WO2009039816A1

WO2009039816A1 - Radiation-emitting component having glass cover and method for the production thereof

Info

Publication number: WO2009039816A1
Application number: PCT/DE2008/001451
Authority: WO
Inventors: Stefan GRÖTSCH; Thomas Schreiber; Mathias KÄMPF
Original assignee: Osram Opto Semiconductors Gmbh
Priority date: 2007-09-27
Filing date: 2008-09-02
Publication date: 2009-04-02
Also published as: KR20100063130A; DE102007046348A1; CN101809766A; TW200915630A

Abstract

The invention relates to a component comprising at least one LED chip (1), which is disposed on a carrier substrate (2), and a radiation-permeable glass cover (3), which is applied to the carrier substrate (2) and has a cavity (6) suited to receive the at least one LED chip (1). The glass cover (3) is disposed at a distance from the LED chip (1) such that an intermediate space (7) is created between the at least one LED chip (1) and the glass cover (3), said intermediate space being free of solid and liquid materials. The invention further relates to a method for producing a radiation-emitting component.

Description

description

Radiation-emitting device with glass cover and method for its production

The invention relates to a radiation-emitting component with a glass cover according to claim 1. Furthermore, the invention relates to a method for producing such a radiation-emitting component according to claim 19.

This patent application claims the priority of German patent application 10 2007 046 348.2, the disclosure of which is hereby incorporated by reference.

Radiation-emitting components with a cover are known, for example, from document WO 97/50132. These arrangements include a body defining a recess covered by a plastic cover plate. The bottom of this recess is intended for the mounting of a diode chip. An example of a device having such a body is disclosed in US 5,040,868.

For many applications, the radiation intensity of a single radiation-emitting diode chip is not sufficient, but a plurality of chips is required. The assembly of several chips in the body provided for mass production is not common, difficult to implement and expensive because of the large required chip area. The covers of the base body of thermoplastic optics are usually applied individually to the body. Furthermore, it is disclosed in WO 01/65613 A1 to apply a thin conversion layer having at least one conversion element directly on a semiconductor layer sequence of a diode chip.

Such a conversion of the light through a thin conversion layer directly above the semiconductor body has the consequence that the coupling-out efficiency of the semiconductor body through the conversion layer can change and the color locations can exhibit fluctuations.

For the purposes of the invention, the "color locus" defines the numerical values which describe the color of the emitted light of the component in the CIE standard color chart.

In addition, color differences over the emission angle may also occur due to different path lengths of the radiation.

The invention has for its object to provide a radiation-emitting device with improved luminance and a method for its production.

This object is achieved by a radiation-emitting component with the features of claim 1 and by a method for its production according to claim 19. Advantageous embodiments and preferred developments of the device are the subject of the dependent claims.

According to the invention, it is provided that the radiation-emitting component has a carrier substrate, at least one LED chip applied to this carrier substrate, and an applied on the carrier substrate radiation-transparent glass cover, which contains at least one cavity which is suitable to receive at least one LED chip. In this case, the glass cover is arranged at a distance from the LED chip, so that there is a gap between the at least one LED chip and the glass cover, which is free of solid and liquid matter.

For this purpose, the cavity of the glass cover is formed to receive at least one LED chip and to enclose a gap between the at least one LED chip and the glass cover. The glass cover therefore has no direct contact with the LED chip.

Characterized in that a gap between the LED chip and the glass cover is present, which is free of solid and liquid matter, the chip in particular has no potting, improves the luminance of the device. Furthermore, the glass cover serves to protect the LED chip from damage, for example due to shocks.

The glass cover is preferably arranged on the carrier substrate such that it encloses the at least one LED chip together with the latter. In other words, the carrier substrate and the glass cover completely enclose the cavity in which the at least one LED chip is arranged.

The glass cover preferably represents a single coherent, one-piece component. Preferably, the glass cover is designed as a separately produced body, which is adapted to the carrier substrate. According to at least one embodiment of the invention, the gap between the glass cover and the LED chip contains air.

Advantageously, in non-cast LED chips based on a nitride compound semiconductor and disposed in air, it is preferred that luminances be about 15 percent higher than conventional, potted LED chips based on a nitride compound semiconductor.

"Based on nitride compound semiconductors" in the present context means that the active epitaxial layer sequence or at least one layer thereof is a nitride III / V compound semiconductor material, preferably

Al _n Ga _1n IrIi - _J1 - _H1 N, where O ≤ n ≤ l, 0 <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. Rather, it may have one or more dopants and additional ingredients which do not change the characteristic physical properties of the Al _n Ga _m ini- _n -mn material substantially. 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 may be partially replaced by small amounts of other substances.

In at least one further embodiment, the radiation exit side of the at least one LED chip faces the glass cover. Thus, the decoupling of the electromagnetic radiation in the component is preferably carried out essentially by the glass cover ("top emitter"). The carrier substrate therefore does not need to be transparent or partially transparent, which preferably results in a larger choice of material for the carrier substrate. For example the carrier substrate is a substrate which preferably comprises ceramic, silicon or epoxy resin. Improved temperature resistance can be achieved by fillers such as glass fibers.

Preferably, a conversion layer is applied on at least one main surface of the glass cover, which has at least one conversion substance which converts at least a portion of a primary radiation emitted by the LED chip into secondary radiation, at least a portion of the secondary radiation and a portion of the unconverted primary radiation becoming one Overlay mixed radiation. Particularly preferably, the conversion layer is applied to a main surface of the cavity of the glass cover. In this case, the conversion layer can be applied to a main surface of the cavity of the glass cover, which faces away from the LED chip or faces the LED chip.

This has the advantage that the decoupling properties of the LED chip change less than with LED chips that are directly coated with a conversion layer. Un-cast LED chips have a higher coupling-out efficiency than LED chips, which are directly coated with the conversion layer. This can result in about 10 percent higher luminance.

Alternatively, the conversion substance which converts at least part of a primary radiation emitted by the LED chip into a secondary radiation, wherein at least part of the secondary radiation and a part of the unconverted primary radiation overlap to form a mixed radiation, can be introduced directly into the glass cover. It's special advantageous to bring the conversion substance in the glass cover, as not only an increased, but also a particularly homogeneous emission characteristics can be achieved.

In at least one advantageous embodiment of the invention, at least one further conversion substance, which is contained in at least one conversion layer, is applied to a main surface of the glass cover. In this case, the at least one further conversion substance converts the primary radiation emitted by the LED chip into a further secondary radiation, so that the component mixed radiation, consisting of primary radiation, secondary radiation of the first

Conversion substance, which is located directly in the glass cover or in a conversion layer on a main surface of the glass cover, and emits secondary radiation of the further conversion layer or other conversion layers. Thereby, it is advantageously possible to produce a variety of color mixtures and color locations.

If a first conversion layer is applied to one main surface of the glass cover, the further conversion layer or conversion layers can be applied to a further main surface of the glass cover and / or directly to the first conversion layer.

In the invention, it is provided that the wavelength range (s) of the secondary radiation of the first and / or further conversion substances have substantially longer wavelengths than the wavelength range of the primary radiation. Preferably, conversion substance or conversion substances and LED chip are matched to one another such that the colors of the primary light and at least part of the secondary light are complementary to one another. Additive color mixing gives the impression of white light.

Preferably, the first and / or further

Conversion layer on the glass cover a constant thickness. This results in a unified path length of the radiation within the conversion layer. This advantageously leads to a homogenization of the color impression of the radiation-emitting component.

Particularly preferably, the respective conversion substance is substantially homogeneously distributed in the first and / or further conversion layer and / or in the glass cover. A substantially homogeneous distribution of the conversion substance advantageously leads, as a rule, to a very homogeneous emission characteristic and to a very homogeneous color impression of the radiation-emitting component. The expression "substantially homogeneous" in the present context means that the particles of the conversion substance are distributed so uniformly in the respective conversion layer and / or the glass cover, as is possible and useful within the scope of technical feasibility.

In at least one preferred embodiment, the glass cover completely covers the carrier substrate in a plan view of the carrier substrate. Particularly preferably, the carrier substrate and the glass cover are arranged flush with each other in plan view of the substrate. That is, the support substrate and the glass cover are in plan view the main extension plane is the same extent and congruent.

Preferably, the glass cover has a thickness of between 50 μm and 500 μm inclusive.

The carrier substrate preferably contains ceramic, silicon or FR4. The glass cover particularly preferably contains a borosilicate glass, for example Pyrex, and the carrier substrate silicon.

The carrier substrate preferably has a reflector layer for the primary radiation emitted by the LED chip during operation with the highest possible reflection coefficient (possibly by suitable coating of the main surface of the carrier substrate facing the LED chip), so that the primary radiation of the LED chip in the direction the glass cover is reflected.

Particularly preferably, the LED chip has a metallic layer with good reflection properties for the radiation emitted by the LED chip.

In the invention, the wavelength of the radiation emitted by the LED chip is preferably in the blue spectral range. In particular, LED chips based on nitride compound semiconductors are suitable for this purpose. Under

Nitride compound semiconductors are in particular semiconductors which contain a nitride compound of elements of the third main group of the Periodic Table of the chemical elements such as GaN, ^' AlN, InN, InGaN, AlGaN or AlInGaN. The active layer sequence of the LED chip preferably comprises a pn junction, a double heterostructure, a single quantum well or particularly preferably a multiple quantum well structure (MQW) for generating radiation. The term quantum well structure does not contain any information about the dimensionality of the quantization. It thus includes quantum wells, quantum wires and quantum dots and any combination of these structures.

In a preferred embodiment of the invention, which is particularly suitable for producing mixed-colored light, the secondary radiation of the conversion substance of the first and / or second conversion layer and / or the conversion substance in the glass cover is in the yellow or red spectral range. In this way, a radiation-emitting component is achieved which emits mixed radiation having a color locus in the white region of the CIE standard color chart.

The LED chip is with particular advantage a thin-film LED chip. In the context of the application, an LED chip is considered a thin-film light-emitting diode chip, during the manufacture of which the growth substrate on which a layer sequence for the LED chip has been grown, for example epitaxially, is thinned or, in particular, completely detached.

A basic principle of a thin-film light-emitting diode chip is described, for example, in I. Schnitzer et al. , Appl. Phys. Lett. 63 (16), 18 October 1993, 2174-2176, the disclosure content of which is hereby incorporated by reference. Preferably, an antireflection layer is applied to the main surface of the glass cover facing the LED chip. Particularly preferred is additionally on the remote main surface of the glass cover another

Antireflection layer applied. As a result, the luminance of the component improves further advantageous.

By means of a solder or adhesive layer arranged between the carrier substrate and an edge region of the glass cover, the glass cover is expediently connected in a mechanically stable manner to the carrier substrate. Preferably, the solder or adhesive layer is substantially impermeable to water and oxygen or other oxidizing substances. For example, an adhesive layer based on epoxy resin is used.

In at least one further embodiment, a plurality of LED chips is applied to the carrier substrate. In this case, the glass cover may have exactly one cavity, so that the carrier substrate and the glass cover exactly enclose a gap in which the plurality of LED chips is arranged. Alternatively, the glass cover may have a plurality of cavities, each cavity being designed to receive one LED chip each. Thus, the carrier substrate and the glass cover completely enclose a plurality of gaps, in each of which exactly one LED chip is arranged. The glass cover is formed as a continuous, one-piece cover.

A method according to the invention for producing a radiation-emitting component comprises in particular the following steps: a) providing a carrier substrate; b) applying at least one LED chip on the carrier substrate; c) electrical contacting of the at least one LED chip with connection points of the carrier substrate; d) producing a glass cover and forming the glass cover by deep drawing, so that the glass cover has at least one cavity for receiving the at least one LED chip; e) applying the glass cover to the carrier substrate by means of a solder or adhesive layer.

The method advantageously makes it possible to provide a radiation-emitting component with improved luminance and a radiation-emitting component suitable for mass production with a separately produced glass cover.

The substrate is expediently in the form of a plate. Preferably, a first electrode is deposited on the substrate. In the production of a plurality of components by the method, a first electrode layer is deposited in a structured manner or deposited over the whole area and patterned after deposition to form individual first electrodes.

An LED chip is applied to the first electrode. Methods for mounting LED chips on a carrier substrate provided with first contact connections are known to the person skilled in the art and are therefore not explained in greater detail here. For further contacting of the LED chips preferably electrical conductor tracks are deposited on the plate. These are connected to the connection point of the LED chip by means of a bonding wire or by means of an electrically conductive layer, which is deposited along a side surface of the LED chip from the connection point of the LED chip to the printed conductors deposited on the carrier substrate. These methods for making electrical contact with the LED chips are known to the person skilled in the art and are therefore not explained in detail at this point.

To cover the carrier substrate and the LED chips mounted thereon, a separately made, continuous glass cover, preferably having a thickness of between 50 μm and 500 μm inclusive, is produced. To produce the cavity, which is suitable for accommodating at least one LED chip, the glass plate is shaped by means of deep drawing.

Subsequently, the glass cover is applied to the carrier substrate. The glass cover preferably completely covers the side of the carrier substrate facing the LED chip.

On the surface facing the LED chip or / and the surface of the glass cover facing away from the LED chip, at least one conversion layer can be applied, in particular in the region of the cavity. Alternatively, the conversion layer or the conversion layers can be evaporated on the glass or the conversion substance can be melted into the glass. Particularly preferred is on the at least one LED chip facing and / or facing away Surface of the glass cover applied at least one antireflection coating.

In at least one further embodiment, a plurality of LED chips are applied to the carrier substrate and a coherently produced glass cover is applied over the plurality of LED chips, wherein the glass cover has a plurality of cavities for accommodating in each case one LED chip. The glass cover preferably represents a single coherent, one-piece structure. Particularly preferably, the glass cover completely covers the side of the carrier substrate facing the LED chips.

In the production of the component with a plurality of LED chips, at least one conversion layer can preferably be applied to at least one surface of the glass cover, in particular in the region of the cavity. Alternatively, the conversion layer or the conversion layers can be evaporated on the glass or the conversion substance can be melted into the glass. Particularly preferably, at least one antireflection layer is applied to at least one surface of the glass cover.

This has the advantage that in the production of the component with a plurality of LED chips with the inventive method exactly one coherent and separately manufactured, one-piece glass cover is antireflection-coated, and thus reduce the production time and production costs.

The connection of the carrier substrate to the glass cover is preferably effected by means of an adhesive layer which is applied to the substrate and / or the glass cover, preferably in the form of a Glue bead, applied in places. The adhesive layer is preferably a thermally curable adhesive, for example based on an epoxy resin. The curing takes place for example by heating and / or by irradiation with electromagnetic radiation, in particular in the infrared and / or ultraviolet spectral range. The electromagnetic radiation is particularly preferably laser radiation. The electromagnetic radiation is preferably focused and / or shadowed in places, so that preferably substantially only the adhesive-covered areas of the carrier substrate and / or the glass cover are irradiated.

Due to the material combination of the radiation-emitting component, only the conversion layer, which preferably contains silicone, and the connection material, which preferably contains an adhesive, a solder or a glass solder, are temperature-limiting. The production of the radiation-emitting component can thus take place at temperatures up to 180 ^° C.

In at least one preferred embodiment of the composite comprising the carrier substrate, the plurality of LED chips and the ^'one-piece cover glass is singulated into individual radiation-emitting components by means of sections which cut through both the carrier substrate and the one-piece glass cover. At the same time, the cuts can also structure the first electrode layer to form individual first electrodes. The method thus advantageously allows a simple separation of the composite into individual components by means of straight cuts. Alternatively, the glass cover, which preferably has at least one conversion substance on at least one surface or in the glass plate, can be separated before being applied to the carrier substrate equipped with a plurality of LED chips. Preferably, the radiation characteristics of the at least one applied conversion substance or conversion substances of the individual glass covers and the emission characteristics of the individual LED chips mounted on the carrier substrate are then measured separately. Subsequently, the individual glass covers are combined with the LED chips mounted on the carrier substrate in a sorting process in such a way that a desired chromaticity control takes place and is mounted over the LED chips.

The specific combination of the individual LED chips with the individual glass covers, which contain at least one conversion layer, has the advantage that a desired color location of the radiation-emitting component can be set. This allows a largely reproducible component characteristic.

Further features, advantages, preferred embodiments and expediencies of the component emerge from the exemplary embodiments explained below in conjunction with FIGS. 1, 2 and 3. Show it:

FIG. 1 shows a schematic cross section of a first exemplary embodiment of a component according to the invention,

FIG. 2 shows schematic plan views of a plurality of radiation-emitting components according to a further exemplary embodiment, and Figure 3 shows schematic cross sections through a plurality of radiation-emitting components at different stages according to an embodiment of the method according to the invention.

The same or equivalent components are each provided with the same reference numerals. The illustrated components as well as the size ratios of the components with each other are not necessarily to be considered as true to scale.

In the radiation-emitting component shown in FIG. 1, two LED chips 1 based on GaN are arranged on a carrier substrate 2. Alternatively, a multiplicity of LED chips 1 can also be arranged on the carrier substrate 2.

The carrier substrate 2 has contact terminals (not shown) on which the LED chips are arranged. For further contacting of the LED chips, electrical conductor tracks are preferably deposited on the carrier substrate 2 (not shown). These can be connected to connection points of the LED chips by means of a bonding wire or by means of an electrically conductive layer which is applied along a side surface of the LED chip 1 from the connection point of the LED chip 1 to the printed conductors 2 deposited on the carrier substrate 2 (not shown) ).

The support substrate 2 and the LED chips 1 mounted thereon are of a glass cover 3 having a thickness between including 50 microns and including 500 microns, covered.

By means of a solder or adhesive layer 9 arranged between the carrier substrate 2 and an edge region of the glass cover 3, the glass cover 3 is expediently connected in a mechanically stable manner to the carrier substrate 2. Preferably, the solder or adhesive layer 9 is substantially impermeable to water and other oxidizing substances. For example, an adhesive layer based on epoxy resin is used.

The glass cover 3 preferably completely covers the carrier substrate 2 in a plan view of the carrier substrate 2. Particularly preferably, the carrier substrate 2 and the glass cover 3 are arranged flush with one another in plan view of the substrate 2. That is, the support substrate 2 and the glass cover 3 have the same extension in plan view of the main extension plane and are congruent.

The glass cover 3 includes a cavity 6 adapted to receive the LED chips 1. For this purpose, the cavity of the glass cover is formed so as to include a space 7 between the LED chips 1 and the glass cover 3, which is free of solid and liquid matter and preferably contains air. Accordingly, the glass cover 2 has no direct contact with the LED chip 1.

The glass cover 3 is preferably arranged on the carrier substrate 2 in such a way that it encloses the LED chips 1 together with the latter. In other words, that includes Carrier substrate 2 and the glass cover 3 an interior space in which the LED chips are arranged completely.

The glass cover 3 preferably represents a single coherent, one-piece component. Preferably, the glass cover 3 is formed as a separately produced body, which is adapted to the carrier substrate 2.

LED chips 1 show the highest luminance and brightness without potting. Advantageously, the luminance of the device improves in that a gap 7 between the LED chips 1 and the glass cover 3 is present, which is free of solid and liquid matter and preferably contains air. The luminance increases compared to potted LED chips advantageous by about 15 percent. Furthermore, the glass cover 3 serves to protect the LED chips 1 from damage, for example due to shocks.

The radiation exit sides of the LED chips 1 face the glass cover 3. Thus, the decoupling of the electromagnetic radiation in the component preferably takes place essentially through the glass cover 3 ("top emitter"). The carrier substrate 2 therefore does not need to be transparent or partially transparent, which preferably results in a larger choice of material for the carrier substrate 2. The carrier substrate 2 preferably contains silicon and the glass cover 3 contains a borosilicate glass, for example Pyrex. Alternatively, the carrier substrate 2 may be a substrate which preferably comprises a ceramic, silicon or epoxy resin. Improved temperature resistance can be achieved by fillers such as glass fibers. Conversion layers 4 are preferably applied to the main surfaces 5 of the glass cover 3. The conversion layers 4 each contain a conversion substance that converts at least a portion of a primary radiation emitted by the LED chips 1 into a secondary radiation. A part of the unconverted primary radiation, a part of the secondary radiation of the first conversion layer and a part of the secondary radiation of the second conversion layer are superimposed to form a mixed radiation, wherein the component preferably emits white light.

This has the advantage that the decoupling properties of the LED chips 1 change less than with LED chips which are coated directly with a conversion layer 4. Unvergossene LED chips 1 have about 10 percent higher luminance than LED chips that are coated directly with the conversion layer 4.

Alternatively, the conversion substance 4 may be incorporated in the glass cover 3 (not shown). It is particularly advantageous to introduce the conversion substance 4 in the glass cover 3, since not only an increased, but also a particularly homogeneous radiation characteristic can be achieved.

The conversion layers 4 preferably have a constant thickness on the glass cover 3. This results in a unified path length of the radiation within the conversion layers 4. This advantageously leads to a homogenization of the color impression of the radiation-emitting component. Preferably, the conversion substance is in each case distributed homogeneously in the conversion layers 4. A homogeneous distribution of the conversion substance 4 advantageously leads, as a rule, to a very homogeneous emission characteristic and to a very homogeneous color impression of the radiation-emitting component.

On the LED chips 1 facing and / or facing away from the main surface 5 of the glass cover 3 may preferably be applied an anti-reflection layer (not shown). As a result, the luminance of the component improves further advantageous.

The carrier substrate 2 has a reflector layer 8 for the primary radiation emitted by the LED chips 1 during operation with the highest possible reflection coefficient, so that the primary radiation of the LED chips 1 is reflected in the direction of the glass cover 3. The highest possible reflection coefficient can be achieved, for example, by a suitable coating of the main surface of the carrier substrate 2 facing the LED chips 1.

The LED chips 1 are with particular advantage a thin-film LED chip.

In the embodiment of a radiation-emitting component illustrated in FIG. 2 in a plan view, a multiplicity of LED chips 1 are arranged on the carrier substrate. The glass cover 3 has a separate cavity 6 for each LED chip. Thus, the carrier substrate and the glass cover 3 each completely enclose an inner space in which exactly one LED chip is arranged. It is the Glass cover formed as a coherent, one-piece cover.

According to the embodiment of a production method according to the invention shown in FIG. 3, a carrier substrate 2 is provided which preferably contains silicon.

A main surface of the carrier substrate 2, which is provided as a mounting surface for LED chips 1, is coated so that the carrier substrate 2 has a reflector layer 8 for the primary radiation emitted by the LED chips 1 in operation with the highest possible reflection coefficient. On the carrier substrate 2 connecting points are applied, which are required for electrical contacting of the provided LED chips 1 (not shown). Subsequently, on the carrier substrate 2, as shown in Figure 3A, a plurality of LED chips 1 are applied, which on a

Based on nitride compound semiconductors. Subsequently, the LED chips 1 are electrically contacted with connection points of the carrier substrate 2 (not shown).

Subsequently, as shown in FIG. 3B, an adhesive 9 is applied in places to the carrier substrate 2. The adhesive 9 is, for example, an epoxy resin.

Subsequently, a glass cover 3 is produced, the extent of which is large enough to completely cover the carrier substrate 2 in a plan view of the carrier substrate 2. The glass cover 3 is formed by deep drawing, so that a plurality of cavities 6 is formed, wherein in each case a cavity for receiving an LED chip 1 is provided. Thus be just as many cavities 6 are formed, as LED chips 1 are arranged on the carrier substrate 2.

Subsequently, the glass cover 3 is applied to the support substrate 2, so that the glass cover 3 and the support substrate 2 are arranged flush with each other in plan view of the support substrate 2 (see Fig. 3C). The glass cover 3 in the present case consists of borosilicate glass and has cavities 6 which are suitable for accommodating one LED chip 1 each. The glass cover 3 is arranged at a distance from the LED chips 1, so that a gap 7 is formed, which is free of solid and liquid matter. In the present case, the intermediate space 7 contains air.

LED chips 1 show the highest luminance and brightness in air. The luminance increases compared to potted LED chips advantageous by about 15 percent. Furthermore, the glass cover 3 serves to protect the LED chips 1 from damage, for example due to shocks.

The glass cover 3 is arranged on the carrier substrate 2 such that the LED chips 1 each come to lie in a cavity 6. In the present case, the extent of the carrier substrate 2 and the glass cover 3 in the main extension plane of the carrier substrate 2 is the same size, and the carrier substrate 2 and the glass cover 3 are arranged flush with each other, so that they are congruent in plan view of the carrier substrate 2. The arranged between the cavities 6 areas of the carrier substrate 2 facing side of the glass cover 3 are at least partially wetted by the adhesive 9. Subsequently, the adhesive 9 is cured, so that a mechanically stable connection between the glass cover 3 and the carrier substrate 2 is formed. The LED chips 1 are enclosed in the cavity 6 in such a way that water and other corrosive substances can not possibly penetrate from the outer space into the cavity 6.

The curing of the adhesive 9 is preferably carried out by irradiation with focused laser radiation. The irradiation of the adhesive 9 takes place through the carrier substrate 2 and / or through the glass cover 3. The irradiation of the adhesive 9 takes place as uniformly as possible at all points. Thus, a homogeneous curing of the adhesive 9 is achieved.

In addition, on the surface facing the LED chips 1 and / or the surface of the glass cover 3 facing away from the LED chips, one or more conversion layers may be applied before the glass cover 3 is applied to the carrier substrate 2 (not shown). Alternatively, it is possible to melt a conversion substance in the glass cover. Further, an anti-reflection layer may be applied to one or more major surfaces of the glass cover 3 (not shown).

Subsequently, the LED chips are separated by means of cuts through the glass cover 3, the adhesive 9 and the carrier substrate 2 to form individual radiation-emitting components (see FIG. 3D). Only in this method step in the present case is the carrier substrate 2, that is to say the carrier substrate for the majority of the LED chips 1, patterned into individual carrier substrates and the one-piece glass cover 3 into individual glass covers 3. Alternatively, the glass cover 3 can be separated before application to the equipped with a plurality of LED chips 1 carrier substrate 2 (not shown). Subsequently, the radiation characteristics of the at least one applied conversion layer and / or the at least one introduced conversion substance of the individual glass covers 3 and the emission characteristics of the individual LED chips 1 mounted on the carrier substrate 2 can be measured separately. This makes it possible to selectively combine the individual glass covers 3 with the LED chips 1 mounted on the carrier substrate 2 in a sorting process and to mount them via the LED chips 1, whereby a desired color locus of the radiation-emitting component can be set. This allows a largely reproducible component characteristic.

The invention is not limited by the description based on the embodiments of these. Rather, the invention encompasses any novel feature as well as any combination of features, including in particular any combination of features in the claims, even if this feature or combination itself is not explicitly stated in the claims or exemplary embodiments.

Claims

claims

1. Radiation-emitting component having a carrier substrate (2), at least one LED chip (1) applied to the carrier substrate (2) and a radiation-transmissive glass cover (3) applied to the carrier substrate (2) and containing at least one cavity (6), which is suitable for receiving the at least one LED chip (1), wherein the glass cover (3) is arranged at a distance from the LED chip (1), so that a gap (7) between the at least one LED chip (1 ) and the glass cover (3), which is free of solid and liquid matter.

2. Radiation-emitting device according to claim 1, wherein the intermediate space (7) contains air.

3. Radiation-emitting component according to one of the preceding claims, wherein at least one conversion layer (4) on at least one main surface of the glass cover (3) is applied, which has at least one conversion substance, at least part of a of the LED chip (1) emitted primary radiation converted into a secondary radiation, wherein at least a part of the secondary radiation and a part of the unconverted primary radiation are superposed to a mixed radiation.

4. Radiation-emitting component according to one of the preceding claims, wherein at least one conversion substance in the glass cover (3) is distributed, wherein the Conversion substance converts at least a portion of one of the LED chip (1) emitted primary radiation into a secondary radiation, wherein at least a portion of the secondary radiation and a portion of the unconverted primary radiation superimposed to a mixed radiation.

5. Radiation-emitting component according to one of the preceding claims, wherein the glass cover (3) and the carrier substrate (2) in plan view of the carrier substrate (2) are arranged flush with each other.

6. Radiation-emitting component according to one of the preceding claims, wherein the glass cover (3) contains a borosilicate glass and the carrier substrate (2) silicon.

7. Radiation-emitting component according to one of the preceding claims, wherein the carrier substrate (2) contains ceramic, silicon or FR4.

8. Radiation-emitting component according to one of the preceding claims, wherein a plurality of LED chips (1) on the carrier substrate (2) is applied.

A radiation-emitting device according to claim 8, wherein the glass cover (3) has a plurality of cavities

(6), and each cavity (6) for receiving in each case an LED chip (1) is formed.

10. A method for producing a radiation-emitting component, comprising the steps of: a) providing a carrier substrate (2); b) applying at least one LED chip (1) to the carrier substrate (2); c) electrical contacting of the at least one LED chip (1) with connection points of the carrier substrate (2); d) producing a glass cover (3) and forming the glass cover (3) by deep drawing, so that the glass cover (3) has at least one cavity (6) for receiving the at least one LED chip (1); e) applying the glass cover (3) on the carrier substrate

(2) by means of a solder or adhesive layer (9).

11. The method according to claim 10, wherein on the at least one LED chip (1) facing surface and / or of the at least one LED chip (1) facing away from the surface of the glass cover (3) at least one conversion layer (4) is applied ,

12. The method according to any one of claims 10 or 11, wherein in the manufacture of the glass cover at least one conversion substance (4) is introduced into the glass cover (3).

13. The method according to any one of the preceding claims 10 to 12, wherein a plurality of LED chips (1) on the carrier substrate (2) is applied and a coherently produced glass cover (3) over the plurality of LED chips (1) is applied , and the glass cover (3) has a plurality of cavities (6) wherein each cavity is designed to receive one LED chip each.

14. The method according to claim 13, wherein the LED components are singulated by means of cuts which cut through the carrier substrate (2) and the coherent glass cover (3).

15. The method of claim 13 in combination with one of claims 11 or 12, wherein the glass cover (3) before application to the with a plurality of LED chips (1) equipped carrier substrate (2) is separated, then the radiation characteristics of at least an applied conversion layer (4) and / or the at least one introduced conversion substance (4) of the separated glass covers (3) and the emission characteristics of the individual, on the support substrate (2) mounted LED chips (1) are measured separately, and the individual glass covers (3) with the on the carrier substrate (2) mounted LED chips (1) selectively combined in a sorting and mounted on the LED chips (1).