This patent application is a national phase filing under section 371 of PCT/EP2018/054821, filed Feb. 27, 2018, which claims the priority of German patent application 102017104108.7, filed Feb. 28, 2017, each of which is incorporated herein by reference in its entirety.

TECHNICAL FIELD

The present invention relates to an optoelectronic component having a laser diode and to a method for producing an optoelectronic component having a laser diode.

BACKGROUND

In the prior art, it is known to connect a laser diode to a waveguide in the form of an optical fiber in order to guide the light in the desired direction starting from the laser diode.

SUMMARY OF THE INVENTION

Embodiments provide an improved optoelectronic component having a laser diode and a radiation guiding. Further embodiments provide a simple method for producing an optoelectronic component having a laser diode and a radiation guiding.

An advantage of the disclosed component is that a simple and reliable guiding of radiation of the electromagnetic radiation of the laser diode may be achieved by simple means. For this purpose, a laser diode is provided on a carrier, wherein the laser diode comprises a radiation surface for the electromagnetic radiation on a side face. Hence, the laser diode is embodied to emit the electromagnetic radiation in a lateral direction of radiation. A radiation-guiding layer arrangement is provided in the direction of radiation in front of the laser diode. The layer arrangement is an optical waveguide. The layer arrangement comprises at least a first layer and a second layer. The first layer is arranged on the carrier. The second layer is arranged on the first layer. The second layer is formed from a material which is transparent for the electromagnetic radiation of the laser diode. The first layer comprises a smaller optical refractive index than the second layer. For example, the refractive indices of the first and second layer may differ by at least 1%, in particular by 5% or even by more than 5%. The layer arrangement of the first and second layer is embodied and arranged in such a way that the electromagnetic radiation of the laser diode is coupled into the second layer. The second and first layer are embodied in such a way that the electromagnetic radiation is in the second layer guided to a radiation surface of the second layer and leaves the second layer via the radiation surface. In addition, the second layer is formed from a forming material.

Forming materials may be ductile materials produced from a liquid or pasty material. For example, the second layer may consist of silicone, epoxy resin, plastics or another transparent and liquid or pasty material, In particular, the second layer may consist of a molding material. Forming the second layer from a molding material allows for simple deposition of the second layer on the first layer. For example, the second layer may be sprayed onto the first layer. In addition, depending on the chosen embodiment, the second layer may be formed by means of a molding process with regard to its structure. In particular, the radiation surface of the second layer may be produced in a simple manner and having a desired alignment, a desired size and/or a desired roughness by means of a molding process.

In a further embodiment, the first layer comprises a radiation surface abutting on an irradiation surface of the second layer. The electromagnetic radiation leaves the first layer via the radiation surface and passes over into the second layer. The first layer may in this embodiment be formed from a forming material, wherein the radiation surface of the first layer is produced by means of a molding process. In this manner, the alignment, the size and/or the roughness of the radiation surface of the first layer may be produced in a precise manner.

In another embodiment, the first layer directly abuts on the radiation surface of the laser diode with an irradiation surface. The first and the second layer are embodied in such a way that the electromagnetic radiation from the laser diode is coupled into the second layer via the first layer. For this purpose, the first layer comprises a radiation surface that abuts on an irradiation surface of the second layer.

Depending on the chosen embodiment, the irradiation surface of the first layer may be arranged at a distance from the laser diode. A further material may be provided between the laser diode and the irradiation surface of the first layer. In addition, a free space may be provided between the radiation surface of the laser diode and the irradiation surface of the first layer.

In another embodiment, the second layer abuts on the radiation surface of the laser diode with an irradiation surface. In addition, depending on the chosen embodiment, the irradiation layer of the second layer may be arranged at a distance from the radiation surface of the laser diode. In this context, a free space may be provided between the radiation surface of the laser diode and the irradiation surface of the second layer.

If the irradiation surface of the first layer directly abuts on the radiation surface of the laser diode, the electronic radiation may be efficiently coupled into the first layer.

If the second layer abuts on the radiation surface of the laser diode with the irradiation surface, an improved coupling of the electromagnetic radiation directly into the second layer may be achieved, as well.

In another embodiment, the radiation surface of the second layer has a larger distance to the carrier than the radiation surface of the laser diode. This is achieved by embodying the first and second layer in such a way that a boundary surface between the first and second layer comprises an increasing distance to the carrier in the direction of the position of the radiation surface of the second layer. Thereby, a radiation guiding of the electromagnetic radiation away from the carrier is achieved by simple means. In this manner, e.g., shadowing effects of the carrier for the electromagnetic radiation of the laser diode may be reduced or avoided.

In a further embodiment, the radiation surface of the first layer and the radiation surface of the second layer are produced by means of compression molding. Compression molding is particularly suitable for forming precise surfaces with regard to the shape as well as with regard to the surface quality, in particular with regard to roughness.

Depending on the chosen embodiment, the first layer and/or the second layer may extend over an upper side of the laser diode. For example, the entire laser diode may be covered by the layer arrangement of the first and second layer. In this manner, the formation of the optical waveguide as well as a protection of the laser diode may be achieved by forming the layer arrangement. Depending on the chosen embodiment, only the first layer or only the second layer may cover the laser diode.

In a further embodiment, the layer arrangement comprises a third layer which is arranged on the second layer. The third layer has a smaller optical refractive index than the second layer. Thereby, a total reflection of the electromagnetic radiation at the boundary surface may be achieved between the second layer and the third layer. Moreover, by forming the third layer the second layer is protected against environmental influences. The refractive index of the second layer may, e.g., be higher by about 1% or by about 5% or more than the refractive index of the third layer. Depending on the chosen embodiment, the third layer may cover the radiation surface of the second layer and comprise a radiation surface, as well. Depending on the chosen embodiment, the radiation surface of the third layer may be produced by means of a forming process. In this embodiment, the third layer is also formed from a forming material, in particular from a molding material.

Depending on the chosen embodiment, the first layer or the third layer may comprise a trench, wherein the second layer is arranged within the trench. In this manner, the radiation guiding may be further improved as due to the width and the shape of the trench it is possible to more precisely guide the radiation. Due to the shape of the trench, the electromagnetic radiation may be guided not only vertically with regard to the carrier, but also horizontally with regard to the carrier. Furthermore, due to the shape of the trench, coupling into the second layer as well as coupling out of the second layer may be carried out by means of defined surfaces. Forming the trench and filling the trench with the second layer thus allows for flexible radiation guiding.

In another embodiment, the second layer is formed as a bridge on the first layer and covered by the third layer. Due to this embodiment, a good radiation guiding may be achieved by simple means.

