Lighting module and method for the production thereof

• US 7,560,741 B2
• Filed: 01/15/2004
• Issued: 07/14/2009
• Est. Priority Date: 02/28/2003
• Status: Active Grant

• Current Assignee: OSRAM OLED GMBH (Ams-Osram AG)
• Original Assignee: Osram Opto Semiconductors GmbH (Ams-Osram AG)
• Inventors: Lugauer, Hans-Jurgen, Harle, Volker, Hahn, Berthold
• Primary Examiner(s): Richards; N Drew
• Assistant Examiner(s): Patton; Paul E
• Application Number:
  US10/547,217
• Publication Number:
  US 20060163601A1
• Time in Patent Office: 2,007 Days
• Field of Search: 257/79, 257/86, 257/87, 257/88, 257/89, 257/90, 257/91, 257/94, 257/95, 257/98, 257/99, 257/100, 257/101, 257/102, 257/103
• US Class Current: 257/98
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48465 the other connecting portion not on the bonding area being a wedge bond, i.e. ball-to-wedge, regular stitch
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/16195 Flat cap [not enclosing an internal cavity]
• CPC Class Codes: H01L 33/22 Roughened surfaces, e.g. at the interface between epitaxial layers
• CPC Class Codes: H01L 33/486 adapted for surface mounting
• CPC Class Codes: H01L 33/507 the elements being in intimate contact with parts other than the semiconductor body or integrated with parts other than the semiconductor body
• CPC Class Codes: H01L 33/54 having a particular shape
• CPC Class Codes: H01L 33/56 Materials, e.g. epoxy or silicone resin
• CPC Class Codes: H01L 33/60 Reflective elements

Abstract

An illumination module with at least one thin-film light emitting diode chip which is applied on a chip carrier having electrical connecting conductors and has a first and a second electrical connection side and also an fabricated semiconductor layer sequence. The semiconductor layer sequence has an n-conducting semiconductor layer, a p-conducting semiconductor layer and an electromagnetic radiation generating region arranged between these two semiconductor layers and is arranged on a carrier. Moreover, it has a reflective layer at a main area facing toward the carrier, which reflective layer reflects at least one part of the electromagnetic radiation generated in the semiconductor layer sequence back into the latter. The semiconductor layer sequence has at least one semiconductor layer with at least one micropatterned, rough area. The coupling-out area of the thin-film light emitting diode chip is essentially defined by a main area remote from the reflective layer and is free of housing material such as potting or encapsulating material.

Claims

1. A light emitting semiconductor component with at least one thin-film light emitting diode chip which is applied on a chip carrier having electrical connecting conductors and an epitaxial semiconductor layer sequence, wherein the semiconductor layer sequence is arranged on a carrier and comprises:

(a) an n-conducting semiconductor layer, a p-conducting semiconductor layer and an electromagnetic radiation generating region arranged between these two semiconductor layers;

(b) at least one semiconductor layer with at least one micropatterned, rough area;

(c) a coupling-out area essentially defined by a main area facing away from the carrier;

(d) a housing frame arranged on one of the chip carrier and a housing bottom which is different than the chip carrier, the housing bottom including a plurality of electrical connecting conductors to which the chip carrier is applied and electrically connected such that a housing cavity is defined in which the thin-film light emitting diode is arranged; and

(e) a radiation-transmissive covering plate arranged to essentially at least one of cover and close an opening of the housing cavity;

wherein a reflective layer is arranged at a main area of the semiconductor facing toward the carrier, which reflective layer reflects at least one part of the electromagnetic radiation generated in the semiconductor sequence layer back into the semiconductor sequence layer, and the coupling-out area adjoins at least one element of the group consisting of a region filled with gas, a region filled with a vacuum, and a luminescence conversion material wavelength-converting at least one part of an electromagnetic radiation emitted by the thin-film light emitting diode chip and adjoining the region filled with gas or the vacuum;

the epitaxial semiconductor layer sequence generates electromagnetic radiation at a wavelength in the UV range;

the thin-film light emitting diode chip has a thickness of less than 100 μ

m inclusive; and

wherein at least one part of the luminescence conversion material is applied to at least one of two main areas of the covering plate, the luminescence conversion material completely covering one of the main areas of the covering plate.

2. The light emitting semiconductor component as claimed in claim 1, wherein the semiconductor layer sequence contains at least one material from the system In_xAl_yGa_1-x-yN where 0≦

x≦

1, 0≦

y≦

1 and x+y≦

1.

3. The light emitting semiconductor conductor as claimed in claim 1, wherein the main area of the radiation-transmissive covering plate that faces an interior of the housing cavity is covered by the conversion material.

4. The light emitting semiconductor component as claimed in claim 1, wherein the carrier on which the semiconductor layer sequence is arranged is a carrier substrate.

5. The light emitting semiconductor component as claimed in claim 4, wherein the carrier substrate is a semiconductor carrier substrate.

6. The light emitting semiconductor component as claimed in claim 1, wherein the carrier on which the semiconductor layer sequence is arranged is the chip carrier.

7. The light emitting semiconductor component as claimed in claim 1, wherein the housing cavity is defined by a leadframe around which a housing basic body is formed, the bottom of the housing basic body with the part of the leadframe integrated therein forming the chip carrier or the housing bottom.

8. The light emitting semiconductor component as claimed in claim 7, wherein the housing basic body is essentially composed of plastic.

9. The light emitting semiconductor component as claimed in claim 1, wherein inner walls of the housing cavity are at least partly provided with a layer which is reflective for an electromagnetic radiation generated in the semiconductor component.

10. The light emitting semiconductor component as claimed in claim 9, wherein the reflective layer is electrically conductive and also electrically connected to the thin-film light emitting diode chip.

11. The light emitting semiconductor component as claimed in claim 9, wherein the layer is a metallic or oxidic layer.

12. The light emitting semiconductor component as claimed in claim 11, wherein the layer includes TiO₂, Ag, Al or Au.

13. The light emitting semiconductor component as claimed in claim 1, wherein inner walls of the housing cavity are at least partly provided with a diffusor material or with a layer which is diffusely reflective for an electromagnetic radiation generated in the semiconductor component.

14. The light emitting semiconductor component as claimed in claim 1, wherein the housing cavity is closed off in at least one of a gastight and watertight manner.

15. The light emitting semiconductor component as claimed in claim 1, wherein the radiation-transmissive covering plate is shaped at least such that said radiation-transmissive covering plate comprises an optical device for beam shaping of an electromagnetic radiation emitted by the semiconductor component.

16. The light emitting semiconductor component as claimed in claim 15, wherein the optical device comprises a focusing apparatus.

17. The light emitting semiconductor component as claimed in claim 1, wherein the radiation-transmissive covering plate essentially comprises at least one of glass, quartz glass, ceramic and glass ceramic.

18. The light emitting semiconductor component as claimed in claim 1, wherein the covering plate is provided with a diffusor material which is at least one of contained in the radiation-transmissive covering plate and applied on the covering plate.

19. The light emitting semiconductor component as claimed in claim 1, wherein at least one main area of the covering plate has a rough structure.

20. The light emitting semiconductor component as claimed in claim 19, wherein at least one main area of the covering plate that faces an interior of the housing cavity has a rough structure.

21. The light emitting semiconductor component as claimed in claim 19, wherein the rough structure of the at least one main area of the radiation-transmissive covering plate is irregular.

22. The light emitting semiconductor component as claimed in claim 19, wherein the rough structure of the at least one main area of the radiation-transmissive covering plate has a structure size which is an order of magnitude of a wavelength of an electromagnetic radiation emitted by the semiconductor component.

23. The light emitting semiconductor component as claimed in claim 21, wherein the rough structure of the at least one main area of the radiation-transmissive covering plate comprises a multiplicity of partial areas which are oblique with respect to a main plane of extent of the semiconductor layer sequence and form a multiplicity of different angles with the semiconductor layer sequence, and which are distributed statistically over an entirety of the at least one main area.

24. The light emitting semiconductor component as claimed in claim 23, wherein the multiplicity of partial areas are distributed statistically over the entirety of the at least one entire main area with regard to said multiplicity of different angles.

25. The light emitting semiconductor component as claimed in claim 1, wherein an additional luminescence conversion material is arranged downstream of the thin-film light emitting diode in an emission direction, the additional luminescence conversion material wavelength-converting at least one part of an electromagnetic radiation emitted by the thin-film light emitting diode.

26. The light emitting semiconductor component as claimed in claim 25, wherein the luminescence conversion material comprises at least two phosphors that differ with regard to at least one of conversion properties and particle size.

27. The light emitting semiconductor component as claimed in claim 14, wherein a luminescence conversion material is arranged downstream of the thin-film light emitting diode in the emission direction, the luminescence conversion material wavelength-converting at least one part of an electromagnetic radiation emitted by the thin-film light emitting diode;

and wherein at least one part of the luminescence conversion material is admixed with the radiation-transmissive covering plate.

28. The light emitting semiconductor component as claimed in claim 1, wherein the luminescence conversion material is applied in the form of a converter layer having a surface which comprises a rough structure.

29. The light emitting semiconductor component as claimed in claim 28, wherein the rough structure of the converter layer is irregular.

30. The light emitting semiconductor component as claimed in claim 28, wherein the converter layer comprises a multiplicity of crystallites, and the rough structure of the converter layer is essentially defined by the form of the crystallites.

31. The light emitting semiconductor component as claimed in claim 28, wherein the rough structure of the converter layer has a structure size which is of the an order of magnitude of the a wavelength of an electromagnetic radiation emitted by the semiconductor component.

32. The light emitting semiconductor component as claimed in claim 29, wherein the rough structure of the converter layer comprises a multiplicity of partial areas which are oblique with respect to a main plane of extent of the semiconductor layer sequence and form a multiplicity of different angles with the semiconductor layer sequence, and which are distributed statistically over an entirety of the converter layer.

33. The light emitting semiconductor component as claimed in claim 32, wherein the multiplicity of partial areas are distributed statistically over the entirety of the at least one main area with regard to said multiplicity of different angles.

34. The light emitting semiconductor component as claimed in claim 1, wherein the luminescence conversion material comprises at least two phosphors that differ with regard to conversion properties and particle size.

35. The light emitting semiconductor component as claimed in claim 1, wherein the luminescence conversion material has a surface comprising a rough structure.

36. The light emitting semiconductor component as claimed in claim 35, wherein the rough structure of the luminescence conversion material is irregular.

37. The light emitting semiconductor component as claimed in claim 36, wherein the rough structure of the luminescence conversion material comprises a multiplicity of partial areas which are oblique with respect to a main plane of extent of the semiconductor layer sequence and form a multiplicity of different angles with the semiconductor layer sequence, and which are distributed statistically over an entirety of the luminescence conversion material.

38. The light emitting semiconductor component as claimed in claim 35, wherein the luminescence conversion material comprises a multiplicity of crystallites, and the rough structure of the luminescence conversion material is essentially defined by the form of the crystallites.

39. The light emitting semiconductor component as claimed in claim 35, wherein the rough structure of the luminescence conversion material has a structure size of an order of magnitude of a wavelength of an electromagnetic radiation emitted by the semiconductor component.

40. The light emitting semiconductor component as claimed in claim 37, wherein the multiplicity of partial areas are distributed statistically over the entirety of the at least one main area with regard to said multiplicity of different angles.

45. The light emitting semiconductor component as claimed in claim 1, wherein the thin-film light emitting diode chip is contact-connected on two opposite main areas.

41. A light emitting semiconductor component with at least one thin-film light emitting diode chip which is applied on a chip carrier having electrical connecting conductors and an epitaxial semiconductor layer sequence, wherein the semiconductor layer sequence is arranged on a carrier and comprises;

(a) an n-conducting semiconductor layer, a p-conducting semiconductor layer and an electromagnetic radiation generating region arranged between these two semiconductor layers;

(b) at least one semiconductor layer with at least one micropatterned, rough area;

(c) a housing frame arranged on one of the chip carrier and a housing bottom which is different than the chip carrier, the housing bottom including a plurality of electrical connecting conductors to which the chip carrier is applied and electrically connected such that a housing cavity is defined in which the thin-film light emitting diode is arranged; and

(d) a radiation-transmissive covering plate arranged to essentially at least one of cover and close an opening of the housing cavity;

wherein a reflective layer is arranged at a main area of the semiconductor layer sequence facing toward the carrier, which reflective layer reflects at least one part of the electromagnetic radiation generated in the semiconductor layer sequence back into the semiconductor layer sequence;

an emission side of the thin-film light emitting diode chip facing away from the chip carrier is free of housing material;

the carrier on which the semiconductor layer sequence is arranged is a carrier substrate of the thin-film light emitting diode chip, said carrier substrate being arranged between the chip carrier and the reflective layer;

the epitaxial semiconductor layer sequence generates electromagnetic radiation at a wavelength in the UV range;

the thin-film light emitting diode chip has a thickness of less than 100 μ

m inclusive; and

wherein at least one part of the luminescence conversion material is applied to at least one of two main areas of the covering plate, the luminescence conversion material completely covering one of the main areas of the covering plate.

42. The light emitting semiconductor component as claimed in claim 41, wherein the carrier substrate is a semiconductor carrier substrate.

43. A light emitting semiconductor component with at least one thin-film light emitting diode chip which is applied on a chip carrier having electrical connecting conductors and an epitaxial semiconductor layer sequence, wherein the semiconductor layer sequence is arranged on a carrier and comprises:

(a) an n-conducting semiconductor layer, a p-conducting semiconductor layer and an electromagnetic radiation generating region arranged between these two semiconductor layers;

(b) at least one semiconductor layer with at least one micro-patterned, rough area;

(c) a housing frame arranged on one of the chip carrier and a housing bottom which is different than the chip carrier, the housing bottom including a plurality of electrical connecting conductors to which the chip carrier is applied and electrically connected such that a housing cavity is defined in which the thin-film light emitting diode is arranged; and

(d) a radiation-transmissive covering plate arranged to essentially at least one of cover and close an opening of the housing cavity;

wherein a reflective layer is arranged at a main area of the semiconductor layer sequence facing toward the carrier, which reflective layer reflects at least one part of the electromagnetic radiation generated in the semiconductor layer sequence back into the semiconductor layer sequence;

an emission side of the thin-film light emitting diode chip facing away from the chip carrier is free of housing material;

a growth substrate on which the epitaxial semiconductor layer sequence is grown is removed at least for the most part; and

the thin-film light emitting diode chip is free of a carrier substrate at the emission side of the thin-film light emitting diode chip facing away from the chip carrier;

the epitaxial semiconductor layer sequence generates electromagnetic radiation at a wavelength in the UV range;

the thin-film light emitting diode chip has a thickness of less than 100 μ

m inclusive; and

wherein at least one part of the luminescence conversion material is applied to at least one of two main areas of the covering plate, the luminescence conversion material completely covering one of the main areas of the covering plate.

44. A light emitting semiconductor component with at least one thin-film light emitting diode chip which is applied on a chip carrier having electrical connecting conductors and also an epitaxial semiconductor layer sequence, wherein the semiconductor layer sequence is arranged on a carrier and comprises:

(a) an n-conducting semiconductor layer, a p-conducting semiconductor layer and an electromagnetic radiation generating region arranged between these two semiconductor layers; and

(b) at least one semiconductor layer with at least one micropatterned, rough area;

wherein a reflective layer is arranged at a main area of the semiconductor layer sequence facing toward the carrier, which reflective layer reflects at least one part of the electromagnetic radiation generated in the semiconductor layer sequence back into the latter;

an emission side of the thin-film light emitting diode chip facing away from the chip carrier is free of housing material;

the semiconductor component having a housing frame and electrical connectors, said semiconductor being arranged on one of the chip carrier and a housing bottom which is different than the chip carrier, the chip carrier being applied to and electrically connected to the electrical connecting conductors of the semiconductor component such that a housing cavity is defined in which the thin-film light emitting diode chip is arranged;

the semiconductor component comprises a radiation-transmissive covering plate fitted such that the covering plate essentially at least one of covers and closes an opening of the housing cavity; and

a luminescence conversion material that wavelength-converts at least one part of the electromagnetic radiation emitted by the thin-film light emitting diode chip is admixed with the covering plate;

the epitaxial semiconductor layer sequence generates electromagnetic radiation at a wavelength in the UV range; and

wherein the thin-film light emitting diode chip has a thickness of less than 100 μ

m inclusive.

46. The light emitting semiconductor component as claimed in claim 44, wherein the thin-film light emitting diode chip is contact-connected on two opposite main areas.