As known to those familiar with crystal growth—and specifically CVD epitaxial growth—techniques, the continuous growth process tends to produce noticeably better interfaces between epitaxial layers than do growth processes that include stops. In this manner, the structure of the LED according to the invention enhances the growth technique and the continuous growth technique enhances the resulting performance of the LED.

In preferred embodiments, the silicon carbide substrate 11 is “back implanted.” As background, temperatures of 930° C. (at least) are required to obtain an ohmic contact on n-type silicon carbide that is typically doped at between about 6E17 and 2E18 in LEDs. Such temperatures do not generally adversely affect gallium nitride, but tend to degrade or destroy the indium gallium nitride quantum well 12. Accordingly, in order to obtain a good ohmic contact to silicon carbide at lower temperatures, the silicon carbide substrate 11 is highly doped on the back side, a technique that enables an appropriate ohmic contact to be formed at temperatures of as low as 800° C. with the expectation being that temperatures as low as 750° C. can similarly be obtained.

The highly doped back side of the silicon carbide substrate 11 is preferably doped by ion implantation, although other techniques such as a laser anneal or even a thin epitaxial layer (which can be impractical under many circumstances) could also be used. By way of example rather than limitation, the silicon carbide substrate 11 is normally doped at about 1.2 E 18 (1.2×1018 cm−3), and the implanted part reaches a concentration of about 1 E 20 (1×10°cm−3).

Accordingly, in another aspect, the invention comprises the method of producing the vertically oriented light emitting diode of the invention. In this aspect, the invention comprises successively growing a conductive buffer layer and an n-type gallium nitride layer in a hydrogen atmosphere on an n-type silicon carbide substrate. Thereafter, successive layers are grown of thin undoped gallium nitride, the indium gallium nitride quantum well, a second thin layer of undoped gallium nitride, and a thin layer of undoped aluminum gallium nitride in a nitrogen atmosphere. The technique is completed by thereafter successively growing a layer of p-type aluminum gallium nitride and a layer of p-type gallium nitride in a hydrogen atmosphere. The ohmic contacts can then be added to the p-type gallium nitride layer and to the silicon carbide substrate with preferred embodiments including the step of increasing the doping of the silicon carbide substrate at the portion where the ohmic contact is added in the manner just described, i.e., preferably by ion implantation. The sources gases are those mentioned above.

As indicated by the source gases, the preferred technique for growth of these layers is chemical vapor deposition (CVD). Such techniques are very well understood in this art. The nature of CVD, and of individual CVD equipment, is nevertheless such that individual gas flow rates, temperatures, reactor pressures, time periods, and other process parameters must generally be determined based upon particular equipment and circumstances. Given the composition of the layers as described herein, including the thicknesses of each layer, and the preferred growth temperature ranges, those of ordinary skill in this art will be able to replicate the disclosed process and the resulting structure without undue experimentation.

FIGS. 2 through 6 illustrate some of the demonstrated advantages of diodes designed and manufactured according to the present invention. FIG. 2 illustrates that the quantum efficiency of LEDs according to the present invention are at least as good as several others formed on sapphire substrates. Furthermore, the vertical device provides a much smaller chip than do equivalent sapphire based devices, while producing the same output. For example, sapphire based devices evaluated for comparative purposes herein (e.g. FIGS. 2, 3, and 4) are 14 mil×14 mil (196 mil2) while those according to the present invention (and providing the same brightness) are 10 mil×10 mil (100 mil2); i.e. only 57 percent as large.

FIG. 3 illustrates that LEDs according to the present invention maintain a more consistent color over a range of forward currents than do devices formed on sapphire. As FIG. 3 shows, the sapphire-based LEDs tend to emit in or near the yellow portion of the spectrum at low forward current (e.g., 544 nm at 2 milliamps) while the LEDs according to the invention remain in the green region (531 nm at 2 mA).

FIG. 4 shows that SiC-based LEDs according to the present invention exhibit narrower emissions (purer colors) at desired wavelengths; i.e., at each measured wavelength, the full width at half maximum (FWHM) for the SiC-based LEDs is at least about 5 nm less than that of the sapphire-based diodes.

FIGS. 5 and 6 show that both green (525 nm) and blue (470 nm) LEDs according to the present invention provide excellent current characteristics under forward bias voltage.

In use, the diodes of the present invention can be used to provide both pixels and displays that incorporate red, green and blue LEDs.

In the drawings and specification, there have been disclosed typical embodiments of the invention, and, although specific terms have been employed, they have been used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention being set forth in the following claims.

Claims (31)

1. A vertical geometry light emitting diode that is capable of emitting light in the electromagnetic spectrum, said light emitting diode comprising:
a conductive silicon carbide substrate;
an InGaN quantum well;
a conductive buffer layer between said substrate and said quantum well;
a respective first undoped gallium nitride layer on each a first surface of said quantum well;
a second layer consisting of undoped gallium nitride on a second surface of said quantum well opposite said first surface; and
ohmic contacts in a vertical geometry orientation;
a doped layer of gallium nitride between said buffer and said undoped gallium nitride layer;
an undoped layer of aluminum gallium nitride on the surface of said second undoped gallium nitride layer on said quantum well that is opposite from said substrate and buffer ; and
a doped layer of aluminum gallium nitride on said undoped aluminum gallium nitride layer.
2. A vertical geometry light emitting diode according to claim 1 and further comprising a doped gallium nitride layer on said doped aluminum gallium nitride layer.
3. A vertical geometry light emitting diode according to claim 2 wherein:
said substrate, said buffer layer and said first undoped gallium nitride layer adjacent said buffer are all is n-type; and
said doped layer of aluminum gallium nitride and doped layer of gallium nitride thereon are is p-type.
4. A vertical geometry light emitting diode according to claim 1 wherein said quantum well comprises a multiple quantum well.
5. A pixel that includes a light emitting diode according to claim 1. A light emitting diode according to claim 1 further comprising:
a conductive silicon carbide substrate; and
a conductive buffer layer between said substrate and said quantum well.
6. A display that includes a plurality of pixels according to claim 5. A light emitting diode according to claim 1 further comprising:
an ohmic contact on one surface of said light emitting diode; and
another ohmic contact on the opposite surface of said light emitting diode and with said ohmic contacts in a vertical geometry orientation.
7. A vertical geometry light emitting diode that is capable of emitting light in the electromagnetic spectrum, said light emitting diode comprising:
an InGaN quantum well;
a respective layer consisting of undoped gallium nitride on each surface of said quantum well;
ohmic contacts in a vertical geometry orientation; a doped layer of gallium nitride below one of said undoped gallium nitride layers;
an undoped layer of aluminum gallium nitride on the surface of the opposite undoped gallium nitride layer; and
a doped layer of aluminum gallium nitride on said undoped aluminum gallium nitride layer.
8. A light emitting diode according to claim 7 and further comprising:
a conductive silicon carbide substrate; and
a conductive buffer layer between said substrate and said quantum well, with said doped gallium nitride layer on said buffer layer.
9. A light emitting diode according to claim 7 comprising a doped gallium nitride layer on said doped aluminum gallium nitride layer.
10. A light emitting diode according to claim 7 wherein:
said opposite undoped gallium nitride layer is n-type; and
said doped layer of aluminum gallium nitride is p-type.
11. A light emitting diode according to claim 7 wherein said quantum well comprises multiple quantum wells.
12. A light emitting diode that is capable of emitting light in the electromagnetic spectrum, said light emitting diode comprising:
a substrate;
an InGaN quantum well;
a buffer layer between said substrate and said quantum well;
a first undoped gallium nitride layer on a first surface of said quantum well;
a second layer consisting of undoped gallium nitride on a second surface of said quantum well opposite said first surface; and
a doped layer of gallium nitride between said buffer and said first undoped gallium nitride layer;
an undoped layer of aluminum gallium nitride on the surface of said second undoped gallium nitride layer on said quantum well that is opposite from said substrate and buffer; and
a doped layer of aluminum gallium nitride on said undoped aluminum gallium nitride layer.
13. A light emitting diode according to claim 12 further comprising:
an ohmic contact on one surface of said light emitting diode; and
another ohmic contact on the opposite surface of said light emitting diode and with said ohmic contacts in a vertical geometry orientation.
14. A light emitting diode according to claim 13 and further comprising:
a conductive silicon carbide substrate; and
a conductive buffer layer between said substrate and said quantum well, with said doped gallium nitride layer on said buffer layer.
15. A light emitting diode that is capable of emitting light in the electromagnetic spectrum, said light emitting diode comprising:
a substrate;
an InGaN quantum well;
a buffer layer between said substrate and said quantum well;
a first undoped gallium nitride layer on a first surface of said quantum well;
a second layer consisting of undoped gallium nitride on a second surface of said quantum well opposite said first surface;
ohmic contacts in a vertical geometry orientation;
a doped layer of gallium nitride between said buffer and said first undoped gallium nitride layer;
an undoped layer of aluminum gallium nitride on the surface of said second undoped gallium nitride layer on said quantum well that is opposite from said substrate and buffer; and
a doped layer of aluminum gallium nitride on said undoped aluminum gallium nitride layer.
16. A light emitting diode according to claim 15 further comprising:
an ohmic contact on one surface of said light emitting diode; and
another ohmic contact on the opposite surface of said light emitting diode and with said ohmic contacts in a vertical geometry orientation.
17. A light emitting diode according to claim 16 and further comprising:
a conductive silicon carbide substrate; and
a conductive buffer layer between said substrate and said quantum well, with said doped gallium nitride layer on said buffer layer.
18. A light emitting diode that is capable of emitting light in the electromagnetic spectrum, said light emitting diode comprising:
an InGaN quantum well;
a first undoped gallium nitride layer on a first surface of said quantum well;
a second undoped gallium nitride layer directly on a second surface of said quantum well opposite said first surface;
an undoped layer of aluminum gallium nitride directly on the surface of said second undoped gallium nitride layer; and
a doped layer of aluminum gallium nitride on said undoped aluminum gallium nitride layer.
19. A light emitting diode according to claim 18 comprising a doped gallium nitride layer on said doped aluminum gallium nitride layer.
20. A light emitting diode according to claim 18 wherein said first undoped gallium nitride layer is n-type and said doped layer of aluminum gallium nitride is p-type.
21. A light emitting diode according to claim 18 wherein said quantum well comprises multiple quantum wells.
22. A light emitting diode according to claim 18 further comprising:
an ohmic contact on one surface of said light emitting diode; and
another ohmic contact on the opposite surface of said light emitting diode and with said ohmic contacts in a vertical geometry orientation.
23. A vertical geometry light emitting diode that is capable of emitting light in the electromagnetic spectrum, said light emitting diode comprising:
an InGaN quantum well;
a respective undoped gallium nitride layer directly on each surface of said quantum well;
ohmic contacts in a vertical geometry orientation;
a doped layer of gallium nitride below one of said undoped gallium nitride layers;
an undoped layer of aluminum gallium nitride directly on the surface of the opposite undoped gallium nitride layer; and
a doped layer of aluminum gallium nitride on said undoped aluminum gallium nitride layer.
24. A light emitting diode according to claim 23 comprising a doped gallium nitride layer on said doped aluminum gallium nitride layer.
25. A light emitting diode according to claim 23 wherein:
said opposite undoped gallium nitride layer is n-type; and
said doped layer of aluminum gallium nitride is p-type.
26. A light emitting diode according to claim 23 wherein said quantum well comprises multiple quantum wells.
27. A light emitting diode that is capable of emitting light in the electromagnetic spectrum, said light emitting diode comprising:
a substrate;
an InGaN quantum well;
a buffer layer between said substrate and said quantum well;
a first undoped gallium nitride layer on a first surface of said quantum well;
a second undoped gallium nitride layer directly on a second surface of said quantum well opposite said first surface; and
a doped layer of gallium nitride between said buffer and said first undoped gallium nitride layer;
an undoped layer of aluminum gallium nitride directly on said second undoped gallium nitride layer; and
a doped layer of aluminum gallium nitride on said undoped aluminum gallium nitride layer.
28. A light emitting diode according to claim 27 wherein said substrate is a conductive silicon carbide substrate and said buffer layer is a conductive buffer layer between said substrate and said quantum well, with said doped gallium nitride layer on said buffer layer.
29. A light emitting diode according to claim 27 further comprising:
an ohmic contact on one surface of said light emitting diode; and
another ohmic contact on the opposite surface of said light emitting diode and with said ohmic contacts in a vertical geometry orientation.
30. A light emitting diode that is capable of emitting light in the electromagnetic spectrum, said light emitting diode comprising:
a substrate;
an InGaN quantum well;
a buffer layer between said substrate and said quantum well;
a first undoped gallium nitride layer on a first surface of said quantum well;
a second undoped gallium nitride directly on a second surface of said quantum well opposite said first surface;
ohmic contacts in a vertical geometry orientation;
a doped layer of gallium nitride between said buffer and said first undoped gallium nitride layer;
an undoped layer of aluminum gallium nitride directly on said second undoped gallium nitride layer; and
a doped layer of aluminum gallium nitride on said undoped aluminum gallium nitride layer.
31. A light emitting diode according to claim 30 wherein said substrate is a conductive silicon carbide substrate and said buffer layer is a conductive buffer layer between said substrate and said quantum well, with said doped gallium nitride layer on said buffer layer.
US12/108,604 1998-09-16 2008-04-24 Vertical geometry InGaN LED Expired - Lifetime USRE42007E1 (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9985168B1 (en) 2014-11-18 2018-05-29 Cree, Inc. Group III nitride based LED structures including multiple quantum wells with barrier-well unit interface layers

Families Citing this family (119)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8101961B2 (en) * 2006-01-25 2012-01-24 Cree, Inc. Transparent ohmic contacts on light emitting diodes with growth substrates
US6825501B2 (en) 1997-08-29 2004-11-30 Cree, Inc. Robust Group III light emitting diode for high reliability in standard packaging applications
US6201262B1 (en) * 1997-10-07 2001-03-13 Cree, Inc. Group III nitride photonic devices on silicon carbide substrates with conductive buffer interlay structure
US6459100B1 (en) * 1998-09-16 2002-10-01 Cree, Inc. Vertical geometry ingan LED
DE10006738C2 (en) * 2000-02-15 2002-01-17 Osram Opto Semiconductors Gmbh Light-emitting component with improved light decoupling and method for its production
WO2001061765A1 (en) * 2000-02-15 2001-08-23 Osram Opto Semiconductors Gmbh Semiconductor component which emits radiation, and method for producing the same
GB2361354B (en) * 2000-04-13 2004-06-30 Arima Optoelectronics Corp White light emitting diode with single asymmetric quantum well in active layer
DE20111659U1 (en) * 2000-05-23 2001-12-13 Osram Opto Semiconductors Gmbh Component for optoelectronics
DE10056475B4 (en) 2000-11-15 2010-10-07 Osram Opto Semiconductors Gmbh GaN-based radiation-emitting semiconductor device with improved p-type conductivity and method for its production
US8507361B2 (en) 2000-11-27 2013-08-13 Soitec Fabrication of substrates with a useful layer of monocrystalline semiconductor material
US6800876B2 (en) 2001-01-16 2004-10-05 Cree, Inc. Group III nitride LED with undoped cladding layer (5000.137)
US6906352B2 (en) 2001-01-16 2005-06-14 Cree, Inc. Group III nitride LED with undoped cladding layer and multiple quantum well
US6740906B2 (en) * 2001-07-23 2004-05-25 Cree, Inc. Light emitting diodes including modifications for submount bonding
US7211833B2 (en) 2001-07-23 2007-05-01 Cree, Inc. Light emitting diodes including barrier layers/sublayers
US6791119B2 (en) * 2001-02-01 2004-09-14 Cree, Inc. Light emitting diodes including modifications for light extraction
KR100657786B1 (en) * 2001-04-24 2006-12-14 삼성전자주식회사 Face mask for using in clean room
US6649942B2 (en) * 2001-05-23 2003-11-18 Sanyo Electric Co., Ltd. Nitride-based semiconductor light-emitting device
US7692182B2 (en) * 2001-05-30 2010-04-06 Cree, Inc. Group III nitride based quantum well light emitting device structures with an indium containing capping structure
US6958497B2 (en) 2001-05-30 2005-10-25 Cree, Inc. Group III nitride based light emitting diode structures with a quantum well and superlattice, group III nitride based quantum well structures and group III nitride based superlattice structures
KR100422944B1 (en) * 2001-05-31 2004-03-12 삼성전기주식회사 Semiconductor LED device
CN101834245B (en) * 2001-06-15 2013-05-22 克里公司 GaN based LED formed on a SiC substrate
US20030090103A1 (en) * 2001-11-09 2003-05-15 Thomas Becker Direct mailing device
TW517403B (en) * 2002-01-10 2003-01-11 Epitech Technology Corp Nitride light emitting diode and manufacturing method for the same
CN102163664B (en) * 2002-02-08 2014-07-23 克里公司 Method of treating a silicon carbide substrate for improved epitaxial deposition and resulting structure and device
JP4150527B2 (en) * 2002-02-27 2008-09-17 日鉱金属株式会社 Crystal production method
JP4457564B2 (en) * 2002-04-26 2010-04-28 沖電気工業株式会社 Manufacturing method of semiconductor device
FR2840731B3 (en) * 2002-06-11 2004-07-30 Soitec Silicon On Insulator Method for manufacturing a substrate having a useful layer of single-crystal semiconductor material of improved properties
GB2416920B (en) * 2002-07-08 2006-09-27 Sumitomo Chemical Co Epitaxial substrate for compound semiconductor light - emitting device, method for producing the same and light - emitting device
SG115549A1 (en) * 2002-07-08 2005-10-28 Sumitomo Chemical Co Epitaxial substrate for compound semiconductor light emitting device, method for producing the same and light emitting device
KR100583163B1 (en) * 2002-08-19 2006-05-23 엘지이노텍 주식회사 Nitride semiconductor and fabrication method for thereof
KR100906921B1 (en) * 2002-12-09 2009-07-10 엘지이노텍 주식회사 Manufacturing method of light emitting diode
US6900067B2 (en) * 2002-12-11 2005-05-31 Lumileds Lighting U.S., Llc Growth of III-nitride films on mismatched substrates without conventional low temperature nucleation layers
AT353484T (en) * 2002-12-20 2007-02-15 Cree Inc Method for producing semiconductor devices with mesastructures and multiple passivation layers and related devices
US6917057B2 (en) * 2002-12-31 2005-07-12 Gelcore Llc Layered phosphor coatings for LED devices
US6987281B2 (en) 2003-02-13 2006-01-17 Cree, Inc. Group III nitride contact structures for light emitting devices
US6952024B2 (en) * 2003-02-13 2005-10-04 Cree, Inc. Group III nitride LED with silicon carbide cladding layer
US7170097B2 (en) * 2003-02-14 2007-01-30 Cree, Inc. Inverted light emitting diode on conductive substrate
US7123637B2 (en) * 2003-03-20 2006-10-17 Xerox Corporation Nitride-based laser diode with GaN waveguide/cladding layer
US7531380B2 (en) * 2003-04-30 2009-05-12 Cree, Inc. Methods of forming light-emitting devices having an active region with electrical contacts coupled to opposing surfaces thereof
US7087936B2 (en) * 2003-04-30 2006-08-08 Cree, Inc. Methods of forming light-emitting devices having an antireflective layer that has a graded index of refraction
US7714345B2 (en) 2003-04-30 2010-05-11 Cree, Inc. Light-emitting devices having coplanar electrical contacts adjacent to a substrate surface opposite an active region and methods of forming the same
US7592634B2 (en) * 2004-05-06 2009-09-22 Cree, Inc. LED fabrication via ion implant isolation
WO2004102686A1 (en) * 2003-05-09 2004-11-25 Cree, Inc. Led fabrication via ion implant isolation
WO2004109764A2 (en) * 2003-06-04 2004-12-16 Myung Cheol Yoo Method of fabricating vertical structure compound semiconductor devices
KR101034055B1 (en) 2003-07-18 2011-05-12 엘지이노텍 주식회사 Light emitting diode and method for manufacturing light emitting diode
US20050104072A1 (en) 2003-08-14 2005-05-19 Slater David B.Jr. Localized annealing of metal-silicon carbide ohmic contacts and devices so formed
US20050194584A1 (en) * 2003-11-12 2005-09-08 Slater David B.Jr. LED fabrication via ion implant isolation
JP2007511105A (en) * 2003-11-12 2007-04-26 クリー インコーポレイテッドCree Inc. Method for processing the back side of a semiconductor wafer having a light emitting device (LED) thereon, and an LED formed by the method
US7115908B2 (en) * 2004-01-30 2006-10-03 Philips Lumileds Lighting Company, Llc III-nitride light emitting device with reduced polarization fields
US7615689B2 (en) * 2004-02-12 2009-11-10 Seminis Vegatable Seeds, Inc. Methods for coupling resistance alleles in tomato
KR100664980B1 (en) * 2004-03-11 2007-01-09 삼성전기주식회사 Monolithic white light emitting device
KR100764457B1 (en) * 2004-03-18 2007-10-05 삼성전기주식회사 Monolithic white light emitting device
KR101254539B1 (en) * 2004-04-28 2013-04-19 버티클 인코퍼레이티드 Vertical structure semiconductor devices
TWI433343B (en) * 2004-06-22 2014-04-01 Verticle Inc Vertical structure semiconductor devices with improved light output
KR100616600B1 (en) * 2004-08-24 2006-08-28 삼성전기주식회사 Vertical nitride semiconductor light emitting diode
KR100649496B1 (en) * 2004-09-14 2006-11-24 삼성전기주식회사 Nitride semiconductor light emitting device and method of manufacturing the same
US7259402B2 (en) * 2004-09-22 2007-08-21 Cree, Inc. High efficiency group III nitride-silicon carbide light emitting diode
US8174037B2 (en) * 2004-09-22 2012-05-08 Cree, Inc. High efficiency group III nitride LED with lenticular surface
US7737459B2 (en) * 2004-09-22 2010-06-15 Cree, Inc. High output group III nitride light emitting diodes
US8513686B2 (en) * 2004-09-22 2013-08-20 Cree, Inc. High output small area group III nitride LEDs
US7432536B2 (en) 2004-11-04 2008-10-07 Cree, Inc. LED with self aligned bond pad
US7829909B2 (en) * 2005-11-15 2010-11-09 Verticle, Inc. Light emitting diodes and fabrication methods thereof
TWI389334B (en) * 2004-11-15 2013-03-11 Verticle Inc Method for fabricating and separating semicondcutor devices
KR100662191B1 (en) * 2004-12-23 2006-12-27 엘지이노텍 주식회사 Nitride semiconductor LED and fabrication method thereof
US8288942B2 (en) * 2004-12-28 2012-10-16 Cree, Inc. High efficacy white LED
US7378288B2 (en) * 2005-01-11 2008-05-27 Semileds Corporation Systems and methods for producing light emitting diode array
CN100401541C (en) * 2005-01-14 2008-07-09 财团法人工业技术研究院 Quantum spot/quantum well light emitting diode
US7951632B1 (en) * 2005-01-26 2011-05-31 University Of Central Florida Optical device and method of making
DE102005009060A1 (en) 2005-02-28 2006-09-07 Osram Opto Semiconductors Gmbh Module with radiation-emitting semiconductor bodies
US7446345B2 (en) * 2005-04-29 2008-11-04 Cree, Inc. Light emitting devices with active layers that extend into opened pits
US20060267043A1 (en) 2005-05-27 2006-11-30 Emerson David T Deep ultraviolet light emitting devices and methods of fabricating deep ultraviolet light emitting devices
KR100750932B1 (en) 2005-07-31 2007-08-22 삼성전자주식회사 Growth of Single Nitride-based Semiconductors Using Substrate Decomposition Prevention Layer And Manufacturing of High-quality Nitride-based Light Emitting Devices
JP4367393B2 (en) * 2005-09-30 2009-11-18 日立電線株式会社 Semiconductor light emitting device having a transparent conductive film
KR20080106402A (en) 2006-01-05 2008-12-05 일루미텍스, 인크. Separate optical device for directing light from an led
JP2007214378A (en) * 2006-02-09 2007-08-23 Rohm Co Ltd Nitride-based semiconductor element
JP2007220865A (en) * 2006-02-16 2007-08-30 Sumitomo Chemical Co Ltd Group iii nitride semiconductor light emitting device, and its manufacturing method
JP2007281257A (en) * 2006-04-07 2007-10-25 Toyoda Gosei Co Ltd Group iii nitride semiconductor light-emitting element
JP5274245B2 (en) 2006-04-10 2013-08-28 富士通株式会社 Compound semiconductor structure and manufacturing method thereof
US8008676B2 (en) 2006-05-26 2011-08-30 Cree, Inc. Solid state light emitting device and method of making same
WO2007142946A2 (en) 2006-05-31 2007-12-13 Cree Led Lighting Solutions, Inc. Lighting device and method of lighting
US7646024B2 (en) * 2006-08-18 2010-01-12 Cree, Inc. Structure and method for reducing forward voltage across a silicon carbide-group III nitride interface
CN101553928B (en) 2006-10-02 2011-06-01 伊鲁米特克有限公司 Led system and method
CN101601135B (en) 2007-01-22 2012-06-27 科锐公司 Illumination devices using externally interconnected arrays of light emitting devices, and methods of fabricating same
WO2008091837A2 (en) * 2007-01-22 2008-07-31 Cree Led Lighting Solutions, Inc. Fault tolerant light emitters, systems incorporating fault tolerant light emitters and methods of fabricating fault tolerant light emitters
KR100818466B1 (en) * 2007-02-13 2008-04-02 삼성전기주식회사 Light emitting devices
KR100849826B1 (en) * 2007-03-29 2008-07-31 삼성전기주식회사 Light emitting device and package including the same
US9484499B2 (en) * 2007-04-20 2016-11-01 Cree, Inc. Transparent ohmic contacts on light emitting diodes with carrier substrates
US20080283864A1 (en) * 2007-05-16 2008-11-20 Letoquin Ronan P Single Crystal Phosphor Light Conversion Structures for Light Emitting Devices
US7851343B2 (en) * 2007-06-14 2010-12-14 Cree, Inc. Methods of forming ohmic layers through ablation capping layers
KR100891761B1 (en) 2007-10-19 2009-04-07 삼성전기주식회사 Semiconductor light emitting device, manufacturing method thereof and semiconductor light emitting device package using the same
US7482674B1 (en) * 2007-12-17 2009-01-27 The United States Of America As Represented By The Secretary Of The Navy Crystalline III-V nitride films on refractory metal substrates
CN101939849A (en) 2008-02-08 2011-01-05 伊鲁米特克有限公司 Be used for the system and method that emitter layer is shaped
JP5085369B2 (en) * 2008-02-18 2012-11-28 日本オクラロ株式会社 Nitride semiconductor light emitting device and manufacturing method thereof
CN101728451B (en) * 2008-10-21 2013-10-30 展晶科技(深圳)有限公司 Semiconductor photoelectric element
TW201034256A (en) 2008-12-11 2010-09-16 Illumitex Inc Systems and methods for packaging light-emitting diode devices
US8013414B2 (en) * 2009-02-18 2011-09-06 Alpha & Omega Semiconductor, Inc. Gallium nitride semiconductor device with improved forward conduction
US20110012141A1 (en) 2009-07-15 2011-01-20 Le Toquin Ronan P Single-color wavelength-converted light emitting devices
WO2011019920A1 (en) 2009-08-12 2011-02-17 Georgia State University Research Foundation, Inc. High pressure chemical vapor deposition apparatuses, methods, and compositions produced therewith
US8449128B2 (en) 2009-08-20 2013-05-28 Illumitex, Inc. System and method for a lens and phosphor layer
US8585253B2 (en) 2009-08-20 2013-11-19 Illumitex, Inc. System and method for color mixing lens array
WO2011084478A1 (en) * 2009-12-15 2011-07-14 Lehigh University Nitride based devices including a symmetrical quantum well active layer having a central low bandgap delta-layer
US8604461B2 (en) 2009-12-16 2013-12-10 Cree, Inc. Semiconductor device structures with modulated doping and related methods
US8536615B1 (en) 2009-12-16 2013-09-17 Cree, Inc. Semiconductor device structures with modulated and delta doping and related methods
JP5392104B2 (en) * 2010-01-15 2014-01-22 住友電気工業株式会社 Light emitting device
US8575592B2 (en) * 2010-02-03 2013-11-05 Cree, Inc. Group III nitride based light emitting diode structures with multiple quantum well structures having varying well thicknesses
US9991427B2 (en) * 2010-03-08 2018-06-05 Cree, Inc. Photonic crystal phosphor light conversion structures for light emitting devices
CN101908591A (en) * 2010-06-23 2010-12-08 山东华光光电子有限公司 Preparation method for ohmic contact electrode for LED with SiC substrate
US20120153297A1 (en) * 2010-07-30 2012-06-21 The Regents Of The University Of California Ohmic cathode electrode on the backside of nonpolar m-plane (1-100) and semipolar (20-21) bulk gallium nitride substrates
CN108198749A (en) 2010-11-04 2018-06-22 皇家飞利浦电子股份有限公司 Sony ericsson mobile comm ab based on crystallization relaxation structure
CN102064251B (en) * 2010-11-23 2012-12-05 吉林大学 High-power SiC substrate vertical structure light-emitting diode and preparation method thereof
TWI458129B (en) 2010-12-21 2014-10-21 Lextar Electronics Corp Light emitting diode chip structure and fabrication method thereof
TWI495154B (en) 2012-12-06 2015-08-01 Genesis Photonics Inc Semiconductor structure
WO2015084258A1 (en) 2013-12-02 2015-06-11 Nanyang Technological University Light-emitting device and method of forming the same
JP6198004B2 (en) * 2014-02-19 2017-09-20 豊田合成株式会社 Group III nitride semiconductor light emitting device and method of manufacturing the same
TW201601343A (en) * 2014-06-30 2016-01-01 新世紀光電股份有限公司 Semiconductor structure
CN105449063B (en) * 2016-01-22 2017-11-14 西安中为光电科技有限公司 Improve the structure and its method of the ultraviolet optical purity of ultraviolet LED
TW201813091A (en) 2016-09-19 2018-04-01 新世紀光電股份有限公司 Semiconductor device containing nitrogen
US20190164944A1 (en) * 2017-11-27 2019-05-30 Seoul Viosys Co., Ltd. Led unit for display and display apparatus having the same
CN108321265A (en) * 2018-01-31 2018-07-24 映瑞光电科技(上海)有限公司 A kind of LED epitaxial structure and preparation method thereof

Citations (40)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4313125A (en) * 1979-06-21 1982-01-26 Bell Telephone Laboratories, Incorporated Light emitting semiconductor devices
US4862471A (en) * 1988-04-22 1989-08-29 University Of Colorado Foundation, Inc. Semiconductor light emitting device
US5004135A (en) * 1988-07-11 1991-04-02 Societe Anonyme Dite: Millet Adjustable frame for backpack
US5146465A (en) * 1991-02-01 1992-09-08 Apa Optics, Inc. Aluminum gallium nitride laser
EP0541373A2 (en) * 1991-11-08 1993-05-12 Nichia Chemical Industries, Ltd. Method of manufacturing p-type compound semiconductor
US5290393A (en) * 1991-01-31 1994-03-01 Nichia Kagaku Kogyo K.K. Crystal growth method for gallium nitride-based compound semiconductor
EP0599224A1 (en) * 1992-11-20 1994-06-01 Nichia Chemical Industries, Ltd. Light-emitting gallium nitride-based compound semiconductor device
US5334277A (en) * 1990-10-25 1994-08-02 Nichia Kagaky Kogyo K.K. Method of vapor-growing semiconductor crystal and apparatus for vapor-growing the same
EP0622858A2 (en) * 1993-04-28 1994-11-02 Nichia Chemical Industries, Ltd. Gallium nitride-based III-V group compound semiconductor device and method of producing the same
US5432808A (en) * 1993-03-15 1995-07-11 Kabushiki Kaisha Toshiba Compound semicondutor light-emitting device
US5433169A (en) * 1990-10-25 1995-07-18 Nichia Chemical Industries, Ltd. Method of depositing a gallium nitride-based III-V group compound semiconductor crystal layer
EP0497350B1 (en) * 1991-01-31 1995-08-02 Nichia Kagaku Kogyo K.K. Crystal growth method for gallium nitride-based compound semiconductor
WO1996009653A1 (en) * 1994-09-20 1996-03-28 Cree Research Inc. Vertical geometry light emitting diode with group iii nitride active layer and extended lifetime
EP0716457A2 (en) * 1994-12-02 1996-06-12 Nichia Chemical Industries, Ltd. Nitride semiconductor light-emitting device
EP0732754A2 (en) * 1995-03-17 1996-09-18 Toyoda Gosei Co., Ltd. Light-emitting semiconductor device using group III nitride compound
US5585648A (en) * 1995-02-03 1996-12-17 Tischler; Michael A. High brightness electroluminescent device, emitting in the green to ultraviolet spectrum, and method of making the same
EP0772249A2 (en) * 1995-11-06 1997-05-07 Nichia Chemical Industries, Ltd. Nitride semiconductor device
US5661074A (en) * 1995-02-03 1997-08-26 Advanced Technology Materials, Inc. High brightness electroluminescent device emitting in the green to ultraviolet spectrum and method of making the same
US5679965A (en) * 1995-03-29 1997-10-21 North Carolina State University Integrated heterostructures of Group III-V nitride semiconductor materials including epitaxial ohmic contact, non-nitride buffer layer and methods of fabricating same
US5684309A (en) * 1996-07-11 1997-11-04 North Carolina State University Stacked quantum well aluminum indium gallium nitride light emitting diodes
JPH1093192A (en) * 1996-07-26 1998-04-10 Toshiba Corp Gallium nitride compound semiconductor laser and manufacture thereof
JPH10145500A (en) * 1996-11-15 1998-05-29 Oki Electric Ind Co Ltd Private telephone system
US5786606A (en) * 1995-12-15 1998-07-28 Kabushiki Kaisha Toshiba Semiconductor light-emitting device
JPH10261816A (en) * 1997-03-19 1998-09-29 Fujitsu Ltd Semiconductor light emitting element and its manufacture
US5874747A (en) * 1996-02-05 1999-02-23 Advanced Technology Materials, Inc. High brightness electroluminescent device emitting in the green to ultraviolet spectrum and method of making the same
US5898185A (en) * 1997-01-24 1999-04-27 International Business Machines Corporation Hybrid organic-inorganic semiconductor light emitting diodes
US5900647A (en) * 1996-02-05 1999-05-04 Sharp Kabushiki Kaisha Semiconductor device with SiC and GaAlInN
US5923940A (en) * 1997-07-24 1999-07-13 Xerox Corporation Cleaning brush having fibers of different lengths
US5932896A (en) * 1996-09-06 1999-08-03 Kabushiki Kaisha Toshiba Nitride system semiconductor device with oxygen
US5990496A (en) * 1996-04-26 1999-11-23 Sanyo Electric Co., Ltd. Light emitting device with cap layer
US6015979A (en) * 1997-08-29 2000-01-18 Kabushiki Kaisha Toshiba Nitride-based semiconductor element and method for manufacturing the same
US6017774A (en) * 1995-12-24 2000-01-25 Sharp Kabushiki Kaisha Method for producing group III-V compound semiconductor and fabricating light emitting device using such semiconductor
US6040588A (en) * 1996-09-08 2000-03-21 Toyoda Gosei Co., Ltd. Semiconductor light-emitting device
US6043513A (en) * 1995-01-18 2000-03-28 Telefonaktiebolaget Lm Ericsson Method of producing an ohmic contact and a semiconductor device provided with such ohmic contact
US6046464A (en) * 1995-03-29 2000-04-04 North Carolina State University Integrated heterostructures of group III-V nitride semiconductor materials including epitaxial ohmic contact comprising multiple quantum well
US6057565A (en) * 1996-09-26 2000-05-02 Kabushiki Kaisha Toshiba Semiconductor light emitting device including a non-stoichiometric compound layer and manufacturing method thereof
US6172382B1 (en) * 1997-01-09 2001-01-09 Nichia Chemical Industries, Ltd. Nitride semiconductor light-emitting and light-receiving devices
US6201262B1 (en) * 1997-10-07 2001-03-13 Cree, Inc. Group III nitride photonic devices on silicon carbide substrates with conductive buffer interlay structure
US6382800B2 (en) * 1997-03-21 2002-05-07 Ricoh Company, Ltd. Light emitting semiconductor devices
US6459100B1 (en) * 1998-09-16 2002-10-01 Cree, Inc. Vertical geometry ingan LED

Family Cites Families (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5043513A (en) * 1990-03-07 1991-08-27 Mobil Oil Corp. Catalytic hydrodealkylation of aromatics
US5319657A (en) 1991-10-08 1994-06-07 Matsushita Electric Industrial Co., Ltd. Semiconductor laser of modulation doping quantum well structure with stopper against dopant dispersion and manufacturing method thereof
JP2576819Y2 (en) * 1992-07-13 1998-07-16 オイレス工業株式会社 Bearing device for steering column
US5604135A (en) * 1994-08-12 1997-02-18 Cree Research, Inc. Method of forming green light emitting diode in silicon carbide
JP3728332B2 (en) 1995-04-24 2005-12-21 シャープ株式会社 Compound semiconductor light emitting device
JPH08316581A (en) * 1995-05-18 1996-11-29 Sanyo Electric Co Ltd Semiconductor device and semiconductor light emitting element
JP2830814B2 (en) * 1996-01-19 1998-12-02 日本電気株式会社 Crystal growth method of gallium nitride based compound semiconductor and method of manufacturing semiconductor laser
US5923690A (en) * 1996-01-25 1999-07-13 Matsushita Electric Industrial Co., Ltd. Semiconductor laser device
JP3754120B2 (en) * 1996-02-27 2006-03-08 株式会社東芝 Semiconductor light emitting device
US5987048A (en) * 1996-07-26 1999-11-16 Kabushiki Kaisha Toshiba Gallium nitride-based compound semiconductor laser and method of manufacturing the same
JPH10145006A (en) 1996-09-10 1998-05-29 Toshiba Corp Compound semiconductor device
JP3767031B2 (en) * 1996-09-10 2006-04-19 松下電器産業株式会社 Semiconductor light emitting device and manufacturing method thereof
JP3419280B2 (en) * 1996-11-05 2003-06-23 日亜化学工業株式会社 Light emitting device
JP3316838B2 (en) * 1997-01-31 2002-08-19 日亜化学工業株式会社 Light emitting device
US5923946A (en) * 1997-04-17 1999-07-13 Cree Research, Inc. Recovery of surface-ready silicon carbide substrates
JP3216596B2 (en) * 1998-01-08 2001-10-09 日亜化学工業株式会社 Gallium nitride based compound semiconductor light emitting device

Patent Citations (46)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4313125A (en) * 1979-06-21 1982-01-26 Bell Telephone Laboratories, Incorporated Light emitting semiconductor devices
US4862471A (en) * 1988-04-22 1989-08-29 University Of Colorado Foundation, Inc. Semiconductor light emitting device
US5004135A (en) * 1988-07-11 1991-04-02 Societe Anonyme Dite: Millet Adjustable frame for backpack
US5334277A (en) * 1990-10-25 1994-08-02 Nichia Kagaky Kogyo K.K. Method of vapor-growing semiconductor crystal and apparatus for vapor-growing the same
US5433169A (en) * 1990-10-25 1995-07-18 Nichia Chemical Industries, Ltd. Method of depositing a gallium nitride-based III-V group compound semiconductor crystal layer
EP0497350B1 (en) * 1991-01-31 1995-08-02 Nichia Kagaku Kogyo K.K. Crystal growth method for gallium nitride-based compound semiconductor
US5290393A (en) * 1991-01-31 1994-03-01 Nichia Kagaku Kogyo K.K. Crystal growth method for gallium nitride-based compound semiconductor
US5146465A (en) * 1991-02-01 1992-09-08 Apa Optics, Inc. Aluminum gallium nitride laser
US5321713A (en) * 1991-02-01 1994-06-14 Khan Muhammad A Aluminum gallium nitride laser
US5306662A (en) * 1991-11-08 1994-04-26 Nichia Chemical Industries, Ltd. Method of manufacturing P-type compound semiconductor
EP0541373A2 (en) * 1991-11-08 1993-05-12 Nichia Chemical Industries, Ltd. Method of manufacturing p-type compound semiconductor
US5578839A (en) * 1992-11-20 1996-11-26 Nichia Chemical Industries, Ltd. Light-emitting gallium nitride-based compound semiconductor device
EP0599224A1 (en) * 1992-11-20 1994-06-01 Nichia Chemical Industries, Ltd. Light-emitting gallium nitride-based compound semiconductor device
US5432808A (en) * 1993-03-15 1995-07-11 Kabushiki Kaisha Toshiba Compound semicondutor light-emitting device
EP0622858A2 (en) * 1993-04-28 1994-11-02 Nichia Chemical Industries, Ltd. Gallium nitride-based III-V group compound semiconductor device and method of producing the same
US5652434A (en) * 1993-04-28 1997-07-29 Nichia Chemical Industries, Ltd. Gallium nitride-based III-V group compound semiconductor
US5563422A (en) * 1993-04-28 1996-10-08 Nichia Chemical Industries, Ltd. Gallium nitride-based III-V group compound semiconductor device and method of producing the same
WO1996009653A1 (en) * 1994-09-20 1996-03-28 Cree Research Inc. Vertical geometry light emitting diode with group iii nitride active layer and extended lifetime
EP0716457A2 (en) * 1994-12-02 1996-06-12 Nichia Chemical Industries, Ltd. Nitride semiconductor light-emitting device
US6043513A (en) * 1995-01-18 2000-03-28 Telefonaktiebolaget Lm Ericsson Method of producing an ohmic contact and a semiconductor device provided with such ohmic contact
US5585648A (en) * 1995-02-03 1996-12-17 Tischler; Michael A. High brightness electroluminescent device, emitting in the green to ultraviolet spectrum, and method of making the same
US5661074A (en) * 1995-02-03 1997-08-26 Advanced Technology Materials, Inc. High brightness electroluminescent device emitting in the green to ultraviolet spectrum and method of making the same
EP0732754A2 (en) * 1995-03-17 1996-09-18 Toyoda Gosei Co., Ltd. Light-emitting semiconductor device using group III nitride compound
US6046464A (en) * 1995-03-29 2000-04-04 North Carolina State University Integrated heterostructures of group III-V nitride semiconductor materials including epitaxial ohmic contact comprising multiple quantum well
US5679965A (en) * 1995-03-29 1997-10-21 North Carolina State University Integrated heterostructures of Group III-V nitride semiconductor materials including epitaxial ohmic contact, non-nitride buffer layer and methods of fabricating same
EP0772249A2 (en) * 1995-11-06 1997-05-07 Nichia Chemical Industries, Ltd. Nitride semiconductor device
US5786606A (en) * 1995-12-15 1998-07-28 Kabushiki Kaisha Toshiba Semiconductor light-emitting device
US6017774A (en) * 1995-12-24 2000-01-25 Sharp Kabushiki Kaisha Method for producing group III-V compound semiconductor and fabricating light emitting device using such semiconductor
US5900647A (en) * 1996-02-05 1999-05-04 Sharp Kabushiki Kaisha Semiconductor device with SiC and GaAlInN
US5874747A (en) * 1996-02-05 1999-02-23 Advanced Technology Materials, Inc. High brightness electroluminescent device emitting in the green to ultraviolet spectrum and method of making the same
US5990496A (en) * 1996-04-26 1999-11-23 Sanyo Electric Co., Ltd. Light emitting device with cap layer
US5684309A (en) * 1996-07-11 1997-11-04 North Carolina State University Stacked quantum well aluminum indium gallium nitride light emitting diodes
JPH1093192A (en) * 1996-07-26 1998-04-10 Toshiba Corp Gallium nitride compound semiconductor laser and manufacture thereof
US5932896A (en) * 1996-09-06 1999-08-03 Kabushiki Kaisha Toshiba Nitride system semiconductor device with oxygen
US6040588A (en) * 1996-09-08 2000-03-21 Toyoda Gosei Co., Ltd. Semiconductor light-emitting device
US6057565A (en) * 1996-09-26 2000-05-02 Kabushiki Kaisha Toshiba Semiconductor light emitting device including a non-stoichiometric compound layer and manufacturing method thereof
JPH10145500A (en) * 1996-11-15 1998-05-29 Oki Electric Ind Co Ltd Private telephone system
US6172382B1 (en) * 1997-01-09 2001-01-09 Nichia Chemical Industries, Ltd. Nitride semiconductor light-emitting and light-receiving devices
US5898185A (en) * 1997-01-24 1999-04-27 International Business Machines Corporation Hybrid organic-inorganic semiconductor light emitting diodes
JPH10261816A (en) * 1997-03-19 1998-09-29 Fujitsu Ltd Semiconductor light emitting element and its manufacture
US6382800B2 (en) * 1997-03-21 2002-05-07 Ricoh Company, Ltd. Light emitting semiconductor devices
US5923940A (en) * 1997-07-24 1999-07-13 Xerox Corporation Cleaning brush having fibers of different lengths
US6015979A (en) * 1997-08-29 2000-01-18 Kabushiki Kaisha Toshiba Nitride-based semiconductor element and method for manufacturing the same
US6201262B1 (en) * 1997-10-07 2001-03-13 Cree, Inc. Group III nitride photonic devices on silicon carbide substrates with conductive buffer interlay structure
US6459100B1 (en) * 1998-09-16 2002-10-01 Cree, Inc. Vertical geometry ingan LED
US7034328B2 (en) * 1998-09-16 2006-04-25 Cree, Inc. Vertical geometry InGaN LED

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
Amano et al. "Gallium nitride and related materials," Material Research Society Symposium Proceedings, vol. 395, pp. 869-877. *
Doverspike, K., Status of Nitride Based Light Emitting and Laser Diodes on SiC; Nitride Semiconductors Symposium, Nitride Semiconductors Symposium, Boston, MA, USA, Dec. 1-5, 1997, pp. 1169-1178. *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9985168B1 (en) 2014-11-18 2018-05-29 Cree, Inc. Group III nitride based LED structures including multiple quantum wells with barrier-well unit interface layers
US10224454B2 (en) 2014-11-18 2019-03-05 Cree, Inc. Group III nitride based LED structures including multiple quantum wells with barrier-well unit interface layers

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