DE10354936B4 - Radiation-emitting semiconductor component - Google Patents

Abstract

A radiation-emitting semiconductor component having a semiconductor body (1) which comprises a semiconductor layer sequence with an active zone (3) and a main surface (4), wherein in the active zone (3) radiation of a wavelength λ _{P is} generated,
characterized in that
On the main surface (4) a mirror layer (15) is arranged,
- The semiconductor body (1) is arranged downstream of a semiconductor conversion element (2),
The semiconductor conversion element (2) is excited by the radiation of wavelength λ _P generated in the active zone (3),
- The semiconductor conversion element (2) emits radiation of a wavelength λ _S1 , which is greater than the wavelength λ _P ,
The semiconductor layer sequence is arranged on a support (5) on the part of the main surface (4),
- The semiconductor conversion element (2) on the side of the carrier (5) is arranged, on which the semiconductor layer sequence is arranged,
The mirror layer (15) is arranged between the carrier (5) and the semiconductor layer sequence,
- The mirror layer (15) contains a metal, and ...

Description

The invention relates to a radiation-emitting semiconductor component having a semiconductor body which comprises a semiconductor layer sequence with an active zone and has a main surface, wherein radiation of a wavelength λ _{P is} generated in the active zone.

Such radiation-emitting semiconductor components are often used for producing mixed-color, in particular white light.

For this purpose, the radiation of the wavelength λ _P can, for example, excite a phosphor which is arranged in the envelope of the semiconductor component and reemit radiation of a greater wavelength. Such a device is in the document EP 1 347 517 A1 described. The two wavelengths are then superimposed to mixed-color light. However, the higher-energy radiation of the wavelength λ _P compared with the re-emitted radiation can increase the risk of premature aging or degradation of the cladding material, whereby the radiation decoupling is impaired and the lifetime of the component can be disadvantageously reduced. In particular, this applies when the phosphor is located relatively far from the active zone in the enclosure, and the higher energy radiation must pass through a majority of the enclosure to excite the phosphor.

Also in the pamphlets WO 00/76005 A1 and EP 1 132 977 A2 is described the generation of mixed-color light. Here, a layer of a semiconductor material is provided on the side facing away from the semiconductor layer sequence of the substrate, which can be excited by the wavelength λ _P and can reemit radiation of a larger wavelength. By superimposing these wavelengths mixed-colored light can arise.

However, the radiation of wavelength λ _P must first pass through the substrate before it can excite the semiconductor material. This can result in being partially absorbed by the substrate. The absorbed portion can thus no longer excite the semiconductor material. Furthermore, the relatively large distance of the semiconductor material layer from the active zone can lead to inefficient excitation of the semiconductor material, since the intensity of the radiation of wavelength λ _P decreases with increasing distance from the active zone.

From the publication WO 02/097902 A1 For example, an LED device with a pumping layer and an active layer is known, wherein the pump layer consisting of AlInGaN contains less indium.

The publication US 2002/0 139 984 A1 relates to a semiconductor light-emitting device having a light-generating active layer and a light-absorbing and emitting region.

The publication WO 99/50916 A1 describes a device having a primary light source and CdSe quantum dots embedded in a matrix and generating secondary radiation.

Object of the present invention is to provide a radiation-emitting semiconductor device of the type mentioned, which works as efficiently as possible, in particular with regard to the absorption of the radiation having the wavelength λ _P in the substrate. Furthermore, such a radiation-emitting semiconductor component should be as easy as possible to produce.

This object is achieved by a radiation-emitting semiconductor component having the features of patent claim 1 or 5.

In a first embodiment of a radiation-emitting semiconductor component according to the invention, the latter contains a semiconductor body which comprises a semiconductor layer sequence with an active zone and has a main surface, radiation of a wavelength λ _{P being} generated in the active zone. In this case, the semiconductor body is followed by a semiconductor conversion element, which is excited by the radiation generated in the active zone and emits radiation of a wavelength λ _S1 which is greater than the wavelength λ _P. Furthermore, the semiconductor layer sequence is arranged on the side of the main surface on a carrier or a growth substrate and the semiconductor conversion element on the side of the carrier with the semiconductor layer sequence.

In this embodiment, a mirror layer is arranged on the main surface, wherein the mirror layer is arranged between the carrier and the semiconductor layer sequence. The semiconductor component is designed as a thin-film component in which a growth substrate for the semiconductor layer sequence is removed and the semiconductor layer sequence is attached to the carrier. Furthermore, the semiconductor conversion element may be formed in several pieces.

In a further embodiment of a radiation-emitting semiconductor component according to the invention, the latter contains a semiconductor body which comprises a semiconductor layer sequence with an active zone and has a main area, radiation of a wavelength λ _{P being} generated in the active zone. The semiconductor body is followed by a semiconductor conversion element which is excited by the radiation generated in the active zone and radiation of a wavelength λ _S1 which is larger than the wavelength λ _P. Further, the semiconductor conversion element is formed in a plurality of pieces in the form of particles. The semiconductor conversion element contains at least one III-V semiconductor.

In a development of this embodiment, a mirror layer is arranged on the main surface and / or the semiconductor layer sequence is arranged on the side of the main surface on a carrier or a growth substrate.

The following statements relate to the features mentioned in the above-mentioned embodiments and in their developments and their advantages, as well as to further embodiments of the invention.

The semiconductor layer sequence preferably comprises at least one III-V semiconductor, more preferably In _x Ga _y Al _1-xy N, In _x Ga _y Al _1-xy P and / or In _x Ga _y Al _1-xy As, each with 0 ≤ x ≤ 1, 0 ≤ y ≤ 1 and x + y ≤ 1.

The carrier or the growth substrate on which the semiconductor layer sequence can be arranged preferably contains a material suitable for the respective semiconductor. For example, when In _x Ga _y Al _1-xy N is used, the support or growth substrate may include, for example, Si, SiC, sapphire, an SOI (silicone-insulator) structure, or other suitable materials or structures. These may possibly be doped to increase their conductivity - for example, SiC with N - or be provided with a conductor structure, if this is advantageous or necessary, for example, for the electrical contacting of the radiation-emitting semiconductor device.

The mirror layer is preferably arranged between the carrier or the growth substrate and the semiconductor layer sequence, for the wavelengths occurring reflective and / or electrically conductive. Such a mirror layer advantageously reduces the absorption of the radiation which occurs in a growth substrate or carrier which may be arranged underneath it and may also serve for the electrical contacting of the radiation-emitting semiconductor component. The mirror layer has, for example, a Bragg mirror and / or contains a metal, preferably Ag, Al, Au or Pt.

Furthermore, such a mirror layer can advantageously increase the proportion of the radiation of wavelength λ _P that can excite the semiconductor conversion element, since a larger portion of this radiation preferably strikes the semiconductor conversion element due to the reflection at the mirror layer.

Furthermore, such a mirror layer can also be arranged on the side of the semiconductor layer sequence opposite the main surface.

Preferably, the semiconductor layer sequence is grown epitaxially on the growth substrate and is possibly subsequently attached to the carrier. If, for example, a mirror layer is to be provided in the radiation-emitting semiconductor component which can not be grown epitaxially, it may be advantageous to use the still existing growth substrate of the semiconductor layer sequence using a suitable method - for example by mechanical stress, laser stripping or etching - To remove, and to secure the semiconductor layer sequence after applying the mirror layer on a support. The attachment to the carrier can be done before or after the detachment of the growth substrate. If, however, the growth substrate is removed from the support prior to attachment, the semiconductor layer sequence is advantageously mechanically stabilized, for example by a correspondingly large thickness of the semiconductor layer sequence, in order to avoid harmful effects. Such components, which are formed by detachment of the growth substrate and arrangement of the semiconductor layer sequence on a support, are also referred to as thin-film components.

The application of the mirror layer is carried out, for example, by vapor deposition or sputtering and the attachment by a, preferably metallic and / or electrically conductive, solder. In particular, this applies to components in which the mirror layer is arranged between the semiconductor layer sequence and the carrier.

The semiconductor conversion element downstream of the semiconductor body preferably contains a III-V semiconductor, particularly preferably In _x Ga _y Al _1-xy P, In _x Ga _y Al _1-xy N and / or In _x Ga _y Al _1-xy As, each with 0 ≤ x ≤ 1, 0 ≤ y ≤ 1 and x + y ≤ 1.

When a voltage is applied in the operating direction, radiation of the wavelength λ _{P is} generated in the active zone of the semiconductor layer sequence. The radiation of the wavelength λ _S1 is optically excited by the wavelength λ _P. The wavelength λ _P is absorbed by the semiconductor conversion element, and at least partially re-emitted as radiation of the wavelength λ _S1 . In this case, the re-emitted wavelength λ _{S1 is} greater than the exciting wavelength λ _P. The absorption and / or the reemission preferably take place in the III-V semiconductor. In this case, the re-emitted radiation power may depend on the absorbed radiation power and this in turn on the thickness of the absorbent material in the semiconductor conversion element.

In a preferred embodiment of the semiconductor conversion element, this comprises at least one layer which has been epitaxially grown on a substrate, for example. This layer preferably contains a III-V semiconductor, has an energy gap corresponding to the wavelength λ _S1 and / or emits radiation of this wavelength, which is excited by the wavelength λ _P. Since the radiation of the wavelength λ _P can be at least partially converted by this layer into radiation of the wavelength λ _S1 , this layer contained in the semiconductor conversion element is referred to below as a conversion layer. Furthermore, the conversion layer is preferably formed so that their energy gap and their layer thickness and thus the wavelength λ _S1 and the absorbed radiation power of wavelength λ _P are determined appropriately. The III-V semiconductor In _x Ga _y Al _1-xy P is particularly suitable for this because, depending on the composition, this material can emit radiation over a large spectral range, such as the green yellow or red region. In particular, this applies if the active zone of the radiation-emitting component contains In _x Ga _y Al _1-xy N and thus generates radiation of a wavelength which is smaller than the wavelengths of said spectral range.

The substrate of the conversion layer, which contains, for example, GaAs, is particularly preferably removed in the invention after the semiconductor conversion element has been arranged downstream of the semiconductor body. This removal can be done, for example, by mechanical stress, selective etching or a laser stripping process.

The substrate of the conversion layer can also be removed before the semiconductor conversion element is arranged downstream of the semiconductor body. However, the semiconductor conversion element is then advantageously mechanically stabilized, for example by a relatively large thickness, in order to avoid harmful effects.

Furthermore, the semiconductor conversion element, for example, before the removal of the substrate, arranged on a support layer and / or, for example, via a preferably radiation-transparent adhesive, be attached thereto. The carrier layer is advantageously permeable to the occurring radiation and / or electrically insulating or insulated with respect to the electrical contacting of the semiconductor layer sequence. Suitable materials for the carrier layer include, for example, electrically insulating glasses and electrically insulating crystals such as, for example, ZnO bulk crystals.

In a particularly preferred embodiment of the radiation-emitting semiconductor component, the radiations of the wavelengths λ _P and λ _{S1 are} at least partially superimposed to form mixed-color light. By mixed-colored light is meant light whose color coordinates indicate points within the boundary of the CIE color diagram. Among other things, the radiation can be superimposed to white light. Particularly preferred is λ _P in the blue and λ _S1 in the green to red spectral range.

It should be noted that under white light in the context of the invention in addition to pure white light with the color coordinates x = y = 1/3 in the CIE color diagram whitish light, for example, with a color cast, to understand. In case of doubt, the white light range can be used according to the definition in DIN 6163 Part 5 (Signaling device road) or the CIE standard.

In the context of the invention, the semiconductor conversion element may also be designed in such a way that the radiation of the wavelength λ _{P is} absorbed completely in it in such a way that the radiation-emitting semiconductor component emits light which gives a monochrome impression. Monochrome light, unlike mixed-color light, can also have color coordinates that indicate points on the edge of the CIE color chart.

The complete absorption can be achieved for example by a correspondingly thick semiconductor conversion element layer on the side of the semiconductor layer sequence opposite the main surface, a correspondingly high number of semiconductor conversion element particles on the semiconductor body and / or a correspondingly high density of suitable semiconductor conversion element particles in the enclosure. The mentioned embodiments of the semiconductor conversion element will be described in more detail below. The color of the monochromatic light is determined by the wavelength λ _S1 .

In a further preferred refinement of the semiconductor conversion element, this further comprises, in addition to the conversion layer, at least one protective layer, which advantageously has a III-V semiconductor such as, for example, In _x Ga _y Al _1-xy As, where 0 ≦ x ≦ 1, 0 ≦ y ≦ 1 and x + y ≤ 1. This protective layer advantageously reduces adverse external influences on the conversion layer - such as oxidation - and may also increase the efficiency of the semiconductor conversion element, for example, by reducing detrimental nonradiative surface recombination of electron-hole pairs in the conversion layer caused by the radiation of wavelength λ _P were raised. The protective layer particularly preferably contains GaAs or AlGaAs, is radiation-permeable and / or is arranged downstream of the conversion layer. With advantage borders one Such layer on at least one side directly to the conversion layer.

After the semiconductor conversion element has been manufactured, it can be formed in various ways and in the various forms. Exemplary embodiments are semiconductor conversion elements in layered and mehrstükkigen training, the latter in particular in the form of particles and multi-part layers. Under multi-part training is any training to understand in which the semiconductor conversion element is not connected in one piece, but is formed by several pieces. In particular, this also relates to multi-part formations, which arise by sawing or otherwise dicing the semiconductor conversion element. The semiconductor conversion element can also have mixtures of these embodiments.

Semiconductor conversion element particles in the above sense are all forms that can arise during comminution, especially when grinding, the semiconductor conversion element, such as regularly or irregularly shaped particles with curved or non-curved surfaces, such as platelet, cuboid or spherical shapes.

The particles are preferably designed so that the re-emitted radiation of wavelength λ _S1 with respect to each particle has an approximately equal radiant power, whereby the radiation of wavelength λ _S1 and thus the single- or mixed-color light, in particular with respect to the reemitierten radiation power, acting more homogeneous can.

The readjustment of the semiconductor conversion element with respect to the semiconductor body can be accomplished in various ways. In particular, the embodiments of the semiconductor conversion element in the above sense are possible. Examples are given by the at least partial arrangements on the semiconductor body, in particular its surface, or the carrier. Furthermore, in one of its embodiments, the semiconductor conversion element may at least partially be arranged downstream of the semiconductor body and / or the carrier, without being arranged thereon. A combination of the different arrangements of the semiconductor conversion element is possible.

In a preferred embodiment of the radiation-emitting semiconductor component, the semiconductor conversion element is arranged at least partially on the surface of the semiconductor body and is embodied, for example, in the form of a semiconductor conversion element layer, in several parts, or in particular as particles.

The semiconductor conversion element in a layered or multi-piece form may for example be fastened to a carrier layer of the abovementioned type and / or connected to the semiconductor body via a preferably radiation-transmissive adhesive. Particularly preferably, the carrier layer is arranged on the opposite side of the main surface of the semiconductor layer sequence.

If the semiconductor conversion element is arranged in the form of particles on the surface of the semiconductor body, the comminution is advantageously carried out without the carrier layer.

Such an arrangement has the advantage that the wavelength conversion can be carried out very effectively in the vicinity of the active zone, since the intensity of the radiation to be converted is higher in the vicinity of the active zone than further away from it. If the semiconductor body is at least partially surrounded by a cladding, such an arrangement of the semiconductor conversion element advantageously also reduces premature aging or degradation of the cladding material by the higher-energy radiation of the wavelength λ _P , since this is at least partially close to the semiconductor body in a lower energy of the wavelength λ _S1 is converted. Thus, the envelope of the higher-energy radiation is exposed only to a lesser extent.

In a further preferred refinement of the radiation-emitting semiconductor component according to the invention, the semiconductor body is at least partially surrounded by a cladding which contains, for example, a reaction resin such as an acrylic, silicone or epoxy resin or so-called mold compound.

Also in this embodiment, the semiconductor conversion element can be arranged in one of its embodiments at least partially on the surface of the semiconductor body or the carrier.

Particularly preferably, the semiconductor conversion element is arranged at least partially in the form of small particles in the enclosure. This can be advantageous in the production of such radiation-emitting semiconductor components, since the particles can be introduced into the cladding material before it is arranged around the semiconductor body. In this way, the semiconductor conversion element particles can be arranged simultaneously with the cladding around the semiconductor body.

Advantageously, the semiconductor conversion element particles in the cladding are arranged as close as possible to the semiconductor body or to the carrier, so that the wavelength conversion can take place as close as possible to the active zone. This has the name mentioned in the above embodiment Advantages and can be achieved by sedimentation of the particles prior to curing of the wrapping material.

In an advantageous development of the radiation-emitting semiconductor component, this contains at least one antireflection layer.

This antireflection layer is preferably such that a disadvantageous reflection of the occurring radiation, in particular at interfaces between layers and / or materials having a disadvantageously high refractive index difference, is reduced.

This can be achieved for example by a λ / 4 layer. This layer is preferably arranged between the semiconductor body and the semiconductor conversion element and advantageously reduces the reflection of the wavelength λ _P at an interface which lies between the semiconductor conversion element and the semiconductor body. More preferably, the antireflection layer has a refractive index intermediate between that of the adjacent layers. If the semiconductor layer sequence contains, for example, In _x Ga _y Al _1-xy N and the semiconductor conversion element In _x Ga _y Al _1-xy P, a suitable antireflection layer may contain, for example, SiN or SiO ₂ . Ideally, the refractive index of the antireflection layer is equal to the geometric mean of the refractive indices of the materials adjacent to the antireflective layers.

If the semiconductor conversion element is arranged in the form of particles in the cladding, it is also possible to provide corresponding antireflection layers which, for example, optimize the refractive index transition to the adjacent cladding material.

In an advantageous development of the radiation-emitting semiconductor component, the semiconductor conversion element of the abovementioned type can also contain a plurality of conversion layers with different energy gaps. These layers are preferably arranged one above the other on a common growth substrate or a carrier layer, for example by gluing or epitaxial growth. The carrier layer or the growth substrate are preferably radiation-transmissive. The different energy gaps correspond to different wavelengths. If the semiconductor conversion element has n conversion layers, wavelengths λ _Si (i = 1... N) can be excited in the individual conversion layers.

With respect to the design and the arrangement of the semiconductor conversion element as well as for producing mixed-color or monochromatic light, the above statements can be used. Carrier and / or protective layers can also be adjacent to the semiconductor conversion element or contained in it.

In a preferred embodiment, such a semiconductor conversion element, which comprises the conversion layers, as semiconductor conversion element layer or multi-part semiconductor conversion element on the semiconductor body arranged such that the energy gaps of the conversion layers decrease with increasing distance from the semiconductor body, and a conversion layer j radiation of wavelength λ _Sj emits from the radiation of at least one of the wavelengths λ _P or λ _S1 to λ _{S (j-1)} can be excited. In this case, the layer 1 of these conversion layers should be closest to the semiconductor body. Ideally, such a conversion layer can be excited by all radiations which are emitted from the direction of the semiconductor body and strike this layer.

In a further preferred refinement, such a semiconductor conversion element comprising the conversion layers is arranged as a semiconductor conversion element layer or multi-part semiconductor conversion element on the semiconductor body such that their energy gaps increase with increasing distance from the semiconductor body. Particularly preferably, the radiation of wavelength λ _{P is} the shortest wavelength radiation and can excite a plurality of conversion layers, which then emit radiation having longer wavelengths. Advantageously, the energy gaps of the conversion layers are therefore smaller than those of the wavelength λ _P. Furthermore, a conversion layer for the radiation emitted by conversion layers, which are arranged closer to the semiconductor body, permeable, since the energy gaps of the conversion layers increase with increasing distance from the semiconductor body.

If the radiations overlap in the sequence to mixed-colored, in particular white, light, a higher color rendering can be achieved by the mixed-color light because of the higher number of wavelengths involved.

Further features, advantages and expediencies of the invention will become apparent from the descriptions of the following embodiments in conjunction with the following figures.

Show it

1a and 1b a schematic sectional view of a first embodiment of a non-inventive radiation-emitting semiconductor device and a schematic sectional view of a second embodiment of a radiation-emitting semiconductor device according to the invention, and

2 a schematic sectional view of a third embodiment of a radiation-emitting semiconductor device according to the invention.

Similar and similar elements have the same reference numerals in the figures.

1 shows in the 1a and 1b a schematic sectional view of a first embodiment of a non-inventive semiconductor device and a second embodiment of a radiation-emitting semiconductor device according to the invention.

In both figures, a semiconductor body 1 of the radiation-emitting semiconductor component, a semiconductor conversion element 2 arranged downstream, which is designed as a semiconductor conversion element layer.

In the 1a is the semiconductor body 1 , which is a semiconductor layer sequence with an active zone 3 includes, on the part of its main surface 4 on a carrier 5 arranged. The semiconductor body 1 downstream is the semiconductor conversion element layer 2 connected to the semiconductor body 1 over a carrier layer 6 connected is. The electrical contacting of the radiation-emitting semiconductor component takes place through the electrodes 7 . 8th that with connections 9 . 10 are electrically connected to the external electrical contacting of the semiconductor device.

The carrier 5 is preferably identical to the growth substrate of the semiconductor layer sequence and contains, for example, SiC. Since the electrical contacting of the semiconductor device in this embodiment via the carrier 5 it follows that this is preferably doped with N to increase its conductivity.

However, the contacting of the semiconductor component can also be achieved by an arrangement of both electrodes on the side of the carrier 5 take place with the semiconductor layer sequence.

In the operation of the device is in the active zone 3 radiation 11a . 11b . 11c the wavelength λ _P generated. The semiconductor layer sequence with the active zone 3 , in which radiation is preferably generated in the blue spectral range, is formed for example in an LED chip, which is preferably based on In _x Ga _y Al _1-xy N.

The radiation of wavelength λ _P can in the direction of the semiconductor conversion element 2 or the carrier 5 be radiated, which is exemplified by the radiation components 11a and 11b respectively 11c is shown.

The amount 11b gets in the conversion layer 12 of the semiconductor conversion element 2 absorbed and can as radiation of wavelength λ _S1 with the corresponding radiation components 13a and 13b be re-emitted. The re-emitted wavelength is, for example, in the yellow or yellow-red spectral range.

The conversion layer 12 , which contains, for example, In _x Ga _y Al _1-xy P, is on both sides of a protective layer 14 , For example, of GaAs or AlGaAs surrounded, the adverse external influences on and / or adverse surface recombination in the conversion layer 12 can reduce and is designed to be transparent to radiation.

The conversion layer 12 is preferably epitaxially on a substrate - for example of GaAs - particularly preferably together with the protective layers 14 grown. Subsequently, the semiconductor conversion element 2 on the carrier layer 6 attached and the substrate removed.

Alternatively, the semiconductor conversion element 2 also attached via an adhesive on the semiconductor layer sequence and subsequently the substrate are detached. In this way, on the carrier layer 6 be waived.

The carrier layer arranged below the semiconductor conversion element 6 includes, for example, an electrically insulating ZnO bulk crystal, and is with both this, and the semiconductor conversion element 2 For example, connected via a radiation-transparent adhesive.

The radiation components 11c and 13b may be in the carrier 5 absorbed.

The radiation components of the reemitierten 13a and the transmitted 11a Radiation with the wavelengths λ _S1 or λ _P can be superimposed to mixed-colored, in particular white light.

Is the conversion layer 12 made so thick that the incident on this radiation of wavelength λ _{P is} completely absorbed, sends the semiconductor conversion element 2 Light from which one of the wavelength λ _S1 corresponding monochrome, for example, yellow, can make an impression.

Such a production of monochromatic light can have various advantages over the electro-optical generation of monochromatic light in an active zone with a corresponding energy gap.

On the one hand, this can bring with it advantages in the production, since only one active zone with a given energy gap and corresponding wavelength would have to be provided, which then has semiconductor conversion elements 2 with suitable conversion layers 12 would be re-emitted as monochromatic radiation longer wavelength.

On the other hand, the electro-optical radiation generation can be shifted into a structure that is more efficient compared to the material in which the desired radiation would be generated electro-optically. The efficiently generated radiation then becomes the semiconductor conversion element 2 converted into the desired radiation, wherein the semiconductor conversion element 2 , in particular its conversion layer 12 , advantageously has a high quantum efficiency. Thus, the electro-optical radiation generation often takes place very efficiently, for example in In _x Ga _y Al _1-xy N-based LED chips. The electro-optically generated radiation in this chip can via a conversion layer 12 , which contains, for example, In _x Ga _y Al _1-xy P - a material with high quantum efficiency - are converted into the desired single-color light.

The radiation-emitting semiconductor component can also comprise antireflection layers, which advantageously reduce reflection of the radiation occurring at interfaces. These are in the 1a not shown and can, for example, between the semiconductor conversion element 2 and the semiconductor body 1 be arranged.

The arrangement of the semiconductor conversion element layer on the carrier 5 opposite side of the semiconductor layer sequence leads to a wavelength conversion of the radiation generated in the active zone, which takes place very close to the active zone. The generation of lower-energy radiation 13a . 13b with the wavelength λ _S1 in the vicinity of the active region 3 prevents premature aging or degradation of a coating material arranged around the semiconductor body-for example, a reaction resin-as it may cause the more energy-rich radiation of the wavelength λ _P. Furthermore, a conversion is near the active zone 3 also more efficient, since the radiation of wavelength λ _P there has a higher intensity.

Furthermore, between the semiconductor conversion element 2 and the active zone 3 no absorbent structures, such as a growth substrate, are arranged.

This results in an overall efficient wavelength conversion close to the semiconductor body 1 takes place.

The electrical contacting of the device can, unlike shown by a recess in the semiconductor conversion element 2 and the carrier layer 6 respectively. This can be done, for example, by etching, or a multi-part design of the semiconductor conversion element 2 be achieved.

Furthermore, semiconductor conversion element particles or multiply formed semiconductor conversion elements or element layers can be arranged on the surface of the illustrated structure. This can be particularly advantageous if the semiconductor layer sequence is designed as an edge emitter and / or the radiation component 11c to be converted.

The semiconductor conversion element particles can also be arranged in an envelope of the illustrated structure.

That in the 1b illustrated radiation-emitting semiconductor device differs in structure from the in 1a shown essentially only by a mirror layer 15 ,

This mirror layer 15 is on the main surface 4 between the semiconductor body 2 and the carrier 5 arranged and electrically connected thereto. The mirror layer is reflective with respect to the radiation occurring and advantageously reduces the absorption of the radiation components 11c and 13b in the carrier, so that they also in the direction of the semiconductor conversion element 2 run and the share 11c in the conversion layer 12 can be absorbed or converted. This is in the 1b through the double arrows in the shares 11c and 13b for the reflection and the dashed line in 11c shown for the transmission.

The mirror layer 15 may be formed of a metal such as Al or Ag. This layer can be applied, for example, by sputtering or vapor deposition. In this case, the semiconductor body becomes 1 with the mirror layer 15 on the carrier 5 attached, after which the growth substrate can be removed.

Deviating from the mirror layer 15 For example, be formed by a Bragg mirror containing a plurality of layers of suitable semiconductor materials. Advantageously, the Bragg mirror and the semiconductor layer sequence can be produced on the same growth substrate, so that the carrier 5 may be given by this substrate.

The 2 shows a schematic sectional view of a third embodiment of a radiation-emitting semiconductor device according to the invention.

The semiconductor body 1 , the semiconductor layer sequence and the radiation generating active zone 3 is, on the part of its main surface 4 on a carrier 5 arranged. The semiconductor layer sequence is based on In _x Ga _y Al _1-xy N and the carrier 5 contains SiC that is doped with N to increase the conductivity. The electrical contacting of the semiconductor body 1 takes place via the electrodes 7 . 8th as well as the external connections 9 . 10 ,

The carrier 5 may be formed by the growth substrate of the semiconductor layer sequence.

This structure is of a cladding 16 surrounded, which contains a reaction resin and in which a semiconductor conversion element in the form of particles 17 is arranged. The particles 17 have a conversion layer 12 which contains, for example, In _x Ga _y Al _1-xy P, and a protective layer 14 For example, AlGaAs or GaAs.

The particles 17 are preferably prepared by grinding a semiconductor conversion element comprising said layers.

The of the active zone 3 generated radiation of wavelength λ _P 11 , represented by the radiation components 11a and 11b may be from the semiconductor conversion element particles 17 absorbed and as radiation 13 the longer wavelength λ _S1 of the conversion layer 12 be re-emitted.

The radiations 11a and 13 the wavelengths λ _P and λ _S1 can be superimposed to mixed-colored, in particular white light.

Is the density of the semiconductor conversion element particles 17 in the serving 16 big enough, the radiation-emitting semiconductor component emits light which gives a monochrome impression and whose color is determined by the wavelength λ _S1 .

The semiconductor conversion element particles are preferred 17 already present in the wrapping material before the semiconductor body is embedded therein. This has the advantage that the semiconductor conversion element can be provided together with the enclosure. Furthermore, the particles should be as close as possible to the semiconductor body 1 be arranged so that the wavelength conversion is done as efficiently as possible and premature aging or degradation of the wrapping material is avoided. This can be done, for example, by sedimentation of the particles 17 in the wrapping material before it hardens.

In addition, semiconductor conversion element layers or multiply formed semiconductor conversion elements or element layers on the surface of the semiconductor body can also be used 1 or the carrier 5 be arranged.

Furthermore, a mirror layer can also be used 15 as in 1b be provided, which is an absorption of the radiations in the carrier 5 prevents.

Claims (23)

Radiation-emitting semiconductor component with a semiconductor body ( 1 ), which has a semiconductor layer sequence with an active zone ( 3 ) and a main surface ( 4 ), wherein in the active zone ( 3 ) Radiation of a wavelength λ _P , characterized in that - on the main surface ( 4 ) a mirror layer ( 15 ), - the semiconductor body ( 1 ) a semiconductor conversion element ( 2 ), - the semiconductor conversion element ( 2 ) of the in the active zone ( 3 ) generated radiation of wavelength λ _{P is} excited, - the semiconductor conversion element ( 2 ) Emits radiation of a wavelength λ _S1 , which is greater than the wavelength λ _P , - the semiconductor layer sequence on the part of the main surface ( 4 ) on a support ( 5 ), - the semiconductor conversion element ( 2 ) on the side of the carrier ( 5 ) is arranged, on which the semiconductor layer sequence is arranged, - the mirror layer ( 15 ) between the carrier ( 5 ) and the semiconductor layer sequence is arranged, - the mirror layer ( 15 ) comprises a metal, and - the semiconductor component is designed as a thin-film component, in which a growth substrate for the semiconductor layer sequence is removed and the semiconductor layer sequence on the carrier ( 5 ) is attached. A radiation-emitting semiconductor component according to claim 1, characterized in that the semiconductor conversion element ( 2 ) is formed in several pieces. A radiation-emitting semiconductor component according to claim 2, characterized in that the semiconductor conversion element ( 2 ) at least partially the shape of small particles ( 17 ) having. A radiation-emitting semiconductor component according to one of the preceding claims, characterized in that the semiconductor conversion element ( 2 ) contains at least one III-V semiconductor, preferably In _x Ga _y Al _1-xy P, In _x Ga _y Al _1-xy N and / or In _x Ga _y Al _1-xy As, each with 0 ≤ x ≤ 1 , 0 ≤ y ≤ 1 and x + y ≤ 1. Radiation-emitting semiconductor component with a semiconductor body ( 1 ), which has a semiconductor layer sequence with an active zone ( 3 ) and a main surface ( 4 ), wherein in the active zone ( 3 ) Radiation of a wavelength λ _{P is} generated, characterized in that - the semiconductor body ( 1 ) a semiconductor conversion element ( 2 ), - the semiconductor conversion element ( 2 ) of the in the active zone ( 3 ) generated radiation of wavelength λ _{P is} excited, - the semiconductor conversion element ( 2 ) Emits radiation of a wavelength λ _S1 , which is greater than the wavelength λ _P , - the semiconductor conversion element ( 2 ) in the form of particles ( 17 ) is formed and - the semiconductor conversion element ( 2 ) contains at least one III-V semiconductor. A radiation-emitting semiconductor component according to claim 5, characterized in that the semiconductor conversion element ( 2 ) In _x Ga _y Al _1-xy P, In _x GaAl _1-xy N and / or InGa _y Al _1-xy As, each with 0 ≤ x ≤ 1, 0 ≤ y ≤ 1 and x + y ≤ 1. A radiation-emitting semiconductor component according to claim 5 or 6, characterized in that the semiconductor layer sequence on the part of the main surface ( 4 ) on a support ( 5 ) or a growth substrate. A radiation-emitting semiconductor component according to one of claims 5 to 7, characterized in that on the main surface ( 4 ) a mirror layer ( 15 ) is arranged. A radiation-emitting semiconductor component according to claims 7 and 8, characterized in that the mirror layer ( 15 ) between the growth substrate or the support ( 5 ) and the semiconductor layer sequence is arranged. A radiation-emitting semiconductor component according to claim 8 or 9, characterized in that the mirror layer ( 15 ) contains a metal. A radiation-emitting semiconductor component according to one of the preceding claims, characterized in that the semiconductor conversion element ( 2 ) at least one protective layer ( 14 ). A radiation-emitting semiconductor component according to one of the preceding claims, characterized in that the semiconductor conversion element ( 2 ) one or more conversion layers ( 12 ) (i = 1 ... n), each emitting radiation of wavelength λ _Si (i = 1 ... n). A radiation-emitting semiconductor component according to claim 12, characterized in that the radiations of the wavelength λ _P and the wavelengths λ _{Si are} at least partially superimposed to mixed-colored light, in particular white light. A radiation-emitting semiconductor component according to one of the preceding claims, characterized in that the radiation of the wavelength λ _{P is} so completely from the semiconductor conversion element ( 2 ) is absorbed so that the radiation-emitting semiconductor component emits light which gives a monochrome impression. A radiation-emitting semiconductor component according to one of the preceding claims, characterized in that the semiconductor conversion element ( 2 ) at least partially on the semiconductor body ( 1 ) is arranged. A radiation-emitting semiconductor component according to one of the preceding claims, characterized in that the semiconductor body ( 1 ) at least partially from an envelope ( 16 ) is surrounded. A radiation-emitting semiconductor component according to claim 16 with reference to claim 3 or 5 or a claim dependent on claim 3 or 5, characterized in that the particles ( 17 ) at least partially in the envelope ( 16 ) are arranged. A radiation-emitting semiconductor component according to one of the preceding claims, characterized in that the semiconductor conversion element ( 2 ) at least partially has a layer structure. A radiation-emitting semiconductor component according to claim 18, characterized in that the layer structure is supported on a carrier layer ( 6 ) is arranged. A radiation-emitting semiconductor component according to claim 19 with reference back to claim 1 or a claim dependent on claim 1, characterized that the carrier layer ( 6 ) on the support ( 5 ) opposite side of the semiconductor layer sequence is arranged. A radiation-emitting semiconductor component according to claim 19 or 20, characterized in that the carrier layer ( 6 ) is permeable to the radiation occurring. A radiation-emitting semiconductor component according to one of the preceding claims, characterized in that the semiconductor layer sequence contains a III-V semiconductor, preferably In _x Ga _y Al _1-xy N, In _x Ga _y Al _1-xy P and / or In _x Ga _y Al _1-xy As, each with 0 ≤ x ≤ 1, 0 ≤ y ≤ 1 and x + y ≤ 1. A radiation-emitting semiconductor component according to one of the preceding claims, characterized in that the semiconductor component has at least one antireflection layer.

Images