Semiconductor light emitting device

• US 8,334,548 B2
• Filed: 03/25/2008
• Issued: 12/18/2012
• Est. Priority Date: 03/30/2007
• Status: Active Grant

• Current Assignee: ROHM Co., Ltd.
• Original Assignee: ROHM Co., Ltd.
• Inventors: Kobayakawa, Masahiko
• Primary Examiner(s): HO, HOANG QUAN TRAN
• Application Number:
  US12/593,836
• Publication Number:
  US 20100044737A1
• Time in Patent Office: 1,729 Days
• Field of Search: None
• US Class Current: 257/99
• 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 25/167 comprising optoelectronic devices, e.g. LED, photodiodes
• 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 33/486 adapted for surface mounting
• 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
• CPC Class Codes: H01L 33/647 the elements conducting electric current to or from the semiconductor body

Abstract

A semiconductor light emitting device (A) includes a lead frame (1) having a constant thickness, a semiconductor light emitting element (2) supported by the lead frame (1), a case (4) covering part of the lead frame (1) and a light transmitting member (5) covering the semiconductor light emitting element (2). The lead frame (1) includes a die bonding pad (11a) and an elevated portion (11b). The die bonding pad (11a) includes an obverse surface on which the semiconductor light emitting element (2) is mounted, and a reverse surface exposed from the case (4). The elevated portion (11b) is shifted in position from the die bonding pad (11a) in the direction normal to the obverse surface of the die bonding pad (11a).

Claims

1. A semiconductor light emitting device comprising:

a lead frame having a constant thickness;

a semiconductor light emitting element supported by the lead frame;

a resin case covering part of the lead frame; and

a light transmitting member covering the semiconductor light emitting element;

wherein the lead frame includes a first frame element and a second frame element, the first frame element including a die bonding pad and a first terminal, the second frame element including an elevated portion and a second terminal,

wherein the first terminal and the second terminal project from a same side surface of the resin case,

wherein the die bonding pad includes an obverse surface on which the semiconductor light emitting element is mounted and a reverse surface exposed from the resin case,

wherein the first frame element includes an additional elevated portion that is offset with respect to the obverse surface of the die bonding pad in a direction normal to the obverse surface,

wherein the lead frame includes an easily deformable portion embedded in the resin case, the easily deformable portion connecting the bonding pad and the additional elevated portion, and

wherein the first frame element includes a third terminal and a fourth terminal, and the first terminal, the third terminal and the fourth terminal are flush with the die bonding pad.

3. The semiconductor light emitting device according to claim 1, wherein the elevated portion of the second frame element and the additional elevated portion are offset in a same direction.

4. The semiconductor light emitting device according to claim 1, wherein the elevated portion of the second frame element and the additional elevated portion are offset by a same amount.

6. The semiconductor light emitting device according to claim 1, further comprising a first resin covering the semiconductor light emitting element and containing a fluorescent material.

7. The semiconductor light emitting device according to claim 6, further comprising a second resin covering the first resin, wherein the second resin is transparent.

8. The semiconductor light emitting device according to claim 7, further comprising a third resin covering the second resin, wherein the third resin contains a light scattering material dispersed therein.

9. The semiconductor light emitting device according to claim 8, wherein the third resin is a lens form.

10. The semiconductor light emitting device according to claim 1, wherein the additional elevated portion includes a part exposed from the resin case on a same side of the obverse surface of the die bonding pad.

11. The semiconductor light emitting device according to claim 1, wherein the die bonding pad is rectangular.

12. The semiconductor light emitting device according to claim 11, wherein the easily deformable portion is adjacent to a vertex of the rectangular die bonding pad.

15. The semiconductor light emitting device according to claim 1, wherein the resin case is formed with a reflector enclosing the semiconductor light emitting element.

16. The semiconductor light emitting device according to claim 1, wherein the die bonding pad and the additional elevated portion are flat and parallel to each other.

17. The semiconductor light emitting device according to claim 1, wherein each of the first terminal, the third terminal and the fourth terminal includes a reverse surface flush with the reverse surface of the die bonding pad.

2. A semiconductor light emitting device comprising:

a lead frame having a constant thickness;

a semiconductor light emitting element supported by the lead frame;

a resin case covering part of the lead frame; and

a light transmitting member covering the semiconductor light emitting element;

wherein the lead frame includes a first frame element and a second frame element, the first frame element including a die bonding pad and first terminal, the second frame element including an elevated portion and a second terminal,

wherein the first terminal and the second terminal project from a same side surface of the resin case,

wherein the die bonding pad includes an obverse surface on which the semiconductor light emitting element is mounted and a reverse surface exposed from the resin case,

wherein the first frame element includes an additional elevated portion that is offset with respect to the obverse surface of the die bonding pad in a direction normal to the obverse surface,

wherein the lead frame includes an easily deformable portion embedded in the resin case, the easily deformable portion connecting the die bonding pad and the additional elevated portion, and

wherein the easily deformable portion includes a rectangular frame-shaped portion, a first bridge portion and a second bridge portion, the first bridge portion connecting the frame-shaped portion and the die bonding pad to each other, the second bridge portion connecting the frame-shaped portion and the additional elevated portion to each other.

5. A semiconductor light emitting device comprising:

a lead frame having a constant thickness;

a semiconductor light emitting element supported by the lead frame;

a resin case covering part of the lead frame; and

a light transmitting member covering the semiconductor light emitting element;

wherein the lead frame includes a first frame element and a second frame element, the first frame element including a die bonding pad and first terminal, the second frame element including an elevated portion and a second terminal,

wherein the first terminal and the second terminal project from a same side surface of the resin case,

wherein the die bonding pad includes an obverse surface on which the semiconductor light emitting element is mounted and a reverse surface exposed from the resin case,

wherein the first frame element includes an additional elevated portion that is offset with respect to the obverse surface of the die bonding pad in a direction normal to the obverse surface, and

wherein the lead frame includes an easily deformable portion embedded in the resin case, the easily deformable portion connecting the die bonding pad and the additional elevated portion,

the semiconductor light emitting device further comprising a zener diode and a wire, wherein the zener diode is mounted on the additional elevated portion and connected to the elevated portion of the second frame element by the wire.

13. A semiconductor light emitting device comprising:

a lead frame having a constant thickness;

a semiconductor light emitting element supported by the lead frame;

a resin case covering part of the lead frame; and

a light transmitting member covering the semiconductor light emitting element;

wherein the lead frame includes a first frame element and a second frame element, the first frame element including a die bonding pad and first terminal, the second frame element including an elevated portion and a second terminal,

wherein the first terminal and the second terminal project from a same side surface of the resin case,

wherein the die bonding pad includes an obverse surface on which the semiconductor light emitting element is mounted and a reverse surface exposed from the resin case,

wherein the first frame element includes an additional elevated portion that is offset with respect to the obverse surface of the die bonding pad in a direction normal to the obverse surface,

wherein the lead frame includes an easily deformable portion embedded in the resin case, the easily deformable portion connecting the die bonding pad and the additional elevated portion, and

wherein the first frame element includes a third terminal and a fourth terminal both directly connected to the die bonding pad, and the die bonding pad, the third terminal and the fourth terminal are, as a whole, flat.

14. The semiconductor light emitting device according to claim 13, wherein each of the third terminal and the fourth terminal includes a reverse surface exposed from the resin case.