EP2409368A2

EP2409368A2 - Optoelectronic semiconductor component

Info

Publication number: EP2409368A2
Application number: EP10700750A
Authority: EP
Inventors: Martin Müller; Uwe Strauss
Original assignee: Osram Opto Semiconductors GmbH
Current assignee: Ams Osram International GmbH
Priority date: 2009-03-19
Filing date: 2010-01-20
Publication date: 2012-01-25
Also published as: DE102009013909A1; US20120250715A1; WO2010105865A3; CN102356522A; WO2010105865A2

Abstract

At least one embodiment of the optoelectronic semiconductor component (1) comprises an epitactically grown semiconductor body (2) having at least one active layer (3). The semiconductor body (2) of the semiconductor component (1) furthermore comprises at least one barrier layer (4), wherein the barrier layer (4) directly adjoins the active layer (3). In a variation direction or a longitudinal direction (L), perpendicular to a growth direction (G) of the semiconductor body (2), a material composition and/or a layer thickness of the active layer (3) and/or the barrier layer (4) is varied. Due to the variation of the material composition and/or the layer thickness of the active layer (3) and/or the barrier layer (4), an emission wavelength (λ) of a radiation (R) generated in the active layer (3), likewise in the variation direction or in the longitudinal direction (L), is set.

Description

description

Optoelectronic semiconductor device

An optoelectronic semiconductor component is specified.

DE 100 32 246 A1 discloses a luminescence diode chip based on InGaN and a method for its production.

An object to be solved is to specify an optoelectronic semiconductor component which emits electromagnetic radiation at at least two mutually different emission wavelengths.

According to at least one embodiment of the optoelectronic semiconductor component, this comprises an epitaxially grown semiconductor body having at least one active layer. It is possible that the entire semiconductor body is exclusively epitaxially generated. By way of example, the semiconductor body comprises exactly one active layer. The semiconductor body may have, in addition to the at least one active layer, further layers such as cladding layers, waveguide layers, contact layers and / or current spreading layers. For example, the semiconductor body is based on one of the following material systems: GaN, GaP, InGaP, InGaAl, InGaAlP, GaAs or InGaAs.

The active layer preferably comprises a pn junction, a double heterostructure, a single quantum well or single quantum well, in short SQW, or, more preferably, a multiple quantum well structure or multi quantum well, MQW for short, for generating radiation. Particularly preferably, the active layer a single quantum well structure or single quantum well, short SQW. The term quantum well structure unfolds no significance with regard to the dimensionality of the quantization. It thus includes quantum wells, quantum wires and quantum dots and any combination of these structures.

During operation of the semiconductor device, an electromagnetic radiation is generated in the active layer. The radiation generated in the active layer is preferably in one

Wavelength range between 300 nm and 3000 nm inclusive, in particular between 360 nm and 1100 nm inclusive.

In accordance with at least one embodiment of the optoelectronic semiconductor component, the semiconductor body is attached to a carrier. The carrier can be a growth substrate on which the semiconductor body has grown. It is also possible for the semiconductor body to have grown on a growth substrate and subsequently to be transposed onto a support which is different from the growth substrate.

In accordance with at least one embodiment of the optoelectronic semiconductor component, the semiconductor body comprises at least one barrier layer. The barrier layer is in particular such a layer which is in direct or direct contact with the at least one active layer. The at least one active layer and the at least one barrier layer are in other words adjacent.

In accordance with at least one embodiment of the optoelectronic semiconductor component, the semiconductor body has a variation direction which, in the context of the Manufacturing tolerances, oriented perpendicular to a growth direction of the semiconductor body. In other words, the direction of variation may be any direction oriented perpendicular to the direction of growth.

In accordance with at least one embodiment of the optoelectronic semiconductor component, a material composition and / or a layer thickness of the active layer and / or the barrier layer is varied. In other words, the material composition and / or the layer thickness of the active layer and / or the barrier layer changes in particular along the direction of variation. The material composition and / or the layer thickness is specifically adjusted here.

In accordance with at least one embodiment of the optoelectronic semiconductor component, an emission wavelength of a radiation generated in the active layer is set along the direction of variation. The emission wavelength here depends in particular on the material composition and / or the layer thickness of the at least one active one

Layer and / or the at least one barrier layer. Thus, the emission wavelength over the material composition and / or the layer thickness of the active layer and / or the barrier layer is set along the direction of variation.

In at least one embodiment of the optoelectronic semiconductor component, the latter comprises an epitaxially grown semiconductor body having at least one active layer. Furthermore, the semiconductor body of the semiconductor device has at least one barrier layer, wherein the barrier layer directly adjoins the active layer. Along a variation direction, perpendicular to a growth direction of the semiconductor body, is a Material composition and / or a layer thickness of the active layer and / or the barrier layer varies. By varying the material composition and / or the layer thickness of the active layer and / or the barrier layer, an emission wavelength of a radiation generated in the active layer, also along the direction of variation, is set.

In such a semiconductor device, it is possible that within a single, monolithic semiconductor body at different locations of the active layer, a radiation having different emission wavelengths can be generated, wherein the emission wavelength on the properties of the active layer and / or the barrier layer, ie over the thickness thereof and

Material composition, can be adjusted specifically.

For example, it is possible that such an optoelectronic semiconductor device is used for pumping a laser medium. A laser medium has, depending on a wavelength of a pump radiation, different penetration depths with respect to the pump radiation into the laser medium. If different pump wavelengths are used, the laser medium can be pumped more homogeneously. For example, this more homogeneous pumping results in improved mode quality or efficiency of laser radiation generated via the laser medium.

To pump a laser medium with different wavelengths, several different can simultaneously

Semiconductor devices are used, wherein each or more of the semiconductor devices emit radiation at different emission wavelengths. The use However, a plurality of different semiconductor devices increases the adjustment effort for the semiconductor devices. Also, the semiconductor devices are easier to misalign and cause a deterioration about the mode quality of the laser radiation generated in the laser medium.

It is likewise possible to use semiconductor components for pumping in which a plurality of active layers follow one another in the direction of growth of the semiconductor body. Each of the active layers following one another in the direction of growth then emits, for example, at a different emission wavelength. However, such a component has a comparatively high electrical resistance, which is accompanied by comparatively high electrical losses in the semiconductor body. To generate relatively high radiation intensities, as required for pumping a laser medium, such components are therefore often only suitable.

A further possibility of realizing a component which generates different emission wavelengths is to form different active layers in a direction perpendicular to the direction of growth of the semiconductor body. These laterally juxtaposed active layers can in particular successively in different

Be grown process steps. Such sequential growth of juxtaposed active layers is expensive because additional, different epitaxial growth steps are required. This can reduce the yield in the production of such a semiconductor device or even lead to a reduced quality and thereby to a reduced life. In accordance with at least one embodiment of the optoelectronic semiconductor component, this has an emission direction. The emission direction is, under the

Manufacturing tolerances, preferably both transversely, in particular perpendicular, oriented to the growth direction as well as transversely, in particular perpendicular, to one of the directions of variation. Furthermore, the emission direction is preferably oriented transversely, in particular perpendicular, to the growth direction. In this case, the emission direction is in particular the direction along which a maximum radiation intensity is emitted or the direction which represents a beam axis of the emitted radiation generated. It is not excluded that an emission of the radiation takes place in two opposite directions.

In other words, the emission direction, the direction of growth and this direction of variation are in each case oriented in pairs orthogonal to one another within the framework of the manufacturing tolerances. In the following, this variation direction, which is oriented perpendicular to both the growth direction and the emission direction, is referred to as the longitudinal direction. The longitudinal direction is therefore a special variation direction.

In accordance with at least one embodiment of the optoelectronic semiconductor component, this is designed as an edge-emitting semiconductor laser. The radiation generated in the semiconductor device can thus be a coherent laser radiation. The emission direction is then oriented in particular parallel to a resonator axis of a laser resonator, ie preferably perpendicular to both the longitudinal direction and the direction of growth. For example, the emission direction is then perpendicular to resonator mirrors of the laser resonator arranged. It is not necessary that a length of the laser resonator is smaller than an extension of the semiconductor body along the longitudinal direction.

In accordance with at least one embodiment of the optoelectronic semiconductor component, this is designed as a surface-emitting semiconductor laser. The semiconductor laser then preferably has a vertical resonator, in particular the semiconductor laser is thus a so-called vertical cavity surface emitting laser, in short VCSEL. It is possible for the semiconductor body then to comprise resonator mirrors designed approximately as Bragg mirrors. One of the resonator mirrors can also be present as an external component.

If the semiconductor component is designed as a surface-emitting laser, then the resonator axis and therefore in particular also the emission direction is preferably aligned parallel to the growth direction. Furthermore, the semiconductor component then preferably has a transverse direction, which is aligned perpendicular to both the longitudinal direction and the direction of growth.

According to at least one embodiment of the optoelectronic semiconductor component, the material composition and / or the layer thickness of the active layer and / or the barrier layer, within the manufacturing tolerances, varies exclusively along the longitudinal direction or one of the directions of variation. If, for example, the semiconductor device is an edge-emitting semiconductor laser, then the material composition and the layer thickness along the resonator axis of the laser resonator, parallel to the emission direction, are constant within the manufacturing tolerances. In accordance with at least one embodiment of the optoelectronic semiconductor component, a geometric length of the resonator, in particular in a direction perpendicular to a radiation exit side of the semiconductor device and / or parallel to the emission direction and / or perpendicular to the growth direction, is over the entire semiconductor device and / or over an entire, radiation-generating Range of the semiconductor device, in particular in the context of manufacturing tolerances constant. In other words, a variation of the emitted wavelength is then not achieved by a targeted, local variation of the resonator length.

In accordance with at least one embodiment of the optoelectronic semiconductor component, the barrier layer is located between two active layers. In this case, the barrier layer preferably directly adjoins the two active layers. Furthermore, the material composition and / or the layer thickness of the barrier layer along the longitudinal direction or the direction of variation, in particular exclusively along the longitudinal direction, is preferably varied.

According to at least one embodiment of the optoelectronic

Semiconductor component, the emission wavelength changes along the longitudinal direction or along the variation direction at a radiation passage area of the semiconductor body by at least 5 nm. Preferably, the changes

Emission wavelength along the longitudinal direction or along the direction of variation by at least 7 nm, more preferably by at least 10 nm, in particular by at least 15 nm. According to at least one embodiment of the optoelectronic semiconductor component, a spectral width of the radiation generated in the at least one active layer is at least 5 nm, preferably at least 7 nm, particularly preferably at least 10 nm, in particular at least 15 nm. In other words, the semiconductor component then emits in an im Substantially continuous spectral range with one of said spectral widths. The spectral width here is in particular the full width at half the height of the maximum, in short FWHM. It is possible that the spectrum of the generated radiation has local minima or maxima within the FWHM width.

In accordance with at least one embodiment of the optoelectronic semiconductor component, the emission wavelength along the longitudinal direction or along the direction of variation changes monotonically within the framework of the manufacturing tolerances. For example, if the longitudinal direction defines an x-axis, for example in the case where the emission wavelength increases monotonically, then at a position X ₁ the wavelength is less than or equal to a wavelength at a position X ₂ , where X i is less than X ₂ . The opposite applies in the case where the emission wavelength falls monotonously.

In accordance with at least one embodiment of the optoelectronic semiconductor component, the emission wavelength changes periodically along the longitudinal direction or along the direction of variation. The emission wavelength can show, for example, a sawtooth-like, rectangular or sinusoidal profile.

In accordance with at least one embodiment of the optoelectronic semiconductor component, the emission wavelength changes along the longitudinal direction or along the variation direction similar to a step function. In other words, the emission wavelength along the longitudinal direction or along the variation direction is approximately constant in sections and changes abruptly between individual sections. The step function is preferably monotonically decreasing or monotonically increasing along the longitudinal direction or along the direction of variation.

In accordance with at least one embodiment of the optoelectronic semiconductor component, the emission wavelength changes along the longitudinal direction or along the longitudinal direction

Variation direction, within the manufacturing tolerances, linear. Thus, the emission wavelength as a function of an x-position can be approximately described by a straight-line equation.

In accordance with at least one embodiment of the optoelectronic semiconductor component, the semiconductor body is designed as a one-piece laser bar. For example, the

Semiconductor body a cuboid, monolithic block.

In accordance with at least one embodiment of the optoelectronic semiconductor component, the at least one active layer is continuous along the longitudinal direction or along the direction of variation. The active layer is therefore not interrupted along the longitudinal direction or along the direction of variation by, for example, etched trenches.

In accordance with at least one embodiment of the optoelectronic semiconductor component, the latter has a plurality of electrical contact regions along the longitudinal direction or along the direction of variation. The contact areas are in this case set up for an electrical contacting of the semiconductor body. For example, along an upper side and / or a lower side of the

Semiconductor body, which limit the semiconductor body in a direction parallel to the growth direction, applied a plurality of single, point-like or strip-like metallizations. In the case of strip-like contact regions, the strips preferably extend along the emission direction.

In accordance with at least one embodiment of the optoelectronic semiconductor component, the contact regions are each assigned a specific emission wavelength. In other words, within a contact region, the emission wavelength is approximately constant. It is then possible for individual contact regions, in particular groups of contact regions having a specific emission wavelength, to be electrically controlled separately. In this way, the intensity of certain emission wavelengths can be adjusted in a targeted manner in relation to the intensity of other emission wavelengths.

According to at least one embodiment of the optoelectronic semiconductor component, this has between 10 and 100 contact regions, which are arranged along the longitudinal direction or along the direction of variation of the semiconductor body.

In accordance with at least one embodiment of the optoelectronic semiconductor component, a longitudinal extent of the semiconductor component along the longitudinal direction or along the direction of variation is between 3 mm and 20 mm inclusive, in particular between 5 mm and 15 mm inclusive. An expansion of the semiconductor body along the Emission direction, in particular a resonator length, is in the range between 0.5 mm and 10 mm inclusive, in particular between 1.5 mm and 4 mm inclusive.

In accordance with at least one embodiment of the optoelectronic semiconductor component, the latter is set up to generate an average radiation power of at least 30 W, in particular of at least 100 W. The semiconductor device may be operated in continuous wave mode, English continuous wave or short cw, or in a pulsed mode.

In accordance with at least one embodiment of the optoelectronic semiconductor component, the layer thickness of the active layer and / or the barrier layer varies along the longitudinal direction or along the direction of variation between 0.3 nm and 3.0 nm, in particular between 0.4 nm and 1.5 nm.

In accordance with at least one embodiment of the optoelectronic semiconductor component, the active layer has indium.

For example, the emission wavelength is then adjustable, in particular via an indium content.

According to at least one embodiment of the optoelectronic semiconductor device in which the active layer comprises indium, the indium content of the active layer varies along the longitudinal direction or along the direction of variation between 0.5 percentage points and 10 percentage points, in particular between 3 percentage points and 7 percentage points. The indium content refers to the proportion of, for example, gallium lattice sites, which instead of gallium by indium are taken, such as in the case of an AlGaAs based semiconductor body.

In accordance with at least one embodiment of the optoelectronic semiconductor component, the indium content is the active one

Between 1% and 30%, in particular between 3% and 27%. For example, it is also possible that the indium content is between 18% and 27% inclusive.

According to at least one embodiment of the optoelectronic semiconductor component, this comprises at least two, preferably at least three active layers which follow one another in the growth direction. In at least one, preferably in all active layers, the material composition and / or the layer thickness of the active layers themselves or of the at least one barrier layer is varied along one of the variation directions, in particular exclusively along the longitudinal direction. Particularly preferably, adjacent active layers along the growth direction, in a direction parallel to the growth direction, have different emission wavelengths.

In accordance with at least one embodiment of the optoelectronic semiconductor component, this is an edge-emitting laser and the semiconductor body is based on the AlGaAs material system. An indium content of the at least one active layer is varied along the longitudinal direction by at least 0.8 percentage points. The emission wavelength also changes along the longitudinal direction by at least 7 nm. In addition, the change of the emission wavelength along the longitudinal direction can be described by a linear function. There is also provided an apparatus for pumping a laser medium. For example, the device may comprise at least one optoelectronic semiconductor device, as described in connection with at least one of the preceding embodiments.

According to at least one embodiment of the device, the latter comprises at least one laser medium, the laser medium being optically pumped by the semiconductor component. The laser medium is preferably a solid-state laser medium. By way of example, the laser medium is a doped garnet or a doped glass.

According to at least one embodiment of the device, the latter comprises at least two, in particular at least three, optoelectronic semiconductor components, as specified in conjunction with one of the embodiments described above.

In addition to the use for pumping laser media, optoelectronic semiconductor components described here can also be used in display devices or in illumination devices for projection purposes. An application in headlights or light emitters or in the general lighting is possible, as well as in material processing.

In the following, an optoelectronic semiconductor component described here as well as a device described here for pumping a laser medium will be explained in more detail with reference to the drawing with reference to exemplary embodiments. The same reference numerals indicate the same elements in the individual figures. However, there are no scale relationships shown, but rather individual Elements for oversimplification may be exaggerated.

Show it:

1 shows a schematic three-dimensional representation of an optoelectronic device described here

Semiconductor device,

FIGS. 2 to 4 show schematic side views of further exemplary embodiments of optoelectronic semiconductor components described here,

FIGS. 5 and 6 are schematic illustrations of spectral characteristics of optoelectronic semiconductor devices described herein;

Figure 7 is a schematic side view of another

Embodiment of an optoelectronic semiconductor device described here,

FIG. 8 shows a schematic three-dimensional representation of an exemplary embodiment of a device described here for pumping a laser medium, and

FIGS. 9 and 10 are schematic representations of further exemplary embodiments of optoelectronic semiconductor components described here.

FIG. 1 illustrates a schematic three-dimensional representation of an exemplary embodiment of an optoelectronic semiconductor component 1. A semiconductor body 2 has an active layer 3. In the active layer 3 During operation of the semiconductor device 1, an electromagnetic radiation is generated.

Preferably, the semiconductor device 1 is designed as an edge-emitting laser or as a super-luminescent diode. The generation of the radiation in the active layer 3 is therefore based in particular on stimulated emission. For example, the radiation generated in the active layer 3 leaves the semiconductor body 2 at a radiation passage area 12 with a main emission direction perpendicular to the radiation passage area 12.

If the semiconductor component 1 is designed as a laser, then the radiation passage area 12 and one of the radiation passage area 12 form the opposite side of the semiconductor body 2, in each case at least in part, resonator end faces. A geometric resonator length and thus in particular an extension of the semiconductor body 2 along the emission direction E is, for example, between 1 mm and 5 mm inclusive.

Within the scope of manufacturing tolerances, the active layer 3 is flat. The semiconductor body 2 is produced by epitaxial growth. A growth direction G is within the manufacturing tolerances perpendicular to

Direction of emission E oriented and thus forms a normal to the active layer 3. An expansion of the semiconductor body 2 along the growth direction G is preferably less than 500 .mu.m, in particular less than 200 microns. Non-semiconductive materials such as heat sinks or metallic ones

In this case, contacts do not belong to the semiconductor body 2 and are not shown in FIG. Perpendicular to the direction of growth G and perpendicular to the emission direction E, a longitudinal direction L of the semiconductor body 2 is oriented. An extension of the semiconductor body 2 along the longitudinal direction L is for example between 5 mm and 15 mm. Along the

Longitudinal direction L is a material composition and / or a layer thickness of the active layer or adjacent to the active layer barrier layers 4 varies. As a function of the position of the semiconductor body 2 along the longitudinal direction L, an emission wavelength λ of the radiation is set via this variation of the layer thickness and / or the material composition.

FIG. 2 shows a schematic side view of the radiation passage area 12 of the semiconductor component 1. The semiconductor body 2 is grown on, for example, a GaAs substrate forming a support 9. An electrical contact region 7a, for example on an n-conducting side of the semiconductor body 2, is formed by the carrier 9. On an upper side 13 of the carrier 9, an n-cladding layer 6a is grown.

On a side of the cladding layer 6a facing away from the carrier 9 there is an n-waveguide layer 5a. In the direction away from the carrier 9, the waveguide layer 5a is followed by the active layer 3, a p-type waveguide layer 5b, a p-type cladding layer 6b and an electrical contact region 7b. The contact region 7b may be formed by one or more metallizations. The epitaxially grown semiconductor body 2 thus form the cladding layers 6a, 6b, the waveguide layers 5a, 5b and the active layer 3. Optionally, the semiconductor body 2 may also have at least one epitaxially grown, not shown in FIG Include contact layer, which is located between the cladding layer 6b and the contact layer 7b.

The two waveguide layers 5 a, 5 b are in direct contact with the active layer 3

Waveguide layers 5a, 5b thus simultaneously the barrier layers 4.

The thicknesses of the waveguide layers 5a, 5b, the cladding layers 6a, 6b and the active layer 3 are constant over the entire longitudinal direction L within the manufacturing tolerances. A thickness of the cladding layers 6a, 6b is in each case approximately 1 μm. The waveguide layers 5a, 5b have a thickness, in the direction of the growth direction G, of approximately 500 nm each. A thickness D of the active layer 3 is approximately 8 nm.

Along the longitudinal direction L, a material composition of the active layer 3 is varied. For example, if the semiconductor body is based on the AlGaAs material system, in particular an indium content of the active layer 3 is varied by approximately 3 percentage points to 7 percentage points, so that the emission wavelength λ of the radiation along the longitudinal direction L is varied by approximately 30 nm. The absolute indium content of the active layer 3 is, for example, between 20% and 30% inclusive. Perpendicular to the radiation passage area 12, ie parallel to the emission direction E, the material composition as well as the thickness D of the active layer 3 is constant within the manufacturing tolerances.

In the embodiment of the semiconductor device 1 according to FIG. 3, the thickness of the active layer 3 is varied. The thickness in Direction parallel to the growth direction G corresponds to a value Dl on one side of the semiconductor body 2. The thickness grows along the longitudinal direction L as part of the

Manufacturing tolerances linearly to a value D2. Perpendicular to the radiation passage area 12, the thickness remains constant, within the framework of the manufacturing tolerances. For example, the thickness D1 is approximately 7.0 nm and the thickness D2 is approximately 8.5 nm. The wavelength increases, for example, from approximately 800 nm to approximately 810 nm in the course of thickness from D1 to D2.

In addition to the variation of the thickness D 1, D 2 of the active layer 3, it is optionally also possible to additionally vary the material composition of the active layer 3 in the longitudinal direction L. Alternatively or additionally, a material composition of the barrier layers 4, here formed by the waveguide layers 5a, 5b, may also be varied.

In the exemplary embodiment of the semiconductor component 1 according to FIG. 4, the semiconductor body 2 has two active layers 3a, 3b. Between these active layers 3a, 3b there is a barrier layer 4 different from the waveguide layers 5a, 5b. Along the longitudinal direction L, the thickness of the barrier layer 4 decreases from a value B1 to a value B2. For example, the value Bl is about 10 nm and the value B2 is about 8 nm.

Via the barrier layer 4, the two active layers 3a, 3b are coupled to one another. This coupling has an influence, for example, on one

Energy level structure of quantum wells of the active layers 3a, 3b. For example, the emission wavelength is in The radiation generated with the active layers 3a, 3b is increasingly shifted with decreasing thickness of the barrier layer 4 into the longer wavelength spectral range.

In particular, those explained in Figures 2 to 4

Options for setting the emission wavelength λ of the radiation can also be combined with one another in a single component. For example, the

Material composition of the at least one active layer 3 and the thickness of the barrier layer 4 combined and adjusted.

In FIG. 5, curves of the emission wavelength λ plotted against a position along the longitudinal direction L are illustrated. According to Figure 5A is a

Wavelength constant and thus not varied along the longitudinal direction L. A corresponding semiconductor component emits radiation only in a comparatively narrow spectral range.

In the figures 5B to 5E are courses of the

Emission wavelength λ for semiconductor devices 1 shown approximately according to Figures 1 to 4. According to FIG. 5B, the emission wavelength λ decreases linearly along the longitudinal direction L.

A sinusoidal profile of the emission wavelength λ along the longitudinal direction L is shown in FIG. 5C. According to FIG. 5D, the emission wavelength λ first increases linearly with increasing position with respect to the longitudinal direction L and subsequently decreases linearly again. In the course of the emission wavelength λ according to FIG. 5E, there is a step-function-like course. That is, within certain ranges, the emission wavelength λ is approximately constant and changes abruptly between individual plateaus.

In addition to the courses shown in FIGS. 5B to 5E, other courses are also possible. For example, the emission wavelength λ may change in a sawtooth manner along the longitudinal direction L or may be a combination of the courses shown.

In FIG. 6, an intensity I of the radiation emitted by the semiconductor component 1 is plotted against the emission wavelength λ. According to FIG. 6A, the radiation has a comparatively small spectral width w. The spectrum shown corresponds approximately to that of a semiconductor element according to FIG. 5A, in which the wavelength along the longitudinal direction is not set or varied.

The intensity distribution according to FIG. 6B originates, for example, from a semiconductor component 1 according to FIG. 5B described here, in which the emission wavelength λ is varied linearly along the longitudinal direction L. The intensity distribution has a comparatively large spectral width w. The spectrum shows a broad maximum in which the intensity I is approximately constant over a relatively large spectral range. The spectral width w according to FIG. 6b is, for example, at least three times as large as the spectral width w according to FIG. 6A Semiconductor element in which the emission wavelength λ is not adjusted and varied.

According to FIG. 6C, the intensity I with respect to the emission wavelength λ has two maxima separated from one another by a pronounced minimum. Such a spectrum may result from a semiconductor device 1, for example according to FIG. 6E, in which the emission wavelength λ along the longitudinal direction L shows a step-function-like course. Unlike shown in Figure 6C, the spectrum may also have significantly more than two maxima. Also in accordance with FIG. 6C, the spectral width w is significantly greater than approximately according to FIG. 6A.

In the semiconductor device 1 according to FIG. 7, a multiplicity of electrical contact regions 7b are applied to a side of the semiconductor body 2 facing away from the carrier 9. By way of example, the contact regions 7b are designed in a strip-like manner, with the contact regions 7b extending mainly in a direction perpendicular to the radiation passage area 12, parallel to the emission direction E. In this case, the semiconductor body 2 preferably has a low electrical transverse conductivity in a direction parallel to the longitudinal direction L, so that energization of the active layer 3 takes place approximately only parallel to the growth direction G, starting from the contact regions 7b.

The electrical contact regions 7b cover, for example, a surface portion of the side facing away from the carrier 9 of the semiconductor body 2 between 10% and 95%, in particular between 50% and 80% inclusive. A width of the contact regions 7b is along the longitudinal direction preferably between 10 μm and 300 μm inclusive, in particular between 50 μm and 200 μm inclusive.

Alternatively or additionally, it is also possible for the electrical contact regions 7a on the carrier 9 to likewise be patterned like a strip, analogously to the contact regions 7b.

In particular, it is possible for the semiconductor device 1 to have between 5 and 100 such contact regions 7b. For example, each of the contact regions 7b is a wavelength generated in the active layer 3 .lambda..sub.i to λ _n can be assigned. Likewise, the contact regions 7b can be electrically controlled individually. In this way, a targeted adjustment of the intensity I of the radiation as a function of the emission wavelength λ can be realized.

At least one heat sink 11 may optionally be attached to a side of the contact regions 7b and / or the support 9 facing away from the support 9. By means of the at least one heat sink 11, heat arising during operation of the semiconductor component 1 can be dissipated efficiently in particular from the semiconductor body 2. The support 9 and / or the heat sink 11 may be a metal, sapphire, GaN, SiC, GaSb or InP. It is also possible that the carrier 9 and the heat sink 11 constitute composite bodies.

FIG. 8 illustrates an exemplary embodiment of a device for pumping a laser medium 8. Two optoelectronic semiconductor components 1, for example according to FIGS. 1 to 7, serve for optical pumping of the laser medium 8. The radiation R, which forms the radiation passage areas 12 leaves in the region of the active layer 3, is led directly to the laser medium 8. The emission wavelength λ is varied along the active layers 3 parallel to the longitudinal direction L. In the laser medium 8 takes place over the volume of the laser medium 8 relatively uniform absorption of the pump radiation R.

Optionally, non-drawn optical elements such as light guides, lenses or mirrors may be mounted between the optoelectronic semiconductor devices 1 and the laser medium 8, for example to realize a uniform mixing of the radiation R generated by the semiconductor devices 1 and to ensure a spectrally uniform illumination of the laser medium 8 ,

FIG. 9A shows a three-dimensional schematic representation of a further exemplary embodiment, according to which the semiconductor component 1 is designed as a surface-emitting laser, or VCSEL for short. The emission direction E is oriented parallel to the growth direction G. The

Radiation passage area 12 is also oriented perpendicular to the growth direction G. A transverse direction Q is oriented both perpendicular to the growth direction G and perpendicular to the longitudinal direction L.

The semiconductor body 2 has three contiguous regions in which radiation with emission wavelengths λi, λ ₂ , λ3 different from one another is emitted. The material composition and / or the layer thickness of the at least one active layer of the semiconductor body 2 is preferably only varied along the longitudinal direction L, along the transverse direction Q is the Material composition and / or the layer thickness that is preferably constant. For example, the

Material composition and / or the layer thickness along the longitudinal direction L similar to a step function, analogous to Figure 5E, varies.

In the exemplary embodiment of the semiconductor component 1 according to the side view in FIG. 9B, the semiconductor bodies 2a, 2b, 2c are grown on the common carrier 9. In operation, a radiation with a different emission wavelength λi, λ ₂ , λ3 is generated in each of the semiconductor bodies 2a, 2b, 2c.

According to the side view in FIG. 10, the semiconductor device 1 designed as an edge-emitting laser comprises three active layers 3 a, 3 b, 3 c that follow one another along the direction of growth G. The

Radiation passage area 12 is aligned parallel to the plane of the drawing. Between adjacent active layers 3a, 3b, 3c are respectively the cladding layers 6, the waveguide layers 5 and a tunnel diode 14. In each of the active layers 3a, 3b, 3c, the layer thickness and / or the material composition is varied along the longitudinal direction L. The variation takes place, for example, similar to a step function, analogous to FIG. 5E.

_A <λ _2, _a <λ _3, _a .lambda..sub.i: for the emission wavelengths .lambda..sub.i, _a, λ _2, _a, ^ _3, _a of the carrier 9 next active layer 3 applies to the example. The emission wavelengths generated along the growth direction G .lambda..sub.i, _a, .lambda..sub.i, _b, .lambda..sub.i, _c of the active layers 3a, 3b, 3c are also different from each other are preferred.

For example, λi, _a > λi, _b > λi, _c . The same can also apply to the emission wavelengths λ ₂ , _a , λ ₂ , _b , λ ₂ , _c , λ ₃ , _a , λ ₃ , b / λ ₃ , _c .

In other words, it is possible for the radiation passage area to have, in plan view, subareas arranged in matrix form. In each of the sections, a different emission wavelength can be emitted. The emission wavelength is thus varied, for example, both along the longitudinal direction L and, via the stack-like arrangement of the active layers 3a, 3b, 3c, along the growth direction G.

The invention described here is not limited by the description based on the embodiments. 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 patent claims or exemplary embodiments.

This patent application claims the priority of German Patent Application 10 2009 013 909.5, the disclosure of which is hereby incorporated by reference.

Claims

claims

1. Optoelectronic semiconductor device (1) with

an epitaxially grown semiconductor body (2) having at least one active layer (3),

at least one barrier layer (4) directly adjoining the active layer (3), along a variation direction (L), perpendicular to a growth direction (G) of the semiconductor body (2), a material composition and / or a layer thickness (B, D) of the active layer (3) and / or the barrier layer (4) is varied, and along the variation direction (L) by the variation of the material composition and / or the layer thickness (B, D) of the active layer (3) and / or the barrier layer (4) an emission wavelength (λ) of a radiation generated in the active layer (3) is set.

2. An optoelectronic semiconductor device (1) according to claim 1, which is an edge-emitting semiconductor laser or a surface-emitting semiconductor laser.

3. An optoelectronic semiconductor device (1) according to any one of the preceding claims, wherein the material composition and / or the

Layer thickness (B, D) of the active layer (3) and / or the barrier layer (4) only in a longitudinal direction (L), perpendicular to an emission direction (E) and perpendicular to the growth direction (G) is varied, the emission direction ( E) is oriented transversely to the growth direction (G).

4. The optoelectronic semiconductor device (1) according to any one of the preceding claims, wherein the emission wavelength (λ) along the variation direction or along the longitudinal direction (L) at a radiation passage area (12) changes by at least 5 nm.

5. An optoelectronic semiconductor device (1) according to one of the preceding claims, wherein the emission wavelength (λ) varies monotonically along the direction of variation or along the longitudinal direction (L).

6. The optoelectronic semiconductor component (1) according to one of the preceding claims, wherein the emission wavelength (λ) changes along the direction of variation or along the longitudinal direction (L) periodically and / or in the form of a step function.

7. Optoelectronic semiconductor component (1) according to one of the preceding claims, wherein the semiconductor body (2) is designed as a one-piece laser bar.

8. The optoelectronic semiconductor device (1) according to any one of the preceding claims, wherein the at least one active layer (3) along the direction of variation or along the longitudinal direction (L) is contiguous.

9. Optoelectronic semiconductor component (1) according to one of the preceding claims, along the variation direction or along the longitudinal direction (L) has a plurality of electrical contact regions (7), which are adapted for electrical contacting of the semiconductor body (2), and in which the contact regions (7) each assigned a certain emission wavelength (λ) is.

10. The optoelectronic semiconductor component (1) according to one of the preceding claims, wherein an expansion of the semiconductor body (2) along the direction of variation or along the

Lenght (L) between 3 mm and 30 mm and along the emission direction (E) between 1 mm and 10 mm.

11. The optoelectronic semiconductor device (1) according to any one of the preceding claims, which is adapted to produce an average radiation power of at least 30 W.

12. The optoelectronic semiconductor component (1) according to one of the preceding claims, wherein the layer thickness (B, D) of the active layer (3) and / or the barrier layer (4) along the direction of variation or along the longitudinal direction (L) between 0, 3 nm and 3.0 nm is varied.

13. An optoelectronic semiconductor device (1) according to any one of the preceding claims, wherein the active layer (3) In, and in which an In content of the active layer (3) along the variation direction or along the longitudinal direction (L) between 0.5 percentage points and 10 percentage points.

14. The optoelectronic semiconductor component according to claim 1, wherein the semiconductor body is based on the AlGaAs material system.

in which the In content of the at least one active layer (3) is varied by at least 0.5 percentage points along the longitudinal direction (L), - in which the emission wavelength (λ) changes by at least 5 nm along the longitudinal direction (L) , and

- In which the emission wavelength (λ) along the longitudinal direction (L) changes linearly.

15. An apparatus for pumping a laser medium (8) with - at least one optoelectronic semiconductor device (1) according to one of the preceding claims, and

- At least one laser medium (8), wherein the laser medium (8) of the semiconductor device (1) is optically pumped.