Semiconductor light emitting devices including flexible film having therein an optical element

• US 7,355,284 B2
• Filed: 03/29/2004
• Issued: 04/08/2008
• Est. Priority Date: 03/29/2004
• Status: Active Grant

• Current Assignee: CREE Led Incorporated (Smart Global Holdings Incorporated)
• Original Assignee: CREE Incorporated (Wolfspeed, Inc.)
• Inventors: Negley, Gerald H.
• Primary Examiner(s): Pham; Long
• Application Number:
  US10/811,598
• Publication Number:
  US 20050212405A1
• Time in Patent Office: 1,471 Days
• Field of Search: 257/778, 257/432
• US Class Current: 257/778
• 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 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• 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 33/58 Optical field-shaping elements
• CPC Class Codes: H01L 33/62 Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls

Abstract

Semiconductor light emitting devices include a substrate having a face, a flexible film that includes therein an optical element, on the face, and a semiconductor light emitting element between the substrate and the flexible film and configured to emit light through the optical element. The face can include a cavity therein, and the semiconductor light emitting element may be in the cavity. The flexible film extends onto the face beyond the cavity, and the optical element overlies the cavity.

Claims

1. A semiconductor light emitting device comprising:

a substrate having a face that includes a first cavity and a second cavity therein;

a flexible film that includes therein a first optical element and a second optical element that is spaced apart from the first optical element, wherein the flexible film extends onto, and is attached to, the face beyond the first and second cavities, the optical element overlies the first cavity and the second optical element overlies the second cavity;

a first semiconductor light emitting element in the first cavity and configured to emit light through the optical element;

a second semiconductor light emitting element in the second cavity and configured to emit light through the second optical element; and

an optical coupling media in the first cavity between the first optical element and the first semiconductor light emitting element and in the second cavity between the second optical element and the second semiconductor light emitting element.

3. A device according to claim 1 wherein the first optical element comprises a lens.

4. A device according to claim 1 wherein the first optical element comprises a prism.

5. A device according to claim 4 wherein the first semiconductor light emitting element includes a wire that extends towards the flexible substrate and wherein the prism is configured to reduce shadowing by the wire, of the light that is emitted from the first semiconductor light emitting element.

6. A device according to claim 3 further comprising phosphor on the flexible film between the lens and the first semiconductor light emitting element.

7. A device according to claim 6 wherein the lens includes a concave inner surface adjacent the first semiconductor light emitting element and wherein the phosphor comprises a conformal phosphor layer on the concave inner surface.

8. A device according to claim 1 wherein at least a portion of the flexible film that overlies the first cavity is transparent to the light and wherein at least a portion of the flexible film that extends onto the face beyond the fit cavity is opaque to the light.

9. A device according to claim 1 wherein at least a portion of the flexible film that overlies the first cavity comprises a first material and wherein at least a portion of the flexible film that extends onto the face beyond the first cavity comprises a second material.

10. A device according to claim 1 wherein the first semiconductor light emitting element includes a wire that extends towards and contacts the flexible film in the first cavity and wherein the flexible film includes a transparent conductor in the fit cavity that electrically connects to the wire.

11. A device according to claim 1 wherein the first optical element comprises a lens that overlies the first cavity and protrudes away from the first cavity, the flexible film further comprising a protruding element between the lens and the first semiconductor light emitting element that protrudes towards the first cavity.

12. A device according to claim 11 further comprising a conformal phosphor layer on the protruding element.

13. A device according to claim 1 wherein the flexible film includes a first face adjacent the substrate and a second face remote from the substrate and wherein the first optical element comprises a third optical element on the first face and a fourth optical element on the second face, both of which are located such that the first light emitting element emits light through the third optical element and the fourth optical element.

14. A device according to claim 1 further comprising an attachment element that is configured to attach the flexible film and the substrate to one another.

15. A device according to claim 1 further comprising a first phosphor layer on the flexible film between the first optical element and the first semiconductor light emitting element and a second phosphor layer on the flexible film between the second optical element and the second semiconductor light emitting element.

16. A device according to claim 15 wherein the first and second phosphor layers comprise different phosphors.

20. A device according to claim 1 wherein the first semiconductor light emitting element comprises a light emitting diode.

21. A device according to claim 1 wherein the flexible film includes therein a third optical element that is spaced apart from the first and second optical elements, the face including a third cavity therein, the device further comprising a third semiconductor light emitting element in the third cavity and configured to emit light through the third optical element, the device further comprising an optical coupling media in the third cavity between the third optical element and the third semiconductor light emitting element.

22. A device according to claim 21 further comprising a first phosphor layer on the flexible film between the first optical element and the first semiconductor light emitting element, a second phosphor layer on the flexible film between the second optical element and the second semiconductor light emitting element and a third phosphor layer on the flexible film between the third optical element and the third semiconductor light emitting element.

23. A device according to claim 22 wherein the first phosphor layer and the first semiconductor light emitting element are configured to generate red light, the second phosphor layer and the second semiconductor light emitting element are configured to generate blue light and the third phosphor layer and the third semiconductor light emitting element are configured to generate green light.

24. A device according to claim 1 wherein the first optical element comprises phosphor.

25. A device according to claim 24 wherein the first optical element comprises a lens having phosphor dispersed therein.

26. A device according to claim 1 wherein the first optical element comprises an optical emission enhancing and/or converting element.

27. A device according to claim 1 wherein the first optical element comprises an optical scattering element.

28. A device according to claim 6 wherein the optical coupling media is between the phosphor and the first semiconductor light emitting element.

29. A device according to claim 11 wherein the optical coupling media is between the protruding element and the first semiconductor light emitting element.

30. A device according to claim 12 wherein the optical coupling media is between the conformal phosphor layer and the first semiconductor light emitting element.

2. A semiconductor light emitting device comprising:

a substrate having a face that includes a cavity therein;

a flexible film that includes therein an optical element wherein the flexible film extends onto, and is attached to, the face beyond the cavity and the optical element overlies the cavity;

first and second semiconductor light emitting elements in the cavity; and

an optical media in the cavity that extends between the first and second semiconductor light emitting elements and the optical element.

17. A device according to claim 2 wherein the optical element is a first optical element, the flexible film includes therein a second optical element that is spaced apart from the first optical element and wherein the first and second optical elements overlie the cavity.

18. A device according to claim 17 further comprising a first phosphor layer on the flexible film between the first optical element and the first semiconductor light emitting element and a second phosphor layer on the flexible film between the second optical element and the second semiconductor light emitting element.

19. A device according to claim 18 wherein the first and second phosphor layers comprise different phosphors.