Optoelectronic Component, Method for Producing an Optoelectronic Component and Lighting Device

Abstract

In an embodiment an optoelectronic component includes a radiation emitting semiconductor chip configured to emit primary electromagnetic radiation from a radiation emission surface, a conversion element configured to convert the primary electromagnetic radiation into electromagnetic secondary radiation, a first potting covering at least one side surface of the semiconductor chip, a second potting arranged on the first potting and an adhesion promoter with which the conversion element is fixed on the radiation emission surface of the semiconductor chip, wherein the adhesion promoter is arranged on a top surface of the first potting, wherein the first potting includes first filler particles, wherein the second potting includes second filler particles, and wherein a mass fraction of the first filler particles is greater than a mass fraction of the second filler particles per volume element.

Claims

1.-18. (canceled)

19. An optoelectronic component comprising: a radiation emitting semiconductor chip configured to emit primary electromagnetic radiation from a radiation emission surface; a conversion element configured to convert the primary electromagnetic radiation into electromagnetic secondary radiation; a first potting covering at least one side surface of the semiconductor chip; a second potting arranged on the first potting; and an adhesion promoter with which the conversion element is fixed on the radiation emission surface of the semiconductor chip, wherein the adhesion promoter is arranged on a top surface of the first potting, wherein the first potting comprises first filler particles, wherein the second potting comprises second filler particles, and wherein a mass fraction of the first filler particles is greater than a mass fraction of the second filler particles per volume element.

20. The optoelectronic component according to claim 19, wherein the second potting covers at least one side surface of the conversion element.

21. The optoelectronic component according to claim 19, wherein the first potting completely covers at least the side surface of the semiconductor chip.

22. The optoelectronic component according to claim 19, wherein the adhesion promoter covers the top surface of the first potting and the side surface of the conversion element in places, and wherein an outer surface of the adhesion promoter has a convex, concave or triangular shape in cross-section.

23. The optoelectronic component according to claim 19, wherein the adhesion promoter is a thin layer.

24. The optoelectronic component according to claim 19, wherein the first filler particles are diffusely reflective for the primary electromagnetic radiation and/or the secondary electromagnetic radiation.

25. The optoelectronic component according to claim 19, wherein the second filler particles are diffusely reflective for the primary electromagnetic radiation and/or the secondary electromagnetic radiation.

26. The optoelectronic component according to claim 19, wherein the first filler particles and/or the second filler particles comprise TiO.sub.2 particles.

27. The optoelectronic component according to claim 19, wherein the first potting has a higher reflectivity for the primary electromagnetic radiation and/or the secondary electromagnetic radiation than the second potting.

28. The optoelectronic component according to claim 19, wherein the conversion element comprises a ceramic material.

29. The optoelectronic component according to claim 19, wherein the adhesion promoter is an adhesive.

30. A lighting device comprising: at least one optoelectronic component according to claim 19.

31. The lighting device according to claim 30, wherein the lighting device is a spotlight.

32. A method for producing an optoelectronic component, the method comprising: providing a radiation emitting semiconductor chip for emitting primary electromagnetic radiation from a radiation emitting surface; applying a first potting so that the first potting covers at least one side surface of the semiconductor chip; applying a second potting on the first potting, providing a conversion element for converting the primary electromagnetic radiation into secondary electromagnetic radiation; applying a material of an adhesion promoter to the radiation emitting surface of the semiconductor chip; and applying the conversion element to the material of the adhesion promoter, wherein the material of the adhesion promoter is partially displaced by the conversion element and is arranged on a top surface of the first potting, wherein the first potting comprises first filler particles, wherein the second potting comprises second filler particles, and wherein a mass fraction of the first filler particles is greater than a mass fraction of the second filler particles per volume element.

33. The method according to claim 32, wherein the material of the adhesion promoter is applied in flowable form and subsequently cured to form the adhesion promoter.

34. The method according to claim 33, wherein the material of the adhesion promoter wets the top surface of the first potting in places.

35. The method according to claim 32, wherein the material of the adhesion promoter completely wets the top surface of the first potting.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0080] In the following, the optoelectronic component, the method for producing the electronic component and the lighting device are explained in more detail with reference to the Figures by means of exemplary embodiments.

[0081] FIG. 1 shows a schematic sectional view of an optoelectronic component according to an exemplary embodiment;

[0082] FIGS. 2 and 3 show schematic sectional views of production stages of the method for producing an optoelectronic component according to an exemplary embodiment; and

[0083] FIGS. 4 and 5 each show schematic a sectional view of an optoelectronic component according to an exemplary embodiment.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

[0084] Identical, similar or similar-acting elements are provided with the same reference signs in the Figures. The figure and size ratios of the elements shown in the Figures are not to be regarded as to scale. Rather, individual elements can be shown exaggeratedly large for better representability and/or for better comprehensibility.

[0085] The optoelectronic component 1 according to the exemplary embodiment of FIG. 1 comprises a radiation emitting semiconductor chip 2 which is surrounded by a first potting 8. The semiconductor chip 2 is configured to emit electromagnetic primary radiation P from a radiation emission surface 3 during operation. A top surface of the semiconductor chip 4 here comprises the radiation emission surface 3.

[0086] The semiconductor chip 2 is a surface emitter in which the majority of the emitted primary radiation P, for example at least 80% of a radiation power, is emitted via the radiation emitting surface 3.

[0087] The first potting 8 embeds the semiconductor chip and the top surface of the semiconductor chip 4 is free of the first potting 8. The first potting 8 is in direct contact with the side surface of the semiconductor chip 5. Furthermore, first reflective filler particles are introduced into the first potting 8, which are configured to reflect primary radiation and/or secondary radiation.

[0088] The first potting 8 and the radiation emitting semiconductor chip 2 are arranged on a carrier 13. The first potting 8 has a thickness equal to a thickness of the radiation emitting semiconductor chip 2. Thus, the first potting 8 terminates flush with the top surface of the semiconductor chip 4 and the radiation emitting surface 3. Further, the thickness of the first potting 8 decreases away from the semiconductor chip 2.

[0089] A conversion element is arranged on the radiation emitting semiconductor chip 2 to convert primary electromagnetic radiation into secondary electromagnetic radiation. The electromagnetic secondary radiation comprises longer wavelengths than the electromagnetic primary radiation.

[0090] The conversion element 6 is fixed to the radiation emitting surface 3 of the semiconductor chip 2 by means of an adhesion promoter 10. The adhesion promoter 10 is arranged between the conversion element 6 and the radiation emitting semiconductor chip 2. Further, the adhesion promoter 10 surrounds the conversion element 6 in a closed form.

[0091] Between the semiconductor chip 2 and the conversion element 6, the adhesion promoter 10 preferably forms a thin layer and provides a mechanically stable connection. In the present case, the thin layer between the conversion element 6 and the radiation emitting semiconductor chip 2 has a thickness of at most 5 micrometres.

[0092] The adhesion promoter 10 is further arranged on a top surface of the first potting 9 in a region around the conversion element 6 and on at least one side surface of the conversion element 7. The side surface of the conversion element 7 is preferably covered in the vertical direction only up to a height by the adhesion promoter 10. In this case, the adhesion promoter 10 is in direct contact with the top surface of the first potting 9 and the side surface of the conversion element 7.

[0093] An outer surface of the adhesion promoter 11 facing away from the conversion element 6 and the first potting 8 has a convex shape in cross-section perpendicular to the lateral direction.

[0094] Furthermore, a second potting 12 is arranged on the first potting 8. The second potting 12 covers at least one side surface of the conversion element 7. The second potting 12 embeds the conversion element 6 such that a top surface of the conversion element is here completely free of the second potting 12. Furthermore, second reflective filler particles are introduced into the first potting 12, which are configured to reflect primary radiation and/or secondary radiation.

[0095] A mass fraction of the first filler particles is different from a mass fraction of the second filler particles in the exemplary embodiment of FIG. 1. The mass fraction of the first filler particles is greater than the mass fraction of the second filler particles. For example, the mass fraction of the first filler particles is at least 25% by weight and at most 50% by weight and the mass fraction of the second filler particles is at least 0% by weight and at most 30% by weight.

[0096] Advantageously, the primary electromagnetic radiation P, which is coupled into the adhesion promoter 10 and does not directly enter the conversion element 6, is reflected at the outer surface of the adhesion promoter 11 by means of the second potting 12 and is directed towards the conversion element 6.

[0097] In connection with the exemplary embodiment of FIGS. 2 and 3, production stages in the production of an optoelectronic component 1 are illustrated.

[0098] As shown in FIG. 2, the conversion element 6 and the radiation emitting semiconductor chip 2 are provided separately. A material of the adhesion promoter 14 is already applied to the radiation incident surface 2 of the radiation emitting semiconductor chip 2 in the form of a droplet as shown in FIG. 2. The material of the adhesion promoter 14 is present in a flowable form when applied.

[0099] In a next process step, the conversion element 6 is applied to the adhesion promoter 10, as shown in FIG. 3. The conversion element 6 is dipped centrally into the material of the adhesion promoter 14 with a bottom surface first and is preferably pressed against the radiation emitting semiconductor chip 2 with a constant pressure.

[0100] The adhesion promoter 10 is thus partially displaced by the conversion element 6 and is deposited on the top surface of the first potting 9 in the region around the conversion element 10. In addition, the displaced adhesion promoter 10 is deposited on the side surface of the conversion element 7.

[0101] In this case, the top surface of the first potting element 9 is not treated by means of a plasma treatment after application. Thus, the top surface of the first potting 9 generally has a comparatively low wettability for the adhesion promoter 10. As a result, the liquid material of the adhesion promoter 14 is only displaced into the region around the conversion element 6 onto the top surface of the first potting 9 and onto the side surface of the conversion element 7.

[0102] After the conversion element 6 has been applied to the semiconductor chip 2, the material of the adhesion promoter 14 to the adhesion promoter 10 is cured, for example, by means of UV irradiation.

[0103] In contrast to the optoelectronic component 1 according to the exemplary embodiment of FIG. 4, the optoelectronic component 1 according to the exemplary embodiment of FIG. 1 does not have a second potting 12. Furthermore, the adhesion promoter 10 is formed as a thin layer 16. Since the top surface of the first potting is here wettable by the adhesion promoter, the top surface of the first potting 9 is in this case completely covered by the adhesion promoter 10 in the form of a thin layer 16.

[0104] The thin layer 16 has a thickness of at most 5 micrometres. Further, the thickness of the thin layer 16 tapers away from the conversion element 6.

[0105] A cross-section perpendicular to the lateral direction of the thin layer 16 is so small that light conduction of primary radiation and secondary radiation is advantageously suppressed.

[0106] In contrast to the optoelectronic component 1 according to the exemplary embodiment of FIG. 5, the optoelectronic component 1 according to the exemplary embodiment of FIG. 1 also has no second potting. Furthermore, the top surface of the semiconductor chip 4 has an electrical contact 17. The electrical contact 17 can be electrically contacted by means of a bonding wire 18. In this case, an edge portion of the top surface of the semiconductor chip 4 in the region of the electrical contact 17 on the top surface of the semiconductor chip 4 is not part of the radiation emitting surface 3.

[0107] Between the adhesion promoter 10 and the electrical contact 17, the first potting 8 is arranged. Thus, a direct light conduction of primary radiation and/or secondary radiation through the adhesion promoter 10 to the electrical contact 17 is advantageously suppressed. Primary radiation and/or secondary radiation are thus not absorbed by the electrical contact 17, but reflected by the first potting 8. In this way, an increased light extraction and efficiency can be achieved.

[0108] In other words, the first potting 8 covers the electrical contact 17. The first potting 8 thereby protrudes beyond the top surface of the semiconductor chip 4 in the vertical direction in the region of the electrical contact 4. Furthermore, the first potting 8 partially covers the bonding wire 18.

[0109] The invention is not limited to the exemplary embodiments by the description based thereon. Rather, the invention encompasses any new feature as well as any combination of features, which in particular includes any combination of features in the claims, even if this feature or combination itself is not explicitly specified in the claims or exemplary embodiments.