WO2013131824A1

WO2013131824A1 - Optoelectronic component

Info

Publication number: WO2013131824A1
Application number: PCT/EP2013/054176
Authority: WO
Inventors: Alexander Baumgartner; Kirstin Petersen
Original assignee: Osram Opto Semiconductors Gmbh
Priority date: 2012-03-07
Filing date: 2013-03-01
Publication date: 2013-09-12
Also published as: DE102012101920A1

Abstract

Disclosed is an optoelectronic component comprising a layer sequence (1) having an active region that emits primary electromagnetic radiation; a conversion material that is arranged in the ray path of the primary electromagnetic radiation and at least partially converts the primary electromagnetic radiation into a secondary electromagnetic radiation. The conversion material comprises a first luminescent substance (6-1) having the general composition A₃B₅O₁₂ and a second luminescent substance (6-2) having the general composition M₂Si₅N₈, A comprising one of the elements Y, Lu, Gd and/or Ce or combinations from Y, Lu, Gd and/or Ce, B being A1, in the second luminescent substance (6-2) Ca being contained as a part of component M at a proportion of 2.5 mol-% to 25 mol-%, component M of the second luminescent substance (6-2) containing Ba at a proportion of greater than or equal to 40 mol-%, component M of the second luminescent substance (6-2) containing Eu at a proportion of 0.5 mol-% to 10 mol-%, and component M of the second luminescent substance (6-2) containing Sr.

Description

description

Optoelectronic component

The present invention relates to an optoelectronic component.

Radiation emitting components, such as

Light-emitting diodes (LEDs) often contain converter materials in order to convert the radiation emitted by a radiation source into radiation with a changed, longer wavelength. The efficiency of the converter material is generally dependent on its position of the absorption maximum with respect to the wavelength range of the electromagnetic

Primary radiation, temperature and / or relative

Humidity. Increased brightness losses and

Aging phenomena of the device may be the result of high temperatures and / or high humidity during operation of the device, which can lead to failure of the optoelectronic device in the worst case.

An object to be solved is to specify an optoelectronic component which has improved stability

having .

This object is solved by the subject matters with the features of the independent claims. advantageous

Embodiments and developments of the objects are characterized in the dependent claims and will become apparent from the following description and the drawings. An optoelectronic component according to one embodiment comprises a layer sequence with an active region which emits electromagnetic primary radiation

Conversion material in the beam path of the

is arranged electromagnetic primary radiation and at least partially converts the electromagnetic primary radiation into an electromagnetic secondary radiation. The conversion material comprises a first phosphor having the general composition A ₃ B ₅ O ₁ 2 and a second

A phosphor having the general composition M ₂ S1 ₅ N ₈ , wherein A comprises one of the elements Y, Lu, Gd and / or Ce or combinations of Y, Lu, Gd and / or Ce, wherein B is AI, and wherein M is a combination from Ca, Sr, Ba and Eu. In this case, the first phosphor and / or the second phosphor need not necessarily have mathematically exact compositions according to the above formulas. Rather, they may, for example, have one or more additional dopants, as well as additional constituents. For the sake of simplicity, however, the above formulas contain only the essential components.

It should be noted at this point that the term "component" here not only finished components, such as light-emitting diodes (LEDs) or laser diodes are to be understood, but also substrates and / or

Semiconductor layers, so for example already a

Composite of a copper layer and a semiconductor layer constitute a component and a component of a

can form the parent second component in which, for example, additional electrical connections are available. The optoelectronic component according to the invention can be, for example, a thin-film semiconductor chip, in particular a thin-film LED chip. In this context, "layer sequence" is understood as meaning a layer sequence comprising more than one layer, for example a sequence of a p-doped and an n-doped semiconductor layer, wherein the layers are arranged one above the other.

Likewise, for the component A of a first phosphor, one or at least two elements selected from the group comprising Y, Lu, Gd and Ce can be used, the sum of which amounts to 100%.

The proportions of Ca, Sr, Ba and Eu as component M in the second phosphor give a total of 100%. In other words, the component M in the second phosphor is composed of both Ca and Sr, and Ba and Eu, and the sum of the proportions of Ca and Sr and Ba and Eu is 100%. It follows that no proportion of Ca or Sr or Ba or Eu as component M is 0. Here and in the following, color specifications with respect to emitting phosphors denote the respective spectral range of the electromagnetic radiation.

Here and below, electromagnetic radiation, in particular electromagnetic radiation having one or more wavelengths or wavelength ranges from an ultraviolet to infrared spectral range, also referred to as light. In particular, light may be visible light and wavelengths or wavelength ranges from a visible spectral range between about 350 nm and about 800 nm

include. Visible light can be here and below

for example, by its color locus with cx and cy chromaticity coordinates according to the so-known to a person skilled in the art be characterized CIE-1931 color chart or CIE standard color chart.

As white light or light with a white light or color impression here and in the following can light with a

Color locus, which corresponds to the color locus of a planck blackbody radiator or by less than 0.07 and preferably by less than 0.05, for example 0.03, in cx and / or cy color coordinates from the color locus of a

deviates from Planck's black body radiator. Furthermore, here and below a white light impression

designated luminous impression are caused by light, which has a color rendering index (CRI) of greater than or equal to 60, preferably greater than or equal to 80, known to a person skilled in the art.

The inventors have surprisingly found that in the operation of an optoelectronic device a

Combining the wavelength or the wavelength range of the electromagnetic primary radiation with the first

Phosphor and the second phosphor increased stability of the optoelectronic device at high

Temperatures, a high relative humidity and / or high water vapor pressure arises. Continues to emerge

In addition to the long-term stability in humidity a very good conversion efficiency of the electromagnetic

Primary radiation into a secondary electromagnetic radiation, a higher brightness, a high color rendering index (CRI, R9, Ra8) and a better color impression of the light emitted by the device compared to conventional

optoelectronic components. Furthermore, the shows

Combination of first and second phosphor in the operation of an optoelectronic component a high Long-term stability and / or high stability to high temperatures.

According to one embodiment, the layer sequence may be a semiconductor layer sequence, wherein the in the

Semiconductor layer sequence occurring semiconductor materials are not limited, provided that at least partially

Have electroluminescence. It will be, for example

Use is made of compounds selected from indium, gallium, aluminum, nitrogen, phosphorus, arsenic, oxygen, silicon, carbon, and combinations thereof. But there may be other elements and additions

be used. The layer sequence with an active

Range may be based on, for example, nitride compound semiconductor materials. "Based on nitride compound semiconductor material" in the present context means that the semiconductor layer sequence or at least a part thereof, a nitride compound semiconductor material, preferably comprises or consists of Al _n Ga _m In _n _m , where 0 -S n <1 , 0 -S m <1 and n + m <1. In this case, this material does not necessarily have to have a mathematically exact composition according to the above formula, but rather it can be, for example, one or more dopants and additional constituents

exhibit. For the sake of simplicity, however, the above formula contains only the essential constituents of the crystal lattice (Al, Ga, In, N), even if these can be partially replaced and / or supplemented by small amounts of further substances.

The semiconductor layer sequence can be used as active region

for example, a conventional pn junction, a

Double heterostructure, a single quantum well structure (SQW structure) or a multiple quantum well structure (MQW structure) have. The semiconductor layer sequence can be next to the active region comprises further functional layers and functional regions, such as p- or n-doped ones

Charge carrier transport layers, ie electron or

Hole transport layers, p- or n-doped confinement or cladding layers, buffer layers and / or electrodes and combinations thereof. Such structures include the active region or the further functional layers and

Areas relating to those skilled in particular

in terms of structure, function and structure known and are therefore not explained in detail here.

Alternatively, it is possible to an organic light emitting diode (OLED) as an opto-electronic device to select, with play, the light emitted from the OLED electromagnetic primary radiation is converted by an in-beam path of the electromagnetic primary radiation conversion material in an electromagnetic secondary radiation at ^¬.

The second phosphor, for example of the type M2Si5Ng ^ shows a much higher stability at high temperatures, such as 85 ° C to 120 ° C, and / or at varying ambient temperatures and currents or currents. This higher stability and in addition an optimized position of the emission of the second phosphor, for example of the type M2Si5 g ^ shows a much more stable color rendering index

(color rendering index, CRI and color rendering index with 8 reference colors, Ra8), a higher saturation red color rendering index (R9) that stays above 0 under all conditions at CRI 80. Furthermore, the second phosphor, for example of the type M2Si5Ng, without further

Stabilization measures in an optoelectronic

Component to be used and is humid and

temperature stable. Furthermore, the color locus of the second phosphor of the type M2Si5 g can be adjusted by varying the ratio of the cations of the component M, Ca ²⁺ , Sr ²⁺ , Ba ²⁺ and Eu ²⁺

Eye sensitivity of an external observer and

at the same time on the emission of electromagnetic

Primary radiation and the electromagnetic secondary radiation of the first phosphor (hereinafter first

electromagnetic secondary radiation) that a temperature and current stable behavior of the total emission, so the perceived by an external observer

electromagnetic radiation of the device is achieved. At the same time, a sufficiently high color rendering index is achieved. Furthermore, a significant stabilization of the color locus of the device is observable. In addition, through

Using the second phosphor, the long-term stability in humidity of the optoelectronic device clearly

be increased.

The electromagnetic secondary radiation of the second

Fluorescent type M2Si5Ng (hereinafter second

secondary electromagnetic radiation) can be shifted toward longer wavelengths by reducing the average ionic size of the cations Ca ²⁺ , Sr ²⁺ , Ba ²⁺ or by increasing the Eu content in the second phosphor.

Here and below, 1 mole percent (mole%) equals 1 atomic percent (at%).

According to one embodiment, in the second phosphor, Ca is contained as part of the component M to a proportion of 2.5 mol% to 25 mol%. Furthermore, the second phosphor may contain Ba in a proportion of greater than or equal to 40 mol%, for example 40 mol% to 70 mol%, preferably greater than or equal to 50 mol%. According to at least one embodiment of the invention, the second phosphor Eu contains in a proportion of 0.5 mol% to 10 mol%, preferably 2 mol% to 6 mol%, particularly preferably 4 mol%. In this case, Eu can serve for activation and / or doping of the second phosphor.

According to one embodiment, in the second phosphor Sr as part of the component M to a proportion of 20 mol% to 50 mol%, in particular 30 mol% to 40 mol%, for example 36 mol% included.

In accordance with at least one embodiment of the invention, the second phosphor has the composition

(Sr _{Q ^} 3gBa _{Q ^} 5Ca _{Q ^]} _EU _Q ^ _Q 4) 2Si5 g. By combining Sr,

Ba, Ca and Eu are in the second phosphor with the

Composition (Sr _{Q ^} 3gBa _{Q ^} 5Ca _{Q ^} IEU _Q ^ 04) 2 ^ ί5 ^Ν 8 a high thermal stability and stability over

Moisture, long-term stability of the device, stability of the color location and stability of the

Color rendering index (Ra8, CRI, R9) achieved.

According to a further embodiment, the first and second phosphors may be formed as particles.

The component A of the first phosphor having the general composition A ₃ B ₅ O ₁ 2 may be an activator and / or

Dopant include. One on the wavelength of

electromagnetic radiation optimally adapted Composition of the first phosphor can be achieved by varying the ratios (Y, Lu, Gd, Ce) to Al.

According to a further embodiment, the first comprises

Phosphor Ce as component A in a proportion of 0.5 mol% to 5 mol%, preferably from 2.5 mol% to 5 mol%,

for example, 3.5 mol%. Ce may serve as activator and / or dopant in the first phosphor. Due to the high concentration of Ce as activator in the first phosphor and a good match of the absorption maximum of the first phosphor with the primary electromagnetic radiation results in a higher conversion efficiency of the first

Phosphor compared to conventional phosphors, such as yellow or green emitting phosphors.

Furthermore, the first phosphor is long-term stable and improves temperature stability.

According to a further embodiment, the component A of the first phosphor may comprise Y. Here, Y may be present in a proportion in the first phosphor of from 95 mol% to 99.5 mol%, for example, 99 mol%.

According to a further embodiment, in the component A, Lu may be present at a level of from 95 mol% to 99.5 mol%, for example 99 mol%.

According to a further embodiment, the first

Phosphor composition (yi_ _y Ce _y) ₃ Al ₅ O ₁ 2 0 005 ^ y ^ 0.05, for example, y = 0, 035 or (Lui_ _x Ce _x) ₃ Al ₅ O ₁ 2 0.005 <x < 0.05, for example, y = 0, or 035 (LUI _a -by _a Ce _b) 3AI 5O ₁ 2 0 <a <1, for example a = 0.99 and 0.005 <b ^ 0.05, for example, b = 0.035. According to one embodiment, the primary electromagnetic radiation has a wavelength in the range 445 nm to 565 nm. According to a further embodiment, the

electromagnetic primary radiation a wavelength in the

Range 450 nm to 470 nm.

According to a further embodiment, the

electromagnetic primary radiation a wavelength in the

Range 515 nm to 560 nm.

The choice of the wavelength or the wavelength range of the electromagnetic primary radiation in the range of greater than 445 nm leads to an improved intrinsic

Temperature stability of the optoelectronic component.

By selecting the wavelength or the wavelength range of the electromagnetic primary radiation and the

Conversion material is the color point of the total emission of the optoelectronic device even when changing the

Temperature and / or the forward current I _f little influenced and thus achieves a temperature and current stabilized behavior of the total emission. The color stability of the

Total emission is enhanced by the optimized interaction of the primary electromagnetic radiation with the sensitivity of the blue receptor in the human eye (CIE-Z,

Blue sensitivity of the eye according to CIE standard) significantly improved. Furthermore, by the improved

Temperature stability significantly increases the efficiency of the device at higher temperatures.

The first phosphor having the composition (yi_ _y Ce _y) ₃ Al ₅ O ₁ 2 0, 005 <y <0.05, for example, y = 0, or 035 (LUI _a - _b Y _a Ce _b ) 3AI5O ₁ 2 with 0 <a <1, for example a = 0.99 and 0.005 b ^ 0.05, for example b = 0.035, due to its location of the absorption maximum between 450 and 470 nm optimally and efficiently from the electromagnetic primary radiation, which is for example in the range of 450 nm to 470 nm, are excited. In this case, the first phosphor has a

Long-term stability to moisture and improved temperature stability. According to a further embodiment, in the operation of the optoelectronic component, the electromagnetic

Primary radiation emitted from the layer sequence with an active region and strikes in a conversion region on the conversion material, which in the beam path of the

is arranged electromagnetic primary radiation and is suitable, the electromagnetic primary radiation

at least partially absorb and as electromagnetic secondary radiation with an at least partially different from the electromagnetic primary radiation

Wavelength range to emit.

An area designed as a layer, foil or potting may comprise the conversion material comprising the first and second luminescent material, wherein the conversion material is arranged or applied on or above the layer sequence with an active area. A layer that the

Conversion material may continue from

Sub-layers or sub-areas are composed, wherein in the individual sub-layers or sub-areas

different composite conversion materials are present. The fact that an area "on" or "above" the layer sequence is arranged or applied with an active area, here and in the following mean that the

Conversion region is arranged directly in direct mechanical and / or electrical contact on the layer sequence with an active area. Furthermore, it can also mean that the conversion range is indirect

or is arranged above the layer sequence with an active area. In this case, further layers, areas and / or elements can then be arranged between the conversion area and the layer sequence.

In this case, one or more first and second phosphors in the conversion material can be homogeneous or with

Concentration gradients in a matrix material distributed or embedded. In particular, are suitable as

Matrix material Polymer or ceramic materials. The

Matrix material may be selected from a group comprising siloxanes, epoxies, acrylates, methyl methacrylates, imides, carbonates, olefins, styrenes, urethanes, their derivatives and mixtures, copolymers or compounds thereof, which compounds are in the form of monomers, oligomers or polymers can. For example, the matrix material may comprise or be an epoxy resin, polymethylmethacrylate (PMMA), polystyrene, polycarbonate, polyacrylate, polyurethane or a silicone resin such as polysiloxane or mixtures thereof.

According to a further embodiment, a potting may comprise the conversion material and a potting compound.

In addition, the potting may comprise one or more fillers. The potting can for example cohesively through the potting compound with the layer sequence with the active Be connected to the area. The potting compound can

for example, be polymeric material. In particular, it may be silicone, a methyl-substituted silicone, for example poly (dimethylsiloxane) and / or

Polymethylphenylsiloxane, a cyclohexyl-substituted

Silicone, for example poly (dicyclohexyl) siloxane, or a combination thereof.

Furthermore, the conversion material can additionally a

Filler, such as a metal oxide, such as

Titanium dioxide, zirconia, zinc oxide, alumina, a salt such as barium sulfate and / or glass particles. The degree of filling of the filler in, for example, the

Conversion material may be greater than 20% by weight, for example 25 to 30% by weight.

According to another embodiment, that is

Mixing ratio of the first phosphor and the second phosphor in the conversion material arbitrary selectable.

The electromagnetic primary radiation and secondary electromagnetic radiation may be one or more wavelengths and / or wavelength ranges in an infrared to

Ultraviolet wavelength range, in particular in a visible wavelength range. It can do that

Spectrum of the electromagnetic primary radiation and / or the spectrum of the electromagnetic secondary radiation

be narrowband, that is, the electromagnetic primary radiation and / or the electromagnetic

Secondary radiation a monochrome or approximate

monochrome wavelength range can have. The

Spectrum of the electromagnetic primary radiation and / or the spectrum of the electromagnetic secondary radiation can alternatively be broadband, that is, that the

electromagnetic primary radiation and / or the

Electromagnetic secondary radiation may have a mixed-colored wavelength range, wherein the mixed-color wavelength range may each have a continuous spectrum or a plurality of discrete spectral components with different wavelengths.

For example, the electromagnetic primary radiation can have a wavelength range from an ultraviolet to green wavelength range, while the secondary electromagnetic radiation can have a wavelength range from a blue to infrared wavelength range. Particularly preferably, the electromagnetic primary radiation and the secondary radiation superimposed on a white-colored

Create a luminous impression. For this purpose, the electromagnetic primary radiation can arouse a blue-colored luminous impression and the electromagnetic secondary radiation a

yellow-colored luminous impression caused by spectral components of the electromagnetic secondary radiation in the yellow

Wavelength range and / or spectral components in the green and red wavelength range can arise.

The optoelectronic component has, according to a further embodiment, a total emission, which consists of electromagnetic primary radiation and

composed of electromagnetic secondary radiation.

According to a further embodiment, the total emission of the optoelectronic component is white light. In particular, the total emission can be perceived as white light by an external observer during operation of the optoelectronic component. According to a further embodiment, the electromagnetic secondary radiation may consist of a first

electromagnetic secondary radiation emitted from the first phosphor and a second

Electromagnetic secondary radiation emitted from the second phosphor, put together. The first

Secondary electromagnetic radiation may have a wavelength selected from the range 490 nm to 575 nm, preferably 540 nm.

According to a further embodiment, the first

electromagnetic secondary radiation a wavelength

which range from 515 nm to 560 nm,

For example, 530 nm is selected.

According to one embodiment, the second

electromagnetic secondary radiation a wavelength

which is selected from the range 600 nm to 750 nm, preferably 630 nm. The first phosphor thus emits in the yellow or green spectral range of the electromagnetic radiation and the second phosphor in the orange or red spectral range of the electromagnetic radiation.

The conversion material has an absorption spectrum and an emission spectrum, wherein the absorption spectrum and the emission spectrum are advantageously at least partially not congruent. Thus, the absorption spectrum may at least partially comprise the spectrum of the electromagnetic primary radiation and the emission spectrum at least partially the spectrum of the electromagnetic secondary radiation. It is therefore due to the conversion material

at least partially from electromagnetic primary radiation generates an electromagnetic secondary radiation. In accordance with at least one embodiment, the conversion material further comprises at least one dye.

In particular, for producing a conversion material, which is formed, for example, layer-shaped, the first and second phosphors can be applied in liquid form. Optionally, the first and second phosphors may be mixed with a matrix material, which may also be in a liquid phase, and co-applied. Optionally, the liquid matrix material and the first and second phosphors, for example, on the

Layer sequence are applied to the active area. An electrode can also be applied to the layer sequence and first and second phosphors, which are optionally mixed with a matrix material, are applied in layers to this electrode. By drying and / or crosslinking processes, the first and second phosphors or the mixture can be cured and / or fixed and the

layered shaped conversion material are formed.

According to one embodiment, the second phosphor, for example of the type M2Si5Ng, where M is a combination of

Ca, Sr, Ba and Eu are prepared as follows:

Starting substances are weighed in stoichiometrically. If alkaline earth metal components are used for M, they can also be weighed in excess so that they can eventually be used

Compensate for evaporation losses during the synthesis. Starting substances can be selected from a group comprising alkaline earth metals and their compounds, silicon and its compounds, and europium and its compounds. This may be alkaline earth metal compounds Alloys, hydrides, silicides, nitrides, halides, oxides and mixtures of these compounds. Silicon compounds can be made of silicon nitrides,

Alkaline earth silicides, Siliciumdiimiden, silicon hydrides or mixtures of these compounds can be selected. Preferably, silicon nitrides and silicon metal are used which are stable, readily available and inexpensive. Compounds of europium may consist of europium oxides, europium nitrides,

Europium halides, europium hydrides or mixtures of these compounds. Preferably, europium oxide is used which is stable, readily available and inexpensive.

It can also be a flux for the improvement of

Crystallinity and in support of the crystal growth of the phosphor can be used. Here, the chlorides and fluorides of the alkaline earth metals used, such as SrCl ₂ , SrF ₂ , CaCl ₂ , CaF ₂ , BaCl ₂ , BaF ₂ , halides, such as NH ₄ Cl, NH ₄ F, KF, KCl, MgF ₂ , and boron-containing compounds , such as H ₃ BO ₃ , B ₂ 0 ₃ , Li ₂ B ₄ 0 ₇ , NaB0 ₂ , Na ₂ B ₄ 0 ₇ , are used.

Alternatively, charge-neutral substitution of the SiN units in the second type M2Si5Ng phosphor is accomplished

AlO units possible. The starting substances are mixed, wherein the mixture of the starting substances is preferably carried out in a ball mill or in a tumble mixer. In the mixing process, the conditions can be chosen so that sufficient energy is introduced into the mix, resulting in a milling of the starting materials. The increased with it

Homogeneity and reactivity of the mixture can have a positive influence on the properties of the resulting

Have fluorescent. By deliberately changing the bulk density and / or by modifying the agglomeration of the starting material mixture, the formation of secondary phases can be reduced.

In addition, the particle size distribution,

Particle morphology and the yield of the resulting second phosphor can be influenced. The one for this

suitable techniques include screenings and

Granulate, optionally using appropriate

Additions .

Subsequently, the mixture can be tempered once or several times. The tempering can be carried out in a crucible made of tungsten, molybdenum or boron nitride. The heat treatment takes place in a gas-tight oven in a nitrogen or

Nitrogen / hydrogen atmosphere. The atmosphere can be fluid or stationary. It may also be advantageous for the quality of the second phosphor when carbon is present in finely divided form in the furnace chamber. Multiple anneals of the second phosphor can the

Crystallinity or the particle size distribution further

improve. Other benefits may be lower

Defect density combined with improved optical

Be properties of the second phosphor and / or higher stability of the second phosphor. Between

Temperings, the second phosphor can be treated or it can the second phosphor substances, such as

Starting substances, flux, other substances or a mixture of these substances are added. The annealed phosphor can still be ground. For the grinding of the second phosphor can usual

Tools, such as a mortar mill, a

Fluidized bed mill, or a ball mill can be used. at The grind should be kept as low as possible, the proportion of generated splitter grain, since this is the optical properties of the second phosphor

can worsen.

Subsequently, the second phosphor can be additionally washed. For this purpose, the phosphor in water or in

aqueous acids such as hydrochloric acid, nitric acid, hydrofluoric acid, sulfuric acid, organic acids or a mixture of these. As a result, secondary phases, glass phases or other impurities can be removed and thus an improvement in the optical properties of the second phosphor can be achieved. It is also possible to trigger by this treatment specifically smaller phosphor particles and the

Optimize particle size distribution for the application. Furthermore, it is possible to use the second phosphor in

Particle form, whereby by treatment the

Surfaces of the particles can be selectively changed, such. the removal of certain components from the

Particle surface. This treatment may, possibly in

Associated with a downstream treatment, lead to improved stability of the phosphor.

In one embodiment, the first phosphor having the composition A ₃ B ₅ O ₁ 2 may be prepared as follows.

First, starting substances of component A

provided that are selected from a group

Rare earth metal oxides, rare earth metal hydroxides and

Rare earth metal salts such as

Rare earth carbonates, rare earth nitrates,

Rare earth metal halides, and combinations thereof. As starting materials of component B, oxides,

Hydroxides or salts of aluminum, such as theirs Carbonates, nitrates, halides or combinations of said compounds can be selected.

In addition to the starting materials flow or

Fluxes, such as, but not limited to, fluorides such as NH ₄ HF ₂ , LiF, NaF, KF, RbF, CsF, BaF ₂ , AlF ₃ , CeF ₃ , YF ₃ , LuF ₃ , GdF ₃ , and similar compounds, or boric acid, and their salts. Furthermore, any combination of two or more of the above-mentioned fluxes come into question.

The starting substances and optionally the melting and fluxing agents are homogenized, for example in a mortar mill, a ball mill, a turbulent mixer, a plowshare mixer or by other suitable methods. The homogenised mixture is then subjected to reduction in an oven, for example a tube furnace, a chamber furnace or a push-through oven, for several hours

Atmosphere annealed for several hours. The material to be annealed is then ground, for example in a mortar mill, ball mill, fluidized bed mill or other types of mill. The milled powder is then subjected to further fractionation and classification steps, such as sieving, flotation or sedimentation and optionally washed. The reaction product comprises the first phosphor.

Alternatively, the first and second phosphors, and optionally a matrix material can also be vapor-deposited and then cured by crosslinking reactions.

Furthermore, the particles of the first and / or second phosphor can at least partially the electromagnetic

Scatter primary radiation. This allows the first and second Phosphor simultaneously as a luminous center, which partially absorbs the radiation of the electromagnetic primary radiation and emits a secondary electromagnetic radiation, and be designed as a scattering center for the primary electromagnetic radiation. The scattering properties of the conversion ^¬ material can lead to improved radiation extraction from the device. The scattering effect can ^¬ example, also lead to an increase in the probability of absorption of primary radiation in the conversion material, thus a smaller layer thickness of the layer containing the conversion material, may be required.

In addition, the conversion material may also be applied to a substrate comprising, for example, glass or a transparent plastic, wherein on the

Conversion material, the layer sequence with the active

Can be arranged area.

According to a further embodiment, the optoelectronic component may have an encapsulation enclosing the layer sequence with the active region, wherein the

Conversion material in the beam path of the electromagnetic primary radiation can be arranged inside or outside the encapsulation. The encapsulation can each as

Thin-layer encapsulation be executed.

According to one embodiment, the conversion material is in direct contact with the radiation source. So can the

Conversion of the electromagnetic primary radiation in the electromagnetic secondary radiation at least partially near the radiation source, for example at a distance

Converter material and radiation source of smaller or equal to 200 ym, preferably less than or equal to 50 ym done (so-called "chip-level conversion").

According to one embodiment, the conversion material is spaced from the radiation source. Thus, at least in part, the conversion of the electromagnetic primary radiation into the electromagnetic secondary radiation takes place at a large distance from the radiation source, for example in one

Distance converter material and radiation source of greater than or equal to 200 ym, preferably greater than or equal to 750 ym, more preferably greater than or equal to 900 ym (so-called "remote phosphor conversion").

According to one embodiment, the conversion material may in particular be embedded as a volume encapsulation in a matrix material.

Further advantages and advantageous embodiments and

Further developments of the subject invention will become apparent from the embodiments described below in connection with the figures.

The figures show:

Figure 1 is a schematic side view of a

optoelectronic component,

Figure 2 shows a phosphor spectrum at different

Emission wavelengths according to an embodiment, and

Figure 3 shows an aging of a second phosphor and a

Comparative Example. FIG. 1 shows a schematic side view of a

Optoelectronic component on the embodiment of a light emitting diode (LED). The optoelectronic component has a layer sequence 1 with an active region (not explicitly shown), a first electrical connection 2, a second electrical connection 3, a bonding wire 4, a potting 5, a housing wall 7, a housing 8, a recess 9, a first phosphor 6-1, a second phosphor 6-2 and a matrix material 10.

Furthermore, the layer sequence 1 can be arranged with an active region on a carrier (not shown here). For example, a carrier may be a printed

Circuit board (PCB), a ceramic substrate, a circuit board or an aluminum plate act.

Alternatively, a carrierless arrangement of the layer sequence 1 in so-called thin-film chips is possible. The active area is electromagnetic for emission

Primary radiation in a direction of emission suitable. The

Layer sequence 1 with an active area can

For example, based on nitride compound semiconductor material. Nitride compound semiconductor material emits in particular electromagnetic primary radiation in the blue and / or ultraviolet spectral range.

The first phosphor 6-1 and second phosphor 6-2, which are present in particle form as shown here, are embedded in a matrix material 10 in the beam path of the electromagnetic primary radiation. The matrix material 10 is for example polymer or ceramic material. In this case, the first phosphor 6-1 and / or the second phosphor 6-2 arranged directly in direct mechanical and / or electrical contact on the layer sequence 1 with an active region. Alternatively, further layers and materials, such as, for example, the encapsulation, may be arranged between the first phosphor 6-1 and / or second phosphor 6-2 and the layer sequence 1 (not shown here). Alternatively, the first phosphor 6-1 and second

Phosphor 6-2 be arranged directly or indirectly on the housing wall 7 of a housing 8 (not shown here).

Alternatively, it is possible that the first phosphor 6-1 and the second phosphor 6-2 are embedded in a potting compound (not shown here), and together with the

Matrix material 10 are formed as encapsulation 5.

First phosphor 6-1 and second phosphor 6-2

at least partially convert the electromagnetic

Primary radiation in an electromagnetic secondary radiation. For example, the electromagnetic primary radiation is emitted in the blue spectral range of the electromagnetic radiation, wherein at least a portion of this electromagnetic see primary radiation from the first phosphor 6-1 and the second phosphor 6-2 to a first secondary electromagnetic radiation in the green and a second secondary electromagnetic radiation in the red Spectral range of electromagnetic radiation is converted. The total radiation emerging from the opto-electronic component is a superimposition of blue-emitting primary radiation and red and green-emitting secondary radiation, wherein the radiation for the external observer visible total emission is white light.

FIG. 2 shows the intensity in a.U. a first

Phosphor having the composition (yi_ _y Ce _y) 3AI5O ₁ 2 with y = 0.035 and a second phosphor having the composition (Sr _0, ₃₆ Bao, ₅ Cao, iEuo, o4) ₂ Si _{5 8} in an optoelectronic

Component as a function of the emission wavelength in nm at a color temperature of 2988K and a

Color Rendering Index (CRI) of 79. The first and second phosphors are combined with a

Electromagnetic primary radiation of 465 nm excited, the figure 2 shows the total emission of the optoelectronic component of electromagnetic primary radiation and electromagnetic secondary radiation. The first

Emission band with a maximum wavelength of 460 ± 5 nm shows the emission of primary electromagnetic radiation, the second emission band with a maximum wavelength of about 600 nm from a superposition of the emission band of the first phosphor with a maximum wavelength of about 555 nm and the emission band of the second phosphor with a maximum wavelength of about 630 nm results. The

Total emission of the optoelectronic component gives (warm) white light. By the combination of

electromagnetic primary radiation with first and second

Phosphor results for the optoelectronic component, a long-term stability relative to relative humidity and improved thermal stability compared to conventional systems, for example, instead of the second phosphor according to the invention a phosphor of the type (Sr, Ca) i_ _z AlSiN ₃ : Eu _z with 0, 003 < z <0, 007.

For example, at z = 0.007, the Sr content is 69.51 mol% and the Ca content is 29.79 mol% in a phosphor of the type (Sr, Ca) AlSi ₃ i_ _z: Eu _z. Despite the relatively long wavelength of the electromagnetic primary radiation, the first

Phosphor be excited efficiently due to the location of its absorption maximum in the wavelength range of 450 to 470 nm.

Here and below, the following abbreviations for exemplary embodiments and comparative examples of

Phosphors used:

AI: embodiment of a second phosphor having the composition (Sr ₀ , 36 Baao, 5 Cao, iEuo, o4) 2SisN ₈

VI: Comparative Example (Sr, Ca) AlSiN ₃ i_ _z: Eu _z with 0, 003 <z <0, 007. Figure 3 shows an aging D in percent AI and VI. The

Aging D was calculated from the ratio of the radiation energy of AI and VI after 0 hours and the

Radiation energy of AI or VI determined after 168 h. A so-called Pressure Cooker Test (PCT) was carried out over a period of 168 hours at 121 ° C, a pressure of about 2 atm, a relative humidity of 100% and a current of 20 mA. AI and VI are each a high water vapor pressure, a high

Temperature and / or relative humidity in an autoclaved chamber exposed to the ability and

To assess reliability of VI and AI under extreme conditions. Comparative Example VI shows a larger aging compared to the embodiment AI. As a result, the embodiment AI is more stable in the long term than VI against high temperature, high water vapor pressure and / or high relative humidity. The stability of AI is intrinsic, meaning that AI is of is stable out and not by subsequent

Treatment needs to be stabilized.

The invention is not limited by the description with reference to the embodiments. Rather, the includes

Invention every new feature as well as every combination of

Features, which includes in particular any combination of features in the claims, even if this feature or this combination itself is not explicitly in the

Claims or embodiments is given.

This patent application claims the priority of German Patent Application 10 2012 101920.7, the disclosure of which is hereby incorporated by reference.

Claims

Comprising an optoelectronic component

a layer sequence (1) having an active region which emits electromagnetic primary radiation;

a conversion material in the beam path of the

electromagnetic primary radiation is arranged and at least partially the electromagnetic

Primary radiation in an electromagnetic

Converted secondary radiation,

wherein the conversion material comprises a first phosphor (6-1) having the general composition A ₃ B ₅ O ₁ 2 and a second phosphor (6-2) having the general composition M ₂ S ₅ N ₈ , where A is one of

Elements Y, Lu, Gd and / or Ce or combinations of Y, Lu, Gd and / or Ce, where B is AI,

wherein in the second phosphor (6-2) Ca as part of

Component M is present in a proportion of 2.5 mol% to 25 mol%,

wherein the component M of the second phosphor (6-2) contains Ba in a proportion greater than or equal to 40 mol%, wherein the component M of the second phosphor (6-2) Eu in a proportion of 0.5 mol% to 10 mol%, and wherein the component M of the second phosphor (6-2) contains Sr.

An optoelectronic component according to claim 1, wherein said second phosphor (6-2) (Sr ₀ , ₃₆ Bao, ₅ Cao, iEuo, o4) _{2 is} SisN ₈ .

Optoelectronic component according to one of

previous claims,

wherein the electromagnetic primary radiation a

Wavelength in the range 445 nm to 565 nm.

4. Optoelectronic component according to claim 3,

wherein the electromagnetic primary radiation a

Wavelength in the range 450 nm to 470 nm.

5. Optoelectronic component according to one of

preceding claims, wherein the

secondary electromagnetic radiation from a first secondary electromagnetic radiation emitted by the first phosphor (6-1) and a second secondary electromagnetic radiation emitted by the second phosphor (6-2),

composed.

6. Optoelectronic component according to one of

previous claims, wherein the first

electromagnetic secondary radiation has a wavelength i range 490 nm to 575 nm.

7. Optoelectronic component according to claim 6,

wherein the first secondary electromagnetic radiation has a wavelength in the range 515 nm to 560 nm.

8. Optoelectronic component according to one of

previous claims, wherein the second

electromagnetic secondary radiation has a wavelength i range 600 nm to 750 nm.

9. Optoelectronic component according to one of

preceding claims, wherein in the first

Phosphor (6-1) Ce is present as component A in a proportion of 0.5 mol% to 5 mol%.

10. Optoelectronic component according to one of

preceding claims, wherein in the first

Phosphor (6-1) Y is present as component A in a proportion of 95 mol% to 99.5 mol%.

11. Optoelectronic component according to one of

preceding claims, which has a total emission resulting from electromagnetic

Primary radiation and electromagnetic

Secondary radiation is composed.

12. Optoelectronic component according to one of

preceding claims, wherein the total emission of the optoelectronic device is white light.